_ Git - rust-lightning/blob - lightning/src/ln/channel.rs

   1 // This file is Copyright its original authors, visible in version control
   2 // history.
   3 //
   4 // This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
   5 // or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   6 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
   7 // You may not use this file except in accordance with one or both of these
   8 // licenses.
   9
  10 use bitcoin::blockdata::script::{Script,Builder};
  11 use bitcoin::blockdata::transaction::{TxIn, TxOut, Transaction, SigHashType};
  12 use bitcoin::util::bip143;
  13 use bitcoin::consensus::encode;
  14
  15 use bitcoin::hashes::Hash;
  16 use bitcoin::hashes::sha256::Hash as Sha256;
  17 use bitcoin::hashes::sha256d::Hash as Sha256d;
  18 use bitcoin::hash_types::{Txid, BlockHash};
  19
  20 use bitcoin::secp256k1::constants::PUBLIC_KEY_SIZE;
  21 use bitcoin::secp256k1::key::{PublicKey,SecretKey};
  22 use bitcoin::secp256k1::{Secp256k1,Signature};
  23 use bitcoin::secp256k1;
  24
  25 use ln::{PaymentPreimage, PaymentHash};
  26 use ln::features::{ChannelFeatures, InitFeatures};
  27 use ln::msgs;
  28 use ln::msgs::{DecodeError, OptionalField, DataLossProtect};
  29 use ln::script::ShutdownScript;
  30 use ln::channelmanager::{PendingHTLCStatus, HTLCSource, HTLCFailReason, HTLCFailureMsg, PendingHTLCInfo, RAACommitmentOrder, BREAKDOWN_TIMEOUT, MIN_CLTV_EXPIRY_DELTA, MAX_LOCAL_BREAKDOWN_TIMEOUT};
  31 use ln::chan_utils::{CounterpartyCommitmentSecrets, TxCreationKeys, HTLCOutputInCommitment, HTLC_SUCCESS_TX_WEIGHT, HTLC_TIMEOUT_TX_WEIGHT, make_funding_redeemscript, ChannelPublicKeys, CommitmentTransaction, HolderCommitmentTransaction, ChannelTransactionParameters, CounterpartyChannelTransactionParameters, MAX_HTLCS, get_commitment_transaction_number_obscure_factor};
  32 use ln::chan_utils;
  33 use chain::BestBlock;
  34 use chain::chaininterface::{FeeEstimator,ConfirmationTarget};
  35 use chain::channelmonitor::{ChannelMonitor, ChannelMonitorUpdate, ChannelMonitorUpdateStep, HTLC_FAIL_BACK_BUFFER};
  36 use chain::transaction::{OutPoint, TransactionData};
  37 use chain::keysinterface::{Sign, KeysInterface};
  38 use util::transaction_utils;
  39 use util::ser::{Readable, ReadableArgs, Writeable, Writer, VecWriter};
  40 use util::logger::Logger;
  41 use util::errors::APIError;
  42 use util::config::{UserConfig,ChannelConfig};
  43 use util::scid_utils::scid_from_parts;
  44
  45 use io;
  46 use prelude::*;
  47 use core::{cmp,mem,fmt};
  48 use core::convert::TryFrom;
  49 use core::ops::Deref;
  50 #[cfg(any(test, feature = "fuzztarget", debug_assertions))]
  51 use sync::Mutex;
  52 use bitcoin::hashes::hex::ToHex;
  53
  54 #[cfg(test)]
  55 pub struct ChannelValueStat {
  56         pub value_to_self_msat: u64,
  57         pub channel_value_msat: u64,
  58         pub channel_reserve_msat: u64,
  59         pub pending_outbound_htlcs_amount_msat: u64,
  60         pub pending_inbound_htlcs_amount_msat: u64,
  61         pub holding_cell_outbound_amount_msat: u64,
  62         pub counterparty_max_htlc_value_in_flight_msat: u64, // outgoing
  63         pub counterparty_dust_limit_msat: u64,
  64 }
  65
  66 #[derive(Clone, Copy, PartialEq)]
  67 enum FeeUpdateState {
  68         // Inbound states mirroring InboundHTLCState
  69         RemoteAnnounced,
  70         AwaitingRemoteRevokeToAnnounce,
  71         // Note that we do not have a AwaitingAnnouncedRemoteRevoke variant here as it is universally
  72         // handled the same as `Committed`, with the only exception in `InboundHTLCState` being the
  73         // distinction of when we allow ourselves to forward the HTLC. Because we aren't "forwarding"
  74         // the fee update anywhere, we can simply consider the fee update `Committed` immediately
  75         // instead of setting it to AwaitingAnnouncedRemoteRevoke.
  76
  77         // Outbound state can only be `LocalAnnounced` or `Committed`
  78         Outbound,
  79 }
  80
  81 enum InboundHTLCRemovalReason {
  82         FailRelay(msgs::OnionErrorPacket),
  83         FailMalformed(([u8; 32], u16)),
  84         Fulfill(PaymentPreimage),
  85 }
  86
  87 enum InboundHTLCState {
  88         /// Offered by remote, to be included in next local commitment tx. I.e., the remote sent an
  89         /// update_add_htlc message for this HTLC.
  90         RemoteAnnounced(PendingHTLCStatus),
  91         /// Included in a received commitment_signed message (implying we've
  92         /// revoke_and_ack'd it), but the remote hasn't yet revoked their previous
  93         /// state (see the example below). We have not yet included this HTLC in a
  94         /// commitment_signed message because we are waiting on the remote's
  95         /// aforementioned state revocation. One reason this missing remote RAA
  96         /// (revoke_and_ack) blocks us from constructing a commitment_signed message
  97         /// is because every time we create a new "state", i.e. every time we sign a
  98         /// new commitment tx (see [BOLT #2]), we need a new per_commitment_point,
  99         /// which are provided one-at-a-time in each RAA. E.g., the last RAA they
 100         /// sent provided the per_commitment_point for our current commitment tx.
 101         /// The other reason we should not send a commitment_signed without their RAA
 102         /// is because their RAA serves to ACK our previous commitment_signed.
 103         ///
 104         /// Here's an example of how an HTLC could come to be in this state:
 105         /// remote --> update_add_htlc(prev_htlc)   --> local
 106         /// remote --> commitment_signed(prev_htlc) --> local
 107         /// remote <-- revoke_and_ack               <-- local
 108         /// remote <-- commitment_signed(prev_htlc) <-- local
 109         /// [note that here, the remote does not respond with a RAA]
 110         /// remote --> update_add_htlc(this_htlc)   --> local
 111         /// remote --> commitment_signed(prev_htlc, this_htlc) --> local
 112         /// Now `this_htlc` will be assigned this state. It's unable to be officially
 113         /// accepted, i.e. included in a commitment_signed, because we're missing the
 114         /// RAA that provides our next per_commitment_point. The per_commitment_point
 115         /// is used to derive commitment keys, which are used to construct the
 116         /// signatures in a commitment_signed message.
 117         /// Implies AwaitingRemoteRevoke.
 118         ///
 119         /// [BOLT #2]: https://github.com/lightningnetwork/lightning-rfc/blob/master/02-peer-protocol.md
 120         AwaitingRemoteRevokeToAnnounce(PendingHTLCStatus),
 121         /// Included in a received commitment_signed message (implying we've revoke_and_ack'd it).
 122         /// We have also included this HTLC in our latest commitment_signed and are now just waiting
 123         /// on the remote's revoke_and_ack to make this HTLC an irrevocable part of the state of the
 124         /// channel (before it can then get forwarded and/or removed).
 125         /// Implies AwaitingRemoteRevoke.
 126         AwaitingAnnouncedRemoteRevoke(PendingHTLCStatus),
 127         Committed,
 128         /// Removed by us and a new commitment_signed was sent (if we were AwaitingRemoteRevoke when we
 129         /// created it we would have put it in the holding cell instead). When they next revoke_and_ack
 130         /// we'll drop it.
 131         /// Note that we have to keep an eye on the HTLC until we've received a broadcastable
 132         /// commitment transaction without it as otherwise we'll have to force-close the channel to
 133         /// claim it before the timeout (obviously doesn't apply to revoked HTLCs that we can't claim
 134         /// anyway). That said, ChannelMonitor does this for us (see
 135         /// ChannelMonitor::should_broadcast_holder_commitment_txn) so we actually remove the HTLC from
 136         /// our own local state before then, once we're sure that the next commitment_signed and
 137         /// ChannelMonitor::provide_latest_local_commitment_tx will not include this HTLC.
 138         LocalRemoved(InboundHTLCRemovalReason),
 139 }
 140
 141 struct InboundHTLCOutput {
 142         htlc_id: u64,
 143         amount_msat: u64,
 144         cltv_expiry: u32,
 145         payment_hash: PaymentHash,
 146         state: InboundHTLCState,
 147 }
 148
 149 enum OutboundHTLCState {
 150         /// Added by us and included in a commitment_signed (if we were AwaitingRemoteRevoke when we
 151         /// created it we would have put it in the holding cell instead). When they next revoke_and_ack
 152         /// we will promote to Committed (note that they may not accept it until the next time we
 153         /// revoke, but we don't really care about that:
 154         ///  * they've revoked, so worst case we can announce an old state and get our (option on)
 155         ///    money back (though we won't), and,
 156         ///  * we'll send them a revoke when they send a commitment_signed, and since only they're
 157         ///    allowed to remove it, the "can only be removed once committed on both sides" requirement
 158         ///    doesn't matter to us and it's up to them to enforce it, worst-case they jump ahead but
 159         ///    we'll never get out of sync).
 160         /// Note that we Box the OnionPacket as it's rather large and we don't want to blow up
 161         /// OutboundHTLCOutput's size just for a temporary bit
 162         LocalAnnounced(Box<msgs::OnionPacket>),
 163         Committed,
 164         /// Remote removed this (outbound) HTLC. We're waiting on their commitment_signed to finalize
 165         /// the change (though they'll need to revoke before we fail the payment).
 166         RemoteRemoved(Option<HTLCFailReason>),
 167         /// Remote removed this and sent a commitment_signed (implying we've revoke_and_ack'ed it), but
 168         /// the remote side hasn't yet revoked their previous state, which we need them to do before we
 169         /// can do any backwards failing. Implies AwaitingRemoteRevoke.
 170         /// We also have not yet removed this HTLC in a commitment_signed message, and are waiting on a
 171         /// remote revoke_and_ack on a previous state before we can do so.
 172         AwaitingRemoteRevokeToRemove(Option<HTLCFailReason>),
 173         /// Remote removed this and sent a commitment_signed (implying we've revoke_and_ack'ed it), but
 174         /// the remote side hasn't yet revoked their previous state, which we need them to do before we
 175         /// can do any backwards failing. Implies AwaitingRemoteRevoke.
 176         /// We have removed this HTLC in our latest commitment_signed and are now just waiting on a
 177         /// revoke_and_ack to drop completely.
 178         AwaitingRemovedRemoteRevoke(Option<HTLCFailReason>),
 179 }
 180
 181 struct OutboundHTLCOutput {
 182         htlc_id: u64,
 183         amount_msat: u64,
 184         cltv_expiry: u32,
 185         payment_hash: PaymentHash,
 186         state: OutboundHTLCState,
 187         source: HTLCSource,
 188 }
 189
 190 /// See AwaitingRemoteRevoke ChannelState for more info
 191 enum HTLCUpdateAwaitingACK {
 192         AddHTLC { // TODO: Time out if we're getting close to cltv_expiry
 193                 // always outbound
 194                 amount_msat: u64,
 195                 cltv_expiry: u32,
 196                 payment_hash: PaymentHash,
 197                 source: HTLCSource,
 198                 onion_routing_packet: msgs::OnionPacket,
 199         },
 200         ClaimHTLC {
 201                 payment_preimage: PaymentPreimage,
 202                 htlc_id: u64,
 203         },
 204         FailHTLC {
 205                 htlc_id: u64,
 206                 err_packet: msgs::OnionErrorPacket,
 207         },
 208 }
 209
 210 /// There are a few "states" and then a number of flags which can be applied:
 211 /// We first move through init with OurInitSent -> TheirInitSent -> FundingCreated -> FundingSent.
 212 /// TheirFundingLocked and OurFundingLocked then get set on FundingSent, and when both are set we
 213 /// move on to ChannelFunded.
 214 /// Note that PeerDisconnected can be set on both ChannelFunded and FundingSent.
 215 /// ChannelFunded can then get all remaining flags set on it, until we finish shutdown, then we
 216 /// move on to ShutdownComplete, at which point most calls into this channel are disallowed.
 217 enum ChannelState {
 218         /// Implies we have (or are prepared to) send our open_channel/accept_channel message
 219         OurInitSent = 1 << 0,
 220         /// Implies we have received their open_channel/accept_channel message
 221         TheirInitSent = 1 << 1,
 222         /// We have sent funding_created and are awaiting a funding_signed to advance to FundingSent.
 223         /// Note that this is nonsense for an inbound channel as we immediately generate funding_signed
 224         /// upon receipt of funding_created, so simply skip this state.
 225         FundingCreated = 4,
 226         /// Set when we have received/sent funding_created and funding_signed and are thus now waiting
 227         /// on the funding transaction to confirm. The FundingLocked flags are set to indicate when we
 228         /// and our counterparty consider the funding transaction confirmed.
 229         FundingSent = 8,
 230         /// Flag which can be set on FundingSent to indicate they sent us a funding_locked message.
 231         /// Once both TheirFundingLocked and OurFundingLocked are set, state moves on to ChannelFunded.
 232         TheirFundingLocked = 1 << 4,
 233         /// Flag which can be set on FundingSent to indicate we sent them a funding_locked message.
 234         /// Once both TheirFundingLocked and OurFundingLocked are set, state moves on to ChannelFunded.
 235         OurFundingLocked = 1 << 5,
 236         ChannelFunded = 64,
 237         /// Flag which is set on ChannelFunded and FundingSent indicating remote side is considered
 238         /// "disconnected" and no updates are allowed until after we've done a channel_reestablish
 239         /// dance.
 240         PeerDisconnected = 1 << 7,
 241         /// Flag which is set on ChannelFunded, FundingCreated, and FundingSent indicating the user has
 242         /// told us they failed to update our ChannelMonitor somewhere and we should pause sending any
 243         /// outbound messages until they've managed to do so.
 244         MonitorUpdateFailed = 1 << 8,
 245         /// Flag which implies that we have sent a commitment_signed but are awaiting the responding
 246         /// revoke_and_ack message. During this time period, we can't generate new commitment_signed
 247         /// messages as then we will be unable to determine which HTLCs they included in their
 248         /// revoke_and_ack implicit ACK, so instead we have to hold them away temporarily to be sent
 249         /// later.
 250         /// Flag is set on ChannelFunded.
 251         AwaitingRemoteRevoke = 1 << 9,
 252         /// Flag which is set on ChannelFunded or FundingSent after receiving a shutdown message from
 253         /// the remote end. If set, they may not add any new HTLCs to the channel, and we are expected
 254         /// to respond with our own shutdown message when possible.
 255         RemoteShutdownSent = 1 << 10,
 256         /// Flag which is set on ChannelFunded or FundingSent after sending a shutdown message. At this
 257         /// point, we may not add any new HTLCs to the channel.
 258         /// TODO: Investigate some kind of timeout mechanism by which point the remote end must provide
 259         /// us their shutdown.
 260         LocalShutdownSent = 1 << 11,
 261         /// We've successfully negotiated a closing_signed dance. At this point ChannelManager is about
 262         /// to drop us, but we store this anyway.
 263         ShutdownComplete = 4096,
 264 }
 265 const BOTH_SIDES_SHUTDOWN_MASK: u32 = ChannelState::LocalShutdownSent as u32 | ChannelState::RemoteShutdownSent as u32;
 266 const MULTI_STATE_FLAGS: u32 = BOTH_SIDES_SHUTDOWN_MASK | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32;
 267
 268 pub const INITIAL_COMMITMENT_NUMBER: u64 = (1 << 48) - 1;
 269
 270 /// The "channel disabled" bit in channel_update must be set based on whether we are connected to
 271 /// our counterparty or not. However, we don't want to announce updates right away to avoid
 272 /// spamming the network with updates if the connection is flapping. Instead, we "stage" updates to
 273 /// our channel_update message and track the current state here.
 274 /// See implementation at [`super::channelmanager::ChannelManager::timer_tick_occurred`].
 275 #[derive(Clone, Copy, PartialEq)]
 276 pub(super) enum ChannelUpdateStatus {
 277         /// We've announced the channel as enabled and are connected to our peer.
 278         Enabled,
 279         /// Our channel is no longer live, but we haven't announced the channel as disabled yet.
 280         DisabledStaged,
 281         /// Our channel is live again, but we haven't announced the channel as enabled yet.
 282         EnabledStaged,
 283         /// We've announced the channel as disabled.
 284         Disabled,
 285 }
 286
 287 /// An enum indicating whether the local or remote side offered a given HTLC.
 288 enum HTLCInitiator {
 289         LocalOffered,
 290         RemoteOffered,
 291 }
 292
 293 /// An enum gathering stats on pending HTLCs, either inbound or outbound side.
 294 struct HTLCStats {
 295         pending_htlcs: u32,
 296         pending_htlcs_value_msat: u64,
 297         on_counterparty_tx_dust_exposure_msat: u64,
 298         on_holder_tx_dust_exposure_msat: u64,
 299 }
 300
 301 /// Used when calculating whether we or the remote can afford an additional HTLC.
 302 struct HTLCCandidate {
 303         amount_msat: u64,
 304         origin: HTLCInitiator,
 305 }
 306
 307 impl HTLCCandidate {
 308         fn new(amount_msat: u64, origin: HTLCInitiator) -> Self {
 309                 Self {
 310                         amount_msat,
 311                         origin,
 312                 }
 313         }
 314 }
 315
 316 /// Information needed for constructing an invoice route hint for this channel.
 317 #[derive(Clone, Debug, PartialEq)]
 318 pub struct CounterpartyForwardingInfo {
 319         /// Base routing fee in millisatoshis.
 320         pub fee_base_msat: u32,
 321         /// Amount in millionths of a satoshi the channel will charge per transferred satoshi.
 322         pub fee_proportional_millionths: u32,
 323         /// The minimum difference in cltv_expiry between an ingoing HTLC and its outgoing counterpart,
 324         /// such that the outgoing HTLC is forwardable to this counterparty. See `msgs::ChannelUpdate`'s
 325         /// `cltv_expiry_delta` for more details.
 326         pub cltv_expiry_delta: u16,
 327 }
 328
 329 /// A return value enum for get_update_fulfill_htlc. See UpdateFulfillCommitFetch variants for
 330 /// description
 331 enum UpdateFulfillFetch {
 332         NewClaim {
 333                 monitor_update: ChannelMonitorUpdate,
 334                 htlc_value_msat: u64,
 335                 msg: Option<msgs::UpdateFulfillHTLC>,
 336         },
 337         DuplicateClaim {},
 338 }
 339
 340 /// The return type of get_update_fulfill_htlc_and_commit.
 341 pub enum UpdateFulfillCommitFetch {
 342         /// Indicates the HTLC fulfill is new, and either generated an update_fulfill message, placed
 343         /// it in the holding cell, or re-generated the update_fulfill message after the same claim was
 344         /// previously placed in the holding cell (and has since been removed).
 345         NewClaim {
 346                 /// The ChannelMonitorUpdate which places the new payment preimage in the channel monitor
 347                 monitor_update: ChannelMonitorUpdate,
 348                 /// The value of the HTLC which was claimed, in msat.
 349                 htlc_value_msat: u64,
 350                 /// The update_fulfill message and commitment_signed message (if the claim was not placed
 351                 /// in the holding cell).
 352                 msgs: Option<(msgs::UpdateFulfillHTLC, msgs::CommitmentSigned)>,
 353         },
 354         /// Indicates the HTLC fulfill is duplicative and already existed either in the holding cell
 355         /// or has been forgotten (presumably previously claimed).
 356         DuplicateClaim {},
 357 }
 358
 359 /// If the majority of the channels funds are to the fundee and the initiator holds only just
 360 /// enough funds to cover their reserve value, channels are at risk of getting "stuck". Because the
 361 /// initiator controls the feerate, if they then go to increase the channel fee, they may have no
 362 /// balance but the fundee is unable to send a payment as the increase in fee more than drains
 363 /// their reserve value. Thus, neither side can send a new HTLC and the channel becomes useless.
 364 /// Thus, before sending an HTLC when we are the initiator, we check that the feerate can increase
 365 /// by this multiple without hitting this case, before sending.
 366 /// This multiple is effectively the maximum feerate "jump" we expect until more HTLCs flow over
 367 /// the channel. Sadly, there isn't really a good number for this - if we expect to have no new
 368 /// HTLCs for days we may need this to suffice for feerate increases across days, but that may
 369 /// leave the channel less usable as we hold a bigger reserve.
 370 #[cfg(fuzzing)]
 371 pub const FEE_SPIKE_BUFFER_FEE_INCREASE_MULTIPLE: u64 = 2;
 372 #[cfg(not(fuzzing))]
 373 const FEE_SPIKE_BUFFER_FEE_INCREASE_MULTIPLE: u64 = 2;
 374
 375 // TODO: We should refactor this to be an Inbound/OutboundChannel until initial setup handshaking
 376 // has been completed, and then turn into a Channel to get compiler-time enforcement of things like
 377 // calling channel_id() before we're set up or things like get_outbound_funding_signed on an
 378 // inbound channel.
 379 //
 380 // Holder designates channel data owned for the benefice of the user client.
 381 // Counterparty designates channel data owned by the another channel participant entity.
 382 pub(super) struct Channel<Signer: Sign> {
 383         #[cfg(any(test, feature = "_test_utils"))]
 384         pub(crate) config: ChannelConfig,
 385         #[cfg(not(any(test, feature = "_test_utils")))]
 386         config: ChannelConfig,
 387
 388         user_id: u64,
 389
 390         channel_id: [u8; 32],
 391         channel_state: u32,
 392         secp_ctx: Secp256k1<secp256k1::All>,
 393         channel_value_satoshis: u64,
 394
 395         latest_monitor_update_id: u64,
 396
 397         holder_signer: Signer,
 398         shutdown_scriptpubkey: Option<ShutdownScript>,
 399         destination_script: Script,
 400
 401         // Our commitment numbers start at 2^48-1 and count down, whereas the ones used in transaction
 402         // generation start at 0 and count up...this simplifies some parts of implementation at the
 403         // cost of others, but should really just be changed.
 404
 405         cur_holder_commitment_transaction_number: u64,
 406         cur_counterparty_commitment_transaction_number: u64,
 407         value_to_self_msat: u64, // Excluding all pending_htlcs, excluding fees
 408         pending_inbound_htlcs: Vec<InboundHTLCOutput>,
 409         pending_outbound_htlcs: Vec<OutboundHTLCOutput>,
 410         holding_cell_htlc_updates: Vec<HTLCUpdateAwaitingACK>,
 411
 412         /// When resending CS/RAA messages on channel monitor restoration or on reconnect, we always
 413         /// need to ensure we resend them in the order we originally generated them. Note that because
 414         /// there can only ever be one in-flight CS and/or one in-flight RAA at any time, it is
 415         /// sufficient to simply set this to the opposite of any message we are generating as we
 416         /// generate it. ie when we generate a CS, we set this to RAAFirst as, if there is a pending
 417         /// in-flight RAA to resend, it will have been the first thing we generated, and thus we should
 418         /// send it first.
 419         resend_order: RAACommitmentOrder,
 420
 421         monitor_pending_funding_locked: bool,
 422         monitor_pending_revoke_and_ack: bool,
 423         monitor_pending_commitment_signed: bool,
 424         monitor_pending_forwards: Vec<(PendingHTLCInfo, u64)>,
 425         monitor_pending_failures: Vec<(HTLCSource, PaymentHash, HTLCFailReason)>,
 426
 427         // pending_update_fee is filled when sending and receiving update_fee
 428         // For outbound channel, feerate_per_kw is updated with the value from
 429         // pending_update_fee when revoke_and_ack is received
 430         //
 431         // For inbound channel, feerate_per_kw is updated when it receives
 432         // commitment_signed and revoke_and_ack is generated
 433         // The pending value is kept when another pair of update_fee and commitment_signed
 434         // is received during AwaitingRemoteRevoke and relieved when the expected
 435         // revoke_and_ack is received and new commitment_signed is generated to be
 436         // sent to the funder. Otherwise, the pending value is removed when receiving
 437         // commitment_signed.
 438         pending_update_fee: Option<(u32, FeeUpdateState)>,
 439         // update_fee() during ChannelState::AwaitingRemoteRevoke is hold in
 440         // holdina_cell_update_fee then moved to pending_udpate_fee when revoke_and_ack
 441         // is received. holding_cell_update_fee is updated when there are additional
 442         // update_fee() during ChannelState::AwaitingRemoteRevoke.
 443         holding_cell_update_fee: Option<u32>,
 444         next_holder_htlc_id: u64,
 445         next_counterparty_htlc_id: u64,
 446         update_time_counter: u32,
 447         feerate_per_kw: u32,
 448
 449         #[cfg(debug_assertions)]
 450         /// Max to_local and to_remote outputs in a locally-generated commitment transaction
 451         holder_max_commitment_tx_output: Mutex<(u64, u64)>,
 452         #[cfg(debug_assertions)]
 453         /// Max to_local and to_remote outputs in a remote-generated commitment transaction
 454         counterparty_max_commitment_tx_output: Mutex<(u64, u64)>,
 455
 456         last_sent_closing_fee: Option<(u64, Signature)>, // (fee, holder_sig)
 457         closing_fee_limits: Option<(u64, u64)>,
 458         target_closing_feerate_sats_per_kw: Option<u32>,
 459
 460         /// If our counterparty sent us a closing_signed while we were waiting for a `ChannelMonitor`
 461         /// update, we need to delay processing it until later. We do that here by simply storing the
 462         /// closing_signed message and handling it in `maybe_propose_closing_signed`.
 463         pending_counterparty_closing_signed: Option<msgs::ClosingSigned>,
 464
 465         /// The hash of the block in which the funding transaction was included.
 466         funding_tx_confirmed_in: Option<BlockHash>,
 467         funding_tx_confirmation_height: u32,
 468         short_channel_id: Option<u64>,
 469
 470         counterparty_dust_limit_satoshis: u64,
 471         #[cfg(test)]
 472         pub(super) holder_dust_limit_satoshis: u64,
 473         #[cfg(not(test))]
 474         holder_dust_limit_satoshis: u64,
 475         #[cfg(test)]
 476         pub(super) counterparty_max_htlc_value_in_flight_msat: u64,
 477         #[cfg(not(test))]
 478         counterparty_max_htlc_value_in_flight_msat: u64,
 479         //get_holder_max_htlc_value_in_flight_msat(): u64,
 480         /// minimum channel reserve for self to maintain - set by them.
 481         counterparty_selected_channel_reserve_satoshis: Option<u64>,
 482         // get_holder_selected_channel_reserve_satoshis(channel_value_sats: u64): u64
 483         counterparty_htlc_minimum_msat: u64,
 484         holder_htlc_minimum_msat: u64,
 485         #[cfg(test)]
 486         pub counterparty_max_accepted_htlcs: u16,
 487         #[cfg(not(test))]
 488         counterparty_max_accepted_htlcs: u16,
 489         //implied by OUR_MAX_HTLCS: max_accepted_htlcs: u16,
 490         minimum_depth: Option<u32>,
 491
 492         counterparty_forwarding_info: Option<CounterpartyForwardingInfo>,
 493
 494         pub(crate) channel_transaction_parameters: ChannelTransactionParameters,
 495         funding_transaction: Option<Transaction>,
 496
 497         counterparty_cur_commitment_point: Option<PublicKey>,
 498         counterparty_prev_commitment_point: Option<PublicKey>,
 499         counterparty_node_id: PublicKey,
 500
 501         counterparty_shutdown_scriptpubkey: Option<Script>,
 502
 503         commitment_secrets: CounterpartyCommitmentSecrets,
 504
 505         channel_update_status: ChannelUpdateStatus,
 506
 507         /// Our counterparty's channel_announcement signatures provided in announcement_signatures.
 508         /// This can be used to rebroadcast the channel_announcement message later.
 509         announcement_sigs: Option<(Signature, Signature)>,
 510
 511         // We save these values so we can make sure `next_local_commit_tx_fee_msat` and
 512         // `next_remote_commit_tx_fee_msat` properly predict what the next commitment transaction fee will
 513         // be, by comparing the cached values to the fee of the tranaction generated by
 514         // `build_commitment_transaction`.
 515         #[cfg(any(test, feature = "fuzztarget"))]
 516         next_local_commitment_tx_fee_info_cached: Mutex<Option<CommitmentTxInfoCached>>,
 517         #[cfg(any(test, feature = "fuzztarget"))]
 518         next_remote_commitment_tx_fee_info_cached: Mutex<Option<CommitmentTxInfoCached>>,
 519
 520         /// lnd has a long-standing bug where, upon reconnection, if the channel is not yet confirmed
 521         /// they will not send a channel_reestablish until the channel locks in. Then, they will send a
 522         /// funding_locked *before* sending the channel_reestablish (which is clearly a violation of
 523         /// the BOLT specs). We copy c-lightning's workaround here and simply store the funding_locked
 524         /// message until we receive a channel_reestablish.
 525         ///
 526         /// See-also <https://github.com/lightningnetwork/lnd/issues/4006>
 527         pub workaround_lnd_bug_4006: Option<msgs::FundingLocked>,
 528
 529         #[cfg(any(test, feature = "fuzztarget"))]
 530         // When we receive an HTLC fulfill on an outbound path, we may immediately fulfill the
 531         // corresponding HTLC on the inbound path. If, then, the outbound path channel is
 532         // disconnected and reconnected (before we've exchange commitment_signed and revoke_and_ack
 533         // messages), they may re-broadcast their update_fulfill_htlc, causing a duplicate claim. This
 534         // is fine, but as a sanity check in our failure to generate the second claim, we check here
 535         // that the original was a claim, and that we aren't now trying to fulfill a failed HTLC.
 536         historical_inbound_htlc_fulfills: HashSet<u64>,
 537 }
 538
 539 #[cfg(any(test, feature = "fuzztarget"))]
 540 struct CommitmentTxInfoCached {
 541         fee: u64,
 542         total_pending_htlcs: usize,
 543         next_holder_htlc_id: u64,
 544         next_counterparty_htlc_id: u64,
 545         feerate: u32,
 546 }
 547
 548 pub const OUR_MAX_HTLCS: u16 = 50; //TODO
 549
 550 #[cfg(not(test))]
 551 const COMMITMENT_TX_BASE_WEIGHT: u64 = 724;
 552 #[cfg(test)]
 553 pub const COMMITMENT_TX_BASE_WEIGHT: u64 = 724;
 554 #[cfg(not(test))]
 555 const COMMITMENT_TX_WEIGHT_PER_HTLC: u64 = 172;
 556 #[cfg(test)]
 557 pub const COMMITMENT_TX_WEIGHT_PER_HTLC: u64 = 172;
 558
 559 /// Maximmum `funding_satoshis` value, according to the BOLT #2 specification
 560 /// it's 2^24.
 561 pub const MAX_FUNDING_SATOSHIS: u64 = 1 << 24;
 562
 563 /// Maximum counterparty `dust_limit_satoshis` allowed. 2 * standard dust threshold on p2wsh output
 564 /// Scales up on Bitcoin Core's proceeding policy with dust outputs. A typical p2wsh output is 43
 565 /// bytes to which Core's `GetDustThreshold()` sums up a minimal spend of 67 bytes (even if
 566 /// a p2wsh witnessScript might be *effectively* smaller), `dustRelayFee` is set to 3000sat/kb, thus
 567 /// 110 * 3000 / 1000 = 330. Per-protocol rules, all time-sensitive outputs are p2wsh, a value of
 568 /// 330 sats is the lower bound desired to ensure good propagation of transactions. We give a bit
 569 /// of margin to our counterparty and pick up 660 satoshis as an accepted `dust_limit_satoshis`
 570 /// upper bound to avoid negotiation conflicts with other implementations.
 571 pub const MAX_DUST_LIMIT_SATOSHIS: u64 = 2 * 330;
 572
 573 /// A typical p2wsh output is 43 bytes to which Core's `GetDustThreshold()` sums up a minimal
 574 /// spend of 67 bytes (even if a p2wsh witnessScript might be *effectively* smaller), `dustRelayFee`
 575 /// is set to 3000sat/kb, thus 110 * 3000 / 1000 = 330. Per-protocol rules, all time-sensitive outputs
 576 /// are p2wsh, a value of 330 sats is the lower bound desired to ensure good propagation of transactions.
 577 pub const MIN_DUST_LIMIT_SATOSHIS: u64 = 330;
 578
 579 /// Used to return a simple Error back to ChannelManager. Will get converted to a
 580 /// msgs::ErrorAction::SendErrorMessage or msgs::ErrorAction::IgnoreError as appropriate with our
 581 /// channel_id in ChannelManager.
 582 pub(super) enum ChannelError {
 583         Ignore(String),
 584         Warn(String),
 585         Close(String),
 586         CloseDelayBroadcast(String),
 587 }
 588
 589 impl fmt::Debug for ChannelError {
 590         fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
 591                 match self {
 592                         &ChannelError::Ignore(ref e) => write!(f, "Ignore : {}", e),
 593                         &ChannelError::Warn(ref e) => write!(f, "Warn : {}", e),
 594                         &ChannelError::Close(ref e) => write!(f, "Close : {}", e),
 595                         &ChannelError::CloseDelayBroadcast(ref e) => write!(f, "CloseDelayBroadcast : {}", e)
 596                 }
 597         }
 598 }
 599
 600 macro_rules! secp_check {
 601         ($res: expr, $err: expr) => {
 602                 match $res {
 603                         Ok(thing) => thing,
 604                         Err(_) => return Err(ChannelError::Close($err)),
 605                 }
 606         };
 607 }
 608
 609 impl<Signer: Sign> Channel<Signer> {
 610         // Convert constants + channel value to limits:
 611         fn get_holder_max_htlc_value_in_flight_msat(channel_value_satoshis: u64) -> u64 {
 612                 channel_value_satoshis * 1000 / 10 //TODO
 613         }
 614
 615         /// Returns a minimum channel reserve value the remote needs to maintain,
 616         /// required by us.
 617         ///
 618         /// Guaranteed to return a value no larger than channel_value_satoshis
 619         pub(crate) fn get_holder_selected_channel_reserve_satoshis(channel_value_satoshis: u64) -> u64 {
 620                 let (q, _) = channel_value_satoshis.overflowing_div(100);
 621                 cmp::min(channel_value_satoshis, cmp::max(q, 1000)) //TODO
 622         }
 623
 624         // Constructors:
 625         pub fn new_outbound<K: Deref, F: Deref>(fee_estimator: &F, keys_provider: &K, counterparty_node_id: PublicKey, their_features: &InitFeatures, channel_value_satoshis: u64, push_msat: u64, user_id: u64, config: &UserConfig) -> Result<Channel<Signer>, APIError>
 626         where K::Target: KeysInterface<Signer = Signer>,
 627               F::Target: FeeEstimator,
 628         {
 629                 let holder_selected_contest_delay = config.own_channel_config.our_to_self_delay;
 630                 let holder_signer = keys_provider.get_channel_signer(false, channel_value_satoshis);
 631                 let pubkeys = holder_signer.pubkeys().clone();
 632
 633                 if channel_value_satoshis >= MAX_FUNDING_SATOSHIS {
 634                         return Err(APIError::APIMisuseError{err: format!("funding_value must be smaller than {}, it was {}", MAX_FUNDING_SATOSHIS, channel_value_satoshis)});
 635                 }
 636                 let channel_value_msat = channel_value_satoshis * 1000;
 637                 if push_msat > channel_value_msat {
 638                         return Err(APIError::APIMisuseError { err: format!("Push value ({}) was larger than channel_value ({})", push_msat, channel_value_msat) });
 639                 }
 640                 if holder_selected_contest_delay < BREAKDOWN_TIMEOUT {
 641                         return Err(APIError::APIMisuseError {err: format!("Configured with an unreasonable our_to_self_delay ({}) putting user funds at risks", holder_selected_contest_delay)});
 642                 }
 643                 let holder_selected_channel_reserve_satoshis = Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(channel_value_satoshis);
 644                 if holder_selected_channel_reserve_satoshis < MIN_DUST_LIMIT_SATOSHIS {
 645                         return Err(APIError::APIMisuseError { err: format!("Holder selected channel  reserve below implemention limit dust_limit_satoshis {}", holder_selected_channel_reserve_satoshis) });
 646                 }
 647
 648                 let feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Normal);
 649
 650                 let mut secp_ctx = Secp256k1::new();
 651                 secp_ctx.seeded_randomize(&keys_provider.get_secure_random_bytes());
 652
 653                 let shutdown_scriptpubkey = if config.channel_options.commit_upfront_shutdown_pubkey {
 654                         Some(keys_provider.get_shutdown_scriptpubkey())
 655                 } else { None };
 656
 657                 if let Some(shutdown_scriptpubkey) = &shutdown_scriptpubkey {
 658                         if !shutdown_scriptpubkey.is_compatible(&their_features) {
 659                                 return Err(APIError::IncompatibleShutdownScript { script: shutdown_scriptpubkey.clone() });
 660                         }
 661                 }
 662
 663                 Ok(Channel {
 664                         user_id,
 665                         config: config.channel_options.clone(),
 666
 667                         channel_id: keys_provider.get_secure_random_bytes(),
 668                         channel_state: ChannelState::OurInitSent as u32,
 669                         secp_ctx,
 670                         channel_value_satoshis,
 671
 672                         latest_monitor_update_id: 0,
 673
 674                         holder_signer,
 675                         shutdown_scriptpubkey,
 676                         destination_script: keys_provider.get_destination_script(),
 677
 678                         cur_holder_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
 679                         cur_counterparty_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
 680                         value_to_self_msat: channel_value_satoshis * 1000 - push_msat,
 681
 682                         pending_inbound_htlcs: Vec::new(),
 683                         pending_outbound_htlcs: Vec::new(),
 684                         holding_cell_htlc_updates: Vec::new(),
 685                         pending_update_fee: None,
 686                         holding_cell_update_fee: None,
 687                         next_holder_htlc_id: 0,
 688                         next_counterparty_htlc_id: 0,
 689                         update_time_counter: 1,
 690
 691                         resend_order: RAACommitmentOrder::CommitmentFirst,
 692
 693                         monitor_pending_funding_locked: false,
 694                         monitor_pending_revoke_and_ack: false,
 695                         monitor_pending_commitment_signed: false,
 696                         monitor_pending_forwards: Vec::new(),
 697                         monitor_pending_failures: Vec::new(),
 698
 699                         #[cfg(debug_assertions)]
 700                         holder_max_commitment_tx_output: Mutex::new((channel_value_satoshis * 1000 - push_msat, push_msat)),
 701                         #[cfg(debug_assertions)]
 702                         counterparty_max_commitment_tx_output: Mutex::new((channel_value_satoshis * 1000 - push_msat, push_msat)),
 703
 704                         last_sent_closing_fee: None,
 705                         pending_counterparty_closing_signed: None,
 706                         closing_fee_limits: None,
 707                         target_closing_feerate_sats_per_kw: None,
 708
 709                         funding_tx_confirmed_in: None,
 710                         funding_tx_confirmation_height: 0,
 711                         short_channel_id: None,
 712
 713                         feerate_per_kw: feerate,
 714                         counterparty_dust_limit_satoshis: 0,
 715                         holder_dust_limit_satoshis: MIN_DUST_LIMIT_SATOSHIS,
 716                         counterparty_max_htlc_value_in_flight_msat: 0,
 717                         counterparty_selected_channel_reserve_satoshis: None, // Filled in in accept_channel
 718                         counterparty_htlc_minimum_msat: 0,
 719                         holder_htlc_minimum_msat: if config.own_channel_config.our_htlc_minimum_msat == 0 { 1 } else { config.own_channel_config.our_htlc_minimum_msat },
 720                         counterparty_max_accepted_htlcs: 0,
 721                         minimum_depth: None, // Filled in in accept_channel
 722
 723                         counterparty_forwarding_info: None,
 724
 725                         channel_transaction_parameters: ChannelTransactionParameters {
 726                                 holder_pubkeys: pubkeys,
 727                                 holder_selected_contest_delay: config.own_channel_config.our_to_self_delay,
 728                                 is_outbound_from_holder: true,
 729                                 counterparty_parameters: None,
 730                                 funding_outpoint: None
 731                         },
 732                         funding_transaction: None,
 733
 734                         counterparty_cur_commitment_point: None,
 735                         counterparty_prev_commitment_point: None,
 736                         counterparty_node_id,
 737
 738                         counterparty_shutdown_scriptpubkey: None,
 739
 740                         commitment_secrets: CounterpartyCommitmentSecrets::new(),
 741
 742                         channel_update_status: ChannelUpdateStatus::Enabled,
 743
 744                         announcement_sigs: None,
 745
 746                         #[cfg(any(test, feature = "fuzztarget"))]
 747                         next_local_commitment_tx_fee_info_cached: Mutex::new(None),
 748                         #[cfg(any(test, feature = "fuzztarget"))]
 749                         next_remote_commitment_tx_fee_info_cached: Mutex::new(None),
 750
 751                         workaround_lnd_bug_4006: None,
 752
 753                         #[cfg(any(test, feature = "fuzztarget"))]
 754                         historical_inbound_htlc_fulfills: HashSet::new(),
 755                 })
 756         }
 757
 758         fn check_remote_fee<F: Deref>(fee_estimator: &F, feerate_per_kw: u32) -> Result<(), ChannelError>
 759                 where F::Target: FeeEstimator
 760         {
 761                 let lower_limit = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background);
 762                 if feerate_per_kw < lower_limit {
 763                         return Err(ChannelError::Close(format!("Peer's feerate much too low. Actual: {}. Our expected lower limit: {}", feerate_per_kw, lower_limit)));
 764                 }
 765                 // We only bound the fee updates on the upper side to prevent completely absurd feerates,
 766                 // always accepting up to 25 sat/vByte or 10x our fee estimator's "High Priority" fee.
 767                 // We generally don't care too much if they set the feerate to something very high, but it
 768                 // could result in the channel being useless due to everything being dust.
 769                 let upper_limit = cmp::max(250 * 25,
 770                         fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::HighPriority) as u64 * 10);
 771                 if feerate_per_kw as u64 > upper_limit {
 772                         return Err(ChannelError::Close(format!("Peer's feerate much too high. Actual: {}. Our expected upper limit: {}", feerate_per_kw, upper_limit)));
 773                 }
 774                 Ok(())
 775         }
 776
 777         /// Creates a new channel from a remote sides' request for one.
 778         /// Assumes chain_hash has already been checked and corresponds with what we expect!
 779         pub fn new_from_req<K: Deref, F: Deref>(fee_estimator: &F, keys_provider: &K, counterparty_node_id: PublicKey, their_features: &InitFeatures, msg: &msgs::OpenChannel, user_id: u64, config: &UserConfig) -> Result<Channel<Signer>, ChannelError>
 780                 where K::Target: KeysInterface<Signer = Signer>,
 781           F::Target: FeeEstimator
 782         {
 783                 let holder_signer = keys_provider.get_channel_signer(true, msg.funding_satoshis);
 784                 let pubkeys = holder_signer.pubkeys().clone();
 785                 let counterparty_pubkeys = ChannelPublicKeys {
 786                         funding_pubkey: msg.funding_pubkey,
 787                         revocation_basepoint: msg.revocation_basepoint,
 788                         payment_point: msg.payment_point,
 789                         delayed_payment_basepoint: msg.delayed_payment_basepoint,
 790                         htlc_basepoint: msg.htlc_basepoint
 791                 };
 792                 let mut local_config = (*config).channel_options.clone();
 793
 794                 if config.own_channel_config.our_to_self_delay < BREAKDOWN_TIMEOUT {
 795                         return Err(ChannelError::Close(format!("Configured with an unreasonable our_to_self_delay ({}) putting user funds at risks. It must be greater than {}", config.own_channel_config.our_to_self_delay, BREAKDOWN_TIMEOUT)));
 796                 }
 797
 798                 // Check sanity of message fields:
 799                 if msg.funding_satoshis >= MAX_FUNDING_SATOSHIS {
 800                         return Err(ChannelError::Close(format!("Funding must be smaller than {}. It was {}", MAX_FUNDING_SATOSHIS, msg.funding_satoshis)));
 801                 }
 802                 if msg.channel_reserve_satoshis > msg.funding_satoshis {
 803                         return Err(ChannelError::Close(format!("Bogus channel_reserve_satoshis ({}). Must be not greater than funding_satoshis: {}", msg.channel_reserve_satoshis, msg.funding_satoshis)));
 804                 }
 805                 let funding_value = (msg.funding_satoshis - msg.channel_reserve_satoshis) * 1000;
 806                 if msg.push_msat > funding_value {
 807                         return Err(ChannelError::Close(format!("push_msat {} was larger than funding value {}", msg.push_msat, funding_value)));
 808                 }
 809                 if msg.dust_limit_satoshis > msg.funding_satoshis {
 810                         return Err(ChannelError::Close(format!("dust_limit_satoshis {} was larger than funding_satoshis {}. Peer never wants payout outputs?", msg.dust_limit_satoshis, msg.funding_satoshis)));
 811                 }
 812                 if msg.dust_limit_satoshis > msg.channel_reserve_satoshis {
 813                         return Err(ChannelError::Close(format!("Bogus; channel reserve ({}) is less than dust limit ({})", msg.channel_reserve_satoshis, msg.dust_limit_satoshis)));
 814                 }
 815                 let full_channel_value_msat = (msg.funding_satoshis - msg.channel_reserve_satoshis) * 1000;
 816                 if msg.htlc_minimum_msat >= full_channel_value_msat {
 817                         return Err(ChannelError::Close(format!("Minimum htlc value ({}) was larger than full channel value ({})", msg.htlc_minimum_msat, full_channel_value_msat)));
 818                 }
 819                 Channel::<Signer>::check_remote_fee(fee_estimator, msg.feerate_per_kw)?;
 820
 821                 let max_counterparty_selected_contest_delay = u16::min(config.peer_channel_config_limits.their_to_self_delay, MAX_LOCAL_BREAKDOWN_TIMEOUT);
 822                 if msg.to_self_delay > max_counterparty_selected_contest_delay {
 823                         return Err(ChannelError::Close(format!("They wanted our payments to be delayed by a needlessly long period. Upper limit: {}. Actual: {}", max_counterparty_selected_contest_delay, msg.to_self_delay)));
 824                 }
 825                 if msg.max_accepted_htlcs < 1 {
 826                         return Err(ChannelError::Close("0 max_accepted_htlcs makes for a useless channel".to_owned()));
 827                 }
 828                 if msg.max_accepted_htlcs > MAX_HTLCS {
 829                         return Err(ChannelError::Close(format!("max_accepted_htlcs was {}. It must not be larger than {}", msg.max_accepted_htlcs, MAX_HTLCS)));
 830                 }
 831
 832                 // Now check against optional parameters as set by config...
 833                 if msg.funding_satoshis < config.peer_channel_config_limits.min_funding_satoshis {
 834                         return Err(ChannelError::Close(format!("Funding satoshis ({}) is less than the user specified limit ({})", msg.funding_satoshis, config.peer_channel_config_limits.min_funding_satoshis)));
 835                 }
 836                 if msg.htlc_minimum_msat > config.peer_channel_config_limits.max_htlc_minimum_msat {
 837                         return Err(ChannelError::Close(format!("htlc_minimum_msat ({}) is higher than the user specified limit ({})", msg.htlc_minimum_msat,  config.peer_channel_config_limits.max_htlc_minimum_msat)));
 838                 }
 839                 if msg.max_htlc_value_in_flight_msat < config.peer_channel_config_limits.min_max_htlc_value_in_flight_msat {
 840                         return Err(ChannelError::Close(format!("max_htlc_value_in_flight_msat ({}) is less than the user specified limit ({})", msg.max_htlc_value_in_flight_msat, config.peer_channel_config_limits.min_max_htlc_value_in_flight_msat)));
 841                 }
 842                 if msg.channel_reserve_satoshis > config.peer_channel_config_limits.max_channel_reserve_satoshis {
 843                         return Err(ChannelError::Close(format!("channel_reserve_satoshis ({}) is higher than the user specified limit ({})", msg.channel_reserve_satoshis, config.peer_channel_config_limits.max_channel_reserve_satoshis)));
 844                 }
 845                 if msg.max_accepted_htlcs < config.peer_channel_config_limits.min_max_accepted_htlcs {
 846                         return Err(ChannelError::Close(format!("max_accepted_htlcs ({}) is less than the user specified limit ({})", msg.max_accepted_htlcs, config.peer_channel_config_limits.min_max_accepted_htlcs)));
 847                 }
 848                 if msg.dust_limit_satoshis < MIN_DUST_LIMIT_SATOSHIS {
 849                         return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is less than the implementation limit ({})", msg.dust_limit_satoshis, MIN_DUST_LIMIT_SATOSHIS)));
 850                 }
 851                 if msg.dust_limit_satoshis >  MAX_DUST_LIMIT_SATOSHIS {
 852                         return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is greater than the implementation limit ({})", msg.dust_limit_satoshis, MAX_DUST_LIMIT_SATOSHIS)));
 853                 }
 854
 855                 // Convert things into internal flags and prep our state:
 856
 857                 let announce = if (msg.channel_flags & 1) == 1 { true } else { false };
 858                 if config.peer_channel_config_limits.force_announced_channel_preference {
 859                         if local_config.announced_channel != announce {
 860                                 return Err(ChannelError::Close("Peer tried to open channel but their announcement preference is different from ours".to_owned()));
 861                         }
 862                 }
 863                 // we either accept their preference or the preferences match
 864                 local_config.announced_channel = announce;
 865
 866                 let background_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background);
 867
 868                 let holder_selected_channel_reserve_satoshis = Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(msg.funding_satoshis);
 869                 if holder_selected_channel_reserve_satoshis < MIN_DUST_LIMIT_SATOSHIS {
 870                         return Err(ChannelError::Close(format!("Suitable channel reserve not found. remote_channel_reserve was ({}). dust_limit_satoshis is ({}).", holder_selected_channel_reserve_satoshis, MIN_DUST_LIMIT_SATOSHIS)));
 871                 }
 872                 if msg.channel_reserve_satoshis < MIN_DUST_LIMIT_SATOSHIS {
 873                         return Err(ChannelError::Close(format!("channel_reserve_satoshis ({}) is smaller than our dust limit ({})", msg.channel_reserve_satoshis, MIN_DUST_LIMIT_SATOSHIS)));
 874                 }
 875                 if holder_selected_channel_reserve_satoshis < msg.dust_limit_satoshis {
 876                         return Err(ChannelError::Close(format!("Dust limit ({}) too high for the channel reserve we require the remote to keep ({})", msg.dust_limit_satoshis, holder_selected_channel_reserve_satoshis)));
 877                 }
 878
 879                 // check if the funder's amount for the initial commitment tx is sufficient
 880                 // for full fee payment
 881                 let funders_amount_msat = msg.funding_satoshis * 1000 - msg.push_msat;
 882                 let lower_limit = background_feerate as u64 * COMMITMENT_TX_BASE_WEIGHT;
 883                 if funders_amount_msat < lower_limit {
 884                         return Err(ChannelError::Close(format!("Insufficient funding amount ({}) for initial commitment. Must be at least {}", funders_amount_msat, lower_limit)));
 885                 }
 886
 887                 let to_local_msat = msg.push_msat;
 888                 let to_remote_msat = funders_amount_msat - background_feerate as u64 * COMMITMENT_TX_BASE_WEIGHT;
 889                 if to_local_msat <= msg.channel_reserve_satoshis * 1000 && to_remote_msat <= holder_selected_channel_reserve_satoshis * 1000 {
 890                         return Err(ChannelError::Close("Insufficient funding amount for initial commitment".to_owned()));
 891                 }
 892
 893                 let counterparty_shutdown_scriptpubkey = if their_features.supports_upfront_shutdown_script() {
 894                         match &msg.shutdown_scriptpubkey {
 895                                 &OptionalField::Present(ref script) => {
 896                                         // Peer is signaling upfront_shutdown and has opt-out with a 0-length script. We don't enforce anything
 897                                         if script.len() == 0 {
 898                                                 None
 899                                         } else {
 900                                                 match ShutdownScript::try_from((script.clone(), their_features)) {
 901                                                         Ok(shutdown_script) => Some(shutdown_script.into_inner()),
 902                                                         Err(_) => return Err(ChannelError::Close(format!("Peer is signaling upfront_shutdown but has provided an unacceptable scriptpubkey format: {}", script))),
 903                                                 }
 904                                         }
 905                                 },
 906                                 // Peer is signaling upfront shutdown but don't opt-out with correct mechanism (a.k.a 0-length script). Peer looks buggy, we fail the channel
 907                                 &OptionalField::Absent => {
 908                                         return Err(ChannelError::Close("Peer is signaling upfront_shutdown but we don't get any script. Use 0-length script to opt-out".to_owned()));
 909                                 }
 910                         }
 911                 } else { None };
 912
 913                 let shutdown_scriptpubkey = if config.channel_options.commit_upfront_shutdown_pubkey {
 914                         Some(keys_provider.get_shutdown_scriptpubkey())
 915                 } else { None };
 916
 917                 if let Some(shutdown_scriptpubkey) = &shutdown_scriptpubkey {
 918                         if !shutdown_scriptpubkey.is_compatible(&their_features) {
 919                                 return Err(ChannelError::Close(format!("Provided a scriptpubkey format not accepted by peer: {}", shutdown_scriptpubkey)));
 920                         }
 921                 }
 922
 923                 let mut secp_ctx = Secp256k1::new();
 924                 secp_ctx.seeded_randomize(&keys_provider.get_secure_random_bytes());
 925
 926                 let chan = Channel {
 927                         user_id,
 928                         config: local_config,
 929
 930                         channel_id: msg.temporary_channel_id,
 931                         channel_state: (ChannelState::OurInitSent as u32) | (ChannelState::TheirInitSent as u32),
 932                         secp_ctx,
 933
 934                         latest_monitor_update_id: 0,
 935
 936                         holder_signer,
 937                         shutdown_scriptpubkey,
 938                         destination_script: keys_provider.get_destination_script(),
 939
 940                         cur_holder_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
 941                         cur_counterparty_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
 942                         value_to_self_msat: msg.push_msat,
 943
 944                         pending_inbound_htlcs: Vec::new(),
 945                         pending_outbound_htlcs: Vec::new(),
 946                         holding_cell_htlc_updates: Vec::new(),
 947                         pending_update_fee: None,
 948                         holding_cell_update_fee: None,
 949                         next_holder_htlc_id: 0,
 950                         next_counterparty_htlc_id: 0,
 951                         update_time_counter: 1,
 952
 953                         resend_order: RAACommitmentOrder::CommitmentFirst,
 954
 955                         monitor_pending_funding_locked: false,
 956                         monitor_pending_revoke_and_ack: false,
 957                         monitor_pending_commitment_signed: false,
 958                         monitor_pending_forwards: Vec::new(),
 959                         monitor_pending_failures: Vec::new(),
 960
 961                         #[cfg(debug_assertions)]
 962                         holder_max_commitment_tx_output: Mutex::new((msg.push_msat, msg.funding_satoshis * 1000 - msg.push_msat)),
 963                         #[cfg(debug_assertions)]
 964                         counterparty_max_commitment_tx_output: Mutex::new((msg.push_msat, msg.funding_satoshis * 1000 - msg.push_msat)),
 965
 966                         last_sent_closing_fee: None,
 967                         pending_counterparty_closing_signed: None,
 968                         closing_fee_limits: None,
 969                         target_closing_feerate_sats_per_kw: None,
 970
 971                         funding_tx_confirmed_in: None,
 972                         funding_tx_confirmation_height: 0,
 973                         short_channel_id: None,
 974
 975                         feerate_per_kw: msg.feerate_per_kw,
 976                         channel_value_satoshis: msg.funding_satoshis,
 977                         counterparty_dust_limit_satoshis: msg.dust_limit_satoshis,
 978                         holder_dust_limit_satoshis: MIN_DUST_LIMIT_SATOSHIS,
 979                         counterparty_max_htlc_value_in_flight_msat: cmp::min(msg.max_htlc_value_in_flight_msat, msg.funding_satoshis * 1000),
 980                         counterparty_selected_channel_reserve_satoshis: Some(msg.channel_reserve_satoshis),
 981                         counterparty_htlc_minimum_msat: msg.htlc_minimum_msat,
 982                         holder_htlc_minimum_msat: if config.own_channel_config.our_htlc_minimum_msat == 0 { 1 } else { config.own_channel_config.our_htlc_minimum_msat },
 983                         counterparty_max_accepted_htlcs: msg.max_accepted_htlcs,
 984                         minimum_depth: Some(config.own_channel_config.minimum_depth),
 985
 986                         counterparty_forwarding_info: None,
 987
 988                         channel_transaction_parameters: ChannelTransactionParameters {
 989                                 holder_pubkeys: pubkeys,
 990                                 holder_selected_contest_delay: config.own_channel_config.our_to_self_delay,
 991                                 is_outbound_from_holder: false,
 992                                 counterparty_parameters: Some(CounterpartyChannelTransactionParameters {
 993                                         selected_contest_delay: msg.to_self_delay,
 994                                         pubkeys: counterparty_pubkeys,
 995                                 }),
 996                                 funding_outpoint: None
 997                         },
 998                         funding_transaction: None,
 999
1000                         counterparty_cur_commitment_point: Some(msg.first_per_commitment_point),
1001                         counterparty_prev_commitment_point: None,
1002                         counterparty_node_id,
1003
1004                         counterparty_shutdown_scriptpubkey,
1005
1006                         commitment_secrets: CounterpartyCommitmentSecrets::new(),
1007
1008                         channel_update_status: ChannelUpdateStatus::Enabled,
1009
1010                         announcement_sigs: None,
1011
1012                         #[cfg(any(test, feature = "fuzztarget"))]
1013                         next_local_commitment_tx_fee_info_cached: Mutex::new(None),
1014                         #[cfg(any(test, feature = "fuzztarget"))]
1015                         next_remote_commitment_tx_fee_info_cached: Mutex::new(None),
1016
1017                         workaround_lnd_bug_4006: None,
1018
1019                         #[cfg(any(test, feature = "fuzztarget"))]
1020                         historical_inbound_htlc_fulfills: HashSet::new(),
1021                 };
1022
1023                 Ok(chan)
1024         }
1025
1026         /// Transaction nomenclature is somewhat confusing here as there are many different cases - a
1027         /// transaction is referred to as "a's transaction" implying that a will be able to broadcast
1028         /// the transaction. Thus, b will generally be sending a signature over such a transaction to
1029         /// a, and a can revoke the transaction by providing b the relevant per_commitment_secret. As
1030         /// such, a transaction is generally the result of b increasing the amount paid to a (or adding
1031         /// an HTLC to a).
1032         /// @local is used only to convert relevant internal structures which refer to remote vs local
1033         /// to decide value of outputs and direction of HTLCs.
1034         /// @generated_by_local is used to determine *which* HTLCs to include - noting that the HTLC
1035         /// state may indicate that one peer has informed the other that they'd like to add an HTLC but
1036         /// have not yet committed it. Such HTLCs will only be included in transactions which are being
1037         /// generated by the peer which proposed adding the HTLCs, and thus we need to understand both
1038         /// which peer generated this transaction and "to whom" this transaction flows.
1039         /// Returns (the transaction info, the number of HTLC outputs which were present in the
1040         /// transaction, the list of HTLCs which were not ignored when building the transaction).
1041         /// Note that below-dust HTLCs are included in the fourth return value, but not the third, and
1042         /// sources are provided only for outbound HTLCs in the fourth return value.
1043         #[inline]
1044         fn build_commitment_transaction<L: Deref>(&self, commitment_number: u64, keys: &TxCreationKeys, local: bool, generated_by_local: bool, logger: &L) -> (CommitmentTransaction, u32, usize, Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)>) where L::Target: Logger {
1045                 let mut included_dust_htlcs: Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)> = Vec::new();
1046                 let num_htlcs = self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len();
1047                 let mut included_non_dust_htlcs: Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)> = Vec::with_capacity(num_htlcs);
1048
1049                 let broadcaster_dust_limit_satoshis = if local { self.holder_dust_limit_satoshis } else { self.counterparty_dust_limit_satoshis };
1050                 let mut remote_htlc_total_msat = 0;
1051                 let mut local_htlc_total_msat = 0;
1052                 let mut value_to_self_msat_offset = 0;
1053
1054                 let mut feerate_per_kw = self.feerate_per_kw;
1055                 if let Some((feerate, update_state)) = self.pending_update_fee {
1056                         if match update_state {
1057                                 // Note that these match the inclusion criteria when scanning
1058                                 // pending_inbound_htlcs below.
1059                                 FeeUpdateState::RemoteAnnounced => { debug_assert!(!self.is_outbound()); !generated_by_local },
1060                                 FeeUpdateState::AwaitingRemoteRevokeToAnnounce => { debug_assert!(!self.is_outbound()); !generated_by_local },
1061                                 FeeUpdateState::Outbound => { assert!(self.is_outbound());  generated_by_local },
1062                         } {
1063                                 feerate_per_kw = feerate;
1064                         }
1065                 }
1066
1067                 log_trace!(logger, "Building commitment transaction number {} (really {} xor {}) for channel {} for {}, generated by {} with fee {}...",
1068                         commitment_number, (INITIAL_COMMITMENT_NUMBER - commitment_number),
1069                         get_commitment_transaction_number_obscure_factor(&self.get_holder_pubkeys().payment_point, &self.get_counterparty_pubkeys().payment_point, self.is_outbound()),
1070                         log_bytes!(self.channel_id), if local { "us" } else { "remote" }, if generated_by_local { "us" } else { "remote" }, feerate_per_kw);
1071
1072                 macro_rules! get_htlc_in_commitment {
1073                         ($htlc: expr, $offered: expr) => {
1074                                 HTLCOutputInCommitment {
1075                                         offered: $offered,
1076                                         amount_msat: $htlc.amount_msat,
1077                                         cltv_expiry: $htlc.cltv_expiry,
1078                                         payment_hash: $htlc.payment_hash,
1079                                         transaction_output_index: None
1080                                 }
1081                         }
1082                 }
1083
1084                 macro_rules! add_htlc_output {
1085                         ($htlc: expr, $outbound: expr, $source: expr, $state_name: expr) => {
1086                                 if $outbound == local { // "offered HTLC output"
1087                                         let htlc_in_tx = get_htlc_in_commitment!($htlc, true);
1088                                         if $htlc.amount_msat / 1000 >= broadcaster_dust_limit_satoshis + (feerate_per_kw as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000) {
1089                                                 log_trace!(logger, "   ...including {} {} HTLC {} (hash {}) with value {}", if $outbound { "outbound" } else { "inbound" }, $state_name, $htlc.htlc_id, log_bytes!($htlc.payment_hash.0), $htlc.amount_msat);
1090                                                 included_non_dust_htlcs.push((htlc_in_tx, $source));
1091                                         } else {
1092                                                 log_trace!(logger, "   ...including {} {} dust HTLC {} (hash {}) with value {} due to dust limit", if $outbound { "outbound" } else { "inbound" }, $state_name, $htlc.htlc_id, log_bytes!($htlc.payment_hash.0), $htlc.amount_msat);
1093                                                 included_dust_htlcs.push((htlc_in_tx, $source));
1094                                         }
1095                                 } else {
1096                                         let htlc_in_tx = get_htlc_in_commitment!($htlc, false);
1097                                         if $htlc.amount_msat / 1000 >= broadcaster_dust_limit_satoshis + (feerate_per_kw as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) {
1098                                                 log_trace!(logger, "   ...including {} {} HTLC {} (hash {}) with value {}", if $outbound { "outbound" } else { "inbound" }, $state_name, $htlc.htlc_id, log_bytes!($htlc.payment_hash.0), $htlc.amount_msat);
1099                                                 included_non_dust_htlcs.push((htlc_in_tx, $source));
1100                                         } else {
1101                                                 log_trace!(logger, "   ...including {} {} dust HTLC {} (hash {}) with value {}", if $outbound { "outbound" } else { "inbound" }, $state_name, $htlc.htlc_id, log_bytes!($htlc.payment_hash.0), $htlc.amount_msat);
1102                                                 included_dust_htlcs.push((htlc_in_tx, $source));
1103                                         }
1104                                 }
1105                         }
1106                 }
1107
1108                 for ref htlc in self.pending_inbound_htlcs.iter() {
1109                         let (include, state_name) = match htlc.state {
1110                                 InboundHTLCState::RemoteAnnounced(_) => (!generated_by_local, "RemoteAnnounced"),
1111                                 InboundHTLCState::AwaitingRemoteRevokeToAnnounce(_) => (!generated_by_local, "AwaitingRemoteRevokeToAnnounce"),
1112                                 InboundHTLCState::AwaitingAnnouncedRemoteRevoke(_) => (true, "AwaitingAnnouncedRemoteRevoke"),
1113                                 InboundHTLCState::Committed => (true, "Committed"),
1114                                 InboundHTLCState::LocalRemoved(_) => (!generated_by_local, "LocalRemoved"),
1115                         };
1116
1117                         if include {
1118                                 add_htlc_output!(htlc, false, None, state_name);
1119                                 remote_htlc_total_msat += htlc.amount_msat;
1120                         } else {
1121                                 log_trace!(logger, "   ...not including inbound HTLC {} (hash {}) with value {} due to state ({})", htlc.htlc_id, log_bytes!(htlc.payment_hash.0), htlc.amount_msat, state_name);
1122                                 match &htlc.state {
1123                                         &InboundHTLCState::LocalRemoved(ref reason) => {
1124                                                 if generated_by_local {
1125                                                         if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
1126                                                                 value_to_self_msat_offset += htlc.amount_msat as i64;
1127                                                         }
1128                                                 }
1129                                         },
1130                                         _ => {},
1131                                 }
1132                         }
1133                 }
1134
1135                 for ref htlc in self.pending_outbound_htlcs.iter() {
1136                         let (include, state_name) = match htlc.state {
1137                                 OutboundHTLCState::LocalAnnounced(_) => (generated_by_local, "LocalAnnounced"),
1138                                 OutboundHTLCState::Committed => (true, "Committed"),
1139                                 OutboundHTLCState::RemoteRemoved(_) => (generated_by_local, "RemoteRemoved"),
1140                                 OutboundHTLCState::AwaitingRemoteRevokeToRemove(_) => (generated_by_local, "AwaitingRemoteRevokeToRemove"),
1141                                 OutboundHTLCState::AwaitingRemovedRemoteRevoke(_) => (false, "AwaitingRemovedRemoteRevoke"),
1142                         };
1143
1144                         if include {
1145                                 add_htlc_output!(htlc, true, Some(&htlc.source), state_name);
1146                                 local_htlc_total_msat += htlc.amount_msat;
1147                         } else {
1148                                 log_trace!(logger, "   ...not including outbound HTLC {} (hash {}) with value {} due to state ({})", htlc.htlc_id, log_bytes!(htlc.payment_hash.0), htlc.amount_msat, state_name);
1149                                 match htlc.state {
1150                                         OutboundHTLCState::AwaitingRemoteRevokeToRemove(None)|OutboundHTLCState::AwaitingRemovedRemoteRevoke(None) => {
1151                                                 value_to_self_msat_offset -= htlc.amount_msat as i64;
1152                                         },
1153                                         OutboundHTLCState::RemoteRemoved(None) => {
1154                                                 if !generated_by_local {
1155                                                         value_to_self_msat_offset -= htlc.amount_msat as i64;
1156                                                 }
1157                                         },
1158                                         _ => {},
1159                                 }
1160                         }
1161                 }
1162
1163                 let value_to_self_msat: i64 = (self.value_to_self_msat - local_htlc_total_msat) as i64 + value_to_self_msat_offset;
1164                 assert!(value_to_self_msat >= 0);
1165                 // Note that in case they have several just-awaiting-last-RAA fulfills in-progress (ie
1166                 // AwaitingRemoteRevokeToRemove or AwaitingRemovedRemoteRevoke) we may have allowed them to
1167                 // "violate" their reserve value by couting those against it. Thus, we have to convert
1168                 // everything to i64 before subtracting as otherwise we can overflow.
1169                 let value_to_remote_msat: i64 = (self.channel_value_satoshis * 1000) as i64 - (self.value_to_self_msat as i64) - (remote_htlc_total_msat as i64) - value_to_self_msat_offset;
1170                 assert!(value_to_remote_msat >= 0);
1171
1172                 #[cfg(debug_assertions)]
1173                 {
1174                         // Make sure that the to_self/to_remote is always either past the appropriate
1175                         // channel_reserve *or* it is making progress towards it.
1176                         let mut broadcaster_max_commitment_tx_output = if generated_by_local {
1177                                 self.holder_max_commitment_tx_output.lock().unwrap()
1178                         } else {
1179                                 self.counterparty_max_commitment_tx_output.lock().unwrap()
1180                         };
1181                         debug_assert!(broadcaster_max_commitment_tx_output.0 <= value_to_self_msat as u64 || value_to_self_msat / 1000 >= self.counterparty_selected_channel_reserve_satoshis.unwrap() as i64);
1182                         broadcaster_max_commitment_tx_output.0 = cmp::max(broadcaster_max_commitment_tx_output.0, value_to_self_msat as u64);
1183                         debug_assert!(broadcaster_max_commitment_tx_output.1 <= value_to_remote_msat as u64 || value_to_remote_msat / 1000 >= Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis) as i64);
1184                         broadcaster_max_commitment_tx_output.1 = cmp::max(broadcaster_max_commitment_tx_output.1, value_to_remote_msat as u64);
1185                 }
1186
1187                 let total_fee = feerate_per_kw as u64 * (COMMITMENT_TX_BASE_WEIGHT + (included_non_dust_htlcs.len() as u64) * COMMITMENT_TX_WEIGHT_PER_HTLC) / 1000;
1188                 let (value_to_self, value_to_remote) = if self.is_outbound() {
1189                         (value_to_self_msat / 1000 - total_fee as i64, value_to_remote_msat / 1000)
1190                 } else {
1191                         (value_to_self_msat / 1000, value_to_remote_msat / 1000 - total_fee as i64)
1192                 };
1193
1194                 let mut value_to_a = if local { value_to_self } else { value_to_remote };
1195                 let mut value_to_b = if local { value_to_remote } else { value_to_self };
1196
1197                 if value_to_a >= (broadcaster_dust_limit_satoshis as i64) {
1198                         log_trace!(logger, "   ...including {} output with value {}", if local { "to_local" } else { "to_remote" }, value_to_a);
1199                 } else {
1200                         value_to_a = 0;
1201                 }
1202
1203                 if value_to_b >= (broadcaster_dust_limit_satoshis as i64) {
1204                         log_trace!(logger, "   ...including {} output with value {}", if local { "to_remote" } else { "to_local" }, value_to_b);
1205                 } else {
1206                         value_to_b = 0;
1207                 }
1208
1209                 let num_nondust_htlcs = included_non_dust_htlcs.len();
1210
1211                 let channel_parameters =
1212                         if local { self.channel_transaction_parameters.as_holder_broadcastable() }
1213                         else { self.channel_transaction_parameters.as_counterparty_broadcastable() };
1214                 let tx = CommitmentTransaction::new_with_auxiliary_htlc_data(commitment_number,
1215                                                                              value_to_a as u64,
1216                                                                              value_to_b as u64,
1217                                                                              keys.clone(),
1218                                                                              feerate_per_kw,
1219                                                                              &mut included_non_dust_htlcs,
1220                                                                              &channel_parameters
1221                 );
1222                 let mut htlcs_included = included_non_dust_htlcs;
1223                 // The unwrap is safe, because all non-dust HTLCs have been assigned an output index
1224                 htlcs_included.sort_unstable_by_key(|h| h.0.transaction_output_index.unwrap());
1225                 htlcs_included.append(&mut included_dust_htlcs);
1226
1227                 (tx, feerate_per_kw, num_nondust_htlcs, htlcs_included)
1228         }
1229
1230         #[inline]
1231         fn get_closing_scriptpubkey(&self) -> Script {
1232                 // The shutdown scriptpubkey is set on channel opening when option_upfront_shutdown_script
1233                 // is signaled. Otherwise, it is set when sending a shutdown message. Calling this method
1234                 // outside of those situations will fail.
1235                 self.shutdown_scriptpubkey.clone().unwrap().into_inner()
1236         }
1237
1238         #[inline]
1239         fn get_closing_transaction_weight(&self, a_scriptpubkey: Option<&Script>, b_scriptpubkey: Option<&Script>) -> u64 {
1240                 let mut ret =
1241                 (4 +                                           // version
1242                  1 +                                           // input count
1243                  36 +                                          // prevout
1244                  1 +                                           // script length (0)
1245                  4 +                                           // sequence
1246                  1 +                                           // output count
1247                  4                                             // lock time
1248                  )*4 +                                         // * 4 for non-witness parts
1249                 2 +                                            // witness marker and flag
1250                 1 +                                            // witness element count
1251                 4 +                                            // 4 element lengths (2 sigs, multisig dummy, and witness script)
1252                 self.get_funding_redeemscript().len() as u64 + // funding witness script
1253                 2*(1 + 71);                                    // two signatures + sighash type flags
1254                 if let Some(spk) = a_scriptpubkey {
1255                         ret += ((8+1) +                            // output values and script length
1256                                 spk.len() as u64) * 4;                 // scriptpubkey and witness multiplier
1257                 }
1258                 if let Some(spk) = b_scriptpubkey {
1259                         ret += ((8+1) +                            // output values and script length
1260                                 spk.len() as u64) * 4;                 // scriptpubkey and witness multiplier
1261                 }
1262                 ret
1263         }
1264
1265         #[inline]
1266         fn build_closing_transaction(&self, proposed_total_fee_satoshis: u64, skip_remote_output: bool) -> (Transaction, u64) {
1267                 let txins = {
1268                         let mut ins: Vec<TxIn> = Vec::new();
1269                         ins.push(TxIn {
1270                                 previous_output: self.funding_outpoint().into_bitcoin_outpoint(),
1271                                 script_sig: Script::new(),
1272                                 sequence: 0xffffffff,
1273                                 witness: Vec::new(),
1274                         });
1275                         ins
1276                 };
1277
1278                 assert!(self.pending_inbound_htlcs.is_empty());
1279                 assert!(self.pending_outbound_htlcs.is_empty());
1280                 assert!(self.pending_update_fee.is_none());
1281                 let mut txouts: Vec<(TxOut, ())> = Vec::new();
1282
1283                 let mut total_fee_satoshis = proposed_total_fee_satoshis;
1284                 let value_to_self: i64 = (self.value_to_self_msat as i64) / 1000 - if self.is_outbound() { total_fee_satoshis as i64 } else { 0 };
1285                 let value_to_remote: i64 = ((self.channel_value_satoshis * 1000 - self.value_to_self_msat) as i64 / 1000) - if self.is_outbound() { 0 } else { total_fee_satoshis as i64 };
1286
1287                 if value_to_self < 0 {
1288                         assert!(self.is_outbound());
1289                         total_fee_satoshis += (-value_to_self) as u64;
1290                 } else if value_to_remote < 0 {
1291                         assert!(!self.is_outbound());
1292                         total_fee_satoshis += (-value_to_remote) as u64;
1293                 }
1294
1295                 if !skip_remote_output && value_to_remote as u64 > self.holder_dust_limit_satoshis {
1296                         txouts.push((TxOut {
1297                                 script_pubkey: self.counterparty_shutdown_scriptpubkey.clone().unwrap(),
1298                                 value: value_to_remote as u64
1299                         }, ()));
1300                 }
1301
1302                 assert!(self.shutdown_scriptpubkey.is_some());
1303                 if value_to_self as u64 > self.holder_dust_limit_satoshis {
1304                         txouts.push((TxOut {
1305                                 script_pubkey: self.get_closing_scriptpubkey(),
1306                                 value: value_to_self as u64
1307                         }, ()));
1308                 }
1309
1310                 transaction_utils::sort_outputs(&mut txouts, |_, _| { cmp::Ordering::Equal }); // Ordering doesnt matter if they used our pubkey...
1311
1312                 let mut outputs: Vec<TxOut> = Vec::new();
1313                 for out in txouts.drain(..) {
1314                         outputs.push(out.0);
1315                 }
1316
1317                 (Transaction {
1318                         version: 2,
1319                         lock_time: 0,
1320                         input: txins,
1321                         output: outputs,
1322                 }, total_fee_satoshis)
1323         }
1324
1325         fn funding_outpoint(&self) -> OutPoint {
1326                 self.channel_transaction_parameters.funding_outpoint.unwrap()
1327         }
1328
1329         #[inline]
1330         /// Creates a set of keys for build_commitment_transaction to generate a transaction which our
1331         /// counterparty will sign (ie DO NOT send signatures over a transaction created by this to
1332         /// our counterparty!)
1333         /// The result is a transaction which we can revoke broadcastership of (ie a "local" transaction)
1334         /// TODO Some magic rust shit to compile-time check this?
1335         fn build_holder_transaction_keys(&self, commitment_number: u64) -> Result<TxCreationKeys, ChannelError> {
1336                 let per_commitment_point = self.holder_signer.get_per_commitment_point(commitment_number, &self.secp_ctx);
1337                 let delayed_payment_base = &self.get_holder_pubkeys().delayed_payment_basepoint;
1338                 let htlc_basepoint = &self.get_holder_pubkeys().htlc_basepoint;
1339                 let counterparty_pubkeys = self.get_counterparty_pubkeys();
1340
1341                 Ok(secp_check!(TxCreationKeys::derive_new(&self.secp_ctx, &per_commitment_point, delayed_payment_base, htlc_basepoint, &counterparty_pubkeys.revocation_basepoint, &counterparty_pubkeys.htlc_basepoint), "Local tx keys generation got bogus keys".to_owned()))
1342         }
1343
1344         #[inline]
1345         /// Creates a set of keys for build_commitment_transaction to generate a transaction which we
1346         /// will sign and send to our counterparty.
1347         /// If an Err is returned, it is a ChannelError::Close (for get_outbound_funding_created)
1348         fn build_remote_transaction_keys(&self) -> Result<TxCreationKeys, ChannelError> {
1349                 //TODO: Ensure that the payment_key derived here ends up in the library users' wallet as we
1350                 //may see payments to it!
1351                 let revocation_basepoint = &self.get_holder_pubkeys().revocation_basepoint;
1352                 let htlc_basepoint = &self.get_holder_pubkeys().htlc_basepoint;
1353                 let counterparty_pubkeys = self.get_counterparty_pubkeys();
1354
1355                 Ok(secp_check!(TxCreationKeys::derive_new(&self.secp_ctx, &self.counterparty_cur_commitment_point.unwrap(), &counterparty_pubkeys.delayed_payment_basepoint, &counterparty_pubkeys.htlc_basepoint, revocation_basepoint, htlc_basepoint), "Remote tx keys generation got bogus keys".to_owned()))
1356         }
1357
1358         /// Gets the redeemscript for the funding transaction output (ie the funding transaction output
1359         /// pays to get_funding_redeemscript().to_v0_p2wsh()).
1360         /// Panics if called before accept_channel/new_from_req
1361         pub fn get_funding_redeemscript(&self) -> Script {
1362                 make_funding_redeemscript(&self.get_holder_pubkeys().funding_pubkey, self.counterparty_funding_pubkey())
1363         }
1364
1365         fn get_update_fulfill_htlc<L: Deref>(&mut self, htlc_id_arg: u64, payment_preimage_arg: PaymentPreimage, logger: &L) -> UpdateFulfillFetch where L::Target: Logger {
1366                 // Either ChannelFunded got set (which means it won't be unset) or there is no way any
1367                 // caller thought we could have something claimed (cause we wouldn't have accepted in an
1368                 // incoming HTLC anyway). If we got to ShutdownComplete, callers aren't allowed to call us,
1369                 // either.
1370                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
1371                         panic!("Was asked to fulfill an HTLC when channel was not in an operational state");
1372                 }
1373                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
1374
1375                 let payment_hash_calc = PaymentHash(Sha256::hash(&payment_preimage_arg.0[..]).into_inner());
1376
1377                 // ChannelManager may generate duplicate claims/fails due to HTLC update events from
1378                 // on-chain ChannelsMonitors during block rescan. Ideally we'd figure out a way to drop
1379                 // these, but for now we just have to treat them as normal.
1380
1381                 let mut pending_idx = core::usize::MAX;
1382                 let mut htlc_value_msat = 0;
1383                 for (idx, htlc) in self.pending_inbound_htlcs.iter().enumerate() {
1384                         if htlc.htlc_id == htlc_id_arg {
1385                                 assert_eq!(htlc.payment_hash, payment_hash_calc);
1386                                 match htlc.state {
1387                                         InboundHTLCState::Committed => {},
1388                                         InboundHTLCState::LocalRemoved(ref reason) => {
1389                                                 if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
1390                                                 } else {
1391                                                         log_warn!(logger, "Have preimage and want to fulfill HTLC with payment hash {} we already failed against channel {}", log_bytes!(htlc.payment_hash.0), log_bytes!(self.channel_id()));
1392                                                         debug_assert!(false, "Tried to fulfill an HTLC that was already failed");
1393                                                 }
1394                                                 return UpdateFulfillFetch::DuplicateClaim {};
1395                                         },
1396                                         _ => {
1397                                                 debug_assert!(false, "Have an inbound HTLC we tried to claim before it was fully committed to");
1398                                                 // Don't return in release mode here so that we can update channel_monitor
1399                                         }
1400                                 }
1401                                 pending_idx = idx;
1402                                 htlc_value_msat = htlc.amount_msat;
1403                                 break;
1404                         }
1405                 }
1406                 if pending_idx == core::usize::MAX {
1407                         #[cfg(any(test, feature = "fuzztarget"))]
1408                         // If we failed to find an HTLC to fulfill, make sure it was previously fulfilled and
1409                         // this is simply a duplicate claim, not previously failed and we lost funds.
1410                         debug_assert!(self.historical_inbound_htlc_fulfills.contains(&htlc_id_arg));
1411                         return UpdateFulfillFetch::DuplicateClaim {};
1412                 }
1413
1414                 // Now update local state:
1415                 //
1416                 // We have to put the payment_preimage in the channel_monitor right away here to ensure we
1417                 // can claim it even if the channel hits the chain before we see their next commitment.
1418                 self.latest_monitor_update_id += 1;
1419                 let monitor_update = ChannelMonitorUpdate {
1420                         update_id: self.latest_monitor_update_id,
1421                         updates: vec![ChannelMonitorUpdateStep::PaymentPreimage {
1422                                 payment_preimage: payment_preimage_arg.clone(),
1423                         }],
1424                 };
1425
1426                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32)) != 0 {
1427                         for pending_update in self.holding_cell_htlc_updates.iter() {
1428                                 match pending_update {
1429                                         &HTLCUpdateAwaitingACK::ClaimHTLC { htlc_id, .. } => {
1430                                                 if htlc_id_arg == htlc_id {
1431                                                         // Make sure we don't leave latest_monitor_update_id incremented here:
1432                                                         self.latest_monitor_update_id -= 1;
1433                                                         #[cfg(any(test, feature = "fuzztarget"))]
1434                                                         debug_assert!(self.historical_inbound_htlc_fulfills.contains(&htlc_id_arg));
1435                                                         return UpdateFulfillFetch::DuplicateClaim {};
1436                                                 }
1437                                         },
1438                                         &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, .. } => {
1439                                                 if htlc_id_arg == htlc_id {
1440                                                         log_warn!(logger, "Have preimage and want to fulfill HTLC with pending failure against channel {}", log_bytes!(self.channel_id()));
1441                                                         // TODO: We may actually be able to switch to a fulfill here, though its
1442                                                         // rare enough it may not be worth the complexity burden.
1443                                                         debug_assert!(false, "Tried to fulfill an HTLC that was already failed");
1444                                                         return UpdateFulfillFetch::NewClaim { monitor_update, htlc_value_msat, msg: None };
1445                                                 }
1446                                         },
1447                                         _ => {}
1448                                 }
1449                         }
1450                         log_trace!(logger, "Adding HTLC claim to holding_cell in channel {}! Current state: {}", log_bytes!(self.channel_id()), self.channel_state);
1451                         self.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::ClaimHTLC {
1452                                 payment_preimage: payment_preimage_arg, htlc_id: htlc_id_arg,
1453                         });
1454                         #[cfg(any(test, feature = "fuzztarget"))]
1455                         self.historical_inbound_htlc_fulfills.insert(htlc_id_arg);
1456                         return UpdateFulfillFetch::NewClaim { monitor_update, htlc_value_msat, msg: None };
1457                 }
1458                 #[cfg(any(test, feature = "fuzztarget"))]
1459                 self.historical_inbound_htlc_fulfills.insert(htlc_id_arg);
1460
1461                 {
1462                         let htlc = &mut self.pending_inbound_htlcs[pending_idx];
1463                         if let InboundHTLCState::Committed = htlc.state {
1464                         } else {
1465                                 debug_assert!(false, "Have an inbound HTLC we tried to claim before it was fully committed to");
1466                                 return UpdateFulfillFetch::NewClaim { monitor_update, htlc_value_msat, msg: None };
1467                         }
1468                         log_trace!(logger, "Upgrading HTLC {} to LocalRemoved with a Fulfill in channel {}!", log_bytes!(htlc.payment_hash.0), log_bytes!(self.channel_id));
1469                         htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::Fulfill(payment_preimage_arg.clone()));
1470                 }
1471
1472                 UpdateFulfillFetch::NewClaim {
1473                         monitor_update,
1474                         htlc_value_msat,
1475                         msg: Some(msgs::UpdateFulfillHTLC {
1476                                 channel_id: self.channel_id(),
1477                                 htlc_id: htlc_id_arg,
1478                                 payment_preimage: payment_preimage_arg,
1479                         }),
1480                 }
1481         }
1482
1483         pub fn get_update_fulfill_htlc_and_commit<L: Deref>(&mut self, htlc_id: u64, payment_preimage: PaymentPreimage, logger: &L) -> Result<UpdateFulfillCommitFetch, (ChannelError, ChannelMonitorUpdate)> where L::Target: Logger {
1484                 match self.get_update_fulfill_htlc(htlc_id, payment_preimage, logger) {
1485                         UpdateFulfillFetch::NewClaim { mut monitor_update, htlc_value_msat, msg: Some(update_fulfill_htlc) } => {
1486                                 let (commitment, mut additional_update) = match self.send_commitment_no_status_check(logger) {
1487                                         Err(e) => return Err((e, monitor_update)),
1488                                         Ok(res) => res
1489                                 };
1490                                 // send_commitment_no_status_check may bump latest_monitor_id but we want them to be
1491                                 // strictly increasing by one, so decrement it here.
1492                                 self.latest_monitor_update_id = monitor_update.update_id;
1493                                 monitor_update.updates.append(&mut additional_update.updates);
1494                                 Ok(UpdateFulfillCommitFetch::NewClaim { monitor_update, htlc_value_msat, msgs: Some((update_fulfill_htlc, commitment)) })
1495                         },
1496                         UpdateFulfillFetch::NewClaim { monitor_update, htlc_value_msat, msg: None } =>
1497                                 Ok(UpdateFulfillCommitFetch::NewClaim { monitor_update, htlc_value_msat, msgs: None }),
1498                         UpdateFulfillFetch::DuplicateClaim {} => Ok(UpdateFulfillCommitFetch::DuplicateClaim {}),
1499                 }
1500         }
1501
1502         /// We can only have one resolution per HTLC. In some cases around reconnect, we may fulfill
1503         /// an HTLC more than once or fulfill once and then attempt to fail after reconnect. We cannot,
1504         /// however, fail more than once as we wait for an upstream failure to be irrevocably committed
1505         /// before we fail backwards.
1506         /// If we do fail twice, we debug_assert!(false) and return Ok(None). Thus, will always return
1507         /// Ok(_) if debug assertions are turned on or preconditions are met.
1508         pub fn get_update_fail_htlc<L: Deref>(&mut self, htlc_id_arg: u64, err_packet: msgs::OnionErrorPacket, logger: &L) -> Result<Option<msgs::UpdateFailHTLC>, ChannelError> where L::Target: Logger {
1509                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
1510                         panic!("Was asked to fail an HTLC when channel was not in an operational state");
1511                 }
1512                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
1513
1514                 // ChannelManager may generate duplicate claims/fails due to HTLC update events from
1515                 // on-chain ChannelsMonitors during block rescan. Ideally we'd figure out a way to drop
1516                 // these, but for now we just have to treat them as normal.
1517
1518                 let mut pending_idx = core::usize::MAX;
1519                 for (idx, htlc) in self.pending_inbound_htlcs.iter().enumerate() {
1520                         if htlc.htlc_id == htlc_id_arg {
1521                                 match htlc.state {
1522                                         InboundHTLCState::Committed => {},
1523                                         InboundHTLCState::LocalRemoved(ref reason) => {
1524                                                 if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
1525                                                 } else {
1526                                                         debug_assert!(false, "Tried to fail an HTLC that was already failed");
1527                                                 }
1528                                                 return Ok(None);
1529                                         },
1530                                         _ => {
1531                                                 debug_assert!(false, "Have an inbound HTLC we tried to claim before it was fully committed to");
1532                                                 return Err(ChannelError::Ignore(format!("Unable to find a pending HTLC which matched the given HTLC ID ({})", htlc.htlc_id)));
1533                                         }
1534                                 }
1535                                 pending_idx = idx;
1536                         }
1537                 }
1538                 if pending_idx == core::usize::MAX {
1539                         #[cfg(any(test, feature = "fuzztarget"))]
1540                         // If we failed to find an HTLC to fail, make sure it was previously fulfilled and this
1541                         // is simply a duplicate fail, not previously failed and we failed-back too early.
1542                         debug_assert!(self.historical_inbound_htlc_fulfills.contains(&htlc_id_arg));
1543                         return Ok(None);
1544                 }
1545
1546                 // Now update local state:
1547                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32)) != 0 {
1548                         for pending_update in self.holding_cell_htlc_updates.iter() {
1549                                 match pending_update {
1550                                         &HTLCUpdateAwaitingACK::ClaimHTLC { htlc_id, .. } => {
1551                                                 if htlc_id_arg == htlc_id {
1552                                                         #[cfg(any(test, feature = "fuzztarget"))]
1553                                                         debug_assert!(self.historical_inbound_htlc_fulfills.contains(&htlc_id_arg));
1554                                                         return Ok(None);
1555                                                 }
1556                                         },
1557                                         &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, .. } => {
1558                                                 if htlc_id_arg == htlc_id {
1559                                                         debug_assert!(false, "Tried to fail an HTLC that was already failed");
1560                                                         return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID".to_owned()));
1561                                                 }
1562                                         },
1563                                         _ => {}
1564                                 }
1565                         }
1566                         log_trace!(logger, "Placing failure for HTLC ID {} in holding cell in channel {}.", htlc_id_arg, log_bytes!(self.channel_id()));
1567                         self.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::FailHTLC {
1568                                 htlc_id: htlc_id_arg,
1569                                 err_packet,
1570                         });
1571                         return Ok(None);
1572                 }
1573
1574                 log_trace!(logger, "Failing HTLC ID {} back with a update_fail_htlc message in channel {}.", htlc_id_arg, log_bytes!(self.channel_id()));
1575                 {
1576                         let htlc = &mut self.pending_inbound_htlcs[pending_idx];
1577                         htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::FailRelay(err_packet.clone()));
1578                 }
1579
1580                 Ok(Some(msgs::UpdateFailHTLC {
1581                         channel_id: self.channel_id(),
1582                         htlc_id: htlc_id_arg,
1583                         reason: err_packet
1584                 }))
1585         }
1586
1587         // Message handlers:
1588
1589         pub fn accept_channel(&mut self, msg: &msgs::AcceptChannel, config: &UserConfig, their_features: &InitFeatures) -> Result<(), ChannelError> {
1590                 // Check sanity of message fields:
1591                 if !self.is_outbound() {
1592                         return Err(ChannelError::Close("Got an accept_channel message from an inbound peer".to_owned()));
1593                 }
1594                 if self.channel_state != ChannelState::OurInitSent as u32 {
1595                         return Err(ChannelError::Close("Got an accept_channel message at a strange time".to_owned()));
1596                 }
1597                 if msg.dust_limit_satoshis > 21000000 * 100000000 {
1598                         return Err(ChannelError::Close(format!("Peer never wants payout outputs? dust_limit_satoshis was {}", msg.dust_limit_satoshis)));
1599                 }
1600                 if msg.channel_reserve_satoshis > self.channel_value_satoshis {
1601                         return Err(ChannelError::Close(format!("Bogus channel_reserve_satoshis ({}). Must not be greater than ({})", msg.channel_reserve_satoshis, self.channel_value_satoshis)));
1602                 }
1603                 if msg.channel_reserve_satoshis < self.holder_dust_limit_satoshis {
1604                         return Err(ChannelError::Close(format!("Peer never wants payout outputs? channel_reserve_satoshis was ({}). dust_limit is ({})", msg.channel_reserve_satoshis, self.holder_dust_limit_satoshis)));
1605                 }
1606                 let remote_reserve = Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis);
1607                 if msg.dust_limit_satoshis > remote_reserve {
1608                         return Err(ChannelError::Close(format!("Dust limit ({}) is bigger than our channel reserve ({})", msg.dust_limit_satoshis, remote_reserve)));
1609                 }
1610                 let full_channel_value_msat = (self.channel_value_satoshis - msg.channel_reserve_satoshis) * 1000;
1611                 if msg.htlc_minimum_msat >= full_channel_value_msat {
1612                         return Err(ChannelError::Close(format!("Minimum htlc value ({}) is full channel value ({})", msg.htlc_minimum_msat, full_channel_value_msat)));
1613                 }
1614                 let max_delay_acceptable = u16::min(config.peer_channel_config_limits.their_to_self_delay, MAX_LOCAL_BREAKDOWN_TIMEOUT);
1615                 if msg.to_self_delay > max_delay_acceptable {
1616                         return Err(ChannelError::Close(format!("They wanted our payments to be delayed by a needlessly long period. Upper limit: {}. Actual: {}", max_delay_acceptable, msg.to_self_delay)));
1617                 }
1618                 if msg.max_accepted_htlcs < 1 {
1619                         return Err(ChannelError::Close("0 max_accepted_htlcs makes for a useless channel".to_owned()));
1620                 }
1621                 if msg.max_accepted_htlcs > MAX_HTLCS {
1622                         return Err(ChannelError::Close(format!("max_accepted_htlcs was {}. It must not be larger than {}", msg.max_accepted_htlcs, MAX_HTLCS)));
1623                 }
1624
1625                 // Now check against optional parameters as set by config...
1626                 if msg.htlc_minimum_msat > config.peer_channel_config_limits.max_htlc_minimum_msat {
1627                         return Err(ChannelError::Close(format!("htlc_minimum_msat ({}) is higher than the user specified limit ({})", msg.htlc_minimum_msat, config.peer_channel_config_limits.max_htlc_minimum_msat)));
1628                 }
1629                 if msg.max_htlc_value_in_flight_msat < config.peer_channel_config_limits.min_max_htlc_value_in_flight_msat {
1630                         return Err(ChannelError::Close(format!("max_htlc_value_in_flight_msat ({}) is less than the user specified limit ({})", msg.max_htlc_value_in_flight_msat, config.peer_channel_config_limits.min_max_htlc_value_in_flight_msat)));
1631                 }
1632                 if msg.channel_reserve_satoshis > config.peer_channel_config_limits.max_channel_reserve_satoshis {
1633                         return Err(ChannelError::Close(format!("channel_reserve_satoshis ({}) is higher than the user specified limit ({})", msg.channel_reserve_satoshis, config.peer_channel_config_limits.max_channel_reserve_satoshis)));
1634                 }
1635                 if msg.max_accepted_htlcs < config.peer_channel_config_limits.min_max_accepted_htlcs {
1636                         return Err(ChannelError::Close(format!("max_accepted_htlcs ({}) is less than the user specified limit ({})", msg.max_accepted_htlcs, config.peer_channel_config_limits.min_max_accepted_htlcs)));
1637                 }
1638                 if msg.dust_limit_satoshis < MIN_DUST_LIMIT_SATOSHIS {
1639                         return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is less than the implementation limit ({})", msg.dust_limit_satoshis, MIN_DUST_LIMIT_SATOSHIS)));
1640                 }
1641                 if msg.dust_limit_satoshis > MAX_DUST_LIMIT_SATOSHIS {
1642                         return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is greater than the implementation limit ({})", msg.dust_limit_satoshis, MAX_DUST_LIMIT_SATOSHIS)));
1643                 }
1644                 if msg.minimum_depth > config.peer_channel_config_limits.max_minimum_depth {
1645                         return Err(ChannelError::Close(format!("We consider the minimum depth to be unreasonably large. Expected minimum: ({}). Actual: ({})", config.peer_channel_config_limits.max_minimum_depth, msg.minimum_depth)));
1646                 }
1647                 if msg.minimum_depth == 0 {
1648                         // Note that if this changes we should update the serialization minimum version to
1649                         // indicate to older clients that they don't understand some features of the current
1650                         // channel.
1651                         return Err(ChannelError::Close("Minimum confirmation depth must be at least 1".to_owned()));
1652                 }
1653
1654                 let counterparty_shutdown_scriptpubkey = if their_features.supports_upfront_shutdown_script() {
1655                         match &msg.shutdown_scriptpubkey {
1656                                 &OptionalField::Present(ref script) => {
1657                                         // Peer is signaling upfront_shutdown and has opt-out with a 0-length script. We don't enforce anything
1658                                         if script.len() == 0 {
1659                                                 None
1660                                         } else {
1661                                                 match ShutdownScript::try_from((script.clone(), their_features)) {
1662                                                         Ok(shutdown_script) => Some(shutdown_script.into_inner()),
1663                                                         Err(_) => return Err(ChannelError::Close(format!("Peer is signaling upfront_shutdown but has provided an unacceptable scriptpubkey format: {}", script))),
1664                                                 }
1665                                         }
1666                                 },
1667                                 // Peer is signaling upfront shutdown but don't opt-out with correct mechanism (a.k.a 0-length script). Peer looks buggy, we fail the channel
1668                                 &OptionalField::Absent => {
1669                                         return Err(ChannelError::Close("Peer is signaling upfront_shutdown but we don't get any script. Use 0-length script to opt-out".to_owned()));
1670                                 }
1671                         }
1672                 } else { None };
1673
1674                 self.counterparty_dust_limit_satoshis = msg.dust_limit_satoshis;
1675                 self.counterparty_max_htlc_value_in_flight_msat = cmp::min(msg.max_htlc_value_in_flight_msat, self.channel_value_satoshis * 1000);
1676                 self.counterparty_selected_channel_reserve_satoshis = Some(msg.channel_reserve_satoshis);
1677                 self.counterparty_htlc_minimum_msat = msg.htlc_minimum_msat;
1678                 self.counterparty_max_accepted_htlcs = msg.max_accepted_htlcs;
1679                 self.minimum_depth = Some(msg.minimum_depth);
1680
1681                 let counterparty_pubkeys = ChannelPublicKeys {
1682                         funding_pubkey: msg.funding_pubkey,
1683                         revocation_basepoint: msg.revocation_basepoint,
1684                         payment_point: msg.payment_point,
1685                         delayed_payment_basepoint: msg.delayed_payment_basepoint,
1686                         htlc_basepoint: msg.htlc_basepoint
1687                 };
1688
1689                 self.channel_transaction_parameters.counterparty_parameters = Some(CounterpartyChannelTransactionParameters {
1690                         selected_contest_delay: msg.to_self_delay,
1691                         pubkeys: counterparty_pubkeys,
1692                 });
1693
1694                 self.counterparty_cur_commitment_point = Some(msg.first_per_commitment_point);
1695                 self.counterparty_shutdown_scriptpubkey = counterparty_shutdown_scriptpubkey;
1696
1697                 self.channel_state = ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32;
1698
1699                 Ok(())
1700         }
1701
1702         fn funding_created_signature<L: Deref>(&mut self, sig: &Signature, logger: &L) -> Result<(Txid, CommitmentTransaction, Signature), ChannelError> where L::Target: Logger {
1703                 let funding_script = self.get_funding_redeemscript();
1704
1705                 let keys = self.build_holder_transaction_keys(self.cur_holder_commitment_transaction_number)?;
1706                 let initial_commitment_tx = self.build_commitment_transaction(self.cur_holder_commitment_transaction_number, &keys, true, false, logger).0;
1707                 {
1708                         let trusted_tx = initial_commitment_tx.trust();
1709                         let initial_commitment_bitcoin_tx = trusted_tx.built_transaction();
1710                         let sighash = initial_commitment_bitcoin_tx.get_sighash_all(&funding_script, self.channel_value_satoshis);
1711                         // They sign the holder commitment transaction...
1712                         log_trace!(logger, "Checking funding_created tx signature {} by key {} against tx {} (sighash {}) with redeemscript {} for channel {}.",
1713                                 log_bytes!(sig.serialize_compact()[..]), log_bytes!(self.counterparty_funding_pubkey().serialize()),
1714                                 encode::serialize_hex(&initial_commitment_bitcoin_tx.transaction), log_bytes!(sighash[..]),
1715                                 encode::serialize_hex(&funding_script), log_bytes!(self.channel_id()));
1716                         secp_check!(self.secp_ctx.verify(&sighash, &sig, self.counterparty_funding_pubkey()), "Invalid funding_created signature from peer".to_owned());
1717                 }
1718
1719                 let counterparty_keys = self.build_remote_transaction_keys()?;
1720                 let counterparty_initial_commitment_tx = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, false, logger).0;
1721
1722                 let counterparty_trusted_tx = counterparty_initial_commitment_tx.trust();
1723                 let counterparty_initial_bitcoin_tx = counterparty_trusted_tx.built_transaction();
1724                 log_trace!(logger, "Initial counterparty tx for channel {} is: txid {} tx {}",
1725                         log_bytes!(self.channel_id()), counterparty_initial_bitcoin_tx.txid, encode::serialize_hex(&counterparty_initial_bitcoin_tx.transaction));
1726
1727                 let counterparty_signature = self.holder_signer.sign_counterparty_commitment(&counterparty_initial_commitment_tx, &self.secp_ctx)
1728                                 .map_err(|_| ChannelError::Close("Failed to get signatures for new commitment_signed".to_owned()))?.0;
1729
1730                 // We sign "counterparty" commitment transaction, allowing them to broadcast the tx if they wish.
1731                 Ok((counterparty_initial_bitcoin_tx.txid, initial_commitment_tx, counterparty_signature))
1732         }
1733
1734         fn counterparty_funding_pubkey(&self) -> &PublicKey {
1735                 &self.get_counterparty_pubkeys().funding_pubkey
1736         }
1737
1738         pub fn funding_created<L: Deref>(&mut self, msg: &msgs::FundingCreated, best_block: BestBlock, logger: &L) -> Result<(msgs::FundingSigned, ChannelMonitor<Signer>), ChannelError> where L::Target: Logger {
1739                 if self.is_outbound() {
1740                         return Err(ChannelError::Close("Received funding_created for an outbound channel?".to_owned()));
1741                 }
1742                 if self.channel_state != (ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32) {
1743                         // BOLT 2 says that if we disconnect before we send funding_signed we SHOULD NOT
1744                         // remember the channel, so it's safe to just send an error_message here and drop the
1745                         // channel.
1746                         return Err(ChannelError::Close("Received funding_created after we got the channel!".to_owned()));
1747                 }
1748                 if self.commitment_secrets.get_min_seen_secret() != (1 << 48) ||
1749                                 self.cur_counterparty_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER ||
1750                                 self.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
1751                         panic!("Should not have advanced channel commitment tx numbers prior to funding_created");
1752                 }
1753
1754                 let funding_txo = OutPoint { txid: msg.funding_txid, index: msg.funding_output_index };
1755                 self.channel_transaction_parameters.funding_outpoint = Some(funding_txo);
1756                 // This is an externally observable change before we finish all our checks.  In particular
1757                 // funding_created_signature may fail.
1758                 self.holder_signer.ready_channel(&self.channel_transaction_parameters);
1759
1760                 let (counterparty_initial_commitment_txid, initial_commitment_tx, signature) = match self.funding_created_signature(&msg.signature, logger) {
1761                         Ok(res) => res,
1762                         Err(ChannelError::Close(e)) => {
1763                                 self.channel_transaction_parameters.funding_outpoint = None;
1764                                 return Err(ChannelError::Close(e));
1765                         },
1766                         Err(e) => {
1767                                 // The only error we know how to handle is ChannelError::Close, so we fall over here
1768                                 // to make sure we don't continue with an inconsistent state.
1769                                 panic!("unexpected error type from funding_created_signature {:?}", e);
1770                         }
1771                 };
1772
1773                 let holder_commitment_tx = HolderCommitmentTransaction::new(
1774                         initial_commitment_tx,
1775                         msg.signature,
1776                         Vec::new(),
1777                         &self.get_holder_pubkeys().funding_pubkey,
1778                         self.counterparty_funding_pubkey()
1779                 );
1780
1781                 // Now that we're past error-generating stuff, update our local state:
1782
1783                 let funding_redeemscript = self.get_funding_redeemscript();
1784                 let funding_txo_script = funding_redeemscript.to_v0_p2wsh();
1785                 let obscure_factor = get_commitment_transaction_number_obscure_factor(&self.get_holder_pubkeys().payment_point, &self.get_counterparty_pubkeys().payment_point, self.is_outbound());
1786                 let shutdown_script = self.shutdown_scriptpubkey.clone().map(|script| script.into_inner());
1787                 let channel_monitor = ChannelMonitor::new(self.secp_ctx.clone(), self.holder_signer.clone(),
1788                                                           shutdown_script, self.get_holder_selected_contest_delay(),
1789                                                           &self.destination_script, (funding_txo, funding_txo_script.clone()),
1790                                                           &self.channel_transaction_parameters,
1791                                                           funding_redeemscript.clone(), self.channel_value_satoshis,
1792                                                           obscure_factor,
1793                                                           holder_commitment_tx, best_block);
1794
1795                 channel_monitor.provide_latest_counterparty_commitment_tx(counterparty_initial_commitment_txid, Vec::new(), self.cur_counterparty_commitment_transaction_number, self.counterparty_cur_commitment_point.unwrap(), logger);
1796
1797                 self.channel_state = ChannelState::FundingSent as u32;
1798                 self.channel_id = funding_txo.to_channel_id();
1799                 self.cur_counterparty_commitment_transaction_number -= 1;
1800                 self.cur_holder_commitment_transaction_number -= 1;
1801
1802                 log_info!(logger, "Generated funding_signed for peer for channel {}", log_bytes!(self.channel_id()));
1803
1804                 Ok((msgs::FundingSigned {
1805                         channel_id: self.channel_id,
1806                         signature
1807                 }, channel_monitor))
1808         }
1809
1810         /// Handles a funding_signed message from the remote end.
1811         /// If this call is successful, broadcast the funding transaction (and not before!)
1812         pub fn funding_signed<L: Deref>(&mut self, msg: &msgs::FundingSigned, best_block: BestBlock, logger: &L) -> Result<(ChannelMonitor<Signer>, Transaction), ChannelError> where L::Target: Logger {
1813                 if !self.is_outbound() {
1814                         return Err(ChannelError::Close("Received funding_signed for an inbound channel?".to_owned()));
1815                 }
1816                 if self.channel_state & !(ChannelState::MonitorUpdateFailed as u32) != ChannelState::FundingCreated as u32 {
1817                         return Err(ChannelError::Close("Received funding_signed in strange state!".to_owned()));
1818                 }
1819                 if self.commitment_secrets.get_min_seen_secret() != (1 << 48) ||
1820                                 self.cur_counterparty_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER ||
1821                                 self.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
1822                         panic!("Should not have advanced channel commitment tx numbers prior to funding_created");
1823                 }
1824
1825                 let funding_script = self.get_funding_redeemscript();
1826
1827                 let counterparty_keys = self.build_remote_transaction_keys()?;
1828                 let counterparty_initial_commitment_tx = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, false, logger).0;
1829                 let counterparty_trusted_tx = counterparty_initial_commitment_tx.trust();
1830                 let counterparty_initial_bitcoin_tx = counterparty_trusted_tx.built_transaction();
1831
1832                 log_trace!(logger, "Initial counterparty tx for channel {} is: txid {} tx {}",
1833                         log_bytes!(self.channel_id()), counterparty_initial_bitcoin_tx.txid, encode::serialize_hex(&counterparty_initial_bitcoin_tx.transaction));
1834
1835                 let holder_signer = self.build_holder_transaction_keys(self.cur_holder_commitment_transaction_number)?;
1836                 let initial_commitment_tx = self.build_commitment_transaction(self.cur_holder_commitment_transaction_number, &holder_signer, true, false, logger).0;
1837                 {
1838                         let trusted_tx = initial_commitment_tx.trust();
1839                         let initial_commitment_bitcoin_tx = trusted_tx.built_transaction();
1840                         let sighash = initial_commitment_bitcoin_tx.get_sighash_all(&funding_script, self.channel_value_satoshis);
1841                         // They sign our commitment transaction, allowing us to broadcast the tx if we wish.
1842                         if let Err(_) = self.secp_ctx.verify(&sighash, &msg.signature, &self.get_counterparty_pubkeys().funding_pubkey) {
1843                                 return Err(ChannelError::Close("Invalid funding_signed signature from peer".to_owned()));
1844                         }
1845                 }
1846
1847                 let holder_commitment_tx = HolderCommitmentTransaction::new(
1848                         initial_commitment_tx,
1849                         msg.signature,
1850                         Vec::new(),
1851                         &self.get_holder_pubkeys().funding_pubkey,
1852                         self.counterparty_funding_pubkey()
1853                 );
1854
1855
1856                 let funding_redeemscript = self.get_funding_redeemscript();
1857                 let funding_txo = self.get_funding_txo().unwrap();
1858                 let funding_txo_script = funding_redeemscript.to_v0_p2wsh();
1859                 let obscure_factor = get_commitment_transaction_number_obscure_factor(&self.get_holder_pubkeys().payment_point, &self.get_counterparty_pubkeys().payment_point, self.is_outbound());
1860                 let shutdown_script = self.shutdown_scriptpubkey.clone().map(|script| script.into_inner());
1861                 let channel_monitor = ChannelMonitor::new(self.secp_ctx.clone(), self.holder_signer.clone(),
1862                                                           shutdown_script, self.get_holder_selected_contest_delay(),
1863                                                           &self.destination_script, (funding_txo, funding_txo_script),
1864                                                           &self.channel_transaction_parameters,
1865                                                           funding_redeemscript.clone(), self.channel_value_satoshis,
1866                                                           obscure_factor,
1867                                                           holder_commitment_tx, best_block);
1868
1869                 channel_monitor.provide_latest_counterparty_commitment_tx(counterparty_initial_bitcoin_tx.txid, Vec::new(), self.cur_counterparty_commitment_transaction_number, self.counterparty_cur_commitment_point.unwrap(), logger);
1870
1871                 assert_eq!(self.channel_state & (ChannelState::MonitorUpdateFailed as u32), 0); // We have no had any monitor(s) yet to fail update!
1872                 self.channel_state = ChannelState::FundingSent as u32;
1873                 self.cur_holder_commitment_transaction_number -= 1;
1874                 self.cur_counterparty_commitment_transaction_number -= 1;
1875
1876                 log_info!(logger, "Received funding_signed from peer for channel {}", log_bytes!(self.channel_id()));
1877
1878                 Ok((channel_monitor, self.funding_transaction.as_ref().cloned().unwrap()))
1879         }
1880
1881         pub fn funding_locked<L: Deref>(&mut self, msg: &msgs::FundingLocked, logger: &L) -> Result<(), ChannelError> where L::Target: Logger {
1882                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
1883                         self.workaround_lnd_bug_4006 = Some(msg.clone());
1884                         return Err(ChannelError::Ignore("Peer sent funding_locked when we needed a channel_reestablish. The peer is likely lnd, see https://github.com/lightningnetwork/lnd/issues/4006".to_owned()));
1885                 }
1886
1887                 let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
1888
1889                 if non_shutdown_state == ChannelState::FundingSent as u32 {
1890                         self.channel_state |= ChannelState::TheirFundingLocked as u32;
1891                 } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::OurFundingLocked as u32) {
1892                         self.channel_state = ChannelState::ChannelFunded as u32 | (self.channel_state & MULTI_STATE_FLAGS);
1893                         self.update_time_counter += 1;
1894                 } else if (self.channel_state & (ChannelState::ChannelFunded as u32) != 0 &&
1895                                  // Note that funding_signed/funding_created will have decremented both by 1!
1896                                  self.cur_holder_commitment_transaction_number == INITIAL_COMMITMENT_NUMBER - 1 &&
1897                                  self.cur_counterparty_commitment_transaction_number == INITIAL_COMMITMENT_NUMBER - 1) ||
1898                                 // If we reconnected before sending our funding locked they may still resend theirs:
1899                                 (self.channel_state & (ChannelState::FundingSent as u32 | ChannelState::TheirFundingLocked as u32) ==
1900                                                       (ChannelState::FundingSent as u32 | ChannelState::TheirFundingLocked as u32)) {
1901                         if self.counterparty_cur_commitment_point != Some(msg.next_per_commitment_point) {
1902                                 return Err(ChannelError::Close("Peer sent a reconnect funding_locked with a different point".to_owned()));
1903                         }
1904                         // They probably disconnected/reconnected and re-sent the funding_locked, which is required
1905                         return Ok(());
1906                 } else {
1907                         return Err(ChannelError::Close("Peer sent a funding_locked at a strange time".to_owned()));
1908                 }
1909
1910                 self.counterparty_prev_commitment_point = self.counterparty_cur_commitment_point;
1911                 self.counterparty_cur_commitment_point = Some(msg.next_per_commitment_point);
1912
1913                 log_info!(logger, "Received funding_locked from peer for channel {}", log_bytes!(self.channel_id()));
1914
1915                 Ok(())
1916         }
1917
1918         /// Returns a HTLCStats about inbound pending htlcs
1919         fn get_inbound_pending_htlc_stats(&self) -> HTLCStats {
1920                 let mut stats = HTLCStats {
1921                         pending_htlcs: self.pending_inbound_htlcs.len() as u32,
1922                         pending_htlcs_value_msat: 0,
1923                         on_counterparty_tx_dust_exposure_msat: 0,
1924                         on_holder_tx_dust_exposure_msat: 0,
1925                 };
1926
1927                 let counterparty_dust_limit_timeout_sat = (self.get_dust_buffer_feerate() as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + self.counterparty_dust_limit_satoshis;
1928                 let holder_dust_limit_success_sat = (self.get_dust_buffer_feerate() as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) + self.holder_dust_limit_satoshis;
1929                 for ref htlc in self.pending_inbound_htlcs.iter() {
1930                         stats.pending_htlcs_value_msat += htlc.amount_msat;
1931                         if htlc.amount_msat / 1000 < counterparty_dust_limit_timeout_sat {
1932                                 stats.on_counterparty_tx_dust_exposure_msat += htlc.amount_msat;
1933                         }
1934                         if htlc.amount_msat / 1000 < holder_dust_limit_success_sat {
1935                                 stats.on_holder_tx_dust_exposure_msat += htlc.amount_msat;
1936                         }
1937                 }
1938                 stats
1939         }
1940
1941         /// Returns a HTLCStats about pending outbound htlcs, *including* pending adds in our holding cell.
1942         fn get_outbound_pending_htlc_stats(&self) -> HTLCStats {
1943                 let mut stats = HTLCStats {
1944                         pending_htlcs: self.pending_outbound_htlcs.len() as u32,
1945                         pending_htlcs_value_msat: 0,
1946                         on_counterparty_tx_dust_exposure_msat: 0,
1947                         on_holder_tx_dust_exposure_msat: 0,
1948                 };
1949
1950                 let counterparty_dust_limit_success_sat = (self.get_dust_buffer_feerate() as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) + self.counterparty_dust_limit_satoshis;
1951                 let holder_dust_limit_timeout_sat = (self.get_dust_buffer_feerate() as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + self.holder_dust_limit_satoshis;
1952                 for ref htlc in self.pending_outbound_htlcs.iter() {
1953                         stats.pending_htlcs_value_msat += htlc.amount_msat;
1954                         if htlc.amount_msat / 1000 < counterparty_dust_limit_success_sat {
1955                                 stats.on_counterparty_tx_dust_exposure_msat += htlc.amount_msat;
1956                         }
1957                         if htlc.amount_msat / 1000 < holder_dust_limit_timeout_sat {
1958                                 stats.on_holder_tx_dust_exposure_msat += htlc.amount_msat;
1959                         }
1960                 }
1961
1962                 for update in self.holding_cell_htlc_updates.iter() {
1963                         if let &HTLCUpdateAwaitingACK::AddHTLC { ref amount_msat, .. } = update {
1964                                 stats.pending_htlcs += 1;
1965                                 stats.pending_htlcs_value_msat += amount_msat;
1966                                 if *amount_msat / 1000 < counterparty_dust_limit_success_sat {
1967                                         stats.on_counterparty_tx_dust_exposure_msat += amount_msat;
1968                                 }
1969                                 if *amount_msat / 1000 < holder_dust_limit_timeout_sat {
1970                                         stats.on_holder_tx_dust_exposure_msat += amount_msat;
1971                                 }
1972                         }
1973                 }
1974                 stats
1975         }
1976
1977         /// Get the available (ie not including pending HTLCs) inbound and outbound balance in msat.
1978         /// Doesn't bother handling the
1979         /// if-we-removed-it-already-but-haven't-fully-resolved-they-can-still-send-an-inbound-HTLC
1980         /// corner case properly.
1981         pub fn get_inbound_outbound_available_balance_msat(&self) -> (u64, u64) {
1982                 // Note that we have to handle overflow due to the above case.
1983                 (
1984                         cmp::max(self.channel_value_satoshis as i64 * 1000
1985                                 - self.value_to_self_msat as i64
1986                                 - self.get_inbound_pending_htlc_stats().pending_htlcs_value_msat as i64
1987                                 - Self::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis) as i64 * 1000,
1988                         0) as u64,
1989                         cmp::max(self.value_to_self_msat as i64
1990                                 - self.get_outbound_pending_htlc_stats().pending_htlcs_value_msat as i64
1991                                 - self.counterparty_selected_channel_reserve_satoshis.unwrap_or(0) as i64 * 1000,
1992                         0) as u64
1993                 )
1994         }
1995
1996         pub fn get_holder_counterparty_selected_channel_reserve_satoshis(&self) -> (u64, Option<u64>) {
1997                 (Self::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis),
1998                 self.counterparty_selected_channel_reserve_satoshis)
1999         }
2000
2001         // Get the fee cost of a commitment tx with a given number of HTLC outputs.
2002         // Note that num_htlcs should not include dust HTLCs.
2003         fn commit_tx_fee_msat(&self, num_htlcs: usize) -> u64 {
2004                 // Note that we need to divide before multiplying to round properly,
2005                 // since the lowest denomination of bitcoin on-chain is the satoshi.
2006                 (COMMITMENT_TX_BASE_WEIGHT + num_htlcs as u64 * COMMITMENT_TX_WEIGHT_PER_HTLC) * self.feerate_per_kw as u64 / 1000 * 1000
2007         }
2008
2009         // Get the commitment tx fee for the local's (i.e. our) next commitment transaction based on the
2010         // number of pending HTLCs that are on track to be in our next commitment tx, plus an additional
2011         // HTLC if `fee_spike_buffer_htlc` is Some, plus a new HTLC given by `new_htlc_amount`. Dust HTLCs
2012         // are excluded.
2013         fn next_local_commit_tx_fee_msat(&self, htlc: HTLCCandidate, fee_spike_buffer_htlc: Option<()>) -> u64 {
2014                 assert!(self.is_outbound());
2015
2016                 let real_dust_limit_success_sat = (self.feerate_per_kw as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) + self.holder_dust_limit_satoshis;
2017                 let real_dust_limit_timeout_sat = (self.feerate_per_kw as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + self.holder_dust_limit_satoshis;
2018
2019                 let mut addl_htlcs = 0;
2020                 if fee_spike_buffer_htlc.is_some() { addl_htlcs += 1; }
2021                 match htlc.origin {
2022                         HTLCInitiator::LocalOffered => {
2023                                 if htlc.amount_msat / 1000 >= real_dust_limit_timeout_sat {
2024                                         addl_htlcs += 1;
2025                                 }
2026                         },
2027                         HTLCInitiator::RemoteOffered => {
2028                                 if htlc.amount_msat / 1000 >= real_dust_limit_success_sat {
2029                                         addl_htlcs += 1;
2030                                 }
2031                         }
2032                 }
2033
2034                 let mut included_htlcs = 0;
2035                 for ref htlc in self.pending_inbound_htlcs.iter() {
2036                         if htlc.amount_msat / 1000 < real_dust_limit_success_sat {
2037                                 continue
2038                         }
2039                         // We include LocalRemoved HTLCs here because we may still need to broadcast a commitment
2040                         // transaction including this HTLC if it times out before they RAA.
2041                         included_htlcs += 1;
2042                 }
2043
2044                 for ref htlc in self.pending_outbound_htlcs.iter() {
2045                         if htlc.amount_msat / 1000 < real_dust_limit_timeout_sat {
2046                                 continue
2047                         }
2048                         match htlc.state {
2049                                 OutboundHTLCState::LocalAnnounced {..} => included_htlcs += 1,
2050                                 OutboundHTLCState::Committed => included_htlcs += 1,
2051                                 OutboundHTLCState::RemoteRemoved {..} => included_htlcs += 1,
2052                                 // We don't include AwaitingRemoteRevokeToRemove HTLCs because our next commitment
2053                                 // transaction won't be generated until they send us their next RAA, which will mean
2054                                 // dropping any HTLCs in this state.
2055                                 _ => {},
2056                         }
2057                 }
2058
2059                 for htlc in self.holding_cell_htlc_updates.iter() {
2060                         match htlc {
2061                                 &HTLCUpdateAwaitingACK::AddHTLC { amount_msat, .. } => {
2062                                         if amount_msat / 1000 < real_dust_limit_timeout_sat {
2063                                                 continue
2064                                         }
2065                                         included_htlcs += 1
2066                                 },
2067                                 _ => {}, // Don't include claims/fails that are awaiting ack, because once we get the
2068                                          // ack we're guaranteed to never include them in commitment txs anymore.
2069                         }
2070                 }
2071
2072                 let num_htlcs = included_htlcs + addl_htlcs;
2073                 let res = self.commit_tx_fee_msat(num_htlcs);
2074                 #[cfg(any(test, feature = "fuzztarget"))]
2075                 {
2076                         let mut fee = res;
2077                         if fee_spike_buffer_htlc.is_some() {
2078                                 fee = self.commit_tx_fee_msat(num_htlcs - 1);
2079                         }
2080                         let total_pending_htlcs = self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len()
2081                                 + self.holding_cell_htlc_updates.len();
2082                         let commitment_tx_info = CommitmentTxInfoCached {
2083                                 fee,
2084                                 total_pending_htlcs,
2085                                 next_holder_htlc_id: match htlc.origin {
2086                                         HTLCInitiator::LocalOffered => self.next_holder_htlc_id + 1,
2087                                         HTLCInitiator::RemoteOffered => self.next_holder_htlc_id,
2088                                 },
2089                                 next_counterparty_htlc_id: match htlc.origin {
2090                                         HTLCInitiator::LocalOffered => self.next_counterparty_htlc_id,
2091                                         HTLCInitiator::RemoteOffered => self.next_counterparty_htlc_id + 1,
2092                                 },
2093                                 feerate: self.feerate_per_kw,
2094                         };
2095                         *self.next_local_commitment_tx_fee_info_cached.lock().unwrap() = Some(commitment_tx_info);
2096                 }
2097                 res
2098         }
2099
2100         // Get the commitment tx fee for the remote's next commitment transaction based on the number of
2101         // pending HTLCs that are on track to be in their next commitment tx, plus an additional HTLC if
2102         // `fee_spike_buffer_htlc` is Some, plus a new HTLC given by `new_htlc_amount`. Dust HTLCs are
2103         // excluded.
2104         fn next_remote_commit_tx_fee_msat(&self, htlc: HTLCCandidate, fee_spike_buffer_htlc: Option<()>) -> u64 {
2105                 assert!(!self.is_outbound());
2106
2107                 let real_dust_limit_success_sat = (self.feerate_per_kw as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) + self.counterparty_dust_limit_satoshis;
2108                 let real_dust_limit_timeout_sat = (self.feerate_per_kw as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + self.counterparty_dust_limit_satoshis;
2109
2110                 let mut addl_htlcs = 0;
2111                 if fee_spike_buffer_htlc.is_some() { addl_htlcs += 1; }
2112                 match htlc.origin {
2113                         HTLCInitiator::LocalOffered => {
2114                                 if htlc.amount_msat / 1000 >= real_dust_limit_success_sat {
2115                                         addl_htlcs += 1;
2116                                 }
2117                         },
2118                         HTLCInitiator::RemoteOffered => {
2119                                 if htlc.amount_msat / 1000 >= real_dust_limit_timeout_sat {
2120                                         addl_htlcs += 1;
2121                                 }
2122                         }
2123                 }
2124
2125                 // When calculating the set of HTLCs which will be included in their next commitment_signed, all
2126                 // non-dust inbound HTLCs are included (as all states imply it will be included) and only
2127                 // committed outbound HTLCs, see below.
2128                 let mut included_htlcs = 0;
2129                 for ref htlc in self.pending_inbound_htlcs.iter() {
2130                         if htlc.amount_msat / 1000 <= real_dust_limit_timeout_sat {
2131                                 continue
2132                         }
2133                         included_htlcs += 1;
2134                 }
2135
2136                 for ref htlc in self.pending_outbound_htlcs.iter() {
2137                         if htlc.amount_msat / 1000 <= real_dust_limit_success_sat {
2138                                 continue
2139                         }
2140                         // We only include outbound HTLCs if it will not be included in their next commitment_signed,
2141                         // i.e. if they've responded to us with an RAA after announcement.
2142                         match htlc.state {
2143                                 OutboundHTLCState::Committed => included_htlcs += 1,
2144                                 OutboundHTLCState::RemoteRemoved {..} => included_htlcs += 1,
2145                                 OutboundHTLCState::LocalAnnounced { .. } => included_htlcs += 1,
2146                                 _ => {},
2147                         }
2148                 }
2149
2150                 let num_htlcs = included_htlcs + addl_htlcs;
2151                 let res = self.commit_tx_fee_msat(num_htlcs);
2152                 #[cfg(any(test, feature = "fuzztarget"))]
2153                 {
2154                         let mut fee = res;
2155                         if fee_spike_buffer_htlc.is_some() {
2156                                 fee = self.commit_tx_fee_msat(num_htlcs - 1);
2157                         }
2158                         let total_pending_htlcs = self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len();
2159                         let commitment_tx_info = CommitmentTxInfoCached {
2160                                 fee,
2161                                 total_pending_htlcs,
2162                                 next_holder_htlc_id: match htlc.origin {
2163                                         HTLCInitiator::LocalOffered => self.next_holder_htlc_id + 1,
2164                                         HTLCInitiator::RemoteOffered => self.next_holder_htlc_id,
2165                                 },
2166                                 next_counterparty_htlc_id: match htlc.origin {
2167                                         HTLCInitiator::LocalOffered => self.next_counterparty_htlc_id,
2168                                         HTLCInitiator::RemoteOffered => self.next_counterparty_htlc_id + 1,
2169                                 },
2170                                 feerate: self.feerate_per_kw,
2171                         };
2172                         *self.next_remote_commitment_tx_fee_info_cached.lock().unwrap() = Some(commitment_tx_info);
2173                 }
2174                 res
2175         }
2176
2177         pub fn update_add_htlc<F, L: Deref>(&mut self, msg: &msgs::UpdateAddHTLC, mut pending_forward_status: PendingHTLCStatus, create_pending_htlc_status: F, logger: &L) -> Result<(), ChannelError>
2178         where F: for<'a> Fn(&'a Self, PendingHTLCStatus, u16) -> PendingHTLCStatus, L::Target: Logger {
2179                 // We can't accept HTLCs sent after we've sent a shutdown.
2180                 let local_sent_shutdown = (self.channel_state & (ChannelState::ChannelFunded as u32 | ChannelState::LocalShutdownSent as u32)) != (ChannelState::ChannelFunded as u32);
2181                 if local_sent_shutdown {
2182                         pending_forward_status = create_pending_htlc_status(self, pending_forward_status, 0x1000|20);
2183                 }
2184                 // If the remote has sent a shutdown prior to adding this HTLC, then they are in violation of the spec.
2185                 let remote_sent_shutdown = (self.channel_state & (ChannelState::ChannelFunded as u32 | ChannelState::RemoteShutdownSent as u32)) != (ChannelState::ChannelFunded as u32);
2186                 if remote_sent_shutdown {
2187                         return Err(ChannelError::Close("Got add HTLC message when channel was not in an operational state".to_owned()));
2188                 }
2189                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2190                         return Err(ChannelError::Close("Peer sent update_add_htlc when we needed a channel_reestablish".to_owned()));
2191                 }
2192                 if msg.amount_msat > self.channel_value_satoshis * 1000 {
2193                         return Err(ChannelError::Close("Remote side tried to send more than the total value of the channel".to_owned()));
2194                 }
2195                 if msg.amount_msat == 0 {
2196                         return Err(ChannelError::Close("Remote side tried to send a 0-msat HTLC".to_owned()));
2197                 }
2198                 if msg.amount_msat < self.holder_htlc_minimum_msat {
2199                         return Err(ChannelError::Close(format!("Remote side tried to send less than our minimum HTLC value. Lower limit: ({}). Actual: ({})", self.holder_htlc_minimum_msat, msg.amount_msat)));
2200                 }
2201
2202                 let inbound_stats = self.get_inbound_pending_htlc_stats();
2203                 let outbound_stats = self.get_outbound_pending_htlc_stats();
2204                 if inbound_stats.pending_htlcs + 1 > OUR_MAX_HTLCS as u32 {
2205                         return Err(ChannelError::Close(format!("Remote tried to push more than our max accepted HTLCs ({})", OUR_MAX_HTLCS)));
2206                 }
2207                 let holder_max_htlc_value_in_flight_msat = Channel::<Signer>::get_holder_max_htlc_value_in_flight_msat(self.channel_value_satoshis);
2208                 if inbound_stats.pending_htlcs_value_msat + msg.amount_msat > holder_max_htlc_value_in_flight_msat {
2209                         return Err(ChannelError::Close(format!("Remote HTLC add would put them over our max HTLC value ({})", holder_max_htlc_value_in_flight_msat)));
2210                 }
2211                 // Check holder_selected_channel_reserve_satoshis (we're getting paid, so they have to at least meet
2212                 // the reserve_satoshis we told them to always have as direct payment so that they lose
2213                 // something if we punish them for broadcasting an old state).
2214                 // Note that we don't really care about having a small/no to_remote output in our local
2215                 // commitment transactions, as the purpose of the channel reserve is to ensure we can
2216                 // punish *them* if they misbehave, so we discount any outbound HTLCs which will not be
2217                 // present in the next commitment transaction we send them (at least for fulfilled ones,
2218                 // failed ones won't modify value_to_self).
2219                 // Note that we will send HTLCs which another instance of rust-lightning would think
2220                 // violate the reserve value if we do not do this (as we forget inbound HTLCs from the
2221                 // Channel state once they will not be present in the next received commitment
2222                 // transaction).
2223                 let mut removed_outbound_total_msat = 0;
2224                 for ref htlc in self.pending_outbound_htlcs.iter() {
2225                         if let OutboundHTLCState::AwaitingRemoteRevokeToRemove(None) = htlc.state {
2226                                 removed_outbound_total_msat += htlc.amount_msat;
2227                         } else if let OutboundHTLCState::AwaitingRemovedRemoteRevoke(None) = htlc.state {
2228                                 removed_outbound_total_msat += htlc.amount_msat;
2229                         }
2230                 }
2231
2232                 let exposure_dust_limit_timeout_sats = (self.get_dust_buffer_feerate() as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + self.counterparty_dust_limit_satoshis;
2233                 if msg.amount_msat / 1000 < exposure_dust_limit_timeout_sats {
2234                         let on_counterparty_tx_dust_htlc_exposure_msat = inbound_stats.on_counterparty_tx_dust_exposure_msat + outbound_stats.on_counterparty_tx_dust_exposure_msat + msg.amount_msat;
2235                         if on_counterparty_tx_dust_htlc_exposure_msat > self.get_max_dust_htlc_exposure_msat() {
2236                                 log_info!(logger, "Cannot accept value that would put our exposure to dust HTLCs at {} over the limit {} on counterparty commitment tx",
2237                                         on_counterparty_tx_dust_htlc_exposure_msat, self.get_max_dust_htlc_exposure_msat());
2238                                 pending_forward_status = create_pending_htlc_status(self, pending_forward_status, 0x1000|7);
2239                         }
2240                 }
2241
2242                 let exposure_dust_limit_success_sats = (self.get_dust_buffer_feerate() as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) + self.holder_dust_limit_satoshis;
2243                 if msg.amount_msat / 1000 < exposure_dust_limit_success_sats {
2244                         let on_holder_tx_dust_htlc_exposure_msat = inbound_stats.on_holder_tx_dust_exposure_msat + outbound_stats.on_holder_tx_dust_exposure_msat + msg.amount_msat;
2245                         if on_holder_tx_dust_htlc_exposure_msat > self.get_max_dust_htlc_exposure_msat() {
2246                                 log_info!(logger, "Cannot accept value that would put our exposure to dust HTLCs at {} over the limit {} on holder commitment tx",
2247                                         on_holder_tx_dust_htlc_exposure_msat, self.get_max_dust_htlc_exposure_msat());
2248                                 pending_forward_status = create_pending_htlc_status(self, pending_forward_status, 0x1000|7);
2249                         }
2250                 }
2251
2252                 let pending_value_to_self_msat =
2253                         self.value_to_self_msat + inbound_stats.pending_htlcs_value_msat - removed_outbound_total_msat;
2254                 let pending_remote_value_msat =
2255                         self.channel_value_satoshis * 1000 - pending_value_to_self_msat;
2256                 if pending_remote_value_msat < msg.amount_msat {
2257                         return Err(ChannelError::Close("Remote HTLC add would overdraw remaining funds".to_owned()));
2258                 }
2259
2260                 // Check that the remote can afford to pay for this HTLC on-chain at the current
2261                 // feerate_per_kw, while maintaining their channel reserve (as required by the spec).
2262                 let remote_commit_tx_fee_msat = if self.is_outbound() { 0 } else {
2263                         let htlc_candidate = HTLCCandidate::new(msg.amount_msat, HTLCInitiator::RemoteOffered);
2264                         self.next_remote_commit_tx_fee_msat(htlc_candidate, None) // Don't include the extra fee spike buffer HTLC in calculations
2265                 };
2266                 if pending_remote_value_msat - msg.amount_msat < remote_commit_tx_fee_msat {
2267                         return Err(ChannelError::Close("Remote HTLC add would not leave enough to pay for fees".to_owned()));
2268                 };
2269
2270                 let chan_reserve_msat =
2271                         Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis) * 1000;
2272                 if pending_remote_value_msat - msg.amount_msat - remote_commit_tx_fee_msat < chan_reserve_msat {
2273                         return Err(ChannelError::Close("Remote HTLC add would put them under remote reserve value".to_owned()));
2274                 }
2275
2276                 if !self.is_outbound() {
2277                         // `2 *` and `Some(())` is for the fee spike buffer we keep for the remote. This deviates from
2278                         // the spec because in the spec, the fee spike buffer requirement doesn't exist on the
2279                         // receiver's side, only on the sender's.
2280                         // Note that when we eventually remove support for fee updates and switch to anchor output
2281                         // fees, we will drop the `2 *`, since we no longer be as sensitive to fee spikes. But, keep
2282                         // the extra htlc when calculating the next remote commitment transaction fee as we should
2283                         // still be able to afford adding this HTLC plus one more future HTLC, regardless of being
2284                         // sensitive to fee spikes.
2285                         let htlc_candidate = HTLCCandidate::new(msg.amount_msat, HTLCInitiator::RemoteOffered);
2286                         let remote_fee_cost_incl_stuck_buffer_msat = 2 * self.next_remote_commit_tx_fee_msat(htlc_candidate, Some(()));
2287                         if pending_remote_value_msat - msg.amount_msat - chan_reserve_msat < remote_fee_cost_incl_stuck_buffer_msat {
2288                                 // Note that if the pending_forward_status is not updated here, then it's because we're already failing
2289                                 // the HTLC, i.e. its status is already set to failing.
2290                                 log_info!(logger, "Attempting to fail HTLC due to fee spike buffer violation in channel {}. Rebalancing is required.", log_bytes!(self.channel_id()));
2291                                 pending_forward_status = create_pending_htlc_status(self, pending_forward_status, 0x1000|7);
2292                         }
2293                 } else {
2294                         // Check that they won't violate our local required channel reserve by adding this HTLC.
2295                         let htlc_candidate = HTLCCandidate::new(msg.amount_msat, HTLCInitiator::RemoteOffered);
2296                         let local_commit_tx_fee_msat = self.next_local_commit_tx_fee_msat(htlc_candidate, None);
2297                         if self.value_to_self_msat < self.counterparty_selected_channel_reserve_satoshis.unwrap() * 1000 + local_commit_tx_fee_msat {
2298                                 return Err(ChannelError::Close("Cannot accept HTLC that would put our balance under counterparty-announced channel reserve value".to_owned()));
2299                         }
2300                 }
2301                 if self.next_counterparty_htlc_id != msg.htlc_id {
2302                         return Err(ChannelError::Close(format!("Remote skipped HTLC ID (skipped ID: {})", self.next_counterparty_htlc_id)));
2303                 }
2304                 if msg.cltv_expiry >= 500000000 {
2305                         return Err(ChannelError::Close("Remote provided CLTV expiry in seconds instead of block height".to_owned()));
2306                 }
2307
2308                 if self.channel_state & ChannelState::LocalShutdownSent as u32 != 0 {
2309                         if let PendingHTLCStatus::Forward(_) = pending_forward_status {
2310                                 panic!("ChannelManager shouldn't be trying to add a forwardable HTLC after we've started closing");
2311                         }
2312                 }
2313
2314                 // Now update local state:
2315                 self.next_counterparty_htlc_id += 1;
2316                 self.pending_inbound_htlcs.push(InboundHTLCOutput {
2317                         htlc_id: msg.htlc_id,
2318                         amount_msat: msg.amount_msat,
2319                         payment_hash: msg.payment_hash,
2320                         cltv_expiry: msg.cltv_expiry,
2321                         state: InboundHTLCState::RemoteAnnounced(pending_forward_status),
2322                 });
2323                 Ok(())
2324         }
2325
2326         /// Marks an outbound HTLC which we have received update_fail/fulfill/malformed
2327         #[inline]
2328         fn mark_outbound_htlc_removed(&mut self, htlc_id: u64, check_preimage: Option<PaymentHash>, fail_reason: Option<HTLCFailReason>) -> Result<&OutboundHTLCOutput, ChannelError> {
2329                 for htlc in self.pending_outbound_htlcs.iter_mut() {
2330                         if htlc.htlc_id == htlc_id {
2331                                 match check_preimage {
2332                                         None => {},
2333                                         Some(payment_hash) =>
2334                                                 if payment_hash != htlc.payment_hash {
2335                                                         return Err(ChannelError::Close(format!("Remote tried to fulfill HTLC ({}) with an incorrect preimage", htlc_id)));
2336                                                 }
2337                                 };
2338                                 match htlc.state {
2339                                         OutboundHTLCState::LocalAnnounced(_) =>
2340                                                 return Err(ChannelError::Close(format!("Remote tried to fulfill/fail HTLC ({}) before it had been committed", htlc_id))),
2341                                         OutboundHTLCState::Committed => {
2342                                                 htlc.state = OutboundHTLCState::RemoteRemoved(fail_reason);
2343                                         },
2344                                         OutboundHTLCState::AwaitingRemoteRevokeToRemove(_) | OutboundHTLCState::AwaitingRemovedRemoteRevoke(_) | OutboundHTLCState::RemoteRemoved(_) =>
2345                                                 return Err(ChannelError::Close(format!("Remote tried to fulfill/fail HTLC ({}) that they'd already fulfilled/failed", htlc_id))),
2346                                 }
2347                                 return Ok(htlc);
2348                         }
2349                 }
2350                 Err(ChannelError::Close("Remote tried to fulfill/fail an HTLC we couldn't find".to_owned()))
2351         }
2352
2353         pub fn update_fulfill_htlc(&mut self, msg: &msgs::UpdateFulfillHTLC) -> Result<(HTLCSource, u64), ChannelError> {
2354                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
2355                         return Err(ChannelError::Close("Got fulfill HTLC message when channel was not in an operational state".to_owned()));
2356                 }
2357                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2358                         return Err(ChannelError::Close("Peer sent update_fulfill_htlc when we needed a channel_reestablish".to_owned()));
2359                 }
2360
2361                 let payment_hash = PaymentHash(Sha256::hash(&msg.payment_preimage.0[..]).into_inner());
2362                 self.mark_outbound_htlc_removed(msg.htlc_id, Some(payment_hash), None).map(|htlc| (htlc.source.clone(), htlc.amount_msat))
2363         }
2364
2365         pub fn update_fail_htlc(&mut self, msg: &msgs::UpdateFailHTLC, fail_reason: HTLCFailReason) -> Result<(), ChannelError> {
2366                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
2367                         return Err(ChannelError::Close("Got fail HTLC message when channel was not in an operational state".to_owned()));
2368                 }
2369                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2370                         return Err(ChannelError::Close("Peer sent update_fail_htlc when we needed a channel_reestablish".to_owned()));
2371                 }
2372
2373                 self.mark_outbound_htlc_removed(msg.htlc_id, None, Some(fail_reason))?;
2374                 Ok(())
2375         }
2376
2377         pub fn update_fail_malformed_htlc(&mut self, msg: &msgs::UpdateFailMalformedHTLC, fail_reason: HTLCFailReason) -> Result<(), ChannelError> {
2378                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
2379                         return Err(ChannelError::Close("Got fail malformed HTLC message when channel was not in an operational state".to_owned()));
2380                 }
2381                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2382                         return Err(ChannelError::Close("Peer sent update_fail_malformed_htlc when we needed a channel_reestablish".to_owned()));
2383                 }
2384
2385                 self.mark_outbound_htlc_removed(msg.htlc_id, None, Some(fail_reason))?;
2386                 Ok(())
2387         }
2388
2389         pub fn commitment_signed<L: Deref>(&mut self, msg: &msgs::CommitmentSigned, logger: &L) -> Result<(msgs::RevokeAndACK, Option<msgs::CommitmentSigned>, ChannelMonitorUpdate), (Option<ChannelMonitorUpdate>, ChannelError)>
2390                 where L::Target: Logger
2391         {
2392                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
2393                         return Err((None, ChannelError::Close("Got commitment signed message when channel was not in an operational state".to_owned())));
2394                 }
2395                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2396                         return Err((None, ChannelError::Close("Peer sent commitment_signed when we needed a channel_reestablish".to_owned())));
2397                 }
2398                 if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK == BOTH_SIDES_SHUTDOWN_MASK && self.last_sent_closing_fee.is_some() {
2399                         return Err((None, ChannelError::Close("Peer sent commitment_signed after we'd started exchanging closing_signeds".to_owned())));
2400                 }
2401
2402                 let funding_script = self.get_funding_redeemscript();
2403
2404                 let keys = self.build_holder_transaction_keys(self.cur_holder_commitment_transaction_number).map_err(|e| (None, e))?;
2405
2406                 let (num_htlcs, mut htlcs_cloned, commitment_tx, commitment_txid, feerate_per_kw) = {
2407                         let commitment_tx = self.build_commitment_transaction(self.cur_holder_commitment_transaction_number, &keys, true, false, logger);
2408                         let commitment_txid = {
2409                                 let trusted_tx = commitment_tx.0.trust();
2410                                 let bitcoin_tx = trusted_tx.built_transaction();
2411                                 let sighash = bitcoin_tx.get_sighash_all(&funding_script, self.channel_value_satoshis);
2412
2413                                 log_trace!(logger, "Checking commitment tx signature {} by key {} against tx {} (sighash {}) with redeemscript {} in channel {}",
2414                                         log_bytes!(msg.signature.serialize_compact()[..]),
2415                                         log_bytes!(self.counterparty_funding_pubkey().serialize()), encode::serialize_hex(&bitcoin_tx.transaction),
2416                                         log_bytes!(sighash[..]), encode::serialize_hex(&funding_script), log_bytes!(self.channel_id()));
2417                                 if let Err(_) = self.secp_ctx.verify(&sighash, &msg.signature, &self.counterparty_funding_pubkey()) {
2418                                         return Err((None, ChannelError::Close("Invalid commitment tx signature from peer".to_owned())));
2419                                 }
2420                                 bitcoin_tx.txid
2421                         };
2422                         let htlcs_cloned: Vec<_> = commitment_tx.3.iter().map(|htlc| (htlc.0.clone(), htlc.1.map(|h| h.clone()))).collect();
2423                         (commitment_tx.2, htlcs_cloned, commitment_tx.0, commitment_txid, commitment_tx.1)
2424                 };
2425
2426                 // If our counterparty updated the channel fee in this commitment transaction, check that
2427                 // they can actually afford the new fee now.
2428                 let update_fee = if let Some((_, update_state)) = self.pending_update_fee {
2429                         update_state == FeeUpdateState::RemoteAnnounced
2430                 } else { false };
2431                 if update_fee { debug_assert!(!self.is_outbound()); }
2432                 let total_fee = feerate_per_kw as u64 * (COMMITMENT_TX_BASE_WEIGHT + (num_htlcs as u64) * COMMITMENT_TX_WEIGHT_PER_HTLC) / 1000;
2433                 if update_fee {
2434                         let counterparty_reserve_we_require = Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis);
2435                         if self.channel_value_satoshis - self.value_to_self_msat / 1000 < total_fee + counterparty_reserve_we_require {
2436                                 return Err((None, ChannelError::Close("Funding remote cannot afford proposed new fee".to_owned())));
2437                         }
2438                 }
2439                 #[cfg(any(test, feature = "fuzztarget"))]
2440                 {
2441                         if self.is_outbound() {
2442                                 let projected_commit_tx_info = self.next_local_commitment_tx_fee_info_cached.lock().unwrap().take();
2443                                 *self.next_remote_commitment_tx_fee_info_cached.lock().unwrap() = None;
2444                                 if let Some(info) = projected_commit_tx_info {
2445                                         let total_pending_htlcs = self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len()
2446                                                 + self.holding_cell_htlc_updates.len();
2447                                         if info.total_pending_htlcs == total_pending_htlcs
2448                                                 && info.next_holder_htlc_id == self.next_holder_htlc_id
2449                                                 && info.next_counterparty_htlc_id == self.next_counterparty_htlc_id
2450                                                 && info.feerate == self.feerate_per_kw {
2451                                                         assert_eq!(total_fee, info.fee / 1000);
2452                                                 }
2453                                 }
2454                         }
2455                 }
2456
2457                 if msg.htlc_signatures.len() != num_htlcs {
2458                         return Err((None, ChannelError::Close(format!("Got wrong number of HTLC signatures ({}) from remote. It must be {}", msg.htlc_signatures.len(), num_htlcs))));
2459                 }
2460
2461                 // TODO: Sadly, we pass HTLCs twice to ChannelMonitor: once via the HolderCommitmentTransaction and once via the update
2462                 let mut htlcs_and_sigs = Vec::with_capacity(htlcs_cloned.len());
2463                 for (idx, (htlc, source)) in htlcs_cloned.drain(..).enumerate() {
2464                         if let Some(_) = htlc.transaction_output_index {
2465                                 let htlc_tx = chan_utils::build_htlc_transaction(&commitment_txid, feerate_per_kw,
2466                                         self.get_counterparty_selected_contest_delay().unwrap(), &htlc,
2467                                         &keys.broadcaster_delayed_payment_key, &keys.revocation_key);
2468
2469                                 let htlc_redeemscript = chan_utils::get_htlc_redeemscript(&htlc, &keys);
2470                                 let htlc_sighash = hash_to_message!(&bip143::SigHashCache::new(&htlc_tx).signature_hash(0, &htlc_redeemscript, htlc.amount_msat / 1000, SigHashType::All)[..]);
2471                                 log_trace!(logger, "Checking HTLC tx signature {} by key {} against tx {} (sighash {}) with redeemscript {} in channel {}.",
2472                                         log_bytes!(msg.htlc_signatures[idx].serialize_compact()[..]), log_bytes!(keys.countersignatory_htlc_key.serialize()),
2473                                         encode::serialize_hex(&htlc_tx), log_bytes!(htlc_sighash[..]), encode::serialize_hex(&htlc_redeemscript), log_bytes!(self.channel_id()));
2474                                 if let Err(_) = self.secp_ctx.verify(&htlc_sighash, &msg.htlc_signatures[idx], &keys.countersignatory_htlc_key) {
2475                                         return Err((None, ChannelError::Close("Invalid HTLC tx signature from peer".to_owned())));
2476                                 }
2477                                 htlcs_and_sigs.push((htlc, Some(msg.htlc_signatures[idx]), source));
2478                         } else {
2479                                 htlcs_and_sigs.push((htlc, None, source));
2480                         }
2481                 }
2482
2483                 let holder_commitment_tx = HolderCommitmentTransaction::new(
2484                         commitment_tx,
2485                         msg.signature,
2486                         msg.htlc_signatures.clone(),
2487                         &self.get_holder_pubkeys().funding_pubkey,
2488                         self.counterparty_funding_pubkey()
2489                 );
2490
2491                 let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number - 1, &self.secp_ctx);
2492                 let per_commitment_secret = self.holder_signer.release_commitment_secret(self.cur_holder_commitment_transaction_number + 1);
2493
2494                 // Update state now that we've passed all the can-fail calls...
2495                 let mut need_commitment = false;
2496                 if let &mut Some((_, ref mut update_state)) = &mut self.pending_update_fee {
2497                         if *update_state == FeeUpdateState::RemoteAnnounced {
2498                                 *update_state = FeeUpdateState::AwaitingRemoteRevokeToAnnounce;
2499                                 need_commitment = true;
2500                         }
2501                 }
2502
2503                 self.latest_monitor_update_id += 1;
2504                 let mut monitor_update = ChannelMonitorUpdate {
2505                         update_id: self.latest_monitor_update_id,
2506                         updates: vec![ChannelMonitorUpdateStep::LatestHolderCommitmentTXInfo {
2507                                 commitment_tx: holder_commitment_tx,
2508                                 htlc_outputs: htlcs_and_sigs
2509                         }]
2510                 };
2511
2512                 for htlc in self.pending_inbound_htlcs.iter_mut() {
2513                         let new_forward = if let &InboundHTLCState::RemoteAnnounced(ref forward_info) = &htlc.state {
2514                                 Some(forward_info.clone())
2515                         } else { None };
2516                         if let Some(forward_info) = new_forward {
2517                                 log_trace!(logger, "Updating HTLC {} to AwaitingRemoteRevokeToAnnounce due to commitment_signed in channel {}.",
2518                                         log_bytes!(htlc.payment_hash.0), log_bytes!(self.channel_id));
2519                                 htlc.state = InboundHTLCState::AwaitingRemoteRevokeToAnnounce(forward_info);
2520                                 need_commitment = true;
2521                         }
2522                 }
2523                 for htlc in self.pending_outbound_htlcs.iter_mut() {
2524                         if let Some(fail_reason) = if let &mut OutboundHTLCState::RemoteRemoved(ref mut fail_reason) = &mut htlc.state {
2525                                 Some(fail_reason.take())
2526                         } else { None } {
2527                                 log_trace!(logger, "Updating HTLC {} to AwaitingRemoteRevokeToRemove due to commitment_signed in channel {}.",
2528                                         log_bytes!(htlc.payment_hash.0), log_bytes!(self.channel_id));
2529                                 htlc.state = OutboundHTLCState::AwaitingRemoteRevokeToRemove(fail_reason);
2530                                 need_commitment = true;
2531                         }
2532                 }
2533
2534                 self.cur_holder_commitment_transaction_number -= 1;
2535                 // Note that if we need_commitment & !AwaitingRemoteRevoke we'll call
2536                 // send_commitment_no_status_check() next which will reset this to RAAFirst.
2537                 self.resend_order = RAACommitmentOrder::CommitmentFirst;
2538
2539                 if (self.channel_state & ChannelState::MonitorUpdateFailed as u32) != 0 {
2540                         // In case we initially failed monitor updating without requiring a response, we need
2541                         // to make sure the RAA gets sent first.
2542                         self.monitor_pending_revoke_and_ack = true;
2543                         if need_commitment && (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == 0 {
2544                                 // If we were going to send a commitment_signed after the RAA, go ahead and do all
2545                                 // the corresponding HTLC status updates so that get_last_commitment_update
2546                                 // includes the right HTLCs.
2547                                 self.monitor_pending_commitment_signed = true;
2548                                 let (_, mut additional_update) = self.send_commitment_no_status_check(logger).map_err(|e| (None, e))?;
2549                                 // send_commitment_no_status_check may bump latest_monitor_id but we want them to be
2550                                 // strictly increasing by one, so decrement it here.
2551                                 self.latest_monitor_update_id = monitor_update.update_id;
2552                                 monitor_update.updates.append(&mut additional_update.updates);
2553                         }
2554                         log_debug!(logger, "Received valid commitment_signed from peer in channel {}, updated HTLC state but awaiting a monitor update resolution to reply.",
2555                                 log_bytes!(self.channel_id));
2556                         return Err((Some(monitor_update), ChannelError::Ignore("Previous monitor update failure prevented generation of RAA".to_owned())));
2557                 }
2558
2559                 let commitment_signed = if need_commitment && (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == 0 {
2560                         // If we're AwaitingRemoteRevoke we can't send a new commitment here, but that's ok -
2561                         // we'll send one right away when we get the revoke_and_ack when we
2562                         // free_holding_cell_htlcs().
2563                         let (msg, mut additional_update) = self.send_commitment_no_status_check(logger).map_err(|e| (None, e))?;
2564                         // send_commitment_no_status_check may bump latest_monitor_id but we want them to be
2565                         // strictly increasing by one, so decrement it here.
2566                         self.latest_monitor_update_id = monitor_update.update_id;
2567                         monitor_update.updates.append(&mut additional_update.updates);
2568                         Some(msg)
2569                 } else { None };
2570
2571                 log_debug!(logger, "Received valid commitment_signed from peer in channel {}, updating HTLC state and responding with{} a revoke_and_ack.",
2572                         log_bytes!(self.channel_id()), if commitment_signed.is_some() { " our own commitment_signed and" } else { "" });
2573
2574                 Ok((msgs::RevokeAndACK {
2575                         channel_id: self.channel_id,
2576                         per_commitment_secret,
2577                         next_per_commitment_point,
2578                 }, commitment_signed, monitor_update))
2579         }
2580
2581         /// Public version of the below, checking relevant preconditions first.
2582         /// If we're not in a state where freeing the holding cell makes sense, this is a no-op and
2583         /// returns `(None, Vec::new())`.
2584         pub fn maybe_free_holding_cell_htlcs<L: Deref>(&mut self, logger: &L) -> Result<(Option<(msgs::CommitmentUpdate, ChannelMonitorUpdate)>, Vec<(HTLCSource, PaymentHash)>), ChannelError> where L::Target: Logger {
2585                 if self.channel_state >= ChannelState::ChannelFunded as u32 &&
2586                    (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32)) == 0 {
2587                         self.free_holding_cell_htlcs(logger)
2588                 } else { Ok((None, Vec::new())) }
2589         }
2590
2591         /// Used to fulfill holding_cell_htlcs when we get a remote ack (or implicitly get it by them
2592         /// fulfilling or failing the last pending HTLC)
2593         fn free_holding_cell_htlcs<L: Deref>(&mut self, logger: &L) -> Result<(Option<(msgs::CommitmentUpdate, ChannelMonitorUpdate)>, Vec<(HTLCSource, PaymentHash)>), ChannelError> where L::Target: Logger {
2594                 assert_eq!(self.channel_state & ChannelState::MonitorUpdateFailed as u32, 0);
2595                 if self.holding_cell_htlc_updates.len() != 0 || self.holding_cell_update_fee.is_some() {
2596                         log_trace!(logger, "Freeing holding cell with {} HTLC updates{} in channel {}", self.holding_cell_htlc_updates.len(),
2597                                 if self.holding_cell_update_fee.is_some() { " and a fee update" } else { "" }, log_bytes!(self.channel_id()));
2598
2599                         let mut monitor_update = ChannelMonitorUpdate {
2600                                 update_id: self.latest_monitor_update_id + 1, // We don't increment this yet!
2601                                 updates: Vec::new(),
2602                         };
2603
2604                         let mut htlc_updates = Vec::new();
2605                         mem::swap(&mut htlc_updates, &mut self.holding_cell_htlc_updates);
2606                         let mut update_add_htlcs = Vec::with_capacity(htlc_updates.len());
2607                         let mut update_fulfill_htlcs = Vec::with_capacity(htlc_updates.len());
2608                         let mut update_fail_htlcs = Vec::with_capacity(htlc_updates.len());
2609                         let mut htlcs_to_fail = Vec::new();
2610                         for htlc_update in htlc_updates.drain(..) {
2611                                 // Note that this *can* fail, though it should be due to rather-rare conditions on
2612                                 // fee races with adding too many outputs which push our total payments just over
2613                                 // the limit. In case it's less rare than I anticipate, we may want to revisit
2614                                 // handling this case better and maybe fulfilling some of the HTLCs while attempting
2615                                 // to rebalance channels.
2616                                 match &htlc_update {
2617                                         &HTLCUpdateAwaitingACK::AddHTLC {amount_msat, cltv_expiry, ref payment_hash, ref source, ref onion_routing_packet, ..} => {
2618                                                 match self.send_htlc(amount_msat, *payment_hash, cltv_expiry, source.clone(), onion_routing_packet.clone()) {
2619                                                         Ok(update_add_msg_option) => update_add_htlcs.push(update_add_msg_option.unwrap()),
2620                                                         Err(e) => {
2621                                                                 match e {
2622                                                                         ChannelError::Ignore(ref msg) => {
2623                                                                                 log_info!(logger, "Failed to send HTLC with payment_hash {} due to {} in channel {}",
2624                                                                                         log_bytes!(payment_hash.0), msg, log_bytes!(self.channel_id()));
2625                                                                                 // If we fail to send here, then this HTLC should
2626                                                                                 // be failed backwards. Failing to send here
2627                                                                                 // indicates that this HTLC may keep being put back
2628                                                                                 // into the holding cell without ever being
2629                                                                                 // successfully forwarded/failed/fulfilled, causing
2630                                                                                 // our counterparty to eventually close on us.
2631                                                                                 htlcs_to_fail.push((source.clone(), *payment_hash));
2632                                                                         },
2633                                                                         _ => {
2634                                                                                 panic!("Got a non-IgnoreError action trying to send holding cell HTLC");
2635                                                                         },
2636                                                                 }
2637                                                         }
2638                                                 }
2639                                         },
2640                                         &HTLCUpdateAwaitingACK::ClaimHTLC { ref payment_preimage, htlc_id, .. } => {
2641                                                 // If an HTLC claim was previously added to the holding cell (via
2642                                                 // `get_update_fulfill_htlc`, then generating the claim message itself must
2643                                                 // not fail - any in between attempts to claim the HTLC will have resulted
2644                                                 // in it hitting the holding cell again and we cannot change the state of a
2645                                                 // holding cell HTLC from fulfill to anything else.
2646                                                 let (update_fulfill_msg_option, mut additional_monitor_update) =
2647                                                         if let UpdateFulfillFetch::NewClaim { msg, monitor_update, .. } = self.get_update_fulfill_htlc(htlc_id, *payment_preimage, logger) {
2648                                                                 (msg, monitor_update)
2649                                                         } else { unreachable!() };
2650                                                 update_fulfill_htlcs.push(update_fulfill_msg_option.unwrap());
2651                                                 monitor_update.updates.append(&mut additional_monitor_update.updates);
2652                                         },
2653                                         &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, ref err_packet } => {
2654                                                 match self.get_update_fail_htlc(htlc_id, err_packet.clone(), logger) {
2655                                                         Ok(update_fail_msg_option) => {
2656                                                                 // If an HTLC failure was previously added to the holding cell (via
2657                                                                 // `get_update_fail_htlc`) then generating the fail message itself
2658                                                                 // must not fail - we should never end up in a state where we
2659                                                                 // double-fail an HTLC or fail-then-claim an HTLC as it indicates
2660                                                                 // we didn't wait for a full revocation before failing.
2661                                                                 update_fail_htlcs.push(update_fail_msg_option.unwrap())
2662                                                         },
2663                                                         Err(e) => {
2664                                                                 if let ChannelError::Ignore(_) = e {}
2665                                                                 else {
2666                                                                         panic!("Got a non-IgnoreError action trying to fail holding cell HTLC");
2667                                                                 }
2668                                                         }
2669                                                 }
2670                                         },
2671                                 }
2672                         }
2673                         if update_add_htlcs.is_empty() && update_fulfill_htlcs.is_empty() && update_fail_htlcs.is_empty() && self.holding_cell_update_fee.is_none() {
2674                                 return Ok((None, htlcs_to_fail));
2675                         }
2676                         let update_fee = if let Some(feerate) = self.holding_cell_update_fee.take() {
2677                                 assert!(self.is_outbound());
2678                                 self.pending_update_fee = Some((feerate, FeeUpdateState::Outbound));
2679                                 Some(msgs::UpdateFee {
2680                                         channel_id: self.channel_id,
2681                                         feerate_per_kw: feerate as u32,
2682                                 })
2683                         } else {
2684                                 None
2685                         };
2686
2687                         let (commitment_signed, mut additional_update) = self.send_commitment_no_status_check(logger)?;
2688                         // send_commitment_no_status_check and get_update_fulfill_htlc may bump latest_monitor_id
2689                         // but we want them to be strictly increasing by one, so reset it here.
2690                         self.latest_monitor_update_id = monitor_update.update_id;
2691                         monitor_update.updates.append(&mut additional_update.updates);
2692
2693                         log_debug!(logger, "Freeing holding cell in channel {} resulted in {}{} HTLCs added, {} HTLCs fulfilled, and {} HTLCs failed.",
2694                                 log_bytes!(self.channel_id()), if update_fee.is_some() { "a fee update, " } else { "" },
2695                                 update_add_htlcs.len(), update_fulfill_htlcs.len(), update_fail_htlcs.len());
2696
2697                         Ok((Some((msgs::CommitmentUpdate {
2698                                 update_add_htlcs,
2699                                 update_fulfill_htlcs,
2700                                 update_fail_htlcs,
2701                                 update_fail_malformed_htlcs: Vec::new(),
2702                                 update_fee,
2703                                 commitment_signed,
2704                         }, monitor_update)), htlcs_to_fail))
2705                 } else {
2706                         Ok((None, Vec::new()))
2707                 }
2708         }
2709
2710         /// Handles receiving a remote's revoke_and_ack. Note that we may return a new
2711         /// commitment_signed message here in case we had pending outbound HTLCs to add which were
2712         /// waiting on this revoke_and_ack. The generation of this new commitment_signed may also fail,
2713         /// generating an appropriate error *after* the channel state has been updated based on the
2714         /// revoke_and_ack message.
2715         pub fn revoke_and_ack<L: Deref>(&mut self, msg: &msgs::RevokeAndACK, logger: &L) -> Result<(Option<msgs::CommitmentUpdate>, Vec<(PendingHTLCInfo, u64)>, Vec<(HTLCSource, PaymentHash, HTLCFailReason)>, ChannelMonitorUpdate, Vec<(HTLCSource, PaymentHash)>), ChannelError>
2716                 where L::Target: Logger,
2717         {
2718                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
2719                         return Err(ChannelError::Close("Got revoke/ACK message when channel was not in an operational state".to_owned()));
2720                 }
2721                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2722                         return Err(ChannelError::Close("Peer sent revoke_and_ack when we needed a channel_reestablish".to_owned()));
2723                 }
2724                 if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK == BOTH_SIDES_SHUTDOWN_MASK && self.last_sent_closing_fee.is_some() {
2725                         return Err(ChannelError::Close("Peer sent revoke_and_ack after we'd started exchanging closing_signeds".to_owned()));
2726                 }
2727
2728                 if let Some(counterparty_prev_commitment_point) = self.counterparty_prev_commitment_point {
2729                         if PublicKey::from_secret_key(&self.secp_ctx, &secp_check!(SecretKey::from_slice(&msg.per_commitment_secret), "Peer provided an invalid per_commitment_secret".to_owned())) != counterparty_prev_commitment_point {
2730                                 return Err(ChannelError::Close("Got a revoke commitment secret which didn't correspond to their current pubkey".to_owned()));
2731                         }
2732                 }
2733
2734                 if self.channel_state & ChannelState::AwaitingRemoteRevoke as u32 == 0 {
2735                         // Our counterparty seems to have burned their coins to us (by revoking a state when we
2736                         // haven't given them a new commitment transaction to broadcast). We should probably
2737                         // take advantage of this by updating our channel monitor, sending them an error, and
2738                         // waiting for them to broadcast their latest (now-revoked claim). But, that would be a
2739                         // lot of work, and there's some chance this is all a misunderstanding anyway.
2740                         // We have to do *something*, though, since our signer may get mad at us for otherwise
2741                         // jumping a remote commitment number, so best to just force-close and move on.
2742                         return Err(ChannelError::Close("Received an unexpected revoke_and_ack".to_owned()));
2743                 }
2744
2745                 #[cfg(any(test, feature = "fuzztarget"))]
2746                 {
2747                         *self.next_local_commitment_tx_fee_info_cached.lock().unwrap() = None;
2748                         *self.next_remote_commitment_tx_fee_info_cached.lock().unwrap() = None;
2749                 }
2750
2751                 self.commitment_secrets.provide_secret(self.cur_counterparty_commitment_transaction_number + 1, msg.per_commitment_secret)
2752                         .map_err(|_| ChannelError::Close("Previous secrets did not match new one".to_owned()))?;
2753                 self.latest_monitor_update_id += 1;
2754                 let mut monitor_update = ChannelMonitorUpdate {
2755                         update_id: self.latest_monitor_update_id,
2756                         updates: vec![ChannelMonitorUpdateStep::CommitmentSecret {
2757                                 idx: self.cur_counterparty_commitment_transaction_number + 1,
2758                                 secret: msg.per_commitment_secret,
2759                         }],
2760                 };
2761
2762                 // Update state now that we've passed all the can-fail calls...
2763                 // (note that we may still fail to generate the new commitment_signed message, but that's
2764                 // OK, we step the channel here and *then* if the new generation fails we can fail the
2765                 // channel based on that, but stepping stuff here should be safe either way.
2766                 self.channel_state &= !(ChannelState::AwaitingRemoteRevoke as u32);
2767                 self.counterparty_prev_commitment_point = self.counterparty_cur_commitment_point;
2768                 self.counterparty_cur_commitment_point = Some(msg.next_per_commitment_point);
2769                 self.cur_counterparty_commitment_transaction_number -= 1;
2770
2771                 log_trace!(logger, "Updating HTLCs on receipt of RAA in channel {}...", log_bytes!(self.channel_id()));
2772                 let mut to_forward_infos = Vec::new();
2773                 let mut revoked_htlcs = Vec::new();
2774                 let mut update_fail_htlcs = Vec::new();
2775                 let mut update_fail_malformed_htlcs = Vec::new();
2776                 let mut require_commitment = false;
2777                 let mut value_to_self_msat_diff: i64 = 0;
2778
2779                 {
2780                         // Take references explicitly so that we can hold multiple references to self.
2781                         let pending_inbound_htlcs: &mut Vec<_> = &mut self.pending_inbound_htlcs;
2782                         let pending_outbound_htlcs: &mut Vec<_> = &mut self.pending_outbound_htlcs;
2783
2784                         // We really shouldnt have two passes here, but retain gives a non-mutable ref (Rust bug)
2785                         pending_inbound_htlcs.retain(|htlc| {
2786                                 if let &InboundHTLCState::LocalRemoved(ref reason) = &htlc.state {
2787                                         log_trace!(logger, " ...removing inbound LocalRemoved {}", log_bytes!(htlc.payment_hash.0));
2788                                         if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
2789                                                 value_to_self_msat_diff += htlc.amount_msat as i64;
2790                                         }
2791                                         false
2792                                 } else { true }
2793                         });
2794                         pending_outbound_htlcs.retain(|htlc| {
2795                                 if let &OutboundHTLCState::AwaitingRemovedRemoteRevoke(ref fail_reason) = &htlc.state {
2796                                         log_trace!(logger, " ...removing outbound AwaitingRemovedRemoteRevoke {}", log_bytes!(htlc.payment_hash.0));
2797                                         if let Some(reason) = fail_reason.clone() { // We really want take() here, but, again, non-mut ref :(
2798                                                 revoked_htlcs.push((htlc.source.clone(), htlc.payment_hash, reason));
2799                                         } else {
2800                                                 // They fulfilled, so we sent them money
2801                                                 value_to_self_msat_diff -= htlc.amount_msat as i64;
2802                                         }
2803                                         false
2804                                 } else { true }
2805                         });
2806                         for htlc in pending_inbound_htlcs.iter_mut() {
2807                                 let swap = if let &InboundHTLCState::AwaitingRemoteRevokeToAnnounce(_) = &htlc.state {
2808                                         true
2809                                 } else if let &InboundHTLCState::AwaitingAnnouncedRemoteRevoke(_) = &htlc.state {
2810                                         true
2811                                 } else { false };
2812                                 if swap {
2813                                         let mut state = InboundHTLCState::Committed;
2814                                         mem::swap(&mut state, &mut htlc.state);
2815
2816                                         if let InboundHTLCState::AwaitingRemoteRevokeToAnnounce(forward_info) = state {
2817                                                 log_trace!(logger, " ...promoting inbound AwaitingRemoteRevokeToAnnounce {} to AwaitingAnnouncedRemoteRevoke", log_bytes!(htlc.payment_hash.0));
2818                                                 htlc.state = InboundHTLCState::AwaitingAnnouncedRemoteRevoke(forward_info);
2819                                                 require_commitment = true;
2820                                         } else if let InboundHTLCState::AwaitingAnnouncedRemoteRevoke(forward_info) = state {
2821                                                 match forward_info {
2822                                                         PendingHTLCStatus::Fail(fail_msg) => {
2823                                                                 log_trace!(logger, " ...promoting inbound AwaitingAnnouncedRemoteRevoke {} to LocalRemoved due to PendingHTLCStatus indicating failure", log_bytes!(htlc.payment_hash.0));
2824                                                                 require_commitment = true;
2825                                                                 match fail_msg {
2826                                                                         HTLCFailureMsg::Relay(msg) => {
2827                                                                                 htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::FailRelay(msg.reason.clone()));
2828                                                                                 update_fail_htlcs.push(msg)
2829                                                                         },
2830                                                                         HTLCFailureMsg::Malformed(msg) => {
2831                                                                                 htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::FailMalformed((msg.sha256_of_onion, msg.failure_code)));
2832                                                                                 update_fail_malformed_htlcs.push(msg)
2833                                                                         },
2834                                                                 }
2835                                                         },
2836                                                         PendingHTLCStatus::Forward(forward_info) => {
2837                                                                 log_trace!(logger, " ...promoting inbound AwaitingAnnouncedRemoteRevoke {} to Committed", log_bytes!(htlc.payment_hash.0));
2838                                                                 to_forward_infos.push((forward_info, htlc.htlc_id));
2839                                                                 htlc.state = InboundHTLCState::Committed;
2840                                                         }
2841                                                 }
2842                                         }
2843                                 }
2844                         }
2845                         for htlc in pending_outbound_htlcs.iter_mut() {
2846                                 if let OutboundHTLCState::LocalAnnounced(_) = htlc.state {
2847                                         log_trace!(logger, " ...promoting outbound LocalAnnounced {} to Committed", log_bytes!(htlc.payment_hash.0));
2848                                         htlc.state = OutboundHTLCState::Committed;
2849                                 }
2850                                 if let Some(fail_reason) = if let &mut OutboundHTLCState::AwaitingRemoteRevokeToRemove(ref mut fail_reason) = &mut htlc.state {
2851                                         Some(fail_reason.take())
2852                                 } else { None } {
2853                                         log_trace!(logger, " ...promoting outbound AwaitingRemoteRevokeToRemove {} to AwaitingRemovedRemoteRevoke", log_bytes!(htlc.payment_hash.0));
2854                                         htlc.state = OutboundHTLCState::AwaitingRemovedRemoteRevoke(fail_reason);
2855                                         require_commitment = true;
2856                                 }
2857                         }
2858                 }
2859                 self.value_to_self_msat = (self.value_to_self_msat as i64 + value_to_self_msat_diff) as u64;
2860
2861                 if let Some((feerate, update_state)) = self.pending_update_fee {
2862                         match update_state {
2863                                 FeeUpdateState::Outbound => {
2864                                         debug_assert!(self.is_outbound());
2865                                         log_trace!(logger, " ...promoting outbound fee update {} to Committed", feerate);
2866                                         self.feerate_per_kw = feerate;
2867                                         self.pending_update_fee = None;
2868                                 },
2869                                 FeeUpdateState::RemoteAnnounced => { debug_assert!(!self.is_outbound()); },
2870                                 FeeUpdateState::AwaitingRemoteRevokeToAnnounce => {
2871                                         debug_assert!(!self.is_outbound());
2872                                         log_trace!(logger, " ...promoting inbound AwaitingRemoteRevokeToAnnounce fee update {} to Committed", feerate);
2873                                         require_commitment = true;
2874                                         self.feerate_per_kw = feerate;
2875                                         self.pending_update_fee = None;
2876                                 },
2877                         }
2878                 }
2879
2880                 if (self.channel_state & ChannelState::MonitorUpdateFailed as u32) == ChannelState::MonitorUpdateFailed as u32 {
2881                         // We can't actually generate a new commitment transaction (incl by freeing holding
2882                         // cells) while we can't update the monitor, so we just return what we have.
2883                         if require_commitment {
2884                                 self.monitor_pending_commitment_signed = true;
2885                                 // When the monitor updating is restored we'll call get_last_commitment_update(),
2886                                 // which does not update state, but we're definitely now awaiting a remote revoke
2887                                 // before we can step forward any more, so set it here.
2888                                 let (_, mut additional_update) = self.send_commitment_no_status_check(logger)?;
2889                                 // send_commitment_no_status_check may bump latest_monitor_id but we want them to be
2890                                 // strictly increasing by one, so decrement it here.
2891                                 self.latest_monitor_update_id = monitor_update.update_id;
2892                                 monitor_update.updates.append(&mut additional_update.updates);
2893                         }
2894                         self.monitor_pending_forwards.append(&mut to_forward_infos);
2895                         self.monitor_pending_failures.append(&mut revoked_htlcs);
2896                         log_debug!(logger, "Received a valid revoke_and_ack for channel {} but awaiting a monitor update resolution to reply.", log_bytes!(self.channel_id()));
2897                         return Ok((None, Vec::new(), Vec::new(), monitor_update, Vec::new()))
2898                 }
2899
2900                 match self.free_holding_cell_htlcs(logger)? {
2901                         (Some((mut commitment_update, mut additional_update)), htlcs_to_fail) => {
2902                                 commitment_update.update_fail_htlcs.reserve(update_fail_htlcs.len());
2903                                 for fail_msg in update_fail_htlcs.drain(..) {
2904                                         commitment_update.update_fail_htlcs.push(fail_msg);
2905                                 }
2906                                 commitment_update.update_fail_malformed_htlcs.reserve(update_fail_malformed_htlcs.len());
2907                                 for fail_msg in update_fail_malformed_htlcs.drain(..) {
2908                                         commitment_update.update_fail_malformed_htlcs.push(fail_msg);
2909                                 }
2910
2911                                 // free_holding_cell_htlcs may bump latest_monitor_id multiple times but we want them to be
2912                                 // strictly increasing by one, so decrement it here.
2913                                 self.latest_monitor_update_id = monitor_update.update_id;
2914                                 monitor_update.updates.append(&mut additional_update.updates);
2915
2916                                 Ok((Some(commitment_update), to_forward_infos, revoked_htlcs, monitor_update, htlcs_to_fail))
2917                         },
2918                         (None, htlcs_to_fail) => {
2919                                 if require_commitment {
2920                                         let (commitment_signed, mut additional_update) = self.send_commitment_no_status_check(logger)?;
2921
2922                                         // send_commitment_no_status_check may bump latest_monitor_id but we want them to be
2923                                         // strictly increasing by one, so decrement it here.
2924                                         self.latest_monitor_update_id = monitor_update.update_id;
2925                                         monitor_update.updates.append(&mut additional_update.updates);
2926
2927                                         log_debug!(logger, "Received a valid revoke_and_ack for channel {}. Responding with a commitment update with {} HTLCs failed.",
2928                                                 log_bytes!(self.channel_id()), update_fail_htlcs.len() + update_fail_malformed_htlcs.len());
2929                                         Ok((Some(msgs::CommitmentUpdate {
2930                                                 update_add_htlcs: Vec::new(),
2931                                                 update_fulfill_htlcs: Vec::new(),
2932                                                 update_fail_htlcs,
2933                                                 update_fail_malformed_htlcs,
2934                                                 update_fee: None,
2935                                                 commitment_signed
2936                                         }), to_forward_infos, revoked_htlcs, monitor_update, htlcs_to_fail))
2937                                 } else {
2938                                         log_debug!(logger, "Received a valid revoke_and_ack for channel {} with no reply necessary.", log_bytes!(self.channel_id()));
2939                                         Ok((None, to_forward_infos, revoked_htlcs, monitor_update, htlcs_to_fail))
2940                                 }
2941                         }
2942                 }
2943         }
2944
2945         /// Adds a pending update to this channel. See the doc for send_htlc for
2946         /// further details on the optionness of the return value.
2947         /// You MUST call send_commitment prior to any other calls on this Channel
2948         fn send_update_fee(&mut self, feerate_per_kw: u32) -> Option<msgs::UpdateFee> {
2949                 if !self.is_outbound() {
2950                         panic!("Cannot send fee from inbound channel");
2951                 }
2952                 if !self.is_usable() {
2953                         panic!("Cannot update fee until channel is fully established and we haven't started shutting down");
2954                 }
2955                 if !self.is_live() {
2956                         panic!("Cannot update fee while peer is disconnected/we're awaiting a monitor update (ChannelManager should have caught this)");
2957                 }
2958
2959                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::MonitorUpdateFailed as u32)) != 0 {
2960                         self.holding_cell_update_fee = Some(feerate_per_kw);
2961                         return None;
2962                 }
2963
2964                 debug_assert!(self.pending_update_fee.is_none());
2965                 self.pending_update_fee = Some((feerate_per_kw, FeeUpdateState::Outbound));
2966
2967                 Some(msgs::UpdateFee {
2968                         channel_id: self.channel_id,
2969                         feerate_per_kw,
2970                 })
2971         }
2972
2973         pub fn send_update_fee_and_commit<L: Deref>(&mut self, feerate_per_kw: u32, logger: &L) -> Result<Option<(msgs::UpdateFee, msgs::CommitmentSigned, ChannelMonitorUpdate)>, ChannelError> where L::Target: Logger {
2974                 match self.send_update_fee(feerate_per_kw) {
2975                         Some(update_fee) => {
2976                                 let (commitment_signed, monitor_update) = self.send_commitment_no_status_check(logger)?;
2977                                 Ok(Some((update_fee, commitment_signed, monitor_update)))
2978                         },
2979                         None => Ok(None)
2980                 }
2981         }
2982
2983         /// Removes any uncommitted inbound HTLCs and resets the state of uncommitted outbound HTLC
2984         /// updates, to be used on peer disconnection. After this, update_*_htlc messages need to be
2985         /// resent.
2986         /// No further message handling calls may be made until a channel_reestablish dance has
2987         /// completed.
2988         pub fn remove_uncommitted_htlcs_and_mark_paused<L: Deref>(&mut self, logger: &L)  where L::Target: Logger {
2989                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
2990                 if self.channel_state < ChannelState::FundingSent as u32 {
2991                         self.channel_state = ChannelState::ShutdownComplete as u32;
2992                         return;
2993                 }
2994                 // Upon reconnect we have to start the closing_signed dance over, but shutdown messages
2995                 // will be retransmitted.
2996                 self.last_sent_closing_fee = None;
2997                 self.pending_counterparty_closing_signed = None;
2998                 self.closing_fee_limits = None;
2999
3000                 let mut inbound_drop_count = 0;
3001                 self.pending_inbound_htlcs.retain(|htlc| {
3002                         match htlc.state {
3003                                 InboundHTLCState::RemoteAnnounced(_) => {
3004                                         // They sent us an update_add_htlc but we never got the commitment_signed.
3005                                         // We'll tell them what commitment_signed we're expecting next and they'll drop
3006                                         // this HTLC accordingly
3007                                         inbound_drop_count += 1;
3008                                         false
3009                                 },
3010                                 InboundHTLCState::AwaitingRemoteRevokeToAnnounce(_)|InboundHTLCState::AwaitingAnnouncedRemoteRevoke(_) => {
3011                                         // We received a commitment_signed updating this HTLC and (at least hopefully)
3012                                         // sent a revoke_and_ack (which we can re-transmit) and have heard nothing
3013                                         // in response to it yet, so don't touch it.
3014                                         true
3015                                 },
3016                                 InboundHTLCState::Committed => true,
3017                                 InboundHTLCState::LocalRemoved(_) => {
3018                                         // We (hopefully) sent a commitment_signed updating this HTLC (which we can
3019                                         // re-transmit if needed) and they may have even sent a revoke_and_ack back
3020                                         // (that we missed). Keep this around for now and if they tell us they missed
3021                                         // the commitment_signed we can re-transmit the update then.
3022                                         true
3023                                 },
3024                         }
3025                 });
3026                 self.next_counterparty_htlc_id -= inbound_drop_count;
3027
3028                 if let Some((_, update_state)) = self.pending_update_fee {
3029                         if update_state == FeeUpdateState::RemoteAnnounced {
3030                                 debug_assert!(!self.is_outbound());
3031                                 self.pending_update_fee = None;
3032                         }
3033                 }
3034
3035                 for htlc in self.pending_outbound_htlcs.iter_mut() {
3036                         if let OutboundHTLCState::RemoteRemoved(_) = htlc.state {
3037                                 // They sent us an update to remove this but haven't yet sent the corresponding
3038                                 // commitment_signed, we need to move it back to Committed and they can re-send
3039                                 // the update upon reconnection.
3040                                 htlc.state = OutboundHTLCState::Committed;
3041                         }
3042                 }
3043
3044                 self.channel_state |= ChannelState::PeerDisconnected as u32;
3045                 log_trace!(logger, "Peer disconnection resulted in {} remote-announced HTLC drops on channel {}", inbound_drop_count, log_bytes!(self.channel_id()));
3046         }
3047
3048         /// Indicates that a ChannelMonitor update failed to be stored by the client and further
3049         /// updates are partially paused.
3050         /// This must be called immediately after the call which generated the ChannelMonitor update
3051         /// which failed. The messages which were generated from that call which generated the
3052         /// monitor update failure must *not* have been sent to the remote end, and must instead
3053         /// have been dropped. They will be regenerated when monitor_updating_restored is called.
3054         pub fn monitor_update_failed(&mut self, resend_raa: bool, resend_commitment: bool, mut pending_forwards: Vec<(PendingHTLCInfo, u64)>, mut pending_fails: Vec<(HTLCSource, PaymentHash, HTLCFailReason)>) {
3055                 assert_eq!(self.channel_state & ChannelState::MonitorUpdateFailed as u32, 0);
3056                 self.monitor_pending_revoke_and_ack = resend_raa;
3057                 self.monitor_pending_commitment_signed = resend_commitment;
3058                 assert!(self.monitor_pending_forwards.is_empty());
3059                 mem::swap(&mut pending_forwards, &mut self.monitor_pending_forwards);
3060                 assert!(self.monitor_pending_failures.is_empty());
3061                 mem::swap(&mut pending_fails, &mut self.monitor_pending_failures);
3062                 self.channel_state |= ChannelState::MonitorUpdateFailed as u32;
3063         }
3064
3065         /// Indicates that the latest ChannelMonitor update has been committed by the client
3066         /// successfully and we should restore normal operation. Returns messages which should be sent
3067         /// to the remote side.
3068         pub fn monitor_updating_restored<L: Deref>(&mut self, logger: &L) -> (Option<msgs::RevokeAndACK>, Option<msgs::CommitmentUpdate>, RAACommitmentOrder, Vec<(PendingHTLCInfo, u64)>, Vec<(HTLCSource, PaymentHash, HTLCFailReason)>, Option<Transaction>, Option<msgs::FundingLocked>) where L::Target: Logger {
3069                 assert_eq!(self.channel_state & ChannelState::MonitorUpdateFailed as u32, ChannelState::MonitorUpdateFailed as u32);
3070                 self.channel_state &= !(ChannelState::MonitorUpdateFailed as u32);
3071
3072                 let funding_broadcastable = if self.channel_state & (ChannelState::FundingSent as u32) != 0 && self.is_outbound() {
3073                         self.funding_transaction.take()
3074                 } else { None };
3075
3076                 // We will never broadcast the funding transaction when we're in MonitorUpdateFailed (and
3077                 // we assume the user never directly broadcasts the funding transaction and waits for us to
3078                 // do it). Thus, we can only ever hit monitor_pending_funding_locked when we're an inbound
3079                 // channel which failed to persist the monitor on funding_created, and we got the funding
3080                 // transaction confirmed before the monitor was persisted.
3081                 let funding_locked = if self.monitor_pending_funding_locked {
3082                         assert!(!self.is_outbound(), "Funding transaction broadcast by the local client before it should have - LDK didn't do it!");
3083                         self.monitor_pending_funding_locked = false;
3084                         let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
3085                         Some(msgs::FundingLocked {
3086                                 channel_id: self.channel_id(),
3087                                 next_per_commitment_point,
3088                         })
3089                 } else { None };
3090
3091                 let mut forwards = Vec::new();
3092                 mem::swap(&mut forwards, &mut self.monitor_pending_forwards);
3093                 let mut failures = Vec::new();
3094                 mem::swap(&mut failures, &mut self.monitor_pending_failures);
3095
3096                 if self.channel_state & (ChannelState::PeerDisconnected as u32) != 0 {
3097                         self.monitor_pending_revoke_and_ack = false;
3098                         self.monitor_pending_commitment_signed = false;
3099                         return (None, None, RAACommitmentOrder::RevokeAndACKFirst, forwards, failures, funding_broadcastable, funding_locked);
3100                 }
3101
3102                 let raa = if self.monitor_pending_revoke_and_ack {
3103                         Some(self.get_last_revoke_and_ack())
3104                 } else { None };
3105                 let commitment_update = if self.monitor_pending_commitment_signed {
3106                         Some(self.get_last_commitment_update(logger))
3107                 } else { None };
3108
3109                 self.monitor_pending_revoke_and_ack = false;
3110                 self.monitor_pending_commitment_signed = false;
3111                 let order = self.resend_order.clone();
3112                 log_debug!(logger, "Restored monitor updating in channel {} resulting in {}{} commitment update and {} RAA, with {} first",
3113                         log_bytes!(self.channel_id()), if funding_broadcastable.is_some() { "a funding broadcastable, " } else { "" },
3114                         if commitment_update.is_some() { "a" } else { "no" }, if raa.is_some() { "an" } else { "no" },
3115                         match order { RAACommitmentOrder::CommitmentFirst => "commitment", RAACommitmentOrder::RevokeAndACKFirst => "RAA"});
3116                 (raa, commitment_update, order, forwards, failures, funding_broadcastable, funding_locked)
3117         }
3118
3119         pub fn update_fee<F: Deref>(&mut self, fee_estimator: &F, msg: &msgs::UpdateFee) -> Result<(), ChannelError>
3120                 where F::Target: FeeEstimator
3121         {
3122                 if self.is_outbound() {
3123                         return Err(ChannelError::Close("Non-funding remote tried to update channel fee".to_owned()));
3124                 }
3125                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
3126                         return Err(ChannelError::Close("Peer sent update_fee when we needed a channel_reestablish".to_owned()));
3127                 }
3128                 Channel::<Signer>::check_remote_fee(fee_estimator, msg.feerate_per_kw)?;
3129                 let feerate_over_dust_buffer = msg.feerate_per_kw > self.get_dust_buffer_feerate();
3130
3131                 self.pending_update_fee = Some((msg.feerate_per_kw, FeeUpdateState::RemoteAnnounced));
3132                 self.update_time_counter += 1;
3133                 // If the feerate has increased over the previous dust buffer (note that
3134                 // `get_dust_buffer_feerate` considers the `pending_update_fee` status), check that we
3135                 // won't be pushed over our dust exposure limit by the feerate increase.
3136                 if feerate_over_dust_buffer {
3137                         let inbound_stats = self.get_inbound_pending_htlc_stats();
3138                         let outbound_stats = self.get_outbound_pending_htlc_stats();
3139                         let holder_tx_dust_exposure = inbound_stats.on_holder_tx_dust_exposure_msat + outbound_stats.on_holder_tx_dust_exposure_msat;
3140                         let counterparty_tx_dust_exposure = inbound_stats.on_counterparty_tx_dust_exposure_msat + outbound_stats.on_counterparty_tx_dust_exposure_msat;
3141                         if holder_tx_dust_exposure > self.get_max_dust_htlc_exposure_msat() {
3142                                 return Err(ChannelError::Close(format!("Peer sent update_fee with a feerate ({}) which may over-expose us to dust-in-flight on our own transactions (totaling {} msat)",
3143                                         msg.feerate_per_kw, holder_tx_dust_exposure)));
3144                         }
3145                         if counterparty_tx_dust_exposure > self.get_max_dust_htlc_exposure_msat() {
3146                                 return Err(ChannelError::Close(format!("Peer sent update_fee with a feerate ({}) which may over-expose us to dust-in-flight on our counterparty's transactions (totaling {} msat)",
3147                                         msg.feerate_per_kw, counterparty_tx_dust_exposure)));
3148                         }
3149                 }
3150                 Ok(())
3151         }
3152
3153         fn get_last_revoke_and_ack(&self) -> msgs::RevokeAndACK {
3154                 let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
3155                 let per_commitment_secret = self.holder_signer.release_commitment_secret(self.cur_holder_commitment_transaction_number + 2);
3156                 msgs::RevokeAndACK {
3157                         channel_id: self.channel_id,
3158                         per_commitment_secret,
3159                         next_per_commitment_point,
3160                 }
3161         }
3162
3163         fn get_last_commitment_update<L: Deref>(&self, logger: &L) -> msgs::CommitmentUpdate where L::Target: Logger {
3164                 let mut update_add_htlcs = Vec::new();
3165                 let mut update_fulfill_htlcs = Vec::new();
3166                 let mut update_fail_htlcs = Vec::new();
3167                 let mut update_fail_malformed_htlcs = Vec::new();
3168
3169                 for htlc in self.pending_outbound_htlcs.iter() {
3170                         if let &OutboundHTLCState::LocalAnnounced(ref onion_packet) = &htlc.state {
3171                                 update_add_htlcs.push(msgs::UpdateAddHTLC {
3172                                         channel_id: self.channel_id(),
3173                                         htlc_id: htlc.htlc_id,
3174                                         amount_msat: htlc.amount_msat,
3175                                         payment_hash: htlc.payment_hash,
3176                                         cltv_expiry: htlc.cltv_expiry,
3177                                         onion_routing_packet: (**onion_packet).clone(),
3178                                 });
3179                         }
3180                 }
3181
3182                 for htlc in self.pending_inbound_htlcs.iter() {
3183                         if let &InboundHTLCState::LocalRemoved(ref reason) = &htlc.state {
3184                                 match reason {
3185                                         &InboundHTLCRemovalReason::FailRelay(ref err_packet) => {
3186                                                 update_fail_htlcs.push(msgs::UpdateFailHTLC {
3187                                                         channel_id: self.channel_id(),
3188                                                         htlc_id: htlc.htlc_id,
3189                                                         reason: err_packet.clone()
3190                                                 });
3191                                         },
3192                                         &InboundHTLCRemovalReason::FailMalformed((ref sha256_of_onion, ref failure_code)) => {
3193                                                 update_fail_malformed_htlcs.push(msgs::UpdateFailMalformedHTLC {
3194                                                         channel_id: self.channel_id(),
3195                                                         htlc_id: htlc.htlc_id,
3196                                                         sha256_of_onion: sha256_of_onion.clone(),
3197                                                         failure_code: failure_code.clone(),
3198                                                 });
3199                                         },
3200                                         &InboundHTLCRemovalReason::Fulfill(ref payment_preimage) => {
3201                                                 update_fulfill_htlcs.push(msgs::UpdateFulfillHTLC {
3202                                                         channel_id: self.channel_id(),
3203                                                         htlc_id: htlc.htlc_id,
3204                                                         payment_preimage: payment_preimage.clone(),
3205                                                 });
3206                                         },
3207                                 }
3208                         }
3209                 }
3210
3211                 let update_fee = if self.is_outbound() && self.pending_update_fee.is_some() {
3212                         Some(msgs::UpdateFee {
3213                                 channel_id: self.channel_id(),
3214                                 feerate_per_kw: self.pending_update_fee.unwrap().0,
3215                         })
3216                 } else { None };
3217
3218                 log_trace!(logger, "Regenerated latest commitment update in channel {} with{} {} update_adds, {} update_fulfills, {} update_fails, and {} update_fail_malformeds",
3219                                 log_bytes!(self.channel_id()), if update_fee.is_some() { " update_fee," } else { "" },
3220                                 update_add_htlcs.len(), update_fulfill_htlcs.len(), update_fail_htlcs.len(), update_fail_malformed_htlcs.len());
3221                 msgs::CommitmentUpdate {
3222                         update_add_htlcs, update_fulfill_htlcs, update_fail_htlcs, update_fail_malformed_htlcs, update_fee,
3223                         commitment_signed: self.send_commitment_no_state_update(logger).expect("It looks like we failed to re-generate a commitment_signed we had previously sent?").0,
3224                 }
3225         }
3226
3227         /// May panic if some calls other than message-handling calls (which will all Err immediately)
3228         /// have been called between remove_uncommitted_htlcs_and_mark_paused and this call.
3229         pub fn channel_reestablish<L: Deref>(&mut self, msg: &msgs::ChannelReestablish, logger: &L) -> Result<(Option<msgs::FundingLocked>, Option<msgs::RevokeAndACK>, Option<msgs::CommitmentUpdate>, Option<ChannelMonitorUpdate>, RAACommitmentOrder, Vec<(HTLCSource, PaymentHash)>, Option<msgs::Shutdown>), ChannelError> where L::Target: Logger {
3230                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == 0 {
3231                         // While BOLT 2 doesn't indicate explicitly we should error this channel here, it
3232                         // almost certainly indicates we are going to end up out-of-sync in some way, so we
3233                         // just close here instead of trying to recover.
3234                         return Err(ChannelError::Close("Peer sent a loose channel_reestablish not after reconnect".to_owned()));
3235                 }
3236
3237                 if msg.next_local_commitment_number >= INITIAL_COMMITMENT_NUMBER || msg.next_remote_commitment_number >= INITIAL_COMMITMENT_NUMBER ||
3238                         msg.next_local_commitment_number == 0 {
3239                         return Err(ChannelError::Close("Peer sent a garbage channel_reestablish".to_owned()));
3240                 }
3241
3242                 if msg.next_remote_commitment_number > 0 {
3243                         match msg.data_loss_protect {
3244                                 OptionalField::Present(ref data_loss) => {
3245                                         let expected_point = self.holder_signer.get_per_commitment_point(INITIAL_COMMITMENT_NUMBER - msg.next_remote_commitment_number + 1, &self.secp_ctx);
3246                                         let given_secret = SecretKey::from_slice(&data_loss.your_last_per_commitment_secret)
3247                                                 .map_err(|_| ChannelError::Close("Peer sent a garbage channel_reestablish with unparseable secret key".to_owned()))?;
3248                                         if expected_point != PublicKey::from_secret_key(&self.secp_ctx, &given_secret) {
3249                                                 return Err(ChannelError::Close("Peer sent a garbage channel_reestablish with secret key not matching the commitment height provided".to_owned()));
3250                                         }
3251                                         if msg.next_remote_commitment_number > INITIAL_COMMITMENT_NUMBER - self.cur_holder_commitment_transaction_number {
3252                                                 return Err(ChannelError::CloseDelayBroadcast(
3253                                                         "We have fallen behind - we have received proof that if we broadcast remote is going to claim our funds - we can't do any automated broadcasting".to_owned()
3254                                                 ));
3255                                         }
3256                                 },
3257                                 OptionalField::Absent => {}
3258                         }
3259                 }
3260
3261                 // Go ahead and unmark PeerDisconnected as various calls we may make check for it (and all
3262                 // remaining cases either succeed or ErrorMessage-fail).
3263                 self.channel_state &= !(ChannelState::PeerDisconnected as u32);
3264
3265                 let shutdown_msg = if self.channel_state & (ChannelState::LocalShutdownSent as u32) != 0 {
3266                         assert!(self.shutdown_scriptpubkey.is_some());
3267                         Some(msgs::Shutdown {
3268                                 channel_id: self.channel_id,
3269                                 scriptpubkey: self.get_closing_scriptpubkey(),
3270                         })
3271                 } else { None };
3272
3273                 if self.channel_state & (ChannelState::FundingSent as u32) == ChannelState::FundingSent as u32 {
3274                         // If we're waiting on a monitor update, we shouldn't re-send any funding_locked's.
3275                         if self.channel_state & (ChannelState::OurFundingLocked as u32) == 0 ||
3276                                         self.channel_state & (ChannelState::MonitorUpdateFailed as u32) != 0 {
3277                                 if msg.next_remote_commitment_number != 0 {
3278                                         return Err(ChannelError::Close("Peer claimed they saw a revoke_and_ack but we haven't sent funding_locked yet".to_owned()));
3279                                 }
3280                                 // Short circuit the whole handler as there is nothing we can resend them
3281                                 return Ok((None, None, None, None, RAACommitmentOrder::CommitmentFirst, Vec::new(), shutdown_msg));
3282                         }
3283
3284                         // We have OurFundingLocked set!
3285                         let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
3286                         return Ok((Some(msgs::FundingLocked {
3287                                 channel_id: self.channel_id(),
3288                                 next_per_commitment_point,
3289                         }), None, None, None, RAACommitmentOrder::CommitmentFirst, Vec::new(), shutdown_msg));
3290                 }
3291
3292                 let required_revoke = if msg.next_remote_commitment_number + 1 == INITIAL_COMMITMENT_NUMBER - self.cur_holder_commitment_transaction_number {
3293                         // Remote isn't waiting on any RevokeAndACK from us!
3294                         // Note that if we need to repeat our FundingLocked we'll do that in the next if block.
3295                         None
3296                 } else if msg.next_remote_commitment_number + 1 == (INITIAL_COMMITMENT_NUMBER - 1) - self.cur_holder_commitment_transaction_number {
3297                         if self.channel_state & (ChannelState::MonitorUpdateFailed as u32) != 0 {
3298                                 self.monitor_pending_revoke_and_ack = true;
3299                                 None
3300                         } else {
3301                                 Some(self.get_last_revoke_and_ack())
3302                         }
3303                 } else {
3304                         return Err(ChannelError::Close("Peer attempted to reestablish channel with a very old local commitment transaction".to_owned()));
3305                 };
3306
3307                 // We increment cur_counterparty_commitment_transaction_number only upon receipt of
3308                 // revoke_and_ack, not on sending commitment_signed, so we add one if have
3309                 // AwaitingRemoteRevoke set, which indicates we sent a commitment_signed but haven't gotten
3310                 // the corresponding revoke_and_ack back yet.
3311                 let next_counterparty_commitment_number = INITIAL_COMMITMENT_NUMBER - self.cur_counterparty_commitment_transaction_number + if (self.channel_state & ChannelState::AwaitingRemoteRevoke as u32) != 0 { 1 } else { 0 };
3312
3313                 let resend_funding_locked = if msg.next_local_commitment_number == 1 && INITIAL_COMMITMENT_NUMBER - self.cur_holder_commitment_transaction_number == 1 {
3314                         // We should never have to worry about MonitorUpdateFailed resending FundingLocked
3315                         let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
3316                         Some(msgs::FundingLocked {
3317                                 channel_id: self.channel_id(),
3318                                 next_per_commitment_point,
3319                         })
3320                 } else { None };
3321
3322                 if msg.next_local_commitment_number == next_counterparty_commitment_number {
3323                         if required_revoke.is_some() {
3324                                 log_debug!(logger, "Reconnected channel {} with only lost outbound RAA", log_bytes!(self.channel_id()));
3325                         } else {
3326                                 log_debug!(logger, "Reconnected channel {} with no loss", log_bytes!(self.channel_id()));
3327                         }
3328
3329                         if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::MonitorUpdateFailed as u32)) == 0 {
3330                                 // We're up-to-date and not waiting on a remote revoke (if we are our
3331                                 // channel_reestablish should result in them sending a revoke_and_ack), but we may
3332                                 // have received some updates while we were disconnected. Free the holding cell
3333                                 // now!
3334                                 match self.free_holding_cell_htlcs(logger) {
3335                                         Err(ChannelError::Close(msg)) => return Err(ChannelError::Close(msg)),
3336                                         Err(ChannelError::Warn(_)) | Err(ChannelError::Ignore(_)) | Err(ChannelError::CloseDelayBroadcast(_)) =>
3337                                                 panic!("Got non-channel-failing result from free_holding_cell_htlcs"),
3338                                         Ok((Some((commitment_update, monitor_update)), htlcs_to_fail)) => {
3339                                                 return Ok((resend_funding_locked, required_revoke, Some(commitment_update), Some(monitor_update), self.resend_order.clone(), htlcs_to_fail, shutdown_msg));
3340                                         },
3341                                         Ok((None, htlcs_to_fail)) => {
3342                                                 return Ok((resend_funding_locked, required_revoke, None, None, self.resend_order.clone(), htlcs_to_fail, shutdown_msg));
3343                                         },
3344                                 }
3345                         } else {
3346                                 return Ok((resend_funding_locked, required_revoke, None, None, self.resend_order.clone(), Vec::new(), shutdown_msg));
3347                         }
3348                 } else if msg.next_local_commitment_number == next_counterparty_commitment_number - 1 {
3349                         if required_revoke.is_some() {
3350                                 log_debug!(logger, "Reconnected channel {} with lost outbound RAA and lost remote commitment tx", log_bytes!(self.channel_id()));
3351                         } else {
3352                                 log_debug!(logger, "Reconnected channel {} with only lost remote commitment tx", log_bytes!(self.channel_id()));
3353                         }
3354
3355                         if self.channel_state & (ChannelState::MonitorUpdateFailed as u32) != 0 {
3356                                 self.monitor_pending_commitment_signed = true;
3357                                 return Ok((resend_funding_locked, None, None, None, self.resend_order.clone(), Vec::new(), shutdown_msg));
3358                         }
3359
3360                         return Ok((resend_funding_locked, required_revoke, Some(self.get_last_commitment_update(logger)), None, self.resend_order.clone(), Vec::new(), shutdown_msg));
3361                 } else {
3362                         return Err(ChannelError::Close("Peer attempted to reestablish channel with a very old remote commitment transaction".to_owned()));
3363                 }
3364         }
3365
3366         /// Calculates and returns our minimum and maximum closing transaction fee amounts, in whole
3367         /// satoshis. The amounts remain consistent unless a peer disconnects/reconnects or we restart,
3368         /// at which point they will be recalculated.
3369         fn calculate_closing_fee_limits<F: Deref>(&mut self, fee_estimator: &F) -> (u64, u64)
3370                 where F::Target: FeeEstimator
3371         {
3372                 if let Some((min, max)) = self.closing_fee_limits { return (min, max); }
3373
3374                 // Propose a range from our current Background feerate to our Normal feerate plus our
3375                 // force_close_avoidance_max_fee_satoshis.
3376                 // If we fail to come to consensus, we'll have to force-close.
3377                 let mut proposed_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background);
3378                 let normal_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Normal);
3379                 let mut proposed_max_feerate = if self.is_outbound() { normal_feerate } else { u32::max_value() };
3380
3381                 // The spec requires that (when the channel does not have anchors) we only send absolute
3382                 // channel fees no greater than the absolute channel fee on the current commitment
3383                 // transaction. It's unclear *which* commitment transaction this refers to, and there isn't
3384                 // very good reason to apply such a limit in any case. We don't bother doing so, risking
3385                 // some force-closure by old nodes, but we wanted to close the channel anyway.
3386
3387                 if let Some(target_feerate) = self.target_closing_feerate_sats_per_kw {
3388                         let min_feerate = if self.is_outbound() { target_feerate } else { cmp::min(self.feerate_per_kw, target_feerate) };
3389                         proposed_feerate = cmp::max(proposed_feerate, min_feerate);
3390                         proposed_max_feerate = cmp::max(proposed_max_feerate, min_feerate);
3391                 }
3392
3393                 // Note that technically we could end up with a lower minimum fee if one sides' balance is
3394                 // below our dust limit, causing the output to disappear. We don't bother handling this
3395                 // case, however, as this should only happen if a channel is closed before any (material)
3396                 // payments have been made on it. This may cause slight fee overpayment and/or failure to
3397                 // come to consensus with our counterparty on appropriate fees, however it should be a
3398                 // relatively rare case. We can revisit this later, though note that in order to determine
3399                 // if the funders' output is dust we have to know the absolute fee we're going to use.
3400                 let tx_weight = self.get_closing_transaction_weight(Some(&self.get_closing_scriptpubkey()), Some(self.counterparty_shutdown_scriptpubkey.as_ref().unwrap()));
3401                 let proposed_total_fee_satoshis = proposed_feerate as u64 * tx_weight / 1000;
3402                 let proposed_max_total_fee_satoshis = if self.is_outbound() {
3403                                 // We always add force_close_avoidance_max_fee_satoshis to our normal
3404                                 // feerate-calculated fee, but allow the max to be overridden if we're using a
3405                                 // target feerate-calculated fee.
3406                                 cmp::max(normal_feerate as u64 * tx_weight / 1000 + self.config.force_close_avoidance_max_fee_satoshis,
3407                                         proposed_max_feerate as u64 * tx_weight / 1000)
3408                         } else {
3409                                 u64::max_value()
3410                         };
3411
3412                 self.closing_fee_limits = Some((proposed_total_fee_satoshis, proposed_max_total_fee_satoshis));
3413                 self.closing_fee_limits.clone().unwrap()
3414         }
3415
3416         pub fn maybe_propose_closing_signed<F: Deref, L: Deref>(&mut self, fee_estimator: &F, logger: &L)
3417                 -> Result<(Option<msgs::ClosingSigned>, Option<Transaction>), ChannelError>
3418                 where F::Target: FeeEstimator, L::Target: Logger
3419         {
3420                 if !self.pending_inbound_htlcs.is_empty() || !self.pending_outbound_htlcs.is_empty() ||
3421                                 self.channel_state &
3422                                         (BOTH_SIDES_SHUTDOWN_MASK | ChannelState::AwaitingRemoteRevoke as u32 |
3423                                          ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32)
3424                                 != BOTH_SIDES_SHUTDOWN_MASK ||
3425                                 self.last_sent_closing_fee.is_some() || self.pending_update_fee.is_some() {
3426                         return Ok((None, None));
3427                 }
3428
3429                 if !self.is_outbound() {
3430                         if let Some(msg) = &self.pending_counterparty_closing_signed.take() {
3431                                 return self.closing_signed(fee_estimator, &msg);
3432                         }
3433                         return Ok((None, None));
3434                 }
3435
3436                 let (our_min_fee, our_max_fee) = self.calculate_closing_fee_limits(fee_estimator);
3437
3438                 assert!(self.shutdown_scriptpubkey.is_some());
3439                 let (closing_tx, total_fee_satoshis) = self.build_closing_transaction(our_min_fee, false);
3440                 log_trace!(logger, "Proposing initial closing_signed for our counterparty with a fee range of {}-{} sat (with initial proposal {} sats)",
3441                         our_min_fee, our_max_fee, total_fee_satoshis);
3442
3443                 let sig = self.holder_signer
3444                         .sign_closing_transaction(&closing_tx, &self.secp_ctx)
3445                         .map_err(|()| ChannelError::Close("Failed to get signature for closing transaction.".to_owned()))?;
3446
3447                 self.last_sent_closing_fee = Some((total_fee_satoshis, sig.clone()));
3448                 Ok((Some(msgs::ClosingSigned {
3449                         channel_id: self.channel_id,
3450                         fee_satoshis: total_fee_satoshis,
3451                         signature: sig,
3452                         fee_range: Some(msgs::ClosingSignedFeeRange {
3453                                 min_fee_satoshis: our_min_fee,
3454                                 max_fee_satoshis: our_max_fee,
3455                         }),
3456                 }), None))
3457         }
3458
3459         pub fn shutdown<K: Deref>(
3460                 &mut self, keys_provider: &K, their_features: &InitFeatures, msg: &msgs::Shutdown
3461         ) -> Result<(Option<msgs::Shutdown>, Option<ChannelMonitorUpdate>, Vec<(HTLCSource, PaymentHash)>), ChannelError>
3462         where K::Target: KeysInterface<Signer = Signer>
3463         {
3464                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
3465                         return Err(ChannelError::Close("Peer sent shutdown when we needed a channel_reestablish".to_owned()));
3466                 }
3467                 if self.channel_state < ChannelState::FundingSent as u32 {
3468                         // Spec says we should fail the connection, not the channel, but that's nonsense, there
3469                         // are plenty of reasons you may want to fail a channel pre-funding, and spec says you
3470                         // can do that via error message without getting a connection fail anyway...
3471                         return Err(ChannelError::Close("Peer sent shutdown pre-funding generation".to_owned()));
3472                 }
3473                 for htlc in self.pending_inbound_htlcs.iter() {
3474                         if let InboundHTLCState::RemoteAnnounced(_) = htlc.state {
3475                                 return Err(ChannelError::Close("Got shutdown with remote pending HTLCs".to_owned()));
3476                         }
3477                 }
3478                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
3479
3480                 let shutdown_scriptpubkey = match ShutdownScript::try_from((msg.scriptpubkey.clone(), their_features)) {
3481                         Ok(script) => script.into_inner(),
3482                         Err(_) => return Err(ChannelError::Close(format!("Got a nonstandard scriptpubkey ({}) from remote peer", msg.scriptpubkey.to_bytes().to_hex()))),
3483                 };
3484
3485                 if self.counterparty_shutdown_scriptpubkey.is_some() {
3486                         if Some(&shutdown_scriptpubkey) != self.counterparty_shutdown_scriptpubkey.as_ref() {
3487                                 return Err(ChannelError::Close(format!("Got shutdown request with a scriptpubkey ({}) which did not match their previous scriptpubkey.", shutdown_scriptpubkey.to_bytes().to_hex())));
3488                         }
3489                 } else {
3490                         self.counterparty_shutdown_scriptpubkey = Some(shutdown_scriptpubkey);
3491                 }
3492
3493                 // If we have any LocalAnnounced updates we'll probably just get back an update_fail_htlc
3494                 // immediately after the commitment dance, but we can send a Shutdown because we won't send
3495                 // any further commitment updates after we set LocalShutdownSent.
3496                 let send_shutdown = (self.channel_state & ChannelState::LocalShutdownSent as u32) != ChannelState::LocalShutdownSent as u32;
3497
3498                 let update_shutdown_script = match self.shutdown_scriptpubkey {
3499                         Some(_) => false,
3500                         None => {
3501                                 assert!(send_shutdown);
3502                                 let shutdown_scriptpubkey = keys_provider.get_shutdown_scriptpubkey();
3503                                 if !shutdown_scriptpubkey.is_compatible(their_features) {
3504                                         return Err(ChannelError::Close(format!("Provided a scriptpubkey format not accepted by peer: {}", shutdown_scriptpubkey)));
3505                                 }
3506                                 self.shutdown_scriptpubkey = Some(shutdown_scriptpubkey);
3507                                 true
3508                         },
3509                 };
3510
3511                 // From here on out, we may not fail!
3512
3513                 self.channel_state |= ChannelState::RemoteShutdownSent as u32;
3514                 self.update_time_counter += 1;
3515
3516                 let monitor_update = if update_shutdown_script {
3517                         self.latest_monitor_update_id += 1;
3518                         Some(ChannelMonitorUpdate {
3519                                 update_id: self.latest_monitor_update_id,
3520                                 updates: vec![ChannelMonitorUpdateStep::ShutdownScript {
3521                                         scriptpubkey: self.get_closing_scriptpubkey(),
3522                                 }],
3523                         })
3524                 } else { None };
3525                 let shutdown = if send_shutdown {
3526                         Some(msgs::Shutdown {
3527                                 channel_id: self.channel_id,
3528                                 scriptpubkey: self.get_closing_scriptpubkey(),
3529                         })
3530                 } else { None };
3531
3532                 // We can't send our shutdown until we've committed all of our pending HTLCs, but the
3533                 // remote side is unlikely to accept any new HTLCs, so we go ahead and "free" any holding
3534                 // cell HTLCs and return them to fail the payment.
3535                 self.holding_cell_update_fee = None;
3536                 let mut dropped_outbound_htlcs = Vec::with_capacity(self.holding_cell_htlc_updates.len());
3537                 self.holding_cell_htlc_updates.retain(|htlc_update| {
3538                         match htlc_update {
3539                                 &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, ref source, .. } => {
3540                                         dropped_outbound_htlcs.push((source.clone(), payment_hash.clone()));
3541                                         false
3542                                 },
3543                                 _ => true
3544                         }
3545                 });
3546
3547                 self.channel_state |= ChannelState::LocalShutdownSent as u32;
3548                 self.update_time_counter += 1;
3549
3550                 Ok((shutdown, monitor_update, dropped_outbound_htlcs))
3551         }
3552
3553         fn build_signed_closing_transaction(&self, tx: &mut Transaction, counterparty_sig: &Signature, sig: &Signature) {
3554                 if tx.input.len() != 1 { panic!("Tried to sign closing transaction that had input count != 1!"); }
3555                 if tx.input[0].witness.len() != 0 { panic!("Tried to re-sign closing transaction"); }
3556                 if tx.output.len() > 2 { panic!("Tried to sign bogus closing transaction"); }
3557
3558                 tx.input[0].witness.push(Vec::new()); // First is the multisig dummy
3559
3560                 let funding_key = self.get_holder_pubkeys().funding_pubkey.serialize();
3561                 let counterparty_funding_key = self.counterparty_funding_pubkey().serialize();
3562                 if funding_key[..] < counterparty_funding_key[..] {
3563                         tx.input[0].witness.push(sig.serialize_der().to_vec());
3564                         tx.input[0].witness.push(counterparty_sig.serialize_der().to_vec());
3565                 } else {
3566                         tx.input[0].witness.push(counterparty_sig.serialize_der().to_vec());
3567                         tx.input[0].witness.push(sig.serialize_der().to_vec());
3568                 }
3569                 tx.input[0].witness[1].push(SigHashType::All as u8);
3570                 tx.input[0].witness[2].push(SigHashType::All as u8);
3571
3572                 tx.input[0].witness.push(self.get_funding_redeemscript().into_bytes());
3573         }
3574
3575         pub fn closing_signed<F: Deref>(&mut self, fee_estimator: &F, msg: &msgs::ClosingSigned) -> Result<(Option<msgs::ClosingSigned>, Option<Transaction>), ChannelError>
3576                 where F::Target: FeeEstimator
3577         {
3578                 if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK != BOTH_SIDES_SHUTDOWN_MASK {
3579                         return Err(ChannelError::Close("Remote end sent us a closing_signed before both sides provided a shutdown".to_owned()));
3580                 }
3581                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
3582                         return Err(ChannelError::Close("Peer sent closing_signed when we needed a channel_reestablish".to_owned()));
3583                 }
3584                 if !self.pending_inbound_htlcs.is_empty() || !self.pending_outbound_htlcs.is_empty() {
3585                         return Err(ChannelError::Close("Remote end sent us a closing_signed while there were still pending HTLCs".to_owned()));
3586                 }
3587                 if msg.fee_satoshis > 21_000_000 * 1_0000_0000 { //this is required to stop potential overflow in build_closing_transaction
3588                         return Err(ChannelError::Close("Remote tried to send us a closing tx with > 21 million BTC fee".to_owned()));
3589                 }
3590
3591                 if self.is_outbound() && self.last_sent_closing_fee.is_none() {
3592                         return Err(ChannelError::Close("Remote tried to send a closing_signed when we were supposed to propose the first one".to_owned()));
3593                 }
3594
3595                 if self.channel_state & ChannelState::MonitorUpdateFailed as u32 != 0 {
3596                         self.pending_counterparty_closing_signed = Some(msg.clone());
3597                         return Ok((None, None));
3598                 }
3599
3600                 let funding_redeemscript = self.get_funding_redeemscript();
3601                 let (mut closing_tx, used_total_fee) = self.build_closing_transaction(msg.fee_satoshis, false);
3602                 if used_total_fee != msg.fee_satoshis {
3603                         return Err(ChannelError::Close(format!("Remote sent us a closing_signed with a fee greater than the value they can claim. Fee in message: {}", msg.fee_satoshis)));
3604                 }
3605                 let mut sighash = hash_to_message!(&bip143::SigHashCache::new(&closing_tx).signature_hash(0, &funding_redeemscript, self.channel_value_satoshis, SigHashType::All)[..]);
3606
3607                 match self.secp_ctx.verify(&sighash, &msg.signature, &self.get_counterparty_pubkeys().funding_pubkey) {
3608                         Ok(_) => {},
3609                         Err(_e) => {
3610                                 // The remote end may have decided to revoke their output due to inconsistent dust
3611                                 // limits, so check for that case by re-checking the signature here.
3612                                 closing_tx = self.build_closing_transaction(msg.fee_satoshis, true).0;
3613                                 sighash = hash_to_message!(&bip143::SigHashCache::new(&closing_tx).signature_hash(0, &funding_redeemscript, self.channel_value_satoshis, SigHashType::All)[..]);
3614                                 secp_check!(self.secp_ctx.verify(&sighash, &msg.signature, self.counterparty_funding_pubkey()), "Invalid closing tx signature from peer".to_owned());
3615                         },
3616                 };
3617
3618                 assert!(self.shutdown_scriptpubkey.is_some());
3619                 if let Some((last_fee, sig)) = self.last_sent_closing_fee {
3620                         if last_fee == msg.fee_satoshis {
3621                                 self.build_signed_closing_transaction(&mut closing_tx, &msg.signature, &sig);
3622                                 self.channel_state = ChannelState::ShutdownComplete as u32;
3623                                 self.update_time_counter += 1;
3624                                 return Ok((None, Some(closing_tx)));
3625                         }
3626                 }
3627
3628                 let (our_min_fee, our_max_fee) = self.calculate_closing_fee_limits(fee_estimator);
3629
3630                 macro_rules! propose_fee {
3631                         ($new_fee: expr) => {
3632                                 let (mut tx, used_fee) = if $new_fee == msg.fee_satoshis {
3633                                         (closing_tx, $new_fee)
3634                                 } else {
3635                                         self.build_closing_transaction($new_fee, false)
3636                                 };
3637
3638                                 let sig = self.holder_signer
3639                                         .sign_closing_transaction(&tx, &self.secp_ctx)
3640                                         .map_err(|_| ChannelError::Close("External signer refused to sign closing transaction".to_owned()))?;
3641
3642                                 let signed_tx = if $new_fee == msg.fee_satoshis {
3643                                         self.channel_state = ChannelState::ShutdownComplete as u32;
3644                                         self.update_time_counter += 1;
3645                                         self.build_signed_closing_transaction(&mut tx, &msg.signature, &sig);
3646                                         Some(tx)
3647                                 } else { None };
3648
3649                                 self.last_sent_closing_fee = Some((used_fee, sig.clone()));
3650                                 return Ok((Some(msgs::ClosingSigned {
3651                                         channel_id: self.channel_id,
3652                                         fee_satoshis: used_fee,
3653                                         signature: sig,
3654                                         fee_range: Some(msgs::ClosingSignedFeeRange {
3655                                                 min_fee_satoshis: our_min_fee,
3656                                                 max_fee_satoshis: our_max_fee,
3657                                         }),
3658                                 }), signed_tx))
3659                         }
3660                 }
3661
3662                 if let Some(msgs::ClosingSignedFeeRange { min_fee_satoshis, max_fee_satoshis }) = msg.fee_range {
3663                         if msg.fee_satoshis < min_fee_satoshis || msg.fee_satoshis > max_fee_satoshis {
3664                                 return Err(ChannelError::Close(format!("Peer sent a bogus closing_signed - suggested fee of {} sat was not in their desired range of {} sat - {} sat", msg.fee_satoshis, min_fee_satoshis, max_fee_satoshis)));
3665                         }
3666                         if max_fee_satoshis < our_min_fee {
3667                                 return Err(ChannelError::Warn(format!("Unable to come to consensus about closing feerate, remote's max fee ({} sat) was smaller than our min fee ({} sat)", max_fee_satoshis, our_min_fee)));
3668                         }
3669                         if min_fee_satoshis > our_max_fee {
3670                                 return Err(ChannelError::Warn(format!("Unable to come to consensus about closing feerate, remote's min fee ({} sat) was greater than our max fee ({} sat)", min_fee_satoshis, our_max_fee)));
3671                         }
3672
3673                         if !self.is_outbound() {
3674                                 // They have to pay, so pick the highest fee in the overlapping range.
3675                                 debug_assert_eq!(our_max_fee, u64::max_value()); // We should never set an upper bound
3676                                 propose_fee!(cmp::min(max_fee_satoshis, our_max_fee));
3677                         } else {
3678                                 if msg.fee_satoshis < our_min_fee || msg.fee_satoshis > our_max_fee {
3679                                         return Err(ChannelError::Close(format!("Peer sent a bogus closing_signed - suggested fee of {} sat was not in our desired range of {} sat - {} sat after we informed them of our range.",
3680                                                 msg.fee_satoshis, our_min_fee, our_max_fee)));
3681                                 }
3682                                 // The proposed fee is in our acceptable range, accept it and broadcast!
3683                                 propose_fee!(msg.fee_satoshis);
3684                         }
3685                 } else {
3686                         // Old fee style negotiation. We don't bother to enforce whether they are complying
3687                         // with the "making progress" requirements, we just comply and hope for the best.
3688                         if let Some((last_fee, _)) = self.last_sent_closing_fee {
3689                                 if msg.fee_satoshis > last_fee {
3690                                         if msg.fee_satoshis < our_max_fee {
3691                                                 propose_fee!(msg.fee_satoshis);
3692                                         } else if last_fee < our_max_fee {
3693                                                 propose_fee!(our_max_fee);
3694                                         } else {
3695                                                 return Err(ChannelError::Close(format!("Unable to come to consensus about closing feerate, remote wants something ({} sat) higher than our max fee ({} sat)", msg.fee_satoshis, our_max_fee)));
3696                                         }
3697                                 } else {
3698                                         if msg.fee_satoshis > our_min_fee {
3699                                                 propose_fee!(msg.fee_satoshis);
3700                                         } else if last_fee > our_min_fee {
3701                                                 propose_fee!(our_min_fee);
3702                                         } else {
3703                                                 return Err(ChannelError::Close(format!("Unable to come to consensus about closing feerate, remote wants something ({} sat) lower than our min fee ({} sat)", msg.fee_satoshis, our_min_fee)));
3704                                         }
3705                                 }
3706                         } else {
3707                                 if msg.fee_satoshis < our_min_fee {
3708                                         propose_fee!(our_min_fee);
3709                                 } else if msg.fee_satoshis > our_max_fee {
3710                                         propose_fee!(our_max_fee);
3711                                 } else {
3712                                         propose_fee!(msg.fee_satoshis);
3713                                 }
3714                         }
3715                 }
3716         }
3717
3718         // Public utilities:
3719
3720         pub fn channel_id(&self) -> [u8; 32] {
3721                 self.channel_id
3722         }
3723
3724         pub fn minimum_depth(&self) -> Option<u32> {
3725                 self.minimum_depth
3726         }
3727
3728         /// Gets the "user_id" value passed into the construction of this channel. It has no special
3729         /// meaning and exists only to allow users to have a persistent identifier of a channel.
3730         pub fn get_user_id(&self) -> u64 {
3731                 self.user_id
3732         }
3733
3734         /// Guaranteed to be Some after both FundingLocked messages have been exchanged (and, thus,
3735         /// is_usable() returns true).
3736         /// Allowed in any state (including after shutdown)
3737         pub fn get_short_channel_id(&self) -> Option<u64> {
3738                 self.short_channel_id
3739         }
3740
3741         /// Returns the funding_txo we either got from our peer, or were given by
3742         /// get_outbound_funding_created.
3743         pub fn get_funding_txo(&self) -> Option<OutPoint> {
3744                 self.channel_transaction_parameters.funding_outpoint
3745         }
3746
3747         fn get_holder_selected_contest_delay(&self) -> u16 {
3748                 self.channel_transaction_parameters.holder_selected_contest_delay
3749         }
3750
3751         fn get_holder_pubkeys(&self) -> &ChannelPublicKeys {
3752                 &self.channel_transaction_parameters.holder_pubkeys
3753         }
3754
3755         pub fn get_counterparty_selected_contest_delay(&self) -> Option<u16> {
3756                 self.channel_transaction_parameters.counterparty_parameters
3757                         .as_ref().map(|params| params.selected_contest_delay)
3758         }
3759
3760         fn get_counterparty_pubkeys(&self) -> &ChannelPublicKeys {
3761                 &self.channel_transaction_parameters.counterparty_parameters.as_ref().unwrap().pubkeys
3762         }
3763
3764         /// Allowed in any state (including after shutdown)
3765         pub fn get_counterparty_node_id(&self) -> PublicKey {
3766                 self.counterparty_node_id
3767         }
3768
3769         /// Allowed in any state (including after shutdown)
3770         #[cfg(test)]
3771         pub fn get_holder_htlc_minimum_msat(&self) -> u64 {
3772                 self.holder_htlc_minimum_msat
3773         }
3774
3775         /// Allowed in any state (including after shutdown)
3776         pub fn get_announced_htlc_max_msat(&self) -> u64 {
3777                 return cmp::min(
3778                         // Upper bound by capacity. We make it a bit less than full capacity to prevent attempts
3779                         // to use full capacity. This is an effort to reduce routing failures, because in many cases
3780                         // channel might have been used to route very small values (either by honest users or as DoS).
3781                         self.channel_value_satoshis * 1000 * 9 / 10,
3782
3783                         Channel::<Signer>::get_holder_max_htlc_value_in_flight_msat(self.channel_value_satoshis)
3784                 );
3785         }
3786
3787         /// Allowed in any state (including after shutdown)
3788         pub fn get_counterparty_htlc_minimum_msat(&self) -> u64 {
3789                 self.counterparty_htlc_minimum_msat
3790         }
3791
3792         pub fn get_value_satoshis(&self) -> u64 {
3793                 self.channel_value_satoshis
3794         }
3795
3796         pub fn get_fee_proportional_millionths(&self) -> u32 {
3797                 self.config.forwarding_fee_proportional_millionths
3798         }
3799
3800         pub fn get_cltv_expiry_delta(&self) -> u16 {
3801                 cmp::max(self.config.cltv_expiry_delta, MIN_CLTV_EXPIRY_DELTA)
3802         }
3803
3804         pub fn get_max_dust_htlc_exposure_msat(&self) -> u64 {
3805                 self.config.max_dust_htlc_exposure_msat
3806         }
3807
3808         pub fn get_feerate(&self) -> u32 {
3809                 self.feerate_per_kw
3810         }
3811
3812         pub fn get_dust_buffer_feerate(&self) -> u32 {
3813                 // When calculating our exposure to dust HTLCs, we assume that the channel feerate
3814                 // may, at any point, increase by at least 10 sat/vB (i.e 2530 sat/kWU) or 25%,
3815                 // whichever is higher. This ensures that we aren't suddenly exposed to significantly
3816                 // more dust balance if the feerate increases when we have several HTLCs pending
3817                 // which are near the dust limit.
3818                 let mut feerate_per_kw = self.feerate_per_kw;
3819                 if let Some((feerate, _)) = self.pending_update_fee {
3820                         feerate_per_kw = cmp::max(feerate_per_kw, feerate);
3821                 }
3822                 cmp::max(2530, feerate_per_kw * 1250 / 1000)
3823         }
3824
3825         pub fn get_cur_holder_commitment_transaction_number(&self) -> u64 {
3826                 self.cur_holder_commitment_transaction_number + 1
3827         }
3828
3829         pub fn get_cur_counterparty_commitment_transaction_number(&self) -> u64 {
3830                 self.cur_counterparty_commitment_transaction_number + 1 - if self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32) != 0 { 1 } else { 0 }
3831         }
3832
3833         pub fn get_revoked_counterparty_commitment_transaction_number(&self) -> u64 {
3834                 self.cur_counterparty_commitment_transaction_number + 2
3835         }
3836
3837         #[cfg(test)]
3838         pub fn get_signer(&self) -> &Signer {
3839                 &self.holder_signer
3840         }
3841
3842         #[cfg(test)]
3843         pub fn get_value_stat(&self) -> ChannelValueStat {
3844                 ChannelValueStat {
3845                         value_to_self_msat: self.value_to_self_msat,
3846                         channel_value_msat: self.channel_value_satoshis * 1000,
3847                         channel_reserve_msat: self.counterparty_selected_channel_reserve_satoshis.unwrap() * 1000,
3848                         pending_outbound_htlcs_amount_msat: self.pending_outbound_htlcs.iter().map(|ref h| h.amount_msat).sum::<u64>(),
3849                         pending_inbound_htlcs_amount_msat: self.pending_inbound_htlcs.iter().map(|ref h| h.amount_msat).sum::<u64>(),
3850                         holding_cell_outbound_amount_msat: {
3851                                 let mut res = 0;
3852                                 for h in self.holding_cell_htlc_updates.iter() {
3853                                         match h {
3854                                                 &HTLCUpdateAwaitingACK::AddHTLC{amount_msat, .. } => {
3855                                                         res += amount_msat;
3856                                                 }
3857                                                 _ => {}
3858                                         }
3859                                 }
3860                                 res
3861                         },
3862                         counterparty_max_htlc_value_in_flight_msat: self.counterparty_max_htlc_value_in_flight_msat,
3863                         counterparty_dust_limit_msat: self.counterparty_dust_limit_satoshis * 1000,
3864                 }
3865         }
3866
3867         /// Allowed in any state (including after shutdown)
3868         pub fn get_update_time_counter(&self) -> u32 {
3869                 self.update_time_counter
3870         }
3871
3872         pub fn get_latest_monitor_update_id(&self) -> u64 {
3873                 self.latest_monitor_update_id
3874         }
3875
3876         pub fn should_announce(&self) -> bool {
3877                 self.config.announced_channel
3878         }
3879
3880         pub fn is_outbound(&self) -> bool {
3881                 self.channel_transaction_parameters.is_outbound_from_holder
3882         }
3883
3884         /// Gets the fee we'd want to charge for adding an HTLC output to this Channel
3885         /// Allowed in any state (including after shutdown)
3886         pub fn get_outbound_forwarding_fee_base_msat(&self) -> u32 {
3887                 self.config.forwarding_fee_base_msat
3888         }
3889
3890         /// Returns true if we've ever received a message from the remote end for this Channel
3891         pub fn have_received_message(&self) -> bool {
3892                 self.channel_state > (ChannelState::OurInitSent as u32)
3893         }
3894
3895         /// Returns true if this channel is fully established and not known to be closing.
3896         /// Allowed in any state (including after shutdown)
3897         pub fn is_usable(&self) -> bool {
3898                 let mask = ChannelState::ChannelFunded as u32 | BOTH_SIDES_SHUTDOWN_MASK;
3899                 (self.channel_state & mask) == (ChannelState::ChannelFunded as u32)
3900         }
3901
3902         /// Returns true if this channel is currently available for use. This is a superset of
3903         /// is_usable() and considers things like the channel being temporarily disabled.
3904         /// Allowed in any state (including after shutdown)
3905         pub fn is_live(&self) -> bool {
3906                 self.is_usable() && (self.channel_state & (ChannelState::PeerDisconnected as u32) == 0)
3907         }
3908
3909         /// Returns true if this channel has been marked as awaiting a monitor update to move forward.
3910         /// Allowed in any state (including after shutdown)
3911         pub fn is_awaiting_monitor_update(&self) -> bool {
3912                 (self.channel_state & ChannelState::MonitorUpdateFailed as u32) != 0
3913         }
3914
3915         /// Returns true if funding_created was sent/received.
3916         pub fn is_funding_initiated(&self) -> bool {
3917                 self.channel_state >= ChannelState::FundingSent as u32
3918         }
3919
3920         /// Returns true if our peer has either initiated or agreed to shut down the channel.
3921         pub fn received_shutdown(&self) -> bool {
3922                 (self.channel_state & ChannelState::RemoteShutdownSent as u32) != 0
3923         }
3924
3925         /// Returns true if we either initiated or agreed to shut down the channel.
3926         pub fn sent_shutdown(&self) -> bool {
3927                 (self.channel_state & ChannelState::LocalShutdownSent as u32) != 0
3928         }
3929
3930         /// Returns true if this channel is fully shut down. True here implies that no further actions
3931         /// may/will be taken on this channel, and thus this object should be freed. Any future changes
3932         /// will be handled appropriately by the chain monitor.
3933         pub fn is_shutdown(&self) -> bool {
3934                 if (self.channel_state & ChannelState::ShutdownComplete as u32) == ChannelState::ShutdownComplete as u32  {
3935                         assert!(self.channel_state == ChannelState::ShutdownComplete as u32);
3936                         true
3937                 } else { false }
3938         }
3939
3940         pub fn channel_update_status(&self) -> ChannelUpdateStatus {
3941                 self.channel_update_status
3942         }
3943
3944         pub fn set_channel_update_status(&mut self, status: ChannelUpdateStatus) {
3945                 self.channel_update_status = status;
3946         }
3947
3948         fn check_get_funding_locked(&mut self, height: u32) -> Option<msgs::FundingLocked> {
3949                 if self.funding_tx_confirmation_height == 0 {
3950                         return None;
3951                 }
3952
3953                 let funding_tx_confirmations = height as i64 - self.funding_tx_confirmation_height as i64 + 1;
3954                 if funding_tx_confirmations <= 0 {
3955                         self.funding_tx_confirmation_height = 0;
3956                 }
3957
3958                 if funding_tx_confirmations < self.minimum_depth.unwrap_or(0) as i64 {
3959                         return None;
3960                 }
3961
3962                 let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
3963                 let need_commitment_update = if non_shutdown_state == ChannelState::FundingSent as u32 {
3964                         self.channel_state |= ChannelState::OurFundingLocked as u32;
3965                         true
3966                 } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::TheirFundingLocked as u32) {
3967                         self.channel_state = ChannelState::ChannelFunded as u32 | (self.channel_state & MULTI_STATE_FLAGS);
3968                         self.update_time_counter += 1;
3969                         true
3970                 } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::OurFundingLocked as u32) {
3971                         // We got a reorg but not enough to trigger a force close, just ignore.
3972                         false
3973                 } else if self.channel_state < ChannelState::ChannelFunded as u32 {
3974                         panic!("Started confirming a channel in a state pre-FundingSent?: {}", self.channel_state);
3975                 } else {
3976                         // We got a reorg but not enough to trigger a force close, just ignore.
3977                         false
3978                 };
3979
3980                 if need_commitment_update {
3981                         if self.channel_state & (ChannelState::MonitorUpdateFailed as u32) == 0 {
3982                                 let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
3983                                 return Some(msgs::FundingLocked {
3984                                         channel_id: self.channel_id,
3985                                         next_per_commitment_point,
3986                                 });
3987                         } else {
3988                                 self.monitor_pending_funding_locked = true;
3989                         }
3990                 }
3991                 None
3992         }
3993
3994         /// When a transaction is confirmed, we check whether it is or spends the funding transaction
3995         /// In the first case, we store the confirmation height and calculating the short channel id.
3996         /// In the second, we simply return an Err indicating we need to be force-closed now.
3997         pub fn transactions_confirmed<L: Deref>(&mut self, block_hash: &BlockHash, height: u32, txdata: &TransactionData, logger: &L)
3998                         -> Result<Option<msgs::FundingLocked>, msgs::ErrorMessage> where L::Target: Logger {
3999                 let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
4000                 for &(index_in_block, tx) in txdata.iter() {
4001                         if let Some(funding_txo) = self.get_funding_txo() {
4002                                 // If we haven't yet sent a funding_locked, but are in FundingSent (ignoring
4003                                 // whether they've sent a funding_locked or not), check if we should send one.
4004                                 if non_shutdown_state & !(ChannelState::TheirFundingLocked as u32) == ChannelState::FundingSent as u32 {
4005                                         if tx.txid() == funding_txo.txid {
4006                                                 let txo_idx = funding_txo.index as usize;
4007                                                 if txo_idx >= tx.output.len() || tx.output[txo_idx].script_pubkey != self.get_funding_redeemscript().to_v0_p2wsh() ||
4008                                                                 tx.output[txo_idx].value != self.channel_value_satoshis {
4009                                                         if self.is_outbound() {
4010                                                                 // If we generated the funding transaction and it doesn't match what it
4011                                                                 // should, the client is really broken and we should just panic and
4012                                                                 // tell them off. That said, because hash collisions happen with high
4013                                                                 // probability in fuzztarget mode, if we're fuzzing we just close the
4014                                                                 // channel and move on.
4015                                                                 #[cfg(not(feature = "fuzztarget"))]
4016                                                                 panic!("Client called ChannelManager::funding_transaction_generated with bogus transaction!");
4017                                                         }
4018                                                         self.update_time_counter += 1;
4019                                                         return Err(msgs::ErrorMessage {
4020                                                                 channel_id: self.channel_id(),
4021                                                                 data: "funding tx had wrong script/value or output index".to_owned()
4022                                                         });
4023                                                 } else {
4024                                                         if self.is_outbound() {
4025                                                                 for input in tx.input.iter() {
4026                                                                         if input.witness.is_empty() {
4027                                                                                 // We generated a malleable funding transaction, implying we've
4028                                                                                 // just exposed ourselves to funds loss to our counterparty.
4029                                                                                 #[cfg(not(feature = "fuzztarget"))]
4030                                                                                 panic!("Client called ChannelManager::funding_transaction_generated with bogus transaction!");
4031                                                                         }
4032                                                                 }
4033                                                         }
4034                                                         self.funding_tx_confirmation_height = height;
4035                                                         self.funding_tx_confirmed_in = Some(*block_hash);
4036                                                         self.short_channel_id = match scid_from_parts(height as u64, index_in_block as u64, txo_idx as u64) {
4037                                                                 Ok(scid) => Some(scid),
4038                                                                 Err(_) => panic!("Block was bogus - either height was > 16 million, had > 16 million transactions, or had > 65k outputs"),
4039                                                         }
4040                                                 }
4041                                         }
4042                                         // If we allow 1-conf funding, we may need to check for funding_locked here and
4043                                         // send it immediately instead of waiting for a best_block_updated call (which
4044                                         // may have already happened for this block).
4045                                         if let Some(funding_locked) = self.check_get_funding_locked(height) {
4046                                                 log_info!(logger, "Sending a funding_locked to our peer for channel {}", log_bytes!(self.channel_id));
4047                                                 return Ok(Some(funding_locked));
4048                                         }
4049                                 }
4050                                 for inp in tx.input.iter() {
4051                                         if inp.previous_output == funding_txo.into_bitcoin_outpoint() {
4052                                                 log_info!(logger, "Detected channel-closing tx {} spending {}:{}, closing channel {}", tx.txid(), inp.previous_output.txid, inp.previous_output.vout, log_bytes!(self.channel_id()));
4053                                                 return Err(msgs::ErrorMessage {
4054                                                         channel_id: self.channel_id(),
4055                                                         data: "Commitment or closing transaction was confirmed on chain.".to_owned()
4056                                                 });
4057                                         }
4058                                 }
4059                         }
4060                 }
4061                 Ok(None)
4062         }
4063
4064         /// When a new block is connected, we check the height of the block against outbound holding
4065         /// cell HTLCs in case we need to give up on them prematurely and time them out. Everything
4066         /// else (e.g. commitment transaction broadcasts, HTLC transaction broadcasting, etc) is
4067         /// handled by the ChannelMonitor.
4068         ///
4069         /// If we return Err, the channel may have been closed, at which point the standard
4070         /// requirements apply - no calls may be made except those explicitly stated to be allowed
4071         /// post-shutdown.
4072         ///
4073         /// May return some HTLCs (and their payment_hash) which have timed out and should be failed
4074         /// back.
4075         pub fn best_block_updated<L: Deref>(&mut self, height: u32, highest_header_time: u32, logger: &L)
4076                         -> Result<(Option<msgs::FundingLocked>, Vec<(HTLCSource, PaymentHash)>), msgs::ErrorMessage> where L::Target: Logger {
4077                 let mut timed_out_htlcs = Vec::new();
4078                 let unforwarded_htlc_cltv_limit = height + HTLC_FAIL_BACK_BUFFER;
4079                 self.holding_cell_htlc_updates.retain(|htlc_update| {
4080                         match htlc_update {
4081                                 &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, ref source, ref cltv_expiry, .. } => {
4082                                         if *cltv_expiry <= unforwarded_htlc_cltv_limit {
4083                                                 timed_out_htlcs.push((source.clone(), payment_hash.clone()));
4084                                                 false
4085                                         } else { true }
4086                                 },
4087                                 _ => true
4088                         }
4089                 });
4090
4091                 self.update_time_counter = cmp::max(self.update_time_counter, highest_header_time);
4092
4093                 if let Some(funding_locked) = self.check_get_funding_locked(height) {
4094                         log_info!(logger, "Sending a funding_locked to our peer for channel {}", log_bytes!(self.channel_id));
4095                         return Ok((Some(funding_locked), timed_out_htlcs));
4096                 }
4097
4098                 let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
4099                 if non_shutdown_state >= ChannelState::ChannelFunded as u32 ||
4100                    (non_shutdown_state & ChannelState::OurFundingLocked as u32) == ChannelState::OurFundingLocked as u32 {
4101                         let mut funding_tx_confirmations = height as i64 - self.funding_tx_confirmation_height as i64 + 1;
4102                         if self.funding_tx_confirmation_height == 0 {
4103                                 // Note that check_get_funding_locked may reset funding_tx_confirmation_height to
4104                                 // zero if it has been reorged out, however in either case, our state flags
4105                                 // indicate we've already sent a funding_locked
4106                                 funding_tx_confirmations = 0;
4107                         }
4108
4109                         // If we've sent funding_locked (or have both sent and received funding_locked), and
4110                         // the funding transaction's confirmation count has dipped below minimum_depth / 2,
4111                         // close the channel and hope we can get the latest state on chain (because presumably
4112                         // the funding transaction is at least still in the mempool of most nodes).
4113                         if funding_tx_confirmations < self.minimum_depth.unwrap() as i64 / 2 {
4114                                 return Err(msgs::ErrorMessage {
4115                                         channel_id: self.channel_id(),
4116                                         data: format!("Funding transaction was un-confirmed. Locked at {} confs, now have {} confs.", self.minimum_depth.unwrap(), funding_tx_confirmations),
4117                                 });
4118                         }
4119                 }
4120
4121                 Ok((None, timed_out_htlcs))
4122         }
4123
4124         /// Indicates the funding transaction is no longer confirmed in the main chain. This may
4125         /// force-close the channel, but may also indicate a harmless reorganization of a block or two
4126         /// before the channel has reached funding_locked and we can just wait for more blocks.
4127         pub fn funding_transaction_unconfirmed<L: Deref>(&mut self, logger: &L) -> Result<(), msgs::ErrorMessage> where L::Target: Logger {
4128                 if self.funding_tx_confirmation_height != 0 {
4129                         // We handle the funding disconnection by calling best_block_updated with a height one
4130                         // below where our funding was connected, implying a reorg back to conf_height - 1.
4131                         let reorg_height = self.funding_tx_confirmation_height - 1;
4132                         // We use the time field to bump the current time we set on channel updates if its
4133                         // larger. If we don't know that time has moved forward, we can just set it to the last
4134                         // time we saw and it will be ignored.
4135                         let best_time = self.update_time_counter;
4136                         match self.best_block_updated(reorg_height, best_time, logger) {
4137                                 Ok((funding_locked, timed_out_htlcs)) => {
4138                                         assert!(funding_locked.is_none(), "We can't generate a funding with 0 confirmations?");
4139                                         assert!(timed_out_htlcs.is_empty(), "We can't have accepted HTLCs with a timeout before our funding confirmation?");
4140                                         Ok(())
4141                                 },
4142                                 Err(e) => Err(e)
4143                         }
4144                 } else {
4145                         // We never learned about the funding confirmation anyway, just ignore
4146                         Ok(())
4147                 }
4148         }
4149
4150         // Methods to get unprompted messages to send to the remote end (or where we already returned
4151         // something in the handler for the message that prompted this message):
4152
4153         pub fn get_open_channel(&self, chain_hash: BlockHash) -> msgs::OpenChannel {
4154                 if !self.is_outbound() {
4155                         panic!("Tried to open a channel for an inbound channel?");
4156                 }
4157                 if self.channel_state != ChannelState::OurInitSent as u32 {
4158                         panic!("Cannot generate an open_channel after we've moved forward");
4159                 }
4160
4161                 if self.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
4162                         panic!("Tried to send an open_channel for a channel that has already advanced");
4163                 }
4164
4165                 let first_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
4166                 let keys = self.get_holder_pubkeys();
4167
4168                 msgs::OpenChannel {
4169                         chain_hash,
4170                         temporary_channel_id: self.channel_id,
4171                         funding_satoshis: self.channel_value_satoshis,
4172                         push_msat: self.channel_value_satoshis * 1000 - self.value_to_self_msat,
4173                         dust_limit_satoshis: self.holder_dust_limit_satoshis,
4174                         max_htlc_value_in_flight_msat: Channel::<Signer>::get_holder_max_htlc_value_in_flight_msat(self.channel_value_satoshis),
4175                         channel_reserve_satoshis: Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis),
4176                         htlc_minimum_msat: self.holder_htlc_minimum_msat,
4177                         feerate_per_kw: self.feerate_per_kw as u32,
4178                         to_self_delay: self.get_holder_selected_contest_delay(),
4179                         max_accepted_htlcs: OUR_MAX_HTLCS,
4180                         funding_pubkey: keys.funding_pubkey,
4181                         revocation_basepoint: keys.revocation_basepoint,
4182                         payment_point: keys.payment_point,
4183                         delayed_payment_basepoint: keys.delayed_payment_basepoint,
4184                         htlc_basepoint: keys.htlc_basepoint,
4185                         first_per_commitment_point,
4186                         channel_flags: if self.config.announced_channel {1} else {0},
4187                         shutdown_scriptpubkey: OptionalField::Present(match &self.shutdown_scriptpubkey {
4188                                 Some(script) => script.clone().into_inner(),
4189                                 None => Builder::new().into_script(),
4190                         }),
4191                 }
4192         }
4193
4194         pub fn get_accept_channel(&self) -> msgs::AcceptChannel {
4195                 if self.is_outbound() {
4196                         panic!("Tried to send accept_channel for an outbound channel?");
4197                 }
4198                 if self.channel_state != (ChannelState::OurInitSent as u32) | (ChannelState::TheirInitSent as u32) {
4199                         panic!("Tried to send accept_channel after channel had moved forward");
4200                 }
4201                 if self.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
4202                         panic!("Tried to send an accept_channel for a channel that has already advanced");
4203                 }
4204
4205                 let first_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
4206                 let keys = self.get_holder_pubkeys();
4207
4208                 msgs::AcceptChannel {
4209                         temporary_channel_id: self.channel_id,
4210                         dust_limit_satoshis: self.holder_dust_limit_satoshis,
4211                         max_htlc_value_in_flight_msat: Channel::<Signer>::get_holder_max_htlc_value_in_flight_msat(self.channel_value_satoshis),
4212                         channel_reserve_satoshis: Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis),
4213                         htlc_minimum_msat: self.holder_htlc_minimum_msat,
4214                         minimum_depth: self.minimum_depth.unwrap(),
4215                         to_self_delay: self.get_holder_selected_contest_delay(),
4216                         max_accepted_htlcs: OUR_MAX_HTLCS,
4217                         funding_pubkey: keys.funding_pubkey,
4218                         revocation_basepoint: keys.revocation_basepoint,
4219                         payment_point: keys.payment_point,
4220                         delayed_payment_basepoint: keys.delayed_payment_basepoint,
4221                         htlc_basepoint: keys.htlc_basepoint,
4222                         first_per_commitment_point,
4223                         shutdown_scriptpubkey: OptionalField::Present(match &self.shutdown_scriptpubkey {
4224                                 Some(script) => script.clone().into_inner(),
4225                                 None => Builder::new().into_script(),
4226                         }),
4227                 }
4228         }
4229
4230         /// If an Err is returned, it is a ChannelError::Close (for get_outbound_funding_created)
4231         fn get_outbound_funding_created_signature<L: Deref>(&mut self, logger: &L) -> Result<Signature, ChannelError> where L::Target: Logger {
4232                 let counterparty_keys = self.build_remote_transaction_keys()?;
4233                 let counterparty_initial_commitment_tx = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, false, logger).0;
4234                 Ok(self.holder_signer.sign_counterparty_commitment(&counterparty_initial_commitment_tx, &self.secp_ctx)
4235                                 .map_err(|_| ChannelError::Close("Failed to get signatures for new commitment_signed".to_owned()))?.0)
4236         }
4237
4238         /// Updates channel state with knowledge of the funding transaction's txid/index, and generates
4239         /// a funding_created message for the remote peer.
4240         /// Panics if called at some time other than immediately after initial handshake, if called twice,
4241         /// or if called on an inbound channel.
4242         /// Note that channel_id changes during this call!
4243         /// Do NOT broadcast the funding transaction until after a successful funding_signed call!
4244         /// If an Err is returned, it is a ChannelError::Close.
4245         pub fn get_outbound_funding_created<L: Deref>(&mut self, funding_transaction: Transaction, funding_txo: OutPoint, logger: &L) -> Result<msgs::FundingCreated, ChannelError> where L::Target: Logger {
4246                 if !self.is_outbound() {
4247                         panic!("Tried to create outbound funding_created message on an inbound channel!");
4248                 }
4249                 if self.channel_state != (ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32) {
4250                         panic!("Tried to get a funding_created messsage at a time other than immediately after initial handshake completion (or tried to get funding_created twice)");
4251                 }
4252                 if self.commitment_secrets.get_min_seen_secret() != (1 << 48) ||
4253                                 self.cur_counterparty_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER ||
4254                                 self.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
4255                         panic!("Should not have advanced channel commitment tx numbers prior to funding_created");
4256                 }
4257
4258                 self.channel_transaction_parameters.funding_outpoint = Some(funding_txo);
4259                 self.holder_signer.ready_channel(&self.channel_transaction_parameters);
4260
4261                 let signature = match self.get_outbound_funding_created_signature(logger) {
4262                         Ok(res) => res,
4263                         Err(e) => {
4264                                 log_error!(logger, "Got bad signatures: {:?}!", e);
4265                                 self.channel_transaction_parameters.funding_outpoint = None;
4266                                 return Err(e);
4267                         }
4268                 };
4269
4270                 let temporary_channel_id = self.channel_id;
4271
4272                 // Now that we're past error-generating stuff, update our local state:
4273
4274                 self.channel_state = ChannelState::FundingCreated as u32;
4275                 self.channel_id = funding_txo.to_channel_id();
4276                 self.funding_transaction = Some(funding_transaction);
4277
4278                 Ok(msgs::FundingCreated {
4279                         temporary_channel_id,
4280                         funding_txid: funding_txo.txid,
4281                         funding_output_index: funding_txo.index,
4282                         signature
4283                 })
4284         }
4285
4286         /// Gets an UnsignedChannelAnnouncement, as well as a signature covering it using our
4287         /// bitcoin_key, if available, for this channel. The channel must be publicly announceable and
4288         /// available for use (have exchanged FundingLocked messages in both directions). Should be used
4289         /// for both loose and in response to an AnnouncementSignatures message from the remote peer.
4290         /// Will only fail if we're not in a state where channel_announcement may be sent (including
4291         /// closing).
4292         /// Note that the "channel must be funded" requirement is stricter than BOLT 7 requires - see
4293         /// https://github.com/lightningnetwork/lightning-rfc/issues/468
4294         ///
4295         /// This will only return ChannelError::Ignore upon failure.
4296         pub fn get_channel_announcement(&self, node_id: PublicKey, chain_hash: BlockHash) -> Result<(msgs::UnsignedChannelAnnouncement, Signature), ChannelError> {
4297                 if !self.config.announced_channel {
4298                         return Err(ChannelError::Ignore("Channel is not available for public announcements".to_owned()));
4299                 }
4300                 if self.channel_state & (ChannelState::ChannelFunded as u32) == 0 {
4301                         return Err(ChannelError::Ignore("Cannot get a ChannelAnnouncement until the channel funding has been locked".to_owned()));
4302                 }
4303                 if (self.channel_state & (ChannelState::LocalShutdownSent as u32 | ChannelState::ShutdownComplete as u32)) != 0 {
4304                         return Err(ChannelError::Ignore("Cannot get a ChannelAnnouncement once the channel is closing".to_owned()));
4305                 }
4306
4307                 let were_node_one = node_id.serialize()[..] < self.counterparty_node_id.serialize()[..];
4308
4309                 let msg = msgs::UnsignedChannelAnnouncement {
4310                         features: ChannelFeatures::known(),
4311                         chain_hash,
4312                         short_channel_id: self.get_short_channel_id().unwrap(),
4313                         node_id_1: if were_node_one { node_id } else { self.get_counterparty_node_id() },
4314                         node_id_2: if were_node_one { self.get_counterparty_node_id() } else { node_id },
4315                         bitcoin_key_1: if were_node_one { self.get_holder_pubkeys().funding_pubkey } else { self.counterparty_funding_pubkey().clone() },
4316                         bitcoin_key_2: if were_node_one { self.counterparty_funding_pubkey().clone() } else { self.get_holder_pubkeys().funding_pubkey },
4317                         excess_data: Vec::new(),
4318                 };
4319
4320                 let sig = self.holder_signer.sign_channel_announcement(&msg, &self.secp_ctx)
4321                         .map_err(|_| ChannelError::Ignore("Signer rejected channel_announcement".to_owned()))?;
4322
4323                 Ok((msg, sig))
4324         }
4325
4326         /// Signs the given channel announcement, returning a ChannelError::Ignore if no keys are
4327         /// available.
4328         fn sign_channel_announcement(&self, our_node_secret: &SecretKey, our_node_id: PublicKey, msghash: secp256k1::Message, announcement: msgs::UnsignedChannelAnnouncement, our_bitcoin_sig: Signature) -> Result<msgs::ChannelAnnouncement, ChannelError> {
4329                 if let Some((their_node_sig, their_bitcoin_sig)) = self.announcement_sigs {
4330                         let were_node_one = announcement.node_id_1 == our_node_id;
4331
4332                         let our_node_sig = self.secp_ctx.sign(&msghash, our_node_secret);
4333                         Ok(msgs::ChannelAnnouncement {
4334                                 node_signature_1: if were_node_one { our_node_sig } else { their_node_sig },
4335                                 node_signature_2: if were_node_one { their_node_sig } else { our_node_sig },
4336                                 bitcoin_signature_1: if were_node_one { our_bitcoin_sig } else { their_bitcoin_sig },
4337                                 bitcoin_signature_2: if were_node_one { their_bitcoin_sig } else { our_bitcoin_sig },
4338                                 contents: announcement,
4339                         })
4340                 } else {
4341                         Err(ChannelError::Ignore("Attempted to sign channel announcement before we'd received announcement_signatures".to_string()))
4342                 }
4343         }
4344
4345         /// Processes an incoming announcement_signatures message, providing a fully-signed
4346         /// channel_announcement message which we can broadcast and storing our counterparty's
4347         /// signatures for later reconstruction/rebroadcast of the channel_announcement.
4348         pub fn announcement_signatures(&mut self, our_node_secret: &SecretKey, our_node_id: PublicKey, chain_hash: BlockHash, msg: &msgs::AnnouncementSignatures) -> Result<msgs::ChannelAnnouncement, ChannelError> {
4349                 let (announcement, our_bitcoin_sig) = self.get_channel_announcement(our_node_id.clone(), chain_hash)?;
4350
4351                 let msghash = hash_to_message!(&Sha256d::hash(&announcement.encode()[..])[..]);
4352
4353                 if self.secp_ctx.verify(&msghash, &msg.node_signature, &self.get_counterparty_node_id()).is_err() {
4354                         return Err(ChannelError::Close(format!(
4355                                 "Bad announcement_signatures. Failed to verify node_signature. UnsignedChannelAnnouncement used for verification is {:?}. their_node_key is {:?}",
4356                                  &announcement, self.get_counterparty_node_id())));
4357                 }
4358                 if self.secp_ctx.verify(&msghash, &msg.bitcoin_signature, self.counterparty_funding_pubkey()).is_err() {
4359                         return Err(ChannelError::Close(format!(
4360                                 "Bad announcement_signatures. Failed to verify bitcoin_signature. UnsignedChannelAnnouncement used for verification is {:?}. their_bitcoin_key is ({:?})",
4361                                 &announcement, self.counterparty_funding_pubkey())));
4362                 }
4363
4364                 self.announcement_sigs = Some((msg.node_signature, msg.bitcoin_signature));
4365
4366                 self.sign_channel_announcement(our_node_secret, our_node_id, msghash, announcement, our_bitcoin_sig)
4367         }
4368
4369         /// Gets a signed channel_announcement for this channel, if we previously received an
4370         /// announcement_signatures from our counterparty.
4371         pub fn get_signed_channel_announcement(&self, our_node_secret: &SecretKey, our_node_id: PublicKey, chain_hash: BlockHash) -> Option<msgs::ChannelAnnouncement> {
4372                 let (announcement, our_bitcoin_sig) = match self.get_channel_announcement(our_node_id.clone(), chain_hash) {
4373                         Ok(res) => res,
4374                         Err(_) => return None,
4375                 };
4376                 let msghash = hash_to_message!(&Sha256d::hash(&announcement.encode()[..])[..]);
4377                 match self.sign_channel_announcement(our_node_secret, our_node_id, msghash, announcement, our_bitcoin_sig) {
4378                         Ok(res) => Some(res),
4379                         Err(_) => None,
4380                 }
4381         }
4382
4383         /// May panic if called on a channel that wasn't immediately-previously
4384         /// self.remove_uncommitted_htlcs_and_mark_paused()'d
4385         pub fn get_channel_reestablish<L: Deref>(&self, logger: &L) -> msgs::ChannelReestablish where L::Target: Logger {
4386                 assert_eq!(self.channel_state & ChannelState::PeerDisconnected as u32, ChannelState::PeerDisconnected as u32);
4387                 assert_ne!(self.cur_counterparty_commitment_transaction_number, INITIAL_COMMITMENT_NUMBER);
4388                 // Prior to static_remotekey, my_current_per_commitment_point was critical to claiming
4389                 // current to_remote balances. However, it no longer has any use, and thus is now simply
4390                 // set to a dummy (but valid, as required by the spec) public key.
4391                 // fuzztarget mode marks a subset of pubkeys as invalid so that we can hit "invalid pubkey"
4392                 // branches, but we unwrap it below, so we arbitrarily select a dummy pubkey which is both
4393                 // valid, and valid in fuzztarget mode's arbitrary validity criteria:
4394                 let mut pk = [2; 33]; pk[1] = 0xff;
4395                 let dummy_pubkey = PublicKey::from_slice(&pk).unwrap();
4396                 let data_loss_protect = if self.cur_counterparty_commitment_transaction_number + 1 < INITIAL_COMMITMENT_NUMBER {
4397                         let remote_last_secret = self.commitment_secrets.get_secret(self.cur_counterparty_commitment_transaction_number + 2).unwrap();
4398                         log_trace!(logger, "Enough info to generate a Data Loss Protect with per_commitment_secret {} for channel {}", log_bytes!(remote_last_secret), log_bytes!(self.channel_id()));
4399                         OptionalField::Present(DataLossProtect {
4400                                 your_last_per_commitment_secret: remote_last_secret,
4401                                 my_current_per_commitment_point: dummy_pubkey
4402                         })
4403                 } else {
4404                         log_info!(logger, "Sending a data_loss_protect with no previous remote per_commitment_secret for channel {}", log_bytes!(self.channel_id()));
4405                         OptionalField::Present(DataLossProtect {
4406                                 your_last_per_commitment_secret: [0;32],
4407                                 my_current_per_commitment_point: dummy_pubkey,
4408                         })
4409                 };
4410                 msgs::ChannelReestablish {
4411                         channel_id: self.channel_id(),
4412                         // The protocol has two different commitment number concepts - the "commitment
4413                         // transaction number", which starts from 0 and counts up, and the "revocation key
4414                         // index" which starts at INITIAL_COMMITMENT_NUMBER and counts down. We track
4415                         // commitment transaction numbers by the index which will be used to reveal the
4416                         // revocation key for that commitment transaction, which means we have to convert them
4417                         // to protocol-level commitment numbers here...
4418
4419                         // next_local_commitment_number is the next commitment_signed number we expect to
4420                         // receive (indicating if they need to resend one that we missed).
4421                         next_local_commitment_number: INITIAL_COMMITMENT_NUMBER - self.cur_holder_commitment_transaction_number,
4422                         // We have to set next_remote_commitment_number to the next revoke_and_ack we expect to
4423                         // receive, however we track it by the next commitment number for a remote transaction
4424                         // (which is one further, as they always revoke previous commitment transaction, not
4425                         // the one we send) so we have to decrement by 1. Note that if
4426                         // cur_counterparty_commitment_transaction_number is INITIAL_COMMITMENT_NUMBER we will have
4427                         // dropped this channel on disconnect as it hasn't yet reached FundingSent so we can't
4428                         // overflow here.
4429                         next_remote_commitment_number: INITIAL_COMMITMENT_NUMBER - self.cur_counterparty_commitment_transaction_number - 1,
4430                         data_loss_protect,
4431                 }
4432         }
4433
4434
4435         // Send stuff to our remote peers:
4436
4437         /// Adds a pending outbound HTLC to this channel, note that you probably want
4438         /// send_htlc_and_commit instead cause you'll want both messages at once.
4439         ///
4440         /// This returns an optional UpdateAddHTLC as we may be in a state where we cannot add HTLCs on
4441         /// the wire:
4442         /// * In cases where we're waiting on the remote peer to send us a revoke_and_ack, we
4443         ///   wouldn't be able to determine what they actually ACK'ed if we have two sets of updates
4444         ///   awaiting ACK.
4445         /// * In cases where we're marked MonitorUpdateFailed, we cannot commit to a new state as we
4446         ///   may not yet have sent the previous commitment update messages and will need to regenerate
4447         ///   them.
4448         ///
4449         /// You MUST call send_commitment prior to calling any other methods on this Channel!
4450         ///
4451         /// If an Err is returned, it's a ChannelError::Ignore!
4452         pub fn send_htlc(&mut self, amount_msat: u64, payment_hash: PaymentHash, cltv_expiry: u32, source: HTLCSource, onion_routing_packet: msgs::OnionPacket) -> Result<Option<msgs::UpdateAddHTLC>, ChannelError> {
4453                 if (self.channel_state & (ChannelState::ChannelFunded as u32 | BOTH_SIDES_SHUTDOWN_MASK)) != (ChannelState::ChannelFunded as u32) {
4454                         return Err(ChannelError::Ignore("Cannot send HTLC until channel is fully established and we haven't started shutting down".to_owned()));
4455                 }
4456                 let channel_total_msat = self.channel_value_satoshis * 1000;
4457                 if amount_msat > channel_total_msat {
4458                         return Err(ChannelError::Ignore(format!("Cannot send amount {}, because it is more than the total value of the channel {}", amount_msat, channel_total_msat)));
4459                 }
4460
4461                 if amount_msat == 0 {
4462                         return Err(ChannelError::Ignore("Cannot send 0-msat HTLC".to_owned()));
4463                 }
4464
4465                 if amount_msat < self.counterparty_htlc_minimum_msat {
4466                         return Err(ChannelError::Ignore(format!("Cannot send less than their minimum HTLC value ({})", self.counterparty_htlc_minimum_msat)));
4467                 }
4468
4469                 if (self.channel_state & (ChannelState::PeerDisconnected as u32)) != 0 {
4470                         // Note that this should never really happen, if we're !is_live() on receipt of an
4471                         // incoming HTLC for relay will result in us rejecting the HTLC and we won't allow
4472                         // the user to send directly into a !is_live() channel. However, if we
4473                         // disconnected during the time the previous hop was doing the commitment dance we may
4474                         // end up getting here after the forwarding delay. In any case, returning an
4475                         // IgnoreError will get ChannelManager to do the right thing and fail backwards now.
4476                         return Err(ChannelError::Ignore("Cannot send an HTLC while disconnected from channel counterparty".to_owned()));
4477                 }
4478
4479                 let inbound_stats = self.get_inbound_pending_htlc_stats();
4480                 let outbound_stats = self.get_outbound_pending_htlc_stats();
4481                 if outbound_stats.pending_htlcs + 1 > self.counterparty_max_accepted_htlcs as u32 {
4482                         return Err(ChannelError::Ignore(format!("Cannot push more than their max accepted HTLCs ({})", self.counterparty_max_accepted_htlcs)));
4483                 }
4484                 // Check their_max_htlc_value_in_flight_msat
4485                 if outbound_stats.pending_htlcs_value_msat + amount_msat > self.counterparty_max_htlc_value_in_flight_msat {
4486                         return Err(ChannelError::Ignore(format!("Cannot send value that would put us over the max HTLC value in flight our peer will accept ({})", self.counterparty_max_htlc_value_in_flight_msat)));
4487                 }
4488
4489                 if !self.is_outbound() {
4490                         // Check that we won't violate the remote channel reserve by adding this HTLC.
4491                         let counterparty_balance_msat = self.channel_value_satoshis * 1000 - self.value_to_self_msat;
4492                         let holder_selected_chan_reserve_msat = Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis) * 1000;
4493                         let htlc_candidate = HTLCCandidate::new(amount_msat, HTLCInitiator::LocalOffered);
4494                         let counterparty_commit_tx_fee_msat = self.next_remote_commit_tx_fee_msat(htlc_candidate, None);
4495                         if counterparty_balance_msat < holder_selected_chan_reserve_msat + counterparty_commit_tx_fee_msat {
4496                                 return Err(ChannelError::Ignore("Cannot send value that would put counterparty balance under holder-announced channel reserve value".to_owned()));
4497                         }
4498                 }
4499
4500                 let exposure_dust_limit_success_sats = (self.get_dust_buffer_feerate() as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) + self.counterparty_dust_limit_satoshis;
4501                 if amount_msat / 1000 < exposure_dust_limit_success_sats {
4502                         let on_counterparty_dust_htlc_exposure_msat = inbound_stats.on_counterparty_tx_dust_exposure_msat + outbound_stats.on_counterparty_tx_dust_exposure_msat + amount_msat;
4503                         if on_counterparty_dust_htlc_exposure_msat > self.get_max_dust_htlc_exposure_msat() {
4504                                 return Err(ChannelError::Ignore(format!("Cannot send value that would put our exposure to dust HTLCs at {} over the limit {} on counterparty commitment tx",
4505                                         on_counterparty_dust_htlc_exposure_msat, self.get_max_dust_htlc_exposure_msat())));
4506                         }
4507                 }
4508
4509                 let exposure_dust_limit_timeout_sats = (self.get_dust_buffer_feerate() as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + self.holder_dust_limit_satoshis;
4510                 if amount_msat / 1000 <  exposure_dust_limit_timeout_sats {
4511                         let on_holder_dust_htlc_exposure_msat = inbound_stats.on_holder_tx_dust_exposure_msat + outbound_stats.on_holder_tx_dust_exposure_msat + amount_msat;
4512                         if on_holder_dust_htlc_exposure_msat > self.get_max_dust_htlc_exposure_msat() {
4513                                 return Err(ChannelError::Ignore(format!("Cannot send value that would put our exposure to dust HTLCs at {} over the limit {} on holder commitment tx",
4514                                         on_holder_dust_htlc_exposure_msat, self.get_max_dust_htlc_exposure_msat())));
4515                         }
4516                 }
4517
4518                 let pending_value_to_self_msat = self.value_to_self_msat - outbound_stats.pending_htlcs_value_msat;
4519                 if pending_value_to_self_msat < amount_msat {
4520                         return Err(ChannelError::Ignore(format!("Cannot send value that would overdraw remaining funds. Amount: {}, pending value to self {}", amount_msat, pending_value_to_self_msat)));
4521                 }
4522
4523                 // `2 *` and extra HTLC are for the fee spike buffer.
4524                 let commit_tx_fee_msat = if self.is_outbound() {
4525                         let htlc_candidate = HTLCCandidate::new(amount_msat, HTLCInitiator::LocalOffered);
4526                         FEE_SPIKE_BUFFER_FEE_INCREASE_MULTIPLE * self.next_local_commit_tx_fee_msat(htlc_candidate, Some(()))
4527                 } else { 0 };
4528                 if pending_value_to_self_msat - amount_msat < commit_tx_fee_msat {
4529                         return Err(ChannelError::Ignore(format!("Cannot send value that would not leave enough to pay for fees. Pending value to self: {}. local_commit_tx_fee {}", pending_value_to_self_msat, commit_tx_fee_msat)));
4530                 }
4531
4532                 // Check self.counterparty_selected_channel_reserve_satoshis (the amount we must keep as
4533                 // reserve for the remote to have something to claim if we misbehave)
4534                 let chan_reserve_msat = self.counterparty_selected_channel_reserve_satoshis.unwrap() * 1000;
4535                 if pending_value_to_self_msat - amount_msat - commit_tx_fee_msat < chan_reserve_msat {
4536                         return Err(ChannelError::Ignore(format!("Cannot send value that would put our balance under counterparty-announced channel reserve value ({})", chan_reserve_msat)));
4537                 }
4538
4539                 // Now update local state:
4540                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::MonitorUpdateFailed as u32)) != 0 {
4541                         self.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::AddHTLC {
4542                                 amount_msat,
4543                                 payment_hash,
4544                                 cltv_expiry,
4545                                 source,
4546                                 onion_routing_packet,
4547                         });
4548                         return Ok(None);
4549                 }
4550
4551                 self.pending_outbound_htlcs.push(OutboundHTLCOutput {
4552                         htlc_id: self.next_holder_htlc_id,
4553                         amount_msat,
4554                         payment_hash: payment_hash.clone(),
4555                         cltv_expiry,
4556                         state: OutboundHTLCState::LocalAnnounced(Box::new(onion_routing_packet.clone())),
4557                         source,
4558                 });
4559
4560                 let res = msgs::UpdateAddHTLC {
4561                         channel_id: self.channel_id,
4562                         htlc_id: self.next_holder_htlc_id,
4563                         amount_msat,
4564                         payment_hash,
4565                         cltv_expiry,
4566                         onion_routing_packet,
4567                 };
4568                 self.next_holder_htlc_id += 1;
4569
4570                 Ok(Some(res))
4571         }
4572
4573         /// Creates a signed commitment transaction to send to the remote peer.
4574         /// Always returns a ChannelError::Close if an immediately-preceding (read: the
4575         /// last call to this Channel) send_htlc returned Ok(Some(_)) and there is an Err.
4576         /// May panic if called except immediately after a successful, Ok(Some(_))-returning send_htlc.
4577         pub fn send_commitment<L: Deref>(&mut self, logger: &L) -> Result<(msgs::CommitmentSigned, ChannelMonitorUpdate), ChannelError> where L::Target: Logger {
4578                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
4579                         panic!("Cannot create commitment tx until channel is fully established");
4580                 }
4581                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == (ChannelState::AwaitingRemoteRevoke as u32) {
4582                         panic!("Cannot create commitment tx until remote revokes their previous commitment");
4583                 }
4584                 if (self.channel_state & (ChannelState::PeerDisconnected as u32)) == (ChannelState::PeerDisconnected as u32) {
4585                         panic!("Cannot create commitment tx while disconnected, as send_htlc will have returned an Err so a send_commitment precondition has been violated");
4586                 }
4587                 if (self.channel_state & (ChannelState::MonitorUpdateFailed as u32)) == (ChannelState::MonitorUpdateFailed as u32) {
4588                         panic!("Cannot create commitment tx while awaiting monitor update unfreeze, as send_htlc will have returned an Err so a send_commitment precondition has been violated");
4589                 }
4590                 let mut have_updates = self.is_outbound() && self.pending_update_fee.is_some();
4591                 for htlc in self.pending_outbound_htlcs.iter() {
4592                         if let OutboundHTLCState::LocalAnnounced(_) = htlc.state {
4593                                 have_updates = true;
4594                         }
4595                         if have_updates { break; }
4596                 }
4597                 for htlc in self.pending_inbound_htlcs.iter() {
4598                         if let InboundHTLCState::LocalRemoved(_) = htlc.state {
4599                                 have_updates = true;
4600                         }
4601                         if have_updates { break; }
4602                 }
4603                 if !have_updates {
4604                         panic!("Cannot create commitment tx until we have some updates to send");
4605                 }
4606                 self.send_commitment_no_status_check(logger)
4607         }
4608         /// Only fails in case of bad keys
4609         fn send_commitment_no_status_check<L: Deref>(&mut self, logger: &L) -> Result<(msgs::CommitmentSigned, ChannelMonitorUpdate), ChannelError> where L::Target: Logger {
4610                 log_trace!(logger, "Updating HTLC state for a newly-sent commitment_signed...");
4611                 // We can upgrade the status of some HTLCs that are waiting on a commitment, even if we
4612                 // fail to generate this, we still are at least at a position where upgrading their status
4613                 // is acceptable.
4614                 for htlc in self.pending_inbound_htlcs.iter_mut() {
4615                         let new_state = if let &InboundHTLCState::AwaitingRemoteRevokeToAnnounce(ref forward_info) = &htlc.state {
4616                                 Some(InboundHTLCState::AwaitingAnnouncedRemoteRevoke(forward_info.clone()))
4617                         } else { None };
4618                         if let Some(state) = new_state {
4619                                 log_trace!(logger, " ...promoting inbound AwaitingRemoteRevokeToAnnounce {} to AwaitingAnnouncedRemoteRevoke", log_bytes!(htlc.payment_hash.0));
4620                                 htlc.state = state;
4621                         }
4622                 }
4623                 for htlc in self.pending_outbound_htlcs.iter_mut() {
4624                         if let Some(fail_reason) = if let &mut OutboundHTLCState::AwaitingRemoteRevokeToRemove(ref mut fail_reason) = &mut htlc.state {
4625                                 Some(fail_reason.take())
4626                         } else { None } {
4627                                 log_trace!(logger, " ...promoting outbound AwaitingRemoteRevokeToRemove {} to AwaitingRemovedRemoteRevoke", log_bytes!(htlc.payment_hash.0));
4628                                 htlc.state = OutboundHTLCState::AwaitingRemovedRemoteRevoke(fail_reason);
4629                         }
4630                 }
4631                 if let Some((feerate, update_state)) = self.pending_update_fee {
4632                         if update_state == FeeUpdateState::AwaitingRemoteRevokeToAnnounce {
4633                                 debug_assert!(!self.is_outbound());
4634                                 log_trace!(logger, " ...promoting inbound AwaitingRemoteRevokeToAnnounce fee update {} to Committed", feerate);
4635                                 self.feerate_per_kw = feerate;
4636                                 self.pending_update_fee = None;
4637                         }
4638                 }
4639                 self.resend_order = RAACommitmentOrder::RevokeAndACKFirst;
4640
4641                 let (res, counterparty_commitment_txid, htlcs) = match self.send_commitment_no_state_update(logger) {
4642                         Ok((res, (counterparty_commitment_tx, mut htlcs))) => {
4643                                 // Update state now that we've passed all the can-fail calls...
4644                                 let htlcs_no_ref: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)> =
4645                                         htlcs.drain(..).map(|(htlc, htlc_source)| (htlc, htlc_source.map(|source_ref| Box::new(source_ref.clone())))).collect();
4646                                 (res, counterparty_commitment_tx, htlcs_no_ref)
4647                         },
4648                         Err(e) => return Err(e),
4649                 };
4650
4651                 self.latest_monitor_update_id += 1;
4652                 let monitor_update = ChannelMonitorUpdate {
4653                         update_id: self.latest_monitor_update_id,
4654                         updates: vec![ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo {
4655                                 commitment_txid: counterparty_commitment_txid,
4656                                 htlc_outputs: htlcs.clone(),
4657                                 commitment_number: self.cur_counterparty_commitment_transaction_number,
4658                                 their_revocation_point: self.counterparty_cur_commitment_point.unwrap()
4659                         }]
4660                 };
4661                 self.channel_state |= ChannelState::AwaitingRemoteRevoke as u32;
4662                 Ok((res, monitor_update))
4663         }
4664
4665         /// Only fails in case of bad keys. Used for channel_reestablish commitment_signed generation
4666         /// when we shouldn't change HTLC/channel state.
4667         fn send_commitment_no_state_update<L: Deref>(&self, logger: &L) -> Result<(msgs::CommitmentSigned, (Txid, Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)>)), ChannelError> where L::Target: Logger {
4668                 let counterparty_keys = self.build_remote_transaction_keys()?;
4669                 let counterparty_commitment_tx = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, true, logger);
4670                 let feerate_per_kw = counterparty_commitment_tx.1;
4671                 let counterparty_commitment_txid = counterparty_commitment_tx.0.trust().txid();
4672                 let (signature, htlc_signatures);
4673
4674                 #[cfg(any(test, feature = "fuzztarget"))]
4675                 {
4676                         if !self.is_outbound() {
4677                                 let projected_commit_tx_info = self.next_remote_commitment_tx_fee_info_cached.lock().unwrap().take();
4678                                 *self.next_local_commitment_tx_fee_info_cached.lock().unwrap() = None;
4679                                 if let Some(info) = projected_commit_tx_info {
4680                                         let total_pending_htlcs = self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len();
4681                                         if info.total_pending_htlcs == total_pending_htlcs
4682                                                 && info.next_holder_htlc_id == self.next_holder_htlc_id
4683                                                 && info.next_counterparty_htlc_id == self.next_counterparty_htlc_id
4684                                                 && info.feerate == self.feerate_per_kw {
4685                                                         let actual_fee = self.commit_tx_fee_msat(counterparty_commitment_tx.2);
4686                                                         assert_eq!(actual_fee, info.fee);
4687                                                 }
4688                                 }
4689                         }
4690                 }
4691
4692                 {
4693                         let mut htlcs = Vec::with_capacity(counterparty_commitment_tx.3.len());
4694                         for &(ref htlc, _) in counterparty_commitment_tx.3.iter() {
4695                                 htlcs.push(htlc);
4696                         }
4697
4698                         let res = self.holder_signer.sign_counterparty_commitment(&counterparty_commitment_tx.0, &self.secp_ctx)
4699                                 .map_err(|_| ChannelError::Close("Failed to get signatures for new commitment_signed".to_owned()))?;
4700                         signature = res.0;
4701                         htlc_signatures = res.1;
4702
4703                         log_trace!(logger, "Signed remote commitment tx {} (txid {}) with redeemscript {} -> {} in channel {}",
4704                                 encode::serialize_hex(&counterparty_commitment_tx.0.trust().built_transaction().transaction),
4705                                 &counterparty_commitment_txid, encode::serialize_hex(&self.get_funding_redeemscript()),
4706                                 log_bytes!(signature.serialize_compact()[..]), log_bytes!(self.channel_id()));
4707
4708                         for (ref htlc_sig, ref htlc) in htlc_signatures.iter().zip(htlcs) {
4709                                 log_trace!(logger, "Signed remote HTLC tx {} with redeemscript {} with pubkey {} -> {} in channel {}",
4710                                         encode::serialize_hex(&chan_utils::build_htlc_transaction(&counterparty_commitment_txid, feerate_per_kw, self.get_holder_selected_contest_delay(), htlc, &counterparty_keys.broadcaster_delayed_payment_key, &counterparty_keys.revocation_key)),
4711                                         encode::serialize_hex(&chan_utils::get_htlc_redeemscript(&htlc, &counterparty_keys)),
4712                                         log_bytes!(counterparty_keys.broadcaster_htlc_key.serialize()),
4713                                         log_bytes!(htlc_sig.serialize_compact()[..]), log_bytes!(self.channel_id()));
4714                         }
4715                 }
4716
4717                 Ok((msgs::CommitmentSigned {
4718                         channel_id: self.channel_id,
4719                         signature,
4720                         htlc_signatures,
4721                 }, (counterparty_commitment_txid, counterparty_commitment_tx.3)))
4722         }
4723
4724         /// Adds a pending outbound HTLC to this channel, and creates a signed commitment transaction
4725         /// to send to the remote peer in one go.
4726         /// Shorthand for calling send_htlc() followed by send_commitment(), see docs on those for
4727         /// more info.
4728         pub fn send_htlc_and_commit<L: Deref>(&mut self, amount_msat: u64, payment_hash: PaymentHash, cltv_expiry: u32, source: HTLCSource, onion_routing_packet: msgs::OnionPacket, logger: &L) -> Result<Option<(msgs::UpdateAddHTLC, msgs::CommitmentSigned, ChannelMonitorUpdate)>, ChannelError> where L::Target: Logger {
4729                 match self.send_htlc(amount_msat, payment_hash, cltv_expiry, source, onion_routing_packet)? {
4730                         Some(update_add_htlc) => {
4731                                 let (commitment_signed, monitor_update) = self.send_commitment_no_status_check(logger)?;
4732                                 Ok(Some((update_add_htlc, commitment_signed, monitor_update)))
4733                         },
4734                         None => Ok(None)
4735                 }
4736         }
4737
4738         /// Get forwarding information for the counterparty.
4739         pub fn counterparty_forwarding_info(&self) -> Option<CounterpartyForwardingInfo> {
4740                 self.counterparty_forwarding_info.clone()
4741         }
4742
4743         pub fn channel_update(&mut self, msg: &msgs::ChannelUpdate) -> Result<(), ChannelError> {
4744                 if msg.contents.htlc_minimum_msat >= self.channel_value_satoshis * 1000 {
4745                         return Err(ChannelError::Close("Minimum htlc value is greater than channel value".to_string()));
4746                 }
4747                 self.counterparty_forwarding_info = Some(CounterpartyForwardingInfo {
4748                         fee_base_msat: msg.contents.fee_base_msat,
4749                         fee_proportional_millionths: msg.contents.fee_proportional_millionths,
4750                         cltv_expiry_delta: msg.contents.cltv_expiry_delta
4751                 });
4752
4753                 Ok(())
4754         }
4755
4756         /// Begins the shutdown process, getting a message for the remote peer and returning all
4757         /// holding cell HTLCs for payment failure.
4758         pub fn get_shutdown<K: Deref>(&mut self, keys_provider: &K, their_features: &InitFeatures, target_feerate_sats_per_kw: Option<u32>)
4759         -> Result<(msgs::Shutdown, Option<ChannelMonitorUpdate>, Vec<(HTLCSource, PaymentHash)>), APIError>
4760         where K::Target: KeysInterface<Signer = Signer> {
4761                 for htlc in self.pending_outbound_htlcs.iter() {
4762                         if let OutboundHTLCState::LocalAnnounced(_) = htlc.state {
4763                                 return Err(APIError::APIMisuseError{err: "Cannot begin shutdown with pending HTLCs. Process pending events first".to_owned()});
4764                         }
4765                 }
4766                 if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK != 0 {
4767                         if (self.channel_state & ChannelState::LocalShutdownSent as u32) == ChannelState::LocalShutdownSent as u32 {
4768                                 return Err(APIError::APIMisuseError{err: "Shutdown already in progress".to_owned()});
4769                         }
4770                         else if (self.channel_state & ChannelState::RemoteShutdownSent as u32) == ChannelState::RemoteShutdownSent as u32 {
4771                                 return Err(APIError::ChannelUnavailable{err: "Shutdown already in progress by remote".to_owned()});
4772                         }
4773                 }
4774                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
4775                 if self.channel_state & (ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32) != 0 {
4776                         return Err(APIError::ChannelUnavailable{err: "Cannot begin shutdown while peer is disconnected or we're waiting on a monitor update, maybe force-close instead?".to_owned()});
4777                 }
4778
4779                 let update_shutdown_script = match self.shutdown_scriptpubkey {
4780                         Some(_) => false,
4781                         None => {
4782                                 let shutdown_scriptpubkey = keys_provider.get_shutdown_scriptpubkey();
4783                                 if !shutdown_scriptpubkey.is_compatible(their_features) {
4784                                         return Err(APIError::IncompatibleShutdownScript { script: shutdown_scriptpubkey.clone() });
4785                                 }
4786                                 self.shutdown_scriptpubkey = Some(shutdown_scriptpubkey);
4787                                 true
4788                         },
4789                 };
4790
4791                 // From here on out, we may not fail!
4792                 self.target_closing_feerate_sats_per_kw = target_feerate_sats_per_kw;
4793                 if self.channel_state < ChannelState::FundingSent as u32 {
4794                         self.channel_state = ChannelState::ShutdownComplete as u32;
4795                 } else {
4796                         self.channel_state |= ChannelState::LocalShutdownSent as u32;
4797                 }
4798                 self.update_time_counter += 1;
4799
4800                 let monitor_update = if update_shutdown_script {
4801                         self.latest_monitor_update_id += 1;
4802                         Some(ChannelMonitorUpdate {
4803                                 update_id: self.latest_monitor_update_id,
4804                                 updates: vec![ChannelMonitorUpdateStep::ShutdownScript {
4805                                         scriptpubkey: self.get_closing_scriptpubkey(),
4806                                 }],
4807                         })
4808                 } else { None };
4809                 let shutdown = msgs::Shutdown {
4810                         channel_id: self.channel_id,
4811                         scriptpubkey: self.get_closing_scriptpubkey(),
4812                 };
4813
4814                 // Go ahead and drop holding cell updates as we'd rather fail payments than wait to send
4815                 // our shutdown until we've committed all of the pending changes.
4816                 self.holding_cell_update_fee = None;
4817                 let mut dropped_outbound_htlcs = Vec::with_capacity(self.holding_cell_htlc_updates.len());
4818                 self.holding_cell_htlc_updates.retain(|htlc_update| {
4819                         match htlc_update {
4820                                 &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, ref source, .. } => {
4821                                         dropped_outbound_htlcs.push((source.clone(), payment_hash.clone()));
4822                                         false
4823                                 },
4824                                 _ => true
4825                         }
4826                 });
4827
4828                 Ok((shutdown, monitor_update, dropped_outbound_htlcs))
4829         }
4830
4831         /// Gets the latest commitment transaction and any dependent transactions for relay (forcing
4832         /// shutdown of this channel - no more calls into this Channel may be made afterwards except
4833         /// those explicitly stated to be allowed after shutdown completes, eg some simple getters).
4834         /// Also returns the list of payment_hashes for channels which we can safely fail backwards
4835         /// immediately (others we will have to allow to time out).
4836         pub fn force_shutdown(&mut self, should_broadcast: bool) -> (Option<(OutPoint, ChannelMonitorUpdate)>, Vec<(HTLCSource, PaymentHash)>) {
4837                 // Note that we MUST only generate a monitor update that indicates force-closure - we're
4838                 // called during initialization prior to the chain_monitor in the encompassing ChannelManager
4839                 // being fully configured in some cases. Thus, its likely any monitor events we generate will
4840                 // be delayed in being processed! See the docs for `ChannelManagerReadArgs` for more.
4841                 assert!(self.channel_state != ChannelState::ShutdownComplete as u32);
4842
4843                 // We go ahead and "free" any holding cell HTLCs or HTLCs we haven't yet committed to and
4844                 // return them to fail the payment.
4845                 let mut dropped_outbound_htlcs = Vec::with_capacity(self.holding_cell_htlc_updates.len());
4846                 for htlc_update in self.holding_cell_htlc_updates.drain(..) {
4847                         match htlc_update {
4848                                 HTLCUpdateAwaitingACK::AddHTLC { source, payment_hash, .. } => {
4849                                         dropped_outbound_htlcs.push((source, payment_hash));
4850                                 },
4851                                 _ => {}
4852                         }
4853                 }
4854                 let monitor_update = if let Some(funding_txo) = self.get_funding_txo() {
4855                         // If we haven't yet exchanged funding signatures (ie channel_state < FundingSent),
4856                         // returning a channel monitor update here would imply a channel monitor update before
4857                         // we even registered the channel monitor to begin with, which is invalid.
4858                         // Thus, if we aren't actually at a point where we could conceivably broadcast the
4859                         // funding transaction, don't return a funding txo (which prevents providing the
4860                         // monitor update to the user, even if we return one).
4861                         // See test_duplicate_chan_id and test_pre_lockin_no_chan_closed_update for more.
4862                         if self.channel_state & (ChannelState::FundingSent as u32 | ChannelState::ChannelFunded as u32 | ChannelState::ShutdownComplete as u32) != 0 {
4863                                 self.latest_monitor_update_id += 1;
4864                                 Some((funding_txo, ChannelMonitorUpdate {
4865                                         update_id: self.latest_monitor_update_id,
4866                                         updates: vec![ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast }],
4867                                 }))
4868                         } else { None }
4869                 } else { None };
4870
4871                 self.channel_state = ChannelState::ShutdownComplete as u32;
4872                 self.update_time_counter += 1;
4873                 (monitor_update, dropped_outbound_htlcs)
4874         }
4875 }
4876
4877 const SERIALIZATION_VERSION: u8 = 2;
4878 const MIN_SERIALIZATION_VERSION: u8 = 1;
4879
4880 impl_writeable_tlv_based_enum!(InboundHTLCRemovalReason,;
4881         (0, FailRelay),
4882         (1, FailMalformed),
4883         (2, Fulfill),
4884 );
4885
4886 impl Writeable for ChannelUpdateStatus {
4887         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
4888                 // We only care about writing out the current state as it was announced, ie only either
4889                 // Enabled or Disabled. In the case of DisabledStaged, we most recently announced the
4890                 // channel as enabled, so we write 0. For EnabledStaged, we similarly write a 1.
4891                 match self {
4892                         ChannelUpdateStatus::Enabled => 0u8.write(writer)?,
4893                         ChannelUpdateStatus::DisabledStaged => 0u8.write(writer)?,
4894                         ChannelUpdateStatus::EnabledStaged => 1u8.write(writer)?,
4895                         ChannelUpdateStatus::Disabled => 1u8.write(writer)?,
4896                 }
4897                 Ok(())
4898         }
4899 }
4900
4901 impl Readable for ChannelUpdateStatus {
4902         fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
4903                 Ok(match <u8 as Readable>::read(reader)? {
4904                         0 => ChannelUpdateStatus::Enabled,
4905                         1 => ChannelUpdateStatus::Disabled,
4906                         _ => return Err(DecodeError::InvalidValue),
4907                 })
4908         }
4909 }
4910
4911 impl<Signer: Sign> Writeable for Channel<Signer> {
4912         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
4913                 // Note that we write out as if remove_uncommitted_htlcs_and_mark_paused had just been
4914                 // called.
4915
4916                 write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
4917
4918                 self.user_id.write(writer)?;
4919
4920                 // Write out the old serialization for the config object. This is read by version-1
4921                 // deserializers, but we will read the version in the TLV at the end instead.
4922                 self.config.forwarding_fee_proportional_millionths.write(writer)?;
4923                 self.config.cltv_expiry_delta.write(writer)?;
4924                 self.config.announced_channel.write(writer)?;
4925                 self.config.commit_upfront_shutdown_pubkey.write(writer)?;
4926
4927                 self.channel_id.write(writer)?;
4928                 (self.channel_state | ChannelState::PeerDisconnected as u32).write(writer)?;
4929                 self.channel_value_satoshis.write(writer)?;
4930
4931                 self.latest_monitor_update_id.write(writer)?;
4932
4933                 let mut key_data = VecWriter(Vec::new());
4934                 self.holder_signer.write(&mut key_data)?;
4935                 assert!(key_data.0.len() < core::usize::MAX);
4936                 assert!(key_data.0.len() < core::u32::MAX as usize);
4937                 (key_data.0.len() as u32).write(writer)?;
4938                 writer.write_all(&key_data.0[..])?;
4939
4940                 // Write out the old serialization for shutdown_pubkey for backwards compatibility, if
4941                 // deserialized from that format.
4942                 match self.shutdown_scriptpubkey.as_ref().and_then(|script| script.as_legacy_pubkey()) {
4943                         Some(shutdown_pubkey) => shutdown_pubkey.write(writer)?,
4944                         None => [0u8; PUBLIC_KEY_SIZE].write(writer)?,
4945                 }
4946                 self.destination_script.write(writer)?;
4947
4948                 self.cur_holder_commitment_transaction_number.write(writer)?;
4949                 self.cur_counterparty_commitment_transaction_number.write(writer)?;
4950                 self.value_to_self_msat.write(writer)?;
4951
4952                 let mut dropped_inbound_htlcs = 0;
4953                 for htlc in self.pending_inbound_htlcs.iter() {
4954                         if let InboundHTLCState::RemoteAnnounced(_) = htlc.state {
4955                                 dropped_inbound_htlcs += 1;
4956                         }
4957                 }
4958                 (self.pending_inbound_htlcs.len() as u64 - dropped_inbound_htlcs).write(writer)?;
4959                 for htlc in self.pending_inbound_htlcs.iter() {
4960                         if let &InboundHTLCState::RemoteAnnounced(_) = &htlc.state {
4961                                 continue; // Drop
4962                         }
4963                         htlc.htlc_id.write(writer)?;
4964                         htlc.amount_msat.write(writer)?;
4965                         htlc.cltv_expiry.write(writer)?;
4966                         htlc.payment_hash.write(writer)?;
4967                         match &htlc.state {
4968                                 &InboundHTLCState::RemoteAnnounced(_) => unreachable!(),
4969                                 &InboundHTLCState::AwaitingRemoteRevokeToAnnounce(ref htlc_state) => {
4970                                         1u8.write(writer)?;
4971                                         htlc_state.write(writer)?;
4972                                 },
4973                                 &InboundHTLCState::AwaitingAnnouncedRemoteRevoke(ref htlc_state) => {
4974                                         2u8.write(writer)?;
4975                                         htlc_state.write(writer)?;
4976                                 },
4977                                 &InboundHTLCState::Committed => {
4978                                         3u8.write(writer)?;
4979                                 },
4980                                 &InboundHTLCState::LocalRemoved(ref removal_reason) => {
4981                                         4u8.write(writer)?;
4982                                         removal_reason.write(writer)?;
4983                                 },
4984                         }
4985                 }
4986
4987                 (self.pending_outbound_htlcs.len() as u64).write(writer)?;
4988                 for htlc in self.pending_outbound_htlcs.iter() {
4989                         htlc.htlc_id.write(writer)?;
4990                         htlc.amount_msat.write(writer)?;
4991                         htlc.cltv_expiry.write(writer)?;
4992                         htlc.payment_hash.write(writer)?;
4993                         htlc.source.write(writer)?;
4994                         match &htlc.state {
4995                                 &OutboundHTLCState::LocalAnnounced(ref onion_packet) => {
4996                                         0u8.write(writer)?;
4997                                         onion_packet.write(writer)?;
4998                                 },
4999                                 &OutboundHTLCState::Committed => {
5000                                         1u8.write(writer)?;
5001                                 },
5002                                 &OutboundHTLCState::RemoteRemoved(_) => {
5003                                         // Treat this as a Committed because we haven't received the CS - they'll
5004                                         // resend the claim/fail on reconnect as we all (hopefully) the missing CS.
5005                                         1u8.write(writer)?;
5006                                 },
5007                                 &OutboundHTLCState::AwaitingRemoteRevokeToRemove(ref fail_reason) => {
5008                                         3u8.write(writer)?;
5009                                         fail_reason.write(writer)?;
5010                                 },
5011                                 &OutboundHTLCState::AwaitingRemovedRemoteRevoke(ref fail_reason) => {
5012                                         4u8.write(writer)?;
5013                                         fail_reason.write(writer)?;
5014                                 },
5015                         }
5016                 }
5017
5018                 (self.holding_cell_htlc_updates.len() as u64).write(writer)?;
5019                 for update in self.holding_cell_htlc_updates.iter() {
5020                         match update {
5021                                 &HTLCUpdateAwaitingACK::AddHTLC { ref amount_msat, ref cltv_expiry, ref payment_hash, ref source, ref onion_routing_packet } => {
5022                                         0u8.write(writer)?;
5023                                         amount_msat.write(writer)?;
5024                                         cltv_expiry.write(writer)?;
5025                                         payment_hash.write(writer)?;
5026                                         source.write(writer)?;
5027                                         onion_routing_packet.write(writer)?;
5028                                 },
5029                                 &HTLCUpdateAwaitingACK::ClaimHTLC { ref payment_preimage, ref htlc_id } => {
5030                                         1u8.write(writer)?;
5031                                         payment_preimage.write(writer)?;
5032                                         htlc_id.write(writer)?;
5033                                 },
5034                                 &HTLCUpdateAwaitingACK::FailHTLC { ref htlc_id, ref err_packet } => {
5035                                         2u8.write(writer)?;
5036                                         htlc_id.write(writer)?;
5037                                         err_packet.write(writer)?;
5038                                 }
5039                         }
5040                 }
5041
5042                 match self.resend_order {
5043                         RAACommitmentOrder::CommitmentFirst => 0u8.write(writer)?,
5044                         RAACommitmentOrder::RevokeAndACKFirst => 1u8.write(writer)?,
5045                 }
5046
5047                 self.monitor_pending_funding_locked.write(writer)?;
5048                 self.monitor_pending_revoke_and_ack.write(writer)?;
5049                 self.monitor_pending_commitment_signed.write(writer)?;
5050
5051                 (self.monitor_pending_forwards.len() as u64).write(writer)?;
5052                 for &(ref pending_forward, ref htlc_id) in self.monitor_pending_forwards.iter() {
5053                         pending_forward.write(writer)?;
5054                         htlc_id.write(writer)?;
5055                 }
5056
5057                 (self.monitor_pending_failures.len() as u64).write(writer)?;
5058                 for &(ref htlc_source, ref payment_hash, ref fail_reason) in self.monitor_pending_failures.iter() {
5059                         htlc_source.write(writer)?;
5060                         payment_hash.write(writer)?;
5061                         fail_reason.write(writer)?;
5062                 }
5063
5064                 if self.is_outbound() {
5065                         self.pending_update_fee.map(|(a, _)| a).write(writer)?;
5066                 } else if let Some((feerate, FeeUpdateState::AwaitingRemoteRevokeToAnnounce)) = self.pending_update_fee {
5067                         // As for inbound HTLCs, if the update was only announced and never committed, drop it.
5068                         Some(feerate).write(writer)?;
5069                 } else {
5070                         None::<u32>.write(writer)?;
5071                 }
5072                 self.holding_cell_update_fee.write(writer)?;
5073
5074                 self.next_holder_htlc_id.write(writer)?;
5075                 (self.next_counterparty_htlc_id - dropped_inbound_htlcs).write(writer)?;
5076                 self.update_time_counter.write(writer)?;
5077                 self.feerate_per_kw.write(writer)?;
5078
5079                 // Versions prior to 0.0.100 expected to read the fields of `last_sent_closing_fee` here,
5080                 // however we are supposed to restart shutdown fee negotiation on reconnect (and wipe
5081                 // `last_send_closing_fee` in `remove_uncommitted_htlcs_and_mark_paused`) so we should never
5082                 // consider the stale state on reload.
5083                 0u8.write(writer)?;
5084
5085                 self.funding_tx_confirmed_in.write(writer)?;
5086                 self.funding_tx_confirmation_height.write(writer)?;
5087                 self.short_channel_id.write(writer)?;
5088
5089                 self.counterparty_dust_limit_satoshis.write(writer)?;
5090                 self.holder_dust_limit_satoshis.write(writer)?;
5091                 self.counterparty_max_htlc_value_in_flight_msat.write(writer)?;
5092
5093                 // Note that this field is ignored by 0.0.99+ as the TLV Optional variant is used instead.
5094                 self.counterparty_selected_channel_reserve_satoshis.unwrap_or(0).write(writer)?;
5095
5096                 self.counterparty_htlc_minimum_msat.write(writer)?;
5097                 self.holder_htlc_minimum_msat.write(writer)?;
5098                 self.counterparty_max_accepted_htlcs.write(writer)?;
5099
5100                 // Note that this field is ignored by 0.0.99+ as the TLV Optional variant is used instead.
5101                 self.minimum_depth.unwrap_or(0).write(writer)?;
5102
5103                 match &self.counterparty_forwarding_info {
5104                         Some(info) => {
5105                                 1u8.write(writer)?;
5106                                 info.fee_base_msat.write(writer)?;
5107                                 info.fee_proportional_millionths.write(writer)?;
5108                                 info.cltv_expiry_delta.write(writer)?;
5109                         },
5110                         None => 0u8.write(writer)?
5111                 }
5112
5113                 self.channel_transaction_parameters.write(writer)?;
5114                 self.funding_transaction.write(writer)?;
5115
5116                 self.counterparty_cur_commitment_point.write(writer)?;
5117                 self.counterparty_prev_commitment_point.write(writer)?;
5118                 self.counterparty_node_id.write(writer)?;
5119
5120                 self.counterparty_shutdown_scriptpubkey.write(writer)?;
5121
5122                 self.commitment_secrets.write(writer)?;
5123
5124                 self.channel_update_status.write(writer)?;
5125
5126                 #[cfg(any(test, feature = "fuzztarget"))]
5127                 (self.historical_inbound_htlc_fulfills.len() as u64).write(writer)?;
5128                 #[cfg(any(test, feature = "fuzztarget"))]
5129                 for htlc in self.historical_inbound_htlc_fulfills.iter() {
5130                         htlc.write(writer)?;
5131                 }
5132
5133                 write_tlv_fields!(writer, {
5134                         (0, self.announcement_sigs, option),
5135                         // minimum_depth and counterparty_selected_channel_reserve_satoshis used to have a
5136                         // default value instead of being Option<>al. Thus, to maintain compatibility we write
5137                         // them twice, once with their original default values above, and once as an option
5138                         // here. On the read side, old versions will simply ignore the odd-type entries here,
5139                         // and new versions map the default values to None and allow the TLV entries here to
5140                         // override that.
5141                         (1, self.minimum_depth, option),
5142                         (3, self.counterparty_selected_channel_reserve_satoshis, option),
5143                         (5, self.config, required),
5144                         (7, self.shutdown_scriptpubkey, option),
5145                         (9, self.target_closing_feerate_sats_per_kw, option),
5146                 });
5147
5148                 Ok(())
5149         }
5150 }
5151
5152 const MAX_ALLOC_SIZE: usize = 64*1024;
5153 impl<'a, Signer: Sign, K: Deref> ReadableArgs<&'a K> for Channel<Signer>
5154                 where K::Target: KeysInterface<Signer = Signer> {
5155         fn read<R : io::Read>(reader: &mut R, keys_source: &'a K) -> Result<Self, DecodeError> {
5156                 let ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
5157
5158                 let user_id = Readable::read(reader)?;
5159
5160                 let mut config = Some(ChannelConfig::default());
5161                 if ver == 1 {
5162                         // Read the old serialization of the ChannelConfig from version 0.0.98.
5163                         config.as_mut().unwrap().forwarding_fee_proportional_millionths = Readable::read(reader)?;
5164                         config.as_mut().unwrap().cltv_expiry_delta = Readable::read(reader)?;
5165                         config.as_mut().unwrap().announced_channel = Readable::read(reader)?;
5166                         config.as_mut().unwrap().commit_upfront_shutdown_pubkey = Readable::read(reader)?;
5167                 } else {
5168                         // Read the 8 bytes of backwards-compatibility ChannelConfig data.
5169                         let mut _val: u64 = Readable::read(reader)?;
5170                 }
5171
5172                 let channel_id = Readable::read(reader)?;
5173                 let channel_state = Readable::read(reader)?;
5174                 let channel_value_satoshis = Readable::read(reader)?;
5175
5176                 let latest_monitor_update_id = Readable::read(reader)?;
5177
5178                 let keys_len: u32 = Readable::read(reader)?;
5179                 let mut keys_data = Vec::with_capacity(cmp::min(keys_len as usize, MAX_ALLOC_SIZE));
5180                 while keys_data.len() != keys_len as usize {
5181                         // Read 1KB at a time to avoid accidentally allocating 4GB on corrupted channel keys
5182                         let mut data = [0; 1024];
5183                         let read_slice = &mut data[0..cmp::min(1024, keys_len as usize - keys_data.len())];
5184                         reader.read_exact(read_slice)?;
5185                         keys_data.extend_from_slice(read_slice);
5186                 }
5187                 let holder_signer = keys_source.read_chan_signer(&keys_data)?;
5188
5189                 // Read the old serialization for shutdown_pubkey, preferring the TLV field later if set.
5190                 let mut shutdown_scriptpubkey = match <PublicKey as Readable>::read(reader) {
5191                         Ok(pubkey) => Some(ShutdownScript::new_p2wpkh_from_pubkey(pubkey)),
5192                         Err(_) => None,
5193                 };
5194                 let destination_script = Readable::read(reader)?;
5195
5196                 let cur_holder_commitment_transaction_number = Readable::read(reader)?;
5197                 let cur_counterparty_commitment_transaction_number = Readable::read(reader)?;
5198                 let value_to_self_msat = Readable::read(reader)?;
5199
5200                 let pending_inbound_htlc_count: u64 = Readable::read(reader)?;
5201                 let mut pending_inbound_htlcs = Vec::with_capacity(cmp::min(pending_inbound_htlc_count as usize, OUR_MAX_HTLCS as usize));
5202                 for _ in 0..pending_inbound_htlc_count {
5203                         pending_inbound_htlcs.push(InboundHTLCOutput {
5204                                 htlc_id: Readable::read(reader)?,
5205                                 amount_msat: Readable::read(reader)?,
5206                                 cltv_expiry: Readable::read(reader)?,
5207                                 payment_hash: Readable::read(reader)?,
5208                                 state: match <u8 as Readable>::read(reader)? {
5209                                         1 => InboundHTLCState::AwaitingRemoteRevokeToAnnounce(Readable::read(reader)?),
5210                                         2 => InboundHTLCState::AwaitingAnnouncedRemoteRevoke(Readable::read(reader)?),
5211                                         3 => InboundHTLCState::Committed,
5212                                         4 => InboundHTLCState::LocalRemoved(Readable::read(reader)?),
5213                                         _ => return Err(DecodeError::InvalidValue),
5214                                 },
5215                         });
5216                 }
5217
5218                 let pending_outbound_htlc_count: u64 = Readable::read(reader)?;
5219                 let mut pending_outbound_htlcs = Vec::with_capacity(cmp::min(pending_outbound_htlc_count as usize, OUR_MAX_HTLCS as usize));
5220                 for _ in 0..pending_outbound_htlc_count {
5221                         pending_outbound_htlcs.push(OutboundHTLCOutput {
5222                                 htlc_id: Readable::read(reader)?,
5223                                 amount_msat: Readable::read(reader)?,
5224                                 cltv_expiry: Readable::read(reader)?,
5225                                 payment_hash: Readable::read(reader)?,
5226                                 source: Readable::read(reader)?,
5227                                 state: match <u8 as Readable>::read(reader)? {
5228                                         0 => OutboundHTLCState::LocalAnnounced(Box::new(Readable::read(reader)?)),
5229                                         1 => OutboundHTLCState::Committed,
5230                                         2 => OutboundHTLCState::RemoteRemoved(Readable::read(reader)?),
5231                                         3 => OutboundHTLCState::AwaitingRemoteRevokeToRemove(Readable::read(reader)?),
5232                                         4 => OutboundHTLCState::AwaitingRemovedRemoteRevoke(Readable::read(reader)?),
5233                                         _ => return Err(DecodeError::InvalidValue),
5234                                 },
5235                         });
5236                 }
5237
5238                 let holding_cell_htlc_update_count: u64 = Readable::read(reader)?;
5239                 let mut holding_cell_htlc_updates = Vec::with_capacity(cmp::min(holding_cell_htlc_update_count as usize, OUR_MAX_HTLCS as usize*2));
5240                 for _ in 0..holding_cell_htlc_update_count {
5241                         holding_cell_htlc_updates.push(match <u8 as Readable>::read(reader)? {
5242                                 0 => HTLCUpdateAwaitingACK::AddHTLC {
5243                                         amount_msat: Readable::read(reader)?,
5244                                         cltv_expiry: Readable::read(reader)?,
5245                                         payment_hash: Readable::read(reader)?,
5246                                         source: Readable::read(reader)?,
5247                                         onion_routing_packet: Readable::read(reader)?,
5248                                 },
5249                                 1 => HTLCUpdateAwaitingACK::ClaimHTLC {
5250                                         payment_preimage: Readable::read(reader)?,
5251                                         htlc_id: Readable::read(reader)?,
5252                                 },
5253                                 2 => HTLCUpdateAwaitingACK::FailHTLC {
5254                                         htlc_id: Readable::read(reader)?,
5255                                         err_packet: Readable::read(reader)?,
5256                                 },
5257                                 _ => return Err(DecodeError::InvalidValue),
5258                         });
5259                 }
5260
5261                 let resend_order = match <u8 as Readable>::read(reader)? {
5262                         0 => RAACommitmentOrder::CommitmentFirst,
5263                         1 => RAACommitmentOrder::RevokeAndACKFirst,
5264                         _ => return Err(DecodeError::InvalidValue),
5265                 };
5266
5267                 let monitor_pending_funding_locked = Readable::read(reader)?;
5268                 let monitor_pending_revoke_and_ack = Readable::read(reader)?;
5269                 let monitor_pending_commitment_signed = Readable::read(reader)?;
5270
5271                 let monitor_pending_forwards_count: u64 = Readable::read(reader)?;
5272                 let mut monitor_pending_forwards = Vec::with_capacity(cmp::min(monitor_pending_forwards_count as usize, OUR_MAX_HTLCS as usize));
5273                 for _ in 0..monitor_pending_forwards_count {
5274                         monitor_pending_forwards.push((Readable::read(reader)?, Readable::read(reader)?));
5275                 }
5276
5277                 let monitor_pending_failures_count: u64 = Readable::read(reader)?;
5278                 let mut monitor_pending_failures = Vec::with_capacity(cmp::min(monitor_pending_failures_count as usize, OUR_MAX_HTLCS as usize));
5279                 for _ in 0..monitor_pending_failures_count {
5280                         monitor_pending_failures.push((Readable::read(reader)?, Readable::read(reader)?, Readable::read(reader)?));
5281                 }
5282
5283                 let pending_update_fee_value: Option<u32> = Readable::read(reader)?;
5284
5285                 let holding_cell_update_fee = Readable::read(reader)?;
5286
5287                 let next_holder_htlc_id = Readable::read(reader)?;
5288                 let next_counterparty_htlc_id = Readable::read(reader)?;
5289                 let update_time_counter = Readable::read(reader)?;
5290                 let feerate_per_kw = Readable::read(reader)?;
5291
5292                 // Versions prior to 0.0.100 expected to read the fields of `last_sent_closing_fee` here,
5293                 // however we are supposed to restart shutdown fee negotiation on reconnect (and wipe
5294                 // `last_send_closing_fee` in `remove_uncommitted_htlcs_and_mark_paused`) so we should never
5295                 // consider the stale state on reload.
5296                 match <u8 as Readable>::read(reader)? {
5297                         0 => {},
5298                         1 => {
5299                                 let _: u32 = Readable::read(reader)?;
5300                                 let _: u64 = Readable::read(reader)?;
5301                                 let _: Signature = Readable::read(reader)?;
5302                         },
5303                         _ => return Err(DecodeError::InvalidValue),
5304                 }
5305
5306                 let funding_tx_confirmed_in = Readable::read(reader)?;
5307                 let funding_tx_confirmation_height = Readable::read(reader)?;
5308                 let short_channel_id = Readable::read(reader)?;
5309
5310                 let counterparty_dust_limit_satoshis = Readable::read(reader)?;
5311                 let holder_dust_limit_satoshis = Readable::read(reader)?;
5312                 let counterparty_max_htlc_value_in_flight_msat = Readable::read(reader)?;
5313                 let mut counterparty_selected_channel_reserve_satoshis = None;
5314                 if ver == 1 {
5315                         // Read the old serialization from version 0.0.98.
5316                         counterparty_selected_channel_reserve_satoshis = Some(Readable::read(reader)?);
5317                 } else {
5318                         // Read the 8 bytes of backwards-compatibility data.
5319                         let _dummy: u64 = Readable::read(reader)?;
5320                 }
5321                 let counterparty_htlc_minimum_msat = Readable::read(reader)?;
5322                 let holder_htlc_minimum_msat = Readable::read(reader)?;
5323                 let counterparty_max_accepted_htlcs = Readable::read(reader)?;
5324
5325                 let mut minimum_depth = None;
5326                 if ver == 1 {
5327                         // Read the old serialization from version 0.0.98.
5328                         minimum_depth = Some(Readable::read(reader)?);
5329                 } else {
5330                         // Read the 4 bytes of backwards-compatibility data.
5331                         let _dummy: u32 = Readable::read(reader)?;
5332                 }
5333
5334                 let counterparty_forwarding_info = match <u8 as Readable>::read(reader)? {
5335                         0 => None,
5336                         1 => Some(CounterpartyForwardingInfo {
5337                                 fee_base_msat: Readable::read(reader)?,
5338                                 fee_proportional_millionths: Readable::read(reader)?,
5339                                 cltv_expiry_delta: Readable::read(reader)?,
5340                         }),
5341                         _ => return Err(DecodeError::InvalidValue),
5342                 };
5343
5344                 let channel_parameters: ChannelTransactionParameters = Readable::read(reader)?;
5345                 let funding_transaction = Readable::read(reader)?;
5346
5347                 let counterparty_cur_commitment_point = Readable::read(reader)?;
5348
5349                 let counterparty_prev_commitment_point = Readable::read(reader)?;
5350                 let counterparty_node_id = Readable::read(reader)?;
5351
5352                 let counterparty_shutdown_scriptpubkey = Readable::read(reader)?;
5353                 let commitment_secrets = Readable::read(reader)?;
5354
5355                 let channel_update_status = Readable::read(reader)?;
5356
5357                 #[cfg(any(test, feature = "fuzztarget"))]
5358                 let mut historical_inbound_htlc_fulfills = HashSet::new();
5359                 #[cfg(any(test, feature = "fuzztarget"))]
5360                 {
5361                         let htlc_fulfills_len: u64 = Readable::read(reader)?;
5362                         for _ in 0..htlc_fulfills_len {
5363                                 assert!(historical_inbound_htlc_fulfills.insert(Readable::read(reader)?));
5364                         }
5365                 }
5366
5367                 let pending_update_fee = if let Some(feerate) = pending_update_fee_value {
5368                         Some((feerate, if channel_parameters.is_outbound_from_holder {
5369                                 FeeUpdateState::Outbound
5370                         } else {
5371                                 FeeUpdateState::AwaitingRemoteRevokeToAnnounce
5372                         }))
5373                 } else {
5374                         None
5375                 };
5376
5377                 let mut announcement_sigs = None;
5378                 let mut target_closing_feerate_sats_per_kw = None;
5379                 read_tlv_fields!(reader, {
5380                         (0, announcement_sigs, option),
5381                         (1, minimum_depth, option),
5382                         (3, counterparty_selected_channel_reserve_satoshis, option),
5383                         (5, config, option), // Note that if none is provided we will *not* overwrite the existing one.
5384                         (7, shutdown_scriptpubkey, option),
5385                         (9, target_closing_feerate_sats_per_kw, option),
5386                 });
5387
5388                 let mut secp_ctx = Secp256k1::new();
5389                 secp_ctx.seeded_randomize(&keys_source.get_secure_random_bytes());
5390
5391                 Ok(Channel {
5392                         user_id,
5393
5394                         config: config.unwrap(),
5395                         channel_id,
5396                         channel_state,
5397                         secp_ctx,
5398                         channel_value_satoshis,
5399
5400                         latest_monitor_update_id,
5401
5402                         holder_signer,
5403                         shutdown_scriptpubkey,
5404                         destination_script,
5405
5406                         cur_holder_commitment_transaction_number,
5407                         cur_counterparty_commitment_transaction_number,
5408                         value_to_self_msat,
5409
5410                         pending_inbound_htlcs,
5411                         pending_outbound_htlcs,
5412                         holding_cell_htlc_updates,
5413
5414                         resend_order,
5415
5416                         monitor_pending_funding_locked,
5417                         monitor_pending_revoke_and_ack,
5418                         monitor_pending_commitment_signed,
5419                         monitor_pending_forwards,
5420                         monitor_pending_failures,
5421
5422                         pending_update_fee,
5423                         holding_cell_update_fee,
5424                         next_holder_htlc_id,
5425                         next_counterparty_htlc_id,
5426                         update_time_counter,
5427                         feerate_per_kw,
5428
5429                         #[cfg(debug_assertions)]
5430                         holder_max_commitment_tx_output: Mutex::new((0, 0)),
5431                         #[cfg(debug_assertions)]
5432                         counterparty_max_commitment_tx_output: Mutex::new((0, 0)),
5433
5434                         last_sent_closing_fee: None,
5435                         pending_counterparty_closing_signed: None,
5436                         closing_fee_limits: None,
5437                         target_closing_feerate_sats_per_kw,
5438
5439                         funding_tx_confirmed_in,
5440                         funding_tx_confirmation_height,
5441                         short_channel_id,
5442
5443                         counterparty_dust_limit_satoshis,
5444                         holder_dust_limit_satoshis,
5445                         counterparty_max_htlc_value_in_flight_msat,
5446                         counterparty_selected_channel_reserve_satoshis,
5447                         counterparty_htlc_minimum_msat,
5448                         holder_htlc_minimum_msat,
5449                         counterparty_max_accepted_htlcs,
5450                         minimum_depth,
5451
5452                         counterparty_forwarding_info,
5453
5454                         channel_transaction_parameters: channel_parameters,
5455                         funding_transaction,
5456
5457                         counterparty_cur_commitment_point,
5458                         counterparty_prev_commitment_point,
5459                         counterparty_node_id,
5460
5461                         counterparty_shutdown_scriptpubkey,
5462
5463                         commitment_secrets,
5464
5465                         channel_update_status,
5466
5467                         announcement_sigs,
5468
5469                         #[cfg(any(test, feature = "fuzztarget"))]
5470                         next_local_commitment_tx_fee_info_cached: Mutex::new(None),
5471                         #[cfg(any(test, feature = "fuzztarget"))]
5472                         next_remote_commitment_tx_fee_info_cached: Mutex::new(None),
5473
5474                         workaround_lnd_bug_4006: None,
5475
5476                         #[cfg(any(test, feature = "fuzztarget"))]
5477                         historical_inbound_htlc_fulfills,
5478                 })
5479         }
5480 }
5481
5482 #[cfg(test)]
5483 mod tests {
5484         use bitcoin::util::bip143;
5485         use bitcoin::consensus::encode::serialize;
5486         use bitcoin::blockdata::script::{Script, Builder};
5487         use bitcoin::blockdata::transaction::{Transaction, TxOut, SigHashType};
5488         use bitcoin::blockdata::constants::genesis_block;
5489         use bitcoin::blockdata::opcodes;
5490         use bitcoin::network::constants::Network;
5491         use bitcoin::hashes::hex::FromHex;
5492         use hex;
5493         use ln::{PaymentPreimage, PaymentHash};
5494         use ln::channelmanager::HTLCSource;
5495         use ln::channel::{Channel,InboundHTLCOutput,OutboundHTLCOutput,InboundHTLCState,OutboundHTLCState,HTLCOutputInCommitment,HTLCCandidate,HTLCInitiator,TxCreationKeys};
5496         use ln::channel::MAX_FUNDING_SATOSHIS;
5497         use ln::features::InitFeatures;
5498         use ln::msgs::{ChannelUpdate, DataLossProtect, DecodeError, OptionalField, UnsignedChannelUpdate};
5499         use ln::script::ShutdownScript;
5500         use ln::chan_utils;
5501         use ln::chan_utils::{ChannelPublicKeys, HolderCommitmentTransaction, CounterpartyChannelTransactionParameters, HTLC_SUCCESS_TX_WEIGHT, HTLC_TIMEOUT_TX_WEIGHT};
5502         use chain::BestBlock;
5503         use chain::chaininterface::{FeeEstimator,ConfirmationTarget};
5504         use chain::keysinterface::{InMemorySigner, KeysInterface, BaseSign};
5505         use chain::transaction::OutPoint;
5506         use util::config::UserConfig;
5507         use util::enforcing_trait_impls::EnforcingSigner;
5508         use util::errors::APIError;
5509         use util::test_utils;
5510         use util::test_utils::OnGetShutdownScriptpubkey;
5511         use util::logger::Logger;
5512         use bitcoin::secp256k1::{Secp256k1, Message, Signature, All};
5513         use bitcoin::secp256k1::ffi::Signature as FFISignature;
5514         use bitcoin::secp256k1::key::{SecretKey,PublicKey};
5515         use bitcoin::secp256k1::recovery::RecoverableSignature;
5516         use bitcoin::hashes::sha256::Hash as Sha256;
5517         use bitcoin::hashes::Hash;
5518         use bitcoin::hash_types::{Txid, WPubkeyHash};
5519         use core::num::NonZeroU8;
5520         use sync::Arc;
5521         use prelude::*;
5522
5523         struct TestFeeEstimator {
5524                 fee_est: u32
5525         }
5526         impl FeeEstimator for TestFeeEstimator {
5527                 fn get_est_sat_per_1000_weight(&self, _: ConfirmationTarget) -> u32 {
5528                         self.fee_est
5529                 }
5530         }
5531
5532         #[test]
5533         fn test_max_funding_satoshis() {
5534                 assert!(MAX_FUNDING_SATOSHIS <= 21_000_000 * 100_000_000,
5535                         "MAX_FUNDING_SATOSHIS is greater than all satoshis in existence");
5536         }
5537
5538         struct Keys {
5539                 signer: InMemorySigner,
5540         }
5541         impl KeysInterface for Keys {
5542                 type Signer = InMemorySigner;
5543
5544                 fn get_node_secret(&self) -> SecretKey { panic!(); }
5545                 fn get_destination_script(&self) -> Script {
5546                         let secp_ctx = Secp256k1::signing_only();
5547                         let channel_monitor_claim_key = SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap();
5548                         let channel_monitor_claim_key_hash = WPubkeyHash::hash(&PublicKey::from_secret_key(&secp_ctx, &channel_monitor_claim_key).serialize());
5549                         Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&channel_monitor_claim_key_hash[..]).into_script()
5550                 }
5551
5552                 fn get_shutdown_scriptpubkey(&self) -> ShutdownScript {
5553                         let secp_ctx = Secp256k1::signing_only();
5554                         let channel_close_key = SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap();
5555                         ShutdownScript::new_p2wpkh_from_pubkey(PublicKey::from_secret_key(&secp_ctx, &channel_close_key))
5556                 }
5557
5558                 fn get_channel_signer(&self, _inbound: bool, _channel_value_satoshis: u64) -> InMemorySigner {
5559                         self.signer.clone()
5560                 }
5561                 fn get_secure_random_bytes(&self) -> [u8; 32] { [0; 32] }
5562                 fn read_chan_signer(&self, _data: &[u8]) -> Result<Self::Signer, DecodeError> { panic!(); }
5563                 fn sign_invoice(&self, _invoice_preimage: Vec<u8>) -> Result<RecoverableSignature, ()> { panic!(); }
5564         }
5565
5566         fn public_from_secret_hex(secp_ctx: &Secp256k1<All>, hex: &str) -> PublicKey {
5567                 PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode(hex).unwrap()[..]).unwrap())
5568         }
5569
5570         #[test]
5571         fn upfront_shutdown_script_incompatibility() {
5572                 let features = InitFeatures::known().clear_shutdown_anysegwit();
5573                 let non_v0_segwit_shutdown_script =
5574                         ShutdownScript::new_witness_program(NonZeroU8::new(16).unwrap(), &[0, 40]).unwrap();
5575
5576                 let seed = [42; 32];
5577                 let network = Network::Testnet;
5578                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
5579                 keys_provider.expect(OnGetShutdownScriptpubkey {
5580                         returns: non_v0_segwit_shutdown_script.clone(),
5581                 });
5582
5583                 let fee_estimator = TestFeeEstimator { fee_est: 253 };
5584                 let secp_ctx = Secp256k1::new();
5585                 let node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
5586                 let config = UserConfig::default();
5587                 match Channel::<EnforcingSigner>::new_outbound(&&fee_estimator, &&keys_provider, node_id, &features, 10000000, 100000, 42, &config) {
5588                         Err(APIError::IncompatibleShutdownScript { script }) => {
5589                                 assert_eq!(script.into_inner(), non_v0_segwit_shutdown_script.into_inner());
5590                         },
5591                         Err(e) => panic!("Unexpected error: {:?}", e),
5592                         Ok(_) => panic!("Expected error"),
5593                 }
5594         }
5595
5596         // Check that, during channel creation, we use the same feerate in the open channel message
5597         // as we do in the Channel object creation itself.
5598         #[test]
5599         fn test_open_channel_msg_fee() {
5600                 let original_fee = 253;
5601                 let mut fee_est = TestFeeEstimator{fee_est: original_fee };
5602                 let secp_ctx = Secp256k1::new();
5603                 let seed = [42; 32];
5604                 let network = Network::Testnet;
5605                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
5606
5607                 let node_a_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
5608                 let config = UserConfig::default();
5609                 let node_a_chan = Channel::<EnforcingSigner>::new_outbound(&&fee_est, &&keys_provider, node_a_node_id, &InitFeatures::known(), 10000000, 100000, 42, &config).unwrap();
5610
5611                 // Now change the fee so we can check that the fee in the open_channel message is the
5612                 // same as the old fee.
5613                 fee_est.fee_est = 500;
5614                 let open_channel_msg = node_a_chan.get_open_channel(genesis_block(network).header.block_hash());
5615                 assert_eq!(open_channel_msg.feerate_per_kw, original_fee);
5616         }
5617
5618         #[test]
5619         fn test_holder_vs_counterparty_dust_limit() {
5620                 // Test that when calculating the local and remote commitment transaction fees, the correct
5621                 // dust limits are used.
5622                 let feeest = TestFeeEstimator{fee_est: 15000};
5623                 let secp_ctx = Secp256k1::new();
5624                 let seed = [42; 32];
5625                 let network = Network::Testnet;
5626                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
5627
5628                 // Go through the flow of opening a channel between two nodes, making sure
5629                 // they have different dust limits.
5630
5631                 // Create Node A's channel pointing to Node B's pubkey
5632                 let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
5633                 let config = UserConfig::default();
5634                 let mut node_a_chan = Channel::<EnforcingSigner>::new_outbound(&&feeest, &&keys_provider, node_b_node_id, &InitFeatures::known(), 10000000, 100000, 42, &config).unwrap();
5635
5636                 // Create Node B's channel by receiving Node A's open_channel message
5637                 // Make sure A's dust limit is as we expect.
5638                 let open_channel_msg = node_a_chan.get_open_channel(genesis_block(network).header.block_hash());
5639                 let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[7; 32]).unwrap());
5640                 let node_b_chan = Channel::<EnforcingSigner>::new_from_req(&&feeest, &&keys_provider, node_b_node_id, &InitFeatures::known(), &open_channel_msg, 7, &config).unwrap();
5641
5642                 // Node B --> Node A: accept channel, explicitly setting B's dust limit.
5643                 let mut accept_channel_msg = node_b_chan.get_accept_channel();
5644                 accept_channel_msg.dust_limit_satoshis = 546;
5645                 node_a_chan.accept_channel(&accept_channel_msg, &config, &InitFeatures::known()).unwrap();
5646                 node_a_chan.holder_dust_limit_satoshis = 1560;
5647
5648                 // Put some inbound and outbound HTLCs in A's channel.
5649                 let htlc_amount_msat = 11_092_000; // put an amount below A's effective dust limit but above B's.
5650                 node_a_chan.pending_inbound_htlcs.push(InboundHTLCOutput {
5651                         htlc_id: 0,
5652                         amount_msat: htlc_amount_msat,
5653                         payment_hash: PaymentHash(Sha256::hash(&[42; 32]).into_inner()),
5654                         cltv_expiry: 300000000,
5655                         state: InboundHTLCState::Committed,
5656                 });
5657
5658                 node_a_chan.pending_outbound_htlcs.push(OutboundHTLCOutput {
5659                         htlc_id: 1,
5660                         amount_msat: htlc_amount_msat, // put an amount below A's dust amount but above B's.
5661                         payment_hash: PaymentHash(Sha256::hash(&[43; 32]).into_inner()),
5662                         cltv_expiry: 200000000,
5663                         state: OutboundHTLCState::Committed,
5664                         source: HTLCSource::OutboundRoute {
5665                                 path: Vec::new(),
5666                                 session_priv: SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap(),
5667                                 first_hop_htlc_msat: 548,
5668                         }
5669                 });
5670
5671                 // Make sure when Node A calculates their local commitment transaction, none of the HTLCs pass
5672                 // the dust limit check.
5673                 let htlc_candidate = HTLCCandidate::new(htlc_amount_msat, HTLCInitiator::LocalOffered);
5674                 let local_commit_tx_fee = node_a_chan.next_local_commit_tx_fee_msat(htlc_candidate, None);
5675                 let local_commit_fee_0_htlcs = node_a_chan.commit_tx_fee_msat(0);
5676                 assert_eq!(local_commit_tx_fee, local_commit_fee_0_htlcs);
5677
5678                 // Finally, make sure that when Node A calculates the remote's commitment transaction fees, all
5679                 // of the HTLCs are seen to be above the dust limit.
5680                 node_a_chan.channel_transaction_parameters.is_outbound_from_holder = false;
5681                 let remote_commit_fee_3_htlcs = node_a_chan.commit_tx_fee_msat(3);
5682                 let htlc_candidate = HTLCCandidate::new(htlc_amount_msat, HTLCInitiator::LocalOffered);
5683                 let remote_commit_tx_fee = node_a_chan.next_remote_commit_tx_fee_msat(htlc_candidate, None);
5684                 assert_eq!(remote_commit_tx_fee, remote_commit_fee_3_htlcs);
5685         }
5686
5687         #[test]
5688         fn test_timeout_vs_success_htlc_dust_limit() {
5689                 // Make sure that when `next_remote_commit_tx_fee_msat` and `next_local_commit_tx_fee_msat`
5690                 // calculate the real dust limits for HTLCs (i.e. the dust limit given by the counterparty
5691                 // *plus* the fees paid for the HTLC) they don't swap `HTLC_SUCCESS_TX_WEIGHT` for
5692                 // `HTLC_TIMEOUT_TX_WEIGHT`, and vice versa.
5693                 let fee_est = TestFeeEstimator{fee_est: 253 };
5694                 let secp_ctx = Secp256k1::new();
5695                 let seed = [42; 32];
5696                 let network = Network::Testnet;
5697                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
5698
5699                 let node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
5700                 let config = UserConfig::default();
5701                 let mut chan = Channel::<EnforcingSigner>::new_outbound(&&fee_est, &&keys_provider, node_id, &InitFeatures::known(), 10000000, 100000, 42, &config).unwrap();
5702
5703                 let commitment_tx_fee_0_htlcs = chan.commit_tx_fee_msat(0);
5704                 let commitment_tx_fee_1_htlc = chan.commit_tx_fee_msat(1);
5705
5706                 // If HTLC_SUCCESS_TX_WEIGHT and HTLC_TIMEOUT_TX_WEIGHT were swapped: then this HTLC would be
5707                 // counted as dust when it shouldn't be.
5708                 let htlc_amt_above_timeout = ((253 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + chan.holder_dust_limit_satoshis + 1) * 1000;
5709                 let htlc_candidate = HTLCCandidate::new(htlc_amt_above_timeout, HTLCInitiator::LocalOffered);
5710                 let commitment_tx_fee = chan.next_local_commit_tx_fee_msat(htlc_candidate, None);
5711                 assert_eq!(commitment_tx_fee, commitment_tx_fee_1_htlc);
5712
5713                 // If swapped: this HTLC would be counted as non-dust when it shouldn't be.
5714                 let dust_htlc_amt_below_success = ((253 * HTLC_SUCCESS_TX_WEIGHT / 1000) + chan.holder_dust_limit_satoshis - 1) * 1000;
5715                 let htlc_candidate = HTLCCandidate::new(dust_htlc_amt_below_success, HTLCInitiator::RemoteOffered);
5716                 let commitment_tx_fee = chan.next_local_commit_tx_fee_msat(htlc_candidate, None);
5717                 assert_eq!(commitment_tx_fee, commitment_tx_fee_0_htlcs);
5718
5719                 chan.channel_transaction_parameters.is_outbound_from_holder = false;
5720
5721                 // If swapped: this HTLC would be counted as non-dust when it shouldn't be.
5722                 let dust_htlc_amt_above_timeout = ((253 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + chan.counterparty_dust_limit_satoshis + 1) * 1000;
5723                 let htlc_candidate = HTLCCandidate::new(dust_htlc_amt_above_timeout, HTLCInitiator::LocalOffered);
5724                 let commitment_tx_fee = chan.next_remote_commit_tx_fee_msat(htlc_candidate, None);
5725                 assert_eq!(commitment_tx_fee, commitment_tx_fee_0_htlcs);
5726
5727                 // If swapped: this HTLC would be counted as dust when it shouldn't be.
5728                 let htlc_amt_below_success = ((253 * HTLC_SUCCESS_TX_WEIGHT / 1000) + chan.counterparty_dust_limit_satoshis - 1) * 1000;
5729                 let htlc_candidate = HTLCCandidate::new(htlc_amt_below_success, HTLCInitiator::RemoteOffered);
5730                 let commitment_tx_fee = chan.next_remote_commit_tx_fee_msat(htlc_candidate, None);
5731                 assert_eq!(commitment_tx_fee, commitment_tx_fee_1_htlc);
5732         }
5733
5734         #[test]
5735         fn channel_reestablish_no_updates() {
5736                 let feeest = TestFeeEstimator{fee_est: 15000};
5737                 let logger = test_utils::TestLogger::new();
5738                 let secp_ctx = Secp256k1::new();
5739                 let seed = [42; 32];
5740                 let network = Network::Testnet;
5741                 let best_block = BestBlock::from_genesis(network);
5742                 let chain_hash = best_block.block_hash();
5743                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
5744
5745                 // Go through the flow of opening a channel between two nodes.
5746
5747                 // Create Node A's channel pointing to Node B's pubkey
5748                 let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
5749                 let config = UserConfig::default();
5750                 let mut node_a_chan = Channel::<EnforcingSigner>::new_outbound(&&feeest, &&keys_provider, node_b_node_id, &InitFeatures::known(), 10000000, 100000, 42, &config).unwrap();
5751
5752                 // Create Node B's channel by receiving Node A's open_channel message
5753                 let open_channel_msg = node_a_chan.get_open_channel(chain_hash);
5754                 let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[7; 32]).unwrap());
5755                 let mut node_b_chan = Channel::<EnforcingSigner>::new_from_req(&&feeest, &&keys_provider, node_b_node_id, &InitFeatures::known(), &open_channel_msg, 7, &config).unwrap();
5756
5757                 // Node B --> Node A: accept channel
5758                 let accept_channel_msg = node_b_chan.get_accept_channel();
5759                 node_a_chan.accept_channel(&accept_channel_msg, &config, &InitFeatures::known()).unwrap();
5760
5761                 // Node A --> Node B: funding created
5762                 let output_script = node_a_chan.get_funding_redeemscript();
5763                 let tx = Transaction { version: 1, lock_time: 0, input: Vec::new(), output: vec![TxOut {
5764                         value: 10000000, script_pubkey: output_script.clone(),
5765                 }]};
5766                 let funding_outpoint = OutPoint{ txid: tx.txid(), index: 0 };
5767                 let funding_created_msg = node_a_chan.get_outbound_funding_created(tx.clone(), funding_outpoint, &&logger).unwrap();
5768                 let (funding_signed_msg, _) = node_b_chan.funding_created(&funding_created_msg, best_block, &&logger).unwrap();
5769
5770                 // Node B --> Node A: funding signed
5771                 let _ = node_a_chan.funding_signed(&funding_signed_msg, best_block, &&logger);
5772
5773                 // Now disconnect the two nodes and check that the commitment point in
5774                 // Node B's channel_reestablish message is sane.
5775                 node_b_chan.remove_uncommitted_htlcs_and_mark_paused(&&logger);
5776                 let msg = node_b_chan.get_channel_reestablish(&&logger);
5777                 assert_eq!(msg.next_local_commitment_number, 1); // now called next_commitment_number
5778                 assert_eq!(msg.next_remote_commitment_number, 0); // now called next_revocation_number
5779                 match msg.data_loss_protect {
5780                         OptionalField::Present(DataLossProtect { your_last_per_commitment_secret, .. }) => {
5781                                 assert_eq!(your_last_per_commitment_secret, [0; 32]);
5782                         },
5783                         _ => panic!()
5784                 }
5785
5786                 // Check that the commitment point in Node A's channel_reestablish message
5787                 // is sane.
5788                 node_a_chan.remove_uncommitted_htlcs_and_mark_paused(&&logger);
5789                 let msg = node_a_chan.get_channel_reestablish(&&logger);
5790                 assert_eq!(msg.next_local_commitment_number, 1); // now called next_commitment_number
5791                 assert_eq!(msg.next_remote_commitment_number, 0); // now called next_revocation_number
5792                 match msg.data_loss_protect {
5793                         OptionalField::Present(DataLossProtect { your_last_per_commitment_secret, .. }) => {
5794                                 assert_eq!(your_last_per_commitment_secret, [0; 32]);
5795                         },
5796                         _ => panic!()
5797                 }
5798         }
5799
5800         #[test]
5801         fn channel_update() {
5802                 let feeest = TestFeeEstimator{fee_est: 15000};
5803                 let secp_ctx = Secp256k1::new();
5804                 let seed = [42; 32];
5805                 let network = Network::Testnet;
5806                 let chain_hash = genesis_block(network).header.block_hash();
5807                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
5808
5809                 // Create a channel.
5810                 let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
5811                 let config = UserConfig::default();
5812                 let mut node_a_chan = Channel::<EnforcingSigner>::new_outbound(&&feeest, &&keys_provider, node_b_node_id, &InitFeatures::known(), 10000000, 100000, 42, &config).unwrap();
5813                 assert!(node_a_chan.counterparty_forwarding_info.is_none());
5814                 assert_eq!(node_a_chan.holder_htlc_minimum_msat, 1); // the default
5815                 assert!(node_a_chan.counterparty_forwarding_info().is_none());
5816
5817                 // Make sure that receiving a channel update will update the Channel as expected.
5818                 let update = ChannelUpdate {
5819                         contents: UnsignedChannelUpdate {
5820                                 chain_hash,
5821                                 short_channel_id: 0,
5822                                 timestamp: 0,
5823                                 flags: 0,
5824                                 cltv_expiry_delta: 100,
5825                                 htlc_minimum_msat: 5,
5826                                 htlc_maximum_msat: OptionalField::Absent,
5827                                 fee_base_msat: 110,
5828                                 fee_proportional_millionths: 11,
5829                                 excess_data: Vec::new(),
5830                         },
5831                         signature: Signature::from(unsafe { FFISignature::new() })
5832                 };
5833                 node_a_chan.channel_update(&update).unwrap();
5834
5835                 // The counterparty can send an update with a higher minimum HTLC, but that shouldn't
5836                 // change our official htlc_minimum_msat.
5837                 assert_eq!(node_a_chan.holder_htlc_minimum_msat, 1);
5838                 match node_a_chan.counterparty_forwarding_info() {
5839                         Some(info) => {
5840                                 assert_eq!(info.cltv_expiry_delta, 100);
5841                                 assert_eq!(info.fee_base_msat, 110);
5842                                 assert_eq!(info.fee_proportional_millionths, 11);
5843                         },
5844                         None => panic!("expected counterparty forwarding info to be Some")
5845                 }
5846         }
5847
5848         #[test]
5849         fn outbound_commitment_test() {
5850                 // Test vectors from BOLT 3 Appendix C:
5851                 let feeest = TestFeeEstimator{fee_est: 15000};
5852                 let logger : Arc<Logger> = Arc::new(test_utils::TestLogger::new());
5853                 let secp_ctx = Secp256k1::new();
5854
5855                 let mut signer = InMemorySigner::new(
5856                         &secp_ctx,
5857                         SecretKey::from_slice(&hex::decode("30ff4956bbdd3222d44cc5e8a1261dab1e07957bdac5ae88fe3261ef321f3749").unwrap()[..]).unwrap(),
5858                         SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap(),
5859                         SecretKey::from_slice(&hex::decode("1111111111111111111111111111111111111111111111111111111111111111").unwrap()[..]).unwrap(),
5860                         SecretKey::from_slice(&hex::decode("3333333333333333333333333333333333333333333333333333333333333333").unwrap()[..]).unwrap(),
5861                         SecretKey::from_slice(&hex::decode("1111111111111111111111111111111111111111111111111111111111111111").unwrap()[..]).unwrap(),
5862
5863                         // These aren't set in the test vectors:
5864                         [0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff],
5865                         10_000_000,
5866                         [0; 32]
5867                 );
5868
5869                 assert_eq!(signer.pubkeys().funding_pubkey.serialize()[..],
5870                                 hex::decode("023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb").unwrap()[..]);
5871                 let keys_provider = Keys { signer: signer.clone() };
5872
5873                 let counterparty_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
5874                 let mut config = UserConfig::default();
5875                 config.channel_options.announced_channel = false;
5876                 let mut chan = Channel::<InMemorySigner>::new_outbound(&&feeest, &&keys_provider, counterparty_node_id, &InitFeatures::known(), 10_000_000, 100000, 42, &config).unwrap(); // Nothing uses their network key in this test
5877                 chan.holder_dust_limit_satoshis = 546;
5878                 chan.counterparty_selected_channel_reserve_satoshis = Some(0); // Filled in in accept_channel
5879
5880                 let funding_info = OutPoint{ txid: Txid::from_hex("8984484a580b825b9972d7adb15050b3ab624ccd731946b3eeddb92f4e7ef6be").unwrap(), index: 0 };
5881
5882                 let counterparty_pubkeys = ChannelPublicKeys {
5883                         funding_pubkey: public_from_secret_hex(&secp_ctx, "1552dfba4f6cf29a62a0af13c8d6981d36d0ef8d61ba10fb0fe90da7634d7e13"),
5884                         revocation_basepoint: PublicKey::from_slice(&hex::decode("02466d7fcae563e5cb09a0d1870bb580344804617879a14949cf22285f1bae3f27").unwrap()[..]).unwrap(),
5885                         payment_point: public_from_secret_hex(&secp_ctx, "4444444444444444444444444444444444444444444444444444444444444444"),
5886                         delayed_payment_basepoint: public_from_secret_hex(&secp_ctx, "1552dfba4f6cf29a62a0af13c8d6981d36d0ef8d61ba10fb0fe90da7634d7e13"),
5887                         htlc_basepoint: public_from_secret_hex(&secp_ctx, "4444444444444444444444444444444444444444444444444444444444444444")
5888                 };
5889                 chan.channel_transaction_parameters.counterparty_parameters = Some(
5890                         CounterpartyChannelTransactionParameters {
5891                                 pubkeys: counterparty_pubkeys.clone(),
5892                                 selected_contest_delay: 144
5893                         });
5894                 chan.channel_transaction_parameters.funding_outpoint = Some(funding_info);
5895                 signer.ready_channel(&chan.channel_transaction_parameters);
5896
5897                 assert_eq!(counterparty_pubkeys.payment_point.serialize()[..],
5898                            hex::decode("032c0b7cf95324a07d05398b240174dc0c2be444d96b159aa6c7f7b1e668680991").unwrap()[..]);
5899
5900                 assert_eq!(counterparty_pubkeys.funding_pubkey.serialize()[..],
5901                            hex::decode("030e9f7b623d2ccc7c9bd44d66d5ce21ce504c0acf6385a132cec6d3c39fa711c1").unwrap()[..]);
5902
5903                 assert_eq!(counterparty_pubkeys.htlc_basepoint.serialize()[..],
5904                            hex::decode("032c0b7cf95324a07d05398b240174dc0c2be444d96b159aa6c7f7b1e668680991").unwrap()[..]);
5905
5906                 // We can't just use build_holder_transaction_keys here as the per_commitment_secret is not
5907                 // derived from a commitment_seed, so instead we copy it here and call
5908                 // build_commitment_transaction.
5909                 let delayed_payment_base = &chan.holder_signer.pubkeys().delayed_payment_basepoint;
5910                 let per_commitment_secret = SecretKey::from_slice(&hex::decode("1f1e1d1c1b1a191817161514131211100f0e0d0c0b0a09080706050403020100").unwrap()[..]).unwrap();
5911                 let per_commitment_point = PublicKey::from_secret_key(&secp_ctx, &per_commitment_secret);
5912                 let htlc_basepoint = &chan.holder_signer.pubkeys().htlc_basepoint;
5913                 let keys = TxCreationKeys::derive_new(&secp_ctx, &per_commitment_point, delayed_payment_base, htlc_basepoint, &counterparty_pubkeys.revocation_basepoint, &counterparty_pubkeys.htlc_basepoint).unwrap();
5914
5915                 macro_rules! test_commitment {
5916                         ( $counterparty_sig_hex: expr, $sig_hex: expr, $tx_hex: expr, {
5917                                 $( { $htlc_idx: expr, $counterparty_htlc_sig_hex: expr, $htlc_sig_hex: expr, $htlc_tx_hex: expr } ), *
5918                         } ) => { {
5919                                 let (commitment_tx, htlcs): (_, Vec<HTLCOutputInCommitment>) = {
5920                                         let mut res = chan.build_commitment_transaction(0xffffffffffff - 42, &keys, true, false, &logger);
5921
5922                                         let htlcs = res.3.drain(..)
5923                                                 .filter_map(|(htlc, _)| if htlc.transaction_output_index.is_some() { Some(htlc) } else { None })
5924                                                 .collect();
5925                                         (res.0, htlcs)
5926                                 };
5927                                 let trusted_tx = commitment_tx.trust();
5928                                 let unsigned_tx = trusted_tx.built_transaction();
5929                                 let redeemscript = chan.get_funding_redeemscript();
5930                                 let counterparty_signature = Signature::from_der(&hex::decode($counterparty_sig_hex).unwrap()[..]).unwrap();
5931                                 let sighash = unsigned_tx.get_sighash_all(&redeemscript, chan.channel_value_satoshis);
5932                                 secp_ctx.verify(&sighash, &counterparty_signature, chan.counterparty_funding_pubkey()).unwrap();
5933
5934                                 let mut per_htlc: Vec<(HTLCOutputInCommitment, Option<Signature>)> = Vec::new();
5935                                 per_htlc.clear(); // Don't warn about excess mut for no-HTLC calls
5936                                 let mut counterparty_htlc_sigs = Vec::new();
5937                                 counterparty_htlc_sigs.clear(); // Don't warn about excess mut for no-HTLC calls
5938                                 $({
5939                                         let remote_signature = Signature::from_der(&hex::decode($counterparty_htlc_sig_hex).unwrap()[..]).unwrap();
5940                                         per_htlc.push((htlcs[$htlc_idx].clone(), Some(remote_signature)));
5941                                         counterparty_htlc_sigs.push(remote_signature);
5942                                 })*
5943                                 assert_eq!(htlcs.len(), per_htlc.len());
5944
5945                                 let holder_commitment_tx = HolderCommitmentTransaction::new(
5946                                         commitment_tx.clone(),
5947                                         counterparty_signature,
5948                                         counterparty_htlc_sigs,
5949                                         &chan.holder_signer.pubkeys().funding_pubkey,
5950                                         chan.counterparty_funding_pubkey()
5951                                 );
5952                                 let (holder_sig, htlc_sigs) = signer.sign_holder_commitment_and_htlcs(&holder_commitment_tx, &secp_ctx).unwrap();
5953                                 assert_eq!(Signature::from_der(&hex::decode($sig_hex).unwrap()[..]).unwrap(), holder_sig, "holder_sig");
5954
5955                                 let funding_redeemscript = chan.get_funding_redeemscript();
5956                                 let tx = holder_commitment_tx.add_holder_sig(&funding_redeemscript, holder_sig);
5957                                 assert_eq!(serialize(&tx)[..], hex::decode($tx_hex).unwrap()[..], "tx");
5958
5959                                 // ((htlc, counterparty_sig), (index, holder_sig))
5960                                 let mut htlc_sig_iter = holder_commitment_tx.htlcs().iter().zip(&holder_commitment_tx.counterparty_htlc_sigs).zip(htlc_sigs.iter().enumerate());
5961
5962                                 $({
5963                                         let remote_signature = Signature::from_der(&hex::decode($counterparty_htlc_sig_hex).unwrap()[..]).unwrap();
5964
5965                                         let ref htlc = htlcs[$htlc_idx];
5966                                         let htlc_tx = chan_utils::build_htlc_transaction(&unsigned_tx.txid, chan.feerate_per_kw,
5967                                                 chan.get_counterparty_selected_contest_delay().unwrap(),
5968                                                 &htlc, &keys.broadcaster_delayed_payment_key, &keys.revocation_key);
5969                                         let htlc_redeemscript = chan_utils::get_htlc_redeemscript(&htlc, &keys);
5970                                         let htlc_sighash = Message::from_slice(&bip143::SigHashCache::new(&htlc_tx).signature_hash(0, &htlc_redeemscript, htlc.amount_msat / 1000, SigHashType::All)[..]).unwrap();
5971                                         secp_ctx.verify(&htlc_sighash, &remote_signature, &keys.countersignatory_htlc_key).unwrap();
5972
5973                                         let mut preimage: Option<PaymentPreimage> = None;
5974                                         if !htlc.offered {
5975                                                 for i in 0..5 {
5976                                                         let out = PaymentHash(Sha256::hash(&[i; 32]).into_inner());
5977                                                         if out == htlc.payment_hash {
5978                                                                 preimage = Some(PaymentPreimage([i; 32]));
5979                                                         }
5980                                                 }
5981
5982                                                 assert!(preimage.is_some());
5983                                         }
5984
5985                                         let htlc_sig = htlc_sig_iter.next().unwrap();
5986                                         assert_eq!((htlc_sig.0).0.transaction_output_index, Some($htlc_idx), "output index");
5987
5988                                         let signature = Signature::from_der(&hex::decode($htlc_sig_hex).unwrap()[..]).unwrap();
5989                                         assert_eq!(signature, *(htlc_sig.1).1, "htlc sig");
5990                                         let index = (htlc_sig.1).0;
5991                                         let channel_parameters = chan.channel_transaction_parameters.as_holder_broadcastable();
5992                                         let trusted_tx = holder_commitment_tx.trust();
5993                                         assert_eq!(serialize(&trusted_tx.get_signed_htlc_tx(&channel_parameters, index, &(htlc_sig.0).1, (htlc_sig.1).1, &preimage))[..],
5994                                                         hex::decode($htlc_tx_hex).unwrap()[..], "htlc tx");
5995                                 })*
5996                                 assert!(htlc_sig_iter.next().is_none());
5997                         } }
5998                 }
5999
6000                 // simple commitment tx with no HTLCs
6001                 chan.value_to_self_msat = 7000000000;
6002
6003                 test_commitment!("3045022100c3127b33dcc741dd6b05b1e63cbd1a9a7d816f37af9b6756fa2376b056f032370220408b96279808fe57eb7e463710804cdf4f108388bc5cf722d8c848d2c7f9f3b0",
6004                                                  "30440220616210b2cc4d3afb601013c373bbd8aac54febd9f15400379a8cb65ce7deca60022034236c010991beb7ff770510561ae8dc885b8d38d1947248c38f2ae055647142",
6005                                                  "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", {});
6006
6007                 chan.pending_inbound_htlcs.push({
6008                         let mut out = InboundHTLCOutput{
6009                                 htlc_id: 0,
6010                                 amount_msat: 1000000,
6011                                 cltv_expiry: 500,
6012                                 payment_hash: PaymentHash([0; 32]),
6013                                 state: InboundHTLCState::Committed,
6014                         };
6015                         out.payment_hash.0 = Sha256::hash(&hex::decode("0000000000000000000000000000000000000000000000000000000000000000").unwrap()).into_inner();
6016                         out
6017                 });
6018                 chan.pending_inbound_htlcs.push({
6019                         let mut out = InboundHTLCOutput{
6020                                 htlc_id: 1,
6021                                 amount_msat: 2000000,
6022                                 cltv_expiry: 501,
6023                                 payment_hash: PaymentHash([0; 32]),
6024                                 state: InboundHTLCState::Committed,
6025                         };
6026                         out.payment_hash.0 = Sha256::hash(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()).into_inner();
6027                         out
6028                 });
6029                 chan.pending_outbound_htlcs.push({
6030                         let mut out = OutboundHTLCOutput{
6031                                 htlc_id: 2,
6032                                 amount_msat: 2000000,
6033                                 cltv_expiry: 502,
6034                                 payment_hash: PaymentHash([0; 32]),
6035                                 state: OutboundHTLCState::Committed,
6036                                 source: HTLCSource::dummy(),
6037                         };
6038                         out.payment_hash.0 = Sha256::hash(&hex::decode("0202020202020202020202020202020202020202020202020202020202020202").unwrap()).into_inner();
6039                         out
6040                 });
6041                 chan.pending_outbound_htlcs.push({
6042                         let mut out = OutboundHTLCOutput{
6043                                 htlc_id: 3,
6044                                 amount_msat: 3000000,
6045                                 cltv_expiry: 503,
6046                                 payment_hash: PaymentHash([0; 32]),
6047                                 state: OutboundHTLCState::Committed,
6048                                 source: HTLCSource::dummy(),
6049                         };
6050                         out.payment_hash.0 = Sha256::hash(&hex::decode("0303030303030303030303030303030303030303030303030303030303030303").unwrap()).into_inner();
6051                         out
6052                 });
6053                 chan.pending_inbound_htlcs.push({
6054                         let mut out = InboundHTLCOutput{
6055                                 htlc_id: 4,
6056                                 amount_msat: 4000000,
6057                                 cltv_expiry: 504,
6058                                 payment_hash: PaymentHash([0; 32]),
6059                                 state: InboundHTLCState::Committed,
6060                         };
6061                         out.payment_hash.0 = Sha256::hash(&hex::decode("0404040404040404040404040404040404040404040404040404040404040404").unwrap()).into_inner();
6062                         out
6063                 });
6064
6065                 // commitment tx with all five HTLCs untrimmed (minimum feerate)
6066                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6067                 chan.feerate_per_kw = 0;
6068
6069                 test_commitment!("3044022009b048187705a8cbc9ad73adbe5af148c3d012e1f067961486c822c7af08158c022006d66f3704cfab3eb2dc49dae24e4aa22a6910fc9b424007583204e3621af2e5",
6070                                  "304402206fc2d1f10ea59951eefac0b4b7c396a3c3d87b71ff0b019796ef4535beaf36f902201765b0181e514d04f4c8ad75659d7037be26cdb3f8bb6f78fe61decef484c3ea",
6071                                  "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", {
6072
6073                                   { 0,
6074                                   "3045022100d9e29616b8f3959f1d3d7f7ce893ffedcdc407717d0de8e37d808c91d3a7c50d022078c3033f6d00095c8720a4bc943c1b45727818c082e4e3ddbc6d3116435b624b",
6075                                   "30440220636de5682ef0c5b61f124ec74e8aa2461a69777521d6998295dcea36bc3338110220165285594b23c50b28b82df200234566628a27bcd17f7f14404bd865354eb3ce",
6076                                   "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" },
6077
6078                                   { 1,
6079                                   "30440220649fe8b20e67e46cbb0d09b4acea87dbec001b39b08dee7bdd0b1f03922a8640022037c462dff79df501cecfdb12ea7f4de91f99230bb544726f6e04527b1f896004",
6080                                   "3045022100803159dee7935dba4a1d36a61055ce8fd62caa528573cc221ae288515405a252022029c59e7cffce374fe860100a4a63787e105c3cf5156d40b12dd53ff55ac8cf3f",
6081                                   "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" },
6082
6083                                   { 2,
6084                                   "30440220770fc321e97a19f38985f2e7732dd9fe08d16a2efa4bcbc0429400a447faf49102204d40b417f3113e1b0944ae0986f517564ab4acd3d190503faf97a6e420d43352",
6085                                   "3045022100a437cc2ce77400ecde441b3398fea3c3ad8bdad8132be818227fe3c5b8345989022069d45e7fa0ae551ec37240845e2c561ceb2567eacf3076a6a43a502d05865faa",
6086                                   "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" },
6087
6088                                   { 3,
6089                                   "304402207bcbf4f60a9829b05d2dbab84ed593e0291836be715dc7db6b72a64caf646af802201e489a5a84f7c5cc130398b841d138d031a5137ac8f4c49c770a4959dc3c1363",
6090                                   "304402203121d9b9c055f354304b016a36662ee99e1110d9501cb271b087ddb6f382c2c80220549882f3f3b78d9c492de47543cb9a697cecc493174726146536c5954dac7487",
6091                                   "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" },
6092
6093                                   { 4,
6094                                   "3044022076dca5cb81ba7e466e349b7128cdba216d4d01659e29b96025b9524aaf0d1899022060de85697b88b21c749702b7d2cfa7dfeaa1f472c8f1d7d9c23f2bf968464b87",
6095                                   "3045022100d9080f103cc92bac15ec42464a95f070c7fb6925014e673ee2ea1374d36a7f7502200c65294d22eb20d48564954d5afe04a385551919d8b2ddb4ae2459daaeee1d95",
6096                                   "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" }
6097                 } );
6098
6099                 // commitment tx with seven outputs untrimmed (maximum feerate)
6100                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6101                 chan.feerate_per_kw = 647;
6102
6103                 test_commitment!("3045022100a135f9e8a5ed25f7277446c67956b00ce6f610ead2bdec2c2f686155b7814772022059f1f6e1a8b336a68efcc1af3fe4d422d4827332b5b067501b099c47b7b5b5ee",
6104                                  "30450221009ec15c687898bb4da8b3a833e5ab8bfc51ec6e9202aaa8e66611edfd4a85ed1102203d7183e45078b9735c93450bc3415d3e5a8c576141a711ec6ddcb4a893926bb7",
6105                                  "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", {
6106
6107                                   { 0,
6108                                   "30450221008437627f9ad84ac67052e2a414a4367b8556fd1f94d8b02590f89f50525cd33502205b9c21ff6e7fc864f2352746ad8ba59182510819acb644e25b8a12fc37bbf24f",
6109                                   "30440220344b0deb055230d01703e6c7acd45853c4af2328b49b5d8af4f88a060733406602202ea64f2a43d5751edfe75503cbc35a62e3141b5ed032fa03360faf4ca66f670b",
6110                                   "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" },
6111
6112                                   { 1,
6113                                   "304402205a67f92bf6845cf2892b48d874ac1daf88a36495cf8a06f93d83180d930a6f75022031da1621d95c3f335cc06a3056cf960199dae600b7cf89088f65fc53cdbef28c",
6114                                   "30450221009e5e3822b0185c6799a95288c597b671d6cc69ab80f43740f00c6c3d0752bdda02206da947a74bd98f3175324dc56fdba86cc783703a120a6f0297537e60632f4c7f",
6115                                   "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" },
6116
6117                                   { 2,
6118                                   "30440220437e21766054a3eef7f65690c5bcfa9920babbc5af92b819f772f6ea96df6c7402207173622024bd97328cfb26c6665e25c2f5d67c319443ccdc60c903217005d8c8",
6119                                   "3045022100fcfc47e36b712624677626cef3dc1d67f6583bd46926a6398fe6b00b0c9a37760220525788257b187fc775c6370d04eadf34d06f3650a63f8df851cee0ecb47a1673",
6120                                   "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" },
6121
6122                                   { 3,
6123                                   "304402207436e10737e4df499fc051686d3e11a5bb2310e4d1f1e691d287cef66514791202207cb58e71a6b7a42dd001b7e3ae672ea4f71ea3e1cd412b742e9124abb0739c64",
6124                                   "3045022100e78211b8409afb7255ffe37337da87f38646f1faebbdd61bc1920d69e3ead67a02201a626305adfcd16bfb7e9340928d9b6305464eab4aa4c4a3af6646e9b9f69dee",
6125                                   "020000000001012cfb3e4788c206881d38f2996b6cb2109b5935acb527d14bdaa7b908afa9b2fe030000000000000000010c0a0000000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e050047304402207436e10737e4df499fc051686d3e11a5bb2310e4d1f1e691d287cef66514791202207cb58e71a6b7a42dd001b7e3ae672ea4f71ea3e1cd412b742e9124abb0739c6401483045022100e78211b8409afb7255ffe37337da87f38646f1faebbdd61bc1920d69e3ead67a02201a626305adfcd16bfb7e9340928d9b6305464eab4aa4c4a3af6646e9b9f69dee01008576a91414011f7254d96b819c76986c277d115efce6f7b58763ac67210394854aa6eab5b2a8122cc726e9dded053a2184d88256816826d6231c068d4a5b7c820120876475527c21030d417a46946384f88d5f3337267c5e579765875dc4daca813e21734b140639e752ae67a9148a486ff2e31d6158bf39e2608864d63fefd09d5b88ac6868f7010000" },
6126
6127                                   { 4,
6128                                   "30450221009acd6a827a76bfee50806178dfe0495cd4e1d9c58279c194c7b01520fe68cb8d022024d439047c368883e570997a7d40f0b430cb5a742f507965e7d3063ae3feccca",
6129                                   "3044022048762cf546bbfe474f1536365ea7c416e3c0389d60558bc9412cb148fb6ab68202207215d7083b75c96ff9d2b08c59c34e287b66820f530b486a9aa4cdd9c347d5b9",
6130                                   "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" }
6131                 } );
6132
6133                 // commitment tx with six outputs untrimmed (minimum feerate)
6134                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6135                 chan.feerate_per_kw = 648;
6136
6137                 test_commitment!("304402203948f900a5506b8de36a4d8502f94f21dd84fd9c2314ab427d52feaa7a0a19f2022059b6a37a4adaa2c5419dc8aea63c6e2a2ec4c4bde46207f6dc1fcd22152fc6e5",
6138                                  "3045022100b15f72908ba3382a34ca5b32519240a22300cc6015b6f9418635fb41f3d01d8802207adb331b9ed1575383dca0f2355e86c173802feecf8298fbea53b9d4610583e9",
6139                                  "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", {
6140
6141                                   { 0,
6142                                   "3045022100a031202f3be94678f0e998622ee95ebb6ada8da1e9a5110228b5e04a747351e4022010ca6a21e18314ed53cfaae3b1f51998552a61a468e596368829a50ce40110e0",
6143                                   "304502210097e1873b57267730154595187a34949d3744f52933070c74757005e61ce2112e02204ecfba2aa42d4f14bdf8bad4206bb97217b702e6c433e0e1b0ce6587e6d46ec6",
6144                                   "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" },
6145
6146                                   { 1,
6147                                   "304402202361012a634aee7835c5ecdd6413dcffa8f404b7e77364c792cff984e4ee71e90220715c5e90baa08daa45a7439b1ee4fa4843ed77b19c058240b69406606d384124",
6148                                   "3044022019de73b00f1d818fb388e83b2c8c31f6bce35ac624e215bc12f88f9dc33edf48022006ff814bb9f700ee6abc3294e146fac3efd4f13f0005236b41c0a946ee00c9ae",
6149                                   "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" },
6150
6151                                   { 2,
6152                                   "304402207e8e82cd71ed4febeb593732c260456836e97d81896153ecd2b3cf320ca6861702202dd4a30f68f98ced7cc56a36369ac1fdd978248c5ff4ed204fc00cc625532989",
6153                                   "3045022100bd0be6100c4fd8f102ec220e1b053e4c4e2ecca25615490150007b40d314dc3902201a1e0ea266965b43164d9e6576f58fa6726d42883dd1c3996d2925c2e2260796",
6154                                   "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" },
6155
6156                                   { 3,
6157                                   "3044022024cd52e4198c8ae0e414a86d86b5a65ea7450f2eb4e783096736d93395eca5ce022078f0094745b45be4d4b2b04dd5978c9e66ba49109e5704403e84aaf5f387d6be",
6158                                   "3045022100bbfb9d0a946d420807c86e985d636cceb16e71c3694ed186316251a00cbd807202207773223f9a337e145f64673825be9b30d07ef1542c82188b264bedcf7cda78c6",
6159                                   "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" }
6160                 } );
6161
6162                 // commitment tx with six outputs untrimmed (maximum feerate)
6163                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6164                 chan.feerate_per_kw = 2069;
6165
6166                 test_commitment!("304502210090b96a2498ce0c0f2fadbec2aab278fed54c1a7838df793ec4d2c78d96ec096202204fdd439c50f90d483baa7b68feeef4bd33bc277695405447bcd0bfb2ca34d7bc",
6167                                  "3045022100ad9a9bbbb75d506ca3b716b336ee3cf975dd7834fcf129d7dd188146eb58a8b4022061a759ee417339f7fe2ea1e8deb83abb6a74db31a09b7648a932a639cda23e33",
6168                                  "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", {
6169
6170                                   { 0,
6171                                   "3045022100f33513ee38abf1c582876f921f8fddc06acff48e04515532a32d3938de938ffd02203aa308a2c1863b7d6fdf53159a1465bf2e115c13152546cc5d74483ceaa7f699",
6172                                   "3045022100a637902a5d4c9ba9e7c472a225337d5aac9e2e3f6744f76e237132e7619ba0400220035c60d784a031c0d9f6df66b7eab8726a5c25397399ee4aa960842059eb3f9d",
6173                                   "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" },
6174
6175                                   { 1,
6176                                   "3045022100ce07682cf4b90093c22dc2d9ab2a77ad6803526b655ef857221cc96af5c9e0bf02200f501cee22e7a268af40b555d15a8237c9f36ad67ef1841daf9f6a0267b1e6df",
6177                                   "3045022100e57e46234f8782d3ff7aa593b4f7446fb5316c842e693dc63ee324fd49f6a1c302204a2f7b44c48bd26e1554422afae13153eb94b29d3687b733d18930615fb2db61",
6178                                   "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" },
6179
6180                                   { 2,
6181                                   "3045022100e3e35492e55f82ec0bc2f317ffd7a486d1f7024330fe9743c3559fc39f32ef0c02203d1d4db651fc388a91d5ad8ecdd8e83673063bc8eefe27cfd8c189090e3a23e0",
6182                                   "3044022068613fb1b98eb3aec7f44c5b115b12343c2f066c4277c82b5f873dfe68f37f50022028109b4650f3f528ca4bfe9a467aff2e3e43893b61b5159157119d5d95cf1c18",
6183                                   "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" },
6184
6185                                   { 3,
6186                                   "304402207475aeb0212ef9bf5130b60937817ad88c9a87976988ef1f323f026148cc4a850220739fea17ad3257dcad72e509c73eebe86bee30b178467b9fdab213d631b109df",
6187                                   "3045022100d315522e09e7d53d2a659a79cb67fef56d6c4bddf3f46df6772d0d20a7beb7c8022070bcc17e288607b6a72be0bd83368bb6d53488db266c1cdb4d72214e4f02ac33",
6188                                   "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" }
6189                 } );
6190
6191                 // commitment tx with five outputs untrimmed (minimum feerate)
6192                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6193                 chan.feerate_per_kw = 2070;
6194
6195                 test_commitment!("304402204ca1ba260dee913d318271d86e10ca0f5883026fb5653155cff600fb40895223022037b145204b7054a40e08bb1fefbd826f827b40838d3e501423bcc57924bcb50c",
6196                                  "3044022001014419b5ba00e083ac4e0a85f19afc848aacac2d483b4b525d15e2ae5adbfe022015ebddad6ee1e72b47cb09f3e78459da5be01ccccd95dceca0e056a00cc773c1",
6197                                  "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", {
6198
6199                                   { 0,
6200                                   "304402205f6b6d12d8d2529fb24f4445630566cf4abbd0f9330ab6c2bdb94222d6a2a0c502202f556258ae6f05b193749e4c541dfcc13b525a5422f6291f073f15617ba8579b",
6201                                   "30440220150b11069454da70caf2492ded9e0065c9a57f25ac2a4c52657b1d15b6c6ed85022068a38833b603c8892717206383611bad210f1cbb4b1f87ea29c6c65b9e1cb3e5",
6202                                   "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" },
6203
6204                                   { 1,
6205                                   "3045022100f960dfb1c9aee7ce1437efa65b523e399383e8149790e05d8fed27ff6e42fe0002202fe8613e062ffe0b0c518cc4101fba1c6de70f64a5bcc7ae663f2efae43b8546",
6206                                   "30450221009a6ed18e6873bc3644332a6ee21c152a5b102821865350df7a8c74451a51f9f2022050d801fb4895d7d7fbf452824c0168347f5c0cbe821cf6a97a63af5b8b2563c6",
6207                                   "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" },
6208
6209                                   { 2,
6210                                   "3045022100ae5fc7717ae684bc1fcf9020854e5dbe9842c9e7472879ac06ff95ac2bb10e4e022057728ada4c00083a3e65493fb5d50a232165948a1a0f530ef63185c2c8c56504",
6211                                   "30440220408ad3009827a8fccf774cb285587686bfb2ed041f89a89453c311ce9c8ee0f902203c7392d9f8306d3a46522a66bd2723a7eb2628cb2d9b34d4c104f1766bf37502",
6212                                   "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" }
6213                 } );
6214
6215                 // commitment tx with five outputs untrimmed (maximum feerate)
6216                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6217                 chan.feerate_per_kw = 2194;
6218
6219                 test_commitment!("304402204bb3d6e279d71d9da414c82de42f1f954267c762b2e2eb8b76bc3be4ea07d4b0022014febc009c5edc8c3fc5d94015de163200f780046f1c293bfed8568f08b70fb3",
6220                                  "3044022072c2e2b1c899b2242656a537dde2892fa3801be0d6df0a87836c550137acde8302201654aa1974d37a829083c3ba15088689f30b56d6a4f6cb14c7bad0ee3116d398",
6221                                  "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", {
6222
6223                                   { 0,
6224                                   "3045022100939726680351a7856c1bc386d4a1f422c7d29bd7b56afc139570f508474e6c40022023175a799ccf44c017fbaadb924c40b2a12115a5b7d0dfd3228df803a2de8450",
6225                                   "304502210099c98c2edeeee6ec0fb5f3bea8b79bb016a2717afa9b5072370f34382de281d302206f5e2980a995e045cf90a547f0752a7ee99d48547bc135258fe7bc07e0154301",
6226                                   "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" },
6227
6228                                   { 1,
6229                                   "3044022021bb883bf324553d085ba2e821cad80c28ef8b303dbead8f98e548783c02d1600220638f9ef2a9bba25869afc923f4b5dc38be3bb459f9efa5d869392d5f7779a4a0",
6230                                   "3045022100fd85bd7697b89c08ec12acc8ba89b23090637d83abd26ca37e01ae93e67c367302202b551fe69386116c47f984aab9c8dfd25d864dcde5d3389cfbef2447a85c4b77",
6231                                   "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" },
6232
6233                                   { 2,
6234                                   "3045022100c9e6f0454aa598b905a35e641a70cc9f67b5f38cc4b00843a041238c4a9f1c4a0220260a2822a62da97e44583e837245995ca2e36781769c52f19e498efbdcca262b",
6235                                   "30450221008a9f2ea24cd455c2b64c1472a5fa83865b0a5f49a62b661801e884cf2849af8302204d44180e50bf6adfcf1c1e581d75af91aba4e28681ce4a5ee5f3cbf65eca10f3",
6236                                   "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" }
6237                 } );
6238
6239                 // commitment tx with four outputs untrimmed (minimum feerate)
6240                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6241                 chan.feerate_per_kw = 2195;
6242
6243                 test_commitment!("304402201a8c1b1f9671cd9e46c7323a104d7047cc48d3ee80d40d4512e0c72b8dc65666022066d7f9a2ce18c9eb22d2739ffcce05721c767f9b607622a31b6ea5793ddce403",
6244                                  "3044022044d592025b610c0d678f65032e87035cdfe89d1598c522cc32524ae8172417c30220749fef9d5b2ae8cdd91ece442ba8809bc891efedae2291e578475f97715d1767",
6245                                  "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", {
6246
6247                                   { 0,
6248                                   "3045022100e57b845066a06ee7c2cbfc29eabffe52daa9bf6f6de760066d04df9f9b250e0002202ffb197f0e6e0a77a75a9aff27014bd3de83b7f748d7efef986abe655e1dd50e",
6249                                   "3045022100ecc8c6529d0b2316d046f0f0757c1e1c25a636db168ec4f3aa1b9278df685dc0022067ae6b65e936f1337091f7b18a15935b608c5f2cdddb2f892ed0babfdd376d76",
6250                                   "020000000001018130a10f09b13677ba2885a8bca32860f3a952e5912b829a473639b5a2c07b900000000000000000000109060000000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e0500483045022100e57b845066a06ee7c2cbfc29eabffe52daa9bf6f6de760066d04df9f9b250e0002202ffb197f0e6e0a77a75a9aff27014bd3de83b7f748d7efef986abe655e1dd50e01483045022100ecc8c6529d0b2316d046f0f0757c1e1c25a636db168ec4f3aa1b9278df685dc0022067ae6b65e936f1337091f7b18a15935b608c5f2cdddb2f892ed0babfdd376d7601008576a91414011f7254d96b819c76986c277d115efce6f7b58763ac67210394854aa6eab5b2a8122cc726e9dded053a2184d88256816826d6231c068d4a5b7c820120876475527c21030d417a46946384f88d5f3337267c5e579765875dc4daca813e21734b140639e752ae67a9148a486ff2e31d6158bf39e2608864d63fefd09d5b88ac6868f7010000" },
6251
6252                                   { 1,
6253                                   "3045022100d193b7ecccad8057571620a0b1ffa6c48e9483311723b59cf536043b20bc51550220546d4bd37b3b101ecda14f6c907af46ec391abce1cd9c7ce22b1a62b534f2f2a",
6254                                   "3044022014d66f11f9cacf923807eba49542076c5fe5cccf252fb08fe98c78ef3ca6ab5402201b290dbe043cc512d9d78de074a5a129b8759bc6a6c546b190d120b690bd6e82",
6255                                   "020000000001018130a10f09b13677ba2885a8bca32860f3a952e5912b829a473639b5a2c07b900100000000000000000199090000000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e0500483045022100d193b7ecccad8057571620a0b1ffa6c48e9483311723b59cf536043b20bc51550220546d4bd37b3b101ecda14f6c907af46ec391abce1cd9c7ce22b1a62b534f2f2a01473044022014d66f11f9cacf923807eba49542076c5fe5cccf252fb08fe98c78ef3ca6ab5402201b290dbe043cc512d9d78de074a5a129b8759bc6a6c546b190d120b690bd6e82012004040404040404040404040404040404040404040404040404040404040404048a76a91414011f7254d96b819c76986c277d115efce6f7b58763ac67210394854aa6eab5b2a8122cc726e9dded053a2184d88256816826d6231c068d4a5b7c8201208763a91418bc1a114ccf9c052d3d23e28d3b0a9d1227434288527c21030d417a46946384f88d5f3337267c5e579765875dc4daca813e21734b140639e752ae677502f801b175ac686800000000" }
6256                 } );
6257
6258                 // commitment tx with four outputs untrimmed (maximum feerate)
6259                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6260                 chan.feerate_per_kw = 3702;
6261
6262                 test_commitment!("304502210092a587aeb777f869e7ff0d7898ea619ee26a3dacd1f3672b945eea600be431100220077ee9eae3528d15251f2a52b607b189820e57a6ccfac8d1af502b132ee40169",
6263                                  "3045022100e5efb73c32d32da2d79702299b6317de6fb24a60476e3855926d78484dd1b3c802203557cb66a42c944ef06e00bcc4da35a5bcb2f185aab0f8e403e519e1d66aaf75",
6264                                  "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", {
6265
6266                                   { 0,
6267                                   "304402206fa54c11f98c3bae1e93df43fc7affeb05b476bf8060c03e29c377c69bc08e8b0220672701cce50d5c379ff45a5d2cfe48ac44973adb066ac32608e21221d869bb89",
6268                                   "304402206e36c683ebf2cb16bcef3d5439cf8b53cd97280a365ed8acd7abb85a8ba5f21c02206e8621edfc2a5766cbc96eb67fd501127ff163eb6b85518a39f7d4974aef126f",
6269                                   "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" },
6270
6271                                   { 1,
6272                                   "3044022057649739b0eb74d541ead0dfdb3d4b2c15aa192720031044c3434c67812e5ca902201e5ede42d960ae551707f4a6b34b09393cf4dee2418507daa022e3550dbb5817",
6273                                   "304402207faad26678c8850e01b4a0696d60841f7305e1832b786110ee9075cb92ed14a30220516ef8ee5dfa80824ea28cbcec0dd95f8b847146257c16960db98507db15ffdc",
6274                                   "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" }
6275                 } );
6276
6277                 // commitment tx with three outputs untrimmed (minimum feerate)
6278                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6279                 chan.feerate_per_kw = 3703;
6280
6281                 test_commitment!("3045022100b495d239772a237ff2cf354b1b11be152fd852704cb184e7356d13f2fb1e5e430220723db5cdb9cbd6ead7bfd3deb419cf41053a932418cbb22a67b581f40bc1f13e",
6282                                  "304402201b736d1773a124c745586217a75bed5f66c05716fbe8c7db4fdb3c3069741cdd02205083f39c321c1bcadfc8d97e3c791a66273d936abac0c6a2fde2ed46019508e1",
6283                                  "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", {
6284
6285                                   { 0,
6286                                   "3045022100c34c61735f93f2e324cc873c3b248111ccf8f6db15d5969583757010d4ad2b4602207867bb919b2ddd6387873e425345c9b7fd18d1d66aba41f3607bc2896ef3c30a",
6287                                   "3045022100988c143e2110067117d2321bdd4bd16ca1734c98b29290d129384af0962b634e02206c1b02478878c5f547018b833986578f90c3e9be669fe5788ad0072a55acbb05",
6288                                   "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" }
6289                 } );
6290
6291                 // commitment tx with three outputs untrimmed (maximum feerate)
6292                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6293                 chan.feerate_per_kw = 4914;
6294
6295                 test_commitment!("3045022100b4b16d5f8cc9fc4c1aff48831e832a0d8990e133978a66e302c133550954a44d022073573ce127e2200d316f6b612803a5c0c97b8d20e1e44dbe2ac0dd2fb8c95244",
6296                                  "3045022100d72638bc6308b88bb6d45861aae83e5b9ff6e10986546e13bce769c70036e2620220320be7c6d66d22f30b9fcd52af66531505b1310ca3b848c19285b38d8a1a8c19",
6297                                  "02000000000101bef67e4e2fb9ddeeb3461973cd4c62abb35050b1add772995b820b584a488489000000000038b02b8003a00f0000000000002200208c48d15160397c9731df9bc3b236656efb6665fbfe92b4a6878e88a499f741c4c0c62d0000000000160014cc1b07838e387deacd0e5232e1e8b49f4c29e484ae8f6a00000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e0400483045022100d72638bc6308b88bb6d45861aae83e5b9ff6e10986546e13bce769c70036e2620220320be7c6d66d22f30b9fcd52af66531505b1310ca3b848c19285b38d8a1a8c1901483045022100b4b16d5f8cc9fc4c1aff48831e832a0d8990e133978a66e302c133550954a44d022073573ce127e2200d316f6b612803a5c0c97b8d20e1e44dbe2ac0dd2fb8c9524401475221023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb21030e9f7b623d2ccc7c9bd44d66d5ce21ce504c0acf6385a132cec6d3c39fa711c152ae3e195220", {
6298
6299                                   { 0,
6300                                   "3045022100f43591c156038ba217756006bb3c55f7d113a325cdd7d9303c82115372858d68022016355b5aadf222bc8d12e426c75f4a03423917b2443a103eb2a498a3a2234374",
6301                                   "30440220585dee80fafa264beac535c3c0bb5838ac348b156fdc982f86adc08dfc9bfd250220130abb82f9f295cc9ef423dcfef772fde2acd85d9df48cc538981d26a10a9c10",
6302                                   "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" }
6303                 } );
6304
6305                 // commitment tx with two outputs untrimmed (minimum feerate)
6306                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6307                 chan.feerate_per_kw = 4915;
6308
6309                 test_commitment!("304402203a286936e74870ca1459c700c71202af0381910a6bfab687ef494ef1bc3e02c902202506c362d0e3bee15e802aa729bf378e051644648253513f1c085b264cc2a720",
6310                                  "30450221008a953551f4d67cb4df3037207fc082ddaf6be84d417b0bd14c80aab66f1b01a402207508796dc75034b2dee876fe01dc05a08b019f3e5d689ac8842ade2f1befccf5",
6311                                  "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", {});
6312
6313                 // commitment tx with two outputs untrimmed (maximum feerate)
6314                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6315                 chan.feerate_per_kw = 9651180;
6316
6317                 test_commitment!("304402200a8544eba1d216f5c5e530597665fa9bec56943c0f66d98fc3d028df52d84f7002201e45fa5c6bc3a506cc2553e7d1c0043a9811313fc39c954692c0d47cfce2bbd3",
6318                                  "3045022100e11b638c05c650c2f63a421d36ef8756c5ce82f2184278643520311cdf50aa200220259565fb9c8e4a87ccaf17f27a3b9ca4f20625754a0920d9c6c239d8156a11de",
6319                                  "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", {});
6320
6321                 // commitment tx with one output untrimmed (minimum feerate)
6322                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6323                 chan.feerate_per_kw = 9651181;
6324
6325                 test_commitment!("304402202ade0142008309eb376736575ad58d03e5b115499709c6db0b46e36ff394b492022037b63d78d66404d6504d4c4ac13be346f3d1802928a6d3ad95a6a944227161a2",
6326                                  "304402207e8d51e0c570a5868a78414f4e0cbfaed1106b171b9581542c30718ee4eb95ba02203af84194c97adf98898c9afe2f2ed4a7f8dba05a2dfab28ac9d9c604aa49a379",
6327                                  "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", {});
6328
6329                 // commitment tx with fee greater than funder amount
6330                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6331                 chan.feerate_per_kw = 9651936;
6332
6333                 test_commitment!("304402202ade0142008309eb376736575ad58d03e5b115499709c6db0b46e36ff394b492022037b63d78d66404d6504d4c4ac13be346f3d1802928a6d3ad95a6a944227161a2",
6334                                  "304402207e8d51e0c570a5868a78414f4e0cbfaed1106b171b9581542c30718ee4eb95ba02203af84194c97adf98898c9afe2f2ed4a7f8dba05a2dfab28ac9d9c604aa49a379",
6335                                  "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", {});
6336
6337                 // commitment tx with 3 htlc outputs, 2 offered having the same amount and preimage
6338                 chan.value_to_self_msat = 7_000_000_000 - 2_000_000;
6339                 chan.feerate_per_kw = 253;
6340                 chan.pending_inbound_htlcs.clear();
6341                 chan.pending_inbound_htlcs.push({
6342                         let mut out = InboundHTLCOutput{
6343                                 htlc_id: 1,
6344                                 amount_msat: 2000000,
6345                                 cltv_expiry: 501,
6346                                 payment_hash: PaymentHash([0; 32]),
6347                                 state: InboundHTLCState::Committed,
6348                         };
6349                         out.payment_hash.0 = Sha256::hash(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()).into_inner();
6350                         out
6351                 });
6352                 chan.pending_outbound_htlcs.clear();
6353                 chan.pending_outbound_htlcs.push({
6354                         let mut out = OutboundHTLCOutput{
6355                                 htlc_id: 6,
6356                                 amount_msat: 5000000,
6357                                 cltv_expiry: 506,
6358                                 payment_hash: PaymentHash([0; 32]),
6359                                 state: OutboundHTLCState::Committed,
6360                                 source: HTLCSource::dummy(),
6361                         };
6362                         out.payment_hash.0 = Sha256::hash(&hex::decode("0505050505050505050505050505050505050505050505050505050505050505").unwrap()).into_inner();
6363                         out
6364                 });
6365                 chan.pending_outbound_htlcs.push({
6366                         let mut out = OutboundHTLCOutput{
6367                                 htlc_id: 5,
6368                                 amount_msat: 5000000,
6369                                 cltv_expiry: 505,
6370                                 payment_hash: PaymentHash([0; 32]),
6371                                 state: OutboundHTLCState::Committed,
6372                                 source: HTLCSource::dummy(),
6373                         };
6374                         out.payment_hash.0 = Sha256::hash(&hex::decode("0505050505050505050505050505050505050505050505050505050505050505").unwrap()).into_inner();
6375                         out
6376                 });
6377
6378                 test_commitment!("30440220048705bec5288d28b3f29344b8d124853b1af423a568664d2c6f02c8ea886525022060f998a461052a2476b912db426ea2a06700953a241135c7957f2e79bc222df9",
6379                                  "3045022100c4f1d60b6fca9febc8b39de1a31e84c5f7c4b41c97239ef05f4350aa484c6b5e02200c5134ac8b20eb7a29d0dd4a501f6aa8fefb8489171f4cb408bd2a32324ab03f",
6380                                  "02000000000101bef67e4e2fb9ddeeb3461973cd4c62abb35050b1add772995b820b584a488489000000000038b02b8005d007000000000000220020748eba944fedc8827f6b06bc44678f93c0f9e6078b35c6331ed31e75f8ce0c2d8813000000000000220020305c12e1a0bc21e283c131cea1c66d68857d28b7b2fce0a6fbc40c164852121b8813000000000000220020305c12e1a0bc21e283c131cea1c66d68857d28b7b2fce0a6fbc40c164852121bc0c62d0000000000160014cc1b07838e387deacd0e5232e1e8b49f4c29e484a79f6a00000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e0400483045022100c4f1d60b6fca9febc8b39de1a31e84c5f7c4b41c97239ef05f4350aa484c6b5e02200c5134ac8b20eb7a29d0dd4a501f6aa8fefb8489171f4cb408bd2a32324ab03f014730440220048705bec5288d28b3f29344b8d124853b1af423a568664d2c6f02c8ea886525022060f998a461052a2476b912db426ea2a06700953a241135c7957f2e79bc222df901475221023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb21030e9f7b623d2ccc7c9bd44d66d5ce21ce504c0acf6385a132cec6d3c39fa711c152ae3e195220", {
6381
6382                                   { 0,
6383                                   "304502210081cbb94121761d34c189cd4e6a281feea6f585060ad0ba2632e8d6b3c6bb8a6c02201007981bbd16539d63df2805b5568f1f5688cd2a885d04706f50db9b77ba13c6",
6384                                   "304502210090ed76aeb21b53236a598968abc66e2024691d07b62f53ddbeca8f93144af9c602205f873af5a0c10e62690e9aba09740550f194a9dc455ba4c1c23f6cde7704674c",
6385                                   "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" },
6386                                   { 1,
6387                                   "304402201d0f09d2bf7bc245a4f17980e1e9164290df16c70c6a2ff1592f5030d6108581022061e744a7dc151b36bf0aff7a4f1812ba90b8b03633bb979a270d19858fd960c5",
6388                                   "30450221009aef000d2e843a4202c1b1a2bf554abc9a7902bf49b2cb0759bc507456b7ebad02204e7c3d193ede2fd2b4cd6b39f51a920e581e35575e357e44d7b699c40ce61d39",
6389                                   "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" },
6390                                   { 2,
6391                                   "30440220010bf035d5823596e50dce2076a4d9f942d8d28031c9c428b901a02b6b8140de02203250e8e4a08bc5b4ecdca4d0eedf98223e02e3ac1c0206b3a7ffdb374aa21e5f",
6392                                   "30440220073de0067b88e425b3018b30366bfeda0ccb703118ccd3d02ead08c0f53511d002203fac50ac0e4cf8a3af0b4b1b12e801650591f748f8ddf1e089c160f10b69e511",
6393                                   "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" }
6394                 } );
6395         }
6396
6397         #[test]
6398         fn test_per_commitment_secret_gen() {
6399                 // Test vectors from BOLT 3 Appendix D:
6400
6401                 let mut seed = [0; 32];
6402                 seed[0..32].clone_from_slice(&hex::decode("0000000000000000000000000000000000000000000000000000000000000000").unwrap());
6403                 assert_eq!(chan_utils::build_commitment_secret(&seed, 281474976710655),
6404                            hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap()[..]);
6405
6406                 seed[0..32].clone_from_slice(&hex::decode("FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF").unwrap());
6407                 assert_eq!(chan_utils::build_commitment_secret(&seed, 281474976710655),
6408                            hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap()[..]);
6409
6410                 assert_eq!(chan_utils::build_commitment_secret(&seed, 0xaaaaaaaaaaa),
6411                            hex::decode("56f4008fb007ca9acf0e15b054d5c9fd12ee06cea347914ddbaed70d1c13a528").unwrap()[..]);
6412
6413                 assert_eq!(chan_utils::build_commitment_secret(&seed, 0x555555555555),
6414                            hex::decode("9015daaeb06dba4ccc05b91b2f73bd54405f2be9f217fbacd3c5ac2e62327d31").unwrap()[..]);
6415
6416                 seed[0..32].clone_from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap());
6417                 assert_eq!(chan_utils::build_commitment_secret(&seed, 1),
6418                            hex::decode("915c75942a26bb3a433a8ce2cb0427c29ec6c1775cfc78328b57f6ba7bfeaa9c").unwrap()[..]);
6419         }
6420
6421         #[test]
6422         fn test_key_derivation() {
6423                 // Test vectors from BOLT 3 Appendix E:
6424                 let secp_ctx = Secp256k1::new();
6425
6426                 let base_secret = SecretKey::from_slice(&hex::decode("000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f").unwrap()[..]).unwrap();
6427                 let per_commitment_secret = SecretKey::from_slice(&hex::decode("1f1e1d1c1b1a191817161514131211100f0e0d0c0b0a09080706050403020100").unwrap()[..]).unwrap();
6428
6429                 let base_point = PublicKey::from_secret_key(&secp_ctx, &base_secret);
6430                 assert_eq!(base_point.serialize()[..], hex::decode("036d6caac248af96f6afa7f904f550253a0f3ef3f5aa2fe6838a95b216691468e2").unwrap()[..]);
6431
6432                 let per_commitment_point = PublicKey::from_secret_key(&secp_ctx, &per_commitment_secret);
6433                 assert_eq!(per_commitment_point.serialize()[..], hex::decode("025f7117a78150fe2ef97db7cfc83bd57b2e2c0d0dd25eaf467a4a1c2a45ce1486").unwrap()[..]);
6434
6435                 assert_eq!(chan_utils::derive_public_key(&secp_ctx, &per_commitment_point, &base_point).unwrap().serialize()[..],
6436                                 hex::decode("0235f2dbfaa89b57ec7b055afe29849ef7ddfeb1cefdb9ebdc43f5494984db29e5").unwrap()[..]);
6437
6438                 assert_eq!(chan_utils::derive_private_key(&secp_ctx, &per_commitment_point, &base_secret).unwrap(),
6439                                 SecretKey::from_slice(&hex::decode("cbced912d3b21bf196a766651e436aff192362621ce317704ea2f75d87e7be0f").unwrap()[..]).unwrap());
6440
6441                 assert_eq!(chan_utils::derive_public_revocation_key(&secp_ctx, &per_commitment_point, &base_point).unwrap().serialize()[..],
6442                                 hex::decode("02916e326636d19c33f13e8c0c3a03dd157f332f3e99c317c141dd865eb01f8ff0").unwrap()[..]);
6443
6444                 assert_eq!(chan_utils::derive_private_revocation_key(&secp_ctx, &per_commitment_secret, &base_secret).unwrap(),
6445                                 SecretKey::from_slice(&hex::decode("d09ffff62ddb2297ab000cc85bcb4283fdeb6aa052affbc9dddcf33b61078110").unwrap()[..]).unwrap());
6446         }
6447 }