_ 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::blockdata::opcodes;
  13 use bitcoin::util::bip143;
  14 use bitcoin::consensus::encode;
  15
  16 use bitcoin::hashes::Hash;
  17 use bitcoin::hashes::sha256::Hash as Sha256;
  18 use bitcoin::hash_types::{Txid, BlockHash, WPubkeyHash};
  19
  20 use bitcoin::secp256k1::key::{PublicKey,SecretKey};
  21 use bitcoin::secp256k1::{Secp256k1,Signature};
  22 use bitcoin::secp256k1;
  23
  24 use ln::{PaymentPreimage, PaymentHash};
  25 use ln::features::{ChannelFeatures, InitFeatures};
  26 use ln::msgs;
  27 use ln::msgs::{DecodeError, OptionalField, DataLossProtect};
  28 use ln::channelmanager::{BestBlock, PendingHTLCStatus, HTLCSource, HTLCFailReason, HTLCFailureMsg, PendingHTLCInfo, RAACommitmentOrder, BREAKDOWN_TIMEOUT, MIN_CLTV_EXPIRY_DELTA, MAX_LOCAL_BREAKDOWN_TIMEOUT};
  29 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};
  30 use ln::chan_utils;
  31 use chain::chaininterface::{FeeEstimator,ConfirmationTarget};
  32 use chain::channelmonitor::{ChannelMonitor, ChannelMonitorUpdate, ChannelMonitorUpdateStep, HTLC_FAIL_BACK_BUFFER};
  33 use chain::transaction::{OutPoint, TransactionData};
  34 use chain::keysinterface::{Sign, KeysInterface};
  35 use util::transaction_utils;
  36 use util::ser::{Readable, ReadableArgs, Writeable, Writer, VecWriter};
  37 use util::logger::Logger;
  38 use util::errors::APIError;
  39 use util::config::{UserConfig,ChannelConfig};
  40 use util::scid_utils::scid_from_parts;
  41
  42 use std;
  43 use std::{cmp,mem,fmt};
  44 use std::ops::Deref;
  45 #[cfg(any(test, feature = "fuzztarget"))]
  46 use std::sync::Mutex;
  47 use bitcoin::hashes::hex::ToHex;
  48 use bitcoin::blockdata::opcodes::all::OP_PUSHBYTES_0;
  49
  50 #[cfg(test)]
  51 pub struct ChannelValueStat {
  52         pub value_to_self_msat: u64,
  53         pub channel_value_msat: u64,
  54         pub channel_reserve_msat: u64,
  55         pub pending_outbound_htlcs_amount_msat: u64,
  56         pub pending_inbound_htlcs_amount_msat: u64,
  57         pub holding_cell_outbound_amount_msat: u64,
  58         pub counterparty_max_htlc_value_in_flight_msat: u64, // outgoing
  59         pub counterparty_dust_limit_msat: u64,
  60 }
  61
  62 enum InboundHTLCRemovalReason {
  63         FailRelay(msgs::OnionErrorPacket),
  64         FailMalformed(([u8; 32], u16)),
  65         Fulfill(PaymentPreimage),
  66 }
  67
  68 enum InboundHTLCState {
  69         /// Offered by remote, to be included in next local commitment tx. I.e., the remote sent an
  70         /// update_add_htlc message for this HTLC.
  71         RemoteAnnounced(PendingHTLCStatus),
  72         /// Included in a received commitment_signed message (implying we've
  73         /// revoke_and_ack'd it), but the remote hasn't yet revoked their previous
  74         /// state (see the example below). We have not yet included this HTLC in a
  75         /// commitment_signed message because we are waiting on the remote's
  76         /// aforementioned state revocation. One reason this missing remote RAA
  77         /// (revoke_and_ack) blocks us from constructing a commitment_signed message
  78         /// is because every time we create a new "state", i.e. every time we sign a
  79         /// new commitment tx (see [BOLT #2]), we need a new per_commitment_point,
  80         /// which are provided one-at-a-time in each RAA. E.g., the last RAA they
  81         /// sent provided the per_commitment_point for our current commitment tx.
  82         /// The other reason we should not send a commitment_signed without their RAA
  83         /// is because their RAA serves to ACK our previous commitment_signed.
  84         ///
  85         /// Here's an example of how an HTLC could come to be in this state:
  86         /// remote --> update_add_htlc(prev_htlc)   --> local
  87         /// remote --> commitment_signed(prev_htlc) --> local
  88         /// remote <-- revoke_and_ack               <-- local
  89         /// remote <-- commitment_signed(prev_htlc) <-- local
  90         /// [note that here, the remote does not respond with a RAA]
  91         /// remote --> update_add_htlc(this_htlc)   --> local
  92         /// remote --> commitment_signed(prev_htlc, this_htlc) --> local
  93         /// Now `this_htlc` will be assigned this state. It's unable to be officially
  94         /// accepted, i.e. included in a commitment_signed, because we're missing the
  95         /// RAA that provides our next per_commitment_point. The per_commitment_point
  96         /// is used to derive commitment keys, which are used to construct the
  97         /// signatures in a commitment_signed message.
  98         /// Implies AwaitingRemoteRevoke.
  99         ///
 100         /// [BOLT #2]: https://github.com/lightningnetwork/lightning-rfc/blob/master/02-peer-protocol.md
 101         AwaitingRemoteRevokeToAnnounce(PendingHTLCStatus),
 102         /// Included in a received commitment_signed message (implying we've revoke_and_ack'd it).
 103         /// We have also included this HTLC in our latest commitment_signed and are now just waiting
 104         /// on the remote's revoke_and_ack to make this HTLC an irrevocable part of the state of the
 105         /// channel (before it can then get forwarded and/or removed).
 106         /// Implies AwaitingRemoteRevoke.
 107         AwaitingAnnouncedRemoteRevoke(PendingHTLCStatus),
 108         Committed,
 109         /// Removed by us and a new commitment_signed was sent (if we were AwaitingRemoteRevoke when we
 110         /// created it we would have put it in the holding cell instead). When they next revoke_and_ack
 111         /// we'll drop it.
 112         /// Note that we have to keep an eye on the HTLC until we've received a broadcastable
 113         /// commitment transaction without it as otherwise we'll have to force-close the channel to
 114         /// claim it before the timeout (obviously doesn't apply to revoked HTLCs that we can't claim
 115         /// anyway). That said, ChannelMonitor does this for us (see
 116         /// ChannelMonitor::would_broadcast_at_height) so we actually remove the HTLC from our own
 117         /// local state before then, once we're sure that the next commitment_signed and
 118         /// ChannelMonitor::provide_latest_local_commitment_tx will not include this HTLC.
 119         LocalRemoved(InboundHTLCRemovalReason),
 120 }
 121
 122 struct InboundHTLCOutput {
 123         htlc_id: u64,
 124         amount_msat: u64,
 125         cltv_expiry: u32,
 126         payment_hash: PaymentHash,
 127         state: InboundHTLCState,
 128 }
 129
 130 enum OutboundHTLCState {
 131         /// Added by us and included in a commitment_signed (if we were AwaitingRemoteRevoke when we
 132         /// created it we would have put it in the holding cell instead). When they next revoke_and_ack
 133         /// we will promote to Committed (note that they may not accept it until the next time we
 134         /// revoke, but we don't really care about that:
 135         ///  * they've revoked, so worst case we can announce an old state and get our (option on)
 136         ///    money back (though we won't), and,
 137         ///  * we'll send them a revoke when they send a commitment_signed, and since only they're
 138         ///    allowed to remove it, the "can only be removed once committed on both sides" requirement
 139         ///    doesn't matter to us and it's up to them to enforce it, worst-case they jump ahead but
 140         ///    we'll never get out of sync).
 141         /// Note that we Box the OnionPacket as it's rather large and we don't want to blow up
 142         /// OutboundHTLCOutput's size just for a temporary bit
 143         LocalAnnounced(Box<msgs::OnionPacket>),
 144         Committed,
 145         /// Remote removed this (outbound) HTLC. We're waiting on their commitment_signed to finalize
 146         /// the change (though they'll need to revoke before we fail the payment).
 147         RemoteRemoved(Option<HTLCFailReason>),
 148         /// Remote removed this and sent a commitment_signed (implying we've revoke_and_ack'ed it), but
 149         /// the remote side hasn't yet revoked their previous state, which we need them to do before we
 150         /// can do any backwards failing. Implies AwaitingRemoteRevoke.
 151         /// We also have not yet removed this HTLC in a commitment_signed message, and are waiting on a
 152         /// remote revoke_and_ack on a previous state before we can do so.
 153         AwaitingRemoteRevokeToRemove(Option<HTLCFailReason>),
 154         /// Remote removed this and sent a commitment_signed (implying we've revoke_and_ack'ed it), but
 155         /// the remote side hasn't yet revoked their previous state, which we need them to do before we
 156         /// can do any backwards failing. Implies AwaitingRemoteRevoke.
 157         /// We have removed this HTLC in our latest commitment_signed and are now just waiting on a
 158         /// revoke_and_ack to drop completely.
 159         AwaitingRemovedRemoteRevoke(Option<HTLCFailReason>),
 160 }
 161
 162 struct OutboundHTLCOutput {
 163         htlc_id: u64,
 164         amount_msat: u64,
 165         cltv_expiry: u32,
 166         payment_hash: PaymentHash,
 167         state: OutboundHTLCState,
 168         source: HTLCSource,
 169 }
 170
 171 /// See AwaitingRemoteRevoke ChannelState for more info
 172 enum HTLCUpdateAwaitingACK {
 173         AddHTLC { // TODO: Time out if we're getting close to cltv_expiry
 174                 // always outbound
 175                 amount_msat: u64,
 176                 cltv_expiry: u32,
 177                 payment_hash: PaymentHash,
 178                 source: HTLCSource,
 179                 onion_routing_packet: msgs::OnionPacket,
 180         },
 181         ClaimHTLC {
 182                 payment_preimage: PaymentPreimage,
 183                 htlc_id: u64,
 184         },
 185         FailHTLC {
 186                 htlc_id: u64,
 187                 err_packet: msgs::OnionErrorPacket,
 188         },
 189 }
 190
 191 /// There are a few "states" and then a number of flags which can be applied:
 192 /// We first move through init with OurInitSent -> TheirInitSent -> FundingCreated -> FundingSent.
 193 /// TheirFundingLocked and OurFundingLocked then get set on FundingSent, and when both are set we
 194 /// move on to ChannelFunded.
 195 /// Note that PeerDisconnected can be set on both ChannelFunded and FundingSent.
 196 /// ChannelFunded can then get all remaining flags set on it, until we finish shutdown, then we
 197 /// move on to ShutdownComplete, at which point most calls into this channel are disallowed.
 198 enum ChannelState {
 199         /// Implies we have (or are prepared to) send our open_channel/accept_channel message
 200         OurInitSent = 1 << 0,
 201         /// Implies we have received their open_channel/accept_channel message
 202         TheirInitSent = 1 << 1,
 203         /// We have sent funding_created and are awaiting a funding_signed to advance to FundingSent.
 204         /// Note that this is nonsense for an inbound channel as we immediately generate funding_signed
 205         /// upon receipt of funding_created, so simply skip this state.
 206         FundingCreated = 4,
 207         /// Set when we have received/sent funding_created and funding_signed and are thus now waiting
 208         /// on the funding transaction to confirm. The FundingLocked flags are set to indicate when we
 209         /// and our counterparty consider the funding transaction confirmed.
 210         FundingSent = 8,
 211         /// Flag which can be set on FundingSent to indicate they sent us a funding_locked message.
 212         /// Once both TheirFundingLocked and OurFundingLocked are set, state moves on to ChannelFunded.
 213         TheirFundingLocked = 1 << 4,
 214         /// Flag which can be set on FundingSent to indicate we sent them a funding_locked message.
 215         /// Once both TheirFundingLocked and OurFundingLocked are set, state moves on to ChannelFunded.
 216         OurFundingLocked = 1 << 5,
 217         ChannelFunded = 64,
 218         /// Flag which is set on ChannelFunded and FundingSent indicating remote side is considered
 219         /// "disconnected" and no updates are allowed until after we've done a channel_reestablish
 220         /// dance.
 221         PeerDisconnected = 1 << 7,
 222         /// Flag which is set on ChannelFunded, FundingCreated, and FundingSent indicating the user has
 223         /// told us they failed to update our ChannelMonitor somewhere and we should pause sending any
 224         /// outbound messages until they've managed to do so.
 225         MonitorUpdateFailed = 1 << 8,
 226         /// Flag which implies that we have sent a commitment_signed but are awaiting the responding
 227         /// revoke_and_ack message. During this time period, we can't generate new commitment_signed
 228         /// messages as then we will be unable to determine which HTLCs they included in their
 229         /// revoke_and_ack implicit ACK, so instead we have to hold them away temporarily to be sent
 230         /// later.
 231         /// Flag is set on ChannelFunded.
 232         AwaitingRemoteRevoke = 1 << 9,
 233         /// Flag which is set on ChannelFunded or FundingSent after receiving a shutdown message from
 234         /// the remote end. If set, they may not add any new HTLCs to the channel, and we are expected
 235         /// to respond with our own shutdown message when possible.
 236         RemoteShutdownSent = 1 << 10,
 237         /// Flag which is set on ChannelFunded or FundingSent after sending a shutdown message. At this
 238         /// point, we may not add any new HTLCs to the channel.
 239         /// TODO: Investigate some kind of timeout mechanism by which point the remote end must provide
 240         /// us their shutdown.
 241         LocalShutdownSent = 1 << 11,
 242         /// We've successfully negotiated a closing_signed dance. At this point ChannelManager is about
 243         /// to drop us, but we store this anyway.
 244         ShutdownComplete = 4096,
 245 }
 246 const BOTH_SIDES_SHUTDOWN_MASK: u32 = ChannelState::LocalShutdownSent as u32 | ChannelState::RemoteShutdownSent as u32;
 247 const MULTI_STATE_FLAGS: u32 = BOTH_SIDES_SHUTDOWN_MASK | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32;
 248
 249 pub const INITIAL_COMMITMENT_NUMBER: u64 = (1 << 48) - 1;
 250
 251 /// Liveness is called to fluctuate given peer disconnecton/monitor failures/closing.
 252 /// If channel is public, network should have a liveness view announced by us on a
 253 /// best-effort, which means we may filter out some status transitions to avoid spam.
 254 /// See further timer_tick_occurred.
 255 #[derive(PartialEq)]
 256 enum UpdateStatus {
 257         /// Status has been gossiped.
 258         Fresh,
 259         /// Status has been changed.
 260         DisabledMarked,
 261         /// Status has been marked to be gossiped at next flush
 262         DisabledStaged,
 263 }
 264
 265 /// An enum indicating whether the local or remote side offered a given HTLC.
 266 enum HTLCInitiator {
 267         LocalOffered,
 268         RemoteOffered,
 269 }
 270
 271 /// Used when calculating whether we or the remote can afford an additional HTLC.
 272 struct HTLCCandidate {
 273         amount_msat: u64,
 274         origin: HTLCInitiator,
 275 }
 276
 277 impl HTLCCandidate {
 278         fn new(amount_msat: u64, origin: HTLCInitiator) -> Self {
 279                 Self {
 280                         amount_msat,
 281                         origin,
 282                 }
 283         }
 284 }
 285
 286 /// Information needed for constructing an invoice route hint for this channel.
 287 #[derive(Clone)]
 288 pub struct CounterpartyForwardingInfo {
 289         /// Base routing fee in millisatoshis.
 290         pub fee_base_msat: u32,
 291         /// Amount in millionths of a satoshi the channel will charge per transferred satoshi.
 292         pub fee_proportional_millionths: u32,
 293         /// The minimum difference in cltv_expiry between an ingoing HTLC and its outgoing counterpart,
 294         /// such that the outgoing HTLC is forwardable to this counterparty. See `msgs::ChannelUpdate`'s
 295         /// `cltv_expiry_delta` for more details.
 296         pub cltv_expiry_delta: u16,
 297 }
 298
 299 // TODO: We should refactor this to be an Inbound/OutboundChannel until initial setup handshaking
 300 // has been completed, and then turn into a Channel to get compiler-time enforcement of things like
 301 // calling channel_id() before we're set up or things like get_outbound_funding_signed on an
 302 // inbound channel.
 303 //
 304 // Holder designates channel data owned for the benefice of the user client.
 305 // Counterparty designates channel data owned by the another channel participant entity.
 306 pub(super) struct Channel<Signer: Sign> {
 307         config: ChannelConfig,
 308
 309         user_id: u64,
 310
 311         channel_id: [u8; 32],
 312         channel_state: u32,
 313         secp_ctx: Secp256k1<secp256k1::All>,
 314         channel_value_satoshis: u64,
 315
 316         latest_monitor_update_id: u64,
 317
 318         holder_signer: Signer,
 319         shutdown_pubkey: PublicKey,
 320         destination_script: Script,
 321
 322         // Our commitment numbers start at 2^48-1 and count down, whereas the ones used in transaction
 323         // generation start at 0 and count up...this simplifies some parts of implementation at the
 324         // cost of others, but should really just be changed.
 325
 326         cur_holder_commitment_transaction_number: u64,
 327         cur_counterparty_commitment_transaction_number: u64,
 328         value_to_self_msat: u64, // Excluding all pending_htlcs, excluding fees
 329         pending_inbound_htlcs: Vec<InboundHTLCOutput>,
 330         pending_outbound_htlcs: Vec<OutboundHTLCOutput>,
 331         holding_cell_htlc_updates: Vec<HTLCUpdateAwaitingACK>,
 332
 333         /// When resending CS/RAA messages on channel monitor restoration or on reconnect, we always
 334         /// need to ensure we resend them in the order we originally generated them. Note that because
 335         /// there can only ever be one in-flight CS and/or one in-flight RAA at any time, it is
 336         /// sufficient to simply set this to the opposite of any message we are generating as we
 337         /// generate it. ie when we generate a CS, we set this to RAAFirst as, if there is a pending
 338         /// in-flight RAA to resend, it will have been the first thing we generated, and thus we should
 339         /// send it first.
 340         resend_order: RAACommitmentOrder,
 341
 342         monitor_pending_funding_locked: bool,
 343         monitor_pending_revoke_and_ack: bool,
 344         monitor_pending_commitment_signed: bool,
 345         monitor_pending_forwards: Vec<(PendingHTLCInfo, u64)>,
 346         monitor_pending_failures: Vec<(HTLCSource, PaymentHash, HTLCFailReason)>,
 347
 348         // pending_update_fee is filled when sending and receiving update_fee
 349         // For outbound channel, feerate_per_kw is updated with the value from
 350         // pending_update_fee when revoke_and_ack is received
 351         //
 352         // For inbound channel, feerate_per_kw is updated when it receives
 353         // commitment_signed and revoke_and_ack is generated
 354         // The pending value is kept when another pair of update_fee and commitment_signed
 355         // is received during AwaitingRemoteRevoke and relieved when the expected
 356         // revoke_and_ack is received and new commitment_signed is generated to be
 357         // sent to the funder. Otherwise, the pending value is removed when receiving
 358         // commitment_signed.
 359         pending_update_fee: Option<u32>,
 360         // update_fee() during ChannelState::AwaitingRemoteRevoke is hold in
 361         // holdina_cell_update_fee then moved to pending_udpate_fee when revoke_and_ack
 362         // is received. holding_cell_update_fee is updated when there are additional
 363         // update_fee() during ChannelState::AwaitingRemoteRevoke.
 364         holding_cell_update_fee: Option<u32>,
 365         next_holder_htlc_id: u64,
 366         next_counterparty_htlc_id: u64,
 367         update_time_counter: u32,
 368         feerate_per_kw: u32,
 369
 370         #[cfg(debug_assertions)]
 371         /// Max to_local and to_remote outputs in a locally-generated commitment transaction
 372         holder_max_commitment_tx_output: ::std::sync::Mutex<(u64, u64)>,
 373         #[cfg(debug_assertions)]
 374         /// Max to_local and to_remote outputs in a remote-generated commitment transaction
 375         counterparty_max_commitment_tx_output: ::std::sync::Mutex<(u64, u64)>,
 376
 377         last_sent_closing_fee: Option<(u32, u64, Signature)>, // (feerate, fee, holder_sig)
 378
 379         /// The hash of the block in which the funding transaction was included.
 380         funding_tx_confirmed_in: Option<BlockHash>,
 381         funding_tx_confirmation_height: u32,
 382         short_channel_id: Option<u64>,
 383
 384         counterparty_dust_limit_satoshis: u64,
 385         #[cfg(test)]
 386         pub(super) holder_dust_limit_satoshis: u64,
 387         #[cfg(not(test))]
 388         holder_dust_limit_satoshis: u64,
 389         #[cfg(test)]
 390         pub(super) counterparty_max_htlc_value_in_flight_msat: u64,
 391         #[cfg(not(test))]
 392         counterparty_max_htlc_value_in_flight_msat: u64,
 393         //get_holder_max_htlc_value_in_flight_msat(): u64,
 394         /// minimum channel reserve for self to maintain - set by them.
 395         counterparty_selected_channel_reserve_satoshis: u64,
 396         // get_holder_selected_channel_reserve_satoshis(channel_value_sats: u64): u64
 397         counterparty_htlc_minimum_msat: u64,
 398         holder_htlc_minimum_msat: u64,
 399         #[cfg(test)]
 400         pub counterparty_max_accepted_htlcs: u16,
 401         #[cfg(not(test))]
 402         counterparty_max_accepted_htlcs: u16,
 403         //implied by OUR_MAX_HTLCS: max_accepted_htlcs: u16,
 404         minimum_depth: u32,
 405
 406         counterparty_forwarding_info: Option<CounterpartyForwardingInfo>,
 407
 408         pub(crate) channel_transaction_parameters: ChannelTransactionParameters,
 409         funding_transaction: Option<Transaction>,
 410
 411         counterparty_cur_commitment_point: Option<PublicKey>,
 412         counterparty_prev_commitment_point: Option<PublicKey>,
 413         counterparty_node_id: PublicKey,
 414
 415         counterparty_shutdown_scriptpubkey: Option<Script>,
 416
 417         commitment_secrets: CounterpartyCommitmentSecrets,
 418
 419         network_sync: UpdateStatus,
 420
 421         // We save these values so we can make sure `next_local_commit_tx_fee_msat` and
 422         // `next_remote_commit_tx_fee_msat` properly predict what the next commitment transaction fee will
 423         // be, by comparing the cached values to the fee of the tranaction generated by
 424         // `build_commitment_transaction`.
 425         #[cfg(any(test, feature = "fuzztarget"))]
 426         next_local_commitment_tx_fee_info_cached: Mutex<Option<CommitmentTxInfoCached>>,
 427         #[cfg(any(test, feature = "fuzztarget"))]
 428         next_remote_commitment_tx_fee_info_cached: Mutex<Option<CommitmentTxInfoCached>>,
 429 }
 430
 431 #[cfg(any(test, feature = "fuzztarget"))]
 432 struct CommitmentTxInfoCached {
 433         fee: u64,
 434         total_pending_htlcs: usize,
 435         next_holder_htlc_id: u64,
 436         next_counterparty_htlc_id: u64,
 437         feerate: u32,
 438 }
 439
 440 pub const OUR_MAX_HTLCS: u16 = 50; //TODO
 441 const SPENDING_INPUT_FOR_A_OUTPUT_WEIGHT: u64 = 79; // prevout: 36, nSequence: 4, script len: 1, witness lengths: (3+1)/4, sig: 73/4, if-selector: 1, redeemScript: (6 ops + 2*33 pubkeys + 1*2 delay)/4
 442 const B_OUTPUT_PLUS_SPENDING_INPUT_WEIGHT: u64 = 104; // prevout: 40, nSequence: 4, script len: 1, witness lengths: 3/4, sig: 73/4, pubkey: 33/4, output: 31 (TODO: Wrong? Useless?)
 443
 444 #[cfg(not(test))]
 445 const COMMITMENT_TX_BASE_WEIGHT: u64 = 724;
 446 #[cfg(test)]
 447 pub const COMMITMENT_TX_BASE_WEIGHT: u64 = 724;
 448 #[cfg(not(test))]
 449 const COMMITMENT_TX_WEIGHT_PER_HTLC: u64 = 172;
 450 #[cfg(test)]
 451 pub const COMMITMENT_TX_WEIGHT_PER_HTLC: u64 = 172;
 452
 453 /// Maximmum `funding_satoshis` value, according to the BOLT #2 specification
 454 /// it's 2^24.
 455 pub const MAX_FUNDING_SATOSHIS: u64 = 1 << 24;
 456
 457 /// Used to return a simple Error back to ChannelManager. Will get converted to a
 458 /// msgs::ErrorAction::SendErrorMessage or msgs::ErrorAction::IgnoreError as appropriate with our
 459 /// channel_id in ChannelManager.
 460 pub(super) enum ChannelError {
 461         Ignore(String),
 462         Close(String),
 463         CloseDelayBroadcast(String),
 464 }
 465
 466 impl fmt::Debug for ChannelError {
 467         fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
 468                 match self {
 469                         &ChannelError::Ignore(ref e) => write!(f, "Ignore : {}", e),
 470                         &ChannelError::Close(ref e) => write!(f, "Close : {}", e),
 471                         &ChannelError::CloseDelayBroadcast(ref e) => write!(f, "CloseDelayBroadcast : {}", e)
 472                 }
 473         }
 474 }
 475
 476 macro_rules! secp_check {
 477         ($res: expr, $err: expr) => {
 478                 match $res {
 479                         Ok(thing) => thing,
 480                         Err(_) => return Err(ChannelError::Close($err)),
 481                 }
 482         };
 483 }
 484
 485 impl<Signer: Sign> Channel<Signer> {
 486         // Convert constants + channel value to limits:
 487         fn get_holder_max_htlc_value_in_flight_msat(channel_value_satoshis: u64) -> u64 {
 488                 channel_value_satoshis * 1000 / 10 //TODO
 489         }
 490
 491         /// Returns a minimum channel reserve value the remote needs to maintain,
 492         /// required by us.
 493         ///
 494         /// Guaranteed to return a value no larger than channel_value_satoshis
 495         pub(crate) fn get_holder_selected_channel_reserve_satoshis(channel_value_satoshis: u64) -> u64 {
 496                 let (q, _) = channel_value_satoshis.overflowing_div(100);
 497                 cmp::min(channel_value_satoshis, cmp::max(q, 1000)) //TODO
 498         }
 499
 500         fn derive_holder_dust_limit_satoshis(at_open_background_feerate: u32) -> u64 {
 501                 cmp::max(at_open_background_feerate as u64 * B_OUTPUT_PLUS_SPENDING_INPUT_WEIGHT / 1000, 546) //TODO
 502         }
 503
 504         // Constructors:
 505         pub fn new_outbound<K: Deref, F: Deref>(fee_estimator: &F, keys_provider: &K, counterparty_node_id: PublicKey, channel_value_satoshis: u64, push_msat: u64, user_id: u64, config: &UserConfig) -> Result<Channel<Signer>, APIError>
 506         where K::Target: KeysInterface<Signer = Signer>,
 507               F::Target: FeeEstimator,
 508         {
 509                 let holder_selected_contest_delay = config.own_channel_config.our_to_self_delay;
 510                 let holder_signer = keys_provider.get_channel_signer(false, channel_value_satoshis);
 511                 let pubkeys = holder_signer.pubkeys().clone();
 512
 513                 if channel_value_satoshis >= MAX_FUNDING_SATOSHIS {
 514                         return Err(APIError::APIMisuseError{err: format!("funding_value must be smaller than {}, it was {}", MAX_FUNDING_SATOSHIS, channel_value_satoshis)});
 515                 }
 516                 let channel_value_msat = channel_value_satoshis * 1000;
 517                 if push_msat > channel_value_msat {
 518                         return Err(APIError::APIMisuseError { err: format!("Push value ({}) was larger than channel_value ({})", push_msat, channel_value_msat) });
 519                 }
 520                 if holder_selected_contest_delay < BREAKDOWN_TIMEOUT {
 521                         return Err(APIError::APIMisuseError {err: format!("Configured with an unreasonable our_to_self_delay ({}) putting user funds at risks", holder_selected_contest_delay)});
 522                 }
 523                 let background_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background);
 524                 if Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(channel_value_satoshis) < Channel::<Signer>::derive_holder_dust_limit_satoshis(background_feerate) {
 525                         return Err(APIError::FeeRateTooHigh{err: format!("Not enough reserve above dust limit can be found at current fee rate({})", background_feerate), feerate: background_feerate});
 526                 }
 527
 528                 let feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Normal);
 529
 530                 let mut secp_ctx = Secp256k1::new();
 531                 secp_ctx.seeded_randomize(&keys_provider.get_secure_random_bytes());
 532
 533                 Ok(Channel {
 534                         user_id,
 535                         config: config.channel_options.clone(),
 536
 537                         channel_id: keys_provider.get_secure_random_bytes(),
 538                         channel_state: ChannelState::OurInitSent as u32,
 539                         secp_ctx,
 540                         channel_value_satoshis,
 541
 542                         latest_monitor_update_id: 0,
 543
 544                         holder_signer,
 545                         shutdown_pubkey: keys_provider.get_shutdown_pubkey(),
 546                         destination_script: keys_provider.get_destination_script(),
 547
 548                         cur_holder_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
 549                         cur_counterparty_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
 550                         value_to_self_msat: channel_value_satoshis * 1000 - push_msat,
 551
 552                         pending_inbound_htlcs: Vec::new(),
 553                         pending_outbound_htlcs: Vec::new(),
 554                         holding_cell_htlc_updates: Vec::new(),
 555                         pending_update_fee: None,
 556                         holding_cell_update_fee: None,
 557                         next_holder_htlc_id: 0,
 558                         next_counterparty_htlc_id: 0,
 559                         update_time_counter: 1,
 560
 561                         resend_order: RAACommitmentOrder::CommitmentFirst,
 562
 563                         monitor_pending_funding_locked: false,
 564                         monitor_pending_revoke_and_ack: false,
 565                         monitor_pending_commitment_signed: false,
 566                         monitor_pending_forwards: Vec::new(),
 567                         monitor_pending_failures: Vec::new(),
 568
 569                         #[cfg(debug_assertions)]
 570                         holder_max_commitment_tx_output: ::std::sync::Mutex::new((channel_value_satoshis * 1000 - push_msat, push_msat)),
 571                         #[cfg(debug_assertions)]
 572                         counterparty_max_commitment_tx_output: ::std::sync::Mutex::new((channel_value_satoshis * 1000 - push_msat, push_msat)),
 573
 574                         last_sent_closing_fee: None,
 575
 576                         funding_tx_confirmed_in: None,
 577                         funding_tx_confirmation_height: 0,
 578                         short_channel_id: None,
 579
 580                         feerate_per_kw: feerate,
 581                         counterparty_dust_limit_satoshis: 0,
 582                         holder_dust_limit_satoshis: Channel::<Signer>::derive_holder_dust_limit_satoshis(background_feerate),
 583                         counterparty_max_htlc_value_in_flight_msat: 0,
 584                         counterparty_selected_channel_reserve_satoshis: 0,
 585                         counterparty_htlc_minimum_msat: 0,
 586                         holder_htlc_minimum_msat: if config.own_channel_config.our_htlc_minimum_msat == 0 { 1 } else { config.own_channel_config.our_htlc_minimum_msat },
 587                         counterparty_max_accepted_htlcs: 0,
 588                         minimum_depth: 0, // Filled in in accept_channel
 589
 590                         counterparty_forwarding_info: None,
 591
 592                         channel_transaction_parameters: ChannelTransactionParameters {
 593                                 holder_pubkeys: pubkeys,
 594                                 holder_selected_contest_delay: config.own_channel_config.our_to_self_delay,
 595                                 is_outbound_from_holder: true,
 596                                 counterparty_parameters: None,
 597                                 funding_outpoint: None
 598                         },
 599                         funding_transaction: None,
 600
 601                         counterparty_cur_commitment_point: None,
 602                         counterparty_prev_commitment_point: None,
 603                         counterparty_node_id,
 604
 605                         counterparty_shutdown_scriptpubkey: None,
 606
 607                         commitment_secrets: CounterpartyCommitmentSecrets::new(),
 608
 609                         network_sync: UpdateStatus::Fresh,
 610
 611                         #[cfg(any(test, feature = "fuzztarget"))]
 612                         next_local_commitment_tx_fee_info_cached: Mutex::new(None),
 613                         #[cfg(any(test, feature = "fuzztarget"))]
 614                         next_remote_commitment_tx_fee_info_cached: Mutex::new(None),
 615                 })
 616         }
 617
 618         fn check_remote_fee<F: Deref>(fee_estimator: &F, feerate_per_kw: u32) -> Result<(), ChannelError>
 619                 where F::Target: FeeEstimator
 620         {
 621                 let lower_limit = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background);
 622                 if feerate_per_kw < lower_limit {
 623                         return Err(ChannelError::Close(format!("Peer's feerate much too low. Actual: {}. Our expected lower limit: {}", feerate_per_kw, lower_limit)));
 624                 }
 625                 let upper_limit = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::HighPriority) as u64  * 2;
 626                 if feerate_per_kw as u64 > upper_limit {
 627                         return Err(ChannelError::Close(format!("Peer's feerate much too high. Actual: {}. Our expected upper limit: {}", feerate_per_kw, upper_limit)));
 628                 }
 629                 Ok(())
 630         }
 631
 632         /// Creates a new channel from a remote sides' request for one.
 633         /// Assumes chain_hash has already been checked and corresponds with what we expect!
 634         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>
 635                 where K::Target: KeysInterface<Signer = Signer>,
 636           F::Target: FeeEstimator
 637         {
 638                 let holder_signer = keys_provider.get_channel_signer(true, msg.funding_satoshis);
 639                 let pubkeys = holder_signer.pubkeys().clone();
 640                 let counterparty_pubkeys = ChannelPublicKeys {
 641                         funding_pubkey: msg.funding_pubkey,
 642                         revocation_basepoint: msg.revocation_basepoint,
 643                         payment_point: msg.payment_point,
 644                         delayed_payment_basepoint: msg.delayed_payment_basepoint,
 645                         htlc_basepoint: msg.htlc_basepoint
 646                 };
 647                 let mut local_config = (*config).channel_options.clone();
 648
 649                 if config.own_channel_config.our_to_self_delay < BREAKDOWN_TIMEOUT {
 650                         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)));
 651                 }
 652
 653                 // Check sanity of message fields:
 654                 if msg.funding_satoshis >= MAX_FUNDING_SATOSHIS {
 655                         return Err(ChannelError::Close(format!("Funding must be smaller than {}. It was {}", MAX_FUNDING_SATOSHIS, msg.funding_satoshis)));
 656                 }
 657                 if msg.channel_reserve_satoshis > msg.funding_satoshis {
 658                         return Err(ChannelError::Close(format!("Bogus channel_reserve_satoshis ({}). Must be not greater than funding_satoshis: {}", msg.channel_reserve_satoshis, msg.funding_satoshis)));
 659                 }
 660                 let funding_value = (msg.funding_satoshis - msg.channel_reserve_satoshis) * 1000;
 661                 if msg.push_msat > funding_value {
 662                         return Err(ChannelError::Close(format!("push_msat {} was larger than funding value {}", msg.push_msat, funding_value)));
 663                 }
 664                 if msg.dust_limit_satoshis > msg.funding_satoshis {
 665                         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)));
 666                 }
 667                 if msg.dust_limit_satoshis > msg.channel_reserve_satoshis {
 668                         return Err(ChannelError::Close(format!("Bogus; channel reserve ({}) is less than dust limit ({})", msg.channel_reserve_satoshis, msg.dust_limit_satoshis)));
 669                 }
 670                 let full_channel_value_msat = (msg.funding_satoshis - msg.channel_reserve_satoshis) * 1000;
 671                 if msg.htlc_minimum_msat >= full_channel_value_msat {
 672                         return Err(ChannelError::Close(format!("Minimum htlc value ({}) was larger than full channel value ({})", msg.htlc_minimum_msat, full_channel_value_msat)));
 673                 }
 674                 Channel::<Signer>::check_remote_fee(fee_estimator, msg.feerate_per_kw)?;
 675
 676                 let max_counterparty_selected_contest_delay = u16::min(config.peer_channel_config_limits.their_to_self_delay, MAX_LOCAL_BREAKDOWN_TIMEOUT);
 677                 if msg.to_self_delay > max_counterparty_selected_contest_delay {
 678                         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)));
 679                 }
 680                 if msg.max_accepted_htlcs < 1 {
 681                         return Err(ChannelError::Close("0 max_accepted_htlcs makes for a useless channel".to_owned()));
 682                 }
 683                 if msg.max_accepted_htlcs > MAX_HTLCS {
 684                         return Err(ChannelError::Close(format!("max_accepted_htlcs was {}. It must not be larger than {}", msg.max_accepted_htlcs, MAX_HTLCS)));
 685                 }
 686
 687                 // Now check against optional parameters as set by config...
 688                 if msg.funding_satoshis < config.peer_channel_config_limits.min_funding_satoshis {
 689                         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)));
 690                 }
 691                 if msg.htlc_minimum_msat > config.peer_channel_config_limits.max_htlc_minimum_msat {
 692                         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)));
 693                 }
 694                 if msg.max_htlc_value_in_flight_msat < config.peer_channel_config_limits.min_max_htlc_value_in_flight_msat {
 695                         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)));
 696                 }
 697                 if msg.channel_reserve_satoshis > config.peer_channel_config_limits.max_channel_reserve_satoshis {
 698                         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)));
 699                 }
 700                 if msg.max_accepted_htlcs < config.peer_channel_config_limits.min_max_accepted_htlcs {
 701                         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)));
 702                 }
 703                 if msg.dust_limit_satoshis < config.peer_channel_config_limits.min_dust_limit_satoshis {
 704                         return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is less than the user specified limit ({})", msg.dust_limit_satoshis, config.peer_channel_config_limits.min_dust_limit_satoshis)));
 705                 }
 706                 if msg.dust_limit_satoshis > config.peer_channel_config_limits.max_dust_limit_satoshis {
 707                         return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is greater than the user specified limit ({})", msg.dust_limit_satoshis, config.peer_channel_config_limits.max_dust_limit_satoshis)));
 708                 }
 709
 710                 // Convert things into internal flags and prep our state:
 711
 712                 let announce = if (msg.channel_flags & 1) == 1 { true } else { false };
 713                 if config.peer_channel_config_limits.force_announced_channel_preference {
 714                         if local_config.announced_channel != announce {
 715                                 return Err(ChannelError::Close("Peer tried to open channel but their announcement preference is different from ours".to_owned()));
 716                         }
 717                 }
 718                 // we either accept their preference or the preferences match
 719                 local_config.announced_channel = announce;
 720
 721                 let background_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background);
 722
 723                 let holder_dust_limit_satoshis = Channel::<Signer>::derive_holder_dust_limit_satoshis(background_feerate);
 724                 let holder_selected_channel_reserve_satoshis = Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(msg.funding_satoshis);
 725                 if holder_selected_channel_reserve_satoshis < holder_dust_limit_satoshis {
 726                         return Err(ChannelError::Close(format!("Suitable channel reserve not found. remote_channel_reserve was ({}). dust_limit_satoshis is ({}).", holder_selected_channel_reserve_satoshis, holder_dust_limit_satoshis)));
 727                 }
 728                 if msg.channel_reserve_satoshis < holder_dust_limit_satoshis {
 729                         return Err(ChannelError::Close(format!("channel_reserve_satoshis ({}) is smaller than our dust limit ({})", msg.channel_reserve_satoshis, holder_dust_limit_satoshis)));
 730                 }
 731                 if holder_selected_channel_reserve_satoshis < msg.dust_limit_satoshis {
 732                         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)));
 733                 }
 734
 735                 // check if the funder's amount for the initial commitment tx is sufficient
 736                 // for full fee payment
 737                 let funders_amount_msat = msg.funding_satoshis * 1000 - msg.push_msat;
 738                 let lower_limit = background_feerate as u64 * COMMITMENT_TX_BASE_WEIGHT;
 739                 if funders_amount_msat < lower_limit {
 740                         return Err(ChannelError::Close(format!("Insufficient funding amount ({}) for initial commitment. Must be at least {}", funders_amount_msat, lower_limit)));
 741                 }
 742
 743                 let to_local_msat = msg.push_msat;
 744                 let to_remote_msat = funders_amount_msat - background_feerate as u64 * COMMITMENT_TX_BASE_WEIGHT;
 745                 if to_local_msat <= msg.channel_reserve_satoshis * 1000 && to_remote_msat <= holder_selected_channel_reserve_satoshis * 1000 {
 746                         return Err(ChannelError::Close("Insufficient funding amount for initial commitment".to_owned()));
 747                 }
 748
 749                 let counterparty_shutdown_scriptpubkey = if their_features.supports_upfront_shutdown_script() {
 750                         match &msg.shutdown_scriptpubkey {
 751                                 &OptionalField::Present(ref script) => {
 752                                         // Peer is signaling upfront_shutdown and has opt-out with a 0-length script. We don't enforce anything
 753                                         if script.len() == 0 {
 754                                                 None
 755                                         // Peer is signaling upfront_shutdown and has provided a non-accepted scriptpubkey format. Fail the channel
 756                                         } else if is_unsupported_shutdown_script(&their_features, script) {
 757                                                 return Err(ChannelError::Close(format!("Peer is signaling upfront_shutdown but has provided a non-accepted scriptpubkey format. script: ({})", script.to_bytes().to_hex())));
 758                                         } else {
 759                                                 Some(script.clone())
 760                                         }
 761                                 },
 762                                 // 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
 763                                 &OptionalField::Absent => {
 764                                         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()));
 765                                 }
 766                         }
 767                 } else { None };
 768
 769                 let mut secp_ctx = Secp256k1::new();
 770                 secp_ctx.seeded_randomize(&keys_provider.get_secure_random_bytes());
 771
 772                 let chan = Channel {
 773                         user_id,
 774                         config: local_config,
 775
 776                         channel_id: msg.temporary_channel_id,
 777                         channel_state: (ChannelState::OurInitSent as u32) | (ChannelState::TheirInitSent as u32),
 778                         secp_ctx,
 779
 780                         latest_monitor_update_id: 0,
 781
 782                         holder_signer,
 783                         shutdown_pubkey: keys_provider.get_shutdown_pubkey(),
 784                         destination_script: keys_provider.get_destination_script(),
 785
 786                         cur_holder_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
 787                         cur_counterparty_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
 788                         value_to_self_msat: msg.push_msat,
 789
 790                         pending_inbound_htlcs: Vec::new(),
 791                         pending_outbound_htlcs: Vec::new(),
 792                         holding_cell_htlc_updates: Vec::new(),
 793                         pending_update_fee: None,
 794                         holding_cell_update_fee: None,
 795                         next_holder_htlc_id: 0,
 796                         next_counterparty_htlc_id: 0,
 797                         update_time_counter: 1,
 798
 799                         resend_order: RAACommitmentOrder::CommitmentFirst,
 800
 801                         monitor_pending_funding_locked: false,
 802                         monitor_pending_revoke_and_ack: false,
 803                         monitor_pending_commitment_signed: false,
 804                         monitor_pending_forwards: Vec::new(),
 805                         monitor_pending_failures: Vec::new(),
 806
 807                         #[cfg(debug_assertions)]
 808                         holder_max_commitment_tx_output: ::std::sync::Mutex::new((msg.push_msat, msg.funding_satoshis * 1000 - msg.push_msat)),
 809                         #[cfg(debug_assertions)]
 810                         counterparty_max_commitment_tx_output: ::std::sync::Mutex::new((msg.push_msat, msg.funding_satoshis * 1000 - msg.push_msat)),
 811
 812                         last_sent_closing_fee: None,
 813
 814                         funding_tx_confirmed_in: None,
 815                         funding_tx_confirmation_height: 0,
 816                         short_channel_id: None,
 817
 818                         feerate_per_kw: msg.feerate_per_kw,
 819                         channel_value_satoshis: msg.funding_satoshis,
 820                         counterparty_dust_limit_satoshis: msg.dust_limit_satoshis,
 821                         holder_dust_limit_satoshis,
 822                         counterparty_max_htlc_value_in_flight_msat: cmp::min(msg.max_htlc_value_in_flight_msat, msg.funding_satoshis * 1000),
 823                         counterparty_selected_channel_reserve_satoshis: msg.channel_reserve_satoshis,
 824                         counterparty_htlc_minimum_msat: msg.htlc_minimum_msat,
 825                         holder_htlc_minimum_msat: if config.own_channel_config.our_htlc_minimum_msat == 0 { 1 } else { config.own_channel_config.our_htlc_minimum_msat },
 826                         counterparty_max_accepted_htlcs: msg.max_accepted_htlcs,
 827                         minimum_depth: config.own_channel_config.minimum_depth,
 828
 829                         counterparty_forwarding_info: None,
 830
 831                         channel_transaction_parameters: ChannelTransactionParameters {
 832                                 holder_pubkeys: pubkeys,
 833                                 holder_selected_contest_delay: config.own_channel_config.our_to_self_delay,
 834                                 is_outbound_from_holder: false,
 835                                 counterparty_parameters: Some(CounterpartyChannelTransactionParameters {
 836                                         selected_contest_delay: msg.to_self_delay,
 837                                         pubkeys: counterparty_pubkeys,
 838                                 }),
 839                                 funding_outpoint: None
 840                         },
 841                         funding_transaction: None,
 842
 843                         counterparty_cur_commitment_point: Some(msg.first_per_commitment_point),
 844                         counterparty_prev_commitment_point: None,
 845                         counterparty_node_id,
 846
 847                         counterparty_shutdown_scriptpubkey,
 848
 849                         commitment_secrets: CounterpartyCommitmentSecrets::new(),
 850
 851                         network_sync: UpdateStatus::Fresh,
 852
 853                         #[cfg(any(test, feature = "fuzztarget"))]
 854                         next_local_commitment_tx_fee_info_cached: Mutex::new(None),
 855                         #[cfg(any(test, feature = "fuzztarget"))]
 856                         next_remote_commitment_tx_fee_info_cached: Mutex::new(None),
 857                 };
 858
 859                 Ok(chan)
 860         }
 861
 862         /// Transaction nomenclature is somewhat confusing here as there are many different cases - a
 863         /// transaction is referred to as "a's transaction" implying that a will be able to broadcast
 864         /// the transaction. Thus, b will generally be sending a signature over such a transaction to
 865         /// a, and a can revoke the transaction by providing b the relevant per_commitment_secret. As
 866         /// such, a transaction is generally the result of b increasing the amount paid to a (or adding
 867         /// an HTLC to a).
 868         /// @local is used only to convert relevant internal structures which refer to remote vs local
 869         /// to decide value of outputs and direction of HTLCs.
 870         /// @generated_by_local is used to determine *which* HTLCs to include - noting that the HTLC
 871         /// state may indicate that one peer has informed the other that they'd like to add an HTLC but
 872         /// have not yet committed it. Such HTLCs will only be included in transactions which are being
 873         /// generated by the peer which proposed adding the HTLCs, and thus we need to understand both
 874         /// which peer generated this transaction and "to whom" this transaction flows.
 875         /// Returns (the transaction info, the number of HTLC outputs which were present in the
 876         /// transaction, the list of HTLCs which were not ignored when building the transaction).
 877         /// Note that below-dust HTLCs are included in the third return value, but not the second, and
 878         /// sources are provided only for outbound HTLCs in the third return value.
 879         #[inline]
 880         fn build_commitment_transaction<L: Deref>(&self, commitment_number: u64, keys: &TxCreationKeys, local: bool, generated_by_local: bool, feerate_per_kw: u32, logger: &L) -> (CommitmentTransaction, usize, Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)>) where L::Target: Logger {
 881                 let mut included_dust_htlcs: Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)> = Vec::new();
 882                 let num_htlcs = self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len();
 883                 let mut included_non_dust_htlcs: Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)> = Vec::with_capacity(num_htlcs);
 884
 885                 let broadcaster_dust_limit_satoshis = if local { self.holder_dust_limit_satoshis } else { self.counterparty_dust_limit_satoshis };
 886                 let mut remote_htlc_total_msat = 0;
 887                 let mut local_htlc_total_msat = 0;
 888                 let mut value_to_self_msat_offset = 0;
 889
 890                 log_trace!(logger, "Building commitment transaction number {} (really {} xor {}) for {}, generated by {} with fee {}...", commitment_number, (INITIAL_COMMITMENT_NUMBER - commitment_number), get_commitment_transaction_number_obscure_factor(&self.get_holder_pubkeys().payment_point, &self.get_counterparty_pubkeys().payment_point, self.is_outbound()), if local { "us" } else { "remote" }, if generated_by_local { "us" } else { "remote" }, feerate_per_kw);
 891
 892                 macro_rules! get_htlc_in_commitment {
 893                         ($htlc: expr, $offered: expr) => {
 894                                 HTLCOutputInCommitment {
 895                                         offered: $offered,
 896                                         amount_msat: $htlc.amount_msat,
 897                                         cltv_expiry: $htlc.cltv_expiry,
 898                                         payment_hash: $htlc.payment_hash,
 899                                         transaction_output_index: None
 900                                 }
 901                         }
 902                 }
 903
 904                 macro_rules! add_htlc_output {
 905                         ($htlc: expr, $outbound: expr, $source: expr, $state_name: expr) => {
 906                                 if $outbound == local { // "offered HTLC output"
 907                                         let htlc_in_tx = get_htlc_in_commitment!($htlc, true);
 908                                         if $htlc.amount_msat / 1000 >= broadcaster_dust_limit_satoshis + (feerate_per_kw as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000) {
 909                                                 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);
 910                                                 included_non_dust_htlcs.push((htlc_in_tx, $source));
 911                                         } else {
 912                                                 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);
 913                                                 included_dust_htlcs.push((htlc_in_tx, $source));
 914                                         }
 915                                 } else {
 916                                         let htlc_in_tx = get_htlc_in_commitment!($htlc, false);
 917                                         if $htlc.amount_msat / 1000 >= broadcaster_dust_limit_satoshis + (feerate_per_kw as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) {
 918                                                 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);
 919                                                 included_non_dust_htlcs.push((htlc_in_tx, $source));
 920                                         } else {
 921                                                 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);
 922                                                 included_dust_htlcs.push((htlc_in_tx, $source));
 923                                         }
 924                                 }
 925                         }
 926                 }
 927
 928                 for ref htlc in self.pending_inbound_htlcs.iter() {
 929                         let (include, state_name) = match htlc.state {
 930                                 InboundHTLCState::RemoteAnnounced(_) => (!generated_by_local, "RemoteAnnounced"),
 931                                 InboundHTLCState::AwaitingRemoteRevokeToAnnounce(_) => (!generated_by_local, "AwaitingRemoteRevokeToAnnounce"),
 932                                 InboundHTLCState::AwaitingAnnouncedRemoteRevoke(_) => (true, "AwaitingAnnouncedRemoteRevoke"),
 933                                 InboundHTLCState::Committed => (true, "Committed"),
 934                                 InboundHTLCState::LocalRemoved(_) => (!generated_by_local, "LocalRemoved"),
 935                         };
 936
 937                         if include {
 938                                 add_htlc_output!(htlc, false, None, state_name);
 939                                 remote_htlc_total_msat += htlc.amount_msat;
 940                         } else {
 941                                 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);
 942                                 match &htlc.state {
 943                                         &InboundHTLCState::LocalRemoved(ref reason) => {
 944                                                 if generated_by_local {
 945                                                         if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
 946                                                                 value_to_self_msat_offset += htlc.amount_msat as i64;
 947                                                         }
 948                                                 }
 949                                         },
 950                                         _ => {},
 951                                 }
 952                         }
 953                 }
 954
 955                 for ref htlc in self.pending_outbound_htlcs.iter() {
 956                         let (include, state_name) = match htlc.state {
 957                                 OutboundHTLCState::LocalAnnounced(_) => (generated_by_local, "LocalAnnounced"),
 958                                 OutboundHTLCState::Committed => (true, "Committed"),
 959                                 OutboundHTLCState::RemoteRemoved(_) => (generated_by_local, "RemoteRemoved"),
 960                                 OutboundHTLCState::AwaitingRemoteRevokeToRemove(_) => (generated_by_local, "AwaitingRemoteRevokeToRemove"),
 961                                 OutboundHTLCState::AwaitingRemovedRemoteRevoke(_) => (false, "AwaitingRemovedRemoteRevoke"),
 962                         };
 963
 964                         if include {
 965                                 add_htlc_output!(htlc, true, Some(&htlc.source), state_name);
 966                                 local_htlc_total_msat += htlc.amount_msat;
 967                         } else {
 968                                 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);
 969                                 match htlc.state {
 970                                         OutboundHTLCState::AwaitingRemoteRevokeToRemove(None)|OutboundHTLCState::AwaitingRemovedRemoteRevoke(None) => {
 971                                                 value_to_self_msat_offset -= htlc.amount_msat as i64;
 972                                         },
 973                                         OutboundHTLCState::RemoteRemoved(None) => {
 974                                                 if !generated_by_local {
 975                                                         value_to_self_msat_offset -= htlc.amount_msat as i64;
 976                                                 }
 977                                         },
 978                                         _ => {},
 979                                 }
 980                         }
 981                 }
 982
 983                 let value_to_self_msat: i64 = (self.value_to_self_msat - local_htlc_total_msat) as i64 + value_to_self_msat_offset;
 984                 assert!(value_to_self_msat >= 0);
 985                 // Note that in case they have several just-awaiting-last-RAA fulfills in-progress (ie
 986                 // AwaitingRemoteRevokeToRemove or AwaitingRemovedRemoteRevoke) we may have allowed them to
 987                 // "violate" their reserve value by couting those against it. Thus, we have to convert
 988                 // everything to i64 before subtracting as otherwise we can overflow.
 989                 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;
 990                 assert!(value_to_remote_msat >= 0);
 991
 992                 #[cfg(debug_assertions)]
 993                 {
 994                         // Make sure that the to_self/to_remote is always either past the appropriate
 995                         // channel_reserve *or* it is making progress towards it.
 996                         let mut broadcaster_max_commitment_tx_output = if generated_by_local {
 997                                 self.holder_max_commitment_tx_output.lock().unwrap()
 998                         } else {
 999                                 self.counterparty_max_commitment_tx_output.lock().unwrap()
1000                         };
1001                         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 as i64);
1002                         broadcaster_max_commitment_tx_output.0 = cmp::max(broadcaster_max_commitment_tx_output.0, value_to_self_msat as u64);
1003                         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);
1004                         broadcaster_max_commitment_tx_output.1 = cmp::max(broadcaster_max_commitment_tx_output.1, value_to_remote_msat as u64);
1005                 }
1006
1007                 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;
1008                 let (value_to_self, value_to_remote) = if self.is_outbound() {
1009                         (value_to_self_msat / 1000 - total_fee as i64, value_to_remote_msat / 1000)
1010                 } else {
1011                         (value_to_self_msat / 1000, value_to_remote_msat / 1000 - total_fee as i64)
1012                 };
1013
1014                 let mut value_to_a = if local { value_to_self } else { value_to_remote };
1015                 let mut value_to_b = if local { value_to_remote } else { value_to_self };
1016
1017                 if value_to_a >= (broadcaster_dust_limit_satoshis as i64) {
1018                         log_trace!(logger, "   ...including {} output with value {}", if local { "to_local" } else { "to_remote" }, value_to_a);
1019                 } else {
1020                         value_to_a = 0;
1021                 }
1022
1023                 if value_to_b >= (broadcaster_dust_limit_satoshis as i64) {
1024                         log_trace!(logger, "   ...including {} output with value {}", if local { "to_remote" } else { "to_local" }, value_to_b);
1025                 } else {
1026                         value_to_b = 0;
1027                 }
1028
1029                 let num_nondust_htlcs = included_non_dust_htlcs.len();
1030
1031                 let channel_parameters =
1032                         if local { self.channel_transaction_parameters.as_holder_broadcastable() }
1033                         else { self.channel_transaction_parameters.as_counterparty_broadcastable() };
1034                 let tx = CommitmentTransaction::new_with_auxiliary_htlc_data(commitment_number,
1035                                                                              value_to_a as u64,
1036                                                                              value_to_b as u64,
1037                                                                              keys.clone(),
1038                                                                              feerate_per_kw,
1039                                                                              &mut included_non_dust_htlcs,
1040                                                                              &channel_parameters
1041                 );
1042                 let mut htlcs_included = included_non_dust_htlcs;
1043                 // The unwrap is safe, because all non-dust HTLCs have been assigned an output index
1044                 htlcs_included.sort_unstable_by_key(|h| h.0.transaction_output_index.unwrap());
1045                 htlcs_included.append(&mut included_dust_htlcs);
1046
1047                 (tx, num_nondust_htlcs, htlcs_included)
1048         }
1049
1050         #[inline]
1051         fn get_closing_scriptpubkey(&self) -> Script {
1052                 let channel_close_key_hash = WPubkeyHash::hash(&self.shutdown_pubkey.serialize());
1053                 Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&channel_close_key_hash[..]).into_script()
1054         }
1055
1056         #[inline]
1057         fn get_closing_transaction_weight(&self, a_scriptpubkey: Option<&Script>, b_scriptpubkey: Option<&Script>) -> u64 {
1058                 let mut ret =
1059                 (4 +                                           // version
1060                  1 +                                           // input count
1061                  36 +                                          // prevout
1062                  1 +                                           // script length (0)
1063                  4 +                                           // sequence
1064                  1 +                                           // output count
1065                  4                                             // lock time
1066                  )*4 +                                         // * 4 for non-witness parts
1067                 2 +                                            // witness marker and flag
1068                 1 +                                            // witness element count
1069                 4 +                                            // 4 element lengths (2 sigs, multisig dummy, and witness script)
1070                 self.get_funding_redeemscript().len() as u64 + // funding witness script
1071                 2*(1 + 71);                                    // two signatures + sighash type flags
1072                 if let Some(spk) = a_scriptpubkey {
1073                         ret += ((8+1) +                            // output values and script length
1074                                 spk.len() as u64) * 4;                 // scriptpubkey and witness multiplier
1075                 }
1076                 if let Some(spk) = b_scriptpubkey {
1077                         ret += ((8+1) +                            // output values and script length
1078                                 spk.len() as u64) * 4;                 // scriptpubkey and witness multiplier
1079                 }
1080                 ret
1081         }
1082
1083         #[inline]
1084         fn build_closing_transaction(&self, proposed_total_fee_satoshis: u64, skip_remote_output: bool) -> (Transaction, u64) {
1085                 let txins = {
1086                         let mut ins: Vec<TxIn> = Vec::new();
1087                         ins.push(TxIn {
1088                                 previous_output: self.funding_outpoint().into_bitcoin_outpoint(),
1089                                 script_sig: Script::new(),
1090                                 sequence: 0xffffffff,
1091                                 witness: Vec::new(),
1092                         });
1093                         ins
1094                 };
1095
1096                 assert!(self.pending_inbound_htlcs.is_empty());
1097                 assert!(self.pending_outbound_htlcs.is_empty());
1098                 let mut txouts: Vec<(TxOut, ())> = Vec::new();
1099
1100                 let mut total_fee_satoshis = proposed_total_fee_satoshis;
1101                 let value_to_self: i64 = (self.value_to_self_msat as i64) / 1000 - if self.is_outbound() { total_fee_satoshis as i64 } else { 0 };
1102                 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 };
1103
1104                 if value_to_self < 0 {
1105                         assert!(self.is_outbound());
1106                         total_fee_satoshis += (-value_to_self) as u64;
1107                 } else if value_to_remote < 0 {
1108                         assert!(!self.is_outbound());
1109                         total_fee_satoshis += (-value_to_remote) as u64;
1110                 }
1111
1112                 if !skip_remote_output && value_to_remote as u64 > self.holder_dust_limit_satoshis {
1113                         txouts.push((TxOut {
1114                                 script_pubkey: self.counterparty_shutdown_scriptpubkey.clone().unwrap(),
1115                                 value: value_to_remote as u64
1116                         }, ()));
1117                 }
1118
1119                 if value_to_self as u64 > self.holder_dust_limit_satoshis {
1120                         txouts.push((TxOut {
1121                                 script_pubkey: self.get_closing_scriptpubkey(),
1122                                 value: value_to_self as u64
1123                         }, ()));
1124                 }
1125
1126                 transaction_utils::sort_outputs(&mut txouts, |_, _| { cmp::Ordering::Equal }); // Ordering doesnt matter if they used our pubkey...
1127
1128                 let mut outputs: Vec<TxOut> = Vec::new();
1129                 for out in txouts.drain(..) {
1130                         outputs.push(out.0);
1131                 }
1132
1133                 (Transaction {
1134                         version: 2,
1135                         lock_time: 0,
1136                         input: txins,
1137                         output: outputs,
1138                 }, total_fee_satoshis)
1139         }
1140
1141         fn funding_outpoint(&self) -> OutPoint {
1142                 self.channel_transaction_parameters.funding_outpoint.unwrap()
1143         }
1144
1145         #[inline]
1146         /// Creates a set of keys for build_commitment_transaction to generate a transaction which our
1147         /// counterparty will sign (ie DO NOT send signatures over a transaction created by this to
1148         /// our counterparty!)
1149         /// The result is a transaction which we can revoke broadcastership of (ie a "local" transaction)
1150         /// TODO Some magic rust shit to compile-time check this?
1151         fn build_holder_transaction_keys(&self, commitment_number: u64) -> Result<TxCreationKeys, ChannelError> {
1152                 let per_commitment_point = self.holder_signer.get_per_commitment_point(commitment_number, &self.secp_ctx);
1153                 let delayed_payment_base = &self.get_holder_pubkeys().delayed_payment_basepoint;
1154                 let htlc_basepoint = &self.get_holder_pubkeys().htlc_basepoint;
1155                 let counterparty_pubkeys = self.get_counterparty_pubkeys();
1156
1157                 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()))
1158         }
1159
1160         #[inline]
1161         /// Creates a set of keys for build_commitment_transaction to generate a transaction which we
1162         /// will sign and send to our counterparty.
1163         /// If an Err is returned, it is a ChannelError::Close (for get_outbound_funding_created)
1164         fn build_remote_transaction_keys(&self) -> Result<TxCreationKeys, ChannelError> {
1165                 //TODO: Ensure that the payment_key derived here ends up in the library users' wallet as we
1166                 //may see payments to it!
1167                 let revocation_basepoint = &self.get_holder_pubkeys().revocation_basepoint;
1168                 let htlc_basepoint = &self.get_holder_pubkeys().htlc_basepoint;
1169                 let counterparty_pubkeys = self.get_counterparty_pubkeys();
1170
1171                 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()))
1172         }
1173
1174         /// Gets the redeemscript for the funding transaction output (ie the funding transaction output
1175         /// pays to get_funding_redeemscript().to_v0_p2wsh()).
1176         /// Panics if called before accept_channel/new_from_req
1177         pub fn get_funding_redeemscript(&self) -> Script {
1178                 make_funding_redeemscript(&self.get_holder_pubkeys().funding_pubkey, self.counterparty_funding_pubkey())
1179         }
1180
1181         /// Builds the htlc-success or htlc-timeout transaction which spends a given HTLC output
1182         /// @local is used only to convert relevant internal structures which refer to remote vs local
1183         /// to decide value of outputs and direction of HTLCs.
1184         fn build_htlc_transaction(&self, prev_hash: &Txid, htlc: &HTLCOutputInCommitment, local: bool, keys: &TxCreationKeys, feerate_per_kw: u32) -> Transaction {
1185                 chan_utils::build_htlc_transaction(prev_hash, feerate_per_kw, if local { self.get_counterparty_selected_contest_delay() } else { self.get_holder_selected_contest_delay() }, htlc, &keys.broadcaster_delayed_payment_key, &keys.revocation_key)
1186         }
1187
1188         /// Per HTLC, only one get_update_fail_htlc or get_update_fulfill_htlc call may be made.
1189         /// In such cases we debug_assert!(false) and return a ChannelError::Ignore. Thus, will always
1190         /// return Ok(_) if debug assertions are turned on or preconditions are met.
1191         ///
1192         /// Note that it is still possible to hit these assertions in case we find a preimage on-chain
1193         /// but then have a reorg which settles on an HTLC-failure on chain.
1194         fn get_update_fulfill_htlc<L: Deref>(&mut self, htlc_id_arg: u64, payment_preimage_arg: PaymentPreimage, logger: &L) -> Result<(Option<msgs::UpdateFulfillHTLC>, Option<ChannelMonitorUpdate>), ChannelError> where L::Target: Logger {
1195                 // Either ChannelFunded got set (which means it won't be unset) or there is no way any
1196                 // caller thought we could have something claimed (cause we wouldn't have accepted in an
1197                 // incoming HTLC anyway). If we got to ShutdownComplete, callers aren't allowed to call us,
1198                 // either.
1199                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
1200                         panic!("Was asked to fulfill an HTLC when channel was not in an operational state");
1201                 }
1202                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
1203
1204                 let payment_hash_calc = PaymentHash(Sha256::hash(&payment_preimage_arg.0[..]).into_inner());
1205
1206                 // ChannelManager may generate duplicate claims/fails due to HTLC update events from
1207                 // on-chain ChannelsMonitors during block rescan. Ideally we'd figure out a way to drop
1208                 // these, but for now we just have to treat them as normal.
1209
1210                 let mut pending_idx = std::usize::MAX;
1211                 for (idx, htlc) in self.pending_inbound_htlcs.iter().enumerate() {
1212                         if htlc.htlc_id == htlc_id_arg {
1213                                 assert_eq!(htlc.payment_hash, payment_hash_calc);
1214                                 match htlc.state {
1215                                         InboundHTLCState::Committed => {},
1216                                         InboundHTLCState::LocalRemoved(ref reason) => {
1217                                                 if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
1218                                                 } else {
1219                                                         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()));
1220                                                 }
1221                                                 debug_assert!(false, "Tried to fulfill an HTLC that was already fail/fulfilled");
1222                                                 return Ok((None, None));
1223                                         },
1224                                         _ => {
1225                                                 debug_assert!(false, "Have an inbound HTLC we tried to claim before it was fully committed to");
1226                                                 // Don't return in release mode here so that we can update channel_monitor
1227                                         }
1228                                 }
1229                                 pending_idx = idx;
1230                                 break;
1231                         }
1232                 }
1233                 if pending_idx == std::usize::MAX {
1234                         return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID".to_owned()));
1235                 }
1236
1237                 // Now update local state:
1238                 //
1239                 // We have to put the payment_preimage in the channel_monitor right away here to ensure we
1240                 // can claim it even if the channel hits the chain before we see their next commitment.
1241                 self.latest_monitor_update_id += 1;
1242                 let monitor_update = ChannelMonitorUpdate {
1243                         update_id: self.latest_monitor_update_id,
1244                         updates: vec![ChannelMonitorUpdateStep::PaymentPreimage {
1245                                 payment_preimage: payment_preimage_arg.clone(),
1246                         }],
1247                 };
1248
1249                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32)) != 0 {
1250                         for pending_update in self.holding_cell_htlc_updates.iter() {
1251                                 match pending_update {
1252                                         &HTLCUpdateAwaitingACK::ClaimHTLC { htlc_id, .. } => {
1253                                                 if htlc_id_arg == htlc_id {
1254                                                         // Make sure we don't leave latest_monitor_update_id incremented here:
1255                                                         self.latest_monitor_update_id -= 1;
1256                                                         debug_assert!(false, "Tried to fulfill an HTLC that was already fulfilled");
1257                                                         return Ok((None, None));
1258                                                 }
1259                                         },
1260                                         &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, .. } => {
1261                                                 if htlc_id_arg == htlc_id {
1262                                                         log_warn!(logger, "Have preimage and want to fulfill HTLC with pending failure against channel {}", log_bytes!(self.channel_id()));
1263                                                         // TODO: We may actually be able to switch to a fulfill here, though its
1264                                                         // rare enough it may not be worth the complexity burden.
1265                                                         debug_assert!(false, "Tried to fulfill an HTLC that was already failed");
1266                                                         return Ok((None, Some(monitor_update)));
1267                                                 }
1268                                         },
1269                                         _ => {}
1270                                 }
1271                         }
1272                         log_trace!(logger, "Adding HTLC claim to holding_cell! Current state: {}", self.channel_state);
1273                         self.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::ClaimHTLC {
1274                                 payment_preimage: payment_preimage_arg, htlc_id: htlc_id_arg,
1275                         });
1276                         return Ok((None, Some(monitor_update)));
1277                 }
1278
1279                 {
1280                         let htlc = &mut self.pending_inbound_htlcs[pending_idx];
1281                         if let InboundHTLCState::Committed = htlc.state {
1282                         } else {
1283                                 debug_assert!(false, "Have an inbound HTLC we tried to claim before it was fully committed to");
1284                                 return Ok((None, Some(monitor_update)));
1285                         }
1286                         log_trace!(logger, "Upgrading HTLC {} to LocalRemoved with a Fulfill!", log_bytes!(htlc.payment_hash.0));
1287                         htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::Fulfill(payment_preimage_arg.clone()));
1288                 }
1289
1290                 Ok((Some(msgs::UpdateFulfillHTLC {
1291                         channel_id: self.channel_id(),
1292                         htlc_id: htlc_id_arg,
1293                         payment_preimage: payment_preimage_arg,
1294                 }), Some(monitor_update)))
1295         }
1296
1297         pub fn get_update_fulfill_htlc_and_commit<L: Deref>(&mut self, htlc_id: u64, payment_preimage: PaymentPreimage, logger: &L) -> Result<(Option<(msgs::UpdateFulfillHTLC, msgs::CommitmentSigned)>, Option<ChannelMonitorUpdate>), ChannelError> where L::Target: Logger {
1298                 match self.get_update_fulfill_htlc(htlc_id, payment_preimage, logger)? {
1299                         (Some(update_fulfill_htlc), Some(mut monitor_update)) => {
1300                                 let (commitment, mut additional_update) = self.send_commitment_no_status_check(logger)?;
1301                                 // send_commitment_no_status_check may bump latest_monitor_id but we want them to be
1302                                 // strictly increasing by one, so decrement it here.
1303                                 self.latest_monitor_update_id = monitor_update.update_id;
1304                                 monitor_update.updates.append(&mut additional_update.updates);
1305                                 Ok((Some((update_fulfill_htlc, commitment)), Some(monitor_update)))
1306                         },
1307                         (Some(update_fulfill_htlc), None) => {
1308                                 let (commitment, monitor_update) = self.send_commitment_no_status_check(logger)?;
1309                                 Ok((Some((update_fulfill_htlc, commitment)), Some(monitor_update)))
1310                         },
1311                         (None, Some(monitor_update)) => Ok((None, Some(monitor_update))),
1312                         (None, None) => Ok((None, None))
1313                 }
1314         }
1315
1316         /// Per HTLC, only one get_update_fail_htlc or get_update_fulfill_htlc call may be made.
1317         /// In such cases we debug_assert!(false) and return a ChannelError::Ignore. Thus, will always
1318         /// return Ok(_) if debug assertions are turned on or preconditions are met.
1319         ///
1320         /// Note that it is still possible to hit these assertions in case we find a preimage on-chain
1321         /// but then have a reorg which settles on an HTLC-failure on chain.
1322         pub fn get_update_fail_htlc(&mut self, htlc_id_arg: u64, err_packet: msgs::OnionErrorPacket) -> Result<Option<msgs::UpdateFailHTLC>, ChannelError> {
1323                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
1324                         panic!("Was asked to fail an HTLC when channel was not in an operational state");
1325                 }
1326                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
1327
1328                 // ChannelManager may generate duplicate claims/fails due to HTLC update events from
1329                 // on-chain ChannelsMonitors during block rescan. Ideally we'd figure out a way to drop
1330                 // these, but for now we just have to treat them as normal.
1331
1332                 let mut pending_idx = std::usize::MAX;
1333                 for (idx, htlc) in self.pending_inbound_htlcs.iter().enumerate() {
1334                         if htlc.htlc_id == htlc_id_arg {
1335                                 match htlc.state {
1336                                         InboundHTLCState::Committed => {},
1337                                         InboundHTLCState::LocalRemoved(_) => {
1338                                                 debug_assert!(false, "Tried to fail an HTLC that was already fail/fulfilled");
1339                                                 return Ok(None);
1340                                         },
1341                                         _ => {
1342                                                 debug_assert!(false, "Have an inbound HTLC we tried to claim before it was fully committed to");
1343                                                 return Err(ChannelError::Ignore(format!("Unable to find a pending HTLC which matched the given HTLC ID ({})", htlc.htlc_id)));
1344                                         }
1345                                 }
1346                                 pending_idx = idx;
1347                         }
1348                 }
1349                 if pending_idx == std::usize::MAX {
1350                         return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID".to_owned()));
1351                 }
1352
1353                 // Now update local state:
1354                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32)) != 0 {
1355                         for pending_update in self.holding_cell_htlc_updates.iter() {
1356                                 match pending_update {
1357                                         &HTLCUpdateAwaitingACK::ClaimHTLC { htlc_id, .. } => {
1358                                                 if htlc_id_arg == htlc_id {
1359                                                         debug_assert!(false, "Tried to fail an HTLC that was already fulfilled");
1360                                                         return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID".to_owned()));
1361                                                 }
1362                                         },
1363                                         &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, .. } => {
1364                                                 if htlc_id_arg == htlc_id {
1365                                                         debug_assert!(false, "Tried to fail an HTLC that was already failed");
1366                                                         return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID".to_owned()));
1367                                                 }
1368                                         },
1369                                         _ => {}
1370                                 }
1371                         }
1372                         self.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::FailHTLC {
1373                                 htlc_id: htlc_id_arg,
1374                                 err_packet,
1375                         });
1376                         return Ok(None);
1377                 }
1378
1379                 {
1380                         let htlc = &mut self.pending_inbound_htlcs[pending_idx];
1381                         htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::FailRelay(err_packet.clone()));
1382                 }
1383
1384                 Ok(Some(msgs::UpdateFailHTLC {
1385                         channel_id: self.channel_id(),
1386                         htlc_id: htlc_id_arg,
1387                         reason: err_packet
1388                 }))
1389         }
1390
1391         // Message handlers:
1392
1393         pub fn accept_channel(&mut self, msg: &msgs::AcceptChannel, config: &UserConfig, their_features: InitFeatures) -> Result<(), ChannelError> {
1394                 // Check sanity of message fields:
1395                 if !self.is_outbound() {
1396                         return Err(ChannelError::Close("Got an accept_channel message from an inbound peer".to_owned()));
1397                 }
1398                 if self.channel_state != ChannelState::OurInitSent as u32 {
1399                         return Err(ChannelError::Close("Got an accept_channel message at a strange time".to_owned()));
1400                 }
1401                 if msg.dust_limit_satoshis > 21000000 * 100000000 {
1402                         return Err(ChannelError::Close(format!("Peer never wants payout outputs? dust_limit_satoshis was {}", msg.dust_limit_satoshis)));
1403                 }
1404                 if msg.channel_reserve_satoshis > self.channel_value_satoshis {
1405                         return Err(ChannelError::Close(format!("Bogus channel_reserve_satoshis ({}). Must not be greater than ({})", msg.channel_reserve_satoshis, self.channel_value_satoshis)));
1406                 }
1407                 if msg.dust_limit_satoshis > msg.channel_reserve_satoshis {
1408                         return Err(ChannelError::Close(format!("Bogus channel_reserve ({}) and dust_limit ({})", msg.channel_reserve_satoshis, msg.dust_limit_satoshis)));
1409                 }
1410                 if msg.channel_reserve_satoshis < self.holder_dust_limit_satoshis {
1411                         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)));
1412                 }
1413                 let remote_reserve = Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis);
1414                 if msg.dust_limit_satoshis > remote_reserve {
1415                         return Err(ChannelError::Close(format!("Dust limit ({}) is bigger than our channel reserve ({})", msg.dust_limit_satoshis, remote_reserve)));
1416                 }
1417                 let full_channel_value_msat = (self.channel_value_satoshis - msg.channel_reserve_satoshis) * 1000;
1418                 if msg.htlc_minimum_msat >= full_channel_value_msat {
1419                         return Err(ChannelError::Close(format!("Minimum htlc value ({}) is full channel value ({})", msg.htlc_minimum_msat, full_channel_value_msat)));
1420                 }
1421                 let max_delay_acceptable = u16::min(config.peer_channel_config_limits.their_to_self_delay, MAX_LOCAL_BREAKDOWN_TIMEOUT);
1422                 if msg.to_self_delay > max_delay_acceptable {
1423                         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)));
1424                 }
1425                 if msg.max_accepted_htlcs < 1 {
1426                         return Err(ChannelError::Close("0 max_accepted_htlcs makes for a useless channel".to_owned()));
1427                 }
1428                 if msg.max_accepted_htlcs > MAX_HTLCS {
1429                         return Err(ChannelError::Close(format!("max_accepted_htlcs was {}. It must not be larger than {}", msg.max_accepted_htlcs, MAX_HTLCS)));
1430                 }
1431
1432                 // Now check against optional parameters as set by config...
1433                 if msg.htlc_minimum_msat > config.peer_channel_config_limits.max_htlc_minimum_msat {
1434                         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)));
1435                 }
1436                 if msg.max_htlc_value_in_flight_msat < config.peer_channel_config_limits.min_max_htlc_value_in_flight_msat {
1437                         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)));
1438                 }
1439                 if msg.channel_reserve_satoshis > config.peer_channel_config_limits.max_channel_reserve_satoshis {
1440                         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)));
1441                 }
1442                 if msg.max_accepted_htlcs < config.peer_channel_config_limits.min_max_accepted_htlcs {
1443                         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)));
1444                 }
1445                 if msg.dust_limit_satoshis < config.peer_channel_config_limits.min_dust_limit_satoshis {
1446                         return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is less than the user specified limit ({})", msg.dust_limit_satoshis, config.peer_channel_config_limits.min_dust_limit_satoshis)));
1447                 }
1448                 if msg.dust_limit_satoshis > config.peer_channel_config_limits.max_dust_limit_satoshis {
1449                         return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is greater than the user specified limit ({})", msg.dust_limit_satoshis, config.peer_channel_config_limits.max_dust_limit_satoshis)));
1450                 }
1451                 if msg.minimum_depth > config.peer_channel_config_limits.max_minimum_depth {
1452                         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)));
1453                 }
1454
1455                 let counterparty_shutdown_scriptpubkey = if their_features.supports_upfront_shutdown_script() {
1456                         match &msg.shutdown_scriptpubkey {
1457                                 &OptionalField::Present(ref script) => {
1458                                         // Peer is signaling upfront_shutdown and has opt-out with a 0-length script. We don't enforce anything
1459                                         if script.len() == 0 {
1460                                                 None
1461                                         // Peer is signaling upfront_shutdown and has provided a non-accepted scriptpubkey format. Fail the channel
1462                                         } else if is_unsupported_shutdown_script(&their_features, script) {
1463                                                 return Err(ChannelError::Close(format!("Peer is signaling upfront_shutdown but has provided a non-accepted scriptpubkey format. script: ({})", script.to_bytes().to_hex())));
1464                                         } else {
1465                                                 Some(script.clone())
1466                                         }
1467                                 },
1468                                 // 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
1469                                 &OptionalField::Absent => {
1470                                         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()));
1471                                 }
1472                         }
1473                 } else { None };
1474
1475                 self.counterparty_dust_limit_satoshis = msg.dust_limit_satoshis;
1476                 self.counterparty_max_htlc_value_in_flight_msat = cmp::min(msg.max_htlc_value_in_flight_msat, self.channel_value_satoshis * 1000);
1477                 self.counterparty_selected_channel_reserve_satoshis = msg.channel_reserve_satoshis;
1478                 self.counterparty_htlc_minimum_msat = msg.htlc_minimum_msat;
1479                 self.counterparty_max_accepted_htlcs = msg.max_accepted_htlcs;
1480                 self.minimum_depth = msg.minimum_depth;
1481
1482                 let counterparty_pubkeys = ChannelPublicKeys {
1483                         funding_pubkey: msg.funding_pubkey,
1484                         revocation_basepoint: msg.revocation_basepoint,
1485                         payment_point: msg.payment_point,
1486                         delayed_payment_basepoint: msg.delayed_payment_basepoint,
1487                         htlc_basepoint: msg.htlc_basepoint
1488                 };
1489
1490                 self.channel_transaction_parameters.counterparty_parameters = Some(CounterpartyChannelTransactionParameters {
1491                         selected_contest_delay: msg.to_self_delay,
1492                         pubkeys: counterparty_pubkeys,
1493                 });
1494
1495                 self.counterparty_cur_commitment_point = Some(msg.first_per_commitment_point);
1496                 self.counterparty_shutdown_scriptpubkey = counterparty_shutdown_scriptpubkey;
1497
1498                 self.channel_state = ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32;
1499
1500                 Ok(())
1501         }
1502
1503         fn funding_created_signature<L: Deref>(&mut self, sig: &Signature, logger: &L) -> Result<(Txid, CommitmentTransaction, Signature), ChannelError> where L::Target: Logger {
1504                 let funding_script = self.get_funding_redeemscript();
1505
1506                 let keys = self.build_holder_transaction_keys(self.cur_holder_commitment_transaction_number)?;
1507                 let initial_commitment_tx = self.build_commitment_transaction(self.cur_holder_commitment_transaction_number, &keys, true, false, self.feerate_per_kw, logger).0;
1508                 {
1509                         let trusted_tx = initial_commitment_tx.trust();
1510                         let initial_commitment_bitcoin_tx = trusted_tx.built_transaction();
1511                         let sighash = initial_commitment_bitcoin_tx.get_sighash_all(&funding_script, self.channel_value_satoshis);
1512                         // They sign the holder commitment transaction...
1513                         log_trace!(logger, "Checking funding_created tx signature {} by key {} against tx {} (sighash {}) with redeemscript {}", log_bytes!(sig.serialize_compact()[..]), log_bytes!(self.counterparty_funding_pubkey().serialize()), encode::serialize_hex(&initial_commitment_bitcoin_tx.transaction), log_bytes!(sighash[..]), encode::serialize_hex(&funding_script));
1514                         secp_check!(self.secp_ctx.verify(&sighash, &sig, self.counterparty_funding_pubkey()), "Invalid funding_created signature from peer".to_owned());
1515                 }
1516
1517                 let counterparty_keys = self.build_remote_transaction_keys()?;
1518                 let counterparty_initial_commitment_tx = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, false, self.feerate_per_kw, logger).0;
1519
1520                 let counterparty_trusted_tx = counterparty_initial_commitment_tx.trust();
1521                 let counterparty_initial_bitcoin_tx = counterparty_trusted_tx.built_transaction();
1522                 log_trace!(logger, "Initial counterparty ID {} tx {}", counterparty_initial_bitcoin_tx.txid, encode::serialize_hex(&counterparty_initial_bitcoin_tx.transaction));
1523
1524                 let counterparty_signature = self.holder_signer.sign_counterparty_commitment(&counterparty_initial_commitment_tx, &self.secp_ctx)
1525                                 .map_err(|_| ChannelError::Close("Failed to get signatures for new commitment_signed".to_owned()))?.0;
1526
1527                 // We sign "counterparty" commitment transaction, allowing them to broadcast the tx if they wish.
1528                 Ok((counterparty_initial_bitcoin_tx.txid, initial_commitment_tx, counterparty_signature))
1529         }
1530
1531         fn counterparty_funding_pubkey(&self) -> &PublicKey {
1532                 &self.get_counterparty_pubkeys().funding_pubkey
1533         }
1534
1535         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 {
1536                 if self.is_outbound() {
1537                         return Err(ChannelError::Close("Received funding_created for an outbound channel?".to_owned()));
1538                 }
1539                 if self.channel_state != (ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32) {
1540                         // BOLT 2 says that if we disconnect before we send funding_signed we SHOULD NOT
1541                         // remember the channel, so it's safe to just send an error_message here and drop the
1542                         // channel.
1543                         return Err(ChannelError::Close("Received funding_created after we got the channel!".to_owned()));
1544                 }
1545                 if self.commitment_secrets.get_min_seen_secret() != (1 << 48) ||
1546                                 self.cur_counterparty_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER ||
1547                                 self.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
1548                         panic!("Should not have advanced channel commitment tx numbers prior to funding_created");
1549                 }
1550
1551                 let funding_txo = OutPoint { txid: msg.funding_txid, index: msg.funding_output_index };
1552                 self.channel_transaction_parameters.funding_outpoint = Some(funding_txo);
1553                 // This is an externally observable change before we finish all our checks.  In particular
1554                 // funding_created_signature may fail.
1555                 self.holder_signer.ready_channel(&self.channel_transaction_parameters);
1556
1557                 let (counterparty_initial_commitment_txid, initial_commitment_tx, signature) = match self.funding_created_signature(&msg.signature, logger) {
1558                         Ok(res) => res,
1559                         Err(ChannelError::Close(e)) => {
1560                                 self.channel_transaction_parameters.funding_outpoint = None;
1561                                 return Err(ChannelError::Close(e));
1562                         },
1563                         Err(e) => {
1564                                 // The only error we know how to handle is ChannelError::Close, so we fall over here
1565                                 // to make sure we don't continue with an inconsistent state.
1566                                 panic!("unexpected error type from funding_created_signature {:?}", e);
1567                         }
1568                 };
1569
1570                 let holder_commitment_tx = HolderCommitmentTransaction::new(
1571                         initial_commitment_tx,
1572                         msg.signature,
1573                         Vec::new(),
1574                         &self.get_holder_pubkeys().funding_pubkey,
1575                         self.counterparty_funding_pubkey()
1576                 );
1577
1578                 // Now that we're past error-generating stuff, update our local state:
1579
1580                 let funding_redeemscript = self.get_funding_redeemscript();
1581                 let funding_txo_script = funding_redeemscript.to_v0_p2wsh();
1582                 let obscure_factor = get_commitment_transaction_number_obscure_factor(&self.get_holder_pubkeys().payment_point, &self.get_counterparty_pubkeys().payment_point, self.is_outbound());
1583                 let channel_monitor = ChannelMonitor::new(self.secp_ctx.clone(), self.holder_signer.clone(),
1584                                                           &self.shutdown_pubkey, self.get_holder_selected_contest_delay(),
1585                                                           &self.destination_script, (funding_txo, funding_txo_script.clone()),
1586                                                           &self.channel_transaction_parameters,
1587                                                           funding_redeemscript.clone(), self.channel_value_satoshis,
1588                                                           obscure_factor,
1589                                                           holder_commitment_tx, best_block);
1590
1591                 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);
1592
1593                 self.channel_state = ChannelState::FundingSent as u32;
1594                 self.channel_id = funding_txo.to_channel_id();
1595                 self.cur_counterparty_commitment_transaction_number -= 1;
1596                 self.cur_holder_commitment_transaction_number -= 1;
1597
1598                 Ok((msgs::FundingSigned {
1599                         channel_id: self.channel_id,
1600                         signature
1601                 }, channel_monitor))
1602         }
1603
1604         /// Handles a funding_signed message from the remote end.
1605         /// If this call is successful, broadcast the funding transaction (and not before!)
1606         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 {
1607                 if !self.is_outbound() {
1608                         return Err(ChannelError::Close("Received funding_signed for an inbound channel?".to_owned()));
1609                 }
1610                 if self.channel_state & !(ChannelState::MonitorUpdateFailed as u32) != ChannelState::FundingCreated as u32 {
1611                         return Err(ChannelError::Close("Received funding_signed in strange state!".to_owned()));
1612                 }
1613                 if self.commitment_secrets.get_min_seen_secret() != (1 << 48) ||
1614                                 self.cur_counterparty_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER ||
1615                                 self.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
1616                         panic!("Should not have advanced channel commitment tx numbers prior to funding_created");
1617                 }
1618
1619                 let funding_script = self.get_funding_redeemscript();
1620
1621                 let counterparty_keys = self.build_remote_transaction_keys()?;
1622                 let counterparty_initial_commitment_tx = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, false, self.feerate_per_kw, logger).0;
1623                 let counterparty_trusted_tx = counterparty_initial_commitment_tx.trust();
1624                 let counterparty_initial_bitcoin_tx = counterparty_trusted_tx.built_transaction();
1625
1626                 log_trace!(logger, "Initial counterparty ID {} tx {}", counterparty_initial_bitcoin_tx.txid, encode::serialize_hex(&counterparty_initial_bitcoin_tx.transaction));
1627
1628                 let holder_signer = self.build_holder_transaction_keys(self.cur_holder_commitment_transaction_number)?;
1629                 let initial_commitment_tx = self.build_commitment_transaction(self.cur_holder_commitment_transaction_number, &holder_signer, true, false, self.feerate_per_kw, logger).0;
1630                 {
1631                         let trusted_tx = initial_commitment_tx.trust();
1632                         let initial_commitment_bitcoin_tx = trusted_tx.built_transaction();
1633                         let sighash = initial_commitment_bitcoin_tx.get_sighash_all(&funding_script, self.channel_value_satoshis);
1634                         // They sign our commitment transaction, allowing us to broadcast the tx if we wish.
1635                         if let Err(_) = self.secp_ctx.verify(&sighash, &msg.signature, &self.get_counterparty_pubkeys().funding_pubkey) {
1636                                 return Err(ChannelError::Close("Invalid funding_signed signature from peer".to_owned()));
1637                         }
1638                 }
1639
1640                 let holder_commitment_tx = HolderCommitmentTransaction::new(
1641                         initial_commitment_tx,
1642                         msg.signature,
1643                         Vec::new(),
1644                         &self.get_holder_pubkeys().funding_pubkey,
1645                         self.counterparty_funding_pubkey()
1646                 );
1647
1648
1649                 let funding_redeemscript = self.get_funding_redeemscript();
1650                 let funding_txo = self.get_funding_txo().unwrap();
1651                 let funding_txo_script = funding_redeemscript.to_v0_p2wsh();
1652                 let obscure_factor = get_commitment_transaction_number_obscure_factor(&self.get_holder_pubkeys().payment_point, &self.get_counterparty_pubkeys().payment_point, self.is_outbound());
1653                 let channel_monitor = ChannelMonitor::new(self.secp_ctx.clone(), self.holder_signer.clone(),
1654                                                           &self.shutdown_pubkey, self.get_holder_selected_contest_delay(),
1655                                                           &self.destination_script, (funding_txo, funding_txo_script),
1656                                                           &self.channel_transaction_parameters,
1657                                                           funding_redeemscript.clone(), self.channel_value_satoshis,
1658                                                           obscure_factor,
1659                                                           holder_commitment_tx, best_block);
1660
1661                 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);
1662
1663                 assert_eq!(self.channel_state & (ChannelState::MonitorUpdateFailed as u32), 0); // We have no had any monitor(s) yet to fail update!
1664                 self.channel_state = ChannelState::FundingSent as u32;
1665                 self.cur_holder_commitment_transaction_number -= 1;
1666                 self.cur_counterparty_commitment_transaction_number -= 1;
1667
1668                 Ok((channel_monitor, self.funding_transaction.as_ref().cloned().unwrap()))
1669         }
1670
1671         pub fn funding_locked(&mut self, msg: &msgs::FundingLocked) -> Result<(), ChannelError> {
1672                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
1673                         return Err(ChannelError::Close("Peer sent funding_locked when we needed a channel_reestablish".to_owned()));
1674                 }
1675
1676                 let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
1677
1678                 if non_shutdown_state == ChannelState::FundingSent as u32 {
1679                         self.channel_state |= ChannelState::TheirFundingLocked as u32;
1680                 } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::OurFundingLocked as u32) {
1681                         self.channel_state = ChannelState::ChannelFunded as u32 | (self.channel_state & MULTI_STATE_FLAGS);
1682                         self.update_time_counter += 1;
1683                 } else if (self.channel_state & (ChannelState::ChannelFunded as u32) != 0 &&
1684                                  // Note that funding_signed/funding_created will have decremented both by 1!
1685                                  self.cur_holder_commitment_transaction_number == INITIAL_COMMITMENT_NUMBER - 1 &&
1686                                  self.cur_counterparty_commitment_transaction_number == INITIAL_COMMITMENT_NUMBER - 1) ||
1687                                 // If we reconnected before sending our funding locked they may still resend theirs:
1688                                 (self.channel_state & (ChannelState::FundingSent as u32 | ChannelState::TheirFundingLocked as u32) ==
1689                                                       (ChannelState::FundingSent as u32 | ChannelState::TheirFundingLocked as u32)) {
1690                         if self.counterparty_cur_commitment_point != Some(msg.next_per_commitment_point) {
1691                                 return Err(ChannelError::Close("Peer sent a reconnect funding_locked with a different point".to_owned()));
1692                         }
1693                         // They probably disconnected/reconnected and re-sent the funding_locked, which is required
1694                         return Ok(());
1695                 } else {
1696                         return Err(ChannelError::Close("Peer sent a funding_locked at a strange time".to_owned()));
1697                 }
1698
1699                 self.counterparty_prev_commitment_point = self.counterparty_cur_commitment_point;
1700                 self.counterparty_cur_commitment_point = Some(msg.next_per_commitment_point);
1701                 Ok(())
1702         }
1703
1704         /// Returns (inbound_htlc_count, htlc_inbound_value_msat)
1705         fn get_inbound_pending_htlc_stats(&self) -> (u32, u64) {
1706                 let mut htlc_inbound_value_msat = 0;
1707                 for ref htlc in self.pending_inbound_htlcs.iter() {
1708                         htlc_inbound_value_msat += htlc.amount_msat;
1709                 }
1710                 (self.pending_inbound_htlcs.len() as u32, htlc_inbound_value_msat)
1711         }
1712
1713         /// Returns (outbound_htlc_count, htlc_outbound_value_msat) *including* pending adds in our
1714         /// holding cell.
1715         fn get_outbound_pending_htlc_stats(&self) -> (u32, u64) {
1716                 let mut htlc_outbound_value_msat = 0;
1717                 for ref htlc in self.pending_outbound_htlcs.iter() {
1718                         htlc_outbound_value_msat += htlc.amount_msat;
1719                 }
1720
1721                 let mut htlc_outbound_count = self.pending_outbound_htlcs.len();
1722                 for update in self.holding_cell_htlc_updates.iter() {
1723                         if let &HTLCUpdateAwaitingACK::AddHTLC { ref amount_msat, .. } = update {
1724                                 htlc_outbound_count += 1;
1725                                 htlc_outbound_value_msat += amount_msat;
1726                         }
1727                 }
1728
1729                 (htlc_outbound_count as u32, htlc_outbound_value_msat)
1730         }
1731
1732         /// Get the available (ie not including pending HTLCs) inbound and outbound balance in msat.
1733         /// Doesn't bother handling the
1734         /// if-we-removed-it-already-but-haven't-fully-resolved-they-can-still-send-an-inbound-HTLC
1735         /// corner case properly.
1736         pub fn get_inbound_outbound_available_balance_msat(&self) -> (u64, u64) {
1737                 // Note that we have to handle overflow due to the above case.
1738                 (cmp::max(self.channel_value_satoshis as i64 * 1000 - self.value_to_self_msat as i64 - self.get_inbound_pending_htlc_stats().1 as i64, 0) as u64,
1739                 cmp::max(self.value_to_self_msat as i64 - self.get_outbound_pending_htlc_stats().1 as i64, 0) as u64)
1740         }
1741
1742         // Get the fee cost of a commitment tx with a given number of HTLC outputs.
1743         // Note that num_htlcs should not include dust HTLCs.
1744         fn commit_tx_fee_msat(&self, num_htlcs: usize) -> u64 {
1745                 // Note that we need to divide before multiplying to round properly,
1746                 // since the lowest denomination of bitcoin on-chain is the satoshi.
1747                 (COMMITMENT_TX_BASE_WEIGHT + num_htlcs as u64 * COMMITMENT_TX_WEIGHT_PER_HTLC) * self.feerate_per_kw as u64 / 1000 * 1000
1748         }
1749
1750         // Get the commitment tx fee for the local's (i.e. our) next commitment transaction based on the
1751         // number of pending HTLCs that are on track to be in our next commitment tx, plus an additional
1752         // HTLC if `fee_spike_buffer_htlc` is Some, plus a new HTLC given by `new_htlc_amount`. Dust HTLCs
1753         // are excluded.
1754         fn next_local_commit_tx_fee_msat(&self, htlc: HTLCCandidate, fee_spike_buffer_htlc: Option<()>) -> u64 {
1755                 assert!(self.is_outbound());
1756
1757                 let real_dust_limit_success_sat = (self.feerate_per_kw as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) + self.holder_dust_limit_satoshis;
1758                 let real_dust_limit_timeout_sat = (self.feerate_per_kw as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + self.holder_dust_limit_satoshis;
1759
1760                 let mut addl_htlcs = 0;
1761                 if fee_spike_buffer_htlc.is_some() { addl_htlcs += 1; }
1762                 match htlc.origin {
1763                         HTLCInitiator::LocalOffered => {
1764                                 if htlc.amount_msat / 1000 >= real_dust_limit_timeout_sat {
1765                                         addl_htlcs += 1;
1766                                 }
1767                         },
1768                         HTLCInitiator::RemoteOffered => {
1769                                 if htlc.amount_msat / 1000 >= real_dust_limit_success_sat {
1770                                         addl_htlcs += 1;
1771                                 }
1772                         }
1773                 }
1774
1775                 let mut included_htlcs = 0;
1776                 for ref htlc in self.pending_inbound_htlcs.iter() {
1777                         if htlc.amount_msat / 1000 < real_dust_limit_success_sat {
1778                                 continue
1779                         }
1780                         // We include LocalRemoved HTLCs here because we may still need to broadcast a commitment
1781                         // transaction including this HTLC if it times out before they RAA.
1782                         included_htlcs += 1;
1783                 }
1784
1785                 for ref htlc in self.pending_outbound_htlcs.iter() {
1786                         if htlc.amount_msat / 1000 < real_dust_limit_timeout_sat {
1787                                 continue
1788                         }
1789                         match htlc.state {
1790                                 OutboundHTLCState::LocalAnnounced {..} => included_htlcs += 1,
1791                                 OutboundHTLCState::Committed => included_htlcs += 1,
1792                                 OutboundHTLCState::RemoteRemoved {..} => included_htlcs += 1,
1793                                 // We don't include AwaitingRemoteRevokeToRemove HTLCs because our next commitment
1794                                 // transaction won't be generated until they send us their next RAA, which will mean
1795                                 // dropping any HTLCs in this state.
1796                                 _ => {},
1797                         }
1798                 }
1799
1800                 for htlc in self.holding_cell_htlc_updates.iter() {
1801                         match htlc {
1802                                 &HTLCUpdateAwaitingACK::AddHTLC { amount_msat, .. } => {
1803                                         if amount_msat / 1000 < real_dust_limit_timeout_sat {
1804                                                 continue
1805                                         }
1806                                         included_htlcs += 1
1807                                 },
1808                                 _ => {}, // Don't include claims/fails that are awaiting ack, because once we get the
1809                                          // ack we're guaranteed to never include them in commitment txs anymore.
1810                         }
1811                 }
1812
1813                 let num_htlcs = included_htlcs + addl_htlcs;
1814                 let res = self.commit_tx_fee_msat(num_htlcs);
1815                 #[cfg(any(test, feature = "fuzztarget"))]
1816                 {
1817                         let mut fee = res;
1818                         if fee_spike_buffer_htlc.is_some() {
1819                                 fee = self.commit_tx_fee_msat(num_htlcs - 1);
1820                         }
1821                         let total_pending_htlcs = self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len()
1822                                 + self.holding_cell_htlc_updates.len();
1823                         let commitment_tx_info = CommitmentTxInfoCached {
1824                                 fee,
1825                                 total_pending_htlcs,
1826                                 next_holder_htlc_id: match htlc.origin {
1827                                         HTLCInitiator::LocalOffered => self.next_holder_htlc_id + 1,
1828                                         HTLCInitiator::RemoteOffered => self.next_holder_htlc_id,
1829                                 },
1830                                 next_counterparty_htlc_id: match htlc.origin {
1831                                         HTLCInitiator::LocalOffered => self.next_counterparty_htlc_id,
1832                                         HTLCInitiator::RemoteOffered => self.next_counterparty_htlc_id + 1,
1833                                 },
1834                                 feerate: self.feerate_per_kw,
1835                         };
1836                         *self.next_local_commitment_tx_fee_info_cached.lock().unwrap() = Some(commitment_tx_info);
1837                 }
1838                 res
1839         }
1840
1841         // Get the commitment tx fee for the remote's next commitment transaction based on the number of
1842         // pending HTLCs that are on track to be in their next commitment tx, plus an additional HTLC if
1843         // `fee_spike_buffer_htlc` is Some, plus a new HTLC given by `new_htlc_amount`. Dust HTLCs are
1844         // excluded.
1845         fn next_remote_commit_tx_fee_msat(&self, htlc: HTLCCandidate, fee_spike_buffer_htlc: Option<()>) -> u64 {
1846                 assert!(!self.is_outbound());
1847
1848                 let real_dust_limit_success_sat = (self.feerate_per_kw as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) + self.counterparty_dust_limit_satoshis;
1849                 let real_dust_limit_timeout_sat = (self.feerate_per_kw as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + self.counterparty_dust_limit_satoshis;
1850
1851                 let mut addl_htlcs = 0;
1852                 if fee_spike_buffer_htlc.is_some() { addl_htlcs += 1; }
1853                 match htlc.origin {
1854                         HTLCInitiator::LocalOffered => {
1855                                 if htlc.amount_msat / 1000 >= real_dust_limit_success_sat {
1856                                         addl_htlcs += 1;
1857                                 }
1858                         },
1859                         HTLCInitiator::RemoteOffered => {
1860                                 if htlc.amount_msat / 1000 >= real_dust_limit_timeout_sat {
1861                                         addl_htlcs += 1;
1862                                 }
1863                         }
1864                 }
1865
1866                 // When calculating the set of HTLCs which will be included in their next commitment_signed, all
1867                 // non-dust inbound HTLCs are included (as all states imply it will be included) and only
1868                 // committed outbound HTLCs, see below.
1869                 let mut included_htlcs = 0;
1870                 for ref htlc in self.pending_inbound_htlcs.iter() {
1871                         if htlc.amount_msat / 1000 <= real_dust_limit_timeout_sat {
1872                                 continue
1873                         }
1874                         included_htlcs += 1;
1875                 }
1876
1877                 for ref htlc in self.pending_outbound_htlcs.iter() {
1878                         if htlc.amount_msat / 1000 <= real_dust_limit_success_sat {
1879                                 continue
1880                         }
1881                         // We only include outbound HTLCs if it will not be included in their next commitment_signed,
1882                         // i.e. if they've responded to us with an RAA after announcement.
1883                         match htlc.state {
1884                                 OutboundHTLCState::Committed => included_htlcs += 1,
1885                                 OutboundHTLCState::RemoteRemoved {..} => included_htlcs += 1,
1886                                 OutboundHTLCState::LocalAnnounced { .. } => included_htlcs += 1,
1887                                 _ => {},
1888                         }
1889                 }
1890
1891                 let num_htlcs = included_htlcs + addl_htlcs;
1892                 let res = self.commit_tx_fee_msat(num_htlcs);
1893                 #[cfg(any(test, feature = "fuzztarget"))]
1894                 {
1895                         let mut fee = res;
1896                         if fee_spike_buffer_htlc.is_some() {
1897                                 fee = self.commit_tx_fee_msat(num_htlcs - 1);
1898                         }
1899                         let total_pending_htlcs = self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len();
1900                         let commitment_tx_info = CommitmentTxInfoCached {
1901                                 fee,
1902                                 total_pending_htlcs,
1903                                 next_holder_htlc_id: match htlc.origin {
1904                                         HTLCInitiator::LocalOffered => self.next_holder_htlc_id + 1,
1905                                         HTLCInitiator::RemoteOffered => self.next_holder_htlc_id,
1906                                 },
1907                                 next_counterparty_htlc_id: match htlc.origin {
1908                                         HTLCInitiator::LocalOffered => self.next_counterparty_htlc_id,
1909                                         HTLCInitiator::RemoteOffered => self.next_counterparty_htlc_id + 1,
1910                                 },
1911                                 feerate: self.feerate_per_kw,
1912                         };
1913                         *self.next_remote_commitment_tx_fee_info_cached.lock().unwrap() = Some(commitment_tx_info);
1914                 }
1915                 res
1916         }
1917
1918         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>
1919         where F: for<'a> Fn(&'a Self, PendingHTLCStatus, u16) -> PendingHTLCStatus, L::Target: Logger {
1920                 // We can't accept HTLCs sent after we've sent a shutdown.
1921                 let local_sent_shutdown = (self.channel_state & (ChannelState::ChannelFunded as u32 | ChannelState::LocalShutdownSent as u32)) != (ChannelState::ChannelFunded as u32);
1922                 if local_sent_shutdown {
1923                         pending_forward_status = create_pending_htlc_status(self, pending_forward_status, 0x1000|20);
1924                 }
1925                 // If the remote has sent a shutdown prior to adding this HTLC, then they are in violation of the spec.
1926                 let remote_sent_shutdown = (self.channel_state & (ChannelState::ChannelFunded as u32 | ChannelState::RemoteShutdownSent as u32)) != (ChannelState::ChannelFunded as u32);
1927                 if remote_sent_shutdown {
1928                         return Err(ChannelError::Close("Got add HTLC message when channel was not in an operational state".to_owned()));
1929                 }
1930                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
1931                         return Err(ChannelError::Close("Peer sent update_add_htlc when we needed a channel_reestablish".to_owned()));
1932                 }
1933                 if msg.amount_msat > self.channel_value_satoshis * 1000 {
1934                         return Err(ChannelError::Close("Remote side tried to send more than the total value of the channel".to_owned()));
1935                 }
1936                 if msg.amount_msat == 0 {
1937                         return Err(ChannelError::Close("Remote side tried to send a 0-msat HTLC".to_owned()));
1938                 }
1939                 if msg.amount_msat < self.holder_htlc_minimum_msat {
1940                         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)));
1941                 }
1942
1943                 let (inbound_htlc_count, htlc_inbound_value_msat) = self.get_inbound_pending_htlc_stats();
1944                 if inbound_htlc_count + 1 > OUR_MAX_HTLCS as u32 {
1945                         return Err(ChannelError::Close(format!("Remote tried to push more than our max accepted HTLCs ({})", OUR_MAX_HTLCS)));
1946                 }
1947                 let holder_max_htlc_value_in_flight_msat = Channel::<Signer>::get_holder_max_htlc_value_in_flight_msat(self.channel_value_satoshis);
1948                 if htlc_inbound_value_msat + msg.amount_msat > holder_max_htlc_value_in_flight_msat {
1949                         return Err(ChannelError::Close(format!("Remote HTLC add would put them over our max HTLC value ({})", holder_max_htlc_value_in_flight_msat)));
1950                 }
1951                 // Check holder_selected_channel_reserve_satoshis (we're getting paid, so they have to at least meet
1952                 // the reserve_satoshis we told them to always have as direct payment so that they lose
1953                 // something if we punish them for broadcasting an old state).
1954                 // Note that we don't really care about having a small/no to_remote output in our local
1955                 // commitment transactions, as the purpose of the channel reserve is to ensure we can
1956                 // punish *them* if they misbehave, so we discount any outbound HTLCs which will not be
1957                 // present in the next commitment transaction we send them (at least for fulfilled ones,
1958                 // failed ones won't modify value_to_self).
1959                 // Note that we will send HTLCs which another instance of rust-lightning would think
1960                 // violate the reserve value if we do not do this (as we forget inbound HTLCs from the
1961                 // Channel state once they will not be present in the next received commitment
1962                 // transaction).
1963                 let mut removed_outbound_total_msat = 0;
1964                 for ref htlc in self.pending_outbound_htlcs.iter() {
1965                         if let OutboundHTLCState::AwaitingRemoteRevokeToRemove(None) = htlc.state {
1966                                 removed_outbound_total_msat += htlc.amount_msat;
1967                         } else if let OutboundHTLCState::AwaitingRemovedRemoteRevoke(None) = htlc.state {
1968                                 removed_outbound_total_msat += htlc.amount_msat;
1969                         }
1970                 }
1971
1972                 let pending_value_to_self_msat =
1973                         self.value_to_self_msat + htlc_inbound_value_msat - removed_outbound_total_msat;
1974                 let pending_remote_value_msat =
1975                         self.channel_value_satoshis * 1000 - pending_value_to_self_msat;
1976                 if pending_remote_value_msat < msg.amount_msat {
1977                         return Err(ChannelError::Close("Remote HTLC add would overdraw remaining funds".to_owned()));
1978                 }
1979
1980                 // Check that the remote can afford to pay for this HTLC on-chain at the current
1981                 // feerate_per_kw, while maintaining their channel reserve (as required by the spec).
1982                 let remote_commit_tx_fee_msat = if self.is_outbound() { 0 } else {
1983                         let htlc_candidate = HTLCCandidate::new(msg.amount_msat, HTLCInitiator::RemoteOffered);
1984                         self.next_remote_commit_tx_fee_msat(htlc_candidate, None) // Don't include the extra fee spike buffer HTLC in calculations
1985                 };
1986                 if pending_remote_value_msat - msg.amount_msat < remote_commit_tx_fee_msat {
1987                         return Err(ChannelError::Close("Remote HTLC add would not leave enough to pay for fees".to_owned()));
1988                 };
1989
1990                 let chan_reserve_msat =
1991                         Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis) * 1000;
1992                 if pending_remote_value_msat - msg.amount_msat - remote_commit_tx_fee_msat < chan_reserve_msat {
1993                         return Err(ChannelError::Close("Remote HTLC add would put them under remote reserve value".to_owned()));
1994                 }
1995
1996                 if !self.is_outbound() {
1997                         // `2 *` and `Some(())` is for the fee spike buffer we keep for the remote. This deviates from
1998                         // the spec because in the spec, the fee spike buffer requirement doesn't exist on the
1999                         // receiver's side, only on the sender's.
2000                         // Note that when we eventually remove support for fee updates and switch to anchor output
2001                         // fees, we will drop the `2 *`, since we no longer be as sensitive to fee spikes. But, keep
2002                         // the extra htlc when calculating the next remote commitment transaction fee as we should
2003                         // still be able to afford adding this HTLC plus one more future HTLC, regardless of being
2004                         // sensitive to fee spikes.
2005                         let htlc_candidate = HTLCCandidate::new(msg.amount_msat, HTLCInitiator::RemoteOffered);
2006                         let remote_fee_cost_incl_stuck_buffer_msat = 2 * self.next_remote_commit_tx_fee_msat(htlc_candidate, Some(()));
2007                         if pending_remote_value_msat - msg.amount_msat - chan_reserve_msat < remote_fee_cost_incl_stuck_buffer_msat {
2008                                 // Note that if the pending_forward_status is not updated here, then it's because we're already failing
2009                                 // the HTLC, i.e. its status is already set to failing.
2010                                 log_info!(logger, "Attempting to fail HTLC due to fee spike buffer violation");
2011                                 pending_forward_status = create_pending_htlc_status(self, pending_forward_status, 0x1000|7);
2012                         }
2013                 } else {
2014                         // Check that they won't violate our local required channel reserve by adding this HTLC.
2015                         let htlc_candidate = HTLCCandidate::new(msg.amount_msat, HTLCInitiator::RemoteOffered);
2016                         let local_commit_tx_fee_msat = self.next_local_commit_tx_fee_msat(htlc_candidate, None);
2017                         if self.value_to_self_msat < self.counterparty_selected_channel_reserve_satoshis * 1000 + local_commit_tx_fee_msat {
2018                                 return Err(ChannelError::Close("Cannot accept HTLC that would put our balance under counterparty-announced channel reserve value".to_owned()));
2019                         }
2020                 }
2021                 if self.next_counterparty_htlc_id != msg.htlc_id {
2022                         return Err(ChannelError::Close(format!("Remote skipped HTLC ID (skipped ID: {})", self.next_counterparty_htlc_id)));
2023                 }
2024                 if msg.cltv_expiry >= 500000000 {
2025                         return Err(ChannelError::Close("Remote provided CLTV expiry in seconds instead of block height".to_owned()));
2026                 }
2027
2028                 if self.channel_state & ChannelState::LocalShutdownSent as u32 != 0 {
2029                         if let PendingHTLCStatus::Forward(_) = pending_forward_status {
2030                                 panic!("ChannelManager shouldn't be trying to add a forwardable HTLC after we've started closing");
2031                         }
2032                 }
2033
2034                 // Now update local state:
2035                 self.next_counterparty_htlc_id += 1;
2036                 self.pending_inbound_htlcs.push(InboundHTLCOutput {
2037                         htlc_id: msg.htlc_id,
2038                         amount_msat: msg.amount_msat,
2039                         payment_hash: msg.payment_hash,
2040                         cltv_expiry: msg.cltv_expiry,
2041                         state: InboundHTLCState::RemoteAnnounced(pending_forward_status),
2042                 });
2043                 Ok(())
2044         }
2045
2046         /// Marks an outbound HTLC which we have received update_fail/fulfill/malformed
2047         #[inline]
2048         fn mark_outbound_htlc_removed(&mut self, htlc_id: u64, check_preimage: Option<PaymentHash>, fail_reason: Option<HTLCFailReason>) -> Result<&HTLCSource, ChannelError> {
2049                 for htlc in self.pending_outbound_htlcs.iter_mut() {
2050                         if htlc.htlc_id == htlc_id {
2051                                 match check_preimage {
2052                                         None => {},
2053                                         Some(payment_hash) =>
2054                                                 if payment_hash != htlc.payment_hash {
2055                                                         return Err(ChannelError::Close(format!("Remote tried to fulfill HTLC ({}) with an incorrect preimage", htlc_id)));
2056                                                 }
2057                                 };
2058                                 match htlc.state {
2059                                         OutboundHTLCState::LocalAnnounced(_) =>
2060                                                 return Err(ChannelError::Close(format!("Remote tried to fulfill/fail HTLC ({}) before it had been committed", htlc_id))),
2061                                         OutboundHTLCState::Committed => {
2062                                                 htlc.state = OutboundHTLCState::RemoteRemoved(fail_reason);
2063                                         },
2064                                         OutboundHTLCState::AwaitingRemoteRevokeToRemove(_) | OutboundHTLCState::AwaitingRemovedRemoteRevoke(_) | OutboundHTLCState::RemoteRemoved(_) =>
2065                                                 return Err(ChannelError::Close(format!("Remote tried to fulfill/fail HTLC ({}) that they'd already fulfilled/failed", htlc_id))),
2066                                 }
2067                                 return Ok(&htlc.source);
2068                         }
2069                 }
2070                 Err(ChannelError::Close("Remote tried to fulfill/fail an HTLC we couldn't find".to_owned()))
2071         }
2072
2073         pub fn update_fulfill_htlc(&mut self, msg: &msgs::UpdateFulfillHTLC) -> Result<HTLCSource, ChannelError> {
2074                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
2075                         return Err(ChannelError::Close("Got fulfill HTLC message when channel was not in an operational state".to_owned()));
2076                 }
2077                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2078                         return Err(ChannelError::Close("Peer sent update_fulfill_htlc when we needed a channel_reestablish".to_owned()));
2079                 }
2080
2081                 let payment_hash = PaymentHash(Sha256::hash(&msg.payment_preimage.0[..]).into_inner());
2082                 self.mark_outbound_htlc_removed(msg.htlc_id, Some(payment_hash), None).map(|source| source.clone())
2083         }
2084
2085         pub fn update_fail_htlc(&mut self, msg: &msgs::UpdateFailHTLC, fail_reason: HTLCFailReason) -> Result<(), ChannelError> {
2086                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
2087                         return Err(ChannelError::Close("Got fail HTLC message when channel was not in an operational state".to_owned()));
2088                 }
2089                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2090                         return Err(ChannelError::Close("Peer sent update_fail_htlc when we needed a channel_reestablish".to_owned()));
2091                 }
2092
2093                 self.mark_outbound_htlc_removed(msg.htlc_id, None, Some(fail_reason))?;
2094                 Ok(())
2095         }
2096
2097         pub fn update_fail_malformed_htlc(&mut self, msg: &msgs::UpdateFailMalformedHTLC, fail_reason: HTLCFailReason) -> Result<(), ChannelError> {
2098                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
2099                         return Err(ChannelError::Close("Got fail malformed HTLC message when channel was not in an operational state".to_owned()));
2100                 }
2101                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2102                         return Err(ChannelError::Close("Peer sent update_fail_malformed_htlc when we needed a channel_reestablish".to_owned()));
2103                 }
2104
2105                 self.mark_outbound_htlc_removed(msg.htlc_id, None, Some(fail_reason))?;
2106                 Ok(())
2107         }
2108
2109         pub fn commitment_signed<F: Deref, L: Deref>(&mut self, msg: &msgs::CommitmentSigned, fee_estimator: &F, logger: &L) -> Result<(msgs::RevokeAndACK, Option<msgs::CommitmentSigned>, Option<msgs::ClosingSigned>, ChannelMonitorUpdate), (Option<ChannelMonitorUpdate>, ChannelError)>
2110         where F::Target: FeeEstimator,
2111                                 L::Target: Logger
2112         {
2113                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
2114                         return Err((None, ChannelError::Close("Got commitment signed message when channel was not in an operational state".to_owned())));
2115                 }
2116                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2117                         return Err((None, ChannelError::Close("Peer sent commitment_signed when we needed a channel_reestablish".to_owned())));
2118                 }
2119                 if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK == BOTH_SIDES_SHUTDOWN_MASK && self.last_sent_closing_fee.is_some() {
2120                         return Err((None, ChannelError::Close("Peer sent commitment_signed after we'd started exchanging closing_signeds".to_owned())));
2121                 }
2122
2123                 let funding_script = self.get_funding_redeemscript();
2124
2125                 let keys = self.build_holder_transaction_keys(self.cur_holder_commitment_transaction_number).map_err(|e| (None, e))?;
2126
2127                 let mut update_fee = false;
2128                 let feerate_per_kw = if !self.is_outbound() && self.pending_update_fee.is_some() {
2129                         update_fee = true;
2130                         self.pending_update_fee.unwrap()
2131                 } else {
2132                         self.feerate_per_kw
2133                 };
2134
2135                 let (num_htlcs, mut htlcs_cloned, commitment_tx, commitment_txid) = {
2136                         let commitment_tx = self.build_commitment_transaction(self.cur_holder_commitment_transaction_number, &keys, true, false, feerate_per_kw, logger);
2137                         let commitment_txid = {
2138                                 let trusted_tx = commitment_tx.0.trust();
2139                                 let bitcoin_tx = trusted_tx.built_transaction();
2140                                 let sighash = bitcoin_tx.get_sighash_all(&funding_script, self.channel_value_satoshis);
2141
2142                                 log_trace!(logger, "Checking commitment tx signature {} by key {} against tx {} (sighash {}) with redeemscript {}", log_bytes!(msg.signature.serialize_compact()[..]), log_bytes!(self.counterparty_funding_pubkey().serialize()), encode::serialize_hex(&bitcoin_tx.transaction), log_bytes!(sighash[..]), encode::serialize_hex(&funding_script));
2143                                 if let Err(_) = self.secp_ctx.verify(&sighash, &msg.signature, &self.counterparty_funding_pubkey()) {
2144                                         return Err((None, ChannelError::Close("Invalid commitment tx signature from peer".to_owned())));
2145                                 }
2146                                 bitcoin_tx.txid
2147                         };
2148                         let htlcs_cloned: Vec<_> = commitment_tx.2.iter().map(|htlc| (htlc.0.clone(), htlc.1.map(|h| h.clone()))).collect();
2149                         (commitment_tx.1, htlcs_cloned, commitment_tx.0, commitment_txid)
2150                 };
2151
2152                 let total_fee = feerate_per_kw as u64 * (COMMITMENT_TX_BASE_WEIGHT + (num_htlcs as u64) * COMMITMENT_TX_WEIGHT_PER_HTLC) / 1000;
2153                 //If channel fee was updated by funder confirm funder can afford the new fee rate when applied to the current local commitment transaction
2154                 if update_fee {
2155                         let counterparty_reserve_we_require = Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis);
2156                         if self.channel_value_satoshis - self.value_to_self_msat / 1000 < total_fee + counterparty_reserve_we_require {
2157                                 return Err((None, ChannelError::Close("Funding remote cannot afford proposed new fee".to_owned())));
2158                         }
2159                 }
2160                 #[cfg(any(test, feature = "fuzztarget"))]
2161                 {
2162                         if self.is_outbound() {
2163                                 let projected_commit_tx_info = self.next_local_commitment_tx_fee_info_cached.lock().unwrap().take();
2164                                 *self.next_remote_commitment_tx_fee_info_cached.lock().unwrap() = None;
2165                                 if let Some(info) = projected_commit_tx_info {
2166                                         let total_pending_htlcs = self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len()
2167                                                 + self.holding_cell_htlc_updates.len();
2168                                         if info.total_pending_htlcs == total_pending_htlcs
2169                                                 && info.next_holder_htlc_id == self.next_holder_htlc_id
2170                                                 && info.next_counterparty_htlc_id == self.next_counterparty_htlc_id
2171                                                 && info.feerate == self.feerate_per_kw {
2172                                                         assert_eq!(total_fee, info.fee / 1000);
2173                                                 }
2174                                 }
2175                         }
2176                 }
2177
2178                 if msg.htlc_signatures.len() != num_htlcs {
2179                         return Err((None, ChannelError::Close(format!("Got wrong number of HTLC signatures ({}) from remote. It must be {}", msg.htlc_signatures.len(), num_htlcs))));
2180                 }
2181
2182                 // TODO: Sadly, we pass HTLCs twice to ChannelMonitor: once via the HolderCommitmentTransaction and once via the update
2183                 let mut htlcs_and_sigs = Vec::with_capacity(htlcs_cloned.len());
2184                 for (idx, (htlc, source)) in htlcs_cloned.drain(..).enumerate() {
2185                         if let Some(_) = htlc.transaction_output_index {
2186                                 let htlc_tx = self.build_htlc_transaction(&commitment_txid, &htlc, true, &keys, feerate_per_kw);
2187                                 let htlc_redeemscript = chan_utils::get_htlc_redeemscript(&htlc, &keys);
2188                                 let htlc_sighash = hash_to_message!(&bip143::SigHashCache::new(&htlc_tx).signature_hash(0, &htlc_redeemscript, htlc.amount_msat / 1000, SigHashType::All)[..]);
2189                                 log_trace!(logger, "Checking HTLC tx signature {} by key {} against tx {} (sighash {}) with redeemscript {}", log_bytes!(msg.htlc_signatures[idx].serialize_compact()[..]), log_bytes!(keys.countersignatory_htlc_key.serialize()), encode::serialize_hex(&htlc_tx), log_bytes!(htlc_sighash[..]), encode::serialize_hex(&htlc_redeemscript));
2190                                 if let Err(_) = self.secp_ctx.verify(&htlc_sighash, &msg.htlc_signatures[idx], &keys.countersignatory_htlc_key) {
2191                                         return Err((None, ChannelError::Close("Invalid HTLC tx signature from peer".to_owned())));
2192                                 }
2193                                 htlcs_and_sigs.push((htlc, Some(msg.htlc_signatures[idx]), source));
2194                         } else {
2195                                 htlcs_and_sigs.push((htlc, None, source));
2196                         }
2197                 }
2198
2199                 let holder_commitment_tx = HolderCommitmentTransaction::new(
2200                         commitment_tx,
2201                         msg.signature,
2202                         msg.htlc_signatures.clone(),
2203                         &self.get_holder_pubkeys().funding_pubkey,
2204                         self.counterparty_funding_pubkey()
2205                 );
2206
2207                 let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number - 1, &self.secp_ctx);
2208                 let per_commitment_secret = self.holder_signer.release_commitment_secret(self.cur_holder_commitment_transaction_number + 1);
2209
2210                 // Update state now that we've passed all the can-fail calls...
2211                 let mut need_commitment = false;
2212                 if !self.is_outbound() {
2213                         if let Some(fee_update) = self.pending_update_fee {
2214                                 self.feerate_per_kw = fee_update;
2215                                 // We later use the presence of pending_update_fee to indicate we should generate a
2216                                 // commitment_signed upon receipt of revoke_and_ack, so we can only set it to None
2217                                 // if we're not awaiting a revoke (ie will send a commitment_signed now).
2218                                 if (self.channel_state & ChannelState::AwaitingRemoteRevoke as u32) == 0 {
2219                                         need_commitment = true;
2220                                         self.pending_update_fee = None;
2221                                 }
2222                         }
2223                 }
2224
2225                 self.latest_monitor_update_id += 1;
2226                 let mut monitor_update = ChannelMonitorUpdate {
2227                         update_id: self.latest_monitor_update_id,
2228                         updates: vec![ChannelMonitorUpdateStep::LatestHolderCommitmentTXInfo {
2229                                 commitment_tx: holder_commitment_tx,
2230                                 htlc_outputs: htlcs_and_sigs
2231                         }]
2232                 };
2233
2234                 for htlc in self.pending_inbound_htlcs.iter_mut() {
2235                         let new_forward = if let &InboundHTLCState::RemoteAnnounced(ref forward_info) = &htlc.state {
2236                                 Some(forward_info.clone())
2237                         } else { None };
2238                         if let Some(forward_info) = new_forward {
2239                                 htlc.state = InboundHTLCState::AwaitingRemoteRevokeToAnnounce(forward_info);
2240                                 need_commitment = true;
2241                         }
2242                 }
2243                 for htlc in self.pending_outbound_htlcs.iter_mut() {
2244                         if let Some(fail_reason) = if let &mut OutboundHTLCState::RemoteRemoved(ref mut fail_reason) = &mut htlc.state {
2245                                 Some(fail_reason.take())
2246                         } else { None } {
2247                                 htlc.state = OutboundHTLCState::AwaitingRemoteRevokeToRemove(fail_reason);
2248                                 need_commitment = true;
2249                         }
2250                 }
2251
2252                 self.cur_holder_commitment_transaction_number -= 1;
2253                 // Note that if we need_commitment & !AwaitingRemoteRevoke we'll call
2254                 // send_commitment_no_status_check() next which will reset this to RAAFirst.
2255                 self.resend_order = RAACommitmentOrder::CommitmentFirst;
2256
2257                 if (self.channel_state & ChannelState::MonitorUpdateFailed as u32) != 0 {
2258                         // In case we initially failed monitor updating without requiring a response, we need
2259                         // to make sure the RAA gets sent first.
2260                         self.monitor_pending_revoke_and_ack = true;
2261                         if need_commitment && (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == 0 {
2262                                 // If we were going to send a commitment_signed after the RAA, go ahead and do all
2263                                 // the corresponding HTLC status updates so that get_last_commitment_update
2264                                 // includes the right HTLCs.
2265                                 self.monitor_pending_commitment_signed = true;
2266                                 let (_, mut additional_update) = self.send_commitment_no_status_check(logger).map_err(|e| (None, e))?;
2267                                 // send_commitment_no_status_check may bump latest_monitor_id but we want them to be
2268                                 // strictly increasing by one, so decrement it here.
2269                                 self.latest_monitor_update_id = monitor_update.update_id;
2270                                 monitor_update.updates.append(&mut additional_update.updates);
2271                         }
2272                         // TODO: Call maybe_propose_first_closing_signed on restoration (or call it here and
2273                         // re-send the message on restoration)
2274                         return Err((Some(monitor_update), ChannelError::Ignore("Previous monitor update failure prevented generation of RAA".to_owned())));
2275                 }
2276
2277                 let (commitment_signed, closing_signed) = if need_commitment && (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == 0 {
2278                         // If we're AwaitingRemoteRevoke we can't send a new commitment here, but that's ok -
2279                         // we'll send one right away when we get the revoke_and_ack when we
2280                         // free_holding_cell_htlcs().
2281                         let (msg, mut additional_update) = self.send_commitment_no_status_check(logger).map_err(|e| (None, e))?;
2282                         // send_commitment_no_status_check may bump latest_monitor_id but we want them to be
2283                         // strictly increasing by one, so decrement it here.
2284                         self.latest_monitor_update_id = monitor_update.update_id;
2285                         monitor_update.updates.append(&mut additional_update.updates);
2286                         (Some(msg), None)
2287                 } else if !need_commitment {
2288                         (None, self.maybe_propose_first_closing_signed(fee_estimator))
2289                 } else { (None, None) };
2290
2291                 Ok((msgs::RevokeAndACK {
2292                         channel_id: self.channel_id,
2293                         per_commitment_secret,
2294                         next_per_commitment_point,
2295                 }, commitment_signed, closing_signed, monitor_update))
2296         }
2297
2298         /// Used to fulfill holding_cell_htlcs when we get a remote ack (or implicitly get it by them
2299         /// fulfilling or failing the last pending HTLC)
2300         fn free_holding_cell_htlcs<L: Deref>(&mut self, logger: &L) -> Result<(Option<(msgs::CommitmentUpdate, ChannelMonitorUpdate)>, Vec<(HTLCSource, PaymentHash)>), ChannelError> where L::Target: Logger {
2301                 assert_eq!(self.channel_state & ChannelState::MonitorUpdateFailed as u32, 0);
2302                 if self.holding_cell_htlc_updates.len() != 0 || self.holding_cell_update_fee.is_some() {
2303                         log_trace!(logger, "Freeing holding cell with {} HTLC updates{}", self.holding_cell_htlc_updates.len(), if self.holding_cell_update_fee.is_some() { " and a fee update" } else { "" });
2304
2305                         let mut monitor_update = ChannelMonitorUpdate {
2306                                 update_id: self.latest_monitor_update_id + 1, // We don't increment this yet!
2307                                 updates: Vec::new(),
2308                         };
2309
2310                         let mut htlc_updates = Vec::new();
2311                         mem::swap(&mut htlc_updates, &mut self.holding_cell_htlc_updates);
2312                         let mut update_add_htlcs = Vec::with_capacity(htlc_updates.len());
2313                         let mut update_fulfill_htlcs = Vec::with_capacity(htlc_updates.len());
2314                         let mut update_fail_htlcs = Vec::with_capacity(htlc_updates.len());
2315                         let mut htlcs_to_fail = Vec::new();
2316                         for htlc_update in htlc_updates.drain(..) {
2317                                 // Note that this *can* fail, though it should be due to rather-rare conditions on
2318                                 // fee races with adding too many outputs which push our total payments just over
2319                                 // the limit. In case it's less rare than I anticipate, we may want to revisit
2320                                 // handling this case better and maybe fulfilling some of the HTLCs while attempting
2321                                 // to rebalance channels.
2322                                 match &htlc_update {
2323                                         &HTLCUpdateAwaitingACK::AddHTLC {amount_msat, cltv_expiry, ref payment_hash, ref source, ref onion_routing_packet, ..} => {
2324                                                 match self.send_htlc(amount_msat, *payment_hash, cltv_expiry, source.clone(), onion_routing_packet.clone()) {
2325                                                         Ok(update_add_msg_option) => update_add_htlcs.push(update_add_msg_option.unwrap()),
2326                                                         Err(e) => {
2327                                                                 match e {
2328                                                                         ChannelError::Ignore(ref msg) => {
2329                                                                                 log_info!(logger, "Failed to send HTLC with payment_hash {} due to {}", log_bytes!(payment_hash.0), msg);
2330                                                                                 // If we fail to send here, then this HTLC should
2331                                                                                 // be failed backwards. Failing to send here
2332                                                                                 // indicates that this HTLC may keep being put back
2333                                                                                 // into the holding cell without ever being
2334                                                                                 // successfully forwarded/failed/fulfilled, causing
2335                                                                                 // our counterparty to eventually close on us.
2336                                                                                 htlcs_to_fail.push((source.clone(), *payment_hash));
2337                                                                         },
2338                                                                         _ => {
2339                                                                                 panic!("Got a non-IgnoreError action trying to send holding cell HTLC");
2340                                                                         },
2341                                                                 }
2342                                                         }
2343                                                 }
2344                                         },
2345                                         &HTLCUpdateAwaitingACK::ClaimHTLC { ref payment_preimage, htlc_id, .. } => {
2346                                                 match self.get_update_fulfill_htlc(htlc_id, *payment_preimage, logger) {
2347                                                         Ok((update_fulfill_msg_option, additional_monitor_update_opt)) => {
2348                                                                 update_fulfill_htlcs.push(update_fulfill_msg_option.unwrap());
2349                                                                 if let Some(mut additional_monitor_update) = additional_monitor_update_opt {
2350                                                                         monitor_update.updates.append(&mut additional_monitor_update.updates);
2351                                                                 }
2352                                                         },
2353                                                         Err(e) => {
2354                                                                 if let ChannelError::Ignore(_) = e {}
2355                                                                 else {
2356                                                                         panic!("Got a non-IgnoreError action trying to fulfill holding cell HTLC");
2357                                                                 }
2358                                                         }
2359                                                 }
2360                                         },
2361                                         &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, ref err_packet } => {
2362                                                 match self.get_update_fail_htlc(htlc_id, err_packet.clone()) {
2363                                                         Ok(update_fail_msg_option) => update_fail_htlcs.push(update_fail_msg_option.unwrap()),
2364                                                         Err(e) => {
2365                                                                 if let ChannelError::Ignore(_) = e {}
2366                                                                 else {
2367                                                                         panic!("Got a non-IgnoreError action trying to fail holding cell HTLC");
2368                                                                 }
2369                                                         }
2370                                                 }
2371                                         },
2372                                 }
2373                         }
2374                         if update_add_htlcs.is_empty() && update_fulfill_htlcs.is_empty() && update_fail_htlcs.is_empty() && self.holding_cell_update_fee.is_none() {
2375                                 return Ok((None, htlcs_to_fail));
2376                         }
2377                         let update_fee = if let Some(feerate) = self.holding_cell_update_fee {
2378                                 self.pending_update_fee = self.holding_cell_update_fee.take();
2379                                 Some(msgs::UpdateFee {
2380                                         channel_id: self.channel_id,
2381                                         feerate_per_kw: feerate as u32,
2382                                 })
2383                         } else {
2384                                 None
2385                         };
2386
2387                         let (commitment_signed, mut additional_update) = self.send_commitment_no_status_check(logger)?;
2388                         // send_commitment_no_status_check and get_update_fulfill_htlc may bump latest_monitor_id
2389                         // but we want them to be strictly increasing by one, so reset it here.
2390                         self.latest_monitor_update_id = monitor_update.update_id;
2391                         monitor_update.updates.append(&mut additional_update.updates);
2392
2393                         Ok((Some((msgs::CommitmentUpdate {
2394                                 update_add_htlcs,
2395                                 update_fulfill_htlcs,
2396                                 update_fail_htlcs,
2397                                 update_fail_malformed_htlcs: Vec::new(),
2398                                 update_fee,
2399                                 commitment_signed,
2400                         }, monitor_update)), htlcs_to_fail))
2401                 } else {
2402                         Ok((None, Vec::new()))
2403                 }
2404         }
2405
2406         /// Handles receiving a remote's revoke_and_ack. Note that we may return a new
2407         /// commitment_signed message here in case we had pending outbound HTLCs to add which were
2408         /// waiting on this revoke_and_ack. The generation of this new commitment_signed may also fail,
2409         /// generating an appropriate error *after* the channel state has been updated based on the
2410         /// revoke_and_ack message.
2411         pub fn revoke_and_ack<F: Deref, L: Deref>(&mut self, msg: &msgs::RevokeAndACK, fee_estimator: &F, logger: &L) -> Result<(Option<msgs::CommitmentUpdate>, Vec<(PendingHTLCInfo, u64)>, Vec<(HTLCSource, PaymentHash, HTLCFailReason)>, Option<msgs::ClosingSigned>, ChannelMonitorUpdate, Vec<(HTLCSource, PaymentHash)>), ChannelError>
2412                 where F::Target: FeeEstimator,
2413                                         L::Target: Logger,
2414         {
2415                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
2416                         return Err(ChannelError::Close("Got revoke/ACK message when channel was not in an operational state".to_owned()));
2417                 }
2418                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2419                         return Err(ChannelError::Close("Peer sent revoke_and_ack when we needed a channel_reestablish".to_owned()));
2420                 }
2421                 if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK == BOTH_SIDES_SHUTDOWN_MASK && self.last_sent_closing_fee.is_some() {
2422                         return Err(ChannelError::Close("Peer sent revoke_and_ack after we'd started exchanging closing_signeds".to_owned()));
2423                 }
2424
2425                 if let Some(counterparty_prev_commitment_point) = self.counterparty_prev_commitment_point {
2426                         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 {
2427                                 return Err(ChannelError::Close("Got a revoke commitment secret which didn't correspond to their current pubkey".to_owned()));
2428                         }
2429                 }
2430
2431                 if self.channel_state & ChannelState::AwaitingRemoteRevoke as u32 == 0 {
2432                         // Our counterparty seems to have burned their coins to us (by revoking a state when we
2433                         // haven't given them a new commitment transaction to broadcast). We should probably
2434                         // take advantage of this by updating our channel monitor, sending them an error, and
2435                         // waiting for them to broadcast their latest (now-revoked claim). But, that would be a
2436                         // lot of work, and there's some chance this is all a misunderstanding anyway.
2437                         // We have to do *something*, though, since our signer may get mad at us for otherwise
2438                         // jumping a remote commitment number, so best to just force-close and move on.
2439                         return Err(ChannelError::Close("Received an unexpected revoke_and_ack".to_owned()));
2440                 }
2441
2442                 #[cfg(any(test, feature = "fuzztarget"))]
2443                 {
2444                         *self.next_local_commitment_tx_fee_info_cached.lock().unwrap() = None;
2445                         *self.next_remote_commitment_tx_fee_info_cached.lock().unwrap() = None;
2446                 }
2447
2448                 self.commitment_secrets.provide_secret(self.cur_counterparty_commitment_transaction_number + 1, msg.per_commitment_secret)
2449                         .map_err(|_| ChannelError::Close("Previous secrets did not match new one".to_owned()))?;
2450                 self.latest_monitor_update_id += 1;
2451                 let mut monitor_update = ChannelMonitorUpdate {
2452                         update_id: self.latest_monitor_update_id,
2453                         updates: vec![ChannelMonitorUpdateStep::CommitmentSecret {
2454                                 idx: self.cur_counterparty_commitment_transaction_number + 1,
2455                                 secret: msg.per_commitment_secret,
2456                         }],
2457                 };
2458
2459                 // Update state now that we've passed all the can-fail calls...
2460                 // (note that we may still fail to generate the new commitment_signed message, but that's
2461                 // OK, we step the channel here and *then* if the new generation fails we can fail the
2462                 // channel based on that, but stepping stuff here should be safe either way.
2463                 self.channel_state &= !(ChannelState::AwaitingRemoteRevoke as u32);
2464                 self.counterparty_prev_commitment_point = self.counterparty_cur_commitment_point;
2465                 self.counterparty_cur_commitment_point = Some(msg.next_per_commitment_point);
2466                 self.cur_counterparty_commitment_transaction_number -= 1;
2467
2468                 log_trace!(logger, "Updating HTLCs on receipt of RAA...");
2469                 let mut to_forward_infos = Vec::new();
2470                 let mut revoked_htlcs = Vec::new();
2471                 let mut update_fail_htlcs = Vec::new();
2472                 let mut update_fail_malformed_htlcs = Vec::new();
2473                 let mut require_commitment = false;
2474                 let mut value_to_self_msat_diff: i64 = 0;
2475
2476                 {
2477                         // Take references explicitly so that we can hold multiple references to self.
2478                         let pending_inbound_htlcs: &mut Vec<_> = &mut self.pending_inbound_htlcs;
2479                         let pending_outbound_htlcs: &mut Vec<_> = &mut self.pending_outbound_htlcs;
2480
2481                         // We really shouldnt have two passes here, but retain gives a non-mutable ref (Rust bug)
2482                         pending_inbound_htlcs.retain(|htlc| {
2483                                 if let &InboundHTLCState::LocalRemoved(ref reason) = &htlc.state {
2484                                         log_trace!(logger, " ...removing inbound LocalRemoved {}", log_bytes!(htlc.payment_hash.0));
2485                                         if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
2486                                                 value_to_self_msat_diff += htlc.amount_msat as i64;
2487                                         }
2488                                         false
2489                                 } else { true }
2490                         });
2491                         pending_outbound_htlcs.retain(|htlc| {
2492                                 if let &OutboundHTLCState::AwaitingRemovedRemoteRevoke(ref fail_reason) = &htlc.state {
2493                                         log_trace!(logger, " ...removing outbound AwaitingRemovedRemoteRevoke {}", log_bytes!(htlc.payment_hash.0));
2494                                         if let Some(reason) = fail_reason.clone() { // We really want take() here, but, again, non-mut ref :(
2495                                                 revoked_htlcs.push((htlc.source.clone(), htlc.payment_hash, reason));
2496                                         } else {
2497                                                 // They fulfilled, so we sent them money
2498                                                 value_to_self_msat_diff -= htlc.amount_msat as i64;
2499                                         }
2500                                         false
2501                                 } else { true }
2502                         });
2503                         for htlc in pending_inbound_htlcs.iter_mut() {
2504                                 let swap = if let &InboundHTLCState::AwaitingRemoteRevokeToAnnounce(_) = &htlc.state {
2505                                         log_trace!(logger, " ...promoting inbound AwaitingRemoteRevokeToAnnounce {} to Committed", log_bytes!(htlc.payment_hash.0));
2506                                         true
2507                                 } else if let &InboundHTLCState::AwaitingAnnouncedRemoteRevoke(_) = &htlc.state {
2508                                         log_trace!(logger, " ...promoting inbound AwaitingAnnouncedRemoteRevoke {} to Committed", log_bytes!(htlc.payment_hash.0));
2509                                         true
2510                                 } else { false };
2511                                 if swap {
2512                                         let mut state = InboundHTLCState::Committed;
2513                                         mem::swap(&mut state, &mut htlc.state);
2514
2515                                         if let InboundHTLCState::AwaitingRemoteRevokeToAnnounce(forward_info) = state {
2516                                                 htlc.state = InboundHTLCState::AwaitingAnnouncedRemoteRevoke(forward_info);
2517                                                 require_commitment = true;
2518                                         } else if let InboundHTLCState::AwaitingAnnouncedRemoteRevoke(forward_info) = state {
2519                                                 match forward_info {
2520                                                         PendingHTLCStatus::Fail(fail_msg) => {
2521                                                                 require_commitment = true;
2522                                                                 match fail_msg {
2523                                                                         HTLCFailureMsg::Relay(msg) => {
2524                                                                                 htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::FailRelay(msg.reason.clone()));
2525                                                                                 update_fail_htlcs.push(msg)
2526                                                                         },
2527                                                                         HTLCFailureMsg::Malformed(msg) => {
2528                                                                                 htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::FailMalformed((msg.sha256_of_onion, msg.failure_code)));
2529                                                                                 update_fail_malformed_htlcs.push(msg)
2530                                                                         },
2531                                                                 }
2532                                                         },
2533                                                         PendingHTLCStatus::Forward(forward_info) => {
2534                                                                 to_forward_infos.push((forward_info, htlc.htlc_id));
2535                                                                 htlc.state = InboundHTLCState::Committed;
2536                                                         }
2537                                                 }
2538                                         }
2539                                 }
2540                         }
2541                         for htlc in pending_outbound_htlcs.iter_mut() {
2542                                 if let OutboundHTLCState::LocalAnnounced(_) = htlc.state {
2543                                         log_trace!(logger, " ...promoting outbound LocalAnnounced {} to Committed", log_bytes!(htlc.payment_hash.0));
2544                                         htlc.state = OutboundHTLCState::Committed;
2545                                 }
2546                                 if let Some(fail_reason) = if let &mut OutboundHTLCState::AwaitingRemoteRevokeToRemove(ref mut fail_reason) = &mut htlc.state {
2547                                         Some(fail_reason.take())
2548                                 } else { None } {
2549                                         log_trace!(logger, " ...promoting outbound AwaitingRemoteRevokeToRemove {} to AwaitingRemovedRemoteRevoke", log_bytes!(htlc.payment_hash.0));
2550                                         htlc.state = OutboundHTLCState::AwaitingRemovedRemoteRevoke(fail_reason);
2551                                         require_commitment = true;
2552                                 }
2553                         }
2554                 }
2555                 self.value_to_self_msat = (self.value_to_self_msat as i64 + value_to_self_msat_diff) as u64;
2556
2557                 if self.is_outbound() {
2558                         if let Some(feerate) = self.pending_update_fee.take() {
2559                                 self.feerate_per_kw = feerate;
2560                         }
2561                 } else {
2562                         if let Some(feerate) = self.pending_update_fee {
2563                                 // Because a node cannot send two commitment_signeds in a row without getting a
2564                                 // revoke_and_ack from us (as it would otherwise not know the per_commitment_point
2565                                 // it should use to create keys with) and because a node can't send a
2566                                 // commitment_signed without changes, checking if the feerate is equal to the
2567                                 // pending feerate update is sufficient to detect require_commitment.
2568                                 if feerate == self.feerate_per_kw {
2569                                         require_commitment = true;
2570                                         self.pending_update_fee = None;
2571                                 }
2572                         }
2573                 }
2574
2575                 if (self.channel_state & ChannelState::MonitorUpdateFailed as u32) == ChannelState::MonitorUpdateFailed as u32 {
2576                         // We can't actually generate a new commitment transaction (incl by freeing holding
2577                         // cells) while we can't update the monitor, so we just return what we have.
2578                         if require_commitment {
2579                                 self.monitor_pending_commitment_signed = true;
2580                                 // When the monitor updating is restored we'll call get_last_commitment_update(),
2581                                 // which does not update state, but we're definitely now awaiting a remote revoke
2582                                 // before we can step forward any more, so set it here.
2583                                 let (_, mut additional_update) = self.send_commitment_no_status_check(logger)?;
2584                                 // send_commitment_no_status_check may bump latest_monitor_id but we want them to be
2585                                 // strictly increasing by one, so decrement it here.
2586                                 self.latest_monitor_update_id = monitor_update.update_id;
2587                                 monitor_update.updates.append(&mut additional_update.updates);
2588                         }
2589                         self.monitor_pending_forwards.append(&mut to_forward_infos);
2590                         self.monitor_pending_failures.append(&mut revoked_htlcs);
2591                         return Ok((None, Vec::new(), Vec::new(), None, monitor_update, Vec::new()))
2592                 }
2593
2594                 match self.free_holding_cell_htlcs(logger)? {
2595                         (Some((mut commitment_update, mut additional_update)), htlcs_to_fail) => {
2596                                 commitment_update.update_fail_htlcs.reserve(update_fail_htlcs.len());
2597                                 for fail_msg in update_fail_htlcs.drain(..) {
2598                                         commitment_update.update_fail_htlcs.push(fail_msg);
2599                                 }
2600                                 commitment_update.update_fail_malformed_htlcs.reserve(update_fail_malformed_htlcs.len());
2601                                 for fail_msg in update_fail_malformed_htlcs.drain(..) {
2602                                         commitment_update.update_fail_malformed_htlcs.push(fail_msg);
2603                                 }
2604
2605                                 // free_holding_cell_htlcs may bump latest_monitor_id multiple times but we want them to be
2606                                 // strictly increasing by one, so decrement it here.
2607                                 self.latest_monitor_update_id = monitor_update.update_id;
2608                                 monitor_update.updates.append(&mut additional_update.updates);
2609
2610                                 Ok((Some(commitment_update), to_forward_infos, revoked_htlcs, None, monitor_update, htlcs_to_fail))
2611                         },
2612                         (None, htlcs_to_fail) => {
2613                                 if require_commitment {
2614                                         let (commitment_signed, mut additional_update) = self.send_commitment_no_status_check(logger)?;
2615
2616                                         // send_commitment_no_status_check may bump latest_monitor_id but we want them to be
2617                                         // strictly increasing by one, so decrement it here.
2618                                         self.latest_monitor_update_id = monitor_update.update_id;
2619                                         monitor_update.updates.append(&mut additional_update.updates);
2620
2621                                         Ok((Some(msgs::CommitmentUpdate {
2622                                                 update_add_htlcs: Vec::new(),
2623                                                 update_fulfill_htlcs: Vec::new(),
2624                                                 update_fail_htlcs,
2625                                                 update_fail_malformed_htlcs,
2626                                                 update_fee: None,
2627                                                 commitment_signed
2628                                         }), to_forward_infos, revoked_htlcs, None, monitor_update, htlcs_to_fail))
2629                                 } else {
2630                                         Ok((None, to_forward_infos, revoked_htlcs, self.maybe_propose_first_closing_signed(fee_estimator), monitor_update, htlcs_to_fail))
2631                                 }
2632                         }
2633                 }
2634
2635         }
2636
2637         /// Adds a pending update to this channel. See the doc for send_htlc for
2638         /// further details on the optionness of the return value.
2639         /// You MUST call send_commitment prior to any other calls on this Channel
2640         fn send_update_fee(&mut self, feerate_per_kw: u32) -> Option<msgs::UpdateFee> {
2641                 if !self.is_outbound() {
2642                         panic!("Cannot send fee from inbound channel");
2643                 }
2644                 if !self.is_usable() {
2645                         panic!("Cannot update fee until channel is fully established and we haven't started shutting down");
2646                 }
2647                 if !self.is_live() {
2648                         panic!("Cannot update fee while peer is disconnected/we're awaiting a monitor update (ChannelManager should have caught this)");
2649                 }
2650
2651                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == (ChannelState::AwaitingRemoteRevoke as u32) {
2652                         self.holding_cell_update_fee = Some(feerate_per_kw);
2653                         return None;
2654                 }
2655
2656                 debug_assert!(self.pending_update_fee.is_none());
2657                 self.pending_update_fee = Some(feerate_per_kw);
2658
2659                 Some(msgs::UpdateFee {
2660                         channel_id: self.channel_id,
2661                         feerate_per_kw,
2662                 })
2663         }
2664
2665         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 {
2666                 match self.send_update_fee(feerate_per_kw) {
2667                         Some(update_fee) => {
2668                                 let (commitment_signed, monitor_update) = self.send_commitment_no_status_check(logger)?;
2669                                 Ok(Some((update_fee, commitment_signed, monitor_update)))
2670                         },
2671                         None => Ok(None)
2672                 }
2673         }
2674
2675         /// Removes any uncommitted HTLCs, to be used on peer disconnection, including any pending
2676         /// HTLCs that we intended to add but haven't as we were waiting on a remote revoke.
2677         /// Returns the set of PendingHTLCStatuses from remote uncommitted HTLCs (which we're
2678         /// implicitly dropping) and the payment_hashes of HTLCs we tried to add but are dropping.
2679         /// No further message handling calls may be made until a channel_reestablish dance has
2680         /// completed.
2681         pub fn remove_uncommitted_htlcs_and_mark_paused<L: Deref>(&mut self, logger: &L) -> Vec<(HTLCSource, PaymentHash)> where L::Target: Logger {
2682                 let mut outbound_drops = Vec::new();
2683
2684                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
2685                 if self.channel_state < ChannelState::FundingSent as u32 {
2686                         self.channel_state = ChannelState::ShutdownComplete as u32;
2687                         return outbound_drops;
2688                 }
2689                 // Upon reconnect we have to start the closing_signed dance over, but shutdown messages
2690                 // will be retransmitted.
2691                 self.last_sent_closing_fee = None;
2692
2693                 let mut inbound_drop_count = 0;
2694                 self.pending_inbound_htlcs.retain(|htlc| {
2695                         match htlc.state {
2696                                 InboundHTLCState::RemoteAnnounced(_) => {
2697                                         // They sent us an update_add_htlc but we never got the commitment_signed.
2698                                         // We'll tell them what commitment_signed we're expecting next and they'll drop
2699                                         // this HTLC accordingly
2700                                         inbound_drop_count += 1;
2701                                         false
2702                                 },
2703                                 InboundHTLCState::AwaitingRemoteRevokeToAnnounce(_)|InboundHTLCState::AwaitingAnnouncedRemoteRevoke(_) => {
2704                                         // We received a commitment_signed updating this HTLC and (at least hopefully)
2705                                         // sent a revoke_and_ack (which we can re-transmit) and have heard nothing
2706                                         // in response to it yet, so don't touch it.
2707                                         true
2708                                 },
2709                                 InboundHTLCState::Committed => true,
2710                                 InboundHTLCState::LocalRemoved(_) => {
2711                                         // We (hopefully) sent a commitment_signed updating this HTLC (which we can
2712                                         // re-transmit if needed) and they may have even sent a revoke_and_ack back
2713                                         // (that we missed). Keep this around for now and if they tell us they missed
2714                                         // the commitment_signed we can re-transmit the update then.
2715                                         true
2716                                 },
2717                         }
2718                 });
2719                 self.next_counterparty_htlc_id -= inbound_drop_count;
2720
2721                 for htlc in self.pending_outbound_htlcs.iter_mut() {
2722                         if let OutboundHTLCState::RemoteRemoved(_) = htlc.state {
2723                                 // They sent us an update to remove this but haven't yet sent the corresponding
2724                                 // commitment_signed, we need to move it back to Committed and they can re-send
2725                                 // the update upon reconnection.
2726                                 htlc.state = OutboundHTLCState::Committed;
2727                         }
2728                 }
2729
2730                 self.holding_cell_htlc_updates.retain(|htlc_update| {
2731                         match htlc_update {
2732                                 // Note that currently on channel reestablish we assert that there are
2733                                 // no holding cell HTLC update_adds, so if in the future we stop
2734                                 // dropping added HTLCs here and failing them backwards, then there will
2735                                 // need to be corresponding changes made in the Channel's re-establish
2736                                 // logic.
2737                                 &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, ref source, .. } => {
2738                                         outbound_drops.push((source.clone(), payment_hash.clone()));
2739                                         false
2740                                 },
2741                                 &HTLCUpdateAwaitingACK::ClaimHTLC {..} | &HTLCUpdateAwaitingACK::FailHTLC {..} => true,
2742                         }
2743                 });
2744                 self.channel_state |= ChannelState::PeerDisconnected as u32;
2745                 log_debug!(logger, "Peer disconnection resulted in {} remote-announced HTLC drops and {} waiting-to-locally-announced HTLC drops on channel {}", outbound_drops.len(), inbound_drop_count, log_bytes!(self.channel_id()));
2746                 outbound_drops
2747         }
2748
2749         /// Indicates that a ChannelMonitor update failed to be stored by the client and further
2750         /// updates are partially paused.
2751         /// This must be called immediately after the call which generated the ChannelMonitor update
2752         /// which failed. The messages which were generated from that call which generated the
2753         /// monitor update failure must *not* have been sent to the remote end, and must instead
2754         /// have been dropped. They will be regenerated when monitor_updating_restored is called.
2755         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)>) {
2756                 assert_eq!(self.channel_state & ChannelState::MonitorUpdateFailed as u32, 0);
2757                 self.monitor_pending_revoke_and_ack = resend_raa;
2758                 self.monitor_pending_commitment_signed = resend_commitment;
2759                 assert!(self.monitor_pending_forwards.is_empty());
2760                 mem::swap(&mut pending_forwards, &mut self.monitor_pending_forwards);
2761                 assert!(self.monitor_pending_failures.is_empty());
2762                 mem::swap(&mut pending_fails, &mut self.monitor_pending_failures);
2763                 self.channel_state |= ChannelState::MonitorUpdateFailed as u32;
2764         }
2765
2766         /// Indicates that the latest ChannelMonitor update has been committed by the client
2767         /// successfully and we should restore normal operation. Returns messages which should be sent
2768         /// to the remote side.
2769         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 {
2770                 assert_eq!(self.channel_state & ChannelState::MonitorUpdateFailed as u32, ChannelState::MonitorUpdateFailed as u32);
2771                 self.channel_state &= !(ChannelState::MonitorUpdateFailed as u32);
2772
2773                 let funding_broadcastable = if self.channel_state & (ChannelState::FundingSent as u32) != 0 && self.is_outbound() {
2774                         self.funding_transaction.take()
2775                 } else { None };
2776
2777                 // We will never broadcast the funding transaction when we're in MonitorUpdateFailed (and
2778                 // we assume the user never directly broadcasts the funding transaction and waits for us to
2779                 // do it). Thus, we can only ever hit monitor_pending_funding_locked when we're an inbound
2780                 // channel which failed to persist the monitor on funding_created, and we got the funding
2781                 // transaction confirmed before the monitor was persisted.
2782                 let funding_locked = if self.monitor_pending_funding_locked {
2783                         assert!(!self.is_outbound(), "Funding transaction broadcast by the local client before it should have - LDK didn't do it!");
2784                         self.monitor_pending_funding_locked = false;
2785                         let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
2786                         Some(msgs::FundingLocked {
2787                                 channel_id: self.channel_id(),
2788                                 next_per_commitment_point,
2789                         })
2790                 } else { None };
2791
2792                 let mut forwards = Vec::new();
2793                 mem::swap(&mut forwards, &mut self.monitor_pending_forwards);
2794                 let mut failures = Vec::new();
2795                 mem::swap(&mut failures, &mut self.monitor_pending_failures);
2796
2797                 if self.channel_state & (ChannelState::PeerDisconnected as u32) != 0 {
2798                         self.monitor_pending_revoke_and_ack = false;
2799                         self.monitor_pending_commitment_signed = false;
2800                         return (None, None, RAACommitmentOrder::RevokeAndACKFirst, forwards, failures, funding_broadcastable, funding_locked);
2801                 }
2802
2803                 let raa = if self.monitor_pending_revoke_and_ack {
2804                         Some(self.get_last_revoke_and_ack())
2805                 } else { None };
2806                 let commitment_update = if self.monitor_pending_commitment_signed {
2807                         Some(self.get_last_commitment_update(logger))
2808                 } else { None };
2809
2810                 self.monitor_pending_revoke_and_ack = false;
2811                 self.monitor_pending_commitment_signed = false;
2812                 let order = self.resend_order.clone();
2813                 log_trace!(logger, "Restored monitor updating resulting in {}{} commitment update and {} RAA, with {} first",
2814                         if funding_broadcastable.is_some() { "a funding broadcastable, " } else { "" },
2815                         if commitment_update.is_some() { "a" } else { "no" },
2816                         if raa.is_some() { "an" } else { "no" },
2817                         match order { RAACommitmentOrder::CommitmentFirst => "commitment", RAACommitmentOrder::RevokeAndACKFirst => "RAA"});
2818                 (raa, commitment_update, order, forwards, failures, funding_broadcastable, funding_locked)
2819         }
2820
2821         pub fn update_fee<F: Deref>(&mut self, fee_estimator: &F, msg: &msgs::UpdateFee) -> Result<(), ChannelError>
2822                 where F::Target: FeeEstimator
2823         {
2824                 if self.is_outbound() {
2825                         return Err(ChannelError::Close("Non-funding remote tried to update channel fee".to_owned()));
2826                 }
2827                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2828                         return Err(ChannelError::Close("Peer sent update_fee when we needed a channel_reestablish".to_owned()));
2829                 }
2830                 Channel::<Signer>::check_remote_fee(fee_estimator, msg.feerate_per_kw)?;
2831                 self.pending_update_fee = Some(msg.feerate_per_kw);
2832                 self.update_time_counter += 1;
2833                 Ok(())
2834         }
2835
2836         fn get_last_revoke_and_ack(&self) -> msgs::RevokeAndACK {
2837                 let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
2838                 let per_commitment_secret = self.holder_signer.release_commitment_secret(self.cur_holder_commitment_transaction_number + 2);
2839                 msgs::RevokeAndACK {
2840                         channel_id: self.channel_id,
2841                         per_commitment_secret,
2842                         next_per_commitment_point,
2843                 }
2844         }
2845
2846         fn get_last_commitment_update<L: Deref>(&self, logger: &L) -> msgs::CommitmentUpdate where L::Target: Logger {
2847                 let mut update_add_htlcs = Vec::new();
2848                 let mut update_fulfill_htlcs = Vec::new();
2849                 let mut update_fail_htlcs = Vec::new();
2850                 let mut update_fail_malformed_htlcs = Vec::new();
2851
2852                 for htlc in self.pending_outbound_htlcs.iter() {
2853                         if let &OutboundHTLCState::LocalAnnounced(ref onion_packet) = &htlc.state {
2854                                 update_add_htlcs.push(msgs::UpdateAddHTLC {
2855                                         channel_id: self.channel_id(),
2856                                         htlc_id: htlc.htlc_id,
2857                                         amount_msat: htlc.amount_msat,
2858                                         payment_hash: htlc.payment_hash,
2859                                         cltv_expiry: htlc.cltv_expiry,
2860                                         onion_routing_packet: (**onion_packet).clone(),
2861                                 });
2862                         }
2863                 }
2864
2865                 for htlc in self.pending_inbound_htlcs.iter() {
2866                         if let &InboundHTLCState::LocalRemoved(ref reason) = &htlc.state {
2867                                 match reason {
2868                                         &InboundHTLCRemovalReason::FailRelay(ref err_packet) => {
2869                                                 update_fail_htlcs.push(msgs::UpdateFailHTLC {
2870                                                         channel_id: self.channel_id(),
2871                                                         htlc_id: htlc.htlc_id,
2872                                                         reason: err_packet.clone()
2873                                                 });
2874                                         },
2875                                         &InboundHTLCRemovalReason::FailMalformed((ref sha256_of_onion, ref failure_code)) => {
2876                                                 update_fail_malformed_htlcs.push(msgs::UpdateFailMalformedHTLC {
2877                                                         channel_id: self.channel_id(),
2878                                                         htlc_id: htlc.htlc_id,
2879                                                         sha256_of_onion: sha256_of_onion.clone(),
2880                                                         failure_code: failure_code.clone(),
2881                                                 });
2882                                         },
2883                                         &InboundHTLCRemovalReason::Fulfill(ref payment_preimage) => {
2884                                                 update_fulfill_htlcs.push(msgs::UpdateFulfillHTLC {
2885                                                         channel_id: self.channel_id(),
2886                                                         htlc_id: htlc.htlc_id,
2887                                                         payment_preimage: payment_preimage.clone(),
2888                                                 });
2889                                         },
2890                                 }
2891                         }
2892                 }
2893
2894                 log_trace!(logger, "Regenerated latest commitment update with {} update_adds, {} update_fulfills, {} update_fails, and {} update_fail_malformeds",
2895                                 update_add_htlcs.len(), update_fulfill_htlcs.len(), update_fail_htlcs.len(), update_fail_malformed_htlcs.len());
2896                 msgs::CommitmentUpdate {
2897                         update_add_htlcs, update_fulfill_htlcs, update_fail_htlcs, update_fail_malformed_htlcs,
2898                         update_fee: None,
2899                         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,
2900                 }
2901         }
2902
2903         /// May panic if some calls other than message-handling calls (which will all Err immediately)
2904         /// have been called between remove_uncommitted_htlcs_and_mark_paused and this call.
2905         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, Option<msgs::Shutdown>), ChannelError> where L::Target: Logger {
2906                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == 0 {
2907                         // While BOLT 2 doesn't indicate explicitly we should error this channel here, it
2908                         // almost certainly indicates we are going to end up out-of-sync in some way, so we
2909                         // just close here instead of trying to recover.
2910                         return Err(ChannelError::Close("Peer sent a loose channel_reestablish not after reconnect".to_owned()));
2911                 }
2912
2913                 if msg.next_local_commitment_number >= INITIAL_COMMITMENT_NUMBER || msg.next_remote_commitment_number >= INITIAL_COMMITMENT_NUMBER ||
2914                         msg.next_local_commitment_number == 0 {
2915                         return Err(ChannelError::Close("Peer sent a garbage channel_reestablish".to_owned()));
2916                 }
2917
2918                 if msg.next_remote_commitment_number > 0 {
2919                         match msg.data_loss_protect {
2920                                 OptionalField::Present(ref data_loss) => {
2921                                         let expected_point = self.holder_signer.get_per_commitment_point(INITIAL_COMMITMENT_NUMBER - msg.next_remote_commitment_number + 1, &self.secp_ctx);
2922                                         let given_secret = SecretKey::from_slice(&data_loss.your_last_per_commitment_secret)
2923                                                 .map_err(|_| ChannelError::Close("Peer sent a garbage channel_reestablish with unparseable secret key".to_owned()))?;
2924                                         if expected_point != PublicKey::from_secret_key(&self.secp_ctx, &given_secret) {
2925                                                 return Err(ChannelError::Close("Peer sent a garbage channel_reestablish with secret key not matching the commitment height provided".to_owned()));
2926                                         }
2927                                         if msg.next_remote_commitment_number > INITIAL_COMMITMENT_NUMBER - self.cur_holder_commitment_transaction_number {
2928                                                 return Err(ChannelError::CloseDelayBroadcast(
2929                                                         "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()
2930                                                 ));
2931                                         }
2932                                 },
2933                                 OptionalField::Absent => {}
2934                         }
2935                 }
2936
2937                 // Go ahead and unmark PeerDisconnected as various calls we may make check for it (and all
2938                 // remaining cases either succeed or ErrorMessage-fail).
2939                 self.channel_state &= !(ChannelState::PeerDisconnected as u32);
2940
2941                 let shutdown_msg = if self.channel_state & (ChannelState::LocalShutdownSent as u32) != 0 {
2942                         Some(msgs::Shutdown {
2943                                 channel_id: self.channel_id,
2944                                 scriptpubkey: self.get_closing_scriptpubkey(),
2945                         })
2946                 } else { None };
2947
2948                 if self.channel_state & (ChannelState::FundingSent as u32) == ChannelState::FundingSent as u32 {
2949                         // If we're waiting on a monitor update, we shouldn't re-send any funding_locked's.
2950                         if self.channel_state & (ChannelState::OurFundingLocked as u32) == 0 ||
2951                                         self.channel_state & (ChannelState::MonitorUpdateFailed as u32) != 0 {
2952                                 if msg.next_remote_commitment_number != 0 {
2953                                         return Err(ChannelError::Close("Peer claimed they saw a revoke_and_ack but we haven't sent funding_locked yet".to_owned()));
2954                                 }
2955                                 // Short circuit the whole handler as there is nothing we can resend them
2956                                 return Ok((None, None, None, None, RAACommitmentOrder::CommitmentFirst, shutdown_msg));
2957                         }
2958
2959                         // We have OurFundingLocked set!
2960                         let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
2961                         return Ok((Some(msgs::FundingLocked {
2962                                 channel_id: self.channel_id(),
2963                                 next_per_commitment_point,
2964                         }), None, None, None, RAACommitmentOrder::CommitmentFirst, shutdown_msg));
2965                 }
2966
2967                 let required_revoke = if msg.next_remote_commitment_number + 1 == INITIAL_COMMITMENT_NUMBER - self.cur_holder_commitment_transaction_number {
2968                         // Remote isn't waiting on any RevokeAndACK from us!
2969                         // Note that if we need to repeat our FundingLocked we'll do that in the next if block.
2970                         None
2971                 } else if msg.next_remote_commitment_number + 1 == (INITIAL_COMMITMENT_NUMBER - 1) - self.cur_holder_commitment_transaction_number {
2972                         if self.channel_state & (ChannelState::MonitorUpdateFailed as u32) != 0 {
2973                                 self.monitor_pending_revoke_and_ack = true;
2974                                 None
2975                         } else {
2976                                 Some(self.get_last_revoke_and_ack())
2977                         }
2978                 } else {
2979                         return Err(ChannelError::Close("Peer attempted to reestablish channel with a very old local commitment transaction".to_owned()));
2980                 };
2981
2982                 // We increment cur_counterparty_commitment_transaction_number only upon receipt of
2983                 // revoke_and_ack, not on sending commitment_signed, so we add one if have
2984                 // AwaitingRemoteRevoke set, which indicates we sent a commitment_signed but haven't gotten
2985                 // the corresponding revoke_and_ack back yet.
2986                 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 };
2987
2988                 let resend_funding_locked = if msg.next_local_commitment_number == 1 && INITIAL_COMMITMENT_NUMBER - self.cur_holder_commitment_transaction_number == 1 {
2989                         // We should never have to worry about MonitorUpdateFailed resending FundingLocked
2990                         let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
2991                         Some(msgs::FundingLocked {
2992                                 channel_id: self.channel_id(),
2993                                 next_per_commitment_point,
2994                         })
2995                 } else { None };
2996
2997                 if msg.next_local_commitment_number == next_counterparty_commitment_number {
2998                         if required_revoke.is_some() {
2999                                 log_debug!(logger, "Reconnected channel {} with only lost outbound RAA", log_bytes!(self.channel_id()));
3000                         } else {
3001                                 log_debug!(logger, "Reconnected channel {} with no loss", log_bytes!(self.channel_id()));
3002                         }
3003
3004                         if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::MonitorUpdateFailed as u32)) == 0 {
3005                                 // Note that if in the future we no longer drop holding cell update_adds on peer
3006                                 // disconnect, this logic will need to be updated.
3007                                 for htlc_update in self.holding_cell_htlc_updates.iter() {
3008                                         if let &HTLCUpdateAwaitingACK::AddHTLC { .. } = htlc_update {
3009                                                 debug_assert!(false, "There shouldn't be any add-HTLCs in the holding cell now because they should have been dropped on peer disconnect. Panic here because said HTLCs won't be handled correctly.");
3010                                         }
3011                                 }
3012
3013                                 // We're up-to-date and not waiting on a remote revoke (if we are our
3014                                 // channel_reestablish should result in them sending a revoke_and_ack), but we may
3015                                 // have received some updates while we were disconnected. Free the holding cell
3016                                 // now!
3017                                 match self.free_holding_cell_htlcs(logger) {
3018                                         Err(ChannelError::Close(msg)) => return Err(ChannelError::Close(msg)),
3019                                         Err(ChannelError::Ignore(_)) | Err(ChannelError::CloseDelayBroadcast(_)) => panic!("Got non-channel-failing result from free_holding_cell_htlcs"),
3020                                         Ok((Some((commitment_update, monitor_update)), htlcs_to_fail)) => {
3021                                                 // If in the future we no longer drop holding cell update_adds on peer
3022                                                 // disconnect, we may be handed some HTLCs to fail backwards here.
3023                                                 assert!(htlcs_to_fail.is_empty());
3024                                                 return Ok((resend_funding_locked, required_revoke, Some(commitment_update), Some(monitor_update), self.resend_order.clone(), shutdown_msg));
3025                                         },
3026                                         Ok((None, htlcs_to_fail)) => {
3027                                                 // If in the future we no longer drop holding cell update_adds on peer
3028                                                 // disconnect, we may be handed some HTLCs to fail backwards here.
3029                                                 assert!(htlcs_to_fail.is_empty());
3030                                                 return Ok((resend_funding_locked, required_revoke, None, None, self.resend_order.clone(), shutdown_msg));
3031                                         },
3032                                 }
3033                         } else {
3034                                 return Ok((resend_funding_locked, required_revoke, None, None, self.resend_order.clone(), shutdown_msg));
3035                         }
3036                 } else if msg.next_local_commitment_number == next_counterparty_commitment_number - 1 {
3037                         if required_revoke.is_some() {
3038                                 log_debug!(logger, "Reconnected channel {} with lost outbound RAA and lost remote commitment tx", log_bytes!(self.channel_id()));
3039                         } else {
3040                                 log_debug!(logger, "Reconnected channel {} with only lost remote commitment tx", log_bytes!(self.channel_id()));
3041                         }
3042
3043                         if self.channel_state & (ChannelState::MonitorUpdateFailed as u32) != 0 {
3044                                 self.monitor_pending_commitment_signed = true;
3045                                 return Ok((resend_funding_locked, None, None, None, self.resend_order.clone(), shutdown_msg));
3046                         }
3047
3048                         return Ok((resend_funding_locked, required_revoke, Some(self.get_last_commitment_update(logger)), None, self.resend_order.clone(), shutdown_msg));
3049                 } else {
3050                         return Err(ChannelError::Close("Peer attempted to reestablish channel with a very old remote commitment transaction".to_owned()));
3051                 }
3052         }
3053
3054         fn maybe_propose_first_closing_signed<F: Deref>(&mut self, fee_estimator: &F) -> Option<msgs::ClosingSigned>
3055                 where F::Target: FeeEstimator
3056         {
3057                 if !self.is_outbound() || !self.pending_inbound_htlcs.is_empty() || !self.pending_outbound_htlcs.is_empty() ||
3058                                 self.channel_state & (BOTH_SIDES_SHUTDOWN_MASK | ChannelState::AwaitingRemoteRevoke as u32) != BOTH_SIDES_SHUTDOWN_MASK ||
3059                                 self.last_sent_closing_fee.is_some() || self.pending_update_fee.is_some() {
3060                         return None;
3061                 }
3062
3063                 let mut proposed_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background);
3064                 if self.feerate_per_kw > proposed_feerate {
3065                         proposed_feerate = self.feerate_per_kw;
3066                 }
3067                 let tx_weight = self.get_closing_transaction_weight(Some(&self.get_closing_scriptpubkey()), Some(self.counterparty_shutdown_scriptpubkey.as_ref().unwrap()));
3068                 let proposed_total_fee_satoshis = proposed_feerate as u64 * tx_weight / 1000;
3069
3070                 let (closing_tx, total_fee_satoshis) = self.build_closing_transaction(proposed_total_fee_satoshis, false);
3071                 let sig = self.holder_signer
3072                         .sign_closing_transaction(&closing_tx, &self.secp_ctx)
3073                         .ok();
3074                 assert!(closing_tx.get_weight() as u64 <= tx_weight);
3075                 if sig.is_none() { return None; }
3076
3077                 self.last_sent_closing_fee = Some((proposed_feerate, total_fee_satoshis, sig.clone().unwrap()));
3078                 Some(msgs::ClosingSigned {
3079                         channel_id: self.channel_id,
3080                         fee_satoshis: total_fee_satoshis,
3081                         signature: sig.unwrap(),
3082                 })
3083         }
3084
3085         pub fn shutdown<F: Deref>(&mut self, fee_estimator: &F, their_features: &InitFeatures, msg: &msgs::Shutdown) -> Result<(Option<msgs::Shutdown>, Option<msgs::ClosingSigned>, Vec<(HTLCSource, PaymentHash)>), ChannelError>
3086                 where F::Target: FeeEstimator
3087         {
3088                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
3089                         return Err(ChannelError::Close("Peer sent shutdown when we needed a channel_reestablish".to_owned()));
3090                 }
3091                 if self.channel_state < ChannelState::FundingSent as u32 {
3092                         // Spec says we should fail the connection, not the channel, but that's nonsense, there
3093                         // are plenty of reasons you may want to fail a channel pre-funding, and spec says you
3094                         // can do that via error message without getting a connection fail anyway...
3095                         return Err(ChannelError::Close("Peer sent shutdown pre-funding generation".to_owned()));
3096                 }
3097                 for htlc in self.pending_inbound_htlcs.iter() {
3098                         if let InboundHTLCState::RemoteAnnounced(_) = htlc.state {
3099                                 return Err(ChannelError::Close("Got shutdown with remote pending HTLCs".to_owned()));
3100                         }
3101                 }
3102                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
3103
3104                 if is_unsupported_shutdown_script(&their_features, &msg.scriptpubkey) {
3105                         return Err(ChannelError::Close(format!("Got a nonstandard scriptpubkey ({}) from remote peer", msg.scriptpubkey.to_bytes().to_hex())));
3106                 }
3107
3108                 if self.counterparty_shutdown_scriptpubkey.is_some() {
3109                         if Some(&msg.scriptpubkey) != self.counterparty_shutdown_scriptpubkey.as_ref() {
3110                                 return Err(ChannelError::Close(format!("Got shutdown request with a scriptpubkey ({}) which did not match their previous scriptpubkey.", msg.scriptpubkey.to_bytes().to_hex())));
3111                         }
3112                 } else {
3113                         self.counterparty_shutdown_scriptpubkey = Some(msg.scriptpubkey.clone());
3114                 }
3115
3116                 // From here on out, we may not fail!
3117
3118                 self.channel_state |= ChannelState::RemoteShutdownSent as u32;
3119                 self.update_time_counter += 1;
3120
3121                 // We can't send our shutdown until we've committed all of our pending HTLCs, but the
3122                 // remote side is unlikely to accept any new HTLCs, so we go ahead and "free" any holding
3123                 // cell HTLCs and return them to fail the payment.
3124                 self.holding_cell_update_fee = None;
3125                 let mut dropped_outbound_htlcs = Vec::with_capacity(self.holding_cell_htlc_updates.len());
3126                 self.holding_cell_htlc_updates.retain(|htlc_update| {
3127                         match htlc_update {
3128                                 &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, ref source, .. } => {
3129                                         dropped_outbound_htlcs.push((source.clone(), payment_hash.clone()));
3130                                         false
3131                                 },
3132                                 _ => true
3133                         }
3134                 });
3135                 // If we have any LocalAnnounced updates we'll probably just get back a update_fail_htlc
3136                 // immediately after the commitment dance, but we can send a Shutdown cause we won't send
3137                 // any further commitment updates after we set LocalShutdownSent.
3138
3139                 let shutdown = if (self.channel_state & ChannelState::LocalShutdownSent as u32) == ChannelState::LocalShutdownSent as u32 {
3140                         None
3141                 } else {
3142                         Some(msgs::Shutdown {
3143                                 channel_id: self.channel_id,
3144                                 scriptpubkey: self.get_closing_scriptpubkey(),
3145                         })
3146                 };
3147
3148                 self.channel_state |= ChannelState::LocalShutdownSent as u32;
3149                 self.update_time_counter += 1;
3150
3151                 Ok((shutdown, self.maybe_propose_first_closing_signed(fee_estimator), dropped_outbound_htlcs))
3152         }
3153
3154         fn build_signed_closing_transaction(&self, tx: &mut Transaction, counterparty_sig: &Signature, sig: &Signature) {
3155                 if tx.input.len() != 1 { panic!("Tried to sign closing transaction that had input count != 1!"); }
3156                 if tx.input[0].witness.len() != 0 { panic!("Tried to re-sign closing transaction"); }
3157                 if tx.output.len() > 2 { panic!("Tried to sign bogus closing transaction"); }
3158
3159                 tx.input[0].witness.push(Vec::new()); // First is the multisig dummy
3160
3161                 let funding_key = self.get_holder_pubkeys().funding_pubkey.serialize();
3162                 let counterparty_funding_key = self.counterparty_funding_pubkey().serialize();
3163                 if funding_key[..] < counterparty_funding_key[..] {
3164                         tx.input[0].witness.push(sig.serialize_der().to_vec());
3165                         tx.input[0].witness.push(counterparty_sig.serialize_der().to_vec());
3166                 } else {
3167                         tx.input[0].witness.push(counterparty_sig.serialize_der().to_vec());
3168                         tx.input[0].witness.push(sig.serialize_der().to_vec());
3169                 }
3170                 tx.input[0].witness[1].push(SigHashType::All as u8);
3171                 tx.input[0].witness[2].push(SigHashType::All as u8);
3172
3173                 tx.input[0].witness.push(self.get_funding_redeemscript().into_bytes());
3174         }
3175
3176         pub fn closing_signed<F: Deref>(&mut self, fee_estimator: &F, msg: &msgs::ClosingSigned) -> Result<(Option<msgs::ClosingSigned>, Option<Transaction>), ChannelError>
3177                 where F::Target: FeeEstimator
3178         {
3179                 if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK != BOTH_SIDES_SHUTDOWN_MASK {
3180                         return Err(ChannelError::Close("Remote end sent us a closing_signed before both sides provided a shutdown".to_owned()));
3181                 }
3182                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
3183                         return Err(ChannelError::Close("Peer sent closing_signed when we needed a channel_reestablish".to_owned()));
3184                 }
3185                 if !self.pending_inbound_htlcs.is_empty() || !self.pending_outbound_htlcs.is_empty() {
3186                         return Err(ChannelError::Close("Remote end sent us a closing_signed while there were still pending HTLCs".to_owned()));
3187                 }
3188                 if msg.fee_satoshis > 21_000_000 * 1_0000_0000 { //this is required to stop potential overflow in build_closing_transaction
3189                         return Err(ChannelError::Close("Remote tried to send us a closing tx with > 21 million BTC fee".to_owned()));
3190                 }
3191
3192                 let funding_redeemscript = self.get_funding_redeemscript();
3193                 let (mut closing_tx, used_total_fee) = self.build_closing_transaction(msg.fee_satoshis, false);
3194                 if used_total_fee != msg.fee_satoshis {
3195                         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)));
3196                 }
3197                 let mut sighash = hash_to_message!(&bip143::SigHashCache::new(&closing_tx).signature_hash(0, &funding_redeemscript, self.channel_value_satoshis, SigHashType::All)[..]);
3198
3199                 match self.secp_ctx.verify(&sighash, &msg.signature, &self.get_counterparty_pubkeys().funding_pubkey) {
3200                         Ok(_) => {},
3201                         Err(_e) => {
3202                                 // The remote end may have decided to revoke their output due to inconsistent dust
3203                                 // limits, so check for that case by re-checking the signature here.
3204                                 closing_tx = self.build_closing_transaction(msg.fee_satoshis, true).0;
3205                                 sighash = hash_to_message!(&bip143::SigHashCache::new(&closing_tx).signature_hash(0, &funding_redeemscript, self.channel_value_satoshis, SigHashType::All)[..]);
3206                                 secp_check!(self.secp_ctx.verify(&sighash, &msg.signature, self.counterparty_funding_pubkey()), "Invalid closing tx signature from peer".to_owned());
3207                         },
3208                 };
3209
3210                 let closing_tx_max_weight = self.get_closing_transaction_weight(
3211                         if let Some(oup) = closing_tx.output.get(0) { Some(&oup.script_pubkey) } else { None },
3212                         if let Some(oup) = closing_tx.output.get(1) { Some(&oup.script_pubkey) } else { None });
3213                 if let Some((_, last_fee, sig)) = self.last_sent_closing_fee {
3214                         if last_fee == msg.fee_satoshis {
3215                                 self.build_signed_closing_transaction(&mut closing_tx, &msg.signature, &sig);
3216                                 assert!(closing_tx.get_weight() as u64 <= closing_tx_max_weight);
3217                                 debug_assert!(closing_tx.get_weight() as u64 >= closing_tx_max_weight - 2);
3218                                 self.channel_state = ChannelState::ShutdownComplete as u32;
3219                                 self.update_time_counter += 1;
3220                                 return Ok((None, Some(closing_tx)));
3221                         }
3222                 }
3223
3224                 macro_rules! propose_new_feerate {
3225                         ($new_feerate: expr) => {
3226                                 let tx_weight = self.get_closing_transaction_weight(Some(&self.get_closing_scriptpubkey()), Some(self.counterparty_shutdown_scriptpubkey.as_ref().unwrap()));
3227                                 let (closing_tx, used_total_fee) = self.build_closing_transaction($new_feerate as u64 * tx_weight / 1000, false);
3228                                 let sig = self.holder_signer
3229                                         .sign_closing_transaction(&closing_tx, &self.secp_ctx)
3230                                         .map_err(|_| ChannelError::Close("External signer refused to sign closing transaction".to_owned()))?;
3231                                 assert!(closing_tx.get_weight() as u64 <= tx_weight);
3232                                 self.last_sent_closing_fee = Some(($new_feerate, used_total_fee, sig.clone()));
3233                                 return Ok((Some(msgs::ClosingSigned {
3234                                         channel_id: self.channel_id,
3235                                         fee_satoshis: used_total_fee,
3236                                         signature: sig,
3237                                 }), None))
3238                         }
3239                 }
3240
3241                 let mut min_feerate = 253;
3242                 if self.is_outbound() {
3243                         let max_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Normal);
3244                         if (msg.fee_satoshis as u64) > max_feerate as u64 * closing_tx_max_weight / 1000 {
3245                                 if let Some((last_feerate, _, _)) = self.last_sent_closing_fee {
3246                                         if max_feerate <= last_feerate {
3247                                                 return Err(ChannelError::Close(format!("Unable to come to consensus about closing feerate, remote wanted something higher ({}) than our Normal feerate ({})", last_feerate, max_feerate)));
3248                                         }
3249                                 }
3250                                 propose_new_feerate!(max_feerate);
3251                         }
3252                 } else {
3253                         min_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background);
3254                 }
3255                 if (msg.fee_satoshis as u64) < min_feerate as u64 * closing_tx_max_weight / 1000 {
3256                         if let Some((last_feerate, _, _)) = self.last_sent_closing_fee {
3257                                 if min_feerate >= last_feerate {
3258                                         return Err(ChannelError::Close(format!("Unable to come to consensus about closing feerate, remote wanted something lower ({}) than our Background feerate ({}).", last_feerate, min_feerate)));
3259                                 }
3260                         }
3261                         propose_new_feerate!(min_feerate);
3262                 }
3263
3264                 let sig = self.holder_signer
3265                         .sign_closing_transaction(&closing_tx, &self.secp_ctx)
3266                         .map_err(|_| ChannelError::Close("External signer refused to sign closing transaction".to_owned()))?;
3267                 self.build_signed_closing_transaction(&mut closing_tx, &msg.signature, &sig);
3268                 assert!(closing_tx.get_weight() as u64 <= closing_tx_max_weight);
3269                 debug_assert!(closing_tx.get_weight() as u64 >= closing_tx_max_weight - 2);
3270
3271                 self.channel_state = ChannelState::ShutdownComplete as u32;
3272                 self.update_time_counter += 1;
3273
3274                 Ok((Some(msgs::ClosingSigned {
3275                         channel_id: self.channel_id,
3276                         fee_satoshis: msg.fee_satoshis,
3277                         signature: sig,
3278                 }), Some(closing_tx)))
3279         }
3280
3281         // Public utilities:
3282
3283         pub fn channel_id(&self) -> [u8; 32] {
3284                 self.channel_id
3285         }
3286
3287         /// Gets the "user_id" value passed into the construction of this channel. It has no special
3288         /// meaning and exists only to allow users to have a persistent identifier of a channel.
3289         pub fn get_user_id(&self) -> u64 {
3290                 self.user_id
3291         }
3292
3293         /// Guaranteed to be Some after both FundingLocked messages have been exchanged (and, thus,
3294         /// is_usable() returns true).
3295         /// Allowed in any state (including after shutdown)
3296         pub fn get_short_channel_id(&self) -> Option<u64> {
3297                 self.short_channel_id
3298         }
3299
3300         /// Returns the funding_txo we either got from our peer, or were given by
3301         /// get_outbound_funding_created.
3302         pub fn get_funding_txo(&self) -> Option<OutPoint> {
3303                 self.channel_transaction_parameters.funding_outpoint
3304         }
3305
3306         fn get_holder_selected_contest_delay(&self) -> u16 {
3307                 self.channel_transaction_parameters.holder_selected_contest_delay
3308         }
3309
3310         fn get_holder_pubkeys(&self) -> &ChannelPublicKeys {
3311                 &self.channel_transaction_parameters.holder_pubkeys
3312         }
3313
3314         fn get_counterparty_selected_contest_delay(&self) -> u16 {
3315                 self.channel_transaction_parameters.counterparty_parameters.as_ref().unwrap().selected_contest_delay
3316         }
3317
3318         fn get_counterparty_pubkeys(&self) -> &ChannelPublicKeys {
3319                 &self.channel_transaction_parameters.counterparty_parameters.as_ref().unwrap().pubkeys
3320         }
3321
3322         /// Allowed in any state (including after shutdown)
3323         pub fn get_counterparty_node_id(&self) -> PublicKey {
3324                 self.counterparty_node_id
3325         }
3326
3327         /// Allowed in any state (including after shutdown)
3328         #[cfg(test)]
3329         pub fn get_holder_htlc_minimum_msat(&self) -> u64 {
3330                 self.holder_htlc_minimum_msat
3331         }
3332
3333         /// Allowed in any state (including after shutdown)
3334         pub fn get_announced_htlc_max_msat(&self) -> u64 {
3335                 return cmp::min(
3336                         // Upper bound by capacity. We make it a bit less than full capacity to prevent attempts
3337                         // to use full capacity. This is an effort to reduce routing failures, because in many cases
3338                         // channel might have been used to route very small values (either by honest users or as DoS).
3339                         self.channel_value_satoshis * 1000 * 9 / 10,
3340
3341                         Channel::<Signer>::get_holder_max_htlc_value_in_flight_msat(self.channel_value_satoshis)
3342                 );
3343         }
3344
3345         /// Allowed in any state (including after shutdown)
3346         pub fn get_counterparty_htlc_minimum_msat(&self) -> u64 {
3347                 self.counterparty_htlc_minimum_msat
3348         }
3349
3350         pub fn get_value_satoshis(&self) -> u64 {
3351                 self.channel_value_satoshis
3352         }
3353
3354         pub fn get_fee_proportional_millionths(&self) -> u32 {
3355                 self.config.fee_proportional_millionths
3356         }
3357
3358         pub fn get_cltv_expiry_delta(&self) -> u16 {
3359                 cmp::max(self.config.cltv_expiry_delta, MIN_CLTV_EXPIRY_DELTA)
3360         }
3361
3362         #[cfg(test)]
3363         pub fn get_feerate(&self) -> u32 {
3364                 self.feerate_per_kw
3365         }
3366
3367         pub fn get_cur_holder_commitment_transaction_number(&self) -> u64 {
3368                 self.cur_holder_commitment_transaction_number + 1
3369         }
3370
3371         pub fn get_cur_counterparty_commitment_transaction_number(&self) -> u64 {
3372                 self.cur_counterparty_commitment_transaction_number + 1 - if self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32) != 0 { 1 } else { 0 }
3373         }
3374
3375         pub fn get_revoked_counterparty_commitment_transaction_number(&self) -> u64 {
3376                 self.cur_counterparty_commitment_transaction_number + 2
3377         }
3378
3379         #[cfg(test)]
3380         pub fn get_signer(&self) -> &Signer {
3381                 &self.holder_signer
3382         }
3383
3384         #[cfg(test)]
3385         pub fn get_value_stat(&self) -> ChannelValueStat {
3386                 ChannelValueStat {
3387                         value_to_self_msat: self.value_to_self_msat,
3388                         channel_value_msat: self.channel_value_satoshis * 1000,
3389                         channel_reserve_msat: self.counterparty_selected_channel_reserve_satoshis * 1000,
3390                         pending_outbound_htlcs_amount_msat: self.pending_outbound_htlcs.iter().map(|ref h| h.amount_msat).sum::<u64>(),
3391                         pending_inbound_htlcs_amount_msat: self.pending_inbound_htlcs.iter().map(|ref h| h.amount_msat).sum::<u64>(),
3392                         holding_cell_outbound_amount_msat: {
3393                                 let mut res = 0;
3394                                 for h in self.holding_cell_htlc_updates.iter() {
3395                                         match h {
3396                                                 &HTLCUpdateAwaitingACK::AddHTLC{amount_msat, .. } => {
3397                                                         res += amount_msat;
3398                                                 }
3399                                                 _ => {}
3400                                         }
3401                                 }
3402                                 res
3403                         },
3404                         counterparty_max_htlc_value_in_flight_msat: self.counterparty_max_htlc_value_in_flight_msat,
3405                         counterparty_dust_limit_msat: self.counterparty_dust_limit_satoshis * 1000,
3406                 }
3407         }
3408
3409         /// Allowed in any state (including after shutdown)
3410         pub fn get_update_time_counter(&self) -> u32 {
3411                 self.update_time_counter
3412         }
3413
3414         pub fn get_latest_monitor_update_id(&self) -> u64 {
3415                 self.latest_monitor_update_id
3416         }
3417
3418         pub fn should_announce(&self) -> bool {
3419                 self.config.announced_channel
3420         }
3421
3422         pub fn is_outbound(&self) -> bool {
3423                 self.channel_transaction_parameters.is_outbound_from_holder
3424         }
3425
3426         /// Gets the fee we'd want to charge for adding an HTLC output to this Channel
3427         /// Allowed in any state (including after shutdown)
3428         pub fn get_holder_fee_base_msat<F: Deref>(&self, fee_estimator: &F) -> u32
3429                 where F::Target: FeeEstimator
3430         {
3431                 // For lack of a better metric, we calculate what it would cost to consolidate the new HTLC
3432                 // output value back into a transaction with the regular channel output:
3433
3434                 // the fee cost of the HTLC-Success/HTLC-Timeout transaction:
3435                 let mut res = self.feerate_per_kw as u64 * cmp::max(HTLC_TIMEOUT_TX_WEIGHT, HTLC_SUCCESS_TX_WEIGHT) / 1000;
3436
3437                 if self.is_outbound() {
3438                         // + the marginal fee increase cost to us in the commitment transaction:
3439                         res += self.feerate_per_kw as u64 * COMMITMENT_TX_WEIGHT_PER_HTLC / 1000;
3440                 }
3441
3442                 // + the marginal cost of an input which spends the HTLC-Success/HTLC-Timeout output:
3443                 res += fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Normal) as u64 * SPENDING_INPUT_FOR_A_OUTPUT_WEIGHT / 1000;
3444
3445                 res as u32
3446         }
3447
3448         /// Returns true if we've ever received a message from the remote end for this Channel
3449         pub fn have_received_message(&self) -> bool {
3450                 self.channel_state > (ChannelState::OurInitSent as u32)
3451         }
3452
3453         /// Returns true if this channel is fully established and not known to be closing.
3454         /// Allowed in any state (including after shutdown)
3455         pub fn is_usable(&self) -> bool {
3456                 let mask = ChannelState::ChannelFunded as u32 | BOTH_SIDES_SHUTDOWN_MASK;
3457                 (self.channel_state & mask) == (ChannelState::ChannelFunded as u32)
3458         }
3459
3460         /// Returns true if this channel is currently available for use. This is a superset of
3461         /// is_usable() and considers things like the channel being temporarily disabled.
3462         /// Allowed in any state (including after shutdown)
3463         pub fn is_live(&self) -> bool {
3464                 self.is_usable() && (self.channel_state & (ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32) == 0)
3465         }
3466
3467         /// Returns true if this channel has been marked as awaiting a monitor update to move forward.
3468         /// Allowed in any state (including after shutdown)
3469         pub fn is_awaiting_monitor_update(&self) -> bool {
3470                 (self.channel_state & ChannelState::MonitorUpdateFailed as u32) != 0
3471         }
3472
3473         /// Returns true if funding_created was sent/received.
3474         pub fn is_funding_initiated(&self) -> bool {
3475                 self.channel_state >= ChannelState::FundingSent as u32
3476         }
3477
3478         /// Returns true if this channel is fully shut down. True here implies that no further actions
3479         /// may/will be taken on this channel, and thus this object should be freed. Any future changes
3480         /// will be handled appropriately by the chain monitor.
3481         pub fn is_shutdown(&self) -> bool {
3482                 if (self.channel_state & ChannelState::ShutdownComplete as u32) == ChannelState::ShutdownComplete as u32  {
3483                         assert!(self.channel_state == ChannelState::ShutdownComplete as u32);
3484                         true
3485                 } else { false }
3486         }
3487
3488         pub fn to_disabled_staged(&mut self) {
3489                 self.network_sync = UpdateStatus::DisabledStaged;
3490         }
3491
3492         pub fn to_disabled_marked(&mut self) {
3493                 self.network_sync = UpdateStatus::DisabledMarked;
3494         }
3495
3496         pub fn to_fresh(&mut self) {
3497                 self.network_sync = UpdateStatus::Fresh;
3498         }
3499
3500         pub fn is_disabled_staged(&self) -> bool {
3501                 self.network_sync == UpdateStatus::DisabledStaged
3502         }
3503
3504         pub fn is_disabled_marked(&self) -> bool {
3505                 self.network_sync == UpdateStatus::DisabledMarked
3506         }
3507
3508         fn check_get_funding_locked(&mut self, height: u32) -> Option<msgs::FundingLocked> {
3509                 if self.funding_tx_confirmation_height == 0 {
3510                         return None;
3511                 }
3512
3513                 let funding_tx_confirmations = height as i64 - self.funding_tx_confirmation_height as i64 + 1;
3514                 if funding_tx_confirmations <= 0 {
3515                         self.funding_tx_confirmation_height = 0;
3516                 }
3517
3518                 if funding_tx_confirmations < self.minimum_depth as i64 {
3519                         return None;
3520                 }
3521
3522                 let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
3523                 let need_commitment_update = if non_shutdown_state == ChannelState::FundingSent as u32 {
3524                         self.channel_state |= ChannelState::OurFundingLocked as u32;
3525                         true
3526                 } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::TheirFundingLocked as u32) {
3527                         self.channel_state = ChannelState::ChannelFunded as u32 | (self.channel_state & MULTI_STATE_FLAGS);
3528                         self.update_time_counter += 1;
3529                         true
3530                 } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::OurFundingLocked as u32) {
3531                         // We got a reorg but not enough to trigger a force close, just ignore.
3532                         false
3533                 } else if self.channel_state < ChannelState::ChannelFunded as u32 {
3534                         panic!("Started confirming a channel in a state pre-FundingSent?: {}", self.channel_state);
3535                 } else {
3536                         // We got a reorg but not enough to trigger a force close, just ignore.
3537                         false
3538                 };
3539
3540                 if need_commitment_update {
3541                         if self.channel_state & (ChannelState::MonitorUpdateFailed as u32) == 0 {
3542                                 let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
3543                                 return Some(msgs::FundingLocked {
3544                                         channel_id: self.channel_id,
3545                                         next_per_commitment_point,
3546                                 });
3547                         } else {
3548                                 self.monitor_pending_funding_locked = true;
3549                         }
3550                 }
3551                 None
3552         }
3553
3554         /// When a transaction is confirmed, we check whether it is or spends the funding transaction
3555         /// In the first case, we store the confirmation height and calculating the short channel id.
3556         /// In the second, we simply return an Err indicating we need to be force-closed now.
3557         pub fn transactions_confirmed<L: Deref>(&mut self, block_hash: &BlockHash, height: u32, txdata: &TransactionData, logger: &L)
3558                         -> Result<Option<msgs::FundingLocked>, msgs::ErrorMessage> where L::Target: Logger {
3559                 let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
3560                 for &(index_in_block, tx) in txdata.iter() {
3561                         if let Some(funding_txo) = self.get_funding_txo() {
3562                                 // If we haven't yet sent a funding_locked, but are in FundingSent (ignoring
3563                                 // whether they've sent a funding_locked or not), check if we should send one.
3564                                 if non_shutdown_state & !(ChannelState::TheirFundingLocked as u32) == ChannelState::FundingSent as u32 {
3565                                         if tx.txid() == funding_txo.txid {
3566                                                 let txo_idx = funding_txo.index as usize;
3567                                                 if txo_idx >= tx.output.len() || tx.output[txo_idx].script_pubkey != self.get_funding_redeemscript().to_v0_p2wsh() ||
3568                                                                 tx.output[txo_idx].value != self.channel_value_satoshis {
3569                                                         if self.is_outbound() {
3570                                                                 // If we generated the funding transaction and it doesn't match what it
3571                                                                 // should, the client is really broken and we should just panic and
3572                                                                 // tell them off. That said, because hash collisions happen with high
3573                                                                 // probability in fuzztarget mode, if we're fuzzing we just close the
3574                                                                 // channel and move on.
3575                                                                 #[cfg(not(feature = "fuzztarget"))]
3576                                                                 panic!("Client called ChannelManager::funding_transaction_generated with bogus transaction!");
3577                                                         }
3578                                                         self.update_time_counter += 1;
3579                                                         return Err(msgs::ErrorMessage {
3580                                                                 channel_id: self.channel_id(),
3581                                                                 data: "funding tx had wrong script/value or output index".to_owned()
3582                                                         });
3583                                                 } else {
3584                                                         if self.is_outbound() {
3585                                                                 for input in tx.input.iter() {
3586                                                                         if input.witness.is_empty() {
3587                                                                                 // We generated a malleable funding transaction, implying we've
3588                                                                                 // just exposed ourselves to funds loss to our counterparty.
3589                                                                                 #[cfg(not(feature = "fuzztarget"))]
3590                                                                                 panic!("Client called ChannelManager::funding_transaction_generated with bogus transaction!");
3591                                                                         }
3592                                                                 }
3593                                                         }
3594                                                         self.funding_tx_confirmation_height = height;
3595                                                         self.funding_tx_confirmed_in = Some(*block_hash);
3596                                                         self.short_channel_id = match scid_from_parts(height as u64, index_in_block as u64, txo_idx as u64) {
3597                                                                 Ok(scid) => Some(scid),
3598                                                                 Err(_) => panic!("Block was bogus - either height was > 16 million, had > 16 million transactions, or had > 65k outputs"),
3599                                                         }
3600                                                 }
3601                                         }
3602                                         // If we allow 1-conf funding, we may need to check for funding_locked here and
3603                                         // send it immediately instead of waiting for a best_block_updated call (which
3604                                         // may have already happened for this block).
3605                                         if let Some(funding_locked) = self.check_get_funding_locked(height) {
3606                                                 return Ok(Some(funding_locked));
3607                                         }
3608                                 }
3609                                 for inp in tx.input.iter() {
3610                                         if inp.previous_output == funding_txo.into_bitcoin_outpoint() {
3611                                                 log_trace!(logger, "Detected channel-closing tx {} spending {}:{}, closing channel {}", tx.txid(), inp.previous_output.txid, inp.previous_output.vout, log_bytes!(self.channel_id()));
3612                                                 return Err(msgs::ErrorMessage {
3613                                                         channel_id: self.channel_id(),
3614                                                         data: "Commitment or closing transaction was confirmed on chain.".to_owned()
3615                                                 });
3616                                         }
3617                                 }
3618                         }
3619                 }
3620                 Ok(None)
3621         }
3622
3623         /// When a new block is connected, we check the height of the block against outbound holding
3624         /// cell HTLCs in case we need to give up on them prematurely and time them out. Everything
3625         /// else (e.g. commitment transaction broadcasts, HTLC transaction broadcasting, etc) is
3626         /// handled by the ChannelMonitor.
3627         ///
3628         /// If we return Err, the channel may have been closed, at which point the standard
3629         /// requirements apply - no calls may be made except those explicitly stated to be allowed
3630         /// post-shutdown.
3631         ///
3632         /// May return some HTLCs (and their payment_hash) which have timed out and should be failed
3633         /// back.
3634         pub fn best_block_updated(&mut self, height: u32, highest_header_time: u32) -> Result<(Option<msgs::FundingLocked>, Vec<(HTLCSource, PaymentHash)>), msgs::ErrorMessage> {
3635                 let mut timed_out_htlcs = Vec::new();
3636                 let unforwarded_htlc_cltv_limit = height + HTLC_FAIL_BACK_BUFFER;
3637                 self.holding_cell_htlc_updates.retain(|htlc_update| {
3638                         match htlc_update {
3639                                 &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, ref source, ref cltv_expiry, .. } => {
3640                                         if *cltv_expiry <= unforwarded_htlc_cltv_limit {
3641                                                 timed_out_htlcs.push((source.clone(), payment_hash.clone()));
3642                                                 false
3643                                         } else { true }
3644                                 },
3645                                 _ => true
3646                         }
3647                 });
3648
3649                 self.update_time_counter = cmp::max(self.update_time_counter, highest_header_time);
3650
3651                 if let Some(funding_locked) = self.check_get_funding_locked(height) {
3652                         return Ok((Some(funding_locked), timed_out_htlcs));
3653                 }
3654
3655                 let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
3656                 if non_shutdown_state >= ChannelState::ChannelFunded as u32 ||
3657                    (non_shutdown_state & ChannelState::OurFundingLocked as u32) == ChannelState::OurFundingLocked as u32 {
3658                         let mut funding_tx_confirmations = height as i64 - self.funding_tx_confirmation_height as i64 + 1;
3659                         if self.funding_tx_confirmation_height == 0 {
3660                                 // Note that check_get_funding_locked may reset funding_tx_confirmation_height to
3661                                 // zero if it has been reorged out, however in either case, our state flags
3662                                 // indicate we've already sent a funding_locked
3663                                 funding_tx_confirmations = 0;
3664                         }
3665
3666                         // If we've sent funding_locked (or have both sent and received funding_locked), and
3667                         // the funding transaction's confirmation count has dipped below minimum_depth / 2,
3668                         // close the channel and hope we can get the latest state on chain (because presumably
3669                         // the funding transaction is at least still in the mempool of most nodes).
3670                         if funding_tx_confirmations < self.minimum_depth as i64 / 2 {
3671                                 return Err(msgs::ErrorMessage {
3672                                         channel_id: self.channel_id(),
3673                                         data: format!("Funding transaction was un-confirmed. Locked at {} confs, now have {} confs.", self.minimum_depth, funding_tx_confirmations),
3674                                 });
3675                         }
3676                 }
3677
3678                 Ok((None, timed_out_htlcs))
3679         }
3680
3681         /// Indicates the funding transaction is no longer confirmed in the main chain. This may
3682         /// force-close the channel, but may also indicate a harmless reorganization of a block or two
3683         /// before the channel has reached funding_locked and we can just wait for more blocks.
3684         pub fn funding_transaction_unconfirmed(&mut self) -> Result<(), msgs::ErrorMessage> {
3685                 if self.funding_tx_confirmation_height != 0 {
3686                         // We handle the funding disconnection by calling best_block_updated with a height one
3687                         // below where our funding was connected, implying a reorg back to conf_height - 1.
3688                         let reorg_height = self.funding_tx_confirmation_height - 1;
3689                         // We use the time field to bump the current time we set on channel updates if its
3690                         // larger. If we don't know that time has moved forward, we can just set it to the last
3691                         // time we saw and it will be ignored.
3692                         let best_time = self.update_time_counter;
3693                         match self.best_block_updated(reorg_height, best_time) {
3694                                 Ok((funding_locked, timed_out_htlcs)) => {
3695                                         assert!(funding_locked.is_none(), "We can't generate a funding with 0 confirmations?");
3696                                         assert!(timed_out_htlcs.is_empty(), "We can't have accepted HTLCs with a timeout before our funding confirmation?");
3697                                         Ok(())
3698                                 },
3699                                 Err(e) => Err(e)
3700                         }
3701                 } else {
3702                         // We never learned about the funding confirmation anyway, just ignore
3703                         Ok(())
3704                 }
3705         }
3706
3707         // Methods to get unprompted messages to send to the remote end (or where we already returned
3708         // something in the handler for the message that prompted this message):
3709
3710         pub fn get_open_channel(&self, chain_hash: BlockHash) -> msgs::OpenChannel {
3711                 if !self.is_outbound() {
3712                         panic!("Tried to open a channel for an inbound channel?");
3713                 }
3714                 if self.channel_state != ChannelState::OurInitSent as u32 {
3715                         panic!("Cannot generate an open_channel after we've moved forward");
3716                 }
3717
3718                 if self.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
3719                         panic!("Tried to send an open_channel for a channel that has already advanced");
3720                 }
3721
3722                 let first_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
3723                 let keys = self.get_holder_pubkeys();
3724
3725                 msgs::OpenChannel {
3726                         chain_hash,
3727                         temporary_channel_id: self.channel_id,
3728                         funding_satoshis: self.channel_value_satoshis,
3729                         push_msat: self.channel_value_satoshis * 1000 - self.value_to_self_msat,
3730                         dust_limit_satoshis: self.holder_dust_limit_satoshis,
3731                         max_htlc_value_in_flight_msat: Channel::<Signer>::get_holder_max_htlc_value_in_flight_msat(self.channel_value_satoshis),
3732                         channel_reserve_satoshis: Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis),
3733                         htlc_minimum_msat: self.holder_htlc_minimum_msat,
3734                         feerate_per_kw: self.feerate_per_kw as u32,
3735                         to_self_delay: self.get_holder_selected_contest_delay(),
3736                         max_accepted_htlcs: OUR_MAX_HTLCS,
3737                         funding_pubkey: keys.funding_pubkey,
3738                         revocation_basepoint: keys.revocation_basepoint,
3739                         payment_point: keys.payment_point,
3740                         delayed_payment_basepoint: keys.delayed_payment_basepoint,
3741                         htlc_basepoint: keys.htlc_basepoint,
3742                         first_per_commitment_point,
3743                         channel_flags: if self.config.announced_channel {1} else {0},
3744                         shutdown_scriptpubkey: OptionalField::Present(if self.config.commit_upfront_shutdown_pubkey { self.get_closing_scriptpubkey() } else { Builder::new().into_script() })
3745                 }
3746         }
3747
3748         pub fn get_accept_channel(&self) -> msgs::AcceptChannel {
3749                 if self.is_outbound() {
3750                         panic!("Tried to send accept_channel for an outbound channel?");
3751                 }
3752                 if self.channel_state != (ChannelState::OurInitSent as u32) | (ChannelState::TheirInitSent as u32) {
3753                         panic!("Tried to send accept_channel after channel had moved forward");
3754                 }
3755                 if self.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
3756                         panic!("Tried to send an accept_channel for a channel that has already advanced");
3757                 }
3758
3759                 let first_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
3760                 let keys = self.get_holder_pubkeys();
3761
3762                 msgs::AcceptChannel {
3763                         temporary_channel_id: self.channel_id,
3764                         dust_limit_satoshis: self.holder_dust_limit_satoshis,
3765                         max_htlc_value_in_flight_msat: Channel::<Signer>::get_holder_max_htlc_value_in_flight_msat(self.channel_value_satoshis),
3766                         channel_reserve_satoshis: Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis),
3767                         htlc_minimum_msat: self.holder_htlc_minimum_msat,
3768                         minimum_depth: self.minimum_depth,
3769                         to_self_delay: self.get_holder_selected_contest_delay(),
3770                         max_accepted_htlcs: OUR_MAX_HTLCS,
3771                         funding_pubkey: keys.funding_pubkey,
3772                         revocation_basepoint: keys.revocation_basepoint,
3773                         payment_point: keys.payment_point,
3774                         delayed_payment_basepoint: keys.delayed_payment_basepoint,
3775                         htlc_basepoint: keys.htlc_basepoint,
3776                         first_per_commitment_point,
3777                         shutdown_scriptpubkey: OptionalField::Present(if self.config.commit_upfront_shutdown_pubkey { self.get_closing_scriptpubkey() } else { Builder::new().into_script() })
3778                 }
3779         }
3780
3781         /// If an Err is returned, it is a ChannelError::Close (for get_outbound_funding_created)
3782         fn get_outbound_funding_created_signature<L: Deref>(&mut self, logger: &L) -> Result<Signature, ChannelError> where L::Target: Logger {
3783                 let counterparty_keys = self.build_remote_transaction_keys()?;
3784                 let counterparty_initial_commitment_tx = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, false, self.feerate_per_kw, logger).0;
3785                 Ok(self.holder_signer.sign_counterparty_commitment(&counterparty_initial_commitment_tx, &self.secp_ctx)
3786                                 .map_err(|_| ChannelError::Close("Failed to get signatures for new commitment_signed".to_owned()))?.0)
3787         }
3788
3789         /// Updates channel state with knowledge of the funding transaction's txid/index, and generates
3790         /// a funding_created message for the remote peer.
3791         /// Panics if called at some time other than immediately after initial handshake, if called twice,
3792         /// or if called on an inbound channel.
3793         /// Note that channel_id changes during this call!
3794         /// Do NOT broadcast the funding transaction until after a successful funding_signed call!
3795         /// If an Err is returned, it is a ChannelError::Close.
3796         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 {
3797                 if !self.is_outbound() {
3798                         panic!("Tried to create outbound funding_created message on an inbound channel!");
3799                 }
3800                 if self.channel_state != (ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32) {
3801                         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)");
3802                 }
3803                 if self.commitment_secrets.get_min_seen_secret() != (1 << 48) ||
3804                                 self.cur_counterparty_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER ||
3805                                 self.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
3806                         panic!("Should not have advanced channel commitment tx numbers prior to funding_created");
3807                 }
3808
3809                 self.channel_transaction_parameters.funding_outpoint = Some(funding_txo);
3810                 self.holder_signer.ready_channel(&self.channel_transaction_parameters);
3811
3812                 let signature = match self.get_outbound_funding_created_signature(logger) {
3813                         Ok(res) => res,
3814                         Err(e) => {
3815                                 log_error!(logger, "Got bad signatures: {:?}!", e);
3816                                 self.channel_transaction_parameters.funding_outpoint = None;
3817                                 return Err(e);
3818                         }
3819                 };
3820
3821                 let temporary_channel_id = self.channel_id;
3822
3823                 // Now that we're past error-generating stuff, update our local state:
3824
3825                 self.channel_state = ChannelState::FundingCreated as u32;
3826                 self.channel_id = funding_txo.to_channel_id();
3827                 self.funding_transaction = Some(funding_transaction);
3828
3829                 Ok(msgs::FundingCreated {
3830                         temporary_channel_id,
3831                         funding_txid: funding_txo.txid,
3832                         funding_output_index: funding_txo.index,
3833                         signature
3834                 })
3835         }
3836
3837         /// Gets an UnsignedChannelAnnouncement, as well as a signature covering it using our
3838         /// bitcoin_key, if available, for this channel. The channel must be publicly announceable and
3839         /// available for use (have exchanged FundingLocked messages in both directions). Should be used
3840         /// for both loose and in response to an AnnouncementSignatures message from the remote peer.
3841         /// Will only fail if we're not in a state where channel_announcement may be sent (including
3842         /// closing).
3843         /// Note that the "channel must be funded" requirement is stricter than BOLT 7 requires - see
3844         /// https://github.com/lightningnetwork/lightning-rfc/issues/468
3845         pub fn get_channel_announcement(&self, node_id: PublicKey, chain_hash: BlockHash) -> Result<(msgs::UnsignedChannelAnnouncement, Signature), ChannelError> {
3846                 if !self.config.announced_channel {
3847                         return Err(ChannelError::Ignore("Channel is not available for public announcements".to_owned()));
3848                 }
3849                 if self.channel_state & (ChannelState::ChannelFunded as u32) == 0 {
3850                         return Err(ChannelError::Ignore("Cannot get a ChannelAnnouncement until the channel funding has been locked".to_owned()));
3851                 }
3852                 if (self.channel_state & (ChannelState::LocalShutdownSent as u32 | ChannelState::ShutdownComplete as u32)) != 0 {
3853                         return Err(ChannelError::Ignore("Cannot get a ChannelAnnouncement once the channel is closing".to_owned()));
3854                 }
3855
3856                 let were_node_one = node_id.serialize()[..] < self.counterparty_node_id.serialize()[..];
3857
3858                 let msg = msgs::UnsignedChannelAnnouncement {
3859                         features: ChannelFeatures::known(),
3860                         chain_hash,
3861                         short_channel_id: self.get_short_channel_id().unwrap(),
3862                         node_id_1: if were_node_one { node_id } else { self.get_counterparty_node_id() },
3863                         node_id_2: if were_node_one { self.get_counterparty_node_id() } else { node_id },
3864                         bitcoin_key_1: if were_node_one { self.get_holder_pubkeys().funding_pubkey } else { self.counterparty_funding_pubkey().clone() },
3865                         bitcoin_key_2: if were_node_one { self.counterparty_funding_pubkey().clone() } else { self.get_holder_pubkeys().funding_pubkey },
3866                         excess_data: Vec::new(),
3867                 };
3868
3869                 let sig = self.holder_signer.sign_channel_announcement(&msg, &self.secp_ctx)
3870                         .map_err(|_| ChannelError::Ignore("Signer rejected channel_announcement".to_owned()))?;
3871
3872                 Ok((msg, sig))
3873         }
3874
3875         /// May panic if called on a channel that wasn't immediately-previously
3876         /// self.remove_uncommitted_htlcs_and_mark_paused()'d
3877         pub fn get_channel_reestablish<L: Deref>(&self, logger: &L) -> msgs::ChannelReestablish where L::Target: Logger {
3878                 assert_eq!(self.channel_state & ChannelState::PeerDisconnected as u32, ChannelState::PeerDisconnected as u32);
3879                 assert_ne!(self.cur_counterparty_commitment_transaction_number, INITIAL_COMMITMENT_NUMBER);
3880                 // Prior to static_remotekey, my_current_per_commitment_point was critical to claiming
3881                 // current to_remote balances. However, it no longer has any use, and thus is now simply
3882                 // set to a dummy (but valid, as required by the spec) public key.
3883                 // fuzztarget mode marks a subset of pubkeys as invalid so that we can hit "invalid pubkey"
3884                 // branches, but we unwrap it below, so we arbitrarily select a dummy pubkey which is both
3885                 // valid, and valid in fuzztarget mode's arbitrary validity criteria:
3886                 let mut pk = [2; 33]; pk[1] = 0xff;
3887                 let dummy_pubkey = PublicKey::from_slice(&pk).unwrap();
3888                 let data_loss_protect = if self.cur_counterparty_commitment_transaction_number + 1 < INITIAL_COMMITMENT_NUMBER {
3889                         let remote_last_secret = self.commitment_secrets.get_secret(self.cur_counterparty_commitment_transaction_number + 2).unwrap();
3890                         log_trace!(logger, "Enough info to generate a Data Loss Protect with per_commitment_secret {}", log_bytes!(remote_last_secret));
3891                         OptionalField::Present(DataLossProtect {
3892                                 your_last_per_commitment_secret: remote_last_secret,
3893                                 my_current_per_commitment_point: dummy_pubkey
3894                         })
3895                 } else {
3896                         log_info!(logger, "Sending a data_loss_protect with no previous remote per_commitment_secret");
3897                         OptionalField::Present(DataLossProtect {
3898                                 your_last_per_commitment_secret: [0;32],
3899                                 my_current_per_commitment_point: dummy_pubkey,
3900                         })
3901                 };
3902                 msgs::ChannelReestablish {
3903                         channel_id: self.channel_id(),
3904                         // The protocol has two different commitment number concepts - the "commitment
3905                         // transaction number", which starts from 0 and counts up, and the "revocation key
3906                         // index" which starts at INITIAL_COMMITMENT_NUMBER and counts down. We track
3907                         // commitment transaction numbers by the index which will be used to reveal the
3908                         // revocation key for that commitment transaction, which means we have to convert them
3909                         // to protocol-level commitment numbers here...
3910
3911                         // next_local_commitment_number is the next commitment_signed number we expect to
3912                         // receive (indicating if they need to resend one that we missed).
3913                         next_local_commitment_number: INITIAL_COMMITMENT_NUMBER - self.cur_holder_commitment_transaction_number,
3914                         // We have to set next_remote_commitment_number to the next revoke_and_ack we expect to
3915                         // receive, however we track it by the next commitment number for a remote transaction
3916                         // (which is one further, as they always revoke previous commitment transaction, not
3917                         // the one we send) so we have to decrement by 1. Note that if
3918                         // cur_counterparty_commitment_transaction_number is INITIAL_COMMITMENT_NUMBER we will have
3919                         // dropped this channel on disconnect as it hasn't yet reached FundingSent so we can't
3920                         // overflow here.
3921                         next_remote_commitment_number: INITIAL_COMMITMENT_NUMBER - self.cur_counterparty_commitment_transaction_number - 1,
3922                         data_loss_protect,
3923                 }
3924         }
3925
3926
3927         // Send stuff to our remote peers:
3928
3929         /// Adds a pending outbound HTLC to this channel, note that you probably want
3930         /// send_htlc_and_commit instead cause you'll want both messages at once.
3931         /// This returns an option instead of a pure UpdateAddHTLC as we may be in a state where we are
3932         /// waiting on the remote peer to send us a revoke_and_ack during which time we cannot add new
3933         /// HTLCs on the wire or we wouldn't be able to determine what they actually ACK'ed.
3934         /// You MUST call send_commitment prior to any other calls on this Channel
3935         /// If an Err is returned, it's a ChannelError::Ignore!
3936         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> {
3937                 if (self.channel_state & (ChannelState::ChannelFunded as u32 | BOTH_SIDES_SHUTDOWN_MASK)) != (ChannelState::ChannelFunded as u32) {
3938                         return Err(ChannelError::Ignore("Cannot send HTLC until channel is fully established and we haven't started shutting down".to_owned()));
3939                 }
3940                 let channel_total_msat = self.channel_value_satoshis * 1000;
3941                 if amount_msat > channel_total_msat {
3942                         return Err(ChannelError::Ignore(format!("Cannot send amount {}, because it is more than the total value of the channel {}", amount_msat, channel_total_msat)));
3943                 }
3944
3945                 if amount_msat == 0 {
3946                         return Err(ChannelError::Ignore("Cannot send 0-msat HTLC".to_owned()));
3947                 }
3948
3949                 if amount_msat < self.counterparty_htlc_minimum_msat {
3950                         return Err(ChannelError::Ignore(format!("Cannot send less than their minimum HTLC value ({})", self.counterparty_htlc_minimum_msat)));
3951                 }
3952
3953                 if (self.channel_state & (ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32)) != 0 {
3954                         // Note that this should never really happen, if we're !is_live() on receipt of an
3955                         // incoming HTLC for relay will result in us rejecting the HTLC and we won't allow
3956                         // the user to send directly into a !is_live() channel. However, if we
3957                         // disconnected during the time the previous hop was doing the commitment dance we may
3958                         // end up getting here after the forwarding delay. In any case, returning an
3959                         // IgnoreError will get ChannelManager to do the right thing and fail backwards now.
3960                         return Err(ChannelError::Ignore("Cannot send an HTLC while disconnected/frozen for channel monitor update".to_owned()));
3961                 }
3962
3963                 let (outbound_htlc_count, htlc_outbound_value_msat) = self.get_outbound_pending_htlc_stats();
3964                 if outbound_htlc_count + 1 > self.counterparty_max_accepted_htlcs as u32 {
3965                         return Err(ChannelError::Ignore(format!("Cannot push more than their max accepted HTLCs ({})", self.counterparty_max_accepted_htlcs)));
3966                 }
3967                 // Check their_max_htlc_value_in_flight_msat
3968                 if htlc_outbound_value_msat + amount_msat > self.counterparty_max_htlc_value_in_flight_msat {
3969                         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)));
3970                 }
3971
3972                 if !self.is_outbound() {
3973                         // Check that we won't violate the remote channel reserve by adding this HTLC.
3974                         let counterparty_balance_msat = self.channel_value_satoshis * 1000 - self.value_to_self_msat;
3975                         let holder_selected_chan_reserve_msat = Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis);
3976                         let htlc_candidate = HTLCCandidate::new(amount_msat, HTLCInitiator::LocalOffered);
3977                         let counterparty_commit_tx_fee_msat = self.next_remote_commit_tx_fee_msat(htlc_candidate, None);
3978                         if counterparty_balance_msat < holder_selected_chan_reserve_msat + counterparty_commit_tx_fee_msat {
3979                                 return Err(ChannelError::Ignore("Cannot send value that would put counterparty balance under holder-announced channel reserve value".to_owned()));
3980                         }
3981                 }
3982
3983                 let pending_value_to_self_msat = self.value_to_self_msat - htlc_outbound_value_msat;
3984                 if pending_value_to_self_msat < amount_msat {
3985                         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)));
3986                 }
3987
3988                 // `2 *` and extra HTLC are for the fee spike buffer.
3989                 let commit_tx_fee_msat = if self.is_outbound() {
3990                         let htlc_candidate = HTLCCandidate::new(amount_msat, HTLCInitiator::LocalOffered);
3991                         2 * self.next_local_commit_tx_fee_msat(htlc_candidate, Some(()))
3992                 } else { 0 };
3993                 if pending_value_to_self_msat - amount_msat < commit_tx_fee_msat {
3994                         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)));
3995                 }
3996
3997                 // Check self.counterparty_selected_channel_reserve_satoshis (the amount we must keep as
3998                 // reserve for the remote to have something to claim if we misbehave)
3999                 let chan_reserve_msat = self.counterparty_selected_channel_reserve_satoshis * 1000;
4000                 if pending_value_to_self_msat - amount_msat - commit_tx_fee_msat < chan_reserve_msat {
4001                         return Err(ChannelError::Ignore(format!("Cannot send value that would put our balance under counterparty-announced channel reserve value ({})", chan_reserve_msat)));
4002                 }
4003
4004                 // Now update local state:
4005                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == (ChannelState::AwaitingRemoteRevoke as u32) {
4006                         self.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::AddHTLC {
4007                                 amount_msat,
4008                                 payment_hash,
4009                                 cltv_expiry,
4010                                 source,
4011                                 onion_routing_packet,
4012                         });
4013                         return Ok(None);
4014                 }
4015
4016                 self.pending_outbound_htlcs.push(OutboundHTLCOutput {
4017                         htlc_id: self.next_holder_htlc_id,
4018                         amount_msat,
4019                         payment_hash: payment_hash.clone(),
4020                         cltv_expiry,
4021                         state: OutboundHTLCState::LocalAnnounced(Box::new(onion_routing_packet.clone())),
4022                         source,
4023                 });
4024
4025                 let res = msgs::UpdateAddHTLC {
4026                         channel_id: self.channel_id,
4027                         htlc_id: self.next_holder_htlc_id,
4028                         amount_msat,
4029                         payment_hash,
4030                         cltv_expiry,
4031                         onion_routing_packet,
4032                 };
4033                 self.next_holder_htlc_id += 1;
4034
4035                 Ok(Some(res))
4036         }
4037
4038         /// Creates a signed commitment transaction to send to the remote peer.
4039         /// Always returns a ChannelError::Close if an immediately-preceding (read: the
4040         /// last call to this Channel) send_htlc returned Ok(Some(_)) and there is an Err.
4041         /// May panic if called except immediately after a successful, Ok(Some(_))-returning send_htlc.
4042         pub fn send_commitment<L: Deref>(&mut self, logger: &L) -> Result<(msgs::CommitmentSigned, ChannelMonitorUpdate), ChannelError> where L::Target: Logger {
4043                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
4044                         panic!("Cannot create commitment tx until channel is fully established");
4045                 }
4046                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == (ChannelState::AwaitingRemoteRevoke as u32) {
4047                         panic!("Cannot create commitment tx until remote revokes their previous commitment");
4048                 }
4049                 if (self.channel_state & (ChannelState::PeerDisconnected as u32)) == (ChannelState::PeerDisconnected as u32) {
4050                         panic!("Cannot create commitment tx while disconnected, as send_htlc will have returned an Err so a send_commitment precondition has been violated");
4051                 }
4052                 if (self.channel_state & (ChannelState::MonitorUpdateFailed as u32)) == (ChannelState::MonitorUpdateFailed as u32) {
4053                         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");
4054                 }
4055                 let mut have_updates = self.pending_update_fee.is_some();
4056                 for htlc in self.pending_outbound_htlcs.iter() {
4057                         if let OutboundHTLCState::LocalAnnounced(_) = htlc.state {
4058                                 have_updates = true;
4059                         }
4060                         if have_updates { break; }
4061                 }
4062                 for htlc in self.pending_inbound_htlcs.iter() {
4063                         if let InboundHTLCState::LocalRemoved(_) = htlc.state {
4064                                 have_updates = true;
4065                         }
4066                         if have_updates { break; }
4067                 }
4068                 if !have_updates {
4069                         panic!("Cannot create commitment tx until we have some updates to send");
4070                 }
4071                 self.send_commitment_no_status_check(logger)
4072         }
4073         /// Only fails in case of bad keys
4074         fn send_commitment_no_status_check<L: Deref>(&mut self, logger: &L) -> Result<(msgs::CommitmentSigned, ChannelMonitorUpdate), ChannelError> where L::Target: Logger {
4075                 // We can upgrade the status of some HTLCs that are waiting on a commitment, even if we
4076                 // fail to generate this, we still are at least at a position where upgrading their status
4077                 // is acceptable.
4078                 for htlc in self.pending_inbound_htlcs.iter_mut() {
4079                         let new_state = if let &InboundHTLCState::AwaitingRemoteRevokeToAnnounce(ref forward_info) = &htlc.state {
4080                                 Some(InboundHTLCState::AwaitingAnnouncedRemoteRevoke(forward_info.clone()))
4081                         } else { None };
4082                         if let Some(state) = new_state {
4083                                 htlc.state = state;
4084                         }
4085                 }
4086                 for htlc in self.pending_outbound_htlcs.iter_mut() {
4087                         if let Some(fail_reason) = if let &mut OutboundHTLCState::AwaitingRemoteRevokeToRemove(ref mut fail_reason) = &mut htlc.state {
4088                                 Some(fail_reason.take())
4089                         } else { None } {
4090                                 htlc.state = OutboundHTLCState::AwaitingRemovedRemoteRevoke(fail_reason);
4091                         }
4092                 }
4093                 self.resend_order = RAACommitmentOrder::RevokeAndACKFirst;
4094
4095                 let (res, counterparty_commitment_txid, htlcs) = match self.send_commitment_no_state_update(logger) {
4096                         Ok((res, (counterparty_commitment_tx, mut htlcs))) => {
4097                                 // Update state now that we've passed all the can-fail calls...
4098                                 let htlcs_no_ref: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)> =
4099                                         htlcs.drain(..).map(|(htlc, htlc_source)| (htlc, htlc_source.map(|source_ref| Box::new(source_ref.clone())))).collect();
4100                                 (res, counterparty_commitment_tx, htlcs_no_ref)
4101                         },
4102                         Err(e) => return Err(e),
4103                 };
4104
4105                 self.latest_monitor_update_id += 1;
4106                 let monitor_update = ChannelMonitorUpdate {
4107                         update_id: self.latest_monitor_update_id,
4108                         updates: vec![ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo {
4109                                 commitment_txid: counterparty_commitment_txid,
4110                                 htlc_outputs: htlcs.clone(),
4111                                 commitment_number: self.cur_counterparty_commitment_transaction_number,
4112                                 their_revocation_point: self.counterparty_cur_commitment_point.unwrap()
4113                         }]
4114                 };
4115                 self.channel_state |= ChannelState::AwaitingRemoteRevoke as u32;
4116                 Ok((res, monitor_update))
4117         }
4118
4119         /// Only fails in case of bad keys. Used for channel_reestablish commitment_signed generation
4120         /// when we shouldn't change HTLC/channel state.
4121         fn send_commitment_no_state_update<L: Deref>(&self, logger: &L) -> Result<(msgs::CommitmentSigned, (Txid, Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)>)), ChannelError> where L::Target: Logger {
4122                 let mut feerate_per_kw = self.feerate_per_kw;
4123                 if let Some(feerate) = self.pending_update_fee {
4124                         if self.is_outbound() {
4125                                 feerate_per_kw = feerate;
4126                         }
4127                 }
4128
4129                 let counterparty_keys = self.build_remote_transaction_keys()?;
4130                 let counterparty_commitment_tx = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, true, feerate_per_kw, logger);
4131                 let counterparty_commitment_txid = counterparty_commitment_tx.0.trust().txid();
4132                 let (signature, htlc_signatures);
4133
4134                 #[cfg(any(test, feature = "fuzztarget"))]
4135                 {
4136                         if !self.is_outbound() {
4137                                 let projected_commit_tx_info = self.next_remote_commitment_tx_fee_info_cached.lock().unwrap().take();
4138                                 *self.next_local_commitment_tx_fee_info_cached.lock().unwrap() = None;
4139                                 if let Some(info) = projected_commit_tx_info {
4140                                         let total_pending_htlcs = self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len();
4141                                         if info.total_pending_htlcs == total_pending_htlcs
4142                                                 && info.next_holder_htlc_id == self.next_holder_htlc_id
4143                                                 && info.next_counterparty_htlc_id == self.next_counterparty_htlc_id
4144                                                 && info.feerate == self.feerate_per_kw {
4145                                                         let actual_fee = self.commit_tx_fee_msat(counterparty_commitment_tx.1);
4146                                                         assert_eq!(actual_fee, info.fee);
4147                                                 }
4148                                 }
4149                         }
4150                 }
4151
4152                 {
4153                         let mut htlcs = Vec::with_capacity(counterparty_commitment_tx.2.len());
4154                         for &(ref htlc, _) in counterparty_commitment_tx.2.iter() {
4155                                 htlcs.push(htlc);
4156                         }
4157
4158                         let res = self.holder_signer.sign_counterparty_commitment(&counterparty_commitment_tx.0, &self.secp_ctx)
4159                                 .map_err(|_| ChannelError::Close("Failed to get signatures for new commitment_signed".to_owned()))?;
4160                         signature = res.0;
4161                         htlc_signatures = res.1;
4162
4163                         log_trace!(logger, "Signed remote commitment tx {} (txid {}) with redeemscript {} -> {}",
4164                                 encode::serialize_hex(&counterparty_commitment_tx.0.trust().built_transaction().transaction),
4165                                 &counterparty_commitment_txid,
4166                                 encode::serialize_hex(&self.get_funding_redeemscript()),
4167                                 log_bytes!(signature.serialize_compact()[..]));
4168
4169                         for (ref htlc_sig, ref htlc) in htlc_signatures.iter().zip(htlcs) {
4170                                 log_trace!(logger, "Signed remote HTLC tx {} with redeemscript {} with pubkey {} -> {}",
4171                                         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)),
4172                                         encode::serialize_hex(&chan_utils::get_htlc_redeemscript(&htlc, &counterparty_keys)),
4173                                         log_bytes!(counterparty_keys.broadcaster_htlc_key.serialize()),
4174                                         log_bytes!(htlc_sig.serialize_compact()[..]));
4175                         }
4176                 }
4177
4178                 Ok((msgs::CommitmentSigned {
4179                         channel_id: self.channel_id,
4180                         signature,
4181                         htlc_signatures,
4182                 }, (counterparty_commitment_txid, counterparty_commitment_tx.2)))
4183         }
4184
4185         /// Adds a pending outbound HTLC to this channel, and creates a signed commitment transaction
4186         /// to send to the remote peer in one go.
4187         /// Shorthand for calling send_htlc() followed by send_commitment(), see docs on those for
4188         /// more info.
4189         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 {
4190                 match self.send_htlc(amount_msat, payment_hash, cltv_expiry, source, onion_routing_packet)? {
4191                         Some(update_add_htlc) => {
4192                                 let (commitment_signed, monitor_update) = self.send_commitment_no_status_check(logger)?;
4193                                 Ok(Some((update_add_htlc, commitment_signed, monitor_update)))
4194                         },
4195                         None => Ok(None)
4196                 }
4197         }
4198
4199         /// Get forwarding information for the counterparty.
4200         pub fn counterparty_forwarding_info(&self) -> Option<CounterpartyForwardingInfo> {
4201                 self.counterparty_forwarding_info.clone()
4202         }
4203
4204         pub fn channel_update(&mut self, msg: &msgs::ChannelUpdate) -> Result<(), ChannelError> {
4205                 let usable_channel_value_msat = (self.channel_value_satoshis - self.counterparty_selected_channel_reserve_satoshis) * 1000;
4206                 if msg.contents.htlc_minimum_msat >= usable_channel_value_msat {
4207                         return Err(ChannelError::Close("Minimum htlc value is greater than channel value".to_string()));
4208                 }
4209                 self.counterparty_forwarding_info = Some(CounterpartyForwardingInfo {
4210                         fee_base_msat: msg.contents.fee_base_msat,
4211                         fee_proportional_millionths: msg.contents.fee_proportional_millionths,
4212                         cltv_expiry_delta: msg.contents.cltv_expiry_delta
4213                 });
4214
4215                 Ok(())
4216         }
4217
4218         /// Begins the shutdown process, getting a message for the remote peer and returning all
4219         /// holding cell HTLCs for payment failure.
4220         pub fn get_shutdown(&mut self) -> Result<(msgs::Shutdown, Vec<(HTLCSource, PaymentHash)>), APIError> {
4221                 for htlc in self.pending_outbound_htlcs.iter() {
4222                         if let OutboundHTLCState::LocalAnnounced(_) = htlc.state {
4223                                 return Err(APIError::APIMisuseError{err: "Cannot begin shutdown with pending HTLCs. Process pending events first".to_owned()});
4224                         }
4225                 }
4226                 if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK != 0 {
4227                         if (self.channel_state & ChannelState::LocalShutdownSent as u32) == ChannelState::LocalShutdownSent as u32 {
4228                                 return Err(APIError::APIMisuseError{err: "Shutdown already in progress".to_owned()});
4229                         }
4230                         else if (self.channel_state & ChannelState::RemoteShutdownSent as u32) == ChannelState::RemoteShutdownSent as u32 {
4231                                 return Err(APIError::ChannelUnavailable{err: "Shutdown already in progress by remote".to_owned()});
4232                         }
4233                 }
4234                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
4235                 if self.channel_state & (ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32) != 0 {
4236                         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()});
4237                 }
4238
4239                 let closing_script = self.get_closing_scriptpubkey();
4240
4241                 // From here on out, we may not fail!
4242                 if self.channel_state < ChannelState::FundingSent as u32 {
4243                         self.channel_state = ChannelState::ShutdownComplete as u32;
4244                 } else {
4245                         self.channel_state |= ChannelState::LocalShutdownSent as u32;
4246                 }
4247                 self.update_time_counter += 1;
4248
4249                 // Go ahead and drop holding cell updates as we'd rather fail payments than wait to send
4250                 // our shutdown until we've committed all of the pending changes.
4251                 self.holding_cell_update_fee = None;
4252                 let mut dropped_outbound_htlcs = Vec::with_capacity(self.holding_cell_htlc_updates.len());
4253                 self.holding_cell_htlc_updates.retain(|htlc_update| {
4254                         match htlc_update {
4255                                 &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, ref source, .. } => {
4256                                         dropped_outbound_htlcs.push((source.clone(), payment_hash.clone()));
4257                                         false
4258                                 },
4259                                 _ => true
4260                         }
4261                 });
4262
4263                 Ok((msgs::Shutdown {
4264                         channel_id: self.channel_id,
4265                         scriptpubkey: closing_script,
4266                 }, dropped_outbound_htlcs))
4267         }
4268
4269         /// Gets the latest commitment transaction and any dependent transactions for relay (forcing
4270         /// shutdown of this channel - no more calls into this Channel may be made afterwards except
4271         /// those explicitly stated to be allowed after shutdown completes, eg some simple getters).
4272         /// Also returns the list of payment_hashes for channels which we can safely fail backwards
4273         /// immediately (others we will have to allow to time out).
4274         pub fn force_shutdown(&mut self, should_broadcast: bool) -> (Option<(OutPoint, ChannelMonitorUpdate)>, Vec<(HTLCSource, PaymentHash)>) {
4275                 // Note that we MUST only generate a monitor update that indicates force-closure - we're
4276                 // called during initialization prior to the chain_monitor in the encompassing ChannelManager
4277                 // being fully configured in some cases. Thus, its likely any monitor events we generate will
4278                 // be delayed in being processed! See the docs for `ChannelManagerReadArgs` for more.
4279                 assert!(self.channel_state != ChannelState::ShutdownComplete as u32);
4280
4281                 // We go ahead and "free" any holding cell HTLCs or HTLCs we haven't yet committed to and
4282                 // return them to fail the payment.
4283                 let mut dropped_outbound_htlcs = Vec::with_capacity(self.holding_cell_htlc_updates.len());
4284                 for htlc_update in self.holding_cell_htlc_updates.drain(..) {
4285                         match htlc_update {
4286                                 HTLCUpdateAwaitingACK::AddHTLC { source, payment_hash, .. } => {
4287                                         dropped_outbound_htlcs.push((source, payment_hash));
4288                                 },
4289                                 _ => {}
4290                         }
4291                 }
4292                 let monitor_update = if let Some(funding_txo) = self.get_funding_txo() {
4293                         // If we haven't yet exchanged funding signatures (ie channel_state < FundingSent),
4294                         // returning a channel monitor update here would imply a channel monitor update before
4295                         // we even registered the channel monitor to begin with, which is invalid.
4296                         // Thus, if we aren't actually at a point where we could conceivably broadcast the
4297                         // funding transaction, don't return a funding txo (which prevents providing the
4298                         // monitor update to the user, even if we return one).
4299                         // See test_duplicate_chan_id and test_pre_lockin_no_chan_closed_update for more.
4300                         if self.channel_state & (ChannelState::FundingSent as u32 | ChannelState::ChannelFunded as u32 | ChannelState::ShutdownComplete as u32) != 0 {
4301                                 self.latest_monitor_update_id += 1;
4302                                 Some((funding_txo, ChannelMonitorUpdate {
4303                                         update_id: self.latest_monitor_update_id,
4304                                         updates: vec![ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast }],
4305                                 }))
4306                         } else { None }
4307                 } else { None };
4308
4309                 self.channel_state = ChannelState::ShutdownComplete as u32;
4310                 self.update_time_counter += 1;
4311                 (monitor_update, dropped_outbound_htlcs)
4312         }
4313 }
4314
4315 fn is_unsupported_shutdown_script(their_features: &InitFeatures, script: &Script) -> bool {
4316         // We restrain shutdown scripts to standards forms to avoid transactions not propagating on the p2p tx-relay network
4317
4318         // BOLT 2 says we must only send a scriptpubkey of certain standard forms,
4319         // which for a a BIP-141-compliant witness program is at max 42 bytes in length.
4320         // So don't let the remote peer feed us some super fee-heavy script.
4321         let is_script_too_long = script.len() > 42;
4322         if is_script_too_long {
4323                 return true;
4324         }
4325
4326         if their_features.supports_shutdown_anysegwit() && script.is_witness_program() && script.as_bytes()[0] != OP_PUSHBYTES_0.into_u8() {
4327                 return false;
4328         }
4329
4330         return !script.is_p2pkh() && !script.is_p2sh() && !script.is_v0_p2wpkh() && !script.is_v0_p2wsh()
4331 }
4332
4333 const SERIALIZATION_VERSION: u8 = 1;
4334 const MIN_SERIALIZATION_VERSION: u8 = 1;
4335
4336 impl Writeable for InboundHTLCRemovalReason {
4337         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
4338                 match self {
4339                         &InboundHTLCRemovalReason::FailRelay(ref error_packet) => {
4340                                 0u8.write(writer)?;
4341                                 error_packet.write(writer)?;
4342                         },
4343                         &InboundHTLCRemovalReason::FailMalformed((ref onion_hash, ref err_code)) => {
4344                                 1u8.write(writer)?;
4345                                 onion_hash.write(writer)?;
4346                                 err_code.write(writer)?;
4347                         },
4348                         &InboundHTLCRemovalReason::Fulfill(ref payment_preimage) => {
4349                                 2u8.write(writer)?;
4350                                 payment_preimage.write(writer)?;
4351                         },
4352                 }
4353                 Ok(())
4354         }
4355 }
4356
4357 impl Readable for InboundHTLCRemovalReason {
4358         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
4359                 Ok(match <u8 as Readable>::read(reader)? {
4360                         0 => InboundHTLCRemovalReason::FailRelay(Readable::read(reader)?),
4361                         1 => InboundHTLCRemovalReason::FailMalformed((Readable::read(reader)?, Readable::read(reader)?)),
4362                         2 => InboundHTLCRemovalReason::Fulfill(Readable::read(reader)?),
4363                         _ => return Err(DecodeError::InvalidValue),
4364                 })
4365         }
4366 }
4367
4368 impl<Signer: Sign> Writeable for Channel<Signer> {
4369         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
4370                 // Note that we write out as if remove_uncommitted_htlcs_and_mark_paused had just been
4371                 // called but include holding cell updates (and obviously we don't modify self).
4372
4373                 writer.write_all(&[SERIALIZATION_VERSION; 1])?;
4374                 writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
4375
4376                 self.user_id.write(writer)?;
4377                 self.config.write(writer)?;
4378
4379                 self.channel_id.write(writer)?;
4380                 (self.channel_state | ChannelState::PeerDisconnected as u32).write(writer)?;
4381                 self.channel_value_satoshis.write(writer)?;
4382
4383                 self.latest_monitor_update_id.write(writer)?;
4384
4385                 let mut key_data = VecWriter(Vec::new());
4386                 self.holder_signer.write(&mut key_data)?;
4387                 assert!(key_data.0.len() < std::usize::MAX);
4388                 assert!(key_data.0.len() < std::u32::MAX as usize);
4389                 (key_data.0.len() as u32).write(writer)?;
4390                 writer.write_all(&key_data.0[..])?;
4391
4392                 self.shutdown_pubkey.write(writer)?;
4393                 self.destination_script.write(writer)?;
4394
4395                 self.cur_holder_commitment_transaction_number.write(writer)?;
4396                 self.cur_counterparty_commitment_transaction_number.write(writer)?;
4397                 self.value_to_self_msat.write(writer)?;
4398
4399                 let mut dropped_inbound_htlcs = 0;
4400                 for htlc in self.pending_inbound_htlcs.iter() {
4401                         if let InboundHTLCState::RemoteAnnounced(_) = htlc.state {
4402                                 dropped_inbound_htlcs += 1;
4403                         }
4404                 }
4405                 (self.pending_inbound_htlcs.len() as u64 - dropped_inbound_htlcs).write(writer)?;
4406                 for htlc in self.pending_inbound_htlcs.iter() {
4407                         if let &InboundHTLCState::RemoteAnnounced(_) = &htlc.state {
4408                                 continue; // Drop
4409                         }
4410                         htlc.htlc_id.write(writer)?;
4411                         htlc.amount_msat.write(writer)?;
4412                         htlc.cltv_expiry.write(writer)?;
4413                         htlc.payment_hash.write(writer)?;
4414                         match &htlc.state {
4415                                 &InboundHTLCState::RemoteAnnounced(_) => unreachable!(),
4416                                 &InboundHTLCState::AwaitingRemoteRevokeToAnnounce(ref htlc_state) => {
4417                                         1u8.write(writer)?;
4418                                         htlc_state.write(writer)?;
4419                                 },
4420                                 &InboundHTLCState::AwaitingAnnouncedRemoteRevoke(ref htlc_state) => {
4421                                         2u8.write(writer)?;
4422                                         htlc_state.write(writer)?;
4423                                 },
4424                                 &InboundHTLCState::Committed => {
4425                                         3u8.write(writer)?;
4426                                 },
4427                                 &InboundHTLCState::LocalRemoved(ref removal_reason) => {
4428                                         4u8.write(writer)?;
4429                                         removal_reason.write(writer)?;
4430                                 },
4431                         }
4432                 }
4433
4434                 (self.pending_outbound_htlcs.len() as u64).write(writer)?;
4435                 for htlc in self.pending_outbound_htlcs.iter() {
4436                         htlc.htlc_id.write(writer)?;
4437                         htlc.amount_msat.write(writer)?;
4438                         htlc.cltv_expiry.write(writer)?;
4439                         htlc.payment_hash.write(writer)?;
4440                         htlc.source.write(writer)?;
4441                         match &htlc.state {
4442                                 &OutboundHTLCState::LocalAnnounced(ref onion_packet) => {
4443                                         0u8.write(writer)?;
4444                                         onion_packet.write(writer)?;
4445                                 },
4446                                 &OutboundHTLCState::Committed => {
4447                                         1u8.write(writer)?;
4448                                 },
4449                                 &OutboundHTLCState::RemoteRemoved(ref fail_reason) => {
4450                                         2u8.write(writer)?;
4451                                         fail_reason.write(writer)?;
4452                                 },
4453                                 &OutboundHTLCState::AwaitingRemoteRevokeToRemove(ref fail_reason) => {
4454                                         3u8.write(writer)?;
4455                                         fail_reason.write(writer)?;
4456                                 },
4457                                 &OutboundHTLCState::AwaitingRemovedRemoteRevoke(ref fail_reason) => {
4458                                         4u8.write(writer)?;
4459                                         fail_reason.write(writer)?;
4460                                 },
4461                         }
4462                 }
4463
4464                 (self.holding_cell_htlc_updates.len() as u64).write(writer)?;
4465                 for update in self.holding_cell_htlc_updates.iter() {
4466                         match update {
4467                                 &HTLCUpdateAwaitingACK::AddHTLC { ref amount_msat, ref cltv_expiry, ref payment_hash, ref source, ref onion_routing_packet } => {
4468                                         0u8.write(writer)?;
4469                                         amount_msat.write(writer)?;
4470                                         cltv_expiry.write(writer)?;
4471                                         payment_hash.write(writer)?;
4472                                         source.write(writer)?;
4473                                         onion_routing_packet.write(writer)?;
4474                                 },
4475                                 &HTLCUpdateAwaitingACK::ClaimHTLC { ref payment_preimage, ref htlc_id } => {
4476                                         1u8.write(writer)?;
4477                                         payment_preimage.write(writer)?;
4478                                         htlc_id.write(writer)?;
4479                                 },
4480                                 &HTLCUpdateAwaitingACK::FailHTLC { ref htlc_id, ref err_packet } => {
4481                                         2u8.write(writer)?;
4482                                         htlc_id.write(writer)?;
4483                                         err_packet.write(writer)?;
4484                                 }
4485                         }
4486                 }
4487
4488                 match self.resend_order {
4489                         RAACommitmentOrder::CommitmentFirst => 0u8.write(writer)?,
4490                         RAACommitmentOrder::RevokeAndACKFirst => 1u8.write(writer)?,
4491                 }
4492
4493                 self.monitor_pending_funding_locked.write(writer)?;
4494                 self.monitor_pending_revoke_and_ack.write(writer)?;
4495                 self.monitor_pending_commitment_signed.write(writer)?;
4496
4497                 (self.monitor_pending_forwards.len() as u64).write(writer)?;
4498                 for &(ref pending_forward, ref htlc_id) in self.monitor_pending_forwards.iter() {
4499                         pending_forward.write(writer)?;
4500                         htlc_id.write(writer)?;
4501                 }
4502
4503                 (self.monitor_pending_failures.len() as u64).write(writer)?;
4504                 for &(ref htlc_source, ref payment_hash, ref fail_reason) in self.monitor_pending_failures.iter() {
4505                         htlc_source.write(writer)?;
4506                         payment_hash.write(writer)?;
4507                         fail_reason.write(writer)?;
4508                 }
4509
4510                 self.pending_update_fee.write(writer)?;
4511                 self.holding_cell_update_fee.write(writer)?;
4512
4513                 self.next_holder_htlc_id.write(writer)?;
4514                 (self.next_counterparty_htlc_id - dropped_inbound_htlcs).write(writer)?;
4515                 self.update_time_counter.write(writer)?;
4516                 self.feerate_per_kw.write(writer)?;
4517
4518                 match self.last_sent_closing_fee {
4519                         Some((feerate, fee, sig)) => {
4520                                 1u8.write(writer)?;
4521                                 feerate.write(writer)?;
4522                                 fee.write(writer)?;
4523                                 sig.write(writer)?;
4524                         },
4525                         None => 0u8.write(writer)?,
4526                 }
4527
4528                 self.funding_tx_confirmed_in.write(writer)?;
4529                 self.funding_tx_confirmation_height.write(writer)?;
4530                 self.short_channel_id.write(writer)?;
4531
4532                 self.counterparty_dust_limit_satoshis.write(writer)?;
4533                 self.holder_dust_limit_satoshis.write(writer)?;
4534                 self.counterparty_max_htlc_value_in_flight_msat.write(writer)?;
4535                 self.counterparty_selected_channel_reserve_satoshis.write(writer)?;
4536                 self.counterparty_htlc_minimum_msat.write(writer)?;
4537                 self.holder_htlc_minimum_msat.write(writer)?;
4538                 self.counterparty_max_accepted_htlcs.write(writer)?;
4539                 self.minimum_depth.write(writer)?;
4540
4541                 match &self.counterparty_forwarding_info {
4542                         Some(info) => {
4543                                 1u8.write(writer)?;
4544                                 info.fee_base_msat.write(writer)?;
4545                                 info.fee_proportional_millionths.write(writer)?;
4546                                 info.cltv_expiry_delta.write(writer)?;
4547                         },
4548                         None => 0u8.write(writer)?
4549                 }
4550
4551                 self.channel_transaction_parameters.write(writer)?;
4552                 self.funding_transaction.write(writer)?;
4553
4554                 self.counterparty_cur_commitment_point.write(writer)?;
4555                 self.counterparty_prev_commitment_point.write(writer)?;
4556                 self.counterparty_node_id.write(writer)?;
4557
4558                 self.counterparty_shutdown_scriptpubkey.write(writer)?;
4559
4560                 self.commitment_secrets.write(writer)?;
4561                 Ok(())
4562         }
4563 }
4564
4565 const MAX_ALLOC_SIZE: usize = 64*1024;
4566 impl<'a, Signer: Sign, K: Deref> ReadableArgs<&'a K> for Channel<Signer>
4567                 where K::Target: KeysInterface<Signer = Signer> {
4568         fn read<R : ::std::io::Read>(reader: &mut R, keys_source: &'a K) -> Result<Self, DecodeError> {
4569                 let _ver: u8 = Readable::read(reader)?;
4570                 let min_ver: u8 = Readable::read(reader)?;
4571                 if min_ver > SERIALIZATION_VERSION {
4572                         return Err(DecodeError::UnknownVersion);
4573                 }
4574
4575                 let user_id = Readable::read(reader)?;
4576                 let config: ChannelConfig = Readable::read(reader)?;
4577
4578                 let channel_id = Readable::read(reader)?;
4579                 let channel_state = Readable::read(reader)?;
4580                 let channel_value_satoshis = Readable::read(reader)?;
4581
4582                 let latest_monitor_update_id = Readable::read(reader)?;
4583
4584                 let keys_len: u32 = Readable::read(reader)?;
4585                 let mut keys_data = Vec::with_capacity(cmp::min(keys_len as usize, MAX_ALLOC_SIZE));
4586                 while keys_data.len() != keys_len as usize {
4587                         // Read 1KB at a time to avoid accidentally allocating 4GB on corrupted channel keys
4588                         let mut data = [0; 1024];
4589                         let read_slice = &mut data[0..cmp::min(1024, keys_len as usize - keys_data.len())];
4590                         reader.read_exact(read_slice)?;
4591                         keys_data.extend_from_slice(read_slice);
4592                 }
4593                 let holder_signer = keys_source.read_chan_signer(&keys_data)?;
4594
4595                 let shutdown_pubkey = Readable::read(reader)?;
4596                 let destination_script = Readable::read(reader)?;
4597
4598                 let cur_holder_commitment_transaction_number = Readable::read(reader)?;
4599                 let cur_counterparty_commitment_transaction_number = Readable::read(reader)?;
4600                 let value_to_self_msat = Readable::read(reader)?;
4601
4602                 let pending_inbound_htlc_count: u64 = Readable::read(reader)?;
4603                 let mut pending_inbound_htlcs = Vec::with_capacity(cmp::min(pending_inbound_htlc_count as usize, OUR_MAX_HTLCS as usize));
4604                 for _ in 0..pending_inbound_htlc_count {
4605                         pending_inbound_htlcs.push(InboundHTLCOutput {
4606                                 htlc_id: Readable::read(reader)?,
4607                                 amount_msat: Readable::read(reader)?,
4608                                 cltv_expiry: Readable::read(reader)?,
4609                                 payment_hash: Readable::read(reader)?,
4610                                 state: match <u8 as Readable>::read(reader)? {
4611                                         1 => InboundHTLCState::AwaitingRemoteRevokeToAnnounce(Readable::read(reader)?),
4612                                         2 => InboundHTLCState::AwaitingAnnouncedRemoteRevoke(Readable::read(reader)?),
4613                                         3 => InboundHTLCState::Committed,
4614                                         4 => InboundHTLCState::LocalRemoved(Readable::read(reader)?),
4615                                         _ => return Err(DecodeError::InvalidValue),
4616                                 },
4617                         });
4618                 }
4619
4620                 let pending_outbound_htlc_count: u64 = Readable::read(reader)?;
4621                 let mut pending_outbound_htlcs = Vec::with_capacity(cmp::min(pending_outbound_htlc_count as usize, OUR_MAX_HTLCS as usize));
4622                 for _ in 0..pending_outbound_htlc_count {
4623                         pending_outbound_htlcs.push(OutboundHTLCOutput {
4624                                 htlc_id: Readable::read(reader)?,
4625                                 amount_msat: Readable::read(reader)?,
4626                                 cltv_expiry: Readable::read(reader)?,
4627                                 payment_hash: Readable::read(reader)?,
4628                                 source: Readable::read(reader)?,
4629                                 state: match <u8 as Readable>::read(reader)? {
4630                                         0 => OutboundHTLCState::LocalAnnounced(Box::new(Readable::read(reader)?)),
4631                                         1 => OutboundHTLCState::Committed,
4632                                         2 => OutboundHTLCState::RemoteRemoved(Readable::read(reader)?),
4633                                         3 => OutboundHTLCState::AwaitingRemoteRevokeToRemove(Readable::read(reader)?),
4634                                         4 => OutboundHTLCState::AwaitingRemovedRemoteRevoke(Readable::read(reader)?),
4635                                         _ => return Err(DecodeError::InvalidValue),
4636                                 },
4637                         });
4638                 }
4639
4640                 let holding_cell_htlc_update_count: u64 = Readable::read(reader)?;
4641                 let mut holding_cell_htlc_updates = Vec::with_capacity(cmp::min(holding_cell_htlc_update_count as usize, OUR_MAX_HTLCS as usize*2));
4642                 for _ in 0..holding_cell_htlc_update_count {
4643                         holding_cell_htlc_updates.push(match <u8 as Readable>::read(reader)? {
4644                                 0 => HTLCUpdateAwaitingACK::AddHTLC {
4645                                         amount_msat: Readable::read(reader)?,
4646                                         cltv_expiry: Readable::read(reader)?,
4647                                         payment_hash: Readable::read(reader)?,
4648                                         source: Readable::read(reader)?,
4649                                         onion_routing_packet: Readable::read(reader)?,
4650                                 },
4651                                 1 => HTLCUpdateAwaitingACK::ClaimHTLC {
4652                                         payment_preimage: Readable::read(reader)?,
4653                                         htlc_id: Readable::read(reader)?,
4654                                 },
4655                                 2 => HTLCUpdateAwaitingACK::FailHTLC {
4656                                         htlc_id: Readable::read(reader)?,
4657                                         err_packet: Readable::read(reader)?,
4658                                 },
4659                                 _ => return Err(DecodeError::InvalidValue),
4660                         });
4661                 }
4662
4663                 let resend_order = match <u8 as Readable>::read(reader)? {
4664                         0 => RAACommitmentOrder::CommitmentFirst,
4665                         1 => RAACommitmentOrder::RevokeAndACKFirst,
4666                         _ => return Err(DecodeError::InvalidValue),
4667                 };
4668
4669                 let monitor_pending_funding_locked = Readable::read(reader)?;
4670                 let monitor_pending_revoke_and_ack = Readable::read(reader)?;
4671                 let monitor_pending_commitment_signed = Readable::read(reader)?;
4672
4673                 let monitor_pending_forwards_count: u64 = Readable::read(reader)?;
4674                 let mut monitor_pending_forwards = Vec::with_capacity(cmp::min(monitor_pending_forwards_count as usize, OUR_MAX_HTLCS as usize));
4675                 for _ in 0..monitor_pending_forwards_count {
4676                         monitor_pending_forwards.push((Readable::read(reader)?, Readable::read(reader)?));
4677                 }
4678
4679                 let monitor_pending_failures_count: u64 = Readable::read(reader)?;
4680                 let mut monitor_pending_failures = Vec::with_capacity(cmp::min(monitor_pending_failures_count as usize, OUR_MAX_HTLCS as usize));
4681                 for _ in 0..monitor_pending_failures_count {
4682                         monitor_pending_failures.push((Readable::read(reader)?, Readable::read(reader)?, Readable::read(reader)?));
4683                 }
4684
4685                 let pending_update_fee = Readable::read(reader)?;
4686                 let holding_cell_update_fee = Readable::read(reader)?;
4687
4688                 let next_holder_htlc_id = Readable::read(reader)?;
4689                 let next_counterparty_htlc_id = Readable::read(reader)?;
4690                 let update_time_counter = Readable::read(reader)?;
4691                 let feerate_per_kw = Readable::read(reader)?;
4692
4693                 let last_sent_closing_fee = match <u8 as Readable>::read(reader)? {
4694                         0 => None,
4695                         1 => Some((Readable::read(reader)?, Readable::read(reader)?, Readable::read(reader)?)),
4696                         _ => return Err(DecodeError::InvalidValue),
4697                 };
4698
4699                 let funding_tx_confirmed_in = Readable::read(reader)?;
4700                 let funding_tx_confirmation_height = Readable::read(reader)?;
4701                 let short_channel_id = Readable::read(reader)?;
4702
4703                 let counterparty_dust_limit_satoshis = Readable::read(reader)?;
4704                 let holder_dust_limit_satoshis = Readable::read(reader)?;
4705                 let counterparty_max_htlc_value_in_flight_msat = Readable::read(reader)?;
4706                 let counterparty_selected_channel_reserve_satoshis = Readable::read(reader)?;
4707                 let counterparty_htlc_minimum_msat = Readable::read(reader)?;
4708                 let holder_htlc_minimum_msat = Readable::read(reader)?;
4709                 let counterparty_max_accepted_htlcs = Readable::read(reader)?;
4710                 let minimum_depth = Readable::read(reader)?;
4711
4712                 let counterparty_forwarding_info = match <u8 as Readable>::read(reader)? {
4713                         0 => None,
4714                         1 => Some(CounterpartyForwardingInfo {
4715                                 fee_base_msat: Readable::read(reader)?,
4716                                 fee_proportional_millionths: Readable::read(reader)?,
4717                                 cltv_expiry_delta: Readable::read(reader)?,
4718                         }),
4719                         _ => return Err(DecodeError::InvalidValue),
4720                 };
4721
4722                 let channel_parameters = Readable::read(reader)?;
4723                 let funding_transaction = Readable::read(reader)?;
4724
4725                 let counterparty_cur_commitment_point = Readable::read(reader)?;
4726
4727                 let counterparty_prev_commitment_point = Readable::read(reader)?;
4728                 let counterparty_node_id = Readable::read(reader)?;
4729
4730                 let counterparty_shutdown_scriptpubkey = Readable::read(reader)?;
4731                 let commitment_secrets = Readable::read(reader)?;
4732
4733                 let mut secp_ctx = Secp256k1::new();
4734                 secp_ctx.seeded_randomize(&keys_source.get_secure_random_bytes());
4735
4736                 Ok(Channel {
4737                         user_id,
4738
4739                         config,
4740                         channel_id,
4741                         channel_state,
4742                         secp_ctx,
4743                         channel_value_satoshis,
4744
4745                         latest_monitor_update_id,
4746
4747                         holder_signer,
4748                         shutdown_pubkey,
4749                         destination_script,
4750
4751                         cur_holder_commitment_transaction_number,
4752                         cur_counterparty_commitment_transaction_number,
4753                         value_to_self_msat,
4754
4755                         pending_inbound_htlcs,
4756                         pending_outbound_htlcs,
4757                         holding_cell_htlc_updates,
4758
4759                         resend_order,
4760
4761                         monitor_pending_funding_locked,
4762                         monitor_pending_revoke_and_ack,
4763                         monitor_pending_commitment_signed,
4764                         monitor_pending_forwards,
4765                         monitor_pending_failures,
4766
4767                         pending_update_fee,
4768                         holding_cell_update_fee,
4769                         next_holder_htlc_id,
4770                         next_counterparty_htlc_id,
4771                         update_time_counter,
4772                         feerate_per_kw,
4773
4774                         #[cfg(debug_assertions)]
4775                         holder_max_commitment_tx_output: ::std::sync::Mutex::new((0, 0)),
4776                         #[cfg(debug_assertions)]
4777                         counterparty_max_commitment_tx_output: ::std::sync::Mutex::new((0, 0)),
4778
4779                         last_sent_closing_fee,
4780
4781                         funding_tx_confirmed_in,
4782                         funding_tx_confirmation_height,
4783                         short_channel_id,
4784
4785                         counterparty_dust_limit_satoshis,
4786                         holder_dust_limit_satoshis,
4787                         counterparty_max_htlc_value_in_flight_msat,
4788                         counterparty_selected_channel_reserve_satoshis,
4789                         counterparty_htlc_minimum_msat,
4790                         holder_htlc_minimum_msat,
4791                         counterparty_max_accepted_htlcs,
4792                         minimum_depth,
4793
4794                         counterparty_forwarding_info,
4795
4796                         channel_transaction_parameters: channel_parameters,
4797                         funding_transaction,
4798
4799                         counterparty_cur_commitment_point,
4800                         counterparty_prev_commitment_point,
4801                         counterparty_node_id,
4802
4803                         counterparty_shutdown_scriptpubkey,
4804
4805                         commitment_secrets,
4806
4807                         network_sync: UpdateStatus::Fresh,
4808
4809                         #[cfg(any(test, feature = "fuzztarget"))]
4810                         next_local_commitment_tx_fee_info_cached: Mutex::new(None),
4811                         #[cfg(any(test, feature = "fuzztarget"))]
4812                         next_remote_commitment_tx_fee_info_cached: Mutex::new(None),
4813                 })
4814         }
4815 }
4816
4817 #[cfg(test)]
4818 mod tests {
4819         use bitcoin::util::bip143;
4820         use bitcoin::consensus::encode::serialize;
4821         use bitcoin::blockdata::script::{Script, Builder};
4822         use bitcoin::blockdata::transaction::{Transaction, TxOut, SigHashType};
4823         use bitcoin::blockdata::constants::genesis_block;
4824         use bitcoin::blockdata::opcodes;
4825         use bitcoin::network::constants::Network;
4826         use bitcoin::hashes::hex::FromHex;
4827         use hex;
4828         use ln::{PaymentPreimage, PaymentHash};
4829         use ln::channelmanager::{BestBlock, HTLCSource};
4830         use ln::channel::{Channel,InboundHTLCOutput,OutboundHTLCOutput,InboundHTLCState,OutboundHTLCState,HTLCOutputInCommitment,HTLCCandidate,HTLCInitiator,TxCreationKeys};
4831         use ln::channel::MAX_FUNDING_SATOSHIS;
4832         use ln::features::InitFeatures;
4833         use ln::msgs::{ChannelUpdate, DataLossProtect, DecodeError, OptionalField, UnsignedChannelUpdate};
4834         use ln::chan_utils;
4835         use ln::chan_utils::{ChannelPublicKeys, HolderCommitmentTransaction, CounterpartyChannelTransactionParameters, HTLC_SUCCESS_TX_WEIGHT, HTLC_TIMEOUT_TX_WEIGHT};
4836         use chain::chaininterface::{FeeEstimator,ConfirmationTarget};
4837         use chain::keysinterface::{InMemorySigner, KeysInterface, BaseSign};
4838         use chain::transaction::OutPoint;
4839         use util::config::UserConfig;
4840         use util::enforcing_trait_impls::EnforcingSigner;
4841         use util::test_utils;
4842         use util::logger::Logger;
4843         use bitcoin::secp256k1::{Secp256k1, Message, Signature, All};
4844         use bitcoin::secp256k1::ffi::Signature as FFISignature;
4845         use bitcoin::secp256k1::key::{SecretKey,PublicKey};
4846         use bitcoin::secp256k1::recovery::RecoverableSignature;
4847         use bitcoin::hashes::sha256::Hash as Sha256;
4848         use bitcoin::hashes::Hash;
4849         use bitcoin::hash_types::{Txid, WPubkeyHash};
4850         use std::sync::Arc;
4851
4852         struct TestFeeEstimator {
4853                 fee_est: u32
4854         }
4855         impl FeeEstimator for TestFeeEstimator {
4856                 fn get_est_sat_per_1000_weight(&self, _: ConfirmationTarget) -> u32 {
4857                         self.fee_est
4858                 }
4859         }
4860
4861         #[test]
4862         fn test_max_funding_satoshis() {
4863                 assert!(MAX_FUNDING_SATOSHIS <= 21_000_000 * 100_000_000,
4864                         "MAX_FUNDING_SATOSHIS is greater than all satoshis in existence");
4865         }
4866
4867         struct Keys {
4868                 signer: InMemorySigner,
4869         }
4870         impl KeysInterface for Keys {
4871                 type Signer = InMemorySigner;
4872
4873                 fn get_node_secret(&self) -> SecretKey { panic!(); }
4874                 fn get_destination_script(&self) -> Script {
4875                         let secp_ctx = Secp256k1::signing_only();
4876                         let channel_monitor_claim_key = SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap();
4877                         let channel_monitor_claim_key_hash = WPubkeyHash::hash(&PublicKey::from_secret_key(&secp_ctx, &channel_monitor_claim_key).serialize());
4878                         Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&channel_monitor_claim_key_hash[..]).into_script()
4879                 }
4880
4881                 fn get_shutdown_pubkey(&self) -> PublicKey {
4882                         let secp_ctx = Secp256k1::signing_only();
4883                         let channel_close_key = SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap();
4884                         PublicKey::from_secret_key(&secp_ctx, &channel_close_key)
4885                 }
4886
4887                 fn get_channel_signer(&self, _inbound: bool, _channel_value_satoshis: u64) -> InMemorySigner {
4888                         self.signer.clone()
4889                 }
4890                 fn get_secure_random_bytes(&self) -> [u8; 32] { [0; 32] }
4891                 fn read_chan_signer(&self, _data: &[u8]) -> Result<Self::Signer, DecodeError> { panic!(); }
4892                 fn sign_invoice(&self, _invoice_preimage: Vec<u8>) -> Result<RecoverableSignature, ()> { panic!(); }
4893         }
4894
4895         fn public_from_secret_hex(secp_ctx: &Secp256k1<All>, hex: &str) -> PublicKey {
4896                 PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode(hex).unwrap()[..]).unwrap())
4897         }
4898
4899         // Check that, during channel creation, we use the same feerate in the open channel message
4900         // as we do in the Channel object creation itself.
4901         #[test]
4902         fn test_open_channel_msg_fee() {
4903                 let original_fee = 253;
4904                 let mut fee_est = TestFeeEstimator{fee_est: original_fee };
4905                 let secp_ctx = Secp256k1::new();
4906                 let seed = [42; 32];
4907                 let network = Network::Testnet;
4908                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
4909
4910                 let node_a_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
4911                 let config = UserConfig::default();
4912                 let node_a_chan = Channel::<EnforcingSigner>::new_outbound(&&fee_est, &&keys_provider, node_a_node_id, 10000000, 100000, 42, &config).unwrap();
4913
4914                 // Now change the fee so we can check that the fee in the open_channel message is the
4915                 // same as the old fee.
4916                 fee_est.fee_est = 500;
4917                 let open_channel_msg = node_a_chan.get_open_channel(genesis_block(network).header.block_hash());
4918                 assert_eq!(open_channel_msg.feerate_per_kw, original_fee);
4919         }
4920
4921         #[test]
4922         fn test_holder_vs_counterparty_dust_limit() {
4923                 // Test that when calculating the local and remote commitment transaction fees, the correct
4924                 // dust limits are used.
4925                 let feeest = TestFeeEstimator{fee_est: 15000};
4926                 let secp_ctx = Secp256k1::new();
4927                 let seed = [42; 32];
4928                 let network = Network::Testnet;
4929                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
4930
4931                 // Go through the flow of opening a channel between two nodes, making sure
4932                 // they have different dust limits.
4933
4934                 // Create Node A's channel pointing to Node B's pubkey
4935                 let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
4936                 let config = UserConfig::default();
4937                 let mut node_a_chan = Channel::<EnforcingSigner>::new_outbound(&&feeest, &&keys_provider, node_b_node_id, 10000000, 100000, 42, &config).unwrap();
4938
4939                 // Create Node B's channel by receiving Node A's open_channel message
4940                 // Make sure A's dust limit is as we expect.
4941                 let open_channel_msg = node_a_chan.get_open_channel(genesis_block(network).header.block_hash());
4942                 assert_eq!(open_channel_msg.dust_limit_satoshis, 1560);
4943                 let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[7; 32]).unwrap());
4944                 let node_b_chan = Channel::<EnforcingSigner>::new_from_req(&&feeest, &&keys_provider, node_b_node_id, InitFeatures::known(), &open_channel_msg, 7, &config).unwrap();
4945
4946                 // Node B --> Node A: accept channel, explicitly setting B's dust limit.
4947                 let mut accept_channel_msg = node_b_chan.get_accept_channel();
4948                 accept_channel_msg.dust_limit_satoshis = 546;
4949                 node_a_chan.accept_channel(&accept_channel_msg, &config, InitFeatures::known()).unwrap();
4950
4951                 // Put some inbound and outbound HTLCs in A's channel.
4952                 let htlc_amount_msat = 11_092_000; // put an amount below A's effective dust limit but above B's.
4953                 node_a_chan.pending_inbound_htlcs.push(InboundHTLCOutput {
4954                         htlc_id: 0,
4955                         amount_msat: htlc_amount_msat,
4956                         payment_hash: PaymentHash(Sha256::hash(&[42; 32]).into_inner()),
4957                         cltv_expiry: 300000000,
4958                         state: InboundHTLCState::Committed,
4959                 });
4960
4961                 node_a_chan.pending_outbound_htlcs.push(OutboundHTLCOutput {
4962                         htlc_id: 1,
4963                         amount_msat: htlc_amount_msat, // put an amount below A's dust amount but above B's.
4964                         payment_hash: PaymentHash(Sha256::hash(&[43; 32]).into_inner()),
4965                         cltv_expiry: 200000000,
4966                         state: OutboundHTLCState::Committed,
4967                         source: HTLCSource::OutboundRoute {
4968                                 path: Vec::new(),
4969                                 session_priv: SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap(),
4970                                 first_hop_htlc_msat: 548,
4971                         }
4972                 });
4973
4974                 // Make sure when Node A calculates their local commitment transaction, none of the HTLCs pass
4975                 // the dust limit check.
4976                 let htlc_candidate = HTLCCandidate::new(htlc_amount_msat, HTLCInitiator::LocalOffered);
4977                 let local_commit_tx_fee = node_a_chan.next_local_commit_tx_fee_msat(htlc_candidate, None);
4978                 let local_commit_fee_0_htlcs = node_a_chan.commit_tx_fee_msat(0);
4979                 assert_eq!(local_commit_tx_fee, local_commit_fee_0_htlcs);
4980
4981                 // Finally, make sure that when Node A calculates the remote's commitment transaction fees, all
4982                 // of the HTLCs are seen to be above the dust limit.
4983                 node_a_chan.channel_transaction_parameters.is_outbound_from_holder = false;
4984                 let remote_commit_fee_3_htlcs = node_a_chan.commit_tx_fee_msat(3);
4985                 let htlc_candidate = HTLCCandidate::new(htlc_amount_msat, HTLCInitiator::LocalOffered);
4986                 let remote_commit_tx_fee = node_a_chan.next_remote_commit_tx_fee_msat(htlc_candidate, None);
4987                 assert_eq!(remote_commit_tx_fee, remote_commit_fee_3_htlcs);
4988         }
4989
4990         #[test]
4991         fn test_timeout_vs_success_htlc_dust_limit() {
4992                 // Make sure that when `next_remote_commit_tx_fee_msat` and `next_local_commit_tx_fee_msat`
4993                 // calculate the real dust limits for HTLCs (i.e. the dust limit given by the counterparty
4994                 // *plus* the fees paid for the HTLC) they don't swap `HTLC_SUCCESS_TX_WEIGHT` for
4995                 // `HTLC_TIMEOUT_TX_WEIGHT`, and vice versa.
4996                 let fee_est = TestFeeEstimator{fee_est: 253 };
4997                 let secp_ctx = Secp256k1::new();
4998                 let seed = [42; 32];
4999                 let network = Network::Testnet;
5000                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
5001
5002                 let node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
5003                 let config = UserConfig::default();
5004                 let mut chan = Channel::<EnforcingSigner>::new_outbound(&&fee_est, &&keys_provider, node_id, 10000000, 100000, 42, &config).unwrap();
5005
5006                 let commitment_tx_fee_0_htlcs = chan.commit_tx_fee_msat(0);
5007                 let commitment_tx_fee_1_htlc = chan.commit_tx_fee_msat(1);
5008
5009                 // If HTLC_SUCCESS_TX_WEIGHT and HTLC_TIMEOUT_TX_WEIGHT were swapped: then this HTLC would be
5010                 // counted as dust when it shouldn't be.
5011                 let htlc_amt_above_timeout = ((253 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + chan.holder_dust_limit_satoshis + 1) * 1000;
5012                 let htlc_candidate = HTLCCandidate::new(htlc_amt_above_timeout, HTLCInitiator::LocalOffered);
5013                 let commitment_tx_fee = chan.next_local_commit_tx_fee_msat(htlc_candidate, None);
5014                 assert_eq!(commitment_tx_fee, commitment_tx_fee_1_htlc);
5015
5016                 // If swapped: this HTLC would be counted as non-dust when it shouldn't be.
5017                 let dust_htlc_amt_below_success = ((253 * HTLC_SUCCESS_TX_WEIGHT / 1000) + chan.holder_dust_limit_satoshis - 1) * 1000;
5018                 let htlc_candidate = HTLCCandidate::new(dust_htlc_amt_below_success, HTLCInitiator::RemoteOffered);
5019                 let commitment_tx_fee = chan.next_local_commit_tx_fee_msat(htlc_candidate, None);
5020                 assert_eq!(commitment_tx_fee, commitment_tx_fee_0_htlcs);
5021
5022                 chan.channel_transaction_parameters.is_outbound_from_holder = false;
5023
5024                 // If swapped: this HTLC would be counted as non-dust when it shouldn't be.
5025                 let dust_htlc_amt_above_timeout = ((253 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + chan.counterparty_dust_limit_satoshis + 1) * 1000;
5026                 let htlc_candidate = HTLCCandidate::new(dust_htlc_amt_above_timeout, HTLCInitiator::LocalOffered);
5027                 let commitment_tx_fee = chan.next_remote_commit_tx_fee_msat(htlc_candidate, None);
5028                 assert_eq!(commitment_tx_fee, commitment_tx_fee_0_htlcs);
5029
5030                 // If swapped: this HTLC would be counted as dust when it shouldn't be.
5031                 let htlc_amt_below_success = ((253 * HTLC_SUCCESS_TX_WEIGHT / 1000) + chan.counterparty_dust_limit_satoshis - 1) * 1000;
5032                 let htlc_candidate = HTLCCandidate::new(htlc_amt_below_success, HTLCInitiator::RemoteOffered);
5033                 let commitment_tx_fee = chan.next_remote_commit_tx_fee_msat(htlc_candidate, None);
5034                 assert_eq!(commitment_tx_fee, commitment_tx_fee_1_htlc);
5035         }
5036
5037         #[test]
5038         fn channel_reestablish_no_updates() {
5039                 let feeest = TestFeeEstimator{fee_est: 15000};
5040                 let logger = test_utils::TestLogger::new();
5041                 let secp_ctx = Secp256k1::new();
5042                 let seed = [42; 32];
5043                 let network = Network::Testnet;
5044                 let best_block = BestBlock::from_genesis(network);
5045                 let chain_hash = best_block.block_hash();
5046                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
5047
5048                 // Go through the flow of opening a channel between two nodes.
5049
5050                 // Create Node A's channel pointing to Node B's pubkey
5051                 let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
5052                 let config = UserConfig::default();
5053                 let mut node_a_chan = Channel::<EnforcingSigner>::new_outbound(&&feeest, &&keys_provider, node_b_node_id, 10000000, 100000, 42, &config).unwrap();
5054
5055                 // Create Node B's channel by receiving Node A's open_channel message
5056                 let open_channel_msg = node_a_chan.get_open_channel(chain_hash);
5057                 let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[7; 32]).unwrap());
5058                 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();
5059
5060                 // Node B --> Node A: accept channel
5061                 let accept_channel_msg = node_b_chan.get_accept_channel();
5062                 node_a_chan.accept_channel(&accept_channel_msg, &config, InitFeatures::known()).unwrap();
5063
5064                 // Node A --> Node B: funding created
5065                 let output_script = node_a_chan.get_funding_redeemscript();
5066                 let tx = Transaction { version: 1, lock_time: 0, input: Vec::new(), output: vec![TxOut {
5067                         value: 10000000, script_pubkey: output_script.clone(),
5068                 }]};
5069                 let funding_outpoint = OutPoint{ txid: tx.txid(), index: 0 };
5070                 let funding_created_msg = node_a_chan.get_outbound_funding_created(tx.clone(), funding_outpoint, &&logger).unwrap();
5071                 let (funding_signed_msg, _) = node_b_chan.funding_created(&funding_created_msg, best_block, &&logger).unwrap();
5072
5073                 // Node B --> Node A: funding signed
5074                 let _ = node_a_chan.funding_signed(&funding_signed_msg, best_block, &&logger);
5075
5076                 // Now disconnect the two nodes and check that the commitment point in
5077                 // Node B's channel_reestablish message is sane.
5078                 node_b_chan.remove_uncommitted_htlcs_and_mark_paused(&&logger);
5079                 let msg = node_b_chan.get_channel_reestablish(&&logger);
5080                 assert_eq!(msg.next_local_commitment_number, 1); // now called next_commitment_number
5081                 assert_eq!(msg.next_remote_commitment_number, 0); // now called next_revocation_number
5082                 match msg.data_loss_protect {
5083                         OptionalField::Present(DataLossProtect { your_last_per_commitment_secret, .. }) => {
5084                                 assert_eq!(your_last_per_commitment_secret, [0; 32]);
5085                         },
5086                         _ => panic!()
5087                 }
5088
5089                 // Check that the commitment point in Node A's channel_reestablish message
5090                 // is sane.
5091                 node_a_chan.remove_uncommitted_htlcs_and_mark_paused(&&logger);
5092                 let msg = node_a_chan.get_channel_reestablish(&&logger);
5093                 assert_eq!(msg.next_local_commitment_number, 1); // now called next_commitment_number
5094                 assert_eq!(msg.next_remote_commitment_number, 0); // now called next_revocation_number
5095                 match msg.data_loss_protect {
5096                         OptionalField::Present(DataLossProtect { your_last_per_commitment_secret, .. }) => {
5097                                 assert_eq!(your_last_per_commitment_secret, [0; 32]);
5098                         },
5099                         _ => panic!()
5100                 }
5101         }
5102
5103         #[test]
5104         fn channel_update() {
5105                 let feeest = TestFeeEstimator{fee_est: 15000};
5106                 let secp_ctx = Secp256k1::new();
5107                 let seed = [42; 32];
5108                 let network = Network::Testnet;
5109                 let chain_hash = genesis_block(network).header.block_hash();
5110                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
5111
5112                 // Create a channel.
5113                 let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
5114                 let config = UserConfig::default();
5115                 let mut node_a_chan = Channel::<EnforcingSigner>::new_outbound(&&feeest, &&keys_provider, node_b_node_id, 10000000, 100000, 42, &config).unwrap();
5116                 assert!(node_a_chan.counterparty_forwarding_info.is_none());
5117                 assert_eq!(node_a_chan.holder_htlc_minimum_msat, 1); // the default
5118                 assert!(node_a_chan.counterparty_forwarding_info().is_none());
5119
5120                 // Make sure that receiving a channel update will update the Channel as expected.
5121                 let update = ChannelUpdate {
5122                         contents: UnsignedChannelUpdate {
5123                                 chain_hash,
5124                                 short_channel_id: 0,
5125                                 timestamp: 0,
5126                                 flags: 0,
5127                                 cltv_expiry_delta: 100,
5128                                 htlc_minimum_msat: 5,
5129                                 htlc_maximum_msat: OptionalField::Absent,
5130                                 fee_base_msat: 110,
5131                                 fee_proportional_millionths: 11,
5132                                 excess_data: Vec::new(),
5133                         },
5134                         signature: Signature::from(unsafe { FFISignature::new() })
5135                 };
5136                 node_a_chan.channel_update(&update).unwrap();
5137
5138                 // The counterparty can send an update with a higher minimum HTLC, but that shouldn't
5139                 // change our official htlc_minimum_msat.
5140                 assert_eq!(node_a_chan.holder_htlc_minimum_msat, 1);
5141                 match node_a_chan.counterparty_forwarding_info() {
5142                         Some(info) => {
5143                                 assert_eq!(info.cltv_expiry_delta, 100);
5144                                 assert_eq!(info.fee_base_msat, 110);
5145                                 assert_eq!(info.fee_proportional_millionths, 11);
5146                         },
5147                         None => panic!("expected counterparty forwarding info to be Some")
5148                 }
5149         }
5150
5151         #[test]
5152         fn outbound_commitment_test() {
5153                 // Test vectors from BOLT 3 Appendix C:
5154                 let feeest = TestFeeEstimator{fee_est: 15000};
5155                 let logger : Arc<Logger> = Arc::new(test_utils::TestLogger::new());
5156                 let secp_ctx = Secp256k1::new();
5157
5158                 let mut signer = InMemorySigner::new(
5159                         &secp_ctx,
5160                         SecretKey::from_slice(&hex::decode("30ff4956bbdd3222d44cc5e8a1261dab1e07957bdac5ae88fe3261ef321f3749").unwrap()[..]).unwrap(),
5161                         SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap(),
5162                         SecretKey::from_slice(&hex::decode("1111111111111111111111111111111111111111111111111111111111111111").unwrap()[..]).unwrap(),
5163                         SecretKey::from_slice(&hex::decode("3333333333333333333333333333333333333333333333333333333333333333").unwrap()[..]).unwrap(),
5164                         SecretKey::from_slice(&hex::decode("1111111111111111111111111111111111111111111111111111111111111111").unwrap()[..]).unwrap(),
5165
5166                         // These aren't set in the test vectors:
5167                         [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],
5168                         10_000_000,
5169                         [0; 32]
5170                 );
5171
5172                 assert_eq!(signer.pubkeys().funding_pubkey.serialize()[..],
5173                                 hex::decode("023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb").unwrap()[..]);
5174                 let keys_provider = Keys { signer: signer.clone() };
5175
5176                 let counterparty_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
5177                 let mut config = UserConfig::default();
5178                 config.channel_options.announced_channel = false;
5179                 let mut chan = Channel::<InMemorySigner>::new_outbound(&&feeest, &&keys_provider, counterparty_node_id, 10_000_000, 100000, 42, &config).unwrap(); // Nothing uses their network key in this test
5180                 chan.holder_dust_limit_satoshis = 546;
5181
5182                 let funding_info = OutPoint{ txid: Txid::from_hex("8984484a580b825b9972d7adb15050b3ab624ccd731946b3eeddb92f4e7ef6be").unwrap(), index: 0 };
5183
5184                 let counterparty_pubkeys = ChannelPublicKeys {
5185                         funding_pubkey: public_from_secret_hex(&secp_ctx, "1552dfba4f6cf29a62a0af13c8d6981d36d0ef8d61ba10fb0fe90da7634d7e13"),
5186                         revocation_basepoint: PublicKey::from_slice(&hex::decode("02466d7fcae563e5cb09a0d1870bb580344804617879a14949cf22285f1bae3f27").unwrap()[..]).unwrap(),
5187                         payment_point: public_from_secret_hex(&secp_ctx, "4444444444444444444444444444444444444444444444444444444444444444"),
5188                         delayed_payment_basepoint: public_from_secret_hex(&secp_ctx, "1552dfba4f6cf29a62a0af13c8d6981d36d0ef8d61ba10fb0fe90da7634d7e13"),
5189                         htlc_basepoint: public_from_secret_hex(&secp_ctx, "4444444444444444444444444444444444444444444444444444444444444444")
5190                 };
5191                 chan.channel_transaction_parameters.counterparty_parameters = Some(
5192                         CounterpartyChannelTransactionParameters {
5193                                 pubkeys: counterparty_pubkeys.clone(),
5194                                 selected_contest_delay: 144
5195                         });
5196                 chan.channel_transaction_parameters.funding_outpoint = Some(funding_info);
5197                 signer.ready_channel(&chan.channel_transaction_parameters);
5198
5199                 assert_eq!(counterparty_pubkeys.payment_point.serialize()[..],
5200                            hex::decode("032c0b7cf95324a07d05398b240174dc0c2be444d96b159aa6c7f7b1e668680991").unwrap()[..]);
5201
5202                 assert_eq!(counterparty_pubkeys.funding_pubkey.serialize()[..],
5203                            hex::decode("030e9f7b623d2ccc7c9bd44d66d5ce21ce504c0acf6385a132cec6d3c39fa711c1").unwrap()[..]);
5204
5205                 assert_eq!(counterparty_pubkeys.htlc_basepoint.serialize()[..],
5206                            hex::decode("032c0b7cf95324a07d05398b240174dc0c2be444d96b159aa6c7f7b1e668680991").unwrap()[..]);
5207
5208                 // We can't just use build_holder_transaction_keys here as the per_commitment_secret is not
5209                 // derived from a commitment_seed, so instead we copy it here and call
5210                 // build_commitment_transaction.
5211                 let delayed_payment_base = &chan.holder_signer.pubkeys().delayed_payment_basepoint;
5212                 let per_commitment_secret = SecretKey::from_slice(&hex::decode("1f1e1d1c1b1a191817161514131211100f0e0d0c0b0a09080706050403020100").unwrap()[..]).unwrap();
5213                 let per_commitment_point = PublicKey::from_secret_key(&secp_ctx, &per_commitment_secret);
5214                 let htlc_basepoint = &chan.holder_signer.pubkeys().htlc_basepoint;
5215                 let keys = TxCreationKeys::derive_new(&secp_ctx, &per_commitment_point, delayed_payment_base, htlc_basepoint, &counterparty_pubkeys.revocation_basepoint, &counterparty_pubkeys.htlc_basepoint).unwrap();
5216
5217                 macro_rules! test_commitment {
5218                         ( $counterparty_sig_hex: expr, $sig_hex: expr, $tx_hex: expr, {
5219                                 $( { $htlc_idx: expr, $counterparty_htlc_sig_hex: expr, $htlc_sig_hex: expr, $htlc_tx_hex: expr } ), *
5220                         } ) => { {
5221                                 let (commitment_tx, htlcs): (_, Vec<HTLCOutputInCommitment>) = {
5222                                         let mut res = chan.build_commitment_transaction(0xffffffffffff - 42, &keys, true, false, chan.feerate_per_kw, &logger);
5223
5224                                         let htlcs = res.2.drain(..)
5225                                                 .filter_map(|(htlc, _)| if htlc.transaction_output_index.is_some() { Some(htlc) } else { None })
5226                                                 .collect();
5227                                         (res.0, htlcs)
5228                                 };
5229                                 let trusted_tx = commitment_tx.trust();
5230                                 let unsigned_tx = trusted_tx.built_transaction();
5231                                 let redeemscript = chan.get_funding_redeemscript();
5232                                 let counterparty_signature = Signature::from_der(&hex::decode($counterparty_sig_hex).unwrap()[..]).unwrap();
5233                                 let sighash = unsigned_tx.get_sighash_all(&redeemscript, chan.channel_value_satoshis);
5234                                 secp_ctx.verify(&sighash, &counterparty_signature, chan.counterparty_funding_pubkey()).unwrap();
5235
5236                                 let mut per_htlc: Vec<(HTLCOutputInCommitment, Option<Signature>)> = Vec::new();
5237                                 per_htlc.clear(); // Don't warn about excess mut for no-HTLC calls
5238                                 let mut counterparty_htlc_sigs = Vec::new();
5239                                 counterparty_htlc_sigs.clear(); // Don't warn about excess mut for no-HTLC calls
5240                                 $({
5241                                         let remote_signature = Signature::from_der(&hex::decode($counterparty_htlc_sig_hex).unwrap()[..]).unwrap();
5242                                         per_htlc.push((htlcs[$htlc_idx].clone(), Some(remote_signature)));
5243                                         counterparty_htlc_sigs.push(remote_signature);
5244                                 })*
5245                                 assert_eq!(htlcs.len(), per_htlc.len());
5246
5247                                 let holder_commitment_tx = HolderCommitmentTransaction::new(
5248                                         commitment_tx.clone(),
5249                                         counterparty_signature,
5250                                         counterparty_htlc_sigs,
5251                                         &chan.holder_signer.pubkeys().funding_pubkey,
5252                                         chan.counterparty_funding_pubkey()
5253                                 );
5254                                 let (holder_sig, htlc_sigs) = signer.sign_holder_commitment_and_htlcs(&holder_commitment_tx, &secp_ctx).unwrap();
5255                                 assert_eq!(Signature::from_der(&hex::decode($sig_hex).unwrap()[..]).unwrap(), holder_sig, "holder_sig");
5256
5257                                 let funding_redeemscript = chan.get_funding_redeemscript();
5258                                 let tx = holder_commitment_tx.add_holder_sig(&funding_redeemscript, holder_sig);
5259                                 assert_eq!(serialize(&tx)[..], hex::decode($tx_hex).unwrap()[..], "tx");
5260
5261                                 // ((htlc, counterparty_sig), (index, holder_sig))
5262                                 let mut htlc_sig_iter = holder_commitment_tx.htlcs().iter().zip(&holder_commitment_tx.counterparty_htlc_sigs).zip(htlc_sigs.iter().enumerate());
5263
5264                                 $({
5265                                         let remote_signature = Signature::from_der(&hex::decode($counterparty_htlc_sig_hex).unwrap()[..]).unwrap();
5266
5267                                         let ref htlc = htlcs[$htlc_idx];
5268                                         let htlc_tx = chan.build_htlc_transaction(&unsigned_tx.txid, &htlc, true, &keys, chan.feerate_per_kw);
5269                                         let htlc_redeemscript = chan_utils::get_htlc_redeemscript(&htlc, &keys);
5270                                         let htlc_sighash = Message::from_slice(&bip143::SigHashCache::new(&htlc_tx).signature_hash(0, &htlc_redeemscript, htlc.amount_msat / 1000, SigHashType::All)[..]).unwrap();
5271                                         secp_ctx.verify(&htlc_sighash, &remote_signature, &keys.countersignatory_htlc_key).unwrap();
5272
5273                                         let mut preimage: Option<PaymentPreimage> = None;
5274                                         if !htlc.offered {
5275                                                 for i in 0..5 {
5276                                                         let out = PaymentHash(Sha256::hash(&[i; 32]).into_inner());
5277                                                         if out == htlc.payment_hash {
5278                                                                 preimage = Some(PaymentPreimage([i; 32]));
5279                                                         }
5280                                                 }
5281
5282                                                 assert!(preimage.is_some());
5283                                         }
5284
5285                                         let htlc_sig = htlc_sig_iter.next().unwrap();
5286                                         assert_eq!((htlc_sig.0).0.transaction_output_index, Some($htlc_idx), "output index");
5287
5288                                         let signature = Signature::from_der(&hex::decode($htlc_sig_hex).unwrap()[..]).unwrap();
5289                                         assert_eq!(signature, *(htlc_sig.1).1, "htlc sig");
5290                                         let index = (htlc_sig.1).0;
5291                                         let channel_parameters = chan.channel_transaction_parameters.as_holder_broadcastable();
5292                                         let trusted_tx = holder_commitment_tx.trust();
5293                                         assert_eq!(serialize(&trusted_tx.get_signed_htlc_tx(&channel_parameters, index, &(htlc_sig.0).1, (htlc_sig.1).1, &preimage))[..],
5294                                                         hex::decode($htlc_tx_hex).unwrap()[..], "htlc tx");
5295                                 })*
5296                                 assert!(htlc_sig_iter.next().is_none());
5297                         } }
5298                 }
5299
5300                 // simple commitment tx with no HTLCs
5301                 chan.value_to_self_msat = 7000000000;
5302
5303                 test_commitment!("3045022100c3127b33dcc741dd6b05b1e63cbd1a9a7d816f37af9b6756fa2376b056f032370220408b96279808fe57eb7e463710804cdf4f108388bc5cf722d8c848d2c7f9f3b0",
5304                                                  "30440220616210b2cc4d3afb601013c373bbd8aac54febd9f15400379a8cb65ce7deca60022034236c010991beb7ff770510561ae8dc885b8d38d1947248c38f2ae055647142",
5305                                                  "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", {});
5306
5307                 chan.pending_inbound_htlcs.push({
5308                         let mut out = InboundHTLCOutput{
5309                                 htlc_id: 0,
5310                                 amount_msat: 1000000,
5311                                 cltv_expiry: 500,
5312                                 payment_hash: PaymentHash([0; 32]),
5313                                 state: InboundHTLCState::Committed,
5314                         };
5315                         out.payment_hash.0 = Sha256::hash(&hex::decode("0000000000000000000000000000000000000000000000000000000000000000").unwrap()).into_inner();
5316                         out
5317                 });
5318                 chan.pending_inbound_htlcs.push({
5319                         let mut out = InboundHTLCOutput{
5320                                 htlc_id: 1,
5321                                 amount_msat: 2000000,
5322                                 cltv_expiry: 501,
5323                                 payment_hash: PaymentHash([0; 32]),
5324                                 state: InboundHTLCState::Committed,
5325                         };
5326                         out.payment_hash.0 = Sha256::hash(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()).into_inner();
5327                         out
5328                 });
5329                 chan.pending_outbound_htlcs.push({
5330                         let mut out = OutboundHTLCOutput{
5331                                 htlc_id: 2,
5332                                 amount_msat: 2000000,
5333                                 cltv_expiry: 502,
5334                                 payment_hash: PaymentHash([0; 32]),
5335                                 state: OutboundHTLCState::Committed,
5336                                 source: HTLCSource::dummy(),
5337                         };
5338                         out.payment_hash.0 = Sha256::hash(&hex::decode("0202020202020202020202020202020202020202020202020202020202020202").unwrap()).into_inner();
5339                         out
5340                 });
5341                 chan.pending_outbound_htlcs.push({
5342                         let mut out = OutboundHTLCOutput{
5343                                 htlc_id: 3,
5344                                 amount_msat: 3000000,
5345                                 cltv_expiry: 503,
5346                                 payment_hash: PaymentHash([0; 32]),
5347                                 state: OutboundHTLCState::Committed,
5348                                 source: HTLCSource::dummy(),
5349                         };
5350                         out.payment_hash.0 = Sha256::hash(&hex::decode("0303030303030303030303030303030303030303030303030303030303030303").unwrap()).into_inner();
5351                         out
5352                 });
5353                 chan.pending_inbound_htlcs.push({
5354                         let mut out = InboundHTLCOutput{
5355                                 htlc_id: 4,
5356                                 amount_msat: 4000000,
5357                                 cltv_expiry: 504,
5358                                 payment_hash: PaymentHash([0; 32]),
5359                                 state: InboundHTLCState::Committed,
5360                         };
5361                         out.payment_hash.0 = Sha256::hash(&hex::decode("0404040404040404040404040404040404040404040404040404040404040404").unwrap()).into_inner();
5362                         out
5363                 });
5364
5365                 // commitment tx with all five HTLCs untrimmed (minimum feerate)
5366                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5367                 chan.feerate_per_kw = 0;
5368
5369                 test_commitment!("3044022009b048187705a8cbc9ad73adbe5af148c3d012e1f067961486c822c7af08158c022006d66f3704cfab3eb2dc49dae24e4aa22a6910fc9b424007583204e3621af2e5",
5370                                  "304402206fc2d1f10ea59951eefac0b4b7c396a3c3d87b71ff0b019796ef4535beaf36f902201765b0181e514d04f4c8ad75659d7037be26cdb3f8bb6f78fe61decef484c3ea",
5371                                  "02000000000101bef67e4e2fb9ddeeb3461973cd4c62abb35050b1add772995b820b584a488489000000000038b02b8007e80300000000000022002052bfef0479d7b293c27e0f1eb294bea154c63a3294ef092c19af51409bce0e2ad007000000000000220020403d394747cae42e98ff01734ad5c08f82ba123d3d9a620abda88989651e2ab5d007000000000000220020748eba944fedc8827f6b06bc44678f93c0f9e6078b35c6331ed31e75f8ce0c2db80b000000000000220020c20b5d1f8584fd90443e7b7b720136174fa4b9333c261d04dbbd012635c0f419a00f0000000000002200208c48d15160397c9731df9bc3b236656efb6665fbfe92b4a6878e88a499f741c4c0c62d0000000000160014cc1b07838e387deacd0e5232e1e8b49f4c29e484e0a06a00000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e040047304402206fc2d1f10ea59951eefac0b4b7c396a3c3d87b71ff0b019796ef4535beaf36f902201765b0181e514d04f4c8ad75659d7037be26cdb3f8bb6f78fe61decef484c3ea01473044022009b048187705a8cbc9ad73adbe5af148c3d012e1f067961486c822c7af08158c022006d66f3704cfab3eb2dc49dae24e4aa22a6910fc9b424007583204e3621af2e501475221023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb21030e9f7b623d2ccc7c9bd44d66d5ce21ce504c0acf6385a132cec6d3c39fa711c152ae3e195220", {
5372
5373                                   { 0,
5374                                   "3045022100d9e29616b8f3959f1d3d7f7ce893ffedcdc407717d0de8e37d808c91d3a7c50d022078c3033f6d00095c8720a4bc943c1b45727818c082e4e3ddbc6d3116435b624b",
5375                                   "30440220636de5682ef0c5b61f124ec74e8aa2461a69777521d6998295dcea36bc3338110220165285594b23c50b28b82df200234566628a27bcd17f7f14404bd865354eb3ce",
5376                                   "02000000000101ab84ff284f162cfbfef241f853b47d4368d171f9e2a1445160cd591c4c7d882b00000000000000000001e8030000000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e0500483045022100d9e29616b8f3959f1d3d7f7ce893ffedcdc407717d0de8e37d808c91d3a7c50d022078c3033f6d00095c8720a4bc943c1b45727818c082e4e3ddbc6d3116435b624b014730440220636de5682ef0c5b61f124ec74e8aa2461a69777521d6998295dcea36bc3338110220165285594b23c50b28b82df200234566628a27bcd17f7f14404bd865354eb3ce012000000000000000000000000000000000000000000000000000000000000000008a76a91414011f7254d96b819c76986c277d115efce6f7b58763ac67210394854aa6eab5b2a8122cc726e9dded053a2184d88256816826d6231c068d4a5b7c8201208763a914b8bcb07f6344b42ab04250c86a6e8b75d3fdbbc688527c21030d417a46946384f88d5f3337267c5e579765875dc4daca813e21734b140639e752ae677502f401b175ac686800000000" },
5377
5378                                   { 1,
5379                                   "30440220649fe8b20e67e46cbb0d09b4acea87dbec001b39b08dee7bdd0b1f03922a8640022037c462dff79df501cecfdb12ea7f4de91f99230bb544726f6e04527b1f896004",
5380                                   "3045022100803159dee7935dba4a1d36a61055ce8fd62caa528573cc221ae288515405a252022029c59e7cffce374fe860100a4a63787e105c3cf5156d40b12dd53ff55ac8cf3f",
5381                                   "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" },
5382
5383                                   { 2,
5384                                   "30440220770fc321e97a19f38985f2e7732dd9fe08d16a2efa4bcbc0429400a447faf49102204d40b417f3113e1b0944ae0986f517564ab4acd3d190503faf97a6e420d43352",
5385                                   "3045022100a437cc2ce77400ecde441b3398fea3c3ad8bdad8132be818227fe3c5b8345989022069d45e7fa0ae551ec37240845e2c561ceb2567eacf3076a6a43a502d05865faa",
5386                                   "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" },
5387
5388                                   { 3,
5389                                   "304402207bcbf4f60a9829b05d2dbab84ed593e0291836be715dc7db6b72a64caf646af802201e489a5a84f7c5cc130398b841d138d031a5137ac8f4c49c770a4959dc3c1363",
5390                                   "304402203121d9b9c055f354304b016a36662ee99e1110d9501cb271b087ddb6f382c2c80220549882f3f3b78d9c492de47543cb9a697cecc493174726146536c5954dac7487",
5391                                   "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" },
5392
5393                                   { 4,
5394                                   "3044022076dca5cb81ba7e466e349b7128cdba216d4d01659e29b96025b9524aaf0d1899022060de85697b88b21c749702b7d2cfa7dfeaa1f472c8f1d7d9c23f2bf968464b87",
5395                                   "3045022100d9080f103cc92bac15ec42464a95f070c7fb6925014e673ee2ea1374d36a7f7502200c65294d22eb20d48564954d5afe04a385551919d8b2ddb4ae2459daaeee1d95",
5396                                   "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" }
5397                 } );
5398
5399                 // commitment tx with seven outputs untrimmed (maximum feerate)
5400                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5401                 chan.feerate_per_kw = 647;
5402
5403                 test_commitment!("3045022100a135f9e8a5ed25f7277446c67956b00ce6f610ead2bdec2c2f686155b7814772022059f1f6e1a8b336a68efcc1af3fe4d422d4827332b5b067501b099c47b7b5b5ee",
5404                                  "30450221009ec15c687898bb4da8b3a833e5ab8bfc51ec6e9202aaa8e66611edfd4a85ed1102203d7183e45078b9735c93450bc3415d3e5a8c576141a711ec6ddcb4a893926bb7",
5405                                  "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", {
5406
5407                                   { 0,
5408                                   "30450221008437627f9ad84ac67052e2a414a4367b8556fd1f94d8b02590f89f50525cd33502205b9c21ff6e7fc864f2352746ad8ba59182510819acb644e25b8a12fc37bbf24f",
5409                                   "30440220344b0deb055230d01703e6c7acd45853c4af2328b49b5d8af4f88a060733406602202ea64f2a43d5751edfe75503cbc35a62e3141b5ed032fa03360faf4ca66f670b",
5410                                   "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" },
5411
5412                                   { 1,
5413                                   "304402205a67f92bf6845cf2892b48d874ac1daf88a36495cf8a06f93d83180d930a6f75022031da1621d95c3f335cc06a3056cf960199dae600b7cf89088f65fc53cdbef28c",
5414                                   "30450221009e5e3822b0185c6799a95288c597b671d6cc69ab80f43740f00c6c3d0752bdda02206da947a74bd98f3175324dc56fdba86cc783703a120a6f0297537e60632f4c7f",
5415                                   "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" },
5416
5417                                   { 2,
5418                                   "30440220437e21766054a3eef7f65690c5bcfa9920babbc5af92b819f772f6ea96df6c7402207173622024bd97328cfb26c6665e25c2f5d67c319443ccdc60c903217005d8c8",
5419                                   "3045022100fcfc47e36b712624677626cef3dc1d67f6583bd46926a6398fe6b00b0c9a37760220525788257b187fc775c6370d04eadf34d06f3650a63f8df851cee0ecb47a1673",
5420                                   "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" },
5421
5422                                   { 3,
5423                                   "304402207436e10737e4df499fc051686d3e11a5bb2310e4d1f1e691d287cef66514791202207cb58e71a6b7a42dd001b7e3ae672ea4f71ea3e1cd412b742e9124abb0739c64",
5424                                   "3045022100e78211b8409afb7255ffe37337da87f38646f1faebbdd61bc1920d69e3ead67a02201a626305adfcd16bfb7e9340928d9b6305464eab4aa4c4a3af6646e9b9f69dee",
5425                                   "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" },
5426
5427                                   { 4,
5428                                   "30450221009acd6a827a76bfee50806178dfe0495cd4e1d9c58279c194c7b01520fe68cb8d022024d439047c368883e570997a7d40f0b430cb5a742f507965e7d3063ae3feccca",
5429                                   "3044022048762cf546bbfe474f1536365ea7c416e3c0389d60558bc9412cb148fb6ab68202207215d7083b75c96ff9d2b08c59c34e287b66820f530b486a9aa4cdd9c347d5b9",
5430                                   "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" }
5431                 } );
5432
5433                 // commitment tx with six outputs untrimmed (minimum feerate)
5434                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5435                 chan.feerate_per_kw = 648;
5436
5437                 test_commitment!("304402203948f900a5506b8de36a4d8502f94f21dd84fd9c2314ab427d52feaa7a0a19f2022059b6a37a4adaa2c5419dc8aea63c6e2a2ec4c4bde46207f6dc1fcd22152fc6e5",
5438                                  "3045022100b15f72908ba3382a34ca5b32519240a22300cc6015b6f9418635fb41f3d01d8802207adb331b9ed1575383dca0f2355e86c173802feecf8298fbea53b9d4610583e9",
5439                                  "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", {
5440
5441                                   { 0,
5442                                   "3045022100a031202f3be94678f0e998622ee95ebb6ada8da1e9a5110228b5e04a747351e4022010ca6a21e18314ed53cfaae3b1f51998552a61a468e596368829a50ce40110e0",
5443                                   "304502210097e1873b57267730154595187a34949d3744f52933070c74757005e61ce2112e02204ecfba2aa42d4f14bdf8bad4206bb97217b702e6c433e0e1b0ce6587e6d46ec6",
5444                                   "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" },
5445
5446                                   { 1,
5447                                   "304402202361012a634aee7835c5ecdd6413dcffa8f404b7e77364c792cff984e4ee71e90220715c5e90baa08daa45a7439b1ee4fa4843ed77b19c058240b69406606d384124",
5448                                   "3044022019de73b00f1d818fb388e83b2c8c31f6bce35ac624e215bc12f88f9dc33edf48022006ff814bb9f700ee6abc3294e146fac3efd4f13f0005236b41c0a946ee00c9ae",
5449                                   "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" },
5450
5451                                   { 2,
5452                                   "304402207e8e82cd71ed4febeb593732c260456836e97d81896153ecd2b3cf320ca6861702202dd4a30f68f98ced7cc56a36369ac1fdd978248c5ff4ed204fc00cc625532989",
5453                                   "3045022100bd0be6100c4fd8f102ec220e1b053e4c4e2ecca25615490150007b40d314dc3902201a1e0ea266965b43164d9e6576f58fa6726d42883dd1c3996d2925c2e2260796",
5454                                   "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" },
5455
5456                                   { 3,
5457                                   "3044022024cd52e4198c8ae0e414a86d86b5a65ea7450f2eb4e783096736d93395eca5ce022078f0094745b45be4d4b2b04dd5978c9e66ba49109e5704403e84aaf5f387d6be",
5458                                   "3045022100bbfb9d0a946d420807c86e985d636cceb16e71c3694ed186316251a00cbd807202207773223f9a337e145f64673825be9b30d07ef1542c82188b264bedcf7cda78c6",
5459                                   "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" }
5460                 } );
5461
5462                 // commitment tx with six outputs untrimmed (maximum feerate)
5463                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5464                 chan.feerate_per_kw = 2069;
5465
5466                 test_commitment!("304502210090b96a2498ce0c0f2fadbec2aab278fed54c1a7838df793ec4d2c78d96ec096202204fdd439c50f90d483baa7b68feeef4bd33bc277695405447bcd0bfb2ca34d7bc",
5467                                  "3045022100ad9a9bbbb75d506ca3b716b336ee3cf975dd7834fcf129d7dd188146eb58a8b4022061a759ee417339f7fe2ea1e8deb83abb6a74db31a09b7648a932a639cda23e33",
5468                                  "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", {
5469
5470                                   { 0,
5471                                   "3045022100f33513ee38abf1c582876f921f8fddc06acff48e04515532a32d3938de938ffd02203aa308a2c1863b7d6fdf53159a1465bf2e115c13152546cc5d74483ceaa7f699",
5472                                   "3045022100a637902a5d4c9ba9e7c472a225337d5aac9e2e3f6744f76e237132e7619ba0400220035c60d784a031c0d9f6df66b7eab8726a5c25397399ee4aa960842059eb3f9d",
5473                                   "02000000000101adbe717a63fb658add30ada1e6e12ed257637581898abe475c11d7bbcd65bd4d0000000000000000000175020000000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e0500483045022100f33513ee38abf1c582876f921f8fddc06acff48e04515532a32d3938de938ffd02203aa308a2c1863b7d6fdf53159a1465bf2e115c13152546cc5d74483ceaa7f69901483045022100a637902a5d4c9ba9e7c472a225337d5aac9e2e3f6744f76e237132e7619ba0400220035c60d784a031c0d9f6df66b7eab8726a5c25397399ee4aa960842059eb3f9d01008576a91414011f7254d96b819c76986c277d115efce6f7b58763ac67210394854aa6eab5b2a8122cc726e9dded053a2184d88256816826d6231c068d4a5b7c820120876475527c21030d417a46946384f88d5f3337267c5e579765875dc4daca813e21734b140639e752ae67a914b43e1b38138a41b37f7cd9a1d274bc63e3a9b5d188ac6868f6010000" },
5474
5475                                   { 1,
5476                                   "3045022100ce07682cf4b90093c22dc2d9ab2a77ad6803526b655ef857221cc96af5c9e0bf02200f501cee22e7a268af40b555d15a8237c9f36ad67ef1841daf9f6a0267b1e6df",
5477                                   "3045022100e57e46234f8782d3ff7aa593b4f7446fb5316c842e693dc63ee324fd49f6a1c302204a2f7b44c48bd26e1554422afae13153eb94b29d3687b733d18930615fb2db61",
5478                                   "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" },
5479
5480                                   { 2,
5481                                   "3045022100e3e35492e55f82ec0bc2f317ffd7a486d1f7024330fe9743c3559fc39f32ef0c02203d1d4db651fc388a91d5ad8ecdd8e83673063bc8eefe27cfd8c189090e3a23e0",
5482                                   "3044022068613fb1b98eb3aec7f44c5b115b12343c2f066c4277c82b5f873dfe68f37f50022028109b4650f3f528ca4bfe9a467aff2e3e43893b61b5159157119d5d95cf1c18",
5483                                   "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" },
5484
5485                                   { 3,
5486                                   "304402207475aeb0212ef9bf5130b60937817ad88c9a87976988ef1f323f026148cc4a850220739fea17ad3257dcad72e509c73eebe86bee30b178467b9fdab213d631b109df",
5487                                   "3045022100d315522e09e7d53d2a659a79cb67fef56d6c4bddf3f46df6772d0d20a7beb7c8022070bcc17e288607b6a72be0bd83368bb6d53488db266c1cdb4d72214e4f02ac33",
5488                                   "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" }
5489                 } );
5490
5491                 // commitment tx with five outputs untrimmed (minimum feerate)
5492                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5493                 chan.feerate_per_kw = 2070;
5494
5495                 test_commitment!("304402204ca1ba260dee913d318271d86e10ca0f5883026fb5653155cff600fb40895223022037b145204b7054a40e08bb1fefbd826f827b40838d3e501423bcc57924bcb50c",
5496                                  "3044022001014419b5ba00e083ac4e0a85f19afc848aacac2d483b4b525d15e2ae5adbfe022015ebddad6ee1e72b47cb09f3e78459da5be01ccccd95dceca0e056a00cc773c1",
5497                                  "02000000000101bef67e4e2fb9ddeeb3461973cd4c62abb35050b1add772995b820b584a488489000000000038b02b8005d007000000000000220020403d394747cae42e98ff01734ad5c08f82ba123d3d9a620abda88989651e2ab5b80b000000000000220020c20b5d1f8584fd90443e7b7b720136174fa4b9333c261d04dbbd012635c0f419a00f0000000000002200208c48d15160397c9731df9bc3b236656efb6665fbfe92b4a6878e88a499f741c4c0c62d0000000000160014cc1b07838e387deacd0e5232e1e8b49f4c29e484da966a00000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e0400473044022001014419b5ba00e083ac4e0a85f19afc848aacac2d483b4b525d15e2ae5adbfe022015ebddad6ee1e72b47cb09f3e78459da5be01ccccd95dceca0e056a00cc773c10147304402204ca1ba260dee913d318271d86e10ca0f5883026fb5653155cff600fb40895223022037b145204b7054a40e08bb1fefbd826f827b40838d3e501423bcc57924bcb50c01475221023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb21030e9f7b623d2ccc7c9bd44d66d5ce21ce504c0acf6385a132cec6d3c39fa711c152ae3e195220", {
5498
5499                                   { 0,
5500                                   "304402205f6b6d12d8d2529fb24f4445630566cf4abbd0f9330ab6c2bdb94222d6a2a0c502202f556258ae6f05b193749e4c541dfcc13b525a5422f6291f073f15617ba8579b",
5501                                   "30440220150b11069454da70caf2492ded9e0065c9a57f25ac2a4c52657b1d15b6c6ed85022068a38833b603c8892717206383611bad210f1cbb4b1f87ea29c6c65b9e1cb3e5",
5502                                   "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" },
5503
5504                                   { 1,
5505                                   "3045022100f960dfb1c9aee7ce1437efa65b523e399383e8149790e05d8fed27ff6e42fe0002202fe8613e062ffe0b0c518cc4101fba1c6de70f64a5bcc7ae663f2efae43b8546",
5506                                   "30450221009a6ed18e6873bc3644332a6ee21c152a5b102821865350df7a8c74451a51f9f2022050d801fb4895d7d7fbf452824c0168347f5c0cbe821cf6a97a63af5b8b2563c6",
5507                                   "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" },
5508
5509                                   { 2,
5510                                   "3045022100ae5fc7717ae684bc1fcf9020854e5dbe9842c9e7472879ac06ff95ac2bb10e4e022057728ada4c00083a3e65493fb5d50a232165948a1a0f530ef63185c2c8c56504",
5511                                   "30440220408ad3009827a8fccf774cb285587686bfb2ed041f89a89453c311ce9c8ee0f902203c7392d9f8306d3a46522a66bd2723a7eb2628cb2d9b34d4c104f1766bf37502",
5512                                   "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" }
5513                 } );
5514
5515                 // commitment tx with five outputs untrimmed (maximum feerate)
5516                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5517                 chan.feerate_per_kw = 2194;
5518
5519                 test_commitment!("304402204bb3d6e279d71d9da414c82de42f1f954267c762b2e2eb8b76bc3be4ea07d4b0022014febc009c5edc8c3fc5d94015de163200f780046f1c293bfed8568f08b70fb3",
5520                                  "3044022072c2e2b1c899b2242656a537dde2892fa3801be0d6df0a87836c550137acde8302201654aa1974d37a829083c3ba15088689f30b56d6a4f6cb14c7bad0ee3116d398",
5521                                  "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", {
5522
5523                                   { 0,
5524                                   "3045022100939726680351a7856c1bc386d4a1f422c7d29bd7b56afc139570f508474e6c40022023175a799ccf44c017fbaadb924c40b2a12115a5b7d0dfd3228df803a2de8450",
5525                                   "304502210099c98c2edeeee6ec0fb5f3bea8b79bb016a2717afa9b5072370f34382de281d302206f5e2980a995e045cf90a547f0752a7ee99d48547bc135258fe7bc07e0154301",
5526                                   "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" },
5527
5528                                   { 1,
5529                                   "3044022021bb883bf324553d085ba2e821cad80c28ef8b303dbead8f98e548783c02d1600220638f9ef2a9bba25869afc923f4b5dc38be3bb459f9efa5d869392d5f7779a4a0",
5530                                   "3045022100fd85bd7697b89c08ec12acc8ba89b23090637d83abd26ca37e01ae93e67c367302202b551fe69386116c47f984aab9c8dfd25d864dcde5d3389cfbef2447a85c4b77",
5531                                   "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" },
5532
5533                                   { 2,
5534                                   "3045022100c9e6f0454aa598b905a35e641a70cc9f67b5f38cc4b00843a041238c4a9f1c4a0220260a2822a62da97e44583e837245995ca2e36781769c52f19e498efbdcca262b",
5535                                   "30450221008a9f2ea24cd455c2b64c1472a5fa83865b0a5f49a62b661801e884cf2849af8302204d44180e50bf6adfcf1c1e581d75af91aba4e28681ce4a5ee5f3cbf65eca10f3",
5536                                   "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" }
5537                 } );
5538
5539                 // commitment tx with four outputs untrimmed (minimum feerate)
5540                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5541                 chan.feerate_per_kw = 2195;
5542
5543                 test_commitment!("304402201a8c1b1f9671cd9e46c7323a104d7047cc48d3ee80d40d4512e0c72b8dc65666022066d7f9a2ce18c9eb22d2739ffcce05721c767f9b607622a31b6ea5793ddce403",
5544                                  "3044022044d592025b610c0d678f65032e87035cdfe89d1598c522cc32524ae8172417c30220749fef9d5b2ae8cdd91ece442ba8809bc891efedae2291e578475f97715d1767",
5545                                  "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", {
5546
5547                                   { 0,
5548                                   "3045022100e57b845066a06ee7c2cbfc29eabffe52daa9bf6f6de760066d04df9f9b250e0002202ffb197f0e6e0a77a75a9aff27014bd3de83b7f748d7efef986abe655e1dd50e",
5549                                   "3045022100ecc8c6529d0b2316d046f0f0757c1e1c25a636db168ec4f3aa1b9278df685dc0022067ae6b65e936f1337091f7b18a15935b608c5f2cdddb2f892ed0babfdd376d76",
5550                                   "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" },
5551
5552                                   { 1,
5553                                   "3045022100d193b7ecccad8057571620a0b1ffa6c48e9483311723b59cf536043b20bc51550220546d4bd37b3b101ecda14f6c907af46ec391abce1cd9c7ce22b1a62b534f2f2a",
5554                                   "3044022014d66f11f9cacf923807eba49542076c5fe5cccf252fb08fe98c78ef3ca6ab5402201b290dbe043cc512d9d78de074a5a129b8759bc6a6c546b190d120b690bd6e82",
5555                                   "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" }
5556                 } );
5557
5558                 // commitment tx with four outputs untrimmed (maximum feerate)
5559                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5560                 chan.feerate_per_kw = 3702;
5561
5562                 test_commitment!("304502210092a587aeb777f869e7ff0d7898ea619ee26a3dacd1f3672b945eea600be431100220077ee9eae3528d15251f2a52b607b189820e57a6ccfac8d1af502b132ee40169",
5563                                  "3045022100e5efb73c32d32da2d79702299b6317de6fb24a60476e3855926d78484dd1b3c802203557cb66a42c944ef06e00bcc4da35a5bcb2f185aab0f8e403e519e1d66aaf75",
5564                                  "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", {
5565
5566                                   { 0,
5567                                   "304402206fa54c11f98c3bae1e93df43fc7affeb05b476bf8060c03e29c377c69bc08e8b0220672701cce50d5c379ff45a5d2cfe48ac44973adb066ac32608e21221d869bb89",
5568                                   "304402206e36c683ebf2cb16bcef3d5439cf8b53cd97280a365ed8acd7abb85a8ba5f21c02206e8621edfc2a5766cbc96eb67fd501127ff163eb6b85518a39f7d4974aef126f",
5569                                   "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" },
5570
5571                                   { 1,
5572                                   "3044022057649739b0eb74d541ead0dfdb3d4b2c15aa192720031044c3434c67812e5ca902201e5ede42d960ae551707f4a6b34b09393cf4dee2418507daa022e3550dbb5817",
5573                                   "304402207faad26678c8850e01b4a0696d60841f7305e1832b786110ee9075cb92ed14a30220516ef8ee5dfa80824ea28cbcec0dd95f8b847146257c16960db98507db15ffdc",
5574                                   "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" }
5575                 } );
5576
5577                 // commitment tx with three outputs untrimmed (minimum feerate)
5578                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5579                 chan.feerate_per_kw = 3703;
5580
5581                 test_commitment!("3045022100b495d239772a237ff2cf354b1b11be152fd852704cb184e7356d13f2fb1e5e430220723db5cdb9cbd6ead7bfd3deb419cf41053a932418cbb22a67b581f40bc1f13e",
5582                                  "304402201b736d1773a124c745586217a75bed5f66c05716fbe8c7db4fdb3c3069741cdd02205083f39c321c1bcadfc8d97e3c791a66273d936abac0c6a2fde2ed46019508e1",
5583                                  "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", {
5584
5585                                   { 0,
5586                                   "3045022100c34c61735f93f2e324cc873c3b248111ccf8f6db15d5969583757010d4ad2b4602207867bb919b2ddd6387873e425345c9b7fd18d1d66aba41f3607bc2896ef3c30a",
5587                                   "3045022100988c143e2110067117d2321bdd4bd16ca1734c98b29290d129384af0962b634e02206c1b02478878c5f547018b833986578f90c3e9be669fe5788ad0072a55acbb05",
5588                                   "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" }
5589                 } );
5590
5591                 // commitment tx with three outputs untrimmed (maximum feerate)
5592                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5593                 chan.feerate_per_kw = 4914;
5594
5595                 test_commitment!("3045022100b4b16d5f8cc9fc4c1aff48831e832a0d8990e133978a66e302c133550954a44d022073573ce127e2200d316f6b612803a5c0c97b8d20e1e44dbe2ac0dd2fb8c95244",
5596                                  "3045022100d72638bc6308b88bb6d45861aae83e5b9ff6e10986546e13bce769c70036e2620220320be7c6d66d22f30b9fcd52af66531505b1310ca3b848c19285b38d8a1a8c19",
5597                                  "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", {
5598
5599                                   { 0,
5600                                   "3045022100f43591c156038ba217756006bb3c55f7d113a325cdd7d9303c82115372858d68022016355b5aadf222bc8d12e426c75f4a03423917b2443a103eb2a498a3a2234374",
5601                                   "30440220585dee80fafa264beac535c3c0bb5838ac348b156fdc982f86adc08dfc9bfd250220130abb82f9f295cc9ef423dcfef772fde2acd85d9df48cc538981d26a10a9c10",
5602                                   "02000000000101a9172908eace869cc35128c31fc2ab502f72e4dff31aab23e0244c4b04b11ab00000000000000000000122020000000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e0500483045022100f43591c156038ba217756006bb3c55f7d113a325cdd7d9303c82115372858d68022016355b5aadf222bc8d12e426c75f4a03423917b2443a103eb2a498a3a2234374014730440220585dee80fafa264beac535c3c0bb5838ac348b156fdc982f86adc08dfc9bfd250220130abb82f9f295cc9ef423dcfef772fde2acd85d9df48cc538981d26a10a9c10012004040404040404040404040404040404040404040404040404040404040404048a76a91414011f7254d96b819c76986c277d115efce6f7b58763ac67210394854aa6eab5b2a8122cc726e9dded053a2184d88256816826d6231c068d4a5b7c8201208763a91418bc1a114ccf9c052d3d23e28d3b0a9d1227434288527c21030d417a46946384f88d5f3337267c5e579765875dc4daca813e21734b140639e752ae677502f801b175ac686800000000" }
5603                 } );
5604
5605                 // commitment tx with two outputs untrimmed (minimum feerate)
5606                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5607                 chan.feerate_per_kw = 4915;
5608
5609                 test_commitment!("304402203a286936e74870ca1459c700c71202af0381910a6bfab687ef494ef1bc3e02c902202506c362d0e3bee15e802aa729bf378e051644648253513f1c085b264cc2a720",
5610                                  "30450221008a953551f4d67cb4df3037207fc082ddaf6be84d417b0bd14c80aab66f1b01a402207508796dc75034b2dee876fe01dc05a08b019f3e5d689ac8842ade2f1befccf5",
5611                                  "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", {});
5612
5613                 // commitment tx with two outputs untrimmed (maximum feerate)
5614                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5615                 chan.feerate_per_kw = 9651180;
5616
5617                 test_commitment!("304402200a8544eba1d216f5c5e530597665fa9bec56943c0f66d98fc3d028df52d84f7002201e45fa5c6bc3a506cc2553e7d1c0043a9811313fc39c954692c0d47cfce2bbd3",
5618                                  "3045022100e11b638c05c650c2f63a421d36ef8756c5ce82f2184278643520311cdf50aa200220259565fb9c8e4a87ccaf17f27a3b9ca4f20625754a0920d9c6c239d8156a11de",
5619                                  "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", {});
5620
5621                 // commitment tx with one output untrimmed (minimum feerate)
5622                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5623                 chan.feerate_per_kw = 9651181;
5624
5625                 test_commitment!("304402202ade0142008309eb376736575ad58d03e5b115499709c6db0b46e36ff394b492022037b63d78d66404d6504d4c4ac13be346f3d1802928a6d3ad95a6a944227161a2",
5626                                  "304402207e8d51e0c570a5868a78414f4e0cbfaed1106b171b9581542c30718ee4eb95ba02203af84194c97adf98898c9afe2f2ed4a7f8dba05a2dfab28ac9d9c604aa49a379",
5627                                  "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", {});
5628
5629                 // commitment tx with fee greater than funder amount
5630                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5631                 chan.feerate_per_kw = 9651936;
5632
5633                 test_commitment!("304402202ade0142008309eb376736575ad58d03e5b115499709c6db0b46e36ff394b492022037b63d78d66404d6504d4c4ac13be346f3d1802928a6d3ad95a6a944227161a2",
5634                                  "304402207e8d51e0c570a5868a78414f4e0cbfaed1106b171b9581542c30718ee4eb95ba02203af84194c97adf98898c9afe2f2ed4a7f8dba05a2dfab28ac9d9c604aa49a379",
5635                                  "02000000000101bef67e4e2fb9ddeeb3461973cd4c62abb35050b1add772995b820b584a488489000000000038b02b8001c0c62d0000000000160014cc1b07838e387deacd0e5232e1e8b49f4c29e484040047304402207e8d51e0c570a5868a78414f4e0cbfaed1106b171b9581542c30718ee4eb95ba02203af84194c97adf98898c9afe2f2ed4a7f8dba05a2dfab28ac9d9c604aa49a3790147304402202ade0142008309eb376736575ad58d03e5b115499709c6db0b46e36ff394b492022037b63d78d66404d6504d4c4ac13be346f3d1802928a6d3ad95a6a944227161a201475221023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb21030e9f7b623d2ccc7c9bd44d66d5ce21ce504c0acf6385a132cec6d3c39fa711c152ae3e195220", {});
5636
5637                 // commitment tx with 3 htlc outputs, 2 offered having the same amount and preimage
5638                 chan.value_to_self_msat = 7_000_000_000 - 2_000_000;
5639                 chan.feerate_per_kw = 253;
5640                 chan.pending_inbound_htlcs.clear();
5641                 chan.pending_inbound_htlcs.push({
5642                         let mut out = InboundHTLCOutput{
5643                                 htlc_id: 1,
5644                                 amount_msat: 2000000,
5645                                 cltv_expiry: 501,
5646                                 payment_hash: PaymentHash([0; 32]),
5647                                 state: InboundHTLCState::Committed,
5648                         };
5649                         out.payment_hash.0 = Sha256::hash(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()).into_inner();
5650                         out
5651                 });
5652                 chan.pending_outbound_htlcs.clear();
5653                 chan.pending_outbound_htlcs.push({
5654                         let mut out = OutboundHTLCOutput{
5655                                 htlc_id: 6,
5656                                 amount_msat: 5000000,
5657                                 cltv_expiry: 506,
5658                                 payment_hash: PaymentHash([0; 32]),
5659                                 state: OutboundHTLCState::Committed,
5660                                 source: HTLCSource::dummy(),
5661                         };
5662                         out.payment_hash.0 = Sha256::hash(&hex::decode("0505050505050505050505050505050505050505050505050505050505050505").unwrap()).into_inner();
5663                         out
5664                 });
5665                 chan.pending_outbound_htlcs.push({
5666                         let mut out = OutboundHTLCOutput{
5667                                 htlc_id: 5,
5668                                 amount_msat: 5000000,
5669                                 cltv_expiry: 505,
5670                                 payment_hash: PaymentHash([0; 32]),
5671                                 state: OutboundHTLCState::Committed,
5672                                 source: HTLCSource::dummy(),
5673                         };
5674                         out.payment_hash.0 = Sha256::hash(&hex::decode("0505050505050505050505050505050505050505050505050505050505050505").unwrap()).into_inner();
5675                         out
5676                 });
5677
5678                 test_commitment!("30440220048705bec5288d28b3f29344b8d124853b1af423a568664d2c6f02c8ea886525022060f998a461052a2476b912db426ea2a06700953a241135c7957f2e79bc222df9",
5679                                  "3045022100c4f1d60b6fca9febc8b39de1a31e84c5f7c4b41c97239ef05f4350aa484c6b5e02200c5134ac8b20eb7a29d0dd4a501f6aa8fefb8489171f4cb408bd2a32324ab03f",
5680                                  "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", {
5681
5682                                   { 0,
5683                                   "304502210081cbb94121761d34c189cd4e6a281feea6f585060ad0ba2632e8d6b3c6bb8a6c02201007981bbd16539d63df2805b5568f1f5688cd2a885d04706f50db9b77ba13c6",
5684                                   "304502210090ed76aeb21b53236a598968abc66e2024691d07b62f53ddbeca8f93144af9c602205f873af5a0c10e62690e9aba09740550f194a9dc455ba4c1c23f6cde7704674c",
5685                                   "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" },
5686                                   { 1,
5687                                   "304402201d0f09d2bf7bc245a4f17980e1e9164290df16c70c6a2ff1592f5030d6108581022061e744a7dc151b36bf0aff7a4f1812ba90b8b03633bb979a270d19858fd960c5",
5688                                   "30450221009aef000d2e843a4202c1b1a2bf554abc9a7902bf49b2cb0759bc507456b7ebad02204e7c3d193ede2fd2b4cd6b39f51a920e581e35575e357e44d7b699c40ce61d39",
5689                                   "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" },
5690                                   { 2,
5691                                   "30440220010bf035d5823596e50dce2076a4d9f942d8d28031c9c428b901a02b6b8140de02203250e8e4a08bc5b4ecdca4d0eedf98223e02e3ac1c0206b3a7ffdb374aa21e5f",
5692                                   "30440220073de0067b88e425b3018b30366bfeda0ccb703118ccd3d02ead08c0f53511d002203fac50ac0e4cf8a3af0b4b1b12e801650591f748f8ddf1e089c160f10b69e511",
5693                                   "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" }
5694                 } );
5695         }
5696
5697         #[test]
5698         fn test_per_commitment_secret_gen() {
5699                 // Test vectors from BOLT 3 Appendix D:
5700
5701                 let mut seed = [0; 32];
5702                 seed[0..32].clone_from_slice(&hex::decode("0000000000000000000000000000000000000000000000000000000000000000").unwrap());
5703                 assert_eq!(chan_utils::build_commitment_secret(&seed, 281474976710655),
5704                            hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap()[..]);
5705
5706                 seed[0..32].clone_from_slice(&hex::decode("FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF").unwrap());
5707                 assert_eq!(chan_utils::build_commitment_secret(&seed, 281474976710655),
5708                            hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap()[..]);
5709
5710                 assert_eq!(chan_utils::build_commitment_secret(&seed, 0xaaaaaaaaaaa),
5711                            hex::decode("56f4008fb007ca9acf0e15b054d5c9fd12ee06cea347914ddbaed70d1c13a528").unwrap()[..]);
5712
5713                 assert_eq!(chan_utils::build_commitment_secret(&seed, 0x555555555555),
5714                            hex::decode("9015daaeb06dba4ccc05b91b2f73bd54405f2be9f217fbacd3c5ac2e62327d31").unwrap()[..]);
5715
5716                 seed[0..32].clone_from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap());
5717                 assert_eq!(chan_utils::build_commitment_secret(&seed, 1),
5718                            hex::decode("915c75942a26bb3a433a8ce2cb0427c29ec6c1775cfc78328b57f6ba7bfeaa9c").unwrap()[..]);
5719         }
5720
5721         #[test]
5722         fn test_key_derivation() {
5723                 // Test vectors from BOLT 3 Appendix E:
5724                 let secp_ctx = Secp256k1::new();
5725
5726                 let base_secret = SecretKey::from_slice(&hex::decode("000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f").unwrap()[..]).unwrap();
5727                 let per_commitment_secret = SecretKey::from_slice(&hex::decode("1f1e1d1c1b1a191817161514131211100f0e0d0c0b0a09080706050403020100").unwrap()[..]).unwrap();
5728
5729                 let base_point = PublicKey::from_secret_key(&secp_ctx, &base_secret);
5730                 assert_eq!(base_point.serialize()[..], hex::decode("036d6caac248af96f6afa7f904f550253a0f3ef3f5aa2fe6838a95b216691468e2").unwrap()[..]);
5731
5732                 let per_commitment_point = PublicKey::from_secret_key(&secp_ctx, &per_commitment_secret);
5733                 assert_eq!(per_commitment_point.serialize()[..], hex::decode("025f7117a78150fe2ef97db7cfc83bd57b2e2c0d0dd25eaf467a4a1c2a45ce1486").unwrap()[..]);
5734
5735                 assert_eq!(chan_utils::derive_public_key(&secp_ctx, &per_commitment_point, &base_point).unwrap().serialize()[..],
5736                                 hex::decode("0235f2dbfaa89b57ec7b055afe29849ef7ddfeb1cefdb9ebdc43f5494984db29e5").unwrap()[..]);
5737
5738                 assert_eq!(chan_utils::derive_private_key(&secp_ctx, &per_commitment_point, &base_secret).unwrap(),
5739                                 SecretKey::from_slice(&hex::decode("cbced912d3b21bf196a766651e436aff192362621ce317704ea2f75d87e7be0f").unwrap()[..]).unwrap());
5740
5741                 assert_eq!(chan_utils::derive_public_revocation_key(&secp_ctx, &per_commitment_point, &base_point).unwrap().serialize()[..],
5742                                 hex::decode("02916e326636d19c33f13e8c0c3a03dd157f332f3e99c317c141dd865eb01f8ff0").unwrap()[..]);
5743
5744                 assert_eq!(chan_utils::derive_private_revocation_key(&secp_ctx, &per_commitment_secret, &base_secret).unwrap(),
5745                                 SecretKey::from_slice(&hex::decode("d09ffff62ddb2297ab000cc85bcb4283fdeb6aa052affbc9dddcf33b61078110").unwrap()[..]).unwrap());
5746         }
5747 }