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

   1 use bitcoin::blockdata::block::BlockHeader;
   2 use bitcoin::blockdata::script::{Script,Builder};
   3 use bitcoin::blockdata::transaction::{TxIn, TxOut, Transaction, SigHashType};
   4 use bitcoin::blockdata::opcodes;
   5 use bitcoin::util::hash::BitcoinHash;
   6 use bitcoin::util::bip143;
   7 use bitcoin::consensus::encode::{self, Encodable, Decodable};
   8
   9 use bitcoin_hashes::{Hash, HashEngine};
  10 use bitcoin_hashes::sha256::Hash as Sha256;
  11 use bitcoin_hashes::hash160::Hash as Hash160;
  12 use bitcoin_hashes::sha256d::Hash as Sha256dHash;
  13
  14 use secp256k1::key::{PublicKey,SecretKey};
  15 use secp256k1::{Secp256k1,Signature};
  16 use secp256k1;
  17
  18 use ln::msgs;
  19 use ln::msgs::{DecodeError, OptionalField};
  20 use ln::channelmonitor::ChannelMonitor;
  21 use ln::channelmanager::{PendingHTLCStatus, HTLCSource, HTLCFailReason, HTLCFailureMsg, PendingForwardHTLCInfo, RAACommitmentOrder, PaymentPreimage, PaymentHash};
  22 use ln::chan_utils::{TxCreationKeys,HTLCOutputInCommitment,HTLC_SUCCESS_TX_WEIGHT,HTLC_TIMEOUT_TX_WEIGHT};
  23 use ln::chan_utils;
  24 use chain::chaininterface::{FeeEstimator,ConfirmationTarget};
  25 use chain::transaction::OutPoint;
  26 use chain::keysinterface::{ChannelKeys, KeysInterface};
  27 use util::transaction_utils;
  28 use util::ser::{Readable, ReadableArgs, Writeable, Writer, WriterWriteAdaptor};
  29 use util::logger::{Logger, LogHolder};
  30 use util::errors::APIError;
  31 use util::config::{UserConfig,ChannelConfig};
  32
  33 use std;
  34 use std::default::Default;
  35 use std::{cmp,mem};
  36 use std::time::Instant;
  37 use std::sync::{Arc};
  38
  39 #[cfg(test)]
  40 pub struct ChannelValueStat {
  41         pub value_to_self_msat: u64,
  42         pub channel_value_msat: u64,
  43         pub channel_reserve_msat: u64,
  44         pub pending_outbound_htlcs_amount_msat: u64,
  45         pub pending_inbound_htlcs_amount_msat: u64,
  46         pub holding_cell_outbound_amount_msat: u64,
  47         pub their_max_htlc_value_in_flight_msat: u64, // outgoing
  48 }
  49
  50 enum InboundHTLCRemovalReason {
  51         FailRelay(msgs::OnionErrorPacket),
  52         FailMalformed(([u8; 32], u16)),
  53         Fulfill(PaymentPreimage),
  54 }
  55
  56 enum InboundHTLCState {
  57         /// Added by remote, to be included in next local commitment tx.
  58         RemoteAnnounced(PendingHTLCStatus),
  59         /// Included in a received commitment_signed message (implying we've revoke_and_ack'ed it), but
  60         /// the remote side hasn't yet revoked their previous state, which we need them to do before we
  61         /// accept this HTLC. Implies AwaitingRemoteRevoke.
  62         /// We also have not yet included this HTLC in a commitment_signed message, and are waiting on
  63         /// a remote revoke_and_ack on a previous state before we can do so.
  64         AwaitingRemoteRevokeToAnnounce(PendingHTLCStatus),
  65         /// Included in a received commitment_signed message (implying we've revoke_and_ack'ed it), but
  66         /// the remote side hasn't yet revoked their previous state, which we need them to do before we
  67         /// accept this HTLC. Implies AwaitingRemoteRevoke.
  68         /// We have included this HTLC in our latest commitment_signed and are now just waiting on a
  69         /// revoke_and_ack.
  70         AwaitingAnnouncedRemoteRevoke(PendingHTLCStatus),
  71         Committed,
  72         /// Removed by us and a new commitment_signed was sent (if we were AwaitingRemoteRevoke when we
  73         /// created it we would have put it in the holding cell instead). When they next revoke_and_ack
  74         /// we'll drop it.
  75         /// Note that we have to keep an eye on the HTLC until we've received a broadcastable
  76         /// commitment transaction without it as otherwise we'll have to force-close the channel to
  77         /// claim it before the timeout (obviously doesn't apply to revoked HTLCs that we can't claim
  78         /// anyway). That said, ChannelMonitor does this for us (see
  79         /// ChannelMonitor::would_broadcast_at_height) so we actually remove the HTLC from our own
  80         /// local state before then, once we're sure that the next commitment_signed and
  81         /// ChannelMonitor::provide_latest_local_commitment_tx_info will not include this HTLC.
  82         LocalRemoved(InboundHTLCRemovalReason),
  83 }
  84
  85 struct InboundHTLCOutput {
  86         htlc_id: u64,
  87         amount_msat: u64,
  88         cltv_expiry: u32,
  89         payment_hash: PaymentHash,
  90         state: InboundHTLCState,
  91 }
  92
  93 enum OutboundHTLCState {
  94         /// Added by us and included in a commitment_signed (if we were AwaitingRemoteRevoke when we
  95         /// created it we would have put it in the holding cell instead). When they next revoke_and_ack
  96         /// we will promote to Committed (note that they may not accept it until the next time we
  97         /// revoke, but we don't really care about that:
  98         ///  * they've revoked, so worst case we can announce an old state and get our (option on)
  99         ///    money back (though we won't), and,
 100         ///  * we'll send them a revoke when they send a commitment_signed, and since only they're
 101         ///    allowed to remove it, the "can only be removed once committed on both sides" requirement
 102         ///    doesn't matter to us and it's up to them to enforce it, worst-case they jump ahead but
 103         ///    we'll never get out of sync).
 104         /// Note that we Box the OnionPacket as it's rather large and we don't want to blow up
 105         /// OutboundHTLCOutput's size just for a temporary bit
 106         LocalAnnounced(Box<msgs::OnionPacket>),
 107         Committed,
 108         /// Remote removed this (outbound) HTLC. We're waiting on their commitment_signed to finalize
 109         /// the change (though they'll need to revoke before we fail the payment).
 110         RemoteRemoved(Option<HTLCFailReason>),
 111         /// Remote removed this and sent a commitment_signed (implying we've revoke_and_ack'ed it), but
 112         /// the remote side hasn't yet revoked their previous state, which we need them to do before we
 113         /// can do any backwards failing. Implies AwaitingRemoteRevoke.
 114         /// We also have not yet removed this HTLC in a commitment_signed message, and are waiting on a
 115         /// remote revoke_and_ack on a previous state before we can do so.
 116         AwaitingRemoteRevokeToRemove(Option<HTLCFailReason>),
 117         /// Remote removed this and sent a commitment_signed (implying we've revoke_and_ack'ed it), but
 118         /// the remote side hasn't yet revoked their previous state, which we need them to do before we
 119         /// can do any backwards failing. Implies AwaitingRemoteRevoke.
 120         /// We have removed this HTLC in our latest commitment_signed and are now just waiting on a
 121         /// revoke_and_ack to drop completely.
 122         AwaitingRemovedRemoteRevoke(Option<HTLCFailReason>),
 123 }
 124
 125 struct OutboundHTLCOutput {
 126         htlc_id: u64,
 127         amount_msat: u64,
 128         cltv_expiry: u32,
 129         payment_hash: PaymentHash,
 130         state: OutboundHTLCState,
 131         source: HTLCSource,
 132 }
 133
 134 /// See AwaitingRemoteRevoke ChannelState for more info
 135 enum HTLCUpdateAwaitingACK {
 136         AddHTLC {
 137                 // always outbound
 138                 amount_msat: u64,
 139                 cltv_expiry: u32,
 140                 payment_hash: PaymentHash,
 141                 source: HTLCSource,
 142                 onion_routing_packet: msgs::OnionPacket,
 143                 time_created: Instant, //TODO: Some kind of timeout thing-a-majig
 144         },
 145         ClaimHTLC {
 146                 payment_preimage: PaymentPreimage,
 147                 htlc_id: u64,
 148         },
 149         FailHTLC {
 150                 htlc_id: u64,
 151                 err_packet: msgs::OnionErrorPacket,
 152         },
 153 }
 154
 155 /// There are a few "states" and then a number of flags which can be applied:
 156 /// We first move through init with OurInitSent -> TheirInitSent -> FundingCreated -> FundingSent.
 157 /// TheirFundingLocked and OurFundingLocked then get set on FundingSent, and when both are set we
 158 /// move on to ChannelFunded.
 159 /// Note that PeerDisconnected can be set on both ChannelFunded and FundingSent.
 160 /// ChannelFunded can then get all remaining flags set on it, until we finish shutdown, then we
 161 /// move on to ShutdownComplete, at which point most calls into this channel are disallowed.
 162 enum ChannelState {
 163         /// Implies we have (or are prepared to) send our open_channel/accept_channel message
 164         OurInitSent = (1 << 0),
 165         /// Implies we have received their open_channel/accept_channel message
 166         TheirInitSent = (1 << 1),
 167         /// We have sent funding_created and are awaiting a funding_signed to advance to FundingSent.
 168         /// Note that this is nonsense for an inbound channel as we immediately generate funding_signed
 169         /// upon receipt of funding_created, so simply skip this state.
 170         FundingCreated = 4,
 171         /// Set when we have received/sent funding_created and funding_signed and are thus now waiting
 172         /// on the funding transaction to confirm. The FundingLocked flags are set to indicate when we
 173         /// and our counterparty consider the funding transaction confirmed.
 174         FundingSent = 8,
 175         /// Flag which can be set on FundingSent to indicate they sent us a funding_locked message.
 176         /// Once both TheirFundingLocked and OurFundingLocked are set, state moves on to ChannelFunded.
 177         TheirFundingLocked = (1 << 4),
 178         /// Flag which can be set on FundingSent to indicate we sent them a funding_locked message.
 179         /// Once both TheirFundingLocked and OurFundingLocked are set, state moves on to ChannelFunded.
 180         OurFundingLocked = (1 << 5),
 181         ChannelFunded = 64,
 182         /// Flag which is set on ChannelFunded and FundingSent indicating remote side is considered
 183         /// "disconnected" and no updates are allowed until after we've done a channel_reestablish
 184         /// dance.
 185         PeerDisconnected = (1 << 7),
 186         /// Flag which is set on ChannelFunded and FundingSent indicating the user has told us they
 187         /// failed to update our ChannelMonitor somewhere and we should pause sending any outbound
 188         /// messages until they've managed to do so.
 189         MonitorUpdateFailed = (1 << 8),
 190         /// Flag which implies that we have sent a commitment_signed but are awaiting the responding
 191         /// revoke_and_ack message. During this time period, we can't generate new commitment_signed
 192         /// messages as then we will be unable to determine which HTLCs they included in their
 193         /// revoke_and_ack implicit ACK, so instead we have to hold them away temporarily to be sent
 194         /// later.
 195         /// Flag is set on ChannelFunded.
 196         AwaitingRemoteRevoke = (1 << 9),
 197         /// Flag which is set on ChannelFunded or FundingSent after receiving a shutdown message from
 198         /// the remote end. If set, they may not add any new HTLCs to the channel, and we are expected
 199         /// to respond with our own shutdown message when possible.
 200         RemoteShutdownSent = (1 << 10),
 201         /// Flag which is set on ChannelFunded or FundingSent after sending a shutdown message. At this
 202         /// point, we may not add any new HTLCs to the channel.
 203         /// TODO: Investigate some kind of timeout mechanism by which point the remote end must provide
 204         /// us their shutdown.
 205         LocalShutdownSent = (1 << 11),
 206         /// We've successfully negotiated a closing_signed dance. At this point ChannelManager is about
 207         /// to drop us, but we store this anyway.
 208         ShutdownComplete = 4096,
 209 }
 210 const BOTH_SIDES_SHUTDOWN_MASK: u32 = (ChannelState::LocalShutdownSent as u32 | ChannelState::RemoteShutdownSent as u32);
 211 const MULTI_STATE_FLAGS: u32 = (BOTH_SIDES_SHUTDOWN_MASK | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32);
 212
 213 const INITIAL_COMMITMENT_NUMBER: u64 = (1 << 48) - 1;
 214
 215 // TODO: We should refactor this to be an Inbound/OutboundChannel until initial setup handshaking
 216 // has been completed, and then turn into a Channel to get compiler-time enforcement of things like
 217 // calling channel_id() before we're set up or things like get_outbound_funding_signed on an
 218 // inbound channel.
 219 pub(super) struct Channel {
 220         config: ChannelConfig,
 221
 222         user_id: u64,
 223
 224         channel_id: [u8; 32],
 225         channel_state: u32,
 226         channel_outbound: bool,
 227         secp_ctx: Secp256k1<secp256k1::All>,
 228         channel_value_satoshis: u64,
 229
 230         local_keys: ChannelKeys,
 231         shutdown_pubkey: PublicKey,
 232
 233         // Our commitment numbers start at 2^48-1 and count down, whereas the ones used in transaction
 234         // generation start at 0 and count up...this simplifies some parts of implementation at the
 235         // cost of others, but should really just be changed.
 236
 237         cur_local_commitment_transaction_number: u64,
 238         cur_remote_commitment_transaction_number: u64,
 239         value_to_self_msat: u64, // Excluding all pending_htlcs, excluding fees
 240         /// Upon receipt of a channel_reestablish we have to figure out whether to send a
 241         /// revoke_and_ack first or a commitment update first. Generally, we prefer to send
 242         /// revoke_and_ack first, but if we had a pending commitment update of our own waiting on a
 243         /// remote revoke when we received the latest commitment update from the remote we have to make
 244         /// sure that commitment update gets resent first.
 245         received_commitment_while_awaiting_raa: bool,
 246         pending_inbound_htlcs: Vec<InboundHTLCOutput>,
 247         pending_outbound_htlcs: Vec<OutboundHTLCOutput>,
 248         holding_cell_htlc_updates: Vec<HTLCUpdateAwaitingACK>,
 249
 250         monitor_pending_revoke_and_ack: bool,
 251         monitor_pending_commitment_signed: bool,
 252         monitor_pending_order: Option<RAACommitmentOrder>,
 253         monitor_pending_forwards: Vec<(PendingForwardHTLCInfo, u64)>,
 254         monitor_pending_failures: Vec<(HTLCSource, PaymentHash, HTLCFailReason)>,
 255
 256         // pending_update_fee is filled when sending and receiving update_fee
 257         // For outbound channel, feerate_per_kw is updated with the value from
 258         // pending_update_fee when revoke_and_ack is received
 259         //
 260         // For inbound channel, feerate_per_kw is updated when it receives
 261         // commitment_signed and revoke_and_ack is generated
 262         // The pending value is kept when another pair of update_fee and commitment_signed
 263         // is received during AwaitingRemoteRevoke and relieved when the expected
 264         // revoke_and_ack is received and new commitment_signed is generated to be
 265         // sent to the funder. Otherwise, the pending value is removed when receiving
 266         // commitment_signed.
 267         pending_update_fee: Option<u64>,
 268         // update_fee() during ChannelState::AwaitingRemoteRevoke is hold in
 269         // holdina_cell_update_fee then moved to pending_udpate_fee when revoke_and_ack
 270         // is received. holding_cell_update_fee is updated when there are additional
 271         // update_fee() during ChannelState::AwaitingRemoteRevoke.
 272         holding_cell_update_fee: Option<u64>,
 273         next_local_htlc_id: u64,
 274         next_remote_htlc_id: u64,
 275         channel_update_count: u32,
 276         feerate_per_kw: u64,
 277
 278         #[cfg(debug_assertions)]
 279         /// Max to_local and to_remote outputs in a locally-generated commitment transaction
 280         max_commitment_tx_output_local: ::std::sync::Mutex<(u64, u64)>,
 281         #[cfg(debug_assertions)]
 282         /// Max to_local and to_remote outputs in a remote-generated commitment transaction
 283         max_commitment_tx_output_remote: ::std::sync::Mutex<(u64, u64)>,
 284
 285         #[cfg(test)]
 286         // Used in ChannelManager's tests to send a revoked transaction
 287         pub last_local_commitment_txn: Vec<Transaction>,
 288         #[cfg(not(test))]
 289         last_local_commitment_txn: Vec<Transaction>,
 290
 291         last_sent_closing_fee: Option<(u64, u64)>, // (feerate, fee)
 292
 293         /// The hash of the block in which the funding transaction reached our CONF_TARGET. We use this
 294         /// to detect unconfirmation after a serialize-unserialize roundtrip where we may not see a full
 295         /// series of block_connected/block_disconnected calls. Obviously this is not a guarantee as we
 296         /// could miss the funding_tx_confirmed_in block as well, but it serves as a useful fallback.
 297         funding_tx_confirmed_in: Option<Sha256dHash>,
 298         short_channel_id: Option<u64>,
 299         /// Used to deduplicate block_connected callbacks, also used to verify consistency during
 300         /// ChannelManager deserialization (hence pub(super))
 301         pub(super) last_block_connected: Sha256dHash,
 302         funding_tx_confirmations: u64,
 303
 304         their_dust_limit_satoshis: u64,
 305         #[cfg(test)]
 306         pub(super) our_dust_limit_satoshis: u64,
 307         #[cfg(not(test))]
 308         our_dust_limit_satoshis: u64,
 309         #[cfg(test)]
 310         pub(super) their_max_htlc_value_in_flight_msat: u64,
 311         #[cfg(not(test))]
 312         their_max_htlc_value_in_flight_msat: u64,
 313         //get_our_max_htlc_value_in_flight_msat(): u64,
 314         /// minimum channel reserve for **self** to maintain - set by them.
 315         their_channel_reserve_satoshis: u64,
 316         //get_our_channel_reserve_satoshis(): u64,
 317         their_htlc_minimum_msat: u64,
 318         our_htlc_minimum_msat: u64,
 319         their_to_self_delay: u16,
 320         //implied by BREAKDOWN_TIMEOUT: our_to_self_delay: u16,
 321         #[cfg(test)]
 322         pub their_max_accepted_htlcs: u16,
 323         #[cfg(not(test))]
 324         their_max_accepted_htlcs: u16,
 325         //implied by OUR_MAX_HTLCS: our_max_accepted_htlcs: u16,
 326         minimum_depth: u32,
 327
 328         their_funding_pubkey: Option<PublicKey>,
 329         their_revocation_basepoint: Option<PublicKey>,
 330         their_payment_basepoint: Option<PublicKey>,
 331         their_delayed_payment_basepoint: Option<PublicKey>,
 332         their_htlc_basepoint: Option<PublicKey>,
 333         their_cur_commitment_point: Option<PublicKey>,
 334
 335         their_prev_commitment_point: Option<PublicKey>,
 336         their_node_id: PublicKey,
 337
 338         their_shutdown_scriptpubkey: Option<Script>,
 339
 340         channel_monitor: ChannelMonitor,
 341
 342         logger: Arc<Logger>,
 343 }
 344
 345 pub const OUR_MAX_HTLCS: u16 = 50; //TODO
 346 /// Confirmation count threshold at which we close a channel. Ideally we'd keep the channel around
 347 /// on ice until the funding transaction gets more confirmations, but the LN protocol doesn't
 348 /// really allow for this, so instead we're stuck closing it out at that point.
 349 const UNCONF_THRESHOLD: u32 = 6;
 350 /// The amount of time we require our counterparty wait to claim their money (ie time between when
 351 /// we, or our watchtower, must check for them having broadcast a theft transaction).
 352 #[cfg(not(test))]
 353 const BREAKDOWN_TIMEOUT: u16 = 6 * 24 * 7; //TODO?
 354 #[cfg(test)]
 355 pub const BREAKDOWN_TIMEOUT: u16 = 6 * 24 * 7; //TODO?
 356 /// The amount of time we're willing to wait to claim money back to us
 357 const MAX_LOCAL_BREAKDOWN_TIMEOUT: u16 = 6 * 24 * 14;
 358 /// Exposing these two constants for use in test in ChannelMonitor
 359 pub const COMMITMENT_TX_BASE_WEIGHT: u64 = 724;
 360 pub const COMMITMENT_TX_WEIGHT_PER_HTLC: u64 = 172;
 361 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
 362 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?)
 363 /// Maximmum `funding_satoshis` value, according to the BOLT #2 specification
 364 /// it's 2^24.
 365 pub const MAX_FUNDING_SATOSHIS: u64 = (1 << 24);
 366
 367 #[cfg(test)]
 368 pub const ACCEPTED_HTLC_SCRIPT_WEIGHT: usize = 138; //Here we have a diff due to HTLC CLTV expiry being < 2^15 in test
 369 #[cfg(not(test))]
 370 pub const ACCEPTED_HTLC_SCRIPT_WEIGHT: usize = 139;
 371 pub const OFFERED_HTLC_SCRIPT_WEIGHT: usize = 133;
 372
 373 /// Used to return a simple Error back to ChannelManager. Will get converted to a
 374 /// msgs::ErrorAction::SendErrorMessage or msgs::ErrorAction::IgnoreError as appropriate with our
 375 /// channel_id in ChannelManager.
 376 #[derive(Debug)]
 377 pub(super) enum ChannelError {
 378         Ignore(&'static str),
 379         Close(&'static str),
 380 }
 381
 382 macro_rules! secp_check {
 383         ($res: expr, $err: expr) => {
 384                 match $res {
 385                         Ok(thing) => thing,
 386                         Err(_) => return Err(ChannelError::Close($err)),
 387                 }
 388         };
 389 }
 390
 391 impl Channel {
 392         // Convert constants + channel value to limits:
 393         fn get_our_max_htlc_value_in_flight_msat(channel_value_satoshis: u64) -> u64 {
 394                 channel_value_satoshis * 1000 / 10 //TODO
 395         }
 396
 397         /// Returns a minimum channel reserve value **they** need to maintain
 398         ///
 399         /// Guaranteed to return a value no larger than channel_value_satoshis
 400         fn get_our_channel_reserve_satoshis(channel_value_satoshis: u64) -> u64 {
 401                 let (q, _) = channel_value_satoshis.overflowing_div(100);
 402                 cmp::min(channel_value_satoshis, cmp::max(q, 1000)) //TODO
 403         }
 404
 405         fn derive_our_dust_limit_satoshis(at_open_background_feerate: u64) -> u64 {
 406                 cmp::max(at_open_background_feerate * B_OUTPUT_PLUS_SPENDING_INPUT_WEIGHT / 1000, 546) //TODO
 407         }
 408
 409         fn derive_our_htlc_minimum_msat(_at_open_channel_feerate_per_kw: u64) -> u64 {
 410                 1000 // TODO
 411         }
 412
 413         fn derive_minimum_depth(_channel_value_satoshis_msat: u64, _value_to_self_msat: u64) -> u32 {
 414                 // Note that in order to comply with BOLT 7 announcement_signatures requirements this must
 415                 // be at least 6.
 416                 const CONF_TARGET: u32 = 12; //TODO: Should be much higher
 417                 CONF_TARGET
 418         }
 419
 420         // Constructors:
 421         pub fn new_outbound(fee_estimator: &FeeEstimator, keys_provider: &Arc<KeysInterface>, their_node_id: PublicKey, channel_value_satoshis: u64, push_msat: u64, user_id: u64, logger: Arc<Logger>, config: &UserConfig) -> Result<Channel, APIError> {
 422                 let chan_keys = keys_provider.get_channel_keys(false);
 423
 424                 if channel_value_satoshis >= MAX_FUNDING_SATOSHIS {
 425                         return Err(APIError::APIMisuseError{err: "funding value > 2^24"});
 426                 }
 427
 428                 if push_msat > channel_value_satoshis * 1000 {
 429                         return Err(APIError::APIMisuseError{err: "push value > channel value"});
 430                 }
 431
 432
 433                 let background_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background);
 434                 if Channel::get_our_channel_reserve_satoshis(channel_value_satoshis) < Channel::derive_our_dust_limit_satoshis(background_feerate) {
 435                         return Err(APIError::FeeRateTooHigh{err: format!("Not enough reserve above dust limit can be found at current fee rate({})", background_feerate), feerate: background_feerate});
 436                 }
 437
 438                 let feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Normal);
 439
 440                 let secp_ctx = Secp256k1::new();
 441                 let channel_monitor = ChannelMonitor::new(&chan_keys.revocation_base_key, &chan_keys.delayed_payment_base_key,
 442                                                           &chan_keys.htlc_base_key, &chan_keys.payment_base_key, &keys_provider.get_shutdown_pubkey(), BREAKDOWN_TIMEOUT,
 443                                                           keys_provider.get_destination_script(), logger.clone());
 444
 445                 Ok(Channel {
 446                         user_id: user_id,
 447                         config: config.channel_options.clone(),
 448
 449                         channel_id: keys_provider.get_channel_id(),
 450                         channel_state: ChannelState::OurInitSent as u32,
 451                         channel_outbound: true,
 452                         secp_ctx: secp_ctx,
 453                         channel_value_satoshis: channel_value_satoshis,
 454
 455                         local_keys: chan_keys,
 456                         shutdown_pubkey: keys_provider.get_shutdown_pubkey(),
 457                         cur_local_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
 458                         cur_remote_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
 459                         value_to_self_msat: channel_value_satoshis * 1000 - push_msat,
 460                         received_commitment_while_awaiting_raa: false,
 461
 462                         pending_inbound_htlcs: Vec::new(),
 463                         pending_outbound_htlcs: Vec::new(),
 464                         holding_cell_htlc_updates: Vec::new(),
 465                         pending_update_fee: None,
 466                         holding_cell_update_fee: None,
 467                         next_local_htlc_id: 0,
 468                         next_remote_htlc_id: 0,
 469                         channel_update_count: 1,
 470
 471                         monitor_pending_revoke_and_ack: false,
 472                         monitor_pending_commitment_signed: false,
 473                         monitor_pending_order: None,
 474                         monitor_pending_forwards: Vec::new(),
 475                         monitor_pending_failures: Vec::new(),
 476
 477                         #[cfg(debug_assertions)]
 478                         max_commitment_tx_output_local: ::std::sync::Mutex::new((channel_value_satoshis * 1000 - push_msat, push_msat)),
 479                         #[cfg(debug_assertions)]
 480                         max_commitment_tx_output_remote: ::std::sync::Mutex::new((channel_value_satoshis * 1000 - push_msat, push_msat)),
 481
 482                         last_local_commitment_txn: Vec::new(),
 483
 484                         last_sent_closing_fee: None,
 485
 486                         funding_tx_confirmed_in: None,
 487                         short_channel_id: None,
 488                         last_block_connected: Default::default(),
 489                         funding_tx_confirmations: 0,
 490
 491                         feerate_per_kw: feerate,
 492                         their_dust_limit_satoshis: 0,
 493                         our_dust_limit_satoshis: Channel::derive_our_dust_limit_satoshis(background_feerate),
 494                         their_max_htlc_value_in_flight_msat: 0,
 495                         their_channel_reserve_satoshis: 0,
 496                         their_htlc_minimum_msat: 0,
 497                         our_htlc_minimum_msat: Channel::derive_our_htlc_minimum_msat(feerate),
 498                         their_to_self_delay: 0,
 499                         their_max_accepted_htlcs: 0,
 500                         minimum_depth: 0, // Filled in in accept_channel
 501
 502                         their_funding_pubkey: None,
 503                         their_revocation_basepoint: None,
 504                         their_payment_basepoint: None,
 505                         their_delayed_payment_basepoint: None,
 506                         their_htlc_basepoint: None,
 507                         their_cur_commitment_point: None,
 508
 509                         their_prev_commitment_point: None,
 510                         their_node_id: their_node_id,
 511
 512                         their_shutdown_scriptpubkey: None,
 513
 514                         channel_monitor: channel_monitor,
 515
 516                         logger,
 517                 })
 518         }
 519
 520         fn check_remote_fee(fee_estimator: &FeeEstimator, feerate_per_kw: u32) -> Result<(), ChannelError> {
 521                 if (feerate_per_kw as u64) < fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background) {
 522                         return Err(ChannelError::Close("Peer's feerate much too low"));
 523                 }
 524                 if (feerate_per_kw as u64) > fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::HighPriority) * 2 {
 525                         return Err(ChannelError::Close("Peer's feerate much too high"));
 526                 }
 527                 Ok(())
 528         }
 529
 530         /// Creates a new channel from a remote sides' request for one.
 531         /// Assumes chain_hash has already been checked and corresponds with what we expect!
 532         pub fn new_from_req(fee_estimator: &FeeEstimator, keys_provider: &Arc<KeysInterface>, their_node_id: PublicKey, msg: &msgs::OpenChannel, user_id: u64, logger: Arc<Logger>, config: &UserConfig) -> Result<Channel, ChannelError> {
 533                 let chan_keys = keys_provider.get_channel_keys(true);
 534                 let mut local_config = (*config).channel_options.clone();
 535
 536                 // Check sanity of message fields:
 537                 if msg.funding_satoshis >= MAX_FUNDING_SATOSHIS {
 538                         return Err(ChannelError::Close("funding value > 2^24"));
 539                 }
 540                 if msg.channel_reserve_satoshis > msg.funding_satoshis {
 541                         return Err(ChannelError::Close("Bogus channel_reserve_satoshis"));
 542                 }
 543                 if msg.push_msat > (msg.funding_satoshis - msg.channel_reserve_satoshis) * 1000 {
 544                         return Err(ChannelError::Close("push_msat larger than funding value"));
 545                 }
 546                 if msg.dust_limit_satoshis > msg.funding_satoshis {
 547                         return Err(ChannelError::Close("Peer never wants payout outputs?"));
 548                 }
 549                 if msg.dust_limit_satoshis > msg.channel_reserve_satoshis {
 550                         return Err(ChannelError::Close("Bogus; channel reserve is less than dust limit"));
 551                 }
 552                 if msg.htlc_minimum_msat >= (msg.funding_satoshis - msg.channel_reserve_satoshis) * 1000 {
 553                         return Err(ChannelError::Close("Minimum htlc value is full channel value"));
 554                 }
 555                 Channel::check_remote_fee(fee_estimator, msg.feerate_per_kw)?;
 556
 557                 if msg.to_self_delay > MAX_LOCAL_BREAKDOWN_TIMEOUT {
 558                         return Err(ChannelError::Close("They wanted our payments to be delayed by a needlessly long period"));
 559                 }
 560                 if msg.max_accepted_htlcs < 1 {
 561                         return Err(ChannelError::Close("0 max_accpted_htlcs makes for a useless channel"));
 562                 }
 563                 if msg.max_accepted_htlcs > 483 {
 564                         return Err(ChannelError::Close("max_accpted_htlcs > 483"));
 565                 }
 566
 567                 // Now check against optional parameters as set by config...
 568                 if msg.funding_satoshis < config.channel_limits.min_funding_satoshis {
 569                         return Err(ChannelError::Close("funding satoshis is less than the user specified limit"));
 570                 }
 571                 if msg.htlc_minimum_msat > config.channel_limits.max_htlc_minimum_msat {
 572                         return Err(ChannelError::Close("htlc minimum msat is higher than the user specified limit"));
 573                 }
 574                 if msg.max_htlc_value_in_flight_msat < config.channel_limits.min_max_htlc_value_in_flight_msat {
 575                         return Err(ChannelError::Close("max htlc value in flight msat is less than the user specified limit"));
 576                 }
 577                 if msg.channel_reserve_satoshis > config.channel_limits.max_channel_reserve_satoshis {
 578                         return Err(ChannelError::Close("channel reserve satoshis is higher than the user specified limit"));
 579                 }
 580                 if msg.max_accepted_htlcs < config.channel_limits.min_max_accepted_htlcs {
 581                         return Err(ChannelError::Close("max accepted htlcs is less than the user specified limit"));
 582                 }
 583                 if msg.dust_limit_satoshis < config.channel_limits.min_dust_limit_satoshis {
 584                         return Err(ChannelError::Close("dust limit satoshis is less than the user specified limit"));
 585                 }
 586                 if msg.dust_limit_satoshis > config.channel_limits.max_dust_limit_satoshis {
 587                         return Err(ChannelError::Close("dust limit satoshis is greater than the user specified limit"));
 588                 }
 589
 590                 // Convert things into internal flags and prep our state:
 591
 592                 let their_announce = if (msg.channel_flags & 1) == 1 { true } else { false };
 593                 if config.channel_limits.force_announced_channel_preference {
 594                         if local_config.announced_channel != their_announce {
 595                                 return Err(ChannelError::Close("Peer tried to open channel but their announcement preference is different from ours"));
 596                         }
 597                 }
 598                 // we either accept their preference or the preferences match
 599                 local_config.announced_channel = their_announce;
 600
 601                 let background_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background);
 602
 603                 let our_dust_limit_satoshis = Channel::derive_our_dust_limit_satoshis(background_feerate);
 604                 let our_channel_reserve_satoshis = Channel::get_our_channel_reserve_satoshis(msg.funding_satoshis);
 605                 if our_channel_reserve_satoshis < our_dust_limit_satoshis {
 606                         return Err(ChannelError::Close("Suitable channel reserve not found. aborting"));
 607                 }
 608                 if msg.channel_reserve_satoshis < our_dust_limit_satoshis {
 609                         return Err(ChannelError::Close("channel_reserve_satoshis too small"));
 610                 }
 611                 if our_channel_reserve_satoshis < msg.dust_limit_satoshis {
 612                         return Err(ChannelError::Close("Dust limit too high for our channel reserve"));
 613                 }
 614
 615                 // check if the funder's amount for the initial commitment tx is sufficient
 616                 // for full fee payment
 617                 let funders_amount_msat = msg.funding_satoshis * 1000 - msg.push_msat;
 618                 if funders_amount_msat < background_feerate * COMMITMENT_TX_BASE_WEIGHT {
 619                         return Err(ChannelError::Close("Insufficient funding amount for initial commitment"));
 620                 }
 621
 622                 let to_local_msat = msg.push_msat;
 623                 let to_remote_msat = funders_amount_msat - background_feerate * COMMITMENT_TX_BASE_WEIGHT;
 624                 if to_local_msat <= msg.channel_reserve_satoshis * 1000 && to_remote_msat <= our_channel_reserve_satoshis * 1000 {
 625                         return Err(ChannelError::Close("Insufficient funding amount for initial commitment"));
 626                 }
 627
 628                 let secp_ctx = Secp256k1::new();
 629                 let mut channel_monitor = ChannelMonitor::new(&chan_keys.revocation_base_key, &chan_keys.delayed_payment_base_key,
 630                                                               &chan_keys.htlc_base_key, &chan_keys.payment_base_key, &keys_provider.get_shutdown_pubkey(), BREAKDOWN_TIMEOUT,
 631                                                               keys_provider.get_destination_script(), logger.clone());
 632                 channel_monitor.set_their_base_keys(&msg.htlc_basepoint, &msg.delayed_payment_basepoint);
 633                 channel_monitor.set_their_to_self_delay(msg.to_self_delay);
 634
 635                 let mut chan = Channel {
 636                         user_id: user_id,
 637                         config: local_config,
 638
 639                         channel_id: msg.temporary_channel_id,
 640                         channel_state: (ChannelState::OurInitSent as u32) | (ChannelState::TheirInitSent as u32),
 641                         channel_outbound: false,
 642                         secp_ctx: secp_ctx,
 643
 644                         local_keys: chan_keys,
 645                         shutdown_pubkey: keys_provider.get_shutdown_pubkey(),
 646                         cur_local_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
 647                         cur_remote_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
 648                         value_to_self_msat: msg.push_msat,
 649                         received_commitment_while_awaiting_raa: false,
 650
 651                         pending_inbound_htlcs: Vec::new(),
 652                         pending_outbound_htlcs: Vec::new(),
 653                         holding_cell_htlc_updates: Vec::new(),
 654                         pending_update_fee: None,
 655                         holding_cell_update_fee: None,
 656                         next_local_htlc_id: 0,
 657                         next_remote_htlc_id: 0,
 658                         channel_update_count: 1,
 659
 660                         monitor_pending_revoke_and_ack: false,
 661                         monitor_pending_commitment_signed: false,
 662                         monitor_pending_order: None,
 663                         monitor_pending_forwards: Vec::new(),
 664                         monitor_pending_failures: Vec::new(),
 665
 666                         #[cfg(debug_assertions)]
 667                         max_commitment_tx_output_local: ::std::sync::Mutex::new((msg.push_msat, msg.funding_satoshis * 1000 - msg.push_msat)),
 668                         #[cfg(debug_assertions)]
 669                         max_commitment_tx_output_remote: ::std::sync::Mutex::new((msg.push_msat, msg.funding_satoshis * 1000 - msg.push_msat)),
 670
 671                         last_local_commitment_txn: Vec::new(),
 672
 673                         last_sent_closing_fee: None,
 674
 675                         funding_tx_confirmed_in: None,
 676                         short_channel_id: None,
 677                         last_block_connected: Default::default(),
 678                         funding_tx_confirmations: 0,
 679
 680                         feerate_per_kw: msg.feerate_per_kw as u64,
 681                         channel_value_satoshis: msg.funding_satoshis,
 682                         their_dust_limit_satoshis: msg.dust_limit_satoshis,
 683                         our_dust_limit_satoshis: our_dust_limit_satoshis,
 684                         their_max_htlc_value_in_flight_msat: cmp::min(msg.max_htlc_value_in_flight_msat, msg.funding_satoshis * 1000),
 685                         their_channel_reserve_satoshis: msg.channel_reserve_satoshis,
 686                         their_htlc_minimum_msat: msg.htlc_minimum_msat,
 687                         our_htlc_minimum_msat: Channel::derive_our_htlc_minimum_msat(msg.feerate_per_kw as u64),
 688                         their_to_self_delay: msg.to_self_delay,
 689                         their_max_accepted_htlcs: msg.max_accepted_htlcs,
 690                         minimum_depth: Channel::derive_minimum_depth(msg.funding_satoshis*1000, msg.push_msat),
 691
 692                         their_funding_pubkey: Some(msg.funding_pubkey),
 693                         their_revocation_basepoint: Some(msg.revocation_basepoint),
 694                         their_payment_basepoint: Some(msg.payment_basepoint),
 695                         their_delayed_payment_basepoint: Some(msg.delayed_payment_basepoint),
 696                         their_htlc_basepoint: Some(msg.htlc_basepoint),
 697                         their_cur_commitment_point: Some(msg.first_per_commitment_point),
 698
 699                         their_prev_commitment_point: None,
 700                         their_node_id: their_node_id,
 701
 702                         their_shutdown_scriptpubkey: None,
 703
 704                         channel_monitor: channel_monitor,
 705
 706                         logger,
 707                 };
 708
 709                 let obscure_factor = chan.get_commitment_transaction_number_obscure_factor();
 710                 chan.channel_monitor.set_commitment_obscure_factor(obscure_factor);
 711
 712                 Ok(chan)
 713         }
 714
 715         // Utilities to derive keys:
 716
 717         fn build_local_commitment_secret(&self, idx: u64) -> SecretKey {
 718                 let res = chan_utils::build_commitment_secret(self.local_keys.commitment_seed, idx);
 719                 SecretKey::from_slice(&res).unwrap()
 720         }
 721
 722         // Utilities to build transactions:
 723
 724         fn get_commitment_transaction_number_obscure_factor(&self) -> u64 {
 725                 let mut sha = Sha256::engine();
 726                 let our_payment_basepoint = PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.payment_base_key);
 727
 728                 if self.channel_outbound {
 729                         sha.input(&our_payment_basepoint.serialize());
 730                         sha.input(&self.their_payment_basepoint.unwrap().serialize());
 731                 } else {
 732                         sha.input(&self.their_payment_basepoint.unwrap().serialize());
 733                         sha.input(&our_payment_basepoint.serialize());
 734                 }
 735                 let res = Sha256::from_engine(sha).into_inner();
 736
 737                 ((res[26] as u64) << 5*8) |
 738                 ((res[27] as u64) << 4*8) |
 739                 ((res[28] as u64) << 3*8) |
 740                 ((res[29] as u64) << 2*8) |
 741                 ((res[30] as u64) << 1*8) |
 742                 ((res[31] as u64) << 0*8)
 743         }
 744
 745         /// Transaction nomenclature is somewhat confusing here as there are many different cases - a
 746         /// transaction is referred to as "a's transaction" implying that a will be able to broadcast
 747         /// the transaction. Thus, b will generally be sending a signature over such a transaction to
 748         /// a, and a can revoke the transaction by providing b the relevant per_commitment_secret. As
 749         /// such, a transaction is generally the result of b increasing the amount paid to a (or adding
 750         /// an HTLC to a).
 751         /// @local is used only to convert relevant internal structures which refer to remote vs local
 752         /// to decide value of outputs and direction of HTLCs.
 753         /// @generated_by_local is used to determine *which* HTLCs to include - noting that the HTLC
 754         /// state may indicate that one peer has informed the other that they'd like to add an HTLC but
 755         /// have not yet committed it. Such HTLCs will only be included in transactions which are being
 756         /// generated by the peer which proposed adding the HTLCs, and thus we need to understand both
 757         /// which peer generated this transaction and "to whom" this transaction flows.
 758         /// Returns (the transaction built, the number of HTLC outputs which were present in the
 759         /// transaction, the list of HTLCs which were not ignored when building the transaction).
 760         /// Note that below-dust HTLCs are included in the third return value, but not the second, and
 761         /// sources are provided only for outbound HTLCs in the third return value.
 762         #[inline]
 763         fn build_commitment_transaction(&self, commitment_number: u64, keys: &TxCreationKeys, local: bool, generated_by_local: bool, feerate_per_kw: u64) -> (Transaction, usize, Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)>) {
 764                 let obscured_commitment_transaction_number = self.get_commitment_transaction_number_obscure_factor() ^ (INITIAL_COMMITMENT_NUMBER - commitment_number);
 765
 766                 let txins = {
 767                         let mut ins: Vec<TxIn> = Vec::new();
 768                         ins.push(TxIn {
 769                                 previous_output: self.channel_monitor.get_funding_txo().unwrap().into_bitcoin_outpoint(),
 770                                 script_sig: Script::new(),
 771                                 sequence: ((0x80 as u32) << 8*3) | ((obscured_commitment_transaction_number >> 3*8) as u32),
 772                                 witness: Vec::new(),
 773                         });
 774                         ins
 775                 };
 776
 777                 let mut txouts: Vec<(TxOut, Option<(HTLCOutputInCommitment, Option<&HTLCSource>)>)> = Vec::with_capacity(self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len() + 2);
 778                 let mut included_dust_htlcs: Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)> = Vec::new();
 779
 780                 let dust_limit_satoshis = if local { self.our_dust_limit_satoshis } else { self.their_dust_limit_satoshis };
 781                 let mut remote_htlc_total_msat = 0;
 782                 let mut local_htlc_total_msat = 0;
 783                 let mut value_to_self_msat_offset = 0;
 784
 785                 log_trace!(self, "Building commitment transaction number {} for {}, generated by {} with fee {}...", commitment_number, if local { "us" } else { "remote" }, if generated_by_local { "us" } else { "remote" }, feerate_per_kw);
 786
 787                 macro_rules! get_htlc_in_commitment {
 788                         ($htlc: expr, $offered: expr) => {
 789                                 HTLCOutputInCommitment {
 790                                         offered: $offered,
 791                                         amount_msat: $htlc.amount_msat,
 792                                         cltv_expiry: $htlc.cltv_expiry,
 793                                         payment_hash: $htlc.payment_hash,
 794                                         transaction_output_index: None
 795                                 }
 796                         }
 797                 }
 798
 799                 macro_rules! add_htlc_output {
 800                         ($htlc: expr, $outbound: expr, $source: expr, $state_name: expr) => {
 801                                 if $outbound == local { // "offered HTLC output"
 802                                         let htlc_in_tx = get_htlc_in_commitment!($htlc, true);
 803                                         if $htlc.amount_msat / 1000 >= dust_limit_satoshis + (feerate_per_kw * HTLC_TIMEOUT_TX_WEIGHT / 1000) {
 804                                                 log_trace!(self, "   ...including {} {} HTLC {} (hash {}) with value {}", if $outbound { "outbound" } else { "inbound" }, $state_name, $htlc.htlc_id, log_bytes!($htlc.payment_hash.0), $htlc.amount_msat);
 805                                                 txouts.push((TxOut {
 806                                                         script_pubkey: chan_utils::get_htlc_redeemscript(&htlc_in_tx, &keys).to_v0_p2wsh(),
 807                                                         value: $htlc.amount_msat / 1000
 808                                                 }, Some((htlc_in_tx, $source))));
 809                                         } else {
 810                                                 log_trace!(self, "   ...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);
 811                                                 included_dust_htlcs.push((htlc_in_tx, $source));
 812                                         }
 813                                 } else {
 814                                         let htlc_in_tx = get_htlc_in_commitment!($htlc, false);
 815                                         if $htlc.amount_msat / 1000 >= dust_limit_satoshis + (feerate_per_kw * HTLC_SUCCESS_TX_WEIGHT / 1000) {
 816                                                 log_trace!(self, "   ...including {} {} HTLC {} (hash {}) with value {}", if $outbound { "outbound" } else { "inbound" }, $state_name, $htlc.htlc_id, log_bytes!($htlc.payment_hash.0), $htlc.amount_msat);
 817                                                 txouts.push((TxOut { // "received HTLC output"
 818                                                         script_pubkey: chan_utils::get_htlc_redeemscript(&htlc_in_tx, &keys).to_v0_p2wsh(),
 819                                                         value: $htlc.amount_msat / 1000
 820                                                 }, Some((htlc_in_tx, $source))));
 821                                         } else {
 822                                                 log_trace!(self, "   ...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);
 823                                                 included_dust_htlcs.push((htlc_in_tx, $source));
 824                                         }
 825                                 }
 826                         }
 827                 }
 828
 829                 for ref htlc in self.pending_inbound_htlcs.iter() {
 830                         let (include, state_name) = match htlc.state {
 831                                 InboundHTLCState::RemoteAnnounced(_) => (!generated_by_local, "RemoteAnnounced"),
 832                                 InboundHTLCState::AwaitingRemoteRevokeToAnnounce(_) => (!generated_by_local, "AwaitingRemoteRevokeToAnnounce"),
 833                                 InboundHTLCState::AwaitingAnnouncedRemoteRevoke(_) => (true, "AwaitingAnnouncedRemoteRevoke"),
 834                                 InboundHTLCState::Committed => (true, "Committed"),
 835                                 InboundHTLCState::LocalRemoved(_) => (!generated_by_local, "LocalRemoved"),
 836                         };
 837
 838                         if include {
 839                                 add_htlc_output!(htlc, false, None, state_name);
 840                                 remote_htlc_total_msat += htlc.amount_msat;
 841                         } else {
 842                                 log_trace!(self, "   ...not including inbound HTLC {} (hash {}) with value {} due to state ({})", htlc.htlc_id, log_bytes!(htlc.payment_hash.0), htlc.amount_msat, state_name);
 843                                 match &htlc.state {
 844                                         &InboundHTLCState::LocalRemoved(ref reason) => {
 845                                                 if generated_by_local {
 846                                                         if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
 847                                                                 value_to_self_msat_offset += htlc.amount_msat as i64;
 848                                                         }
 849                                                 }
 850                                         },
 851                                         _ => {},
 852                                 }
 853                         }
 854                 }
 855
 856                 for ref htlc in self.pending_outbound_htlcs.iter() {
 857                         let (include, state_name) = match htlc.state {
 858                                 OutboundHTLCState::LocalAnnounced(_) => (generated_by_local, "LocalAnnounced"),
 859                                 OutboundHTLCState::Committed => (true, "Committed"),
 860                                 OutboundHTLCState::RemoteRemoved(_) => (generated_by_local, "RemoteRemoved"),
 861                                 OutboundHTLCState::AwaitingRemoteRevokeToRemove(_) => (generated_by_local, "AwaitingRemoteRevokeToRemove"),
 862                                 OutboundHTLCState::AwaitingRemovedRemoteRevoke(_) => (false, "AwaitingRemovedRemoteRevoke"),
 863                         };
 864
 865                         if include {
 866                                 add_htlc_output!(htlc, true, Some(&htlc.source), state_name);
 867                                 local_htlc_total_msat += htlc.amount_msat;
 868                         } else {
 869                                 log_trace!(self, "   ...not including outbound HTLC {} (hash {}) with value {} due to state ({})", htlc.htlc_id, log_bytes!(htlc.payment_hash.0), htlc.amount_msat, state_name);
 870                                 match htlc.state {
 871                                         OutboundHTLCState::AwaitingRemoteRevokeToRemove(None)|OutboundHTLCState::AwaitingRemovedRemoteRevoke(None) => {
 872                                                 value_to_self_msat_offset -= htlc.amount_msat as i64;
 873                                         },
 874                                         OutboundHTLCState::RemoteRemoved(None) => {
 875                                                 if !generated_by_local {
 876                                                         value_to_self_msat_offset -= htlc.amount_msat as i64;
 877                                                 }
 878                                         },
 879                                         _ => {},
 880                                 }
 881                         }
 882                 }
 883
 884                 let value_to_self_msat: i64 = (self.value_to_self_msat - local_htlc_total_msat) as i64 + value_to_self_msat_offset;
 885                 assert!(value_to_self_msat >= 0);
 886                 // Note that in case they have several just-awaiting-last-RAA fulfills in-progress (ie
 887                 // AwaitingRemoteRevokeToRemove or AwaitingRemovedRemoteRevoke) we may have allowed them to
 888                 // "violate" their reserve value by couting those against it. Thus, we have to convert
 889                 // everything to i64 before subtracting as otherwise we can overflow.
 890                 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;
 891                 assert!(value_to_remote_msat >= 0);
 892
 893                 #[cfg(debug_assertions)]
 894                 {
 895                         // Make sure that the to_self/to_remote is always either past the appropriate
 896                         // channel_reserve *or* it is making progress towards it.
 897                         // TODO: This should happen after fee calculation, but we don't handle that correctly
 898                         // yet!
 899                         let mut max_commitment_tx_output = if generated_by_local {
 900                                 self.max_commitment_tx_output_local.lock().unwrap()
 901                         } else {
 902                                 self.max_commitment_tx_output_remote.lock().unwrap()
 903                         };
 904                         debug_assert!(max_commitment_tx_output.0 <= value_to_self_msat as u64 || value_to_self_msat / 1000 >= self.their_channel_reserve_satoshis as i64);
 905                         max_commitment_tx_output.0 = cmp::max(max_commitment_tx_output.0, value_to_self_msat as u64);
 906                         debug_assert!(max_commitment_tx_output.1 <= value_to_remote_msat as u64 || value_to_remote_msat / 1000 >= Channel::get_our_channel_reserve_satoshis(self.channel_value_satoshis) as i64);
 907                         max_commitment_tx_output.1 = cmp::max(max_commitment_tx_output.1, value_to_remote_msat as u64);
 908                 }
 909
 910                 let total_fee: u64 = feerate_per_kw * (COMMITMENT_TX_BASE_WEIGHT + (txouts.len() as u64) * COMMITMENT_TX_WEIGHT_PER_HTLC) / 1000;
 911                 let (value_to_self, value_to_remote) = if self.channel_outbound {
 912                         (value_to_self_msat / 1000 - total_fee as i64, value_to_remote_msat / 1000)
 913                 } else {
 914                         (value_to_self_msat / 1000, value_to_remote_msat / 1000 - total_fee as i64)
 915                 };
 916
 917                 let value_to_a = if local { value_to_self } else { value_to_remote };
 918                 let value_to_b = if local { value_to_remote } else { value_to_self };
 919
 920                 if value_to_a >= (dust_limit_satoshis as i64) {
 921                         txouts.push((TxOut {
 922                                 script_pubkey: chan_utils::get_revokeable_redeemscript(&keys.revocation_key,
 923                                                                                        if local { self.their_to_self_delay } else { BREAKDOWN_TIMEOUT },
 924                                                                                        &keys.a_delayed_payment_key).to_v0_p2wsh(),
 925                                 value: value_to_a as u64
 926                         }, None));
 927                 }
 928
 929                 if value_to_b >= (dust_limit_satoshis as i64) {
 930                         txouts.push((TxOut {
 931                                 script_pubkey: Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0)
 932                                                              .push_slice(&Hash160::hash(&keys.b_payment_key.serialize())[..])
 933                                                              .into_script(),
 934                                 value: value_to_b as u64
 935                         }, None));
 936                 }
 937
 938                 transaction_utils::sort_outputs(&mut txouts);
 939
 940                 let mut outputs: Vec<TxOut> = Vec::with_capacity(txouts.len());
 941                 let mut htlcs_included: Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)> = Vec::with_capacity(txouts.len() + included_dust_htlcs.len());
 942                 for (idx, mut out) in txouts.drain(..).enumerate() {
 943                         outputs.push(out.0);
 944                         if let Some((mut htlc, source_option)) = out.1.take() {
 945                                 htlc.transaction_output_index = Some(idx as u32);
 946                                 htlcs_included.push((htlc, source_option));
 947                         }
 948                 }
 949                 let non_dust_htlc_count = htlcs_included.len();
 950                 htlcs_included.append(&mut included_dust_htlcs);
 951
 952                 (Transaction {
 953                         version: 2,
 954                         lock_time: ((0x20 as u32) << 8*3) | ((obscured_commitment_transaction_number & 0xffffffu64) as u32),
 955                         input: txins,
 956                         output: outputs,
 957                 }, non_dust_htlc_count, htlcs_included)
 958         }
 959
 960         #[inline]
 961         fn get_closing_scriptpubkey(&self) -> Script {
 962                 let our_channel_close_key_hash = Hash160::hash(&self.shutdown_pubkey.serialize());
 963                 Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&our_channel_close_key_hash[..]).into_script()
 964         }
 965
 966         #[inline]
 967         fn get_closing_transaction_weight(a_scriptpubkey: &Script, b_scriptpubkey: &Script) -> u64 {
 968                 (4 + 1 + 36 + 4 + 1 + 1 + 2*(8+1) + 4 + a_scriptpubkey.len() as u64 + b_scriptpubkey.len() as u64)*4 + 2 + 1 + 1 + 2*(1 + 72)
 969         }
 970
 971         #[inline]
 972         fn build_closing_transaction(&self, proposed_total_fee_satoshis: u64, skip_remote_output: bool) -> (Transaction, u64) {
 973                 let txins = {
 974                         let mut ins: Vec<TxIn> = Vec::new();
 975                         ins.push(TxIn {
 976                                 previous_output: self.channel_monitor.get_funding_txo().unwrap().into_bitcoin_outpoint(),
 977                                 script_sig: Script::new(),
 978                                 sequence: 0xffffffff,
 979                                 witness: Vec::new(),
 980                         });
 981                         ins
 982                 };
 983
 984                 assert!(self.pending_inbound_htlcs.is_empty());
 985                 assert!(self.pending_outbound_htlcs.is_empty());
 986                 let mut txouts: Vec<(TxOut, ())> = Vec::new();
 987
 988                 let mut total_fee_satoshis = proposed_total_fee_satoshis;
 989                 let value_to_self: i64 = (self.value_to_self_msat as i64) / 1000 - if self.channel_outbound { total_fee_satoshis as i64 } else { 0 };
 990                 let value_to_remote: i64 = ((self.channel_value_satoshis * 1000 - self.value_to_self_msat) as i64 / 1000) - if self.channel_outbound { 0 } else { total_fee_satoshis as i64 };
 991
 992                 if value_to_self < 0 {
 993                         assert!(self.channel_outbound);
 994                         total_fee_satoshis += (-value_to_self) as u64;
 995                 } else if value_to_remote < 0 {
 996                         assert!(!self.channel_outbound);
 997                         total_fee_satoshis += (-value_to_remote) as u64;
 998                 }
 999
1000                 if !skip_remote_output && value_to_remote as u64 > self.our_dust_limit_satoshis {
1001                         txouts.push((TxOut {
1002                                 script_pubkey: self.their_shutdown_scriptpubkey.clone().unwrap(),
1003                                 value: value_to_remote as u64
1004                         }, ()));
1005                 }
1006
1007                 if value_to_self as u64 > self.our_dust_limit_satoshis {
1008                         txouts.push((TxOut {
1009                                 script_pubkey: self.get_closing_scriptpubkey(),
1010                                 value: value_to_self as u64
1011                         }, ()));
1012                 }
1013
1014                 transaction_utils::sort_outputs(&mut txouts);
1015
1016                 let mut outputs: Vec<TxOut> = Vec::new();
1017                 for out in txouts.drain(..) {
1018                         outputs.push(out.0);
1019                 }
1020
1021                 (Transaction {
1022                         version: 2,
1023                         lock_time: 0,
1024                         input: txins,
1025                         output: outputs,
1026                 }, total_fee_satoshis)
1027         }
1028
1029         #[inline]
1030         /// Creates a set of keys for build_commitment_transaction to generate a transaction which our
1031         /// counterparty will sign (ie DO NOT send signatures over a transaction created by this to
1032         /// our counterparty!)
1033         /// The result is a transaction which we can revoke ownership of (ie a "local" transaction)
1034         /// TODO Some magic rust shit to compile-time check this?
1035         fn build_local_transaction_keys(&self, commitment_number: u64) -> Result<TxCreationKeys, ChannelError> {
1036                 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &self.build_local_commitment_secret(commitment_number));
1037                 let delayed_payment_base = PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.delayed_payment_base_key);
1038                 let htlc_basepoint = PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.htlc_base_key);
1039
1040                 Ok(secp_check!(TxCreationKeys::new(&self.secp_ctx, &per_commitment_point, &delayed_payment_base, &htlc_basepoint, &self.their_revocation_basepoint.unwrap(), &self.their_payment_basepoint.unwrap(), &self.their_htlc_basepoint.unwrap()), "Local tx keys generation got bogus keys"))
1041         }
1042
1043         #[inline]
1044         /// Creates a set of keys for build_commitment_transaction to generate a transaction which we
1045         /// will sign and send to our counterparty.
1046         /// If an Err is returned, it is a ChannelError::Close (for get_outbound_funding_created)
1047         fn build_remote_transaction_keys(&self) -> Result<TxCreationKeys, ChannelError> {
1048                 //TODO: Ensure that the payment_key derived here ends up in the library users' wallet as we
1049                 //may see payments to it!
1050                 let payment_basepoint = PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.payment_base_key);
1051                 let revocation_basepoint = PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.revocation_base_key);
1052                 let htlc_basepoint = PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.htlc_base_key);
1053
1054                 Ok(secp_check!(TxCreationKeys::new(&self.secp_ctx, &self.their_cur_commitment_point.unwrap(), &self.their_delayed_payment_basepoint.unwrap(), &self.their_htlc_basepoint.unwrap(), &revocation_basepoint, &payment_basepoint, &htlc_basepoint), "Remote tx keys generation got bogus keys"))
1055         }
1056
1057         /// Gets the redeemscript for the funding transaction output (ie the funding transaction output
1058         /// pays to get_funding_redeemscript().to_v0_p2wsh()).
1059         /// Panics if called before accept_channel/new_from_req
1060         pub fn get_funding_redeemscript(&self) -> Script {
1061                 let builder = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2);
1062                 let our_funding_key = PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.funding_key).serialize();
1063                 let their_funding_key = self.their_funding_pubkey.expect("get_funding_redeemscript only allowed after accept_channel").serialize();
1064                 if our_funding_key[..] < their_funding_key[..] {
1065                         builder.push_slice(&our_funding_key)
1066                                 .push_slice(&their_funding_key)
1067                 } else {
1068                         builder.push_slice(&their_funding_key)
1069                                 .push_slice(&our_funding_key)
1070                 }.push_opcode(opcodes::all::OP_PUSHNUM_2).push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script()
1071         }
1072
1073         fn sign_commitment_transaction(&self, tx: &mut Transaction, their_sig: &Signature) -> Signature {
1074                 if tx.input.len() != 1 {
1075                         panic!("Tried to sign commitment transaction that had input count != 1!");
1076                 }
1077                 if tx.input[0].witness.len() != 0 {
1078                         panic!("Tried to re-sign commitment transaction");
1079                 }
1080
1081                 let funding_redeemscript = self.get_funding_redeemscript();
1082
1083                 let sighash = hash_to_message!(&bip143::SighashComponents::new(&tx).sighash_all(&tx.input[0], &funding_redeemscript, self.channel_value_satoshis)[..]);
1084                 let our_sig = self.secp_ctx.sign(&sighash, &self.local_keys.funding_key);
1085
1086                 tx.input[0].witness.push(Vec::new()); // First is the multisig dummy
1087
1088                 let our_funding_key = PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.funding_key).serialize();
1089                 let their_funding_key = self.their_funding_pubkey.unwrap().serialize();
1090                 if our_funding_key[..] < their_funding_key[..] {
1091                         tx.input[0].witness.push(our_sig.serialize_der().to_vec());
1092                         tx.input[0].witness.push(their_sig.serialize_der().to_vec());
1093                 } else {
1094                         tx.input[0].witness.push(their_sig.serialize_der().to_vec());
1095                         tx.input[0].witness.push(our_sig.serialize_der().to_vec());
1096                 }
1097                 tx.input[0].witness[1].push(SigHashType::All as u8);
1098                 tx.input[0].witness[2].push(SigHashType::All as u8);
1099
1100                 tx.input[0].witness.push(funding_redeemscript.into_bytes());
1101
1102                 our_sig
1103         }
1104
1105         /// Builds the htlc-success or htlc-timeout transaction which spends a given HTLC output
1106         /// @local is used only to convert relevant internal structures which refer to remote vs local
1107         /// to decide value of outputs and direction of HTLCs.
1108         fn build_htlc_transaction(&self, prev_hash: &Sha256dHash, htlc: &HTLCOutputInCommitment, local: bool, keys: &TxCreationKeys, feerate_per_kw: u64) -> Transaction {
1109                 chan_utils::build_htlc_transaction(prev_hash, feerate_per_kw, if local { self.their_to_self_delay } else { BREAKDOWN_TIMEOUT }, htlc, &keys.a_delayed_payment_key, &keys.revocation_key)
1110         }
1111
1112         fn create_htlc_tx_signature(&self, tx: &Transaction, htlc: &HTLCOutputInCommitment, keys: &TxCreationKeys) -> Result<(Script, Signature, bool), ChannelError> {
1113                 if tx.input.len() != 1 {
1114                         panic!("Tried to sign HTLC transaction that had input count != 1!");
1115                 }
1116
1117                 let htlc_redeemscript = chan_utils::get_htlc_redeemscript(&htlc, &keys);
1118
1119                 let our_htlc_key = secp_check!(chan_utils::derive_private_key(&self.secp_ctx, &keys.per_commitment_point, &self.local_keys.htlc_base_key), "Derived invalid key, peer is maliciously selecting parameters");
1120                 let sighash = hash_to_message!(&bip143::SighashComponents::new(&tx).sighash_all(&tx.input[0], &htlc_redeemscript, htlc.amount_msat / 1000)[..]);
1121                 let is_local_tx = PublicKey::from_secret_key(&self.secp_ctx, &our_htlc_key) == keys.a_htlc_key;
1122                 Ok((htlc_redeemscript, self.secp_ctx.sign(&sighash, &our_htlc_key), is_local_tx))
1123         }
1124
1125         /// Signs a transaction created by build_htlc_transaction. If the transaction is an
1126         /// HTLC-Success transaction (ie htlc.offered is false), preimage must be set!
1127         fn sign_htlc_transaction(&self, tx: &mut Transaction, their_sig: &Signature, preimage: &Option<PaymentPreimage>, htlc: &HTLCOutputInCommitment, keys: &TxCreationKeys) -> Result<Signature, ChannelError> {
1128                 if tx.input.len() != 1 {
1129                         panic!("Tried to sign HTLC transaction that had input count != 1!");
1130                 }
1131                 if tx.input[0].witness.len() != 0 {
1132                         panic!("Tried to re-sign HTLC transaction");
1133                 }
1134
1135                 let (htlc_redeemscript, our_sig, local_tx) = self.create_htlc_tx_signature(tx, htlc, keys)?;
1136
1137                 tx.input[0].witness.push(Vec::new()); // First is the multisig dummy
1138
1139                 if local_tx { // b, then a
1140                         tx.input[0].witness.push(their_sig.serialize_der().to_vec());
1141                         tx.input[0].witness.push(our_sig.serialize_der().to_vec());
1142                 } else {
1143                         tx.input[0].witness.push(our_sig.serialize_der().to_vec());
1144                         tx.input[0].witness.push(their_sig.serialize_der().to_vec());
1145                 }
1146                 tx.input[0].witness[1].push(SigHashType::All as u8);
1147                 tx.input[0].witness[2].push(SigHashType::All as u8);
1148
1149                 if htlc.offered {
1150                         tx.input[0].witness.push(Vec::new());
1151                 } else {
1152                         tx.input[0].witness.push(preimage.unwrap().0.to_vec());
1153                 }
1154
1155                 tx.input[0].witness.push(htlc_redeemscript.into_bytes());
1156
1157                 Ok(our_sig)
1158         }
1159
1160         /// Per HTLC, only one get_update_fail_htlc or get_update_fulfill_htlc call may be made.
1161         /// In such cases we debug_assert!(false) and return an IgnoreError. Thus, will always return
1162         /// Ok(_) if debug assertions are turned on and preconditions are met.
1163         fn get_update_fulfill_htlc(&mut self, htlc_id_arg: u64, payment_preimage_arg: PaymentPreimage) -> Result<(Option<msgs::UpdateFulfillHTLC>, Option<ChannelMonitor>), ChannelError> {
1164                 // Either ChannelFunded got set (which means it won't be unset) or there is no way any
1165                 // caller thought we could have something claimed (cause we wouldn't have accepted in an
1166                 // incoming HTLC anyway). If we got to ShutdownComplete, callers aren't allowed to call us,
1167                 // either.
1168                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
1169                         panic!("Was asked to fulfill an HTLC when channel was not in an operational state");
1170                 }
1171                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
1172
1173                 let payment_hash_calc = PaymentHash(Sha256::hash(&payment_preimage_arg.0[..]).into_inner());
1174
1175                 // ChannelManager may generate duplicate claims/fails due to HTLC update events from
1176                 // on-chain ChannelsMonitors during block rescan. Ideally we'd figure out a way to drop
1177                 // these, but for now we just have to treat them as normal.
1178
1179                 let mut pending_idx = std::usize::MAX;
1180                 for (idx, htlc) in self.pending_inbound_htlcs.iter().enumerate() {
1181                         if htlc.htlc_id == htlc_id_arg {
1182                                 assert_eq!(htlc.payment_hash, payment_hash_calc);
1183                                 match htlc.state {
1184                                         InboundHTLCState::Committed => {},
1185                                         InboundHTLCState::LocalRemoved(ref reason) => {
1186                                                 if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
1187                                                 } else {
1188                                                         log_warn!(self, "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()));
1189                                                 }
1190                                                 return Ok((None, None));
1191                                         },
1192                                         _ => {
1193                                                 debug_assert!(false, "Have an inbound HTLC we tried to claim before it was fully committed to");
1194                                                 // Don't return in release mode here so that we can update channel_monitor
1195                                         }
1196                                 }
1197                                 pending_idx = idx;
1198                                 break;
1199                         }
1200                 }
1201                 if pending_idx == std::usize::MAX {
1202                         return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID"));
1203                 }
1204
1205                 // Now update local state:
1206                 //
1207                 // We have to put the payment_preimage in the channel_monitor right away here to ensure we
1208                 // can claim it even if the channel hits the chain before we see their next commitment.
1209                 self.channel_monitor.provide_payment_preimage(&payment_hash_calc, &payment_preimage_arg);
1210
1211                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32)) != 0 {
1212                         for pending_update in self.holding_cell_htlc_updates.iter() {
1213                                 match pending_update {
1214                                         &HTLCUpdateAwaitingACK::ClaimHTLC { htlc_id, .. } => {
1215                                                 if htlc_id_arg == htlc_id {
1216                                                         return Ok((None, None));
1217                                                 }
1218                                         },
1219                                         &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, .. } => {
1220                                                 if htlc_id_arg == htlc_id {
1221                                                         log_warn!(self, "Have preimage and want to fulfill HTLC with pending failure against channel {}", log_bytes!(self.channel_id()));
1222                                                         // TODO: We may actually be able to switch to a fulfill here, though its
1223                                                         // rare enough it may not be worth the complexity burden.
1224                                                         return Ok((None, Some(self.channel_monitor.clone())));
1225                                                 }
1226                                         },
1227                                         _ => {}
1228                                 }
1229                         }
1230                         log_trace!(self, "Adding HTLC claim to holding_cell! Current state: {}", self.channel_state);
1231                         self.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::ClaimHTLC {
1232                                 payment_preimage: payment_preimage_arg, htlc_id: htlc_id_arg,
1233                         });
1234                         return Ok((None, Some(self.channel_monitor.clone())));
1235                 }
1236
1237                 {
1238                         let htlc = &mut self.pending_inbound_htlcs[pending_idx];
1239                         if let InboundHTLCState::Committed = htlc.state {
1240                         } else {
1241                                 debug_assert!(false, "Have an inbound HTLC we tried to claim before it was fully committed to");
1242                                 return Ok((None, Some(self.channel_monitor.clone())));
1243                         }
1244                         log_trace!(self, "Upgrading HTLC {} to LocalRemoved with a Fulfill!", log_bytes!(htlc.payment_hash.0));
1245                         htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::Fulfill(payment_preimage_arg.clone()));
1246                 }
1247
1248                 Ok((Some(msgs::UpdateFulfillHTLC {
1249                         channel_id: self.channel_id(),
1250                         htlc_id: htlc_id_arg,
1251                         payment_preimage: payment_preimage_arg,
1252                 }), Some(self.channel_monitor.clone())))
1253         }
1254
1255         pub fn get_update_fulfill_htlc_and_commit(&mut self, htlc_id: u64, payment_preimage: PaymentPreimage) -> Result<(Option<(msgs::UpdateFulfillHTLC, msgs::CommitmentSigned)>, Option<ChannelMonitor>), ChannelError> {
1256                 match self.get_update_fulfill_htlc(htlc_id, payment_preimage)? {
1257                         (Some(update_fulfill_htlc), _) => {
1258                                 let (commitment, monitor_update) = self.send_commitment_no_status_check()?;
1259                                 Ok((Some((update_fulfill_htlc, commitment)), Some(monitor_update)))
1260                         },
1261                         (None, Some(channel_monitor)) => Ok((None, Some(channel_monitor))),
1262                         (None, None) => Ok((None, None))
1263                 }
1264         }
1265
1266         /// Per HTLC, only one get_update_fail_htlc or get_update_fulfill_htlc call may be made.
1267         /// In such cases we debug_assert!(false) and return an IgnoreError. Thus, will always return
1268         /// Ok(_) if debug assertions are turned on and preconditions are met.
1269         pub fn get_update_fail_htlc(&mut self, htlc_id_arg: u64, err_packet: msgs::OnionErrorPacket) -> Result<Option<msgs::UpdateFailHTLC>, ChannelError> {
1270                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
1271                         panic!("Was asked to fail an HTLC when channel was not in an operational state");
1272                 }
1273                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
1274
1275                 // ChannelManager may generate duplicate claims/fails due to HTLC update events from
1276                 // on-chain ChannelsMonitors during block rescan. Ideally we'd figure out a way to drop
1277                 // these, but for now we just have to treat them as normal.
1278
1279                 let mut pending_idx = std::usize::MAX;
1280                 for (idx, htlc) in self.pending_inbound_htlcs.iter().enumerate() {
1281                         if htlc.htlc_id == htlc_id_arg {
1282                                 match htlc.state {
1283                                         InboundHTLCState::Committed => {},
1284                                         InboundHTLCState::LocalRemoved(_) => {
1285                                                 return Ok(None);
1286                                         },
1287                                         _ => {
1288                                                 debug_assert!(false, "Have an inbound HTLC we tried to claim before it was fully committed to");
1289                                                 return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID"));
1290                                         }
1291                                 }
1292                                 pending_idx = idx;
1293                         }
1294                 }
1295                 if pending_idx == std::usize::MAX {
1296                         return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID"));
1297                 }
1298
1299                 // Now update local state:
1300                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32)) != 0 {
1301                         for pending_update in self.holding_cell_htlc_updates.iter() {
1302                                 match pending_update {
1303                                         &HTLCUpdateAwaitingACK::ClaimHTLC { htlc_id, .. } => {
1304                                                 if htlc_id_arg == htlc_id {
1305                                                         return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID"));
1306                                                 }
1307                                         },
1308                                         &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, .. } => {
1309                                                 if htlc_id_arg == htlc_id {
1310                                                         return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID"));
1311                                                 }
1312                                         },
1313                                         _ => {}
1314                                 }
1315                         }
1316                         self.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::FailHTLC {
1317                                 htlc_id: htlc_id_arg,
1318                                 err_packet,
1319                         });
1320                         return Ok(None);
1321                 }
1322
1323                 {
1324                         let htlc = &mut self.pending_inbound_htlcs[pending_idx];
1325                         htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::FailRelay(err_packet.clone()));
1326                 }
1327
1328                 Ok(Some(msgs::UpdateFailHTLC {
1329                         channel_id: self.channel_id(),
1330                         htlc_id: htlc_id_arg,
1331                         reason: err_packet
1332                 }))
1333         }
1334
1335         // Message handlers:
1336
1337         pub fn accept_channel(&mut self, msg: &msgs::AcceptChannel, config: &UserConfig) -> Result<(), ChannelError> {
1338                 // Check sanity of message fields:
1339                 if !self.channel_outbound {
1340                         return Err(ChannelError::Close("Got an accept_channel message from an inbound peer"));
1341                 }
1342                 if self.channel_state != ChannelState::OurInitSent as u32 {
1343                         return Err(ChannelError::Close("Got an accept_channel message at a strange time"));
1344                 }
1345                 if msg.dust_limit_satoshis > 21000000 * 100000000 {
1346                         return Err(ChannelError::Close("Peer never wants payout outputs?"));
1347                 }
1348                 if msg.channel_reserve_satoshis > self.channel_value_satoshis {
1349                         return Err(ChannelError::Close("Bogus channel_reserve_satoshis"));
1350                 }
1351                 if msg.dust_limit_satoshis > msg.channel_reserve_satoshis {
1352                         return Err(ChannelError::Close("Bogus channel_reserve and dust_limit"));
1353                 }
1354                 if msg.channel_reserve_satoshis < self.our_dust_limit_satoshis {
1355                         return Err(ChannelError::Close("Peer never wants payout outputs?"));
1356                 }
1357                 if msg.dust_limit_satoshis > Channel::get_our_channel_reserve_satoshis(self.channel_value_satoshis) {
1358                         return Err(ChannelError::Close("Dust limit is bigger than our channel reverse"));
1359                 }
1360                 if msg.htlc_minimum_msat >= (self.channel_value_satoshis - msg.channel_reserve_satoshis) * 1000 {
1361                         return Err(ChannelError::Close("Minimum htlc value is full channel value"));
1362                 }
1363                 if msg.to_self_delay > MAX_LOCAL_BREAKDOWN_TIMEOUT {
1364                         return Err(ChannelError::Close("They wanted our payments to be delayed by a needlessly long period"));
1365                 }
1366                 if msg.max_accepted_htlcs < 1 {
1367                         return Err(ChannelError::Close("0 max_accepted_htlcs makes for a useless channel"));
1368                 }
1369                 if msg.max_accepted_htlcs > 483 {
1370                         return Err(ChannelError::Close("max_accepted_htlcs > 483"));
1371                 }
1372
1373                 // Now check against optional parameters as set by config...
1374                 if msg.htlc_minimum_msat > config.channel_limits.max_htlc_minimum_msat {
1375                         return Err(ChannelError::Close("htlc minimum msat is higher than the user specified limit"));
1376                 }
1377                 if msg.max_htlc_value_in_flight_msat < config.channel_limits.min_max_htlc_value_in_flight_msat {
1378                         return Err(ChannelError::Close("max htlc value in flight msat is less than the user specified limit"));
1379                 }
1380                 if msg.channel_reserve_satoshis > config.channel_limits.max_channel_reserve_satoshis {
1381                         return Err(ChannelError::Close("channel reserve satoshis is higher than the user specified limit"));
1382                 }
1383                 if msg.max_accepted_htlcs < config.channel_limits.min_max_accepted_htlcs {
1384                         return Err(ChannelError::Close("max accepted htlcs is less than the user specified limit"));
1385                 }
1386                 if msg.dust_limit_satoshis < config.channel_limits.min_dust_limit_satoshis {
1387                         return Err(ChannelError::Close("dust limit satoshis is less than the user specified limit"));
1388                 }
1389                 if msg.dust_limit_satoshis > config.channel_limits.max_dust_limit_satoshis {
1390                         return Err(ChannelError::Close("dust limit satoshis is greater than the user specified limit"));
1391                 }
1392                 if msg.minimum_depth > config.channel_limits.max_minimum_depth {
1393                         return Err(ChannelError::Close("We consider the minimum depth to be unreasonably large"));
1394                 }
1395
1396                 self.channel_monitor.set_their_base_keys(&msg.htlc_basepoint, &msg.delayed_payment_basepoint);
1397
1398                 self.their_dust_limit_satoshis = msg.dust_limit_satoshis;
1399                 self.their_max_htlc_value_in_flight_msat = cmp::min(msg.max_htlc_value_in_flight_msat, self.channel_value_satoshis * 1000);
1400                 self.their_channel_reserve_satoshis = msg.channel_reserve_satoshis;
1401                 self.their_htlc_minimum_msat = msg.htlc_minimum_msat;
1402                 self.their_to_self_delay = msg.to_self_delay;
1403                 self.their_max_accepted_htlcs = msg.max_accepted_htlcs;
1404                 self.minimum_depth = msg.minimum_depth;
1405                 self.their_funding_pubkey = Some(msg.funding_pubkey);
1406                 self.their_revocation_basepoint = Some(msg.revocation_basepoint);
1407                 self.their_payment_basepoint = Some(msg.payment_basepoint);
1408                 self.their_delayed_payment_basepoint = Some(msg.delayed_payment_basepoint);
1409                 self.their_htlc_basepoint = Some(msg.htlc_basepoint);
1410                 self.their_cur_commitment_point = Some(msg.first_per_commitment_point);
1411
1412                 let obscure_factor = self.get_commitment_transaction_number_obscure_factor();
1413                 self.channel_monitor.set_commitment_obscure_factor(obscure_factor);
1414                 self.channel_monitor.set_their_to_self_delay(msg.to_self_delay);
1415
1416                 self.channel_state = ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32;
1417
1418                 Ok(())
1419         }
1420
1421         fn funding_created_signature(&mut self, sig: &Signature) -> Result<(Transaction, Transaction, Signature, TxCreationKeys), ChannelError> {
1422                 let funding_script = self.get_funding_redeemscript();
1423
1424                 let local_keys = self.build_local_transaction_keys(self.cur_local_commitment_transaction_number)?;
1425                 let mut local_initial_commitment_tx = self.build_commitment_transaction(self.cur_local_commitment_transaction_number, &local_keys, true, false, self.feerate_per_kw).0;
1426                 let local_sighash = hash_to_message!(&bip143::SighashComponents::new(&local_initial_commitment_tx).sighash_all(&local_initial_commitment_tx.input[0], &funding_script, self.channel_value_satoshis)[..]);
1427
1428                 // They sign the "local" commitment transaction...
1429                 secp_check!(self.secp_ctx.verify(&local_sighash, &sig, &self.their_funding_pubkey.unwrap()), "Invalid funding_created signature from peer");
1430
1431                 // ...and we sign it, allowing us to broadcast the tx if we wish
1432                 self.sign_commitment_transaction(&mut local_initial_commitment_tx, sig);
1433
1434                 let remote_keys = self.build_remote_transaction_keys()?;
1435                 let remote_initial_commitment_tx = self.build_commitment_transaction(self.cur_remote_commitment_transaction_number, &remote_keys, false, false, self.feerate_per_kw).0;
1436                 let remote_sighash = hash_to_message!(&bip143::SighashComponents::new(&remote_initial_commitment_tx).sighash_all(&remote_initial_commitment_tx.input[0], &funding_script, self.channel_value_satoshis)[..]);
1437
1438                 // We sign the "remote" commitment transaction, allowing them to broadcast the tx if they wish.
1439                 Ok((remote_initial_commitment_tx, local_initial_commitment_tx, self.secp_ctx.sign(&remote_sighash, &self.local_keys.funding_key), local_keys))
1440         }
1441
1442         pub fn funding_created(&mut self, msg: &msgs::FundingCreated) -> Result<(msgs::FundingSigned, ChannelMonitor), ChannelError> {
1443                 if self.channel_outbound {
1444                         return Err(ChannelError::Close("Received funding_created for an outbound channel?"));
1445                 }
1446                 if self.channel_state != (ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32) {
1447                         // BOLT 2 says that if we disconnect before we send funding_signed we SHOULD NOT
1448                         // remember the channel, so it's safe to just send an error_message here and drop the
1449                         // channel.
1450                         return Err(ChannelError::Close("Received funding_created after we got the channel!"));
1451                 }
1452                 if self.channel_monitor.get_min_seen_secret() != (1 << 48) ||
1453                                 self.cur_remote_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER ||
1454                                 self.cur_local_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
1455                         panic!("Should not have advanced channel commitment tx numbers prior to funding_created");
1456                 }
1457
1458                 let funding_txo = OutPoint::new(msg.funding_txid, msg.funding_output_index);
1459                 let funding_txo_script = self.get_funding_redeemscript().to_v0_p2wsh();
1460                 self.channel_monitor.set_funding_info((funding_txo, funding_txo_script));
1461
1462                 let (remote_initial_commitment_tx, local_initial_commitment_tx, our_signature, local_keys) = match self.funding_created_signature(&msg.signature) {
1463                         Ok(res) => res,
1464                         Err(e) => {
1465                                 self.channel_monitor.unset_funding_info();
1466                                 return Err(e);
1467                         }
1468                 };
1469
1470                 // Now that we're past error-generating stuff, update our local state:
1471
1472                 self.channel_monitor.provide_latest_remote_commitment_tx_info(&remote_initial_commitment_tx, Vec::new(), self.cur_remote_commitment_transaction_number, self.their_cur_commitment_point.unwrap());
1473                 self.last_local_commitment_txn = vec![local_initial_commitment_tx.clone()];
1474                 self.channel_monitor.provide_latest_local_commitment_tx_info(local_initial_commitment_tx, local_keys, self.feerate_per_kw, Vec::new());
1475                 self.channel_state = ChannelState::FundingSent as u32;
1476                 self.channel_id = funding_txo.to_channel_id();
1477                 self.cur_remote_commitment_transaction_number -= 1;
1478                 self.cur_local_commitment_transaction_number -= 1;
1479
1480                 Ok((msgs::FundingSigned {
1481                         channel_id: self.channel_id,
1482                         signature: our_signature
1483                 }, self.channel_monitor.clone()))
1484         }
1485
1486         /// Handles a funding_signed message from the remote end.
1487         /// If this call is successful, broadcast the funding transaction (and not before!)
1488         pub fn funding_signed(&mut self, msg: &msgs::FundingSigned) -> Result<ChannelMonitor, ChannelError> {
1489                 if !self.channel_outbound {
1490                         return Err(ChannelError::Close("Received funding_signed for an inbound channel?"));
1491                 }
1492                 if self.channel_state != ChannelState::FundingCreated as u32 {
1493                         return Err(ChannelError::Close("Received funding_signed in strange state!"));
1494                 }
1495                 if self.channel_monitor.get_min_seen_secret() != (1 << 48) ||
1496                                 self.cur_remote_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER - 1 ||
1497                                 self.cur_local_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
1498                         panic!("Should not have advanced channel commitment tx numbers prior to funding_created");
1499                 }
1500
1501                 let funding_script = self.get_funding_redeemscript();
1502
1503                 let local_keys = self.build_local_transaction_keys(self.cur_local_commitment_transaction_number)?;
1504                 let mut local_initial_commitment_tx = self.build_commitment_transaction(self.cur_local_commitment_transaction_number, &local_keys, true, false, self.feerate_per_kw).0;
1505                 let local_sighash = hash_to_message!(&bip143::SighashComponents::new(&local_initial_commitment_tx).sighash_all(&local_initial_commitment_tx.input[0], &funding_script, self.channel_value_satoshis)[..]);
1506
1507                 // They sign the "local" commitment transaction, allowing us to broadcast the tx if we wish.
1508                 secp_check!(self.secp_ctx.verify(&local_sighash, &msg.signature, &self.their_funding_pubkey.unwrap()), "Invalid funding_signed signature from peer");
1509
1510                 self.sign_commitment_transaction(&mut local_initial_commitment_tx, &msg.signature);
1511                 self.channel_monitor.provide_latest_local_commitment_tx_info(local_initial_commitment_tx.clone(), local_keys, self.feerate_per_kw, Vec::new());
1512                 self.last_local_commitment_txn = vec![local_initial_commitment_tx];
1513                 self.channel_state = ChannelState::FundingSent as u32;
1514                 self.cur_local_commitment_transaction_number -= 1;
1515
1516                 Ok(self.channel_monitor.clone())
1517         }
1518
1519         pub fn funding_locked(&mut self, msg: &msgs::FundingLocked) -> Result<(), ChannelError> {
1520                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
1521                         return Err(ChannelError::Close("Peer sent funding_locked when we needed a channel_reestablish"));
1522                 }
1523
1524                 let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
1525
1526                 if non_shutdown_state == ChannelState::FundingSent as u32 {
1527                         self.channel_state |= ChannelState::TheirFundingLocked as u32;
1528                 } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::OurFundingLocked as u32) {
1529                         self.channel_state = ChannelState::ChannelFunded as u32 | (self.channel_state & MULTI_STATE_FLAGS);
1530                         self.channel_update_count += 1;
1531                 } else if self.channel_state & (ChannelState::ChannelFunded as u32) != 0 &&
1532                                 // Note that funding_signed/funding_created will have decremented both by 1!
1533                                 self.cur_local_commitment_transaction_number == INITIAL_COMMITMENT_NUMBER - 1 &&
1534                                 self.cur_remote_commitment_transaction_number == INITIAL_COMMITMENT_NUMBER - 1 {
1535                         if self.their_cur_commitment_point != Some(msg.next_per_commitment_point) {
1536                                 return Err(ChannelError::Close("Peer sent a reconnect funding_locked with a different point"));
1537                         }
1538                         // They probably disconnected/reconnected and re-sent the funding_locked, which is required
1539                         return Ok(());
1540                 } else {
1541                         return Err(ChannelError::Close("Peer sent a funding_locked at a strange time"));
1542                 }
1543
1544                 self.their_prev_commitment_point = self.their_cur_commitment_point;
1545                 self.their_cur_commitment_point = Some(msg.next_per_commitment_point);
1546                 Ok(())
1547         }
1548
1549         /// Returns (inbound_htlc_count, htlc_inbound_value_msat)
1550         fn get_inbound_pending_htlc_stats(&self) -> (u32, u64) {
1551                 let mut htlc_inbound_value_msat = 0;
1552                 for ref htlc in self.pending_inbound_htlcs.iter() {
1553                         htlc_inbound_value_msat += htlc.amount_msat;
1554                 }
1555                 (self.pending_inbound_htlcs.len() as u32, htlc_inbound_value_msat)
1556         }
1557
1558         /// Returns (outbound_htlc_count, htlc_outbound_value_msat) *including* pending adds in our
1559         /// holding cell.
1560         fn get_outbound_pending_htlc_stats(&self) -> (u32, u64) {
1561                 let mut htlc_outbound_value_msat = 0;
1562                 for ref htlc in self.pending_outbound_htlcs.iter() {
1563                         htlc_outbound_value_msat += htlc.amount_msat;
1564                 }
1565
1566                 let mut htlc_outbound_count = self.pending_outbound_htlcs.len();
1567                 for update in self.holding_cell_htlc_updates.iter() {
1568                         if let &HTLCUpdateAwaitingACK::AddHTLC { ref amount_msat, .. } = update {
1569                                 htlc_outbound_count += 1;
1570                                 htlc_outbound_value_msat += amount_msat;
1571                         }
1572                 }
1573
1574                 (htlc_outbound_count as u32, htlc_outbound_value_msat)
1575         }
1576
1577         pub fn update_add_htlc(&mut self, msg: &msgs::UpdateAddHTLC, pending_forward_state: PendingHTLCStatus) -> Result<(), ChannelError> {
1578                 if (self.channel_state & (ChannelState::ChannelFunded as u32 | ChannelState::RemoteShutdownSent as u32)) != (ChannelState::ChannelFunded as u32) {
1579                         return Err(ChannelError::Close("Got add HTLC message when channel was not in an operational state"));
1580                 }
1581                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
1582                         return Err(ChannelError::Close("Peer sent update_add_htlc when we needed a channel_reestablish"));
1583                 }
1584                 if msg.amount_msat > self.channel_value_satoshis * 1000 {
1585                         return Err(ChannelError::Close("Remote side tried to send more than the total value of the channel"));
1586                 }
1587                 if msg.amount_msat < self.our_htlc_minimum_msat {
1588                         return Err(ChannelError::Close("Remote side tried to send less than our minimum HTLC value"));
1589                 }
1590
1591                 let (inbound_htlc_count, htlc_inbound_value_msat) = self.get_inbound_pending_htlc_stats();
1592                 if inbound_htlc_count + 1 > OUR_MAX_HTLCS as u32 {
1593                         return Err(ChannelError::Close("Remote tried to push more than our max accepted HTLCs"));
1594                 }
1595                 //TODO: Spec is unclear if this is per-direction or in total (I assume per direction):
1596                 // Check our_max_htlc_value_in_flight_msat
1597                 if htlc_inbound_value_msat + msg.amount_msat > Channel::get_our_max_htlc_value_in_flight_msat(self.channel_value_satoshis) {
1598                         return Err(ChannelError::Close("Remote HTLC add would put them over their max HTLC value in flight"));
1599                 }
1600                 // Check our_channel_reserve_satoshis (we're getting paid, so they have to at least meet
1601                 // the reserve_satoshis we told them to always have as direct payment so that they lose
1602                 // something if we punish them for broadcasting an old state).
1603                 // Note that we don't really care about having a small/no to_remote output in our local
1604                 // commitment transactions, as the purpose of the channel reserve is to ensure we can
1605                 // punish *them* if they misbehave, so we discount any outbound HTLCs which will not be
1606                 // present in the next commitment transaction we send them (at least for fulfilled ones,
1607                 // failed ones won't modify value_to_self).
1608                 // Note that we will send HTLCs which another instance of rust-lightning would think
1609                 // violate the reserve value if we do not do this (as we forget inbound HTLCs from the
1610                 // Channel state once they will not be present in the next received commitment
1611                 // transaction).
1612                 let mut removed_outbound_total_msat = 0;
1613                 for ref htlc in self.pending_outbound_htlcs.iter() {
1614                         if let OutboundHTLCState::AwaitingRemoteRevokeToRemove(None) = htlc.state {
1615                                 removed_outbound_total_msat += htlc.amount_msat;
1616                         } else if let OutboundHTLCState::AwaitingRemovedRemoteRevoke(None) = htlc.state {
1617                                 removed_outbound_total_msat += htlc.amount_msat;
1618                         }
1619                 }
1620                 if htlc_inbound_value_msat + msg.amount_msat + self.value_to_self_msat > (self.channel_value_satoshis - Channel::get_our_channel_reserve_satoshis(self.channel_value_satoshis)) * 1000 + removed_outbound_total_msat {
1621                         return Err(ChannelError::Close("Remote HTLC add would put them over their reserve value"));
1622                 }
1623                 if self.next_remote_htlc_id != msg.htlc_id {
1624                         return Err(ChannelError::Close("Remote skipped HTLC ID"));
1625                 }
1626                 if msg.cltv_expiry >= 500000000 {
1627                         return Err(ChannelError::Close("Remote provided CLTV expiry in seconds instead of block height"));
1628                 }
1629
1630                 //TODO: Check msg.cltv_expiry further? Do this in channel manager?
1631
1632                 if self.channel_state & ChannelState::LocalShutdownSent as u32 != 0 {
1633                         if let PendingHTLCStatus::Forward(_) = pending_forward_state {
1634                                 panic!("ChannelManager shouldn't be trying to add a forwardable HTLC after we've started closing");
1635                         }
1636                 }
1637
1638                 // Now update local state:
1639                 self.next_remote_htlc_id += 1;
1640                 self.pending_inbound_htlcs.push(InboundHTLCOutput {
1641                         htlc_id: msg.htlc_id,
1642                         amount_msat: msg.amount_msat,
1643                         payment_hash: msg.payment_hash,
1644                         cltv_expiry: msg.cltv_expiry,
1645                         state: InboundHTLCState::RemoteAnnounced(pending_forward_state),
1646                 });
1647                 Ok(())
1648         }
1649
1650         /// Marks an outbound HTLC which we have received update_fail/fulfill/malformed
1651         #[inline]
1652         fn mark_outbound_htlc_removed(&mut self, htlc_id: u64, check_preimage: Option<PaymentHash>, fail_reason: Option<HTLCFailReason>) -> Result<&HTLCSource, ChannelError> {
1653                 for htlc in self.pending_outbound_htlcs.iter_mut() {
1654                         if htlc.htlc_id == htlc_id {
1655                                 match check_preimage {
1656                                         None => {},
1657                                         Some(payment_hash) =>
1658                                                 if payment_hash != htlc.payment_hash {
1659                                                         return Err(ChannelError::Close("Remote tried to fulfill HTLC with an incorrect preimage"));
1660                                                 }
1661                                 };
1662                                 match htlc.state {
1663                                         OutboundHTLCState::LocalAnnounced(_) =>
1664                                                 return Err(ChannelError::Close("Remote tried to fulfill/fail HTLC before it had been committed")),
1665                                         OutboundHTLCState::Committed => {
1666                                                 htlc.state = OutboundHTLCState::RemoteRemoved(fail_reason);
1667                                         },
1668                                         OutboundHTLCState::AwaitingRemoteRevokeToRemove(_) | OutboundHTLCState::AwaitingRemovedRemoteRevoke(_) | OutboundHTLCState::RemoteRemoved(_) =>
1669                                                 return Err(ChannelError::Close("Remote tried to fulfill/fail HTLC that they'd already fulfilled/failed")),
1670                                 }
1671                                 return Ok(&htlc.source);
1672                         }
1673                 }
1674                 Err(ChannelError::Close("Remote tried to fulfill/fail an HTLC we couldn't find"))
1675         }
1676
1677         pub fn update_fulfill_htlc(&mut self, msg: &msgs::UpdateFulfillHTLC) -> Result<HTLCSource, ChannelError> {
1678                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
1679                         return Err(ChannelError::Close("Got fulfill HTLC message when channel was not in an operational state"));
1680                 }
1681                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
1682                         return Err(ChannelError::Close("Peer sent update_fulfill_htlc when we needed a channel_reestablish"));
1683                 }
1684
1685                 let payment_hash = PaymentHash(Sha256::hash(&msg.payment_preimage.0[..]).into_inner());
1686                 self.mark_outbound_htlc_removed(msg.htlc_id, Some(payment_hash), None).map(|source| source.clone())
1687         }
1688
1689         pub fn update_fail_htlc(&mut self, msg: &msgs::UpdateFailHTLC, fail_reason: HTLCFailReason) -> Result<(), ChannelError> {
1690                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
1691                         return Err(ChannelError::Close("Got fail HTLC message when channel was not in an operational state"));
1692                 }
1693                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
1694                         return Err(ChannelError::Close("Peer sent update_fail_htlc when we needed a channel_reestablish"));
1695                 }
1696
1697                 self.mark_outbound_htlc_removed(msg.htlc_id, None, Some(fail_reason))?;
1698                 Ok(())
1699         }
1700
1701         pub fn update_fail_malformed_htlc<'a>(&mut self, msg: &msgs::UpdateFailMalformedHTLC, fail_reason: HTLCFailReason) -> Result<(), ChannelError> {
1702                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
1703                         return Err(ChannelError::Close("Got fail malformed HTLC message when channel was not in an operational state"));
1704                 }
1705                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
1706                         return Err(ChannelError::Close("Peer sent update_fail_malformed_htlc when we needed a channel_reestablish"));
1707                 }
1708
1709                 self.mark_outbound_htlc_removed(msg.htlc_id, None, Some(fail_reason))?;
1710                 Ok(())
1711         }
1712
1713         pub fn commitment_signed(&mut self, msg: &msgs::CommitmentSigned, fee_estimator: &FeeEstimator) -> Result<(msgs::RevokeAndACK, Option<msgs::CommitmentSigned>, Option<msgs::ClosingSigned>, ChannelMonitor), ChannelError> {
1714                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
1715                         return Err(ChannelError::Close("Got commitment signed message when channel was not in an operational state"));
1716                 }
1717                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
1718                         return Err(ChannelError::Close("Peer sent commitment_signed when we needed a channel_reestablish"));
1719                 }
1720                 if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK == BOTH_SIDES_SHUTDOWN_MASK && self.last_sent_closing_fee.is_some() {
1721                         return Err(ChannelError::Close("Peer sent commitment_signed after we'd started exchanging closing_signeds"));
1722                 }
1723
1724                 let funding_script = self.get_funding_redeemscript();
1725
1726                 let local_keys = self.build_local_transaction_keys(self.cur_local_commitment_transaction_number)?;
1727
1728                 let mut update_fee = false;
1729                 let feerate_per_kw = if !self.channel_outbound && self.pending_update_fee.is_some() {
1730                         update_fee = true;
1731                         self.pending_update_fee.unwrap()
1732                 } else {
1733                         self.feerate_per_kw
1734                 };
1735
1736                 let mut local_commitment_tx = {
1737                         let mut commitment_tx = self.build_commitment_transaction(self.cur_local_commitment_transaction_number, &local_keys, true, false, feerate_per_kw);
1738                         let htlcs_cloned: Vec<_> = commitment_tx.2.drain(..).map(|htlc| (htlc.0, htlc.1.map(|h| h.clone()))).collect();
1739                         (commitment_tx.0, commitment_tx.1, htlcs_cloned)
1740                 };
1741                 let local_commitment_txid = local_commitment_tx.0.txid();
1742                 let local_sighash = hash_to_message!(&bip143::SighashComponents::new(&local_commitment_tx.0).sighash_all(&local_commitment_tx.0.input[0], &funding_script, self.channel_value_satoshis)[..]);
1743                 log_trace!(self, "Checking commitment tx signature {} by key {} against tx {} with redeemscript {}", log_bytes!(msg.signature.serialize_compact()[..]), log_bytes!(self.their_funding_pubkey.unwrap().serialize()), encode::serialize_hex(&local_commitment_tx.0), encode::serialize_hex(&funding_script));
1744                 secp_check!(self.secp_ctx.verify(&local_sighash, &msg.signature, &self.their_funding_pubkey.unwrap()), "Invalid commitment tx signature from peer");
1745
1746                 //If channel fee was updated by funder confirm funder can afford the new fee rate when applied to the current local commitment transaction
1747                 if update_fee {
1748                         let num_htlcs = local_commitment_tx.1;
1749                         let total_fee: u64 = feerate_per_kw as u64 * (COMMITMENT_TX_BASE_WEIGHT + (num_htlcs as u64) * COMMITMENT_TX_WEIGHT_PER_HTLC) / 1000;
1750
1751                         if self.channel_value_satoshis - self.value_to_self_msat / 1000 < total_fee + self.their_channel_reserve_satoshis {
1752                                 return Err(ChannelError::Close("Funding remote cannot afford proposed new fee"));
1753                         }
1754                 }
1755
1756                 if msg.htlc_signatures.len() != local_commitment_tx.1 {
1757                         return Err(ChannelError::Close("Got wrong number of HTLC signatures from remote"));
1758                 }
1759
1760                 let mut new_local_commitment_txn = Vec::with_capacity(local_commitment_tx.1 + 1);
1761                 self.sign_commitment_transaction(&mut local_commitment_tx.0, &msg.signature);
1762                 new_local_commitment_txn.push(local_commitment_tx.0.clone());
1763
1764                 let mut htlcs_and_sigs = Vec::with_capacity(local_commitment_tx.2.len());
1765                 for (idx, (htlc, source)) in local_commitment_tx.2.drain(..).enumerate() {
1766                         if let Some(_) = htlc.transaction_output_index {
1767                                 let mut htlc_tx = self.build_htlc_transaction(&local_commitment_txid, &htlc, true, &local_keys, feerate_per_kw);
1768                                 let htlc_redeemscript = chan_utils::get_htlc_redeemscript(&htlc, &local_keys);
1769                                 log_trace!(self, "Checking HTLC tx signature {} by key {} against tx {} with redeemscript {}", log_bytes!(msg.htlc_signatures[idx].serialize_compact()[..]), log_bytes!(local_keys.b_htlc_key.serialize()), encode::serialize_hex(&htlc_tx), encode::serialize_hex(&htlc_redeemscript));
1770                                 let htlc_sighash = hash_to_message!(&bip143::SighashComponents::new(&htlc_tx).sighash_all(&htlc_tx.input[0], &htlc_redeemscript, htlc.amount_msat / 1000)[..]);
1771                                 secp_check!(self.secp_ctx.verify(&htlc_sighash, &msg.htlc_signatures[idx], &local_keys.b_htlc_key), "Invalid HTLC tx signature from peer");
1772                                 let htlc_sig = if htlc.offered {
1773                                         let htlc_sig = self.sign_htlc_transaction(&mut htlc_tx, &msg.htlc_signatures[idx], &None, &htlc, &local_keys)?;
1774                                         new_local_commitment_txn.push(htlc_tx);
1775                                         htlc_sig
1776                                 } else {
1777                                         self.create_htlc_tx_signature(&htlc_tx, &htlc, &local_keys)?.1
1778                                 };
1779                                 htlcs_and_sigs.push((htlc, Some((msg.htlc_signatures[idx], htlc_sig)), source));
1780                         } else {
1781                                 htlcs_and_sigs.push((htlc, None, source));
1782                         }
1783                 }
1784
1785                 let next_per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &self.build_local_commitment_secret(self.cur_local_commitment_transaction_number - 1));
1786                 let per_commitment_secret = chan_utils::build_commitment_secret(self.local_keys.commitment_seed, self.cur_local_commitment_transaction_number + 1);
1787
1788                 // Update state now that we've passed all the can-fail calls...
1789                 let mut need_our_commitment = false;
1790                 if !self.channel_outbound {
1791                         if let Some(fee_update) = self.pending_update_fee {
1792                                 self.feerate_per_kw = fee_update;
1793                                 // We later use the presence of pending_update_fee to indicate we should generate a
1794                                 // commitment_signed upon receipt of revoke_and_ack, so we can only set it to None
1795                                 // if we're not awaiting a revoke (ie will send a commitment_signed now).
1796                                 if (self.channel_state & ChannelState::AwaitingRemoteRevoke as u32) == 0 {
1797                                         need_our_commitment = true;
1798                                         self.pending_update_fee = None;
1799                                 }
1800                         }
1801                 }
1802
1803                 if self.channel_state & (ChannelState::MonitorUpdateFailed as u32) == 0 {
1804                         // This is a response to our post-monitor-failed unfreeze messages, so we can clear the
1805                         // monitor_pending_order requirement as we won't re-send the monitor_pending messages.
1806                         self.monitor_pending_order = None;
1807                 }
1808
1809                 self.channel_monitor.provide_latest_local_commitment_tx_info(local_commitment_tx.0, local_keys, self.feerate_per_kw, htlcs_and_sigs);
1810
1811                 for htlc in self.pending_inbound_htlcs.iter_mut() {
1812                         let new_forward = if let &InboundHTLCState::RemoteAnnounced(ref forward_info) = &htlc.state {
1813                                 Some(forward_info.clone())
1814                         } else { None };
1815                         if let Some(forward_info) = new_forward {
1816                                 htlc.state = InboundHTLCState::AwaitingRemoteRevokeToAnnounce(forward_info);
1817                                 need_our_commitment = true;
1818                         }
1819                 }
1820                 for htlc in self.pending_outbound_htlcs.iter_mut() {
1821                         if let Some(fail_reason) = if let &mut OutboundHTLCState::RemoteRemoved(ref mut fail_reason) = &mut htlc.state {
1822                                 Some(fail_reason.take())
1823                         } else { None } {
1824                                 htlc.state = OutboundHTLCState::AwaitingRemoteRevokeToRemove(fail_reason);
1825                                 need_our_commitment = true;
1826                         }
1827                 }
1828
1829                 self.cur_local_commitment_transaction_number -= 1;
1830                 self.last_local_commitment_txn = new_local_commitment_txn;
1831                 self.received_commitment_while_awaiting_raa = (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) != 0;
1832
1833                 if (self.channel_state & ChannelState::MonitorUpdateFailed as u32) != 0 {
1834                         // In case we initially failed monitor updating without requiring a response, we need
1835                         // to make sure the RAA gets sent first.
1836                         if !self.monitor_pending_commitment_signed {
1837                                 self.monitor_pending_order = Some(RAACommitmentOrder::RevokeAndACKFirst);
1838                         }
1839                         self.monitor_pending_revoke_and_ack = true;
1840                         if need_our_commitment && (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == 0 {
1841                                 // If we were going to send a commitment_signed after the RAA, go ahead and do all
1842                                 // the corresponding HTLC status updates so that get_last_commitment_update
1843                                 // includes the right HTLCs.
1844                                 // Note that this generates a monitor update that we ignore! This is OK since we
1845                                 // won't actually send the commitment_signed that generated the update to the other
1846                                 // side until the latest monitor has been pulled from us and stored.
1847                                 self.monitor_pending_commitment_signed = true;
1848                                 self.send_commitment_no_status_check()?;
1849                         }
1850                         // TODO: Call maybe_propose_first_closing_signed on restoration (or call it here and
1851                         // re-send the message on restoration)
1852                         return Err(ChannelError::Ignore("Previous monitor update failure prevented generation of RAA"));
1853                 }
1854
1855                 let (our_commitment_signed, monitor_update, closing_signed) = if need_our_commitment && (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == 0 {
1856                         // If we're AwaitingRemoteRevoke we can't send a new commitment here, but that's ok -
1857                         // we'll send one right away when we get the revoke_and_ack when we
1858                         // free_holding_cell_htlcs().
1859                         let (msg, monitor) = self.send_commitment_no_status_check()?;
1860                         (Some(msg), monitor, None)
1861                 } else if !need_our_commitment {
1862                         (None, self.channel_monitor.clone(), self.maybe_propose_first_closing_signed(fee_estimator))
1863                 } else { (None, self.channel_monitor.clone(), None) };
1864
1865                 Ok((msgs::RevokeAndACK {
1866                         channel_id: self.channel_id,
1867                         per_commitment_secret: per_commitment_secret,
1868                         next_per_commitment_point: next_per_commitment_point,
1869                 }, our_commitment_signed, closing_signed, monitor_update))
1870         }
1871
1872         /// Used to fulfill holding_cell_htlcs when we get a remote ack (or implicitly get it by them
1873         /// fulfilling or failing the last pending HTLC)
1874         fn free_holding_cell_htlcs(&mut self) -> Result<Option<(msgs::CommitmentUpdate, ChannelMonitor)>, ChannelError> {
1875                 assert_eq!(self.channel_state & ChannelState::MonitorUpdateFailed as u32, 0);
1876                 if self.holding_cell_htlc_updates.len() != 0 || self.holding_cell_update_fee.is_some() {
1877                         log_trace!(self, "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 { "" });
1878
1879                         let mut htlc_updates = Vec::new();
1880                         mem::swap(&mut htlc_updates, &mut self.holding_cell_htlc_updates);
1881                         let mut update_add_htlcs = Vec::with_capacity(htlc_updates.len());
1882                         let mut update_fulfill_htlcs = Vec::with_capacity(htlc_updates.len());
1883                         let mut update_fail_htlcs = Vec::with_capacity(htlc_updates.len());
1884                         let mut err = None;
1885                         for htlc_update in htlc_updates.drain(..) {
1886                                 // Note that this *can* fail, though it should be due to rather-rare conditions on
1887                                 // fee races with adding too many outputs which push our total payments just over
1888                                 // the limit. In case it's less rare than I anticipate, we may want to revisit
1889                                 // handling this case better and maybe fulfilling some of the HTLCs while attempting
1890                                 // to rebalance channels.
1891                                 if err.is_some() { // We're back to AwaitingRemoteRevoke (or are about to fail the channel)
1892                                         self.holding_cell_htlc_updates.push(htlc_update);
1893                                 } else {
1894                                         match &htlc_update {
1895                                                 &HTLCUpdateAwaitingACK::AddHTLC {amount_msat, cltv_expiry, ref payment_hash, ref source, ref onion_routing_packet, ..} => {
1896                                                         match self.send_htlc(amount_msat, *payment_hash, cltv_expiry, source.clone(), onion_routing_packet.clone()) {
1897                                                                 Ok(update_add_msg_option) => update_add_htlcs.push(update_add_msg_option.unwrap()),
1898                                                                 Err(e) => {
1899                                                                         match e {
1900                                                                                 ChannelError::Ignore(ref msg) => {
1901                                                                                         log_info!(self, "Failed to send HTLC with payment_hash {} due to {}", log_bytes!(payment_hash.0), msg);
1902                                                                                 },
1903                                                                                 _ => {
1904                                                                                         log_info!(self, "Failed to send HTLC with payment_hash {} resulting in a channel closure during holding_cell freeing", log_bytes!(payment_hash.0));
1905                                                                                 },
1906                                                                         }
1907                                                                         err = Some(e);
1908                                                                 }
1909                                                         }
1910                                                 },
1911                                                 &HTLCUpdateAwaitingACK::ClaimHTLC { ref payment_preimage, htlc_id, .. } => {
1912                                                         match self.get_update_fulfill_htlc(htlc_id, *payment_preimage) {
1913                                                                 Ok(update_fulfill_msg_option) => update_fulfill_htlcs.push(update_fulfill_msg_option.0.unwrap()),
1914                                                                 Err(e) => {
1915                                                                         if let ChannelError::Ignore(_) = e {}
1916                                                                         else {
1917                                                                                 panic!("Got a non-IgnoreError action trying to fulfill holding cell HTLC");
1918                                                                         }
1919                                                                 }
1920                                                         }
1921                                                 },
1922                                                 &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, ref err_packet } => {
1923                                                         match self.get_update_fail_htlc(htlc_id, err_packet.clone()) {
1924                                                                 Ok(update_fail_msg_option) => update_fail_htlcs.push(update_fail_msg_option.unwrap()),
1925                                                                 Err(e) => {
1926                                                                         if let ChannelError::Ignore(_) = e {}
1927                                                                         else {
1928                                                                                 panic!("Got a non-IgnoreError action trying to fail holding cell HTLC");
1929                                                                         }
1930                                                                 }
1931                                                         }
1932                                                 },
1933                                         }
1934                                         if err.is_some() {
1935                                                 self.holding_cell_htlc_updates.push(htlc_update);
1936                                                 if let Some(ChannelError::Ignore(_)) = err {
1937                                                         // If we failed to add the HTLC, but got an Ignore error, we should
1938                                                         // still send the new commitment_signed, so reset the err to None.
1939                                                         err = None;
1940                                                 }
1941                                         }
1942                                 }
1943                         }
1944                         //TODO: Need to examine the type of err - if it's a fee issue or similar we may want to
1945                         //fail it back the route, if it's a temporary issue we can ignore it...
1946                         match err {
1947                                 None => {
1948                                         if update_add_htlcs.is_empty() && update_fulfill_htlcs.is_empty() && update_fail_htlcs.is_empty() && self.holding_cell_update_fee.is_none() {
1949                                                 // This should never actually happen and indicates we got some Errs back
1950                                                 // from update_fulfill_htlc/update_fail_htlc, but we handle it anyway in
1951                                                 // case there is some strange way to hit duplicate HTLC removes.
1952                                                 return Ok(None);
1953                                         }
1954                                         let update_fee = if let Some(feerate) = self.holding_cell_update_fee {
1955                                                         self.pending_update_fee = self.holding_cell_update_fee.take();
1956                                                         Some(msgs::UpdateFee {
1957                                                                 channel_id: self.channel_id,
1958                                                                 feerate_per_kw: feerate as u32,
1959                                                         })
1960                                                 } else {
1961                                                         None
1962                                                 };
1963                                         let (commitment_signed, monitor_update) = self.send_commitment_no_status_check()?;
1964                                         Ok(Some((msgs::CommitmentUpdate {
1965                                                 update_add_htlcs,
1966                                                 update_fulfill_htlcs,
1967                                                 update_fail_htlcs,
1968                                                 update_fail_malformed_htlcs: Vec::new(),
1969                                                 update_fee: update_fee,
1970                                                 commitment_signed,
1971                                         }, monitor_update)))
1972                                 },
1973                                 Some(e) => Err(e)
1974                         }
1975                 } else {
1976                         Ok(None)
1977                 }
1978         }
1979
1980         /// Handles receiving a remote's revoke_and_ack. Note that we may return a new
1981         /// commitment_signed message here in case we had pending outbound HTLCs to add which were
1982         /// waiting on this revoke_and_ack. The generation of this new commitment_signed may also fail,
1983         /// generating an appropriate error *after* the channel state has been updated based on the
1984         /// revoke_and_ack message.
1985         pub fn revoke_and_ack(&mut self, msg: &msgs::RevokeAndACK, fee_estimator: &FeeEstimator) -> Result<(Option<msgs::CommitmentUpdate>, Vec<(PendingForwardHTLCInfo, u64)>, Vec<(HTLCSource, PaymentHash, HTLCFailReason)>, Option<msgs::ClosingSigned>, ChannelMonitor), ChannelError> {
1986                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
1987                         return Err(ChannelError::Close("Got revoke/ACK message when channel was not in an operational state"));
1988                 }
1989                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
1990                         return Err(ChannelError::Close("Peer sent revoke_and_ack when we needed a channel_reestablish"));
1991                 }
1992                 if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK == BOTH_SIDES_SHUTDOWN_MASK && self.last_sent_closing_fee.is_some() {
1993                         return Err(ChannelError::Close("Peer sent revoke_and_ack after we'd started exchanging closing_signeds"));
1994                 }
1995
1996                 if let Some(their_prev_commitment_point) = self.their_prev_commitment_point {
1997                         if PublicKey::from_secret_key(&self.secp_ctx, &secp_check!(SecretKey::from_slice(&msg.per_commitment_secret), "Peer provided an invalid per_commitment_secret")) != their_prev_commitment_point {
1998                                 return Err(ChannelError::Close("Got a revoke commitment secret which didn't correspond to their current pubkey"));
1999                         }
2000                 }
2001                 self.channel_monitor.provide_secret(self.cur_remote_commitment_transaction_number + 1, msg.per_commitment_secret)
2002                         .map_err(|e| ChannelError::Close(e.0))?;
2003
2004                 // Update state now that we've passed all the can-fail calls...
2005                 // (note that we may still fail to generate the new commitment_signed message, but that's
2006                 // OK, we step the channel here and *then* if the new generation fails we can fail the
2007                 // channel based on that, but stepping stuff here should be safe either way.
2008                 self.channel_state &= !(ChannelState::AwaitingRemoteRevoke as u32);
2009                 self.their_prev_commitment_point = self.their_cur_commitment_point;
2010                 self.their_cur_commitment_point = Some(msg.next_per_commitment_point);
2011                 self.cur_remote_commitment_transaction_number -= 1;
2012                 self.received_commitment_while_awaiting_raa = false;
2013                 if self.channel_state & (ChannelState::MonitorUpdateFailed as u32) == 0 {
2014                         // This is a response to our post-monitor-failed unfreeze messages, so we can clear the
2015                         // monitor_pending_order requirement as we won't re-send the monitor_pending messages.
2016                         self.monitor_pending_order = None;
2017                 }
2018
2019                 log_trace!(self, "Updating HTLCs on receipt of RAA...");
2020                 let mut to_forward_infos = Vec::new();
2021                 let mut revoked_htlcs = Vec::new();
2022                 let mut update_fail_htlcs = Vec::new();
2023                 let mut update_fail_malformed_htlcs = Vec::new();
2024                 let mut require_commitment = false;
2025                 let mut value_to_self_msat_diff: i64 = 0;
2026
2027                 {
2028                         // Take references explicitly so that we can hold multiple references to self.
2029                         let pending_inbound_htlcs: &mut Vec<_> = &mut self.pending_inbound_htlcs;
2030                         let pending_outbound_htlcs: &mut Vec<_> = &mut self.pending_outbound_htlcs;
2031                         let logger = LogHolder { logger: &self.logger };
2032
2033                         // We really shouldnt have two passes here, but retain gives a non-mutable ref (Rust bug)
2034                         pending_inbound_htlcs.retain(|htlc| {
2035                                 if let &InboundHTLCState::LocalRemoved(ref reason) = &htlc.state {
2036                                         log_trace!(logger, " ...removing inbound LocalRemoved {}", log_bytes!(htlc.payment_hash.0));
2037                                         if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
2038                                                 value_to_self_msat_diff += htlc.amount_msat as i64;
2039                                         }
2040                                         false
2041                                 } else { true }
2042                         });
2043                         pending_outbound_htlcs.retain(|htlc| {
2044                                 if let &OutboundHTLCState::AwaitingRemovedRemoteRevoke(ref fail_reason) = &htlc.state {
2045                                         log_trace!(logger, " ...removing outbound AwaitingRemovedRemoteRevoke {}", log_bytes!(htlc.payment_hash.0));
2046                                         if let Some(reason) = fail_reason.clone() { // We really want take() here, but, again, non-mut ref :(
2047                                                 revoked_htlcs.push((htlc.source.clone(), htlc.payment_hash, reason));
2048                                         } else {
2049                                                 // They fulfilled, so we sent them money
2050                                                 value_to_self_msat_diff -= htlc.amount_msat as i64;
2051                                         }
2052                                         false
2053                                 } else { true }
2054                         });
2055                         for htlc in pending_inbound_htlcs.iter_mut() {
2056                                 let swap = if let &InboundHTLCState::AwaitingRemoteRevokeToAnnounce(_) = &htlc.state {
2057                                         log_trace!(logger, " ...promoting inbound AwaitingRemoteRevokeToAnnounce {} to Committed", log_bytes!(htlc.payment_hash.0));
2058                                         true
2059                                 } else if let &InboundHTLCState::AwaitingAnnouncedRemoteRevoke(_) = &htlc.state {
2060                                         log_trace!(logger, " ...promoting inbound AwaitingAnnouncedRemoteRevoke {} to Committed", log_bytes!(htlc.payment_hash.0));
2061                                         true
2062                                 } else { false };
2063                                 if swap {
2064                                         let mut state = InboundHTLCState::Committed;
2065                                         mem::swap(&mut state, &mut htlc.state);
2066
2067                                         if let InboundHTLCState::AwaitingRemoteRevokeToAnnounce(forward_info) = state {
2068                                                 htlc.state = InboundHTLCState::AwaitingAnnouncedRemoteRevoke(forward_info);
2069                                                 require_commitment = true;
2070                                         } else if let InboundHTLCState::AwaitingAnnouncedRemoteRevoke(forward_info) = state {
2071                                                 match forward_info {
2072                                                         PendingHTLCStatus::Fail(fail_msg) => {
2073                                                                 require_commitment = true;
2074                                                                 match fail_msg {
2075                                                                         HTLCFailureMsg::Relay(msg) => {
2076                                                                                 htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::FailRelay(msg.reason.clone()));
2077                                                                                 update_fail_htlcs.push(msg)
2078                                                                         },
2079                                                                         HTLCFailureMsg::Malformed(msg) => {
2080                                                                                 htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::FailMalformed((msg.sha256_of_onion, msg.failure_code)));
2081                                                                                 update_fail_malformed_htlcs.push(msg)
2082                                                                         },
2083                                                                 }
2084                                                         },
2085                                                         PendingHTLCStatus::Forward(forward_info) => {
2086                                                                 to_forward_infos.push((forward_info, htlc.htlc_id));
2087                                                                 htlc.state = InboundHTLCState::Committed;
2088                                                         }
2089                                                 }
2090                                         }
2091                                 }
2092                         }
2093                         for htlc in pending_outbound_htlcs.iter_mut() {
2094                                 if let OutboundHTLCState::LocalAnnounced(_) = htlc.state {
2095                                         log_trace!(logger, " ...promoting outbound LocalAnnounced {} to Committed", log_bytes!(htlc.payment_hash.0));
2096                                         htlc.state = OutboundHTLCState::Committed;
2097                                 }
2098                                 if let Some(fail_reason) = if let &mut OutboundHTLCState::AwaitingRemoteRevokeToRemove(ref mut fail_reason) = &mut htlc.state {
2099                                         Some(fail_reason.take())
2100                                 } else { None } {
2101                                         log_trace!(logger, " ...promoting outbound AwaitingRemoteRevokeToRemove {} to AwaitingRemovedRemoteRevoke", log_bytes!(htlc.payment_hash.0));
2102                                         htlc.state = OutboundHTLCState::AwaitingRemovedRemoteRevoke(fail_reason);
2103                                         require_commitment = true;
2104                                 }
2105                         }
2106                 }
2107                 self.value_to_self_msat = (self.value_to_self_msat as i64 + value_to_self_msat_diff) as u64;
2108
2109                 if self.channel_outbound {
2110                         if let Some(feerate) = self.pending_update_fee.take() {
2111                                 self.feerate_per_kw = feerate;
2112                         }
2113                 } else {
2114                         if let Some(feerate) = self.pending_update_fee {
2115                                 // Because a node cannot send two commitment_signeds in a row without getting a
2116                                 // revoke_and_ack from us (as it would otherwise not know the per_commitment_point
2117                                 // it should use to create keys with) and because a node can't send a
2118                                 // commitment_signed without changes, checking if the feerate is equal to the
2119                                 // pending feerate update is sufficient to detect require_commitment.
2120                                 if feerate == self.feerate_per_kw {
2121                                         require_commitment = true;
2122                                         self.pending_update_fee = None;
2123                                 }
2124                         }
2125                 }
2126
2127                 if (self.channel_state & ChannelState::MonitorUpdateFailed as u32) == ChannelState::MonitorUpdateFailed as u32 {
2128                         // We can't actually generate a new commitment transaction (incl by freeing holding
2129                         // cells) while we can't update the monitor, so we just return what we have.
2130                         if require_commitment {
2131                                 self.monitor_pending_commitment_signed = true;
2132                                 // When the monitor updating is restored we'll call get_last_commitment_update(),
2133                                 // which does not update state, but we're definitely now awaiting a remote revoke
2134                                 // before we can step forward any more, so set it here.
2135                                 self.channel_state |= ChannelState::AwaitingRemoteRevoke as u32;
2136                         }
2137                         self.monitor_pending_forwards.append(&mut to_forward_infos);
2138                         self.monitor_pending_failures.append(&mut revoked_htlcs);
2139                         return Ok((None, Vec::new(), Vec::new(), None, self.channel_monitor.clone()));
2140                 }
2141
2142                 match self.free_holding_cell_htlcs()? {
2143                         Some(mut commitment_update) => {
2144                                 commitment_update.0.update_fail_htlcs.reserve(update_fail_htlcs.len());
2145                                 for fail_msg in update_fail_htlcs.drain(..) {
2146                                         commitment_update.0.update_fail_htlcs.push(fail_msg);
2147                                 }
2148                                 commitment_update.0.update_fail_malformed_htlcs.reserve(update_fail_malformed_htlcs.len());
2149                                 for fail_msg in update_fail_malformed_htlcs.drain(..) {
2150                                         commitment_update.0.update_fail_malformed_htlcs.push(fail_msg);
2151                                 }
2152                                 Ok((Some(commitment_update.0), to_forward_infos, revoked_htlcs, None, commitment_update.1))
2153                         },
2154                         None => {
2155                                 if require_commitment {
2156                                         let (commitment_signed, monitor_update) = self.send_commitment_no_status_check()?;
2157                                         Ok((Some(msgs::CommitmentUpdate {
2158                                                 update_add_htlcs: Vec::new(),
2159                                                 update_fulfill_htlcs: Vec::new(),
2160                                                 update_fail_htlcs,
2161                                                 update_fail_malformed_htlcs,
2162                                                 update_fee: None,
2163                                                 commitment_signed
2164                                         }), to_forward_infos, revoked_htlcs, None, monitor_update))
2165                                 } else {
2166                                         Ok((None, to_forward_infos, revoked_htlcs, self.maybe_propose_first_closing_signed(fee_estimator), self.channel_monitor.clone()))
2167                                 }
2168                         }
2169                 }
2170
2171         }
2172
2173         /// Adds a pending update to this channel. See the doc for send_htlc for
2174         /// further details on the optionness of the return value.
2175         /// You MUST call send_commitment prior to any other calls on this Channel
2176         fn send_update_fee(&mut self, feerate_per_kw: u64) -> Option<msgs::UpdateFee> {
2177                 if !self.channel_outbound {
2178                         panic!("Cannot send fee from inbound channel");
2179                 }
2180                 if !self.is_usable() {
2181                         panic!("Cannot update fee until channel is fully established and we haven't started shutting down");
2182                 }
2183                 if !self.is_live() {
2184                         panic!("Cannot update fee while peer is disconnected/we're awaiting a monitor update (ChannelManager should have caught this)");
2185                 }
2186
2187                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == (ChannelState::AwaitingRemoteRevoke as u32) {
2188                         self.holding_cell_update_fee = Some(feerate_per_kw);
2189                         return None;
2190                 }
2191
2192                 debug_assert!(self.pending_update_fee.is_none());
2193                 self.pending_update_fee = Some(feerate_per_kw);
2194
2195                 Some(msgs::UpdateFee {
2196                         channel_id: self.channel_id,
2197                         feerate_per_kw: feerate_per_kw as u32,
2198                 })
2199         }
2200
2201         pub fn send_update_fee_and_commit(&mut self, feerate_per_kw: u64) -> Result<Option<(msgs::UpdateFee, msgs::CommitmentSigned, ChannelMonitor)>, ChannelError> {
2202                 match self.send_update_fee(feerate_per_kw) {
2203                         Some(update_fee) => {
2204                                 let (commitment_signed, monitor_update) = self.send_commitment_no_status_check()?;
2205                                 Ok(Some((update_fee, commitment_signed, monitor_update)))
2206                         },
2207                         None => Ok(None)
2208                 }
2209         }
2210
2211         /// Removes any uncommitted HTLCs, to be used on peer disconnection, including any pending
2212         /// HTLCs that we intended to add but haven't as we were waiting on a remote revoke.
2213         /// Returns the set of PendingHTLCStatuses from remote uncommitted HTLCs (which we're
2214         /// implicitly dropping) and the payment_hashes of HTLCs we tried to add but are dropping.
2215         /// No further message handling calls may be made until a channel_reestablish dance has
2216         /// completed.
2217         pub fn remove_uncommitted_htlcs_and_mark_paused(&mut self) -> Vec<(HTLCSource, PaymentHash)> {
2218                 let mut outbound_drops = Vec::new();
2219
2220                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
2221                 if self.channel_state < ChannelState::FundingSent as u32 {
2222                         self.channel_state = ChannelState::ShutdownComplete as u32;
2223                         return outbound_drops;
2224                 }
2225                 // Upon reconnect we have to start the closing_signed dance over, but shutdown messages
2226                 // will be retransmitted.
2227                 self.last_sent_closing_fee = None;
2228
2229                 let mut inbound_drop_count = 0;
2230                 self.pending_inbound_htlcs.retain(|htlc| {
2231                         match htlc.state {
2232                                 InboundHTLCState::RemoteAnnounced(_) => {
2233                                         // They sent us an update_add_htlc but we never got the commitment_signed.
2234                                         // We'll tell them what commitment_signed we're expecting next and they'll drop
2235                                         // this HTLC accordingly
2236                                         inbound_drop_count += 1;
2237                                         false
2238                                 },
2239                                 InboundHTLCState::AwaitingRemoteRevokeToAnnounce(_)|InboundHTLCState::AwaitingAnnouncedRemoteRevoke(_) => {
2240                                         // We received a commitment_signed updating this HTLC and (at least hopefully)
2241                                         // sent a revoke_and_ack (which we can re-transmit) and have heard nothing
2242                                         // in response to it yet, so don't touch it.
2243                                         true
2244                                 },
2245                                 InboundHTLCState::Committed => true,
2246                                 InboundHTLCState::LocalRemoved(_) => {
2247                                         // We (hopefully) sent a commitment_signed updating this HTLC (which we can
2248                                         // re-transmit if needed) and they may have even sent a revoke_and_ack back
2249                                         // (that we missed). Keep this around for now and if they tell us they missed
2250                                         // the commitment_signed we can re-transmit the update then.
2251                                         true
2252                                 },
2253                         }
2254                 });
2255                 self.next_remote_htlc_id -= inbound_drop_count;
2256
2257                 for htlc in self.pending_outbound_htlcs.iter_mut() {
2258                         if let OutboundHTLCState::RemoteRemoved(_) = htlc.state {
2259                                 // They sent us an update to remove this but haven't yet sent the corresponding
2260                                 // commitment_signed, we need to move it back to Committed and they can re-send
2261                                 // the update upon reconnection.
2262                                 htlc.state = OutboundHTLCState::Committed;
2263                         }
2264                 }
2265
2266                 self.holding_cell_htlc_updates.retain(|htlc_update| {
2267                         match htlc_update {
2268                                 &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, ref source, .. } => {
2269                                         outbound_drops.push((source.clone(), payment_hash.clone()));
2270                                         false
2271                                 },
2272                                 &HTLCUpdateAwaitingACK::ClaimHTLC {..} | &HTLCUpdateAwaitingACK::FailHTLC {..} => true,
2273                         }
2274                 });
2275                 self.channel_state |= ChannelState::PeerDisconnected as u32;
2276                 log_debug!(self, "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()));
2277                 outbound_drops
2278         }
2279
2280         /// Indicates that a ChannelMonitor update failed to be stored by the client and further
2281         /// updates are partially paused.
2282         /// This must be called immediately after the call which generated the ChannelMonitor update
2283         /// which failed, with the order argument set to the type of call it represented (ie a
2284         /// commitment update or a revoke_and_ack generation). The messages which were generated from
2285         /// that original call must *not* have been sent to the remote end, and must instead have been
2286         /// dropped. They will be regenerated when monitor_updating_restored is called.
2287         pub fn monitor_update_failed(&mut self, order: RAACommitmentOrder, resend_raa: bool, resend_commitment: bool, mut pending_forwards: Vec<(PendingForwardHTLCInfo, u64)>, mut pending_fails: Vec<(HTLCSource, PaymentHash, HTLCFailReason)>) {
2288                 assert_eq!(self.channel_state & ChannelState::MonitorUpdateFailed as u32, 0);
2289                 self.monitor_pending_revoke_and_ack = resend_raa;
2290                 self.monitor_pending_commitment_signed = resend_commitment;
2291                 self.monitor_pending_order = Some(order);
2292                 assert!(self.monitor_pending_forwards.is_empty());
2293                 mem::swap(&mut pending_forwards, &mut self.monitor_pending_forwards);
2294                 assert!(self.monitor_pending_failures.is_empty());
2295                 mem::swap(&mut pending_fails, &mut self.monitor_pending_failures);
2296                 self.channel_state |= ChannelState::MonitorUpdateFailed as u32;
2297         }
2298
2299         /// Indicates that the latest ChannelMonitor update has been committed by the client
2300         /// successfully and we should restore normal operation. Returns messages which should be sent
2301         /// to the remote side.
2302         pub fn monitor_updating_restored(&mut self) -> (Option<msgs::RevokeAndACK>, Option<msgs::CommitmentUpdate>, RAACommitmentOrder, Vec<(PendingForwardHTLCInfo, u64)>, Vec<(HTLCSource, PaymentHash, HTLCFailReason)>) {
2303                 assert_eq!(self.channel_state & ChannelState::MonitorUpdateFailed as u32, ChannelState::MonitorUpdateFailed as u32);
2304                 self.channel_state &= !(ChannelState::MonitorUpdateFailed as u32);
2305
2306                 let mut forwards = Vec::new();
2307                 mem::swap(&mut forwards, &mut self.monitor_pending_forwards);
2308                 let mut failures = Vec::new();
2309                 mem::swap(&mut failures, &mut self.monitor_pending_failures);
2310
2311                 if self.channel_state & (ChannelState::PeerDisconnected as u32) != 0 {
2312                         // Leave monitor_pending_order so we can order our channel_reestablish responses
2313                         self.monitor_pending_revoke_and_ack = false;
2314                         self.monitor_pending_commitment_signed = false;
2315                         return (None, None, RAACommitmentOrder::RevokeAndACKFirst, forwards, failures);
2316                 }
2317
2318                 let raa = if self.monitor_pending_revoke_and_ack {
2319                         Some(self.get_last_revoke_and_ack())
2320                 } else { None };
2321                 let commitment_update = if self.monitor_pending_commitment_signed {
2322                         Some(self.get_last_commitment_update())
2323                 } else { None };
2324
2325                 self.monitor_pending_revoke_and_ack = false;
2326                 self.monitor_pending_commitment_signed = false;
2327                 (raa, commitment_update, self.monitor_pending_order.clone().unwrap(), forwards, failures)
2328         }
2329
2330         pub fn update_fee(&mut self, fee_estimator: &FeeEstimator, msg: &msgs::UpdateFee) -> Result<(), ChannelError> {
2331                 if self.channel_outbound {
2332                         return Err(ChannelError::Close("Non-funding remote tried to update channel fee"));
2333                 }
2334                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2335                         return Err(ChannelError::Close("Peer sent update_fee when we needed a channel_reestablish"));
2336                 }
2337                 Channel::check_remote_fee(fee_estimator, msg.feerate_per_kw)?;
2338                 self.pending_update_fee = Some(msg.feerate_per_kw as u64);
2339                 self.channel_update_count += 1;
2340                 Ok(())
2341         }
2342
2343         fn get_last_revoke_and_ack(&self) -> msgs::RevokeAndACK {
2344                 let next_per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &self.build_local_commitment_secret(self.cur_local_commitment_transaction_number));
2345                 let per_commitment_secret = chan_utils::build_commitment_secret(self.local_keys.commitment_seed, self.cur_local_commitment_transaction_number + 2);
2346                 msgs::RevokeAndACK {
2347                         channel_id: self.channel_id,
2348                         per_commitment_secret,
2349                         next_per_commitment_point,
2350                 }
2351         }
2352
2353         fn get_last_commitment_update(&self) -> msgs::CommitmentUpdate {
2354                 let mut update_add_htlcs = Vec::new();
2355                 let mut update_fulfill_htlcs = Vec::new();
2356                 let mut update_fail_htlcs = Vec::new();
2357                 let mut update_fail_malformed_htlcs = Vec::new();
2358
2359                 for htlc in self.pending_outbound_htlcs.iter() {
2360                         if let &OutboundHTLCState::LocalAnnounced(ref onion_packet) = &htlc.state {
2361                                 update_add_htlcs.push(msgs::UpdateAddHTLC {
2362                                         channel_id: self.channel_id(),
2363                                         htlc_id: htlc.htlc_id,
2364                                         amount_msat: htlc.amount_msat,
2365                                         payment_hash: htlc.payment_hash,
2366                                         cltv_expiry: htlc.cltv_expiry,
2367                                         onion_routing_packet: (**onion_packet).clone(),
2368                                 });
2369                         }
2370                 }
2371
2372                 for htlc in self.pending_inbound_htlcs.iter() {
2373                         if let &InboundHTLCState::LocalRemoved(ref reason) = &htlc.state {
2374                                 match reason {
2375                                         &InboundHTLCRemovalReason::FailRelay(ref err_packet) => {
2376                                                 update_fail_htlcs.push(msgs::UpdateFailHTLC {
2377                                                         channel_id: self.channel_id(),
2378                                                         htlc_id: htlc.htlc_id,
2379                                                         reason: err_packet.clone()
2380                                                 });
2381                                         },
2382                                         &InboundHTLCRemovalReason::FailMalformed((ref sha256_of_onion, ref failure_code)) => {
2383                                                 update_fail_malformed_htlcs.push(msgs::UpdateFailMalformedHTLC {
2384                                                         channel_id: self.channel_id(),
2385                                                         htlc_id: htlc.htlc_id,
2386                                                         sha256_of_onion: sha256_of_onion.clone(),
2387                                                         failure_code: failure_code.clone(),
2388                                                 });
2389                                         },
2390                                         &InboundHTLCRemovalReason::Fulfill(ref payment_preimage) => {
2391                                                 update_fulfill_htlcs.push(msgs::UpdateFulfillHTLC {
2392                                                         channel_id: self.channel_id(),
2393                                                         htlc_id: htlc.htlc_id,
2394                                                         payment_preimage: payment_preimage.clone(),
2395                                                 });
2396                                         },
2397                                 }
2398                         }
2399                 }
2400
2401                 log_trace!(self, "Regenerated latest commitment update with {} update_adds, {} update_fulfills, {} update_fails, and {} update_fail_malformeds",
2402                                 update_add_htlcs.len(), update_fulfill_htlcs.len(), update_fail_htlcs.len(), update_fail_malformed_htlcs.len());
2403                 msgs::CommitmentUpdate {
2404                         update_add_htlcs, update_fulfill_htlcs, update_fail_htlcs, update_fail_malformed_htlcs,
2405                         update_fee: None, //TODO: We need to support re-generating any update_fees in the last commitment_signed!
2406                         commitment_signed: self.send_commitment_no_state_update().expect("It looks like we failed to re-generate a commitment_signed we had previously sent?").0,
2407                 }
2408         }
2409
2410         /// May panic if some calls other than message-handling calls (which will all Err immediately)
2411         /// have been called between remove_uncommitted_htlcs_and_mark_paused and this call.
2412         pub fn channel_reestablish(&mut self, msg: &msgs::ChannelReestablish) -> Result<(Option<msgs::FundingLocked>, Option<msgs::RevokeAndACK>, Option<msgs::CommitmentUpdate>, Option<ChannelMonitor>, RAACommitmentOrder, Option<msgs::Shutdown>), ChannelError> {
2413                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == 0 {
2414                         // While BOLT 2 doesn't indicate explicitly we should error this channel here, it
2415                         // almost certainly indicates we are going to end up out-of-sync in some way, so we
2416                         // just close here instead of trying to recover.
2417                         return Err(ChannelError::Close("Peer sent a loose channel_reestablish not after reconnect"));
2418                 }
2419
2420                 if msg.next_local_commitment_number >= INITIAL_COMMITMENT_NUMBER || msg.next_remote_commitment_number >= INITIAL_COMMITMENT_NUMBER ||
2421                         msg.next_local_commitment_number == 0 {
2422                         return Err(ChannelError::Close("Peer sent a garbage channel_reestablish"));
2423                 }
2424
2425                 // Go ahead and unmark PeerDisconnected as various calls we may make check for it (and all
2426                 // remaining cases either succeed or ErrorMessage-fail).
2427                 self.channel_state &= !(ChannelState::PeerDisconnected as u32);
2428
2429                 let shutdown_msg = if self.channel_state & (ChannelState::LocalShutdownSent as u32) != 0 {
2430                         Some(msgs::Shutdown {
2431                                 channel_id: self.channel_id,
2432                                 scriptpubkey: self.get_closing_scriptpubkey(),
2433                         })
2434                 } else { None };
2435
2436                 if self.channel_state & (ChannelState::FundingSent as u32) == ChannelState::FundingSent as u32 {
2437                         if self.channel_state & ChannelState::OurFundingLocked as u32 == 0 {
2438                                 if msg.next_remote_commitment_number != 0 {
2439                                         return Err(ChannelError::Close("Peer claimed they saw a revoke_and_ack but we haven't sent funding_locked yet"));
2440                                 }
2441                                 // Short circuit the whole handler as there is nothing we can resend them
2442                                 return Ok((None, None, None, None, RAACommitmentOrder::CommitmentFirst, shutdown_msg));
2443                         }
2444
2445                         // We have OurFundingLocked set!
2446                         let next_per_commitment_secret = self.build_local_commitment_secret(self.cur_local_commitment_transaction_number);
2447                         let next_per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &next_per_commitment_secret);
2448                         return Ok((Some(msgs::FundingLocked {
2449                                 channel_id: self.channel_id(),
2450                                 next_per_commitment_point: next_per_commitment_point,
2451                         }), None, None, None, RAACommitmentOrder::CommitmentFirst, shutdown_msg));
2452                 }
2453
2454                 let required_revoke = if msg.next_remote_commitment_number + 1 == INITIAL_COMMITMENT_NUMBER - self.cur_local_commitment_transaction_number {
2455                         // Remote isn't waiting on any RevokeAndACK from us!
2456                         // Note that if we need to repeat our FundingLocked we'll do that in the next if block.
2457                         None
2458                 } else if msg.next_remote_commitment_number + 1 == (INITIAL_COMMITMENT_NUMBER - 1) - self.cur_local_commitment_transaction_number {
2459                         if self.channel_state & (ChannelState::MonitorUpdateFailed as u32) != 0 {
2460                                 self.monitor_pending_revoke_and_ack = true;
2461                                 None
2462                         } else {
2463                                 Some(self.get_last_revoke_and_ack())
2464                         }
2465                 } else {
2466                         return Err(ChannelError::Close("Peer attempted to reestablish channel with a very old local commitment transaction"));
2467                 };
2468
2469                 // We increment cur_remote_commitment_transaction_number only upon receipt of
2470                 // revoke_and_ack, not on sending commitment_signed, so we add one if have
2471                 // AwaitingRemoteRevoke set, which indicates we sent a commitment_signed but haven't gotten
2472                 // the corresponding revoke_and_ack back yet.
2473                 let our_next_remote_commitment_number = INITIAL_COMMITMENT_NUMBER - self.cur_remote_commitment_transaction_number + if (self.channel_state & ChannelState::AwaitingRemoteRevoke as u32) != 0 { 1 } else { 0 };
2474
2475                 let resend_funding_locked = if msg.next_local_commitment_number == 1 && INITIAL_COMMITMENT_NUMBER - self.cur_local_commitment_transaction_number == 1 {
2476                         // We should never have to worry about MonitorUpdateFailed resending FundingLocked
2477                         let next_per_commitment_secret = self.build_local_commitment_secret(self.cur_local_commitment_transaction_number);
2478                         let next_per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &next_per_commitment_secret);
2479                         Some(msgs::FundingLocked {
2480                                 channel_id: self.channel_id(),
2481                                 next_per_commitment_point: next_per_commitment_point,
2482                         })
2483                 } else { None };
2484
2485                 let order = self.monitor_pending_order.clone().unwrap_or(if self.received_commitment_while_awaiting_raa {
2486                                 RAACommitmentOrder::CommitmentFirst
2487                         } else {
2488                                 RAACommitmentOrder::RevokeAndACKFirst
2489                         });
2490
2491                 if msg.next_local_commitment_number == our_next_remote_commitment_number {
2492                         if required_revoke.is_some() {
2493                                 log_debug!(self, "Reconnected channel {} with only lost outbound RAA", log_bytes!(self.channel_id()));
2494                         } else {
2495                                 log_debug!(self, "Reconnected channel {} with no loss", log_bytes!(self.channel_id()));
2496                         }
2497
2498                         if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::MonitorUpdateFailed as u32)) == 0 &&
2499                                         self.monitor_pending_order.is_none() { // monitor_pending_order indicates we're waiting on a response to a unfreeze
2500                                 // We're up-to-date and not waiting on a remote revoke (if we are our
2501                                 // channel_reestablish should result in them sending a revoke_and_ack), but we may
2502                                 // have received some updates while we were disconnected. Free the holding cell
2503                                 // now!
2504                                 match self.free_holding_cell_htlcs() {
2505                                         Err(ChannelError::Close(msg)) => return Err(ChannelError::Close(msg)),
2506                                         Err(ChannelError::Ignore(_)) => panic!("Got non-channel-failing result from free_holding_cell_htlcs"),
2507                                         Ok(Some((commitment_update, channel_monitor))) => return Ok((resend_funding_locked, required_revoke, Some(commitment_update), Some(channel_monitor), order, shutdown_msg)),
2508                                         Ok(None) => return Ok((resend_funding_locked, required_revoke, None, None, order, shutdown_msg)),
2509                                 }
2510                         } else {
2511                                 return Ok((resend_funding_locked, required_revoke, None, None, order, shutdown_msg));
2512                         }
2513                 } else if msg.next_local_commitment_number == our_next_remote_commitment_number - 1 {
2514                         if required_revoke.is_some() {
2515                                 log_debug!(self, "Reconnected channel {} with lost outbound RAA and lost remote commitment tx", log_bytes!(self.channel_id()));
2516                         } else {
2517                                 log_debug!(self, "Reconnected channel {} with only lost remote commitment tx", log_bytes!(self.channel_id()));
2518                         }
2519
2520                         if self.channel_state & (ChannelState::MonitorUpdateFailed as u32) != 0 {
2521                                 self.monitor_pending_commitment_signed = true;
2522                                 return Ok((resend_funding_locked, None, None, None, order, shutdown_msg));
2523                         }
2524
2525                         return Ok((resend_funding_locked, required_revoke, Some(self.get_last_commitment_update()), None, order, shutdown_msg));
2526                 } else {
2527                         return Err(ChannelError::Close("Peer attempted to reestablish channel with a very old remote commitment transaction"));
2528                 }
2529         }
2530
2531         fn maybe_propose_first_closing_signed(&mut self, fee_estimator: &FeeEstimator) -> Option<msgs::ClosingSigned> {
2532                 if !self.channel_outbound || !self.pending_inbound_htlcs.is_empty() || !self.pending_outbound_htlcs.is_empty() ||
2533                                 self.channel_state & (BOTH_SIDES_SHUTDOWN_MASK | ChannelState::AwaitingRemoteRevoke as u32) != BOTH_SIDES_SHUTDOWN_MASK ||
2534                                 self.last_sent_closing_fee.is_some() || self.pending_update_fee.is_some() {
2535                         return None;
2536                 }
2537
2538                 let mut proposed_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background);
2539                 if self.feerate_per_kw > proposed_feerate {
2540                         proposed_feerate = self.feerate_per_kw;
2541                 }
2542                 let tx_weight = Self::get_closing_transaction_weight(&self.get_closing_scriptpubkey(), self.their_shutdown_scriptpubkey.as_ref().unwrap());
2543                 let proposed_total_fee_satoshis = proposed_feerate * tx_weight / 1000;
2544
2545                 let (closing_tx, total_fee_satoshis) = self.build_closing_transaction(proposed_total_fee_satoshis, false);
2546                 let funding_redeemscript = self.get_funding_redeemscript();
2547                 let sighash = hash_to_message!(&bip143::SighashComponents::new(&closing_tx).sighash_all(&closing_tx.input[0], &funding_redeemscript, self.channel_value_satoshis)[..]);
2548
2549                 self.last_sent_closing_fee = Some((proposed_feerate, total_fee_satoshis));
2550                 Some(msgs::ClosingSigned {
2551                         channel_id: self.channel_id,
2552                         fee_satoshis: total_fee_satoshis,
2553                         signature: self.secp_ctx.sign(&sighash, &self.local_keys.funding_key),
2554                 })
2555         }
2556
2557         pub fn shutdown(&mut self, fee_estimator: &FeeEstimator, msg: &msgs::Shutdown) -> Result<(Option<msgs::Shutdown>, Option<msgs::ClosingSigned>, Vec<(HTLCSource, PaymentHash)>), ChannelError> {
2558                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2559                         return Err(ChannelError::Close("Peer sent shutdown when we needed a channel_reestablish"));
2560                 }
2561                 if self.channel_state < ChannelState::FundingSent as u32 {
2562                         // Spec says we should fail the connection, not the channel, but that's nonsense, there
2563                         // are plenty of reasons you may want to fail a channel pre-funding, and spec says you
2564                         // can do that via error message without getting a connection fail anyway...
2565                         return Err(ChannelError::Close("Peer sent shutdown pre-funding generation"));
2566                 }
2567                 for htlc in self.pending_inbound_htlcs.iter() {
2568                         if let InboundHTLCState::RemoteAnnounced(_) = htlc.state {
2569                                 return Err(ChannelError::Close("Got shutdown with remote pending HTLCs"));
2570                         }
2571                 }
2572                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
2573
2574                 // BOLT 2 says we must only send a scriptpubkey of certain standard forms, which are up to
2575                 // 34 bytes in length, so don't let the remote peer feed us some super fee-heavy script.
2576                 if self.channel_outbound && msg.scriptpubkey.len() > 34 {
2577                         return Err(ChannelError::Close("Got shutdown_scriptpubkey of absurd length from remote peer"));
2578                 }
2579
2580                 //Check shutdown_scriptpubkey form as BOLT says we must
2581                 if !msg.scriptpubkey.is_p2pkh() && !msg.scriptpubkey.is_p2sh() && !msg.scriptpubkey.is_v0_p2wpkh() && !msg.scriptpubkey.is_v0_p2wsh() {
2582                         return Err(ChannelError::Close("Got a nonstandard scriptpubkey from remote peer"));
2583                 }
2584
2585                 if self.their_shutdown_scriptpubkey.is_some() {
2586                         if Some(&msg.scriptpubkey) != self.their_shutdown_scriptpubkey.as_ref() {
2587                                 return Err(ChannelError::Close("Got shutdown request with a scriptpubkey which did not match their previous scriptpubkey"));
2588                         }
2589                 } else {
2590                         self.their_shutdown_scriptpubkey = Some(msg.scriptpubkey.clone());
2591                 }
2592
2593                 // From here on out, we may not fail!
2594
2595                 self.channel_state |= ChannelState::RemoteShutdownSent as u32;
2596                 self.channel_update_count += 1;
2597
2598                 // We can't send our shutdown until we've committed all of our pending HTLCs, but the
2599                 // remote side is unlikely to accept any new HTLCs, so we go ahead and "free" any holding
2600                 // cell HTLCs and return them to fail the payment.
2601                 self.holding_cell_update_fee = None;
2602                 let mut dropped_outbound_htlcs = Vec::with_capacity(self.holding_cell_htlc_updates.len());
2603                 self.holding_cell_htlc_updates.retain(|htlc_update| {
2604                         match htlc_update {
2605                                 &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, ref source, .. } => {
2606                                         dropped_outbound_htlcs.push((source.clone(), payment_hash.clone()));
2607                                         false
2608                                 },
2609                                 _ => true
2610                         }
2611                 });
2612                 // If we have any LocalAnnounced updates we'll probably just get back a update_fail_htlc
2613                 // immediately after the commitment dance, but we can send a Shutdown cause we won't send
2614                 // any further commitment updates after we set LocalShutdownSent.
2615
2616                 let our_shutdown = if (self.channel_state & ChannelState::LocalShutdownSent as u32) == ChannelState::LocalShutdownSent as u32 {
2617                         None
2618                 } else {
2619                         Some(msgs::Shutdown {
2620                                 channel_id: self.channel_id,
2621                                 scriptpubkey: self.get_closing_scriptpubkey(),
2622                         })
2623                 };
2624
2625                 self.channel_state |= ChannelState::LocalShutdownSent as u32;
2626                 self.channel_update_count += 1;
2627                 Ok((our_shutdown, self.maybe_propose_first_closing_signed(fee_estimator), dropped_outbound_htlcs))
2628         }
2629
2630         pub fn closing_signed(&mut self, fee_estimator: &FeeEstimator, msg: &msgs::ClosingSigned) -> Result<(Option<msgs::ClosingSigned>, Option<Transaction>), ChannelError> {
2631                 if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK != BOTH_SIDES_SHUTDOWN_MASK {
2632                         return Err(ChannelError::Close("Remote end sent us a closing_signed before both sides provided a shutdown"));
2633                 }
2634                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2635                         return Err(ChannelError::Close("Peer sent closing_signed when we needed a channel_reestablish"));
2636                 }
2637                 if !self.pending_inbound_htlcs.is_empty() || !self.pending_outbound_htlcs.is_empty() {
2638                         return Err(ChannelError::Close("Remote end sent us a closing_signed while there were still pending HTLCs"));
2639                 }
2640                 if msg.fee_satoshis > 21000000 * 10000000 { //this is required to stop potential overflow in build_closing_transaction
2641                         return Err(ChannelError::Close("Remote tried to send us a closing tx with > 21 million BTC fee"));
2642                 }
2643
2644                 let funding_redeemscript = self.get_funding_redeemscript();
2645                 let (mut closing_tx, used_total_fee) = self.build_closing_transaction(msg.fee_satoshis, false);
2646                 if used_total_fee != msg.fee_satoshis {
2647                         return Err(ChannelError::Close("Remote sent us a closing_signed with a fee greater than the value they can claim"));
2648                 }
2649                 let mut sighash = hash_to_message!(&bip143::SighashComponents::new(&closing_tx).sighash_all(&closing_tx.input[0], &funding_redeemscript, self.channel_value_satoshis)[..]);
2650
2651                 match self.secp_ctx.verify(&sighash, &msg.signature, &self.their_funding_pubkey.unwrap()) {
2652                         Ok(_) => {},
2653                         Err(_e) => {
2654                                 // The remote end may have decided to revoke their output due to inconsistent dust
2655                                 // limits, so check for that case by re-checking the signature here.
2656                                 closing_tx = self.build_closing_transaction(msg.fee_satoshis, true).0;
2657                                 sighash = hash_to_message!(&bip143::SighashComponents::new(&closing_tx).sighash_all(&closing_tx.input[0], &funding_redeemscript, self.channel_value_satoshis)[..]);
2658                                 secp_check!(self.secp_ctx.verify(&sighash, &msg.signature, &self.their_funding_pubkey.unwrap()), "Invalid closing tx signature from peer");
2659                         },
2660                 };
2661
2662                 if let Some((_, last_fee)) = self.last_sent_closing_fee {
2663                         if last_fee == msg.fee_satoshis {
2664                                 self.sign_commitment_transaction(&mut closing_tx, &msg.signature);
2665                                 self.channel_state = ChannelState::ShutdownComplete as u32;
2666                                 self.channel_update_count += 1;
2667                                 return Ok((None, Some(closing_tx)));
2668                         }
2669                 }
2670
2671                 macro_rules! propose_new_feerate {
2672                         ($new_feerate: expr) => {
2673                                 let closing_tx_max_weight = Self::get_closing_transaction_weight(&self.get_closing_scriptpubkey(), self.their_shutdown_scriptpubkey.as_ref().unwrap());
2674                                 let (closing_tx, used_total_fee) = self.build_closing_transaction($new_feerate * closing_tx_max_weight / 1000, false);
2675                                 sighash = hash_to_message!(&bip143::SighashComponents::new(&closing_tx).sighash_all(&closing_tx.input[0], &funding_redeemscript, self.channel_value_satoshis)[..]);
2676                                 let our_sig = self.secp_ctx.sign(&sighash, &self.local_keys.funding_key);
2677                                 self.last_sent_closing_fee = Some(($new_feerate, used_total_fee));
2678                                 return Ok((Some(msgs::ClosingSigned {
2679                                         channel_id: self.channel_id,
2680                                         fee_satoshis: used_total_fee,
2681                                         signature: our_sig,
2682                                 }), None))
2683                         }
2684                 }
2685
2686                 let proposed_sat_per_kw = msg.fee_satoshis * 1000 / closing_tx.get_weight();
2687                 if self.channel_outbound {
2688                         let our_max_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Normal);
2689                         if proposed_sat_per_kw > our_max_feerate {
2690                                 if let Some((last_feerate, _)) = self.last_sent_closing_fee {
2691                                         if our_max_feerate <= last_feerate {
2692                                                 return Err(ChannelError::Close("Unable to come to consensus about closing feerate, remote wanted something higher than our Normal feerate"));
2693                                         }
2694                                 }
2695                                 propose_new_feerate!(our_max_feerate);
2696                         }
2697                 } else {
2698                         let our_min_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background);
2699                         if proposed_sat_per_kw < our_min_feerate {
2700                                 if let Some((last_feerate, _)) = self.last_sent_closing_fee {
2701                                         if our_min_feerate >= last_feerate {
2702                                                 return Err(ChannelError::Close("Unable to come to consensus about closing feerate, remote wanted something lower than our Background feerate"));
2703                                         }
2704                                 }
2705                                 propose_new_feerate!(our_min_feerate);
2706                         }
2707                 }
2708
2709                 let our_sig = self.sign_commitment_transaction(&mut closing_tx, &msg.signature);
2710                 self.channel_state = ChannelState::ShutdownComplete as u32;
2711                 self.channel_update_count += 1;
2712
2713                 Ok((Some(msgs::ClosingSigned {
2714                         channel_id: self.channel_id,
2715                         fee_satoshis: msg.fee_satoshis,
2716                         signature: our_sig,
2717                 }), Some(closing_tx)))
2718         }
2719
2720         // Public utilities:
2721
2722         pub fn channel_id(&self) -> [u8; 32] {
2723                 self.channel_id
2724         }
2725
2726         /// Gets the "user_id" value passed into the construction of this channel. It has no special
2727         /// meaning and exists only to allow users to have a persistent identifier of a channel.
2728         pub fn get_user_id(&self) -> u64 {
2729                 self.user_id
2730         }
2731
2732         /// May only be called after funding has been initiated (ie is_funding_initiated() is true)
2733         pub fn channel_monitor(&self) -> ChannelMonitor {
2734                 if self.channel_state < ChannelState::FundingCreated as u32 {
2735                         panic!("Can't get a channel monitor until funding has been created");
2736                 }
2737                 self.channel_monitor.clone()
2738         }
2739
2740         /// Guaranteed to be Some after both FundingLocked messages have been exchanged (and, thus,
2741         /// is_usable() returns true).
2742         /// Allowed in any state (including after shutdown)
2743         pub fn get_short_channel_id(&self) -> Option<u64> {
2744                 self.short_channel_id
2745         }
2746
2747         /// Returns the funding_txo we either got from our peer, or were given by
2748         /// get_outbound_funding_created.
2749         pub fn get_funding_txo(&self) -> Option<OutPoint> {
2750                 self.channel_monitor.get_funding_txo()
2751         }
2752
2753         /// Allowed in any state (including after shutdown)
2754         pub fn get_their_node_id(&self) -> PublicKey {
2755                 self.their_node_id
2756         }
2757
2758         /// Allowed in any state (including after shutdown)
2759         pub fn get_our_htlc_minimum_msat(&self) -> u64 {
2760                 self.our_htlc_minimum_msat
2761         }
2762
2763         /// Allowed in any state (including after shutdown)
2764         pub fn get_their_htlc_minimum_msat(&self) -> u64 {
2765                 self.our_htlc_minimum_msat
2766         }
2767
2768         pub fn get_value_satoshis(&self) -> u64 {
2769                 self.channel_value_satoshis
2770         }
2771
2772         pub fn get_fee_proportional_millionths(&self) -> u32 {
2773                 self.config.fee_proportional_millionths
2774         }
2775
2776         #[cfg(test)]
2777         pub fn get_feerate(&self) -> u64 {
2778                 self.feerate_per_kw
2779         }
2780
2781         pub fn get_cur_local_commitment_transaction_number(&self) -> u64 {
2782                 self.cur_local_commitment_transaction_number + 1
2783         }
2784
2785         pub fn get_cur_remote_commitment_transaction_number(&self) -> u64 {
2786                 self.cur_remote_commitment_transaction_number + 1 - if self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32) != 0 { 1 } else { 0 }
2787         }
2788
2789         pub fn get_revoked_remote_commitment_transaction_number(&self) -> u64 {
2790                 self.cur_remote_commitment_transaction_number + 2
2791         }
2792
2793         //TODO: Testing purpose only, should be changed in another way after #81
2794         #[cfg(test)]
2795         pub fn get_local_keys(&self) -> &ChannelKeys {
2796                 &self.local_keys
2797         }
2798
2799         #[cfg(test)]
2800         pub fn get_value_stat(&self) -> ChannelValueStat {
2801                 ChannelValueStat {
2802                         value_to_self_msat: self.value_to_self_msat,
2803                         channel_value_msat: self.channel_value_satoshis * 1000,
2804                         channel_reserve_msat: self.their_channel_reserve_satoshis * 1000,
2805                         pending_outbound_htlcs_amount_msat: self.pending_outbound_htlcs.iter().map(|ref h| h.amount_msat).sum::<u64>(),
2806                         pending_inbound_htlcs_amount_msat: self.pending_inbound_htlcs.iter().map(|ref h| h.amount_msat).sum::<u64>(),
2807                         holding_cell_outbound_amount_msat: {
2808                                 let mut res = 0;
2809                                 for h in self.holding_cell_htlc_updates.iter() {
2810                                         match h {
2811                                                 &HTLCUpdateAwaitingACK::AddHTLC{amount_msat, .. } => {
2812                                                         res += amount_msat;
2813                                                 }
2814                                                 _ => {}
2815                                         }
2816                                 }
2817                                 res
2818                         },
2819                         their_max_htlc_value_in_flight_msat: self.their_max_htlc_value_in_flight_msat,
2820                 }
2821         }
2822
2823         /// Allowed in any state (including after shutdown)
2824         pub fn get_channel_update_count(&self) -> u32 {
2825                 self.channel_update_count
2826         }
2827
2828         pub fn should_announce(&self) -> bool {
2829                 self.config.announced_channel
2830         }
2831
2832         pub fn is_outbound(&self) -> bool {
2833                 self.channel_outbound
2834         }
2835
2836         /// Gets the fee we'd want to charge for adding an HTLC output to this Channel
2837         /// Allowed in any state (including after shutdown)
2838         pub fn get_our_fee_base_msat(&self, fee_estimator: &FeeEstimator) -> u32 {
2839                 // For lack of a better metric, we calculate what it would cost to consolidate the new HTLC
2840                 // output value back into a transaction with the regular channel output:
2841
2842                 // the fee cost of the HTLC-Success/HTLC-Timeout transaction:
2843                 let mut res = self.feerate_per_kw * cmp::max(HTLC_TIMEOUT_TX_WEIGHT, HTLC_SUCCESS_TX_WEIGHT) / 1000;
2844
2845                 if self.channel_outbound {
2846                         // + the marginal fee increase cost to us in the commitment transaction:
2847                         res += self.feerate_per_kw * COMMITMENT_TX_WEIGHT_PER_HTLC / 1000;
2848                 }
2849
2850                 // + the marginal cost of an input which spends the HTLC-Success/HTLC-Timeout output:
2851                 res += fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Normal) * SPENDING_INPUT_FOR_A_OUTPUT_WEIGHT / 1000;
2852
2853                 res as u32
2854         }
2855
2856         /// Returns true if we've ever received a message from the remote end for this Channel
2857         pub fn have_received_message(&self) -> bool {
2858                 self.channel_state > (ChannelState::OurInitSent as u32)
2859         }
2860
2861         /// Returns true if this channel is fully established and not known to be closing.
2862         /// Allowed in any state (including after shutdown)
2863         pub fn is_usable(&self) -> bool {
2864                 let mask = ChannelState::ChannelFunded as u32 | BOTH_SIDES_SHUTDOWN_MASK;
2865                 (self.channel_state & mask) == (ChannelState::ChannelFunded as u32)
2866         }
2867
2868         /// Returns true if this channel is currently available for use. This is a superset of
2869         /// is_usable() and considers things like the channel being temporarily disabled.
2870         /// Allowed in any state (including after shutdown)
2871         pub fn is_live(&self) -> bool {
2872                 self.is_usable() && (self.channel_state & (ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32) == 0)
2873         }
2874
2875         /// Returns true if this channel has been marked as awaiting a monitor update to move forward.
2876         /// Allowed in any state (including after shutdown)
2877         pub fn is_awaiting_monitor_update(&self) -> bool {
2878                 (self.channel_state & ChannelState::MonitorUpdateFailed as u32) != 0
2879         }
2880
2881         /// Returns true if funding_created was sent/received.
2882         pub fn is_funding_initiated(&self) -> bool {
2883                 self.channel_state >= ChannelState::FundingCreated as u32
2884         }
2885
2886         /// Returns true if this channel is fully shut down. True here implies that no further actions
2887         /// may/will be taken on this channel, and thus this object should be freed. Any future changes
2888         /// will be handled appropriately by the chain monitor.
2889         pub fn is_shutdown(&self) -> bool {
2890                 if (self.channel_state & ChannelState::ShutdownComplete as u32) == ChannelState::ShutdownComplete as u32  {
2891                         assert!(self.channel_state == ChannelState::ShutdownComplete as u32);
2892                         true
2893                 } else { false }
2894         }
2895
2896         /// Called by channelmanager based on chain blocks being connected.
2897         /// Note that we only need to use this to detect funding_signed, anything else is handled by
2898         /// the channel_monitor.
2899         /// In case of Err, the channel may have been closed, at which point the standard requirements
2900         /// apply - no calls may be made except those explicitly stated to be allowed post-shutdown.
2901         /// Only returns an ErrorAction of DisconnectPeer, if Err.
2902         pub fn block_connected(&mut self, header: &BlockHeader, height: u32, txn_matched: &[&Transaction], indexes_of_txn_matched: &[u32]) -> Result<Option<msgs::FundingLocked>, msgs::ErrorMessage> {
2903                 let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
2904                 if header.bitcoin_hash() != self.last_block_connected {
2905                         self.last_block_connected = header.bitcoin_hash();
2906                         self.channel_monitor.last_block_hash = self.last_block_connected;
2907                         if self.funding_tx_confirmations > 0 {
2908                                 self.funding_tx_confirmations += 1;
2909                                 if self.funding_tx_confirmations == self.minimum_depth as u64 {
2910                                         let need_commitment_update = if non_shutdown_state == ChannelState::FundingSent as u32 {
2911                                                 self.channel_state |= ChannelState::OurFundingLocked as u32;
2912                                                 true
2913                                         } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::TheirFundingLocked as u32) {
2914                                                 self.channel_state = ChannelState::ChannelFunded as u32 | (self.channel_state & MULTI_STATE_FLAGS);
2915                                                 self.channel_update_count += 1;
2916                                                 true
2917                                         } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::OurFundingLocked as u32) {
2918                                                 // We got a reorg but not enough to trigger a force close, just update
2919                                                 // funding_tx_confirmed_in and return.
2920                                                 false
2921                                         } else if self.channel_state < ChannelState::ChannelFunded as u32 {
2922                                                 panic!("Started confirming a channel in a state pre-FundingSent?: {}", self.channel_state);
2923                                         } else {
2924                                                 // We got a reorg but not enough to trigger a force close, just update
2925                                                 // funding_tx_confirmed_in and return.
2926                                                 false
2927                                         };
2928                                         self.funding_tx_confirmed_in = Some(header.bitcoin_hash());
2929
2930                                         //TODO: Note that this must be a duplicate of the previous commitment point they sent us,
2931                                         //as otherwise we will have a commitment transaction that they can't revoke (well, kinda,
2932                                         //they can by sending two revoke_and_acks back-to-back, but not really). This appears to be
2933                                         //a protocol oversight, but I assume I'm just missing something.
2934                                         if need_commitment_update {
2935                                                 let next_per_commitment_secret = self.build_local_commitment_secret(self.cur_local_commitment_transaction_number);
2936                                                 let next_per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &next_per_commitment_secret);
2937                                                 return Ok(Some(msgs::FundingLocked {
2938                                                         channel_id: self.channel_id,
2939                                                         next_per_commitment_point: next_per_commitment_point,
2940                                                 }));
2941                                         }
2942                                 }
2943                         }
2944                 }
2945                 if non_shutdown_state & !(ChannelState::TheirFundingLocked as u32) == ChannelState::FundingSent as u32 {
2946                         for (ref tx, index_in_block) in txn_matched.iter().zip(indexes_of_txn_matched) {
2947                                 if tx.txid() == self.channel_monitor.get_funding_txo().unwrap().txid {
2948                                         let txo_idx = self.channel_monitor.get_funding_txo().unwrap().index as usize;
2949                                         if txo_idx >= tx.output.len() || tx.output[txo_idx].script_pubkey != self.get_funding_redeemscript().to_v0_p2wsh() ||
2950                                                         tx.output[txo_idx].value != self.channel_value_satoshis {
2951                                                 if self.channel_outbound {
2952                                                         // If we generated the funding transaction and it doesn't match what it
2953                                                         // should, the client is really broken and we should just panic and
2954                                                         // tell them off. That said, because hash collisions happen with high
2955                                                         // probability in fuzztarget mode, if we're fuzzing we just close the
2956                                                         // channel and move on.
2957                                                         #[cfg(not(feature = "fuzztarget"))]
2958                                                         panic!("Client called ChannelManager::funding_transaction_generated with bogus transaction!");
2959                                                 }
2960                                                 self.channel_state = ChannelState::ShutdownComplete as u32;
2961                                                 self.channel_update_count += 1;
2962                                                 return Err(msgs::ErrorMessage {
2963                                                         channel_id: self.channel_id(),
2964                                                         data: "funding tx had wrong script/value".to_owned()
2965                                                 });
2966                                         } else {
2967                                                 if self.channel_outbound {
2968                                                         for input in tx.input.iter() {
2969                                                                 if input.witness.is_empty() {
2970                                                                         // We generated a malleable funding transaction, implying we've
2971                                                                         // just exposed ourselves to funds loss to our counterparty.
2972                                                                         #[cfg(not(feature = "fuzztarget"))]
2973                                                                         panic!("Client called ChannelManager::funding_transaction_generated with bogus transaction!");
2974                                                                 }
2975                                                         }
2976                                                 }
2977                                                 self.funding_tx_confirmations = 1;
2978                                                 self.short_channel_id = Some(((height as u64)          << (5*8)) |
2979                                                                              ((*index_in_block as u64) << (2*8)) |
2980                                                                              ((txo_idx as u64)         << (0*8)));
2981                                         }
2982                                 }
2983                         }
2984                 }
2985                 Ok(None)
2986         }
2987
2988         /// Called by channelmanager based on chain blocks being disconnected.
2989         /// Returns true if we need to close the channel now due to funding transaction
2990         /// unconfirmation/reorg.
2991         pub fn block_disconnected(&mut self, header: &BlockHeader) -> bool {
2992                 if self.funding_tx_confirmations > 0 {
2993                         self.funding_tx_confirmations -= 1;
2994                         if self.funding_tx_confirmations == UNCONF_THRESHOLD as u64 {
2995                                 return true;
2996                         }
2997                 }
2998                 if Some(header.bitcoin_hash()) == self.funding_tx_confirmed_in {
2999                         self.funding_tx_confirmations = self.minimum_depth as u64 - 1;
3000                 }
3001                 self.last_block_connected = header.bitcoin_hash();
3002                 self.channel_monitor.last_block_hash = self.last_block_connected;
3003                 false
3004         }
3005
3006         // Methods to get unprompted messages to send to the remote end (or where we already returned
3007         // something in the handler for the message that prompted this message):
3008
3009         pub fn get_open_channel(&self, chain_hash: Sha256dHash, fee_estimator: &FeeEstimator) -> msgs::OpenChannel {
3010                 if !self.channel_outbound {
3011                         panic!("Tried to open a channel for an inbound channel?");
3012                 }
3013                 if self.channel_state != ChannelState::OurInitSent as u32 {
3014                         panic!("Cannot generate an open_channel after we've moved forward");
3015                 }
3016
3017                 if self.cur_local_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
3018                         panic!("Tried to send an open_channel for a channel that has already advanced");
3019                 }
3020
3021                 let local_commitment_secret = self.build_local_commitment_secret(self.cur_local_commitment_transaction_number);
3022
3023                 msgs::OpenChannel {
3024                         chain_hash: chain_hash,
3025                         temporary_channel_id: self.channel_id,
3026                         funding_satoshis: self.channel_value_satoshis,
3027                         push_msat: self.channel_value_satoshis * 1000 - self.value_to_self_msat,
3028                         dust_limit_satoshis: self.our_dust_limit_satoshis,
3029                         max_htlc_value_in_flight_msat: Channel::get_our_max_htlc_value_in_flight_msat(self.channel_value_satoshis),
3030                         channel_reserve_satoshis: Channel::get_our_channel_reserve_satoshis(self.channel_value_satoshis),
3031                         htlc_minimum_msat: self.our_htlc_minimum_msat,
3032                         feerate_per_kw: fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background) as u32,
3033                         to_self_delay: BREAKDOWN_TIMEOUT,
3034                         max_accepted_htlcs: OUR_MAX_HTLCS,
3035                         funding_pubkey: PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.funding_key),
3036                         revocation_basepoint: PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.revocation_base_key),
3037                         payment_basepoint: PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.payment_base_key),
3038                         delayed_payment_basepoint: PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.delayed_payment_base_key),
3039                         htlc_basepoint: PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.htlc_base_key),
3040                         first_per_commitment_point: PublicKey::from_secret_key(&self.secp_ctx, &local_commitment_secret),
3041                         channel_flags: if self.config.announced_channel {1} else {0},
3042                         shutdown_scriptpubkey: OptionalField::Absent
3043                 }
3044         }
3045
3046         pub fn get_accept_channel(&self) -> msgs::AcceptChannel {
3047                 if self.channel_outbound {
3048                         panic!("Tried to send accept_channel for an outbound channel?");
3049                 }
3050                 if self.channel_state != (ChannelState::OurInitSent as u32) | (ChannelState::TheirInitSent as u32) {
3051                         panic!("Tried to send accept_channel after channel had moved forward");
3052                 }
3053                 if self.cur_local_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
3054                         panic!("Tried to send an accept_channel for a channel that has already advanced");
3055                 }
3056
3057                 let local_commitment_secret = self.build_local_commitment_secret(self.cur_local_commitment_transaction_number);
3058
3059                 msgs::AcceptChannel {
3060                         temporary_channel_id: self.channel_id,
3061                         dust_limit_satoshis: self.our_dust_limit_satoshis,
3062                         max_htlc_value_in_flight_msat: Channel::get_our_max_htlc_value_in_flight_msat(self.channel_value_satoshis),
3063                         channel_reserve_satoshis: Channel::get_our_channel_reserve_satoshis(self.channel_value_satoshis),
3064                         htlc_minimum_msat: self.our_htlc_minimum_msat,
3065                         minimum_depth: self.minimum_depth,
3066                         to_self_delay: BREAKDOWN_TIMEOUT,
3067                         max_accepted_htlcs: OUR_MAX_HTLCS,
3068                         funding_pubkey: PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.funding_key),
3069                         revocation_basepoint: PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.revocation_base_key),
3070                         payment_basepoint: PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.payment_base_key),
3071                         delayed_payment_basepoint: PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.delayed_payment_base_key),
3072                         htlc_basepoint: PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.htlc_base_key),
3073                         first_per_commitment_point: PublicKey::from_secret_key(&self.secp_ctx, &local_commitment_secret),
3074                         shutdown_scriptpubkey: OptionalField::Absent
3075                 }
3076         }
3077
3078         /// If an Err is returned, it is a ChannelError::Close (for get_outbound_funding_created)
3079         fn get_outbound_funding_created_signature(&mut self) -> Result<(Signature, Transaction), ChannelError> {
3080                 let funding_script = self.get_funding_redeemscript();
3081
3082                 let remote_keys = self.build_remote_transaction_keys()?;
3083                 let remote_initial_commitment_tx = self.build_commitment_transaction(self.cur_remote_commitment_transaction_number, &remote_keys, false, false, self.feerate_per_kw).0;
3084                 let remote_sighash = hash_to_message!(&bip143::SighashComponents::new(&remote_initial_commitment_tx).sighash_all(&remote_initial_commitment_tx.input[0], &funding_script, self.channel_value_satoshis)[..]);
3085
3086                 // We sign the "remote" commitment transaction, allowing them to broadcast the tx if they wish.
3087                 Ok((self.secp_ctx.sign(&remote_sighash, &self.local_keys.funding_key), remote_initial_commitment_tx))
3088         }
3089
3090         /// Updates channel state with knowledge of the funding transaction's txid/index, and generates
3091         /// a funding_created message for the remote peer.
3092         /// Panics if called at some time other than immediately after initial handshake, if called twice,
3093         /// or if called on an inbound channel.
3094         /// Note that channel_id changes during this call!
3095         /// Do NOT broadcast the funding transaction until after a successful funding_signed call!
3096         /// If an Err is returned, it is a ChannelError::Close.
3097         pub fn get_outbound_funding_created(&mut self, funding_txo: OutPoint) -> Result<(msgs::FundingCreated, ChannelMonitor), ChannelError> {
3098                 if !self.channel_outbound {
3099                         panic!("Tried to create outbound funding_created message on an inbound channel!");
3100                 }
3101                 if self.channel_state != (ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32) {
3102                         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)");
3103                 }
3104                 if self.channel_monitor.get_min_seen_secret() != (1 << 48) ||
3105                                 self.cur_remote_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER ||
3106                                 self.cur_local_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
3107                         panic!("Should not have advanced channel commitment tx numbers prior to funding_created");
3108                 }
3109
3110                 let funding_txo_script = self.get_funding_redeemscript().to_v0_p2wsh();
3111                 self.channel_monitor.set_funding_info((funding_txo, funding_txo_script));
3112
3113                 let (our_signature, commitment_tx) = match self.get_outbound_funding_created_signature() {
3114                         Ok(res) => res,
3115                         Err(e) => {
3116                                 log_error!(self, "Got bad signatures: {:?}!", e);
3117                                 self.channel_monitor.unset_funding_info();
3118                                 return Err(e);
3119                         }
3120                 };
3121
3122                 let temporary_channel_id = self.channel_id;
3123
3124                 // Now that we're past error-generating stuff, update our local state:
3125                 self.channel_monitor.provide_latest_remote_commitment_tx_info(&commitment_tx, Vec::new(), self.cur_remote_commitment_transaction_number, self.their_cur_commitment_point.unwrap());
3126                 self.channel_state = ChannelState::FundingCreated as u32;
3127                 self.channel_id = funding_txo.to_channel_id();
3128                 self.cur_remote_commitment_transaction_number -= 1;
3129
3130                 Ok((msgs::FundingCreated {
3131                         temporary_channel_id: temporary_channel_id,
3132                         funding_txid: funding_txo.txid,
3133                         funding_output_index: funding_txo.index,
3134                         signature: our_signature
3135                 }, self.channel_monitor.clone()))
3136         }
3137
3138         /// Gets an UnsignedChannelAnnouncement, as well as a signature covering it using our
3139         /// bitcoin_key, if available, for this channel. The channel must be publicly announceable and
3140         /// available for use (have exchanged FundingLocked messages in both directions). Should be used
3141         /// for both loose and in response to an AnnouncementSignatures message from the remote peer.
3142         /// Will only fail if we're not in a state where channel_announcement may be sent (including
3143         /// closing).
3144         /// Note that the "channel must be funded" requirement is stricter than BOLT 7 requires - see
3145         /// https://github.com/lightningnetwork/lightning-rfc/issues/468
3146         pub fn get_channel_announcement(&self, our_node_id: PublicKey, chain_hash: Sha256dHash) -> Result<(msgs::UnsignedChannelAnnouncement, Signature), ChannelError> {
3147                 if !self.config.announced_channel {
3148                         return Err(ChannelError::Ignore("Channel is not available for public announcements"));
3149                 }
3150                 if self.channel_state & (ChannelState::ChannelFunded as u32) == 0 {
3151                         return Err(ChannelError::Ignore("Cannot get a ChannelAnnouncement until the channel funding has been locked"));
3152                 }
3153                 if (self.channel_state & (ChannelState::LocalShutdownSent as u32 | ChannelState::ShutdownComplete as u32)) != 0 {
3154                         return Err(ChannelError::Ignore("Cannot get a ChannelAnnouncement once the channel is closing"));
3155                 }
3156
3157                 let were_node_one = our_node_id.serialize()[..] < self.their_node_id.serialize()[..];
3158                 let our_bitcoin_key = PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.funding_key);
3159
3160                 let msg = msgs::UnsignedChannelAnnouncement {
3161                         features: msgs::GlobalFeatures::new(),
3162                         chain_hash: chain_hash,
3163                         short_channel_id: self.get_short_channel_id().unwrap(),
3164                         node_id_1: if were_node_one { our_node_id } else { self.get_their_node_id() },
3165                         node_id_2: if were_node_one { self.get_their_node_id() } else { our_node_id },
3166                         bitcoin_key_1: if were_node_one { our_bitcoin_key } else { self.their_funding_pubkey.unwrap() },
3167                         bitcoin_key_2: if were_node_one { self.their_funding_pubkey.unwrap() } else { our_bitcoin_key },
3168                         excess_data: Vec::new(),
3169                 };
3170
3171                 let msghash = hash_to_message!(&Sha256dHash::hash(&msg.encode()[..])[..]);
3172                 let sig = self.secp_ctx.sign(&msghash, &self.local_keys.funding_key);
3173
3174                 Ok((msg, sig))
3175         }
3176
3177         /// May panic if called on a channel that wasn't immediately-previously
3178         /// self.remove_uncommitted_htlcs_and_mark_paused()'d
3179         pub fn get_channel_reestablish(&self) -> msgs::ChannelReestablish {
3180                 assert_eq!(self.channel_state & ChannelState::PeerDisconnected as u32, ChannelState::PeerDisconnected as u32);
3181                 assert_ne!(self.cur_remote_commitment_transaction_number, INITIAL_COMMITMENT_NUMBER);
3182                 msgs::ChannelReestablish {
3183                         channel_id: self.channel_id(),
3184                         // The protocol has two different commitment number concepts - the "commitment
3185                         // transaction number", which starts from 0 and counts up, and the "revocation key
3186                         // index" which starts at INITIAL_COMMITMENT_NUMBER and counts down. We track
3187                         // commitment transaction numbers by the index which will be used to reveal the
3188                         // revocation key for that commitment transaction, which means we have to convert them
3189                         // to protocol-level commitment numbers here...
3190
3191                         // next_local_commitment_number is the next commitment_signed number we expect to
3192                         // receive (indicating if they need to resend one that we missed).
3193                         next_local_commitment_number: INITIAL_COMMITMENT_NUMBER - self.cur_local_commitment_transaction_number,
3194                         // We have to set next_remote_commitment_number to the next revoke_and_ack we expect to
3195                         // receive, however we track it by the next commitment number for a remote transaction
3196                         // (which is one further, as they always revoke previous commitment transaction, not
3197                         // the one we send) so we have to decrement by 1. Note that if
3198                         // cur_remote_commitment_transaction_number is INITIAL_COMMITMENT_NUMBER we will have
3199                         // dropped this channel on disconnect as it hasn't yet reached FundingSent so we can't
3200                         // overflow here.
3201                         next_remote_commitment_number: INITIAL_COMMITMENT_NUMBER - self.cur_remote_commitment_transaction_number - 1,
3202                         data_loss_protect: OptionalField::Absent,
3203                 }
3204         }
3205
3206
3207         // Send stuff to our remote peers:
3208
3209         /// Adds a pending outbound HTLC to this channel, note that you probably want
3210         /// send_htlc_and_commit instead cause you'll want both messages at once.
3211         /// This returns an option instead of a pure UpdateAddHTLC as we may be in a state where we are
3212         /// waiting on the remote peer to send us a revoke_and_ack during which time we cannot add new
3213         /// HTLCs on the wire or we wouldn't be able to determine what they actually ACK'ed.
3214         /// You MUST call send_commitment prior to any other calls on this Channel
3215         /// If an Err is returned, it's a ChannelError::Ignore!
3216         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> {
3217                 if (self.channel_state & (ChannelState::ChannelFunded as u32 | BOTH_SIDES_SHUTDOWN_MASK)) != (ChannelState::ChannelFunded as u32) {
3218                         return Err(ChannelError::Ignore("Cannot send HTLC until channel is fully established and we haven't started shutting down"));
3219                 }
3220
3221                 if amount_msat > self.channel_value_satoshis * 1000 {
3222                         return Err(ChannelError::Ignore("Cannot send more than the total value of the channel"));
3223                 }
3224                 if amount_msat < self.their_htlc_minimum_msat {
3225                         return Err(ChannelError::Ignore("Cannot send less than their minimum HTLC value"));
3226                 }
3227
3228                 if (self.channel_state & (ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32)) != 0 {
3229                         // Note that this should never really happen, if we're !is_live() on receipt of an
3230                         // incoming HTLC for relay will result in us rejecting the HTLC and we won't allow
3231                         // the user to send directly into a !is_live() channel. However, if we
3232                         // disconnected during the time the previous hop was doing the commitment dance we may
3233                         // end up getting here after the forwarding delay. In any case, returning an
3234                         // IgnoreError will get ChannelManager to do the right thing and fail backwards now.
3235                         return Err(ChannelError::Ignore("Cannot send an HTLC while disconnected/frozen for channel monitor update"));
3236                 }
3237
3238                 let (outbound_htlc_count, htlc_outbound_value_msat) = self.get_outbound_pending_htlc_stats();
3239                 if outbound_htlc_count + 1 > self.their_max_accepted_htlcs as u32 {
3240                         return Err(ChannelError::Ignore("Cannot push more than their max accepted HTLCs"));
3241                 }
3242                 //TODO: Spec is unclear if this is per-direction or in total (I assume per direction):
3243                 // Check their_max_htlc_value_in_flight_msat
3244                 if htlc_outbound_value_msat + amount_msat > self.their_max_htlc_value_in_flight_msat {
3245                         return Err(ChannelError::Ignore("Cannot send value that would put us over the max HTLC value in flight"));
3246                 }
3247
3248                 // Check self.their_channel_reserve_satoshis (the amount we must keep as
3249                 // reserve for them to have something to claim if we misbehave)
3250                 if self.value_to_self_msat < self.their_channel_reserve_satoshis * 1000 + amount_msat + htlc_outbound_value_msat {
3251                         return Err(ChannelError::Ignore("Cannot send value that would put us over the reserve value"));
3252                 }
3253
3254                 //TODO: Check cltv_expiry? Do this in channel manager?
3255
3256                 // Now update local state:
3257                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == (ChannelState::AwaitingRemoteRevoke as u32) {
3258                         self.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::AddHTLC {
3259                                 amount_msat: amount_msat,
3260                                 payment_hash: payment_hash,
3261                                 cltv_expiry: cltv_expiry,
3262                                 source,
3263                                 onion_routing_packet: onion_routing_packet,
3264                                 time_created: Instant::now(),
3265                         });
3266                         return Ok(None);
3267                 }
3268
3269                 self.pending_outbound_htlcs.push(OutboundHTLCOutput {
3270                         htlc_id: self.next_local_htlc_id,
3271                         amount_msat: amount_msat,
3272                         payment_hash: payment_hash.clone(),
3273                         cltv_expiry: cltv_expiry,
3274                         state: OutboundHTLCState::LocalAnnounced(Box::new(onion_routing_packet.clone())),
3275                         source,
3276                 });
3277
3278                 let res = msgs::UpdateAddHTLC {
3279                         channel_id: self.channel_id,
3280                         htlc_id: self.next_local_htlc_id,
3281                         amount_msat: amount_msat,
3282                         payment_hash: payment_hash,
3283                         cltv_expiry: cltv_expiry,
3284                         onion_routing_packet: onion_routing_packet,
3285                 };
3286                 self.next_local_htlc_id += 1;
3287
3288                 Ok(Some(res))
3289         }
3290
3291         /// Creates a signed commitment transaction to send to the remote peer.
3292         /// Always returns a ChannelError::Close if an immediately-preceding (read: the
3293         /// last call to this Channel) send_htlc returned Ok(Some(_)) and there is an Err.
3294         /// May panic if called except immediately after a successful, Ok(Some(_))-returning send_htlc.
3295         pub fn send_commitment(&mut self) -> Result<(msgs::CommitmentSigned, ChannelMonitor), ChannelError> {
3296                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
3297                         panic!("Cannot create commitment tx until channel is fully established");
3298                 }
3299                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == (ChannelState::AwaitingRemoteRevoke as u32) {
3300                         panic!("Cannot create commitment tx until remote revokes their previous commitment");
3301                 }
3302                 if (self.channel_state & (ChannelState::PeerDisconnected as u32)) == (ChannelState::PeerDisconnected as u32) {
3303                         panic!("Cannot create commitment tx while disconnected, as send_htlc will have returned an Err so a send_commitment precondition has been violated");
3304                 }
3305                 if (self.channel_state & (ChannelState::MonitorUpdateFailed as u32)) == (ChannelState::MonitorUpdateFailed as u32) {
3306                         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");
3307                 }
3308                 let mut have_updates = self.pending_update_fee.is_some();
3309                 for htlc in self.pending_outbound_htlcs.iter() {
3310                         if let OutboundHTLCState::LocalAnnounced(_) = htlc.state {
3311                                 have_updates = true;
3312                         }
3313                         if have_updates { break; }
3314                 }
3315                 for htlc in self.pending_inbound_htlcs.iter() {
3316                         if let InboundHTLCState::LocalRemoved(_) = htlc.state {
3317                                 have_updates = true;
3318                         }
3319                         if have_updates { break; }
3320                 }
3321                 if !have_updates {
3322                         panic!("Cannot create commitment tx until we have some updates to send");
3323                 }
3324                 self.send_commitment_no_status_check()
3325         }
3326         /// Only fails in case of bad keys
3327         fn send_commitment_no_status_check(&mut self) -> Result<(msgs::CommitmentSigned, ChannelMonitor), ChannelError> {
3328                 // We can upgrade the status of some HTLCs that are waiting on a commitment, even if we
3329                 // fail to generate this, we still are at least at a position where upgrading their status
3330                 // is acceptable.
3331                 for htlc in self.pending_inbound_htlcs.iter_mut() {
3332                         let new_state = if let &InboundHTLCState::AwaitingRemoteRevokeToAnnounce(ref forward_info) = &htlc.state {
3333                                 Some(InboundHTLCState::AwaitingAnnouncedRemoteRevoke(forward_info.clone()))
3334                         } else { None };
3335                         if let Some(state) = new_state {
3336                                 htlc.state = state;
3337                         }
3338                 }
3339                 for htlc in self.pending_outbound_htlcs.iter_mut() {
3340                         if let Some(fail_reason) = if let &mut OutboundHTLCState::AwaitingRemoteRevokeToRemove(ref mut fail_reason) = &mut htlc.state {
3341                                 Some(fail_reason.take())
3342                         } else { None } {
3343                                 htlc.state = OutboundHTLCState::AwaitingRemovedRemoteRevoke(fail_reason);
3344                         }
3345                 }
3346
3347                 let (res, remote_commitment_tx, htlcs) = match self.send_commitment_no_state_update() {
3348                         Ok((res, (remote_commitment_tx, mut htlcs))) => {
3349                                 // Update state now that we've passed all the can-fail calls...
3350                                 let htlcs_no_ref = htlcs.drain(..).map(|(htlc, htlc_source)| (htlc, htlc_source.map(|source_ref| Box::new(source_ref.clone())))).collect();
3351                                 (res, remote_commitment_tx, htlcs_no_ref)
3352                         },
3353                         Err(e) => return Err(e),
3354                 };
3355
3356                 self.channel_monitor.provide_latest_remote_commitment_tx_info(&remote_commitment_tx, htlcs, self.cur_remote_commitment_transaction_number, self.their_cur_commitment_point.unwrap());
3357                 self.channel_state |= ChannelState::AwaitingRemoteRevoke as u32;
3358                 Ok((res, self.channel_monitor.clone()))
3359         }
3360
3361         /// Only fails in case of bad keys. Used for channel_reestablish commitment_signed generation
3362         /// when we shouldn't change HTLC/channel state.
3363         fn send_commitment_no_state_update(&self) -> Result<(msgs::CommitmentSigned, (Transaction, Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)>)), ChannelError> {
3364                 let funding_script = self.get_funding_redeemscript();
3365
3366                 let mut feerate_per_kw = self.feerate_per_kw;
3367                 if let Some(feerate) = self.pending_update_fee {
3368                         if self.channel_outbound {
3369                                 feerate_per_kw = feerate;
3370                         }
3371                 }
3372
3373                 let remote_keys = self.build_remote_transaction_keys()?;
3374                 let remote_commitment_tx = self.build_commitment_transaction(self.cur_remote_commitment_transaction_number, &remote_keys, false, true, feerate_per_kw);
3375                 let remote_commitment_txid = remote_commitment_tx.0.txid();
3376                 let remote_sighash = hash_to_message!(&bip143::SighashComponents::new(&remote_commitment_tx.0).sighash_all(&remote_commitment_tx.0.input[0], &funding_script, self.channel_value_satoshis)[..]);
3377                 let our_sig = self.secp_ctx.sign(&remote_sighash, &self.local_keys.funding_key);
3378                 log_trace!(self, "Signing remote commitment tx {} with redeemscript {} with pubkey {} -> {}", encode::serialize_hex(&remote_commitment_tx.0), encode::serialize_hex(&funding_script), log_bytes!(PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.funding_key).serialize()), log_bytes!(our_sig.serialize_compact()[..]));
3379
3380                 let mut htlc_sigs = Vec::with_capacity(remote_commitment_tx.1);
3381                 for &(ref htlc, _) in remote_commitment_tx.2.iter() {
3382                         if let Some(_) = htlc.transaction_output_index {
3383                                 let htlc_tx = self.build_htlc_transaction(&remote_commitment_txid, htlc, false, &remote_keys, feerate_per_kw);
3384                                 let htlc_redeemscript = chan_utils::get_htlc_redeemscript(&htlc, &remote_keys);
3385                                 let htlc_sighash = hash_to_message!(&bip143::SighashComponents::new(&htlc_tx).sighash_all(&htlc_tx.input[0], &htlc_redeemscript, htlc.amount_msat / 1000)[..]);
3386                                 let our_htlc_key = secp_check!(chan_utils::derive_private_key(&self.secp_ctx, &remote_keys.per_commitment_point, &self.local_keys.htlc_base_key), "Derived invalid key, peer is maliciously selecting parameters");
3387                                 htlc_sigs.push(self.secp_ctx.sign(&htlc_sighash, &our_htlc_key));
3388                                 log_trace!(self, "Signing remote HTLC tx {} with redeemscript {} with pubkey {} -> {}", encode::serialize_hex(&htlc_tx), encode::serialize_hex(&htlc_redeemscript), log_bytes!(PublicKey::from_secret_key(&self.secp_ctx, &our_htlc_key).serialize()), log_bytes!(htlc_sigs.last().unwrap().serialize_compact()[..]));
3389                         }
3390                 }
3391
3392                 Ok((msgs::CommitmentSigned {
3393                         channel_id: self.channel_id,
3394                         signature: our_sig,
3395                         htlc_signatures: htlc_sigs,
3396                 }, (remote_commitment_tx.0, remote_commitment_tx.2)))
3397         }
3398
3399         /// Adds a pending outbound HTLC to this channel, and creates a signed commitment transaction
3400         /// to send to the remote peer in one go.
3401         /// Shorthand for calling send_htlc() followed by send_commitment(), see docs on those for
3402         /// more info.
3403         pub fn send_htlc_and_commit(&mut self, amount_msat: u64, payment_hash: PaymentHash, cltv_expiry: u32, source: HTLCSource, onion_routing_packet: msgs::OnionPacket) -> Result<Option<(msgs::UpdateAddHTLC, msgs::CommitmentSigned, ChannelMonitor)>, ChannelError> {
3404                 match self.send_htlc(amount_msat, payment_hash, cltv_expiry, source, onion_routing_packet)? {
3405                         Some(update_add_htlc) => {
3406                                 let (commitment_signed, monitor_update) = self.send_commitment_no_status_check()?;
3407                                 Ok(Some((update_add_htlc, commitment_signed, monitor_update)))
3408                         },
3409                         None => Ok(None)
3410                 }
3411         }
3412
3413         /// Begins the shutdown process, getting a message for the remote peer and returning all
3414         /// holding cell HTLCs for payment failure.
3415         pub fn get_shutdown(&mut self) -> Result<(msgs::Shutdown, Vec<(HTLCSource, PaymentHash)>), APIError> {
3416                 for htlc in self.pending_outbound_htlcs.iter() {
3417                         if let OutboundHTLCState::LocalAnnounced(_) = htlc.state {
3418                                 return Err(APIError::APIMisuseError{err: "Cannot begin shutdown with pending HTLCs. Process pending events first"});
3419                         }
3420                 }
3421                 if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK != 0 {
3422                         if (self.channel_state & ChannelState::LocalShutdownSent as u32) == ChannelState::LocalShutdownSent as u32 {
3423                                 return Err(APIError::APIMisuseError{err: "Shutdown already in progress"});
3424                         }
3425                         else if (self.channel_state & ChannelState::RemoteShutdownSent as u32) == ChannelState::RemoteShutdownSent as u32 {
3426                                 return Err(APIError::ChannelUnavailable{err: "Shutdown already in progress by remote"});
3427                         }
3428                 }
3429                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
3430                 if self.channel_state & (ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32) != 0 {
3431                         return Err(APIError::ChannelUnavailable{err: "Cannot begin shutdown while peer is disconnected or we're waiting on a monitor update, maybe force-close instead?"});
3432                 }
3433
3434                 let our_closing_script = self.get_closing_scriptpubkey();
3435
3436                 // From here on out, we may not fail!
3437                 if self.channel_state < ChannelState::FundingSent as u32 {
3438                         self.channel_state = ChannelState::ShutdownComplete as u32;
3439                 } else {
3440                         self.channel_state |= ChannelState::LocalShutdownSent as u32;
3441                 }
3442                 self.channel_update_count += 1;
3443
3444                 // Go ahead and drop holding cell updates as we'd rather fail payments than wait to send
3445                 // our shutdown until we've committed all of the pending changes.
3446                 self.holding_cell_update_fee = None;
3447                 let mut dropped_outbound_htlcs = Vec::with_capacity(self.holding_cell_htlc_updates.len());
3448                 self.holding_cell_htlc_updates.retain(|htlc_update| {
3449                         match htlc_update {
3450                                 &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, ref source, .. } => {
3451                                         dropped_outbound_htlcs.push((source.clone(), payment_hash.clone()));
3452                                         false
3453                                 },
3454                                 _ => true
3455                         }
3456                 });
3457
3458                 Ok((msgs::Shutdown {
3459                         channel_id: self.channel_id,
3460                         scriptpubkey: our_closing_script,
3461                 }, dropped_outbound_htlcs))
3462         }
3463
3464         /// Gets the latest commitment transaction and any dependent transactions for relay (forcing
3465         /// shutdown of this channel - no more calls into this Channel may be made afterwards except
3466         /// those explicitly stated to be allowed after shutdown completes, eg some simple getters).
3467         /// Also returns the list of payment_hashes for channels which we can safely fail backwards
3468         /// immediately (others we will have to allow to time out).
3469         pub fn force_shutdown(&mut self) -> (Vec<Transaction>, Vec<(HTLCSource, PaymentHash)>) {
3470                 assert!(self.channel_state != ChannelState::ShutdownComplete as u32);
3471
3472                 // We go ahead and "free" any holding cell HTLCs or HTLCs we haven't yet committed to and
3473                 // return them to fail the payment.
3474                 let mut dropped_outbound_htlcs = Vec::with_capacity(self.holding_cell_htlc_updates.len());
3475                 for htlc_update in self.holding_cell_htlc_updates.drain(..) {
3476                         match htlc_update {
3477                                 HTLCUpdateAwaitingACK::AddHTLC { source, payment_hash, .. } => {
3478                                         dropped_outbound_htlcs.push((source, payment_hash));
3479                                 },
3480                                 _ => {}
3481                         }
3482                 }
3483
3484                 for _htlc in self.pending_outbound_htlcs.drain(..) {
3485                         //TODO: Do something with the remaining HTLCs
3486                         //(we need to have the ChannelManager monitor them so we can claim the inbound HTLCs
3487                         //which correspond)
3488                 }
3489
3490                 self.channel_state = ChannelState::ShutdownComplete as u32;
3491                 self.channel_update_count += 1;
3492                 let mut res = Vec::new();
3493                 mem::swap(&mut res, &mut self.last_local_commitment_txn);
3494                 (res, dropped_outbound_htlcs)
3495         }
3496 }
3497
3498 const SERIALIZATION_VERSION: u8 = 1;
3499 const MIN_SERIALIZATION_VERSION: u8 = 1;
3500
3501 impl Writeable for InboundHTLCRemovalReason {
3502         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3503                 match self {
3504                         &InboundHTLCRemovalReason::FailRelay(ref error_packet) => {
3505                                 0u8.write(writer)?;
3506                                 error_packet.write(writer)?;
3507                         },
3508                         &InboundHTLCRemovalReason::FailMalformed((ref onion_hash, ref err_code)) => {
3509                                 1u8.write(writer)?;
3510                                 onion_hash.write(writer)?;
3511                                 err_code.write(writer)?;
3512                         },
3513                         &InboundHTLCRemovalReason::Fulfill(ref payment_preimage) => {
3514                                 2u8.write(writer)?;
3515                                 payment_preimage.write(writer)?;
3516                         },
3517                 }
3518                 Ok(())
3519         }
3520 }
3521
3522 impl<R: ::std::io::Read> Readable<R> for InboundHTLCRemovalReason {
3523         fn read(reader: &mut R) -> Result<Self, DecodeError> {
3524                 Ok(match <u8 as Readable<R>>::read(reader)? {
3525                         0 => InboundHTLCRemovalReason::FailRelay(Readable::read(reader)?),
3526                         1 => InboundHTLCRemovalReason::FailMalformed((Readable::read(reader)?, Readable::read(reader)?)),
3527                         2 => InboundHTLCRemovalReason::Fulfill(Readable::read(reader)?),
3528                         _ => return Err(DecodeError::InvalidValue),
3529                 })
3530         }
3531 }
3532
3533 impl Writeable for Channel {
3534         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3535                 // Note that we write out as if remove_uncommitted_htlcs_and_mark_paused had just been
3536                 // called but include holding cell updates (and obviously we don't modify self).
3537
3538                 writer.write_all(&[SERIALIZATION_VERSION; 1])?;
3539                 writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
3540
3541                 self.user_id.write(writer)?;
3542                 self.config.write(writer)?;
3543
3544                 self.channel_id.write(writer)?;
3545                 (self.channel_state | ChannelState::PeerDisconnected as u32).write(writer)?;
3546                 self.channel_outbound.write(writer)?;
3547                 self.channel_value_satoshis.write(writer)?;
3548
3549                 self.local_keys.write(writer)?;
3550                 self.shutdown_pubkey.write(writer)?;
3551
3552                 self.cur_local_commitment_transaction_number.write(writer)?;
3553                 self.cur_remote_commitment_transaction_number.write(writer)?;
3554                 self.value_to_self_msat.write(writer)?;
3555
3556                 self.received_commitment_while_awaiting_raa.write(writer)?;
3557
3558                 let mut dropped_inbound_htlcs = 0;
3559                 for htlc in self.pending_inbound_htlcs.iter() {
3560                         if let InboundHTLCState::RemoteAnnounced(_) = htlc.state {
3561                                 dropped_inbound_htlcs += 1;
3562                         }
3563                 }
3564                 (self.pending_inbound_htlcs.len() as u64 - dropped_inbound_htlcs).write(writer)?;
3565                 for htlc in self.pending_inbound_htlcs.iter() {
3566                         htlc.htlc_id.write(writer)?;
3567                         htlc.amount_msat.write(writer)?;
3568                         htlc.cltv_expiry.write(writer)?;
3569                         htlc.payment_hash.write(writer)?;
3570                         match &htlc.state {
3571                                 &InboundHTLCState::RemoteAnnounced(_) => {}, // Drop
3572                                 &InboundHTLCState::AwaitingRemoteRevokeToAnnounce(ref htlc_state) => {
3573                                         1u8.write(writer)?;
3574                                         htlc_state.write(writer)?;
3575                                 },
3576                                 &InboundHTLCState::AwaitingAnnouncedRemoteRevoke(ref htlc_state) => {
3577                                         2u8.write(writer)?;
3578                                         htlc_state.write(writer)?;
3579                                 },
3580                                 &InboundHTLCState::Committed => {
3581                                         3u8.write(writer)?;
3582                                 },
3583                                 &InboundHTLCState::LocalRemoved(ref removal_reason) => {
3584                                         4u8.write(writer)?;
3585                                         removal_reason.write(writer)?;
3586                                 },
3587                         }
3588                 }
3589
3590                 macro_rules! write_option {
3591                         ($thing: expr) => {
3592                                 match &$thing {
3593                                         &None => 0u8.write(writer)?,
3594                                         &Some(ref v) => {
3595                                                 1u8.write(writer)?;
3596                                                 v.write(writer)?;
3597                                         },
3598                                 }
3599                         }
3600                 }
3601
3602                 (self.pending_outbound_htlcs.len() as u64).write(writer)?;
3603                 for htlc in self.pending_outbound_htlcs.iter() {
3604                         htlc.htlc_id.write(writer)?;
3605                         htlc.amount_msat.write(writer)?;
3606                         htlc.cltv_expiry.write(writer)?;
3607                         htlc.payment_hash.write(writer)?;
3608                         htlc.source.write(writer)?;
3609                         match &htlc.state {
3610                                 &OutboundHTLCState::LocalAnnounced(ref onion_packet) => {
3611                                         0u8.write(writer)?;
3612                                         onion_packet.write(writer)?;
3613                                 },
3614                                 &OutboundHTLCState::Committed => {
3615                                         1u8.write(writer)?;
3616                                 },
3617                                 &OutboundHTLCState::RemoteRemoved(ref fail_reason) => {
3618                                         2u8.write(writer)?;
3619                                         write_option!(*fail_reason);
3620                                 },
3621                                 &OutboundHTLCState::AwaitingRemoteRevokeToRemove(ref fail_reason) => {
3622                                         3u8.write(writer)?;
3623                                         write_option!(*fail_reason);
3624                                 },
3625                                 &OutboundHTLCState::AwaitingRemovedRemoteRevoke(ref fail_reason) => {
3626                                         4u8.write(writer)?;
3627                                         write_option!(*fail_reason);
3628                                 },
3629                         }
3630                 }
3631
3632                 (self.holding_cell_htlc_updates.len() as u64).write(writer)?;
3633                 for update in self.holding_cell_htlc_updates.iter() {
3634                         match update {
3635                                 &HTLCUpdateAwaitingACK::AddHTLC { ref amount_msat, ref cltv_expiry, ref payment_hash, ref source, ref onion_routing_packet, time_created: _ } => {
3636                                         0u8.write(writer)?;
3637                                         amount_msat.write(writer)?;
3638                                         cltv_expiry.write(writer)?;
3639                                         payment_hash.write(writer)?;
3640                                         source.write(writer)?;
3641                                         onion_routing_packet.write(writer)?;
3642                                         // time_created is not serialized - we re-init the timeout upon deserialization
3643                                 },
3644                                 &HTLCUpdateAwaitingACK::ClaimHTLC { ref payment_preimage, ref htlc_id } => {
3645                                         1u8.write(writer)?;
3646                                         payment_preimage.write(writer)?;
3647                                         htlc_id.write(writer)?;
3648                                 },
3649                                 &HTLCUpdateAwaitingACK::FailHTLC { ref htlc_id, ref err_packet } => {
3650                                         2u8.write(writer)?;
3651                                         htlc_id.write(writer)?;
3652                                         err_packet.write(writer)?;
3653                                 }
3654                         }
3655                 }
3656
3657                 self.monitor_pending_revoke_and_ack.write(writer)?;
3658                 self.monitor_pending_commitment_signed.write(writer)?;
3659                 match self.monitor_pending_order {
3660                         None => 0u8.write(writer)?,
3661                         Some(RAACommitmentOrder::CommitmentFirst) => 1u8.write(writer)?,
3662                         Some(RAACommitmentOrder::RevokeAndACKFirst) => 2u8.write(writer)?,
3663                 }
3664
3665                 (self.monitor_pending_forwards.len() as u64).write(writer)?;
3666                 for &(ref pending_forward, ref htlc_id) in self.monitor_pending_forwards.iter() {
3667                         pending_forward.write(writer)?;
3668                         htlc_id.write(writer)?;
3669                 }
3670
3671                 (self.monitor_pending_failures.len() as u64).write(writer)?;
3672                 for &(ref htlc_source, ref payment_hash, ref fail_reason) in self.monitor_pending_failures.iter() {
3673                         htlc_source.write(writer)?;
3674                         payment_hash.write(writer)?;
3675                         fail_reason.write(writer)?;
3676                 }
3677
3678                 write_option!(self.pending_update_fee);
3679                 write_option!(self.holding_cell_update_fee);
3680
3681                 self.next_local_htlc_id.write(writer)?;
3682                 (self.next_remote_htlc_id - dropped_inbound_htlcs).write(writer)?;
3683                 self.channel_update_count.write(writer)?;
3684                 self.feerate_per_kw.write(writer)?;
3685
3686                 (self.last_local_commitment_txn.len() as u64).write(writer)?;
3687                 for tx in self.last_local_commitment_txn.iter() {
3688                         if let Err(e) = tx.consensus_encode(&mut WriterWriteAdaptor(writer)) {
3689                                 match e {
3690                                         encode::Error::Io(e) => return Err(e),
3691                                         _ => panic!("last_local_commitment_txn must have been well-formed!"),
3692                                 }
3693                         }
3694                 }
3695
3696                 match self.last_sent_closing_fee {
3697                         Some((feerate, fee)) => {
3698                                 1u8.write(writer)?;
3699                                 feerate.write(writer)?;
3700                                 fee.write(writer)?;
3701                         },
3702                         None => 0u8.write(writer)?,
3703                 }
3704
3705                 write_option!(self.funding_tx_confirmed_in);
3706                 write_option!(self.short_channel_id);
3707
3708                 self.last_block_connected.write(writer)?;
3709                 self.funding_tx_confirmations.write(writer)?;
3710
3711                 self.their_dust_limit_satoshis.write(writer)?;
3712                 self.our_dust_limit_satoshis.write(writer)?;
3713                 self.their_max_htlc_value_in_flight_msat.write(writer)?;
3714                 self.their_channel_reserve_satoshis.write(writer)?;
3715                 self.their_htlc_minimum_msat.write(writer)?;
3716                 self.our_htlc_minimum_msat.write(writer)?;
3717                 self.their_to_self_delay.write(writer)?;
3718                 self.their_max_accepted_htlcs.write(writer)?;
3719                 self.minimum_depth.write(writer)?;
3720
3721                 write_option!(self.their_funding_pubkey);
3722                 write_option!(self.their_revocation_basepoint);
3723                 write_option!(self.their_payment_basepoint);
3724                 write_option!(self.their_delayed_payment_basepoint);
3725                 write_option!(self.their_htlc_basepoint);
3726                 write_option!(self.their_cur_commitment_point);
3727
3728                 write_option!(self.their_prev_commitment_point);
3729                 self.their_node_id.write(writer)?;
3730
3731                 write_option!(self.their_shutdown_scriptpubkey);
3732
3733                 self.channel_monitor.write_for_disk(writer)?;
3734                 Ok(())
3735         }
3736 }
3737
3738 impl<R : ::std::io::Read> ReadableArgs<R, Arc<Logger>> for Channel {
3739         fn read(reader: &mut R, logger: Arc<Logger>) -> Result<Self, DecodeError> {
3740                 let _ver: u8 = Readable::read(reader)?;
3741                 let min_ver: u8 = Readable::read(reader)?;
3742                 if min_ver > SERIALIZATION_VERSION {
3743                         return Err(DecodeError::UnknownVersion);
3744                 }
3745
3746                 let user_id = Readable::read(reader)?;
3747                 let config: ChannelConfig = Readable::read(reader)?;
3748
3749                 let channel_id = Readable::read(reader)?;
3750                 let channel_state = Readable::read(reader)?;
3751                 let channel_outbound = Readable::read(reader)?;
3752                 let channel_value_satoshis = Readable::read(reader)?;
3753
3754                 let local_keys = Readable::read(reader)?;
3755                 let shutdown_pubkey = Readable::read(reader)?;
3756
3757                 let cur_local_commitment_transaction_number = Readable::read(reader)?;
3758                 let cur_remote_commitment_transaction_number = Readable::read(reader)?;
3759                 let value_to_self_msat = Readable::read(reader)?;
3760
3761                 let received_commitment_while_awaiting_raa = Readable::read(reader)?;
3762
3763                 let pending_inbound_htlc_count: u64 = Readable::read(reader)?;
3764                 let mut pending_inbound_htlcs = Vec::with_capacity(cmp::min(pending_inbound_htlc_count as usize, OUR_MAX_HTLCS as usize));
3765                 for _ in 0..pending_inbound_htlc_count {
3766                         pending_inbound_htlcs.push(InboundHTLCOutput {
3767                                 htlc_id: Readable::read(reader)?,
3768                                 amount_msat: Readable::read(reader)?,
3769                                 cltv_expiry: Readable::read(reader)?,
3770                                 payment_hash: Readable::read(reader)?,
3771                                 state: match <u8 as Readable<R>>::read(reader)? {
3772                                         1 => InboundHTLCState::AwaitingRemoteRevokeToAnnounce(Readable::read(reader)?),
3773                                         2 => InboundHTLCState::AwaitingAnnouncedRemoteRevoke(Readable::read(reader)?),
3774                                         3 => InboundHTLCState::Committed,
3775                                         4 => InboundHTLCState::LocalRemoved(Readable::read(reader)?),
3776                                         _ => return Err(DecodeError::InvalidValue),
3777                                 },
3778                         });
3779                 }
3780
3781                 let pending_outbound_htlc_count: u64 = Readable::read(reader)?;
3782                 let mut pending_outbound_htlcs = Vec::with_capacity(cmp::min(pending_outbound_htlc_count as usize, OUR_MAX_HTLCS as usize));
3783                 for _ in 0..pending_outbound_htlc_count {
3784                         pending_outbound_htlcs.push(OutboundHTLCOutput {
3785                                 htlc_id: Readable::read(reader)?,
3786                                 amount_msat: Readable::read(reader)?,
3787                                 cltv_expiry: Readable::read(reader)?,
3788                                 payment_hash: Readable::read(reader)?,
3789                                 source: Readable::read(reader)?,
3790                                 state: match <u8 as Readable<R>>::read(reader)? {
3791                                         0 => OutboundHTLCState::LocalAnnounced(Box::new(Readable::read(reader)?)),
3792                                         1 => OutboundHTLCState::Committed,
3793                                         2 => OutboundHTLCState::RemoteRemoved(Readable::read(reader)?),
3794                                         3 => OutboundHTLCState::AwaitingRemoteRevokeToRemove(Readable::read(reader)?),
3795                                         4 => OutboundHTLCState::AwaitingRemovedRemoteRevoke(Readable::read(reader)?),
3796                                         _ => return Err(DecodeError::InvalidValue),
3797                                 },
3798                         });
3799                 }
3800
3801                 let holding_cell_htlc_update_count: u64 = Readable::read(reader)?;
3802                 let mut holding_cell_htlc_updates = Vec::with_capacity(cmp::min(holding_cell_htlc_update_count as usize, OUR_MAX_HTLCS as usize*2));
3803                 for _ in 0..holding_cell_htlc_update_count {
3804                         holding_cell_htlc_updates.push(match <u8 as Readable<R>>::read(reader)? {
3805                                 0 => HTLCUpdateAwaitingACK::AddHTLC {
3806                                         amount_msat: Readable::read(reader)?,
3807                                         cltv_expiry: Readable::read(reader)?,
3808                                         payment_hash: Readable::read(reader)?,
3809                                         source: Readable::read(reader)?,
3810                                         onion_routing_packet: Readable::read(reader)?,
3811                                         time_created: Instant::now(),
3812                                 },
3813                                 1 => HTLCUpdateAwaitingACK::ClaimHTLC {
3814                                         payment_preimage: Readable::read(reader)?,
3815                                         htlc_id: Readable::read(reader)?,
3816                                 },
3817                                 2 => HTLCUpdateAwaitingACK::FailHTLC {
3818                                         htlc_id: Readable::read(reader)?,
3819                                         err_packet: Readable::read(reader)?,
3820                                 },
3821                                 _ => return Err(DecodeError::InvalidValue),
3822                         });
3823                 }
3824
3825                 let monitor_pending_revoke_and_ack = Readable::read(reader)?;
3826                 let monitor_pending_commitment_signed = Readable::read(reader)?;
3827
3828                 let monitor_pending_order = match <u8 as Readable<R>>::read(reader)? {
3829                         0 => None,
3830                         1 => Some(RAACommitmentOrder::CommitmentFirst),
3831                         2 => Some(RAACommitmentOrder::RevokeAndACKFirst),
3832                         _ => return Err(DecodeError::InvalidValue),
3833                 };
3834
3835                 let monitor_pending_forwards_count: u64 = Readable::read(reader)?;
3836                 let mut monitor_pending_forwards = Vec::with_capacity(cmp::min(monitor_pending_forwards_count as usize, OUR_MAX_HTLCS as usize));
3837                 for _ in 0..monitor_pending_forwards_count {
3838                         monitor_pending_forwards.push((Readable::read(reader)?, Readable::read(reader)?));
3839                 }
3840
3841                 let monitor_pending_failures_count: u64 = Readable::read(reader)?;
3842                 let mut monitor_pending_failures = Vec::with_capacity(cmp::min(monitor_pending_failures_count as usize, OUR_MAX_HTLCS as usize));
3843                 for _ in 0..monitor_pending_failures_count {
3844                         monitor_pending_failures.push((Readable::read(reader)?, Readable::read(reader)?, Readable::read(reader)?));
3845                 }
3846
3847                 let pending_update_fee = Readable::read(reader)?;
3848                 let holding_cell_update_fee = Readable::read(reader)?;
3849
3850                 let next_local_htlc_id = Readable::read(reader)?;
3851                 let next_remote_htlc_id = Readable::read(reader)?;
3852                 let channel_update_count = Readable::read(reader)?;
3853                 let feerate_per_kw = Readable::read(reader)?;
3854
3855                 let last_local_commitment_txn_count: u64 = Readable::read(reader)?;
3856                 let mut last_local_commitment_txn = Vec::with_capacity(cmp::min(last_local_commitment_txn_count as usize, OUR_MAX_HTLCS as usize*2 + 1));
3857                 for _ in 0..last_local_commitment_txn_count {
3858                         last_local_commitment_txn.push(match Transaction::consensus_decode(reader.by_ref()) {
3859                                 Ok(tx) => tx,
3860                                 Err(_) => return Err(DecodeError::InvalidValue),
3861                         });
3862                 }
3863
3864                 let last_sent_closing_fee = match <u8 as Readable<R>>::read(reader)? {
3865                         0 => None,
3866                         1 => Some((Readable::read(reader)?, Readable::read(reader)?)),
3867                         _ => return Err(DecodeError::InvalidValue),
3868                 };
3869
3870                 let funding_tx_confirmed_in = Readable::read(reader)?;
3871                 let short_channel_id = Readable::read(reader)?;
3872
3873                 let last_block_connected = Readable::read(reader)?;
3874                 let funding_tx_confirmations = Readable::read(reader)?;
3875
3876                 let their_dust_limit_satoshis = Readable::read(reader)?;
3877                 let our_dust_limit_satoshis = Readable::read(reader)?;
3878                 let their_max_htlc_value_in_flight_msat = Readable::read(reader)?;
3879                 let their_channel_reserve_satoshis = Readable::read(reader)?;
3880                 let their_htlc_minimum_msat = Readable::read(reader)?;
3881                 let our_htlc_minimum_msat = Readable::read(reader)?;
3882                 let their_to_self_delay = Readable::read(reader)?;
3883                 let their_max_accepted_htlcs = Readable::read(reader)?;
3884                 let minimum_depth = Readable::read(reader)?;
3885
3886                 let their_funding_pubkey = Readable::read(reader)?;
3887                 let their_revocation_basepoint = Readable::read(reader)?;
3888                 let their_payment_basepoint = Readable::read(reader)?;
3889                 let their_delayed_payment_basepoint = Readable::read(reader)?;
3890                 let their_htlc_basepoint = Readable::read(reader)?;
3891                 let their_cur_commitment_point = Readable::read(reader)?;
3892
3893                 let their_prev_commitment_point = Readable::read(reader)?;
3894                 let their_node_id = Readable::read(reader)?;
3895
3896                 let their_shutdown_scriptpubkey = Readable::read(reader)?;
3897                 let (monitor_last_block, channel_monitor) = ReadableArgs::read(reader, logger.clone())?;
3898                 // We drop the ChannelMonitor's last block connected hash cause we don't actually bother
3899                 // doing full block connection operations on the internal CHannelMonitor copies
3900                 if monitor_last_block != last_block_connected {
3901                         return Err(DecodeError::InvalidValue);
3902                 }
3903
3904                 Ok(Channel {
3905                         user_id,
3906
3907                         config,
3908                         channel_id,
3909                         channel_state,
3910                         channel_outbound,
3911                         secp_ctx: Secp256k1::new(),
3912                         channel_value_satoshis,
3913
3914                         local_keys,
3915                         shutdown_pubkey,
3916
3917                         cur_local_commitment_transaction_number,
3918                         cur_remote_commitment_transaction_number,
3919                         value_to_self_msat,
3920
3921                         received_commitment_while_awaiting_raa,
3922                         pending_inbound_htlcs,
3923                         pending_outbound_htlcs,
3924                         holding_cell_htlc_updates,
3925
3926                         monitor_pending_revoke_and_ack,
3927                         monitor_pending_commitment_signed,
3928                         monitor_pending_order,
3929                         monitor_pending_forwards,
3930                         monitor_pending_failures,
3931
3932                         pending_update_fee,
3933                         holding_cell_update_fee,
3934                         next_local_htlc_id,
3935                         next_remote_htlc_id,
3936                         channel_update_count,
3937                         feerate_per_kw,
3938
3939                         #[cfg(debug_assertions)]
3940                         max_commitment_tx_output_local: ::std::sync::Mutex::new((0, 0)),
3941                         #[cfg(debug_assertions)]
3942                         max_commitment_tx_output_remote: ::std::sync::Mutex::new((0, 0)),
3943
3944                         last_local_commitment_txn,
3945
3946                         last_sent_closing_fee,
3947
3948                         funding_tx_confirmed_in,
3949                         short_channel_id,
3950                         last_block_connected,
3951                         funding_tx_confirmations,
3952
3953                         their_dust_limit_satoshis,
3954                         our_dust_limit_satoshis,
3955                         their_max_htlc_value_in_flight_msat,
3956                         their_channel_reserve_satoshis,
3957                         their_htlc_minimum_msat,
3958                         our_htlc_minimum_msat,
3959                         their_to_self_delay,
3960                         their_max_accepted_htlcs,
3961                         minimum_depth,
3962
3963                         their_funding_pubkey,
3964                         their_revocation_basepoint,
3965                         their_payment_basepoint,
3966                         their_delayed_payment_basepoint,
3967                         their_htlc_basepoint,
3968                         their_cur_commitment_point,
3969
3970                         their_prev_commitment_point,
3971                         their_node_id,
3972
3973                         their_shutdown_scriptpubkey,
3974
3975                         channel_monitor,
3976
3977                         logger,
3978                 })
3979         }
3980 }
3981
3982 #[cfg(test)]
3983 mod tests {
3984         use bitcoin::util::bip143;
3985         use bitcoin::consensus::encode::serialize;
3986         use bitcoin::blockdata::script::{Script, Builder};
3987         use bitcoin::blockdata::transaction::Transaction;
3988         use bitcoin::blockdata::opcodes;
3989         use bitcoin_hashes::hex::FromHex;
3990         use hex;
3991         use ln::channelmanager::{HTLCSource, PaymentPreimage, PaymentHash};
3992         use ln::channel::{Channel,ChannelKeys,InboundHTLCOutput,OutboundHTLCOutput,InboundHTLCState,OutboundHTLCState,HTLCOutputInCommitment,TxCreationKeys};
3993         use ln::channel::MAX_FUNDING_SATOSHIS;
3994         use ln::chan_utils;
3995         use chain::chaininterface::{FeeEstimator,ConfirmationTarget};
3996         use chain::keysinterface::KeysInterface;
3997         use chain::transaction::OutPoint;
3998         use util::config::UserConfig;
3999         use util::test_utils;
4000         use util::logger::Logger;
4001         use secp256k1::{Secp256k1,Message,Signature};
4002         use secp256k1::key::{SecretKey,PublicKey};
4003         use bitcoin_hashes::sha256::Hash as Sha256;
4004         use bitcoin_hashes::sha256d::Hash as Sha256dHash;
4005         use bitcoin_hashes::hash160::Hash as Hash160;
4006         use bitcoin_hashes::Hash;
4007         use std::sync::Arc;
4008
4009         struct TestFeeEstimator {
4010                 fee_est: u64
4011         }
4012         impl FeeEstimator for TestFeeEstimator {
4013                 fn get_est_sat_per_1000_weight(&self, _: ConfirmationTarget) -> u64 {
4014                         self.fee_est
4015                 }
4016         }
4017
4018         #[test]
4019         fn test_max_funding_satoshis() {
4020                 assert!(MAX_FUNDING_SATOSHIS <= 21_000_000 * 100_000_000,
4021                         "MAX_FUNDING_SATOSHIS is greater than all satoshis in existence");
4022         }
4023
4024         struct Keys {
4025                 chan_keys: ChannelKeys,
4026         }
4027         impl KeysInterface for Keys {
4028                 fn get_node_secret(&self) -> SecretKey { panic!(); }
4029                 fn get_destination_script(&self) -> Script {
4030                         let secp_ctx = Secp256k1::signing_only();
4031                         let channel_monitor_claim_key = SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap();
4032                         let our_channel_monitor_claim_key_hash = Hash160::hash(&PublicKey::from_secret_key(&secp_ctx, &channel_monitor_claim_key).serialize());
4033                         Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&our_channel_monitor_claim_key_hash[..]).into_script()
4034                 }
4035
4036                 fn get_shutdown_pubkey(&self) -> PublicKey {
4037                         let secp_ctx = Secp256k1::signing_only();
4038                         let channel_close_key = SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap();
4039                         PublicKey::from_secret_key(&secp_ctx, &channel_close_key)
4040                 }
4041
4042                 fn get_channel_keys(&self, _inbound: bool) -> ChannelKeys { self.chan_keys.clone() }
4043                 fn get_session_key(&self) -> SecretKey { panic!(); }
4044                 fn get_channel_id(&self) -> [u8; 32] { [0; 32] }
4045         }
4046
4047         #[test]
4048         fn outbound_commitment_test() {
4049                 // Test vectors from BOLT 3 Appendix C:
4050                 let feeest = TestFeeEstimator{fee_est: 15000};
4051                 let logger : Arc<Logger> = Arc::new(test_utils::TestLogger::new());
4052                 let secp_ctx = Secp256k1::new();
4053
4054                 let chan_keys = ChannelKeys {
4055                         funding_key: SecretKey::from_slice(&hex::decode("30ff4956bbdd3222d44cc5e8a1261dab1e07957bdac5ae88fe3261ef321f3749").unwrap()[..]).unwrap(),
4056                         payment_base_key: SecretKey::from_slice(&hex::decode("1111111111111111111111111111111111111111111111111111111111111111").unwrap()[..]).unwrap(),
4057                         delayed_payment_base_key: SecretKey::from_slice(&hex::decode("3333333333333333333333333333333333333333333333333333333333333333").unwrap()[..]).unwrap(),
4058                         htlc_base_key: SecretKey::from_slice(&hex::decode("1111111111111111111111111111111111111111111111111111111111111111").unwrap()[..]).unwrap(),
4059
4060                         // These aren't set in the test vectors:
4061                         revocation_base_key: SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap(),
4062                         commitment_seed: [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],
4063                 };
4064                 assert_eq!(PublicKey::from_secret_key(&secp_ctx, &chan_keys.funding_key).serialize()[..],
4065                                 hex::decode("023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb").unwrap()[..]);
4066                 let keys_provider: Arc<KeysInterface> = Arc::new(Keys { chan_keys });
4067
4068                 let their_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
4069                 let mut config = UserConfig::new();
4070                 config.channel_options.announced_channel = false;
4071                 let mut chan = Channel::new_outbound(&feeest, &keys_provider, their_node_id, 10000000, 100000, 42, Arc::clone(&logger), &config).unwrap(); // Nothing uses their network key in this test
4072                 chan.their_to_self_delay = 144;
4073                 chan.our_dust_limit_satoshis = 546;
4074
4075                 let funding_info = OutPoint::new(Sha256dHash::from_hex("8984484a580b825b9972d7adb15050b3ab624ccd731946b3eeddb92f4e7ef6be").unwrap(), 0);
4076                 chan.channel_monitor.set_funding_info((funding_info, Script::new()));
4077
4078                 chan.their_payment_basepoint = Some(PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("4444444444444444444444444444444444444444444444444444444444444444").unwrap()[..]).unwrap()));
4079                 assert_eq!(chan.their_payment_basepoint.unwrap().serialize()[..],
4080                                 hex::decode("032c0b7cf95324a07d05398b240174dc0c2be444d96b159aa6c7f7b1e668680991").unwrap()[..]);
4081
4082                 chan.their_funding_pubkey = Some(PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("1552dfba4f6cf29a62a0af13c8d6981d36d0ef8d61ba10fb0fe90da7634d7e13").unwrap()[..]).unwrap()));
4083                 assert_eq!(chan.their_funding_pubkey.unwrap().serialize()[..],
4084                                 hex::decode("030e9f7b623d2ccc7c9bd44d66d5ce21ce504c0acf6385a132cec6d3c39fa711c1").unwrap()[..]);
4085
4086                 chan.their_htlc_basepoint = Some(PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("4444444444444444444444444444444444444444444444444444444444444444").unwrap()[..]).unwrap()));
4087                 assert_eq!(chan.their_htlc_basepoint.unwrap().serialize()[..],
4088                                 hex::decode("032c0b7cf95324a07d05398b240174dc0c2be444d96b159aa6c7f7b1e668680991").unwrap()[..]);
4089
4090                 chan.their_revocation_basepoint = Some(PublicKey::from_slice(&hex::decode("02466d7fcae563e5cb09a0d1870bb580344804617879a14949cf22285f1bae3f27").unwrap()[..]).unwrap());
4091
4092                 // We can't just use build_local_transaction_keys here as the per_commitment_secret is not
4093                 // derived from a commitment_seed, so instead we copy it here and call
4094                 // build_commitment_transaction.
4095                 let delayed_payment_base = PublicKey::from_secret_key(&secp_ctx, &chan.local_keys.delayed_payment_base_key);
4096                 let per_commitment_secret = SecretKey::from_slice(&hex::decode("1f1e1d1c1b1a191817161514131211100f0e0d0c0b0a09080706050403020100").unwrap()[..]).unwrap();
4097                 let per_commitment_point = PublicKey::from_secret_key(&secp_ctx, &per_commitment_secret);
4098                 let htlc_basepoint = PublicKey::from_secret_key(&secp_ctx, &chan.local_keys.htlc_base_key);
4099                 let keys = TxCreationKeys::new(&secp_ctx, &per_commitment_point, &delayed_payment_base, &htlc_basepoint, &chan.their_revocation_basepoint.unwrap(), &chan.their_payment_basepoint.unwrap(), &chan.their_htlc_basepoint.unwrap()).unwrap();
4100
4101                 let mut unsigned_tx: (Transaction, Vec<HTLCOutputInCommitment>);
4102
4103                 macro_rules! test_commitment {
4104                         ( $their_sig_hex: expr, $our_sig_hex: expr, $tx_hex: expr) => {
4105                                 unsigned_tx = {
4106                                         let mut res = chan.build_commitment_transaction(0xffffffffffff - 42, &keys, true, false, chan.feerate_per_kw);
4107                                         let htlcs = res.2.drain(..)
4108                                                 .filter_map(|(htlc, _)| if htlc.transaction_output_index.is_some() { Some(htlc) } else { None })
4109                                                 .collect();
4110                                         (res.0, htlcs)
4111                                 };
4112                                 let their_signature = Signature::from_der(&hex::decode($their_sig_hex).unwrap()[..]).unwrap();
4113                                 let sighash = Message::from_slice(&bip143::SighashComponents::new(&unsigned_tx.0).sighash_all(&unsigned_tx.0.input[0], &chan.get_funding_redeemscript(), chan.channel_value_satoshis)[..]).unwrap();
4114                                 secp_ctx.verify(&sighash, &their_signature, &chan.their_funding_pubkey.unwrap()).unwrap();
4115
4116                                 chan.sign_commitment_transaction(&mut unsigned_tx.0, &their_signature);
4117
4118                                 assert_eq!(serialize(&unsigned_tx.0)[..],
4119                                                 hex::decode($tx_hex).unwrap()[..]);
4120                         };
4121                 }
4122
4123                 macro_rules! test_htlc_output {
4124                         ( $htlc_idx: expr, $their_sig_hex: expr, $our_sig_hex: expr, $tx_hex: expr ) => {
4125                                 let remote_signature = Signature::from_der(&hex::decode($their_sig_hex).unwrap()[..]).unwrap();
4126
4127                                 let ref htlc = unsigned_tx.1[$htlc_idx];
4128                                 let mut htlc_tx = chan.build_htlc_transaction(&unsigned_tx.0.txid(), &htlc, true, &keys, chan.feerate_per_kw);
4129                                 let htlc_redeemscript = chan_utils::get_htlc_redeemscript(&htlc, &keys);
4130                                 let htlc_sighash = Message::from_slice(&bip143::SighashComponents::new(&htlc_tx).sighash_all(&htlc_tx.input[0], &htlc_redeemscript, htlc.amount_msat / 1000)[..]).unwrap();
4131                                 secp_ctx.verify(&htlc_sighash, &remote_signature, &keys.b_htlc_key).unwrap();
4132
4133                                 let mut preimage: Option<PaymentPreimage> = None;
4134                                 if !htlc.offered {
4135                                         for i in 0..5 {
4136                                                 let out = PaymentHash(Sha256::hash(&[i; 32]).into_inner());
4137                                                 if out == htlc.payment_hash {
4138                                                         preimage = Some(PaymentPreimage([i; 32]));
4139                                                 }
4140                                         }
4141
4142                                         assert!(preimage.is_some());
4143                                 }
4144
4145                                 chan.sign_htlc_transaction(&mut htlc_tx, &remote_signature, &preimage, &htlc, &keys).unwrap();
4146                                 assert_eq!(serialize(&htlc_tx)[..],
4147                                                 hex::decode($tx_hex).unwrap()[..]);
4148                         };
4149                 }
4150
4151                 {
4152                         // simple commitment tx with no HTLCs
4153                         chan.value_to_self_msat = 7000000000;
4154
4155                         test_commitment!("3045022100f51d2e566a70ba740fc5d8c0f07b9b93d2ed741c3c0860c613173de7d39e7968022041376d520e9c0e1ad52248ddf4b22e12be8763007df977253ef45a4ca3bdb7c0",
4156                                          "3044022051b75c73198c6deee1a875871c3961832909acd297c6b908d59e3319e5185a46022055c419379c5051a78d00dbbce11b5b664a0c22815fbcc6fcef6b1937c3836939",
4157                                          "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");
4158                 }
4159
4160                 chan.pending_inbound_htlcs.push({
4161                         let mut out = InboundHTLCOutput{
4162                                 htlc_id: 0,
4163                                 amount_msat: 1000000,
4164                                 cltv_expiry: 500,
4165                                 payment_hash: PaymentHash([0; 32]),
4166                                 state: InboundHTLCState::Committed,
4167                         };
4168                         out.payment_hash.0 = Sha256::hash(&hex::decode("0000000000000000000000000000000000000000000000000000000000000000").unwrap()).into_inner();
4169                         out
4170                 });
4171                 chan.pending_inbound_htlcs.push({
4172                         let mut out = InboundHTLCOutput{
4173                                 htlc_id: 1,
4174                                 amount_msat: 2000000,
4175                                 cltv_expiry: 501,
4176                                 payment_hash: PaymentHash([0; 32]),
4177                                 state: InboundHTLCState::Committed,
4178                         };
4179                         out.payment_hash.0 = Sha256::hash(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()).into_inner();
4180                         out
4181                 });
4182                 chan.pending_outbound_htlcs.push({
4183                         let mut out = OutboundHTLCOutput{
4184                                 htlc_id: 2,
4185                                 amount_msat: 2000000,
4186                                 cltv_expiry: 502,
4187                                 payment_hash: PaymentHash([0; 32]),
4188                                 state: OutboundHTLCState::Committed,
4189                                 source: HTLCSource::dummy(),
4190                         };
4191                         out.payment_hash.0 = Sha256::hash(&hex::decode("0202020202020202020202020202020202020202020202020202020202020202").unwrap()).into_inner();
4192                         out
4193                 });
4194                 chan.pending_outbound_htlcs.push({
4195                         let mut out = OutboundHTLCOutput{
4196                                 htlc_id: 3,
4197                                 amount_msat: 3000000,
4198                                 cltv_expiry: 503,
4199                                 payment_hash: PaymentHash([0; 32]),
4200                                 state: OutboundHTLCState::Committed,
4201                                 source: HTLCSource::dummy(),
4202                         };
4203                         out.payment_hash.0 = Sha256::hash(&hex::decode("0303030303030303030303030303030303030303030303030303030303030303").unwrap()).into_inner();
4204                         out
4205                 });
4206                 chan.pending_inbound_htlcs.push({
4207                         let mut out = InboundHTLCOutput{
4208                                 htlc_id: 4,
4209                                 amount_msat: 4000000,
4210                                 cltv_expiry: 504,
4211                                 payment_hash: PaymentHash([0; 32]),
4212                                 state: InboundHTLCState::Committed,
4213                         };
4214                         out.payment_hash.0 = Sha256::hash(&hex::decode("0404040404040404040404040404040404040404040404040404040404040404").unwrap()).into_inner();
4215                         out
4216                 });
4217
4218                 {
4219                         // commitment tx with all five HTLCs untrimmed (minimum feerate)
4220                         chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
4221                         chan.feerate_per_kw = 0;
4222
4223                         test_commitment!("304402204fd4928835db1ccdfc40f5c78ce9bd65249b16348df81f0c44328dcdefc97d630220194d3869c38bc732dd87d13d2958015e2fc16829e74cd4377f84d215c0b70606",
4224                                          "30440220275b0c325a5e9355650dc30c0eccfbc7efb23987c24b556b9dfdd40effca18d202206caceb2c067836c51f296740c7ae807ffcbfbf1dd3a0d56b6de9a5b247985f06",
4225                                          "02000000000101bef67e4e2fb9ddeeb3461973cd4c62abb35050b1add772995b820b584a488489000000000038b02b8007e80300000000000022002052bfef0479d7b293c27e0f1eb294bea154c63a3294ef092c19af51409bce0e2ad007000000000000220020403d394747cae42e98ff01734ad5c08f82ba123d3d9a620abda88989651e2ab5d007000000000000220020748eba944fedc8827f6b06bc44678f93c0f9e6078b35c6331ed31e75f8ce0c2db80b000000000000220020c20b5d1f8584fd90443e7b7b720136174fa4b9333c261d04dbbd012635c0f419a00f0000000000002200208c48d15160397c9731df9bc3b236656efb6665fbfe92b4a6878e88a499f741c4c0c62d0000000000160014ccf1af2f2aabee14bb40fa3851ab2301de843110e0a06a00000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e04004730440220275b0c325a5e9355650dc30c0eccfbc7efb23987c24b556b9dfdd40effca18d202206caceb2c067836c51f296740c7ae807ffcbfbf1dd3a0d56b6de9a5b247985f060147304402204fd4928835db1ccdfc40f5c78ce9bd65249b16348df81f0c44328dcdefc97d630220194d3869c38bc732dd87d13d2958015e2fc16829e74cd4377f84d215c0b7060601475221023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb21030e9f7b623d2ccc7c9bd44d66d5ce21ce504c0acf6385a132cec6d3c39fa711c152ae3e195220");
4226
4227                         assert_eq!(unsigned_tx.1.len(), 5);
4228
4229                         test_htlc_output!(0,
4230                                           "304402206a6e59f18764a5bf8d4fa45eebc591566689441229c918b480fb2af8cc6a4aeb02205248f273be447684b33e3c8d1d85a8e0ca9fa0bae9ae33f0527ada9c162919a6",
4231                                           "304402207cb324fa0de88f452ffa9389678127ebcf4cabe1dd848b8e076c1a1962bf34720220116ed922b12311bd602d67e60d2529917f21c5b82f25ff6506c0f87886b4dfd5",
4232                                           "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");
4233
4234                         test_htlc_output!(1,
4235                                           "3045022100d5275b3619953cb0c3b5aa577f04bc512380e60fa551762ce3d7a1bb7401cff9022037237ab0dac3fe100cde094e82e2bed9ba0ed1bb40154b48e56aa70f259e608b",
4236                                           "3045022100c89172099507ff50f4c925e6c5150e871fb6e83dd73ff9fbb72f6ce829a9633f02203a63821d9162e99f9be712a68f9e589483994feae2661e4546cd5b6cec007be5",
4237                                           "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");
4238
4239                         test_htlc_output!(2,
4240                                           "304402201b63ec807771baf4fdff523c644080de17f1da478989308ad13a58b51db91d360220568939d38c9ce295adba15665fa68f51d967e8ed14a007b751540a80b325f202",
4241                                           "3045022100def389deab09cee69eaa1ec14d9428770e45bcbe9feb46468ecf481371165c2f022015d2e3c46600b2ebba8dcc899768874cc6851fd1ecb3fffd15db1cc3de7e10da",
4242                                           "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");
4243
4244                         test_htlc_output!(3,
4245                                           "3045022100daee1808f9861b6c3ecd14f7b707eca02dd6bdfc714ba2f33bc8cdba507bb182022026654bf8863af77d74f51f4e0b62d461a019561bb12acb120d3f7195d148a554",
4246                                           "30440220643aacb19bbb72bd2b635bc3f7375481f5981bace78cdd8319b2988ffcc6704202203d27784ec8ad51ed3bd517a05525a5139bb0b755dd719e0054332d186ac08727",
4247                                           "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");
4248
4249                         test_htlc_output!(4,
4250                                           "304402207e0410e45454b0978a623f36a10626ef17b27d9ad44e2760f98cfa3efb37924f0220220bd8acd43ecaa916a80bd4f919c495a2c58982ce7c8625153f8596692a801d",
4251                                           "30440220549e80b4496803cbc4a1d09d46df50109f546d43fbbf86cd90b174b1484acd5402205f12a4f995cb9bded597eabfee195a285986aa6d93ae5bb72507ebc6a4e2349e",
4252                                           "020000000001018154ecccf11a5fb56c39654c4deb4d2296f83c69268280b94d021370c94e219704000000000000000001a00f0000000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e050047304402207e0410e45454b0978a623f36a10626ef17b27d9ad44e2760f98cfa3efb37924f0220220bd8acd43ecaa916a80bd4f919c495a2c58982ce7c8625153f8596692a801d014730440220549e80b4496803cbc4a1d09d46df50109f546d43fbbf86cd90b174b1484acd5402205f12a4f995cb9bded597eabfee195a285986aa6d93ae5bb72507ebc6a4e2349e012004040404040404040404040404040404040404040404040404040404040404048a76a91414011f7254d96b819c76986c277d115efce6f7b58763ac67210394854aa6eab5b2a8122cc726e9dded053a2184d88256816826d6231c068d4a5b7c8201208763a91418bc1a114ccf9c052d3d23e28d3b0a9d1227434288527c21030d417a46946384f88d5f3337267c5e579765875dc4daca813e21734b140639e752ae677502f801b175ac686800000000");
4253                 }
4254
4255                 {
4256                         // commitment tx with seven outputs untrimmed (maximum feerate)
4257                         chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
4258                         chan.feerate_per_kw = 647;
4259
4260                         test_commitment!("3045022100a5c01383d3ec646d97e40f44318d49def817fcd61a0ef18008a665b3e151785502203e648efddd5838981ef55ec954be69c4a652d021e6081a100d034de366815e9b",
4261                                          "304502210094bfd8f5572ac0157ec76a9551b6c5216a4538c07cd13a51af4a54cb26fa14320220768efce8ce6f4a5efac875142ff19237c011343670adf9c7ac69704a120d1163",
4262                                          "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");
4263
4264                         assert_eq!(unsigned_tx.1.len(), 5);
4265
4266                         test_htlc_output!(0,
4267                                           "30440220385a5afe75632f50128cbb029ee95c80156b5b4744beddc729ad339c9ca432c802202ba5f48550cad3379ac75b9b4fedb86a35baa6947f16ba5037fb8b11ab343740",
4268                                           "304402205999590b8a79fa346e003a68fd40366397119b2b0cdf37b149968d6bc6fbcc4702202b1e1fb5ab7864931caed4e732c359e0fe3d86a548b557be2246efb1708d579a",
4269                                           "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");
4270
4271                         test_htlc_output!(1,
4272                                           "304402207ceb6678d4db33d2401fdc409959e57c16a6cb97a30261d9c61f29b8c58d34b90220084b4a17b4ca0e86f2d798b3698ca52de5621f2ce86f80bed79afa66874511b0",
4273                                           "304402207ff03eb0127fc7c6cae49cc29e2a586b98d1e8969cf4a17dfa50b9c2647720b902205e2ecfda2252956c0ca32f175080e75e4e390e433feb1f8ce9f2ba55648a1dac",
4274                                           "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");
4275
4276                         test_htlc_output!(2,
4277                                           "304402206a401b29a0dff0d18ec903502c13d83e7ec019450113f4a7655a4ce40d1f65ba0220217723a084e727b6ca0cc8b6c69c014a7e4a01fcdcba3e3993f462a3c574d833",
4278                                           "3045022100d50d067ca625d54e62df533a8f9291736678d0b86c28a61bb2a80cf42e702d6e02202373dde7e00218eacdafb9415fe0e1071beec1857d1af3c6a201a44cbc47c877",
4279                                           "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");
4280
4281                         test_htlc_output!(3,
4282                                           "30450221009b1c987ba599ee3bde1dbca776b85481d70a78b681a8d84206723e2795c7cac002207aac84ad910f8598c4d1c0ea2e3399cf6627a4e3e90131315bc9f038451ce39d",
4283                                           "3045022100db9dc65291077a52728c622987e9895b7241d4394d6dcb916d7600a3e8728c22022036ee3ee717ba0bb5c45ee84bc7bbf85c0f90f26ae4e4a25a6b4241afa8a3f1cb",
4284                                           "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");
4285
4286                         test_htlc_output!(4,
4287                                           "3045022100cc28030b59f0914f45b84caa983b6f8effa900c952310708c2b5b00781117022022027ba2ccdf94d03c6d48b327f183f6e28c8a214d089b9227f94ac4f85315274f0",
4288                                           "304402202d1a3c0d31200265d2a2def2753ead4959ae20b4083e19553acfffa5dfab60bf022020ede134149504e15b88ab261a066de49848411e15e70f9e6a5462aec2949f8f",
4289                                           "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");
4290                 }
4291
4292                 {
4293                         // commitment tx with six outputs untrimmed (minimum feerate)
4294                         chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
4295                         chan.feerate_per_kw = 648;
4296
4297                         test_commitment!("3044022072714e2fbb93cdd1c42eb0828b4f2eff143f717d8f26e79d6ada4f0dcb681bbe02200911be4e5161dd6ebe59ff1c58e1997c4aea804f81db6b698821db6093d7b057",
4298                                          "3045022100a2270d5950c89ae0841233f6efea9c951898b301b2e89e0adbd2c687b9f32efa02207943d90f95b9610458e7c65a576e149750ff3accaacad004cd85e70b235e27de",
4299                                          "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");
4300
4301                         assert_eq!(unsigned_tx.1.len(), 4);
4302
4303                         test_htlc_output!(0,
4304                                           "3044022062ef2e77591409d60d7817d9bb1e71d3c4a2931d1a6c7c8307422c84f001a251022022dad9726b0ae3fe92bda745a06f2c00f92342a186d84518588cf65f4dfaada8",
4305                                           "3045022100a4c574f00411dd2f978ca5cdc1b848c311cd7849c087ad2f21a5bce5e8cc5ae90220090ae39a9bce2fb8bc879d7e9f9022df249f41e25e51f1a9bf6447a9eeffc098",
4306                                           "02000000000101579c183eca9e8236a5d7f5dcd79cfec32c497fdc0ec61533cde99ecd436cadd10000000000000000000123060000000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e0500473044022062ef2e77591409d60d7817d9bb1e71d3c4a2931d1a6c7c8307422c84f001a251022022dad9726b0ae3fe92bda745a06f2c00f92342a186d84518588cf65f4dfaada801483045022100a4c574f00411dd2f978ca5cdc1b848c311cd7849c087ad2f21a5bce5e8cc5ae90220090ae39a9bce2fb8bc879d7e9f9022df249f41e25e51f1a9bf6447a9eeffc09801008576a91414011f7254d96b819c76986c277d115efce6f7b58763ac67210394854aa6eab5b2a8122cc726e9dded053a2184d88256816826d6231c068d4a5b7c820120876475527c21030d417a46946384f88d5f3337267c5e579765875dc4daca813e21734b140639e752ae67a914b43e1b38138a41b37f7cd9a1d274bc63e3a9b5d188ac6868f6010000");
4307
4308                         test_htlc_output!(1,
4309                                           "3045022100e968cbbb5f402ed389fdc7f6cd2a80ed650bb42c79aeb2a5678444af94f6c78502204b47a1cb24ab5b0b6fe69fe9cfc7dba07b9dd0d8b95f372c1d9435146a88f8d4",
4310                                           "304402207679cf19790bea76a733d2fa0672bd43ab455687a068f815a3d237581f57139a0220683a1a799e102071c206b207735ca80f627ab83d6616b4bcd017c5d79ef3e7d0",
4311                                           "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");
4312
4313                         test_htlc_output!(2,
4314                                           "3045022100aa91932e305292cf9969cc23502bbf6cef83a5df39c95ad04a707c4f4fed5c7702207099fc0f3a9bfe1e7683c0e9aa5e76c5432eb20693bf4cb182f04d383dc9c8c2",
4315                                           "304402200df76fea718745f3c529bac7fd37923e7309ce38b25c0781e4cf514dd9ef8dc802204172295739dbae9fe0474dcee3608e3433b4b2af3a2e6787108b02f894dcdda3",
4316                                           "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");
4317
4318                         test_htlc_output!(3,
4319                                           "3044022035cac88040a5bba420b1c4257235d5015309113460bc33f2853cd81ca36e632402202fc94fd3e81e9d34a9d01782a0284f3044370d03d60f3fc041e2da088d2de58f",
4320                                           "304402200daf2eb7afd355b4caf6fb08387b5f031940ea29d1a9f35071288a839c9039e4022067201b562456e7948616c13acb876b386b511599b58ac1d94d127f91c50463a6",
4321                                           "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");
4322                 }
4323
4324                 {
4325                         // commitment tx with six outputs untrimmed (maximum feerate)
4326                         chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
4327                         chan.feerate_per_kw = 2069;
4328
4329                         test_commitment!("3044022001d55e488b8b035b2dd29d50b65b530923a416d47f377284145bc8767b1b6a75022019bb53ddfe1cefaf156f924777eaaf8fdca1810695a7d0a247ad2afba8232eb4",
4330                                          "304402203ca8f31c6a47519f83255dc69f1894d9a6d7476a19f498d31eaf0cd3a85eeb63022026fd92dc752b33905c4c838c528b692a8ad4ced959990b5d5ee2ff940fa90eea",
4331                                          "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");
4332
4333                         assert_eq!(unsigned_tx.1.len(), 4);
4334
4335                         test_htlc_output!(0,
4336                                           "3045022100d1cf354de41c1369336cf85b225ed033f1f8982a01be503668df756a7e668b66022001254144fb4d0eecc61908fccc3388891ba17c5d7a1a8c62bdd307e5a513f992",
4337                                           "3044022056eb1af429660e45a1b0b66568cb8c4a3aa7e4c9c292d5d6c47f86ebf2c8838f022065c3ac4ebe980ca7a41148569be4ad8751b0a724a41405697ec55035dae66402",
4338                                           "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");
4339
4340                         test_htlc_output!(1,
4341                                           "3045022100d065569dcb94f090345402736385efeb8ea265131804beac06dd84d15dd2d6880220664feb0b4b2eb985fadb6ec7dc58c9334ea88ce599a9be760554a2d4b3b5d9f4",
4342                                           "3045022100914bb232cd4b2690ee3d6cb8c3713c4ac9c4fb925323068d8b07f67c8541f8d9022057152f5f1615b793d2d45aac7518989ae4fe970f28b9b5c77504799d25433f7f",
4343                                           "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");
4344
4345                         test_htlc_output!(2,
4346                                           "3045022100d4e69d363de993684eae7b37853c40722a4c1b4a7b588ad7b5d8a9b5006137a102207a069c628170ee34be5612747051bdcc087466dbaa68d5756ea81c10155aef18",
4347                                           "304402200e362443f7af830b419771e8e1614fc391db3a4eb799989abfc5ab26d6fcd032022039ab0cad1c14dfbe9446bf847965e56fe016e0cbcf719fd18c1bfbf53ecbd9f9",
4348                                           "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");
4349
4350                         test_htlc_output!(3,
4351                                           "30450221008ec888e36e4a4b3dc2ed6b823319855b2ae03006ca6ae0d9aa7e24bfc1d6f07102203b0f78885472a67ff4fe5916c0bb669487d659527509516fc3a08e87a2cc0a7c",
4352                                           "304402202c3e14282b84b02705dfd00a6da396c9fe8a8bcb1d3fdb4b20a4feba09440e8b02202b058b39aa9b0c865b22095edcd9ff1f71bbfe20aa4993755e54d042755ed0d5",
4353                                           "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");
4354                 }
4355
4356                 {
4357                         // commitment tx with five outputs untrimmed (minimum feerate)
4358                         chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
4359                         chan.feerate_per_kw = 2070;
4360
4361                         test_commitment!("3045022100f2377f7a67b7fc7f4e2c0c9e3a7de935c32417f5668eda31ea1db401b7dc53030220415fdbc8e91d0f735e70c21952342742e25249b0d062d43efbfc564499f37526",
4362                                          "30440220443cb07f650aebbba14b8bc8d81e096712590f524c5991ac0ed3bbc8fd3bd0c7022028a635f548e3ca64b19b69b1ea00f05b22752f91daf0b6dab78e62ba52eb7fd0",
4363                                          "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");
4364
4365                         assert_eq!(unsigned_tx.1.len(), 3);
4366
4367                         test_htlc_output!(0,
4368                                           "3045022100eed143b1ee4bed5dc3cde40afa5db3e7354cbf9c44054b5f713f729356f08cf7022077161d171c2bbd9badf3c9934de65a4918de03bbac1450f715275f75b103f891",
4369                                           "3045022100a0d043ed533e7fb1911e0553d31a8e2f3e6de19dbc035257f29d747c5e02f1f5022030cd38d8e84282175d49c1ebe0470db3ebd59768cf40780a784e248a43904fb8",
4370                                           "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");
4371
4372                         test_htlc_output!(1,
4373                                           "3044022071e9357619fd8d29a411dc053b326a5224c5d11268070e88ecb981b174747c7a02202b763ae29a9d0732fa8836dd8597439460b50472183f420021b768981b4f7cf6",
4374                                           "3045022100adb1d679f65f96178b59f23ed37d3b70443118f345224a07ecb043eee2acc157022034d24524fe857144a3bcfff3065a9994d0a6ec5f11c681e49431d573e242612d",
4375                                           "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");
4376
4377                         test_htlc_output!(2,
4378                                           "3045022100c9458a4d2cbb741705577deb0a890e5cb90ee141be0400d3162e533727c9cb2102206edcf765c5dc5e5f9b976ea8149bf8607b5a0efb30691138e1231302b640d2a4",
4379                                           "304402200831422aa4e1ee6d55e0b894201770a8f8817a189356f2d70be76633ffa6a6f602200dd1b84a4855dc6727dd46c98daae43dfc70889d1ba7ef0087529a57c06e5e04",
4380                                           "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");
4381                 }
4382
4383                 {
4384                         // commitment tx with five outputs untrimmed (maximum feerate)
4385                         chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
4386                         chan.feerate_per_kw = 2194;
4387
4388                         test_commitment!("3045022100d33c4e541aa1d255d41ea9a3b443b3b822ad8f7f86862638aac1f69f8f760577022007e2a18e6931ce3d3a804b1c78eda1de17dbe1fb7a95488c9a4ec86203953348",
4389                                          "304402203b1b010c109c2ecbe7feb2d259b9c4126bd5dc99ee693c422ec0a5781fe161ba0220571fe4e2c649dea9c7aaf7e49b382962f6a3494963c97d80fef9a430ca3f7061",
4390                                          "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");
4391
4392                         assert_eq!(unsigned_tx.1.len(), 3);
4393
4394                         test_htlc_output!(0,
4395                                           "30450221009ed2f0a67f99e29c3c8cf45c08207b765980697781bb727fe0b1416de0e7622902206052684229bc171419ed290f4b615c943f819c0262414e43c5b91dcf72ddcf44",
4396                                           "3044022004ad5f04ae69c71b3b141d4db9d0d4c38d84009fb3cfeeae6efdad414487a9a0022042d3fe1388c1ff517d1da7fb4025663d372c14728ed52dc88608363450ff6a2f",
4397                                           "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");
4398
4399                         test_htlc_output!(1,
4400                                           "30440220155d3b90c67c33a8321996a9be5b82431b0c126613be751d400669da9d5c696702204318448bcd48824439d2c6a70be6e5747446be47ff45977cf41672bdc9b6b12d",
4401                                           "304402201707050c870c1f77cc3ed58d6d71bf281de239e9eabd8ef0955bad0d7fe38dcc02204d36d80d0019b3a71e646a08fa4a5607761d341ae8be371946ebe437c289c915",
4402                                           "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");
4403
4404                         test_htlc_output!(2,
4405                                           "3045022100a12a9a473ece548584aabdd051779025a5ed4077c4b7aa376ec7a0b1645e5a48022039490b333f53b5b3e2ddde1d809e492cba2b3e5fc3a436cd3ffb4cd3d500fa5a",
4406                                           "3045022100ff200bc934ab26ce9a559e998ceb0aee53bc40368e114ab9d3054d9960546e2802202496856ca163ac12c143110b6b3ac9d598df7254f2e17b3b94c3ab5301f4c3b0",
4407                                           "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");
4408                 }
4409
4410                 {
4411                         // commitment tx with four outputs untrimmed (minimum feerate)
4412                         chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
4413                         chan.feerate_per_kw = 2195;
4414
4415                         test_commitment!("304402205e2f76d4657fb732c0dfc820a18a7301e368f5799e06b7828007633741bda6df0220458009ae59d0c6246065c419359e05eb2a4b4ef4a1b310cc912db44eb7924298",
4416                                          "304402203b12d44254244b8ff3bb4129b0920fd45120ab42f553d9976394b099d500c99e02205e95bb7a3164852ef0c48f9e0eaf145218f8e2c41251b231f03cbdc4f29a5429",
4417                                          "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");
4418
4419                         assert_eq!(unsigned_tx.1.len(), 2);
4420
4421                         test_htlc_output!(0,
4422                                           "3045022100a8a78fa1016a5c5c3704f2e8908715a3cef66723fb95f3132ec4d2d05cd84fb4022025ac49287b0861ec21932405f5600cbce94313dbde0e6c5d5af1b3366d8afbfc",
4423                                           "3045022100be6ae1977fd7b630a53623f3f25c542317ccfc2b971782802a4f1ef538eb22b402207edc4d0408f8f38fd3c7365d1cfc26511b7cd2d4fecd8b005fba3cd5bc704390",
4424                                           "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");
4425
4426                         test_htlc_output!(1,
4427                                           "3045022100e769cb156aa2f7515d126cef7a69968629620ce82afcaa9e210969de6850df4602200b16b3f3486a229a48aadde520dbee31ae340dbadaffae74fbb56681fef27b92",
4428                                           "30440220665b9cb4a978c09d1ca8977a534999bc8a49da624d0c5439451dd69cde1a003d022070eae0620f01f3c1bd029cc1488da13fb40fdab76f396ccd335479a11c5276d8",
4429                                           "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");
4430                 }
4431
4432                 {
4433                         // commitment tx with four outputs untrimmed (maximum feerate)
4434                         chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
4435                         chan.feerate_per_kw = 3702;
4436
4437                         test_commitment!("3045022100c1a3b0b60ca092ed5080121f26a74a20cec6bdee3f8e47bae973fcdceb3eda5502207d467a9873c939bf3aa758014ae67295fedbca52412633f7e5b2670fc7c381c1",
4438                                          "304402200e930a43c7951162dc15a2b7344f48091c74c70f7024e7116e900d8bcfba861c022066fa6cbda3929e21daa2e7e16a4b948db7e8919ef978402360d1095ffdaff7b0",
4439                                          "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");
4440
4441                         assert_eq!(unsigned_tx.1.len(), 2);
4442
4443                         test_htlc_output!(0,
4444                                           "3045022100dfb73b4fe961b31a859b2bb1f4f15cabab9265016dd0272323dc6a9e85885c54022059a7b87c02861ee70662907f25ce11597d7b68d3399443a831ae40e777b76bdb",
4445                                           "304402202765b9c9ece4f127fa5407faf66da4c5ce2719cdbe47cd3175fc7d48b482e43d02205605125925e07bad1e41c618a4b434d72c88a164981c4b8af5eaf4ee9142ec3a",
4446                                           "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");
4447
4448                         test_htlc_output!(1,
4449                                           "3045022100ea9dc2a7c3c3640334dab733bb4e036e32a3106dc707b24227874fa4f7da746802204d672f7ac0fe765931a8df10b81e53a3242dd32bd9dc9331eb4a596da87954e9",
4450                                           "30440220048a41c660c4841693de037d00a407810389f4574b3286afb7bc392a438fa3f802200401d71fa87c64fe621b49ac07e3bf85157ac680acb977124da28652cc7f1a5c",
4451                                           "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");
4452                 }
4453
4454                 {
4455                         // commitment tx with three outputs untrimmed (minimum feerate)
4456                         chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
4457                         chan.feerate_per_kw = 3703;
4458
4459                         test_commitment!("30450221008b7c191dd46893b67b628e618d2dc8e81169d38bade310181ab77d7c94c6675e02203b4dd131fd7c9deb299560983dcdc485545c98f989f7ae8180c28289f9e6bdb0",
4460                                          "3044022047305531dd44391dce03ae20f8735005c615eb077a974edb0059ea1a311857d602202e0ed6972fbdd1e8cb542b06e0929bc41b2ddf236e04cb75edd56151f4197506",
4461                                          "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");
4462
4463                         assert_eq!(unsigned_tx.1.len(), 1);
4464
4465                         test_htlc_output!(0,
4466                                           "3044022044f65cf833afdcb9d18795ca93f7230005777662539815b8a601eeb3e57129a902206a4bf3e53392affbba52640627defa8dc8af61c958c9e827b2798ab45828abdd",
4467                                           "3045022100b94d931a811b32eeb885c28ddcf999ae1981893b21dd1329929543fe87ce793002206370107fdd151c5f2384f9ceb71b3107c69c74c8ed5a28a94a4ab2d27d3b0724",
4468                                           "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");
4469                 }
4470
4471                 {
4472                         // commitment tx with three outputs untrimmed (maximum feerate)
4473                         chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
4474                         chan.feerate_per_kw = 4914;
4475
4476                         test_commitment!("304402206d6cb93969d39177a09d5d45b583f34966195b77c7e585cf47ac5cce0c90cefb022031d71ae4e33a4e80df7f981d696fbdee517337806a3c7138b7491e2cbb077a0e",
4477                                          "304402206a2679efa3c7aaffd2a447fd0df7aba8792858b589750f6a1203f9259173198a022008d52a0e77a99ab533c36206cb15ad7aeb2aa72b93d4b571e728cb5ec2f6fe26",
4478                                          "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");
4479
4480                         assert_eq!(unsigned_tx.1.len(), 1);
4481
4482                         test_htlc_output!(0,
4483                                           "3045022100fcb38506bfa11c02874092a843d0cc0a8613c23b639832564a5f69020cb0f6ba02206508b9e91eaa001425c190c68ee5f887e1ad5b1b314002e74db9dbd9e42dbecf",
4484                                           "304502210086e76b460ddd3cea10525fba298405d3fe11383e56966a5091811368362f689a02200f72ee75657915e0ede89c28709acd113ede9e1b7be520e3bc5cda425ecd6e68",
4485                                           "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");
4486                 }
4487
4488                 {
4489                         // commitment tx with two outputs untrimmed (minimum feerate)
4490                         chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
4491                         chan.feerate_per_kw = 4915;
4492
4493                         test_commitment!("304402200769ba89c7330dfa4feba447b6e322305f12ac7dac70ec6ba997ed7c1b598d0802204fe8d337e7fee781f9b7b1a06e580b22f4f79d740059560191d7db53f8765552",
4494                                          "3045022100a012691ba6cea2f73fa8bac37750477e66363c6d28813b0bb6da77c8eb3fb0270220365e99c51304b0b1a6ab9ea1c8500db186693e39ec1ad5743ee231b0138384b9",
4495                                          "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");
4496
4497                         assert_eq!(unsigned_tx.1.len(), 0);
4498                 }
4499
4500                 {
4501                         // commitment tx with two outputs untrimmed (maximum feerate)
4502                         chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
4503                         chan.feerate_per_kw = 9651180;
4504
4505                         test_commitment!("3044022037f83ff00c8e5fb18ae1f918ffc24e54581775a20ff1ae719297ef066c71caa9022039c529cccd89ff6c5ed1db799614533844bd6d101da503761c45c713996e3bbd",
4506                                          "30440220514f977bf7edc442de8ce43ace9686e5ebdc0f893033f13e40fb46c8b8c6e1f90220188006227d175f5c35da0b092c57bea82537aed89f7778204dc5bacf4f29f2b9",
4507                                          "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");
4508
4509                         assert_eq!(unsigned_tx.1.len(), 0);
4510                 }
4511
4512                 {
4513                         // commitment tx with one output untrimmed (minimum feerate)
4514                         chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
4515                         chan.feerate_per_kw = 9651181;
4516
4517                         test_commitment!("3044022064901950be922e62cbe3f2ab93de2b99f37cff9fc473e73e394b27f88ef0731d02206d1dfa227527b4df44a07599289e207d6fd9cca60c0365682dcd3deaf739567e",
4518                                          "3044022031a82b51bd014915fe68928d1abf4b9885353fb896cac10c3fdd88d7f9c7f2e00220716bda819641d2c63e65d3549b6120112e1aeaf1742eed94a471488e79e206b1",
4519                                          "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");
4520
4521                         assert_eq!(unsigned_tx.1.len(), 0);
4522                 }
4523
4524                 {
4525                         // commitment tx with fee greater than funder amount
4526                         chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
4527                         chan.feerate_per_kw = 9651936;
4528
4529                         test_commitment!("3044022064901950be922e62cbe3f2ab93de2b99f37cff9fc473e73e394b27f88ef0731d02206d1dfa227527b4df44a07599289e207d6fd9cca60c0365682dcd3deaf739567e",
4530                                          "3044022031a82b51bd014915fe68928d1abf4b9885353fb896cac10c3fdd88d7f9c7f2e00220716bda819641d2c63e65d3549b6120112e1aeaf1742eed94a471488e79e206b1",
4531                                          "02000000000101bef67e4e2fb9ddeeb3461973cd4c62abb35050b1add772995b820b584a488489000000000038b02b8001c0c62d0000000000160014ccf1af2f2aabee14bb40fa3851ab2301de8431100400473044022031a82b51bd014915fe68928d1abf4b9885353fb896cac10c3fdd88d7f9c7f2e00220716bda819641d2c63e65d3549b6120112e1aeaf1742eed94a471488e79e206b101473044022064901950be922e62cbe3f2ab93de2b99f37cff9fc473e73e394b27f88ef0731d02206d1dfa227527b4df44a07599289e207d6fd9cca60c0365682dcd3deaf739567e01475221023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb21030e9f7b623d2ccc7c9bd44d66d5ce21ce504c0acf6385a132cec6d3c39fa711c152ae3e195220");
4532
4533                         assert_eq!(unsigned_tx.1.len(), 0);
4534                 }
4535         }
4536
4537         #[test]
4538         fn test_per_commitment_secret_gen() {
4539                 // Test vectors from BOLT 3 Appendix D:
4540
4541                 let mut seed = [0; 32];
4542                 seed[0..32].clone_from_slice(&hex::decode("0000000000000000000000000000000000000000000000000000000000000000").unwrap());
4543                 assert_eq!(chan_utils::build_commitment_secret(seed, 281474976710655),
4544                            hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap()[..]);
4545
4546                 seed[0..32].clone_from_slice(&hex::decode("FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF").unwrap());
4547                 assert_eq!(chan_utils::build_commitment_secret(seed, 281474976710655),
4548                            hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap()[..]);
4549
4550                 assert_eq!(chan_utils::build_commitment_secret(seed, 0xaaaaaaaaaaa),
4551                            hex::decode("56f4008fb007ca9acf0e15b054d5c9fd12ee06cea347914ddbaed70d1c13a528").unwrap()[..]);
4552
4553                 assert_eq!(chan_utils::build_commitment_secret(seed, 0x555555555555),
4554                            hex::decode("9015daaeb06dba4ccc05b91b2f73bd54405f2be9f217fbacd3c5ac2e62327d31").unwrap()[..]);
4555
4556                 seed[0..32].clone_from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap());
4557                 assert_eq!(chan_utils::build_commitment_secret(seed, 1),
4558                            hex::decode("915c75942a26bb3a433a8ce2cb0427c29ec6c1775cfc78328b57f6ba7bfeaa9c").unwrap()[..]);
4559         }
4560
4561         #[test]
4562         fn test_key_derivation() {
4563                 // Test vectors from BOLT 3 Appendix E:
4564                 let secp_ctx = Secp256k1::new();
4565
4566                 let base_secret = SecretKey::from_slice(&hex::decode("000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f").unwrap()[..]).unwrap();
4567                 let per_commitment_secret = SecretKey::from_slice(&hex::decode("1f1e1d1c1b1a191817161514131211100f0e0d0c0b0a09080706050403020100").unwrap()[..]).unwrap();
4568
4569                 let base_point = PublicKey::from_secret_key(&secp_ctx, &base_secret);
4570                 assert_eq!(base_point.serialize()[..], hex::decode("036d6caac248af96f6afa7f904f550253a0f3ef3f5aa2fe6838a95b216691468e2").unwrap()[..]);
4571
4572                 let per_commitment_point = PublicKey::from_secret_key(&secp_ctx, &per_commitment_secret);
4573                 assert_eq!(per_commitment_point.serialize()[..], hex::decode("025f7117a78150fe2ef97db7cfc83bd57b2e2c0d0dd25eaf467a4a1c2a45ce1486").unwrap()[..]);
4574
4575                 assert_eq!(chan_utils::derive_public_key(&secp_ctx, &per_commitment_point, &base_point).unwrap().serialize()[..],
4576                                 hex::decode("0235f2dbfaa89b57ec7b055afe29849ef7ddfeb1cefdb9ebdc43f5494984db29e5").unwrap()[..]);
4577
4578                 assert_eq!(chan_utils::derive_private_key(&secp_ctx, &per_commitment_point, &base_secret).unwrap(),
4579                                 SecretKey::from_slice(&hex::decode("cbced912d3b21bf196a766651e436aff192362621ce317704ea2f75d87e7be0f").unwrap()[..]).unwrap());
4580
4581                 assert_eq!(chan_utils::derive_public_revocation_key(&secp_ctx, &per_commitment_point, &base_point).unwrap().serialize()[..],
4582                                 hex::decode("02916e326636d19c33f13e8c0c3a03dd157f332f3e99c317c141dd865eb01f8ff0").unwrap()[..]);
4583
4584                 assert_eq!(chan_utils::derive_private_revocation_key(&secp_ctx, &per_commitment_secret, &base_secret).unwrap(),
4585                                 SecretKey::from_slice(&hex::decode("d09ffff62ddb2297ab000cc85bcb4283fdeb6aa052affbc9dddcf33b61078110").unwrap()[..]).unwrap());
4586         }
4587 }