_ 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, |a, b| {
 939                         if let &Some(ref a_htlc) = a {
 940                                 if let &Some(ref b_htlc) = b {
 941                                         a_htlc.0.cltv_expiry.cmp(&b_htlc.0.cltv_expiry)
 942                                                 // Note that due to hash collisions, we have to have a fallback comparison
 943                                                 // here for fuzztarget mode (otherwise at least chanmon_fail_consistency
 944                                                 // may fail)!
 945                                                 .then(a_htlc.0.payment_hash.0.cmp(&b_htlc.0.payment_hash.0))
 946                                 // For non-HTLC outputs, if they're copying our SPK we don't really care if we
 947                                 // close the channel due to mismatches - they're doing something dumb:
 948                                 } else { cmp::Ordering::Equal }
 949                         } else { cmp::Ordering::Equal }
 950                 });
 951
 952                 let mut outputs: Vec<TxOut> = Vec::with_capacity(txouts.len());
 953                 let mut htlcs_included: Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)> = Vec::with_capacity(txouts.len() + included_dust_htlcs.len());
 954                 for (idx, mut out) in txouts.drain(..).enumerate() {
 955                         outputs.push(out.0);
 956                         if let Some((mut htlc, source_option)) = out.1.take() {
 957                                 htlc.transaction_output_index = Some(idx as u32);
 958                                 htlcs_included.push((htlc, source_option));
 959                         }
 960                 }
 961                 let non_dust_htlc_count = htlcs_included.len();
 962                 htlcs_included.append(&mut included_dust_htlcs);
 963
 964                 (Transaction {
 965                         version: 2,
 966                         lock_time: ((0x20 as u32) << 8*3) | ((obscured_commitment_transaction_number & 0xffffffu64) as u32),
 967                         input: txins,
 968                         output: outputs,
 969                 }, non_dust_htlc_count, htlcs_included)
 970         }
 971
 972         #[inline]
 973         fn get_closing_scriptpubkey(&self) -> Script {
 974                 let our_channel_close_key_hash = Hash160::hash(&self.shutdown_pubkey.serialize());
 975                 Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&our_channel_close_key_hash[..]).into_script()
 976         }
 977
 978         #[inline]
 979         fn get_closing_transaction_weight(a_scriptpubkey: &Script, b_scriptpubkey: &Script) -> u64 {
 980                 (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)
 981         }
 982
 983         #[inline]
 984         fn build_closing_transaction(&self, proposed_total_fee_satoshis: u64, skip_remote_output: bool) -> (Transaction, u64) {
 985                 let txins = {
 986                         let mut ins: Vec<TxIn> = Vec::new();
 987                         ins.push(TxIn {
 988                                 previous_output: self.channel_monitor.get_funding_txo().unwrap().into_bitcoin_outpoint(),
 989                                 script_sig: Script::new(),
 990                                 sequence: 0xffffffff,
 991                                 witness: Vec::new(),
 992                         });
 993                         ins
 994                 };
 995
 996                 assert!(self.pending_inbound_htlcs.is_empty());
 997                 assert!(self.pending_outbound_htlcs.is_empty());
 998                 let mut txouts: Vec<(TxOut, ())> = Vec::new();
 999
1000                 let mut total_fee_satoshis = proposed_total_fee_satoshis;
1001                 let value_to_self: i64 = (self.value_to_self_msat as i64) / 1000 - if self.channel_outbound { total_fee_satoshis as i64 } else { 0 };
1002                 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 };
1003
1004                 if value_to_self < 0 {
1005                         assert!(self.channel_outbound);
1006                         total_fee_satoshis += (-value_to_self) as u64;
1007                 } else if value_to_remote < 0 {
1008                         assert!(!self.channel_outbound);
1009                         total_fee_satoshis += (-value_to_remote) as u64;
1010                 }
1011
1012                 if !skip_remote_output && value_to_remote as u64 > self.our_dust_limit_satoshis {
1013                         txouts.push((TxOut {
1014                                 script_pubkey: self.their_shutdown_scriptpubkey.clone().unwrap(),
1015                                 value: value_to_remote as u64
1016                         }, ()));
1017                 }
1018
1019                 if value_to_self as u64 > self.our_dust_limit_satoshis {
1020                         txouts.push((TxOut {
1021                                 script_pubkey: self.get_closing_scriptpubkey(),
1022                                 value: value_to_self as u64
1023                         }, ()));
1024                 }
1025
1026                 transaction_utils::sort_outputs(&mut txouts, |_, _| { cmp::Ordering::Equal }); // Ordering doesnt matter if they used our pubkey...
1027
1028                 let mut outputs: Vec<TxOut> = Vec::new();
1029                 for out in txouts.drain(..) {
1030                         outputs.push(out.0);
1031                 }
1032
1033                 (Transaction {
1034                         version: 2,
1035                         lock_time: 0,
1036                         input: txins,
1037                         output: outputs,
1038                 }, total_fee_satoshis)
1039         }
1040
1041         #[inline]
1042         /// Creates a set of keys for build_commitment_transaction to generate a transaction which our
1043         /// counterparty will sign (ie DO NOT send signatures over a transaction created by this to
1044         /// our counterparty!)
1045         /// The result is a transaction which we can revoke ownership of (ie a "local" transaction)
1046         /// TODO Some magic rust shit to compile-time check this?
1047         fn build_local_transaction_keys(&self, commitment_number: u64) -> Result<TxCreationKeys, ChannelError> {
1048                 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &self.build_local_commitment_secret(commitment_number));
1049                 let delayed_payment_base = PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.delayed_payment_base_key);
1050                 let htlc_basepoint = PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.htlc_base_key);
1051
1052                 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"))
1053         }
1054
1055         #[inline]
1056         /// Creates a set of keys for build_commitment_transaction to generate a transaction which we
1057         /// will sign and send to our counterparty.
1058         /// If an Err is returned, it is a ChannelError::Close (for get_outbound_funding_created)
1059         fn build_remote_transaction_keys(&self) -> Result<TxCreationKeys, ChannelError> {
1060                 //TODO: Ensure that the payment_key derived here ends up in the library users' wallet as we
1061                 //may see payments to it!
1062                 let payment_basepoint = PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.payment_base_key);
1063                 let revocation_basepoint = PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.revocation_base_key);
1064                 let htlc_basepoint = PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.htlc_base_key);
1065
1066                 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"))
1067         }
1068
1069         /// Gets the redeemscript for the funding transaction output (ie the funding transaction output
1070         /// pays to get_funding_redeemscript().to_v0_p2wsh()).
1071         /// Panics if called before accept_channel/new_from_req
1072         pub fn get_funding_redeemscript(&self) -> Script {
1073                 let builder = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2);
1074                 let our_funding_key = PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.funding_key).serialize();
1075                 let their_funding_key = self.their_funding_pubkey.expect("get_funding_redeemscript only allowed after accept_channel").serialize();
1076                 if our_funding_key[..] < their_funding_key[..] {
1077                         builder.push_slice(&our_funding_key)
1078                                 .push_slice(&their_funding_key)
1079                 } else {
1080                         builder.push_slice(&their_funding_key)
1081                                 .push_slice(&our_funding_key)
1082                 }.push_opcode(opcodes::all::OP_PUSHNUM_2).push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script()
1083         }
1084
1085         fn sign_commitment_transaction(&self, tx: &mut Transaction, their_sig: &Signature) -> Signature {
1086                 if tx.input.len() != 1 {
1087                         panic!("Tried to sign commitment transaction that had input count != 1!");
1088                 }
1089                 if tx.input[0].witness.len() != 0 {
1090                         panic!("Tried to re-sign commitment transaction");
1091                 }
1092
1093                 let funding_redeemscript = self.get_funding_redeemscript();
1094
1095                 let sighash = hash_to_message!(&bip143::SighashComponents::new(&tx).sighash_all(&tx.input[0], &funding_redeemscript, self.channel_value_satoshis)[..]);
1096                 let our_sig = self.secp_ctx.sign(&sighash, &self.local_keys.funding_key);
1097
1098                 tx.input[0].witness.push(Vec::new()); // First is the multisig dummy
1099
1100                 let our_funding_key = PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.funding_key).serialize();
1101                 let their_funding_key = self.their_funding_pubkey.unwrap().serialize();
1102                 if our_funding_key[..] < their_funding_key[..] {
1103                         tx.input[0].witness.push(our_sig.serialize_der().to_vec());
1104                         tx.input[0].witness.push(their_sig.serialize_der().to_vec());
1105                 } else {
1106                         tx.input[0].witness.push(their_sig.serialize_der().to_vec());
1107                         tx.input[0].witness.push(our_sig.serialize_der().to_vec());
1108                 }
1109                 tx.input[0].witness[1].push(SigHashType::All as u8);
1110                 tx.input[0].witness[2].push(SigHashType::All as u8);
1111
1112                 tx.input[0].witness.push(funding_redeemscript.into_bytes());
1113
1114                 our_sig
1115         }
1116
1117         /// Builds the htlc-success or htlc-timeout transaction which spends a given HTLC output
1118         /// @local is used only to convert relevant internal structures which refer to remote vs local
1119         /// to decide value of outputs and direction of HTLCs.
1120         fn build_htlc_transaction(&self, prev_hash: &Sha256dHash, htlc: &HTLCOutputInCommitment, local: bool, keys: &TxCreationKeys, feerate_per_kw: u64) -> Transaction {
1121                 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)
1122         }
1123
1124         fn create_htlc_tx_signature(&self, tx: &Transaction, htlc: &HTLCOutputInCommitment, keys: &TxCreationKeys) -> Result<(Script, Signature, bool), ChannelError> {
1125                 if tx.input.len() != 1 {
1126                         panic!("Tried to sign HTLC transaction that had input count != 1!");
1127                 }
1128
1129                 let htlc_redeemscript = chan_utils::get_htlc_redeemscript(&htlc, &keys);
1130
1131                 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");
1132                 let sighash = hash_to_message!(&bip143::SighashComponents::new(&tx).sighash_all(&tx.input[0], &htlc_redeemscript, htlc.amount_msat / 1000)[..]);
1133                 let is_local_tx = PublicKey::from_secret_key(&self.secp_ctx, &our_htlc_key) == keys.a_htlc_key;
1134                 Ok((htlc_redeemscript, self.secp_ctx.sign(&sighash, &our_htlc_key), is_local_tx))
1135         }
1136
1137         /// Signs a transaction created by build_htlc_transaction. If the transaction is an
1138         /// HTLC-Success transaction (ie htlc.offered is false), preimage must be set!
1139         fn sign_htlc_transaction(&self, tx: &mut Transaction, their_sig: &Signature, preimage: &Option<PaymentPreimage>, htlc: &HTLCOutputInCommitment, keys: &TxCreationKeys) -> Result<Signature, ChannelError> {
1140                 if tx.input.len() != 1 {
1141                         panic!("Tried to sign HTLC transaction that had input count != 1!");
1142                 }
1143                 if tx.input[0].witness.len() != 0 {
1144                         panic!("Tried to re-sign HTLC transaction");
1145                 }
1146
1147                 let (htlc_redeemscript, our_sig, local_tx) = self.create_htlc_tx_signature(tx, htlc, keys)?;
1148
1149                 tx.input[0].witness.push(Vec::new()); // First is the multisig dummy
1150
1151                 if local_tx { // b, then a
1152                         tx.input[0].witness.push(their_sig.serialize_der().to_vec());
1153                         tx.input[0].witness.push(our_sig.serialize_der().to_vec());
1154                 } else {
1155                         tx.input[0].witness.push(our_sig.serialize_der().to_vec());
1156                         tx.input[0].witness.push(their_sig.serialize_der().to_vec());
1157                 }
1158                 tx.input[0].witness[1].push(SigHashType::All as u8);
1159                 tx.input[0].witness[2].push(SigHashType::All as u8);
1160
1161                 if htlc.offered {
1162                         tx.input[0].witness.push(Vec::new());
1163                 } else {
1164                         tx.input[0].witness.push(preimage.unwrap().0.to_vec());
1165                 }
1166
1167                 tx.input[0].witness.push(htlc_redeemscript.into_bytes());
1168
1169                 Ok(our_sig)
1170         }
1171
1172         /// Per HTLC, only one get_update_fail_htlc or get_update_fulfill_htlc call may be made.
1173         /// In such cases we debug_assert!(false) and return an IgnoreError. Thus, will always return
1174         /// Ok(_) if debug assertions are turned on and preconditions are met.
1175         fn get_update_fulfill_htlc(&mut self, htlc_id_arg: u64, payment_preimage_arg: PaymentPreimage) -> Result<(Option<msgs::UpdateFulfillHTLC>, Option<ChannelMonitor>), ChannelError> {
1176                 // Either ChannelFunded got set (which means it won't be unset) or there is no way any
1177                 // caller thought we could have something claimed (cause we wouldn't have accepted in an
1178                 // incoming HTLC anyway). If we got to ShutdownComplete, callers aren't allowed to call us,
1179                 // either.
1180                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
1181                         panic!("Was asked to fulfill an HTLC when channel was not in an operational state");
1182                 }
1183                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
1184
1185                 let payment_hash_calc = PaymentHash(Sha256::hash(&payment_preimage_arg.0[..]).into_inner());
1186
1187                 // ChannelManager may generate duplicate claims/fails due to HTLC update events from
1188                 // on-chain ChannelsMonitors during block rescan. Ideally we'd figure out a way to drop
1189                 // these, but for now we just have to treat them as normal.
1190
1191                 let mut pending_idx = std::usize::MAX;
1192                 for (idx, htlc) in self.pending_inbound_htlcs.iter().enumerate() {
1193                         if htlc.htlc_id == htlc_id_arg {
1194                                 assert_eq!(htlc.payment_hash, payment_hash_calc);
1195                                 match htlc.state {
1196                                         InboundHTLCState::Committed => {},
1197                                         InboundHTLCState::LocalRemoved(ref reason) => {
1198                                                 if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
1199                                                 } else {
1200                                                         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()));
1201                                                 }
1202                                                 return Ok((None, None));
1203                                         },
1204                                         _ => {
1205                                                 debug_assert!(false, "Have an inbound HTLC we tried to claim before it was fully committed to");
1206                                                 // Don't return in release mode here so that we can update channel_monitor
1207                                         }
1208                                 }
1209                                 pending_idx = idx;
1210                                 break;
1211                         }
1212                 }
1213                 if pending_idx == std::usize::MAX {
1214                         return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID"));
1215                 }
1216
1217                 // Now update local state:
1218                 //
1219                 // We have to put the payment_preimage in the channel_monitor right away here to ensure we
1220                 // can claim it even if the channel hits the chain before we see their next commitment.
1221                 self.channel_monitor.provide_payment_preimage(&payment_hash_calc, &payment_preimage_arg);
1222
1223                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32)) != 0 {
1224                         for pending_update in self.holding_cell_htlc_updates.iter() {
1225                                 match pending_update {
1226                                         &HTLCUpdateAwaitingACK::ClaimHTLC { htlc_id, .. } => {
1227                                                 if htlc_id_arg == htlc_id {
1228                                                         return Ok((None, None));
1229                                                 }
1230                                         },
1231                                         &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, .. } => {
1232                                                 if htlc_id_arg == htlc_id {
1233                                                         log_warn!(self, "Have preimage and want to fulfill HTLC with pending failure against channel {}", log_bytes!(self.channel_id()));
1234                                                         // TODO: We may actually be able to switch to a fulfill here, though its
1235                                                         // rare enough it may not be worth the complexity burden.
1236                                                         return Ok((None, Some(self.channel_monitor.clone())));
1237                                                 }
1238                                         },
1239                                         _ => {}
1240                                 }
1241                         }
1242                         log_trace!(self, "Adding HTLC claim to holding_cell! Current state: {}", self.channel_state);
1243                         self.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::ClaimHTLC {
1244                                 payment_preimage: payment_preimage_arg, htlc_id: htlc_id_arg,
1245                         });
1246                         return Ok((None, Some(self.channel_monitor.clone())));
1247                 }
1248
1249                 {
1250                         let htlc = &mut self.pending_inbound_htlcs[pending_idx];
1251                         if let InboundHTLCState::Committed = htlc.state {
1252                         } else {
1253                                 debug_assert!(false, "Have an inbound HTLC we tried to claim before it was fully committed to");
1254                                 return Ok((None, Some(self.channel_monitor.clone())));
1255                         }
1256                         log_trace!(self, "Upgrading HTLC {} to LocalRemoved with a Fulfill!", log_bytes!(htlc.payment_hash.0));
1257                         htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::Fulfill(payment_preimage_arg.clone()));
1258                 }
1259
1260                 Ok((Some(msgs::UpdateFulfillHTLC {
1261                         channel_id: self.channel_id(),
1262                         htlc_id: htlc_id_arg,
1263                         payment_preimage: payment_preimage_arg,
1264                 }), Some(self.channel_monitor.clone())))
1265         }
1266
1267         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> {
1268                 match self.get_update_fulfill_htlc(htlc_id, payment_preimage)? {
1269                         (Some(update_fulfill_htlc), _) => {
1270                                 let (commitment, monitor_update) = self.send_commitment_no_status_check()?;
1271                                 Ok((Some((update_fulfill_htlc, commitment)), Some(monitor_update)))
1272                         },
1273                         (None, Some(channel_monitor)) => Ok((None, Some(channel_monitor))),
1274                         (None, None) => Ok((None, None))
1275                 }
1276         }
1277
1278         /// Per HTLC, only one get_update_fail_htlc or get_update_fulfill_htlc call may be made.
1279         /// In such cases we debug_assert!(false) and return an IgnoreError. Thus, will always return
1280         /// Ok(_) if debug assertions are turned on and preconditions are met.
1281         pub fn get_update_fail_htlc(&mut self, htlc_id_arg: u64, err_packet: msgs::OnionErrorPacket) -> Result<Option<msgs::UpdateFailHTLC>, ChannelError> {
1282                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
1283                         panic!("Was asked to fail an HTLC when channel was not in an operational state");
1284                 }
1285                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
1286
1287                 // ChannelManager may generate duplicate claims/fails due to HTLC update events from
1288                 // on-chain ChannelsMonitors during block rescan. Ideally we'd figure out a way to drop
1289                 // these, but for now we just have to treat them as normal.
1290
1291                 let mut pending_idx = std::usize::MAX;
1292                 for (idx, htlc) in self.pending_inbound_htlcs.iter().enumerate() {
1293                         if htlc.htlc_id == htlc_id_arg {
1294                                 match htlc.state {
1295                                         InboundHTLCState::Committed => {},
1296                                         InboundHTLCState::LocalRemoved(_) => {
1297                                                 return Ok(None);
1298                                         },
1299                                         _ => {
1300                                                 debug_assert!(false, "Have an inbound HTLC we tried to claim before it was fully committed to");
1301                                                 return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID"));
1302                                         }
1303                                 }
1304                                 pending_idx = idx;
1305                         }
1306                 }
1307                 if pending_idx == std::usize::MAX {
1308                         return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID"));
1309                 }
1310
1311                 // Now update local state:
1312                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32)) != 0 {
1313                         for pending_update in self.holding_cell_htlc_updates.iter() {
1314                                 match pending_update {
1315                                         &HTLCUpdateAwaitingACK::ClaimHTLC { htlc_id, .. } => {
1316                                                 if htlc_id_arg == htlc_id {
1317                                                         return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID"));
1318                                                 }
1319                                         },
1320                                         &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, .. } => {
1321                                                 if htlc_id_arg == htlc_id {
1322                                                         return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID"));
1323                                                 }
1324                                         },
1325                                         _ => {}
1326                                 }
1327                         }
1328                         self.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::FailHTLC {
1329                                 htlc_id: htlc_id_arg,
1330                                 err_packet,
1331                         });
1332                         return Ok(None);
1333                 }
1334
1335                 {
1336                         let htlc = &mut self.pending_inbound_htlcs[pending_idx];
1337                         htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::FailRelay(err_packet.clone()));
1338                 }
1339
1340                 Ok(Some(msgs::UpdateFailHTLC {
1341                         channel_id: self.channel_id(),
1342                         htlc_id: htlc_id_arg,
1343                         reason: err_packet
1344                 }))
1345         }
1346
1347         // Message handlers:
1348
1349         pub fn accept_channel(&mut self, msg: &msgs::AcceptChannel, config: &UserConfig) -> Result<(), ChannelError> {
1350                 // Check sanity of message fields:
1351                 if !self.channel_outbound {
1352                         return Err(ChannelError::Close("Got an accept_channel message from an inbound peer"));
1353                 }
1354                 if self.channel_state != ChannelState::OurInitSent as u32 {
1355                         return Err(ChannelError::Close("Got an accept_channel message at a strange time"));
1356                 }
1357                 if msg.dust_limit_satoshis > 21000000 * 100000000 {
1358                         return Err(ChannelError::Close("Peer never wants payout outputs?"));
1359                 }
1360                 if msg.channel_reserve_satoshis > self.channel_value_satoshis {
1361                         return Err(ChannelError::Close("Bogus channel_reserve_satoshis"));
1362                 }
1363                 if msg.dust_limit_satoshis > msg.channel_reserve_satoshis {
1364                         return Err(ChannelError::Close("Bogus channel_reserve and dust_limit"));
1365                 }
1366                 if msg.channel_reserve_satoshis < self.our_dust_limit_satoshis {
1367                         return Err(ChannelError::Close("Peer never wants payout outputs?"));
1368                 }
1369                 if msg.dust_limit_satoshis > Channel::get_our_channel_reserve_satoshis(self.channel_value_satoshis) {
1370                         return Err(ChannelError::Close("Dust limit is bigger than our channel reverse"));
1371                 }
1372                 if msg.htlc_minimum_msat >= (self.channel_value_satoshis - msg.channel_reserve_satoshis) * 1000 {
1373                         return Err(ChannelError::Close("Minimum htlc value is full channel value"));
1374                 }
1375                 if msg.to_self_delay > MAX_LOCAL_BREAKDOWN_TIMEOUT {
1376                         return Err(ChannelError::Close("They wanted our payments to be delayed by a needlessly long period"));
1377                 }
1378                 if msg.max_accepted_htlcs < 1 {
1379                         return Err(ChannelError::Close("0 max_accepted_htlcs makes for a useless channel"));
1380                 }
1381                 if msg.max_accepted_htlcs > 483 {
1382                         return Err(ChannelError::Close("max_accepted_htlcs > 483"));
1383                 }
1384
1385                 // Now check against optional parameters as set by config...
1386                 if msg.htlc_minimum_msat > config.channel_limits.max_htlc_minimum_msat {
1387                         return Err(ChannelError::Close("htlc minimum msat is higher than the user specified limit"));
1388                 }
1389                 if msg.max_htlc_value_in_flight_msat < config.channel_limits.min_max_htlc_value_in_flight_msat {
1390                         return Err(ChannelError::Close("max htlc value in flight msat is less than the user specified limit"));
1391                 }
1392                 if msg.channel_reserve_satoshis > config.channel_limits.max_channel_reserve_satoshis {
1393                         return Err(ChannelError::Close("channel reserve satoshis is higher than the user specified limit"));
1394                 }
1395                 if msg.max_accepted_htlcs < config.channel_limits.min_max_accepted_htlcs {
1396                         return Err(ChannelError::Close("max accepted htlcs is less than the user specified limit"));
1397                 }
1398                 if msg.dust_limit_satoshis < config.channel_limits.min_dust_limit_satoshis {
1399                         return Err(ChannelError::Close("dust limit satoshis is less than the user specified limit"));
1400                 }
1401                 if msg.dust_limit_satoshis > config.channel_limits.max_dust_limit_satoshis {
1402                         return Err(ChannelError::Close("dust limit satoshis is greater than the user specified limit"));
1403                 }
1404                 if msg.minimum_depth > config.channel_limits.max_minimum_depth {
1405                         return Err(ChannelError::Close("We consider the minimum depth to be unreasonably large"));
1406                 }
1407
1408                 self.channel_monitor.set_their_base_keys(&msg.htlc_basepoint, &msg.delayed_payment_basepoint);
1409
1410                 self.their_dust_limit_satoshis = msg.dust_limit_satoshis;
1411                 self.their_max_htlc_value_in_flight_msat = cmp::min(msg.max_htlc_value_in_flight_msat, self.channel_value_satoshis * 1000);
1412                 self.their_channel_reserve_satoshis = msg.channel_reserve_satoshis;
1413                 self.their_htlc_minimum_msat = msg.htlc_minimum_msat;
1414                 self.their_to_self_delay = msg.to_self_delay;
1415                 self.their_max_accepted_htlcs = msg.max_accepted_htlcs;
1416                 self.minimum_depth = msg.minimum_depth;
1417                 self.their_funding_pubkey = Some(msg.funding_pubkey);
1418                 self.their_revocation_basepoint = Some(msg.revocation_basepoint);
1419                 self.their_payment_basepoint = Some(msg.payment_basepoint);
1420                 self.their_delayed_payment_basepoint = Some(msg.delayed_payment_basepoint);
1421                 self.their_htlc_basepoint = Some(msg.htlc_basepoint);
1422                 self.their_cur_commitment_point = Some(msg.first_per_commitment_point);
1423
1424                 let obscure_factor = self.get_commitment_transaction_number_obscure_factor();
1425                 self.channel_monitor.set_commitment_obscure_factor(obscure_factor);
1426                 self.channel_monitor.set_their_to_self_delay(msg.to_self_delay);
1427
1428                 self.channel_state = ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32;
1429
1430                 Ok(())
1431         }
1432
1433         fn funding_created_signature(&mut self, sig: &Signature) -> Result<(Transaction, Transaction, Signature, TxCreationKeys), ChannelError> {
1434                 let funding_script = self.get_funding_redeemscript();
1435
1436                 let local_keys = self.build_local_transaction_keys(self.cur_local_commitment_transaction_number)?;
1437                 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;
1438                 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)[..]);
1439
1440                 // They sign the "local" commitment transaction...
1441                 secp_check!(self.secp_ctx.verify(&local_sighash, &sig, &self.their_funding_pubkey.unwrap()), "Invalid funding_created signature from peer");
1442
1443                 // ...and we sign it, allowing us to broadcast the tx if we wish
1444                 self.sign_commitment_transaction(&mut local_initial_commitment_tx, sig);
1445
1446                 let remote_keys = self.build_remote_transaction_keys()?;
1447                 let remote_initial_commitment_tx = self.build_commitment_transaction(self.cur_remote_commitment_transaction_number, &remote_keys, false, false, self.feerate_per_kw).0;
1448                 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)[..]);
1449
1450                 // We sign the "remote" commitment transaction, allowing them to broadcast the tx if they wish.
1451                 Ok((remote_initial_commitment_tx, local_initial_commitment_tx, self.secp_ctx.sign(&remote_sighash, &self.local_keys.funding_key), local_keys))
1452         }
1453
1454         pub fn funding_created(&mut self, msg: &msgs::FundingCreated) -> Result<(msgs::FundingSigned, ChannelMonitor), ChannelError> {
1455                 if self.channel_outbound {
1456                         return Err(ChannelError::Close("Received funding_created for an outbound channel?"));
1457                 }
1458                 if self.channel_state != (ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32) {
1459                         // BOLT 2 says that if we disconnect before we send funding_signed we SHOULD NOT
1460                         // remember the channel, so it's safe to just send an error_message here and drop the
1461                         // channel.
1462                         return Err(ChannelError::Close("Received funding_created after we got the channel!"));
1463                 }
1464                 if self.channel_monitor.get_min_seen_secret() != (1 << 48) ||
1465                                 self.cur_remote_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER ||
1466                                 self.cur_local_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
1467                         panic!("Should not have advanced channel commitment tx numbers prior to funding_created");
1468                 }
1469
1470                 let funding_txo = OutPoint::new(msg.funding_txid, msg.funding_output_index);
1471                 let funding_txo_script = self.get_funding_redeemscript().to_v0_p2wsh();
1472                 self.channel_monitor.set_funding_info((funding_txo, funding_txo_script));
1473
1474                 let (remote_initial_commitment_tx, local_initial_commitment_tx, our_signature, local_keys) = match self.funding_created_signature(&msg.signature) {
1475                         Ok(res) => res,
1476                         Err(e) => {
1477                                 self.channel_monitor.unset_funding_info();
1478                                 return Err(e);
1479                         }
1480                 };
1481
1482                 // Now that we're past error-generating stuff, update our local state:
1483
1484                 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());
1485                 self.last_local_commitment_txn = vec![local_initial_commitment_tx.clone()];
1486                 self.channel_monitor.provide_latest_local_commitment_tx_info(local_initial_commitment_tx, local_keys, self.feerate_per_kw, Vec::new());
1487                 self.channel_state = ChannelState::FundingSent as u32;
1488                 self.channel_id = funding_txo.to_channel_id();
1489                 self.cur_remote_commitment_transaction_number -= 1;
1490                 self.cur_local_commitment_transaction_number -= 1;
1491
1492                 Ok((msgs::FundingSigned {
1493                         channel_id: self.channel_id,
1494                         signature: our_signature
1495                 }, self.channel_monitor.clone()))
1496         }
1497
1498         /// Handles a funding_signed message from the remote end.
1499         /// If this call is successful, broadcast the funding transaction (and not before!)
1500         pub fn funding_signed(&mut self, msg: &msgs::FundingSigned) -> Result<ChannelMonitor, ChannelError> {
1501                 if !self.channel_outbound {
1502                         return Err(ChannelError::Close("Received funding_signed for an inbound channel?"));
1503                 }
1504                 if self.channel_state != ChannelState::FundingCreated as u32 {
1505                         return Err(ChannelError::Close("Received funding_signed in strange state!"));
1506                 }
1507                 if self.channel_monitor.get_min_seen_secret() != (1 << 48) ||
1508                                 self.cur_remote_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER - 1 ||
1509                                 self.cur_local_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
1510                         panic!("Should not have advanced channel commitment tx numbers prior to funding_created");
1511                 }
1512
1513                 let funding_script = self.get_funding_redeemscript();
1514
1515                 let local_keys = self.build_local_transaction_keys(self.cur_local_commitment_transaction_number)?;
1516                 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;
1517                 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)[..]);
1518
1519                 // They sign the "local" commitment transaction, allowing us to broadcast the tx if we wish.
1520                 secp_check!(self.secp_ctx.verify(&local_sighash, &msg.signature, &self.their_funding_pubkey.unwrap()), "Invalid funding_signed signature from peer");
1521
1522                 self.sign_commitment_transaction(&mut local_initial_commitment_tx, &msg.signature);
1523                 self.channel_monitor.provide_latest_local_commitment_tx_info(local_initial_commitment_tx.clone(), local_keys, self.feerate_per_kw, Vec::new());
1524                 self.last_local_commitment_txn = vec![local_initial_commitment_tx];
1525                 self.channel_state = ChannelState::FundingSent as u32;
1526                 self.cur_local_commitment_transaction_number -= 1;
1527
1528                 Ok(self.channel_monitor.clone())
1529         }
1530
1531         pub fn funding_locked(&mut self, msg: &msgs::FundingLocked) -> Result<(), ChannelError> {
1532                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
1533                         return Err(ChannelError::Close("Peer sent funding_locked when we needed a channel_reestablish"));
1534                 }
1535
1536                 let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
1537
1538                 if non_shutdown_state == ChannelState::FundingSent as u32 {
1539                         self.channel_state |= ChannelState::TheirFundingLocked as u32;
1540                 } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::OurFundingLocked as u32) {
1541                         self.channel_state = ChannelState::ChannelFunded as u32 | (self.channel_state & MULTI_STATE_FLAGS);
1542                         self.channel_update_count += 1;
1543                 } else if self.channel_state & (ChannelState::ChannelFunded as u32) != 0 &&
1544                                 // Note that funding_signed/funding_created will have decremented both by 1!
1545                                 self.cur_local_commitment_transaction_number == INITIAL_COMMITMENT_NUMBER - 1 &&
1546                                 self.cur_remote_commitment_transaction_number == INITIAL_COMMITMENT_NUMBER - 1 {
1547                         if self.their_cur_commitment_point != Some(msg.next_per_commitment_point) {
1548                                 return Err(ChannelError::Close("Peer sent a reconnect funding_locked with a different point"));
1549                         }
1550                         // They probably disconnected/reconnected and re-sent the funding_locked, which is required
1551                         return Ok(());
1552                 } else {
1553                         return Err(ChannelError::Close("Peer sent a funding_locked at a strange time"));
1554                 }
1555
1556                 self.their_prev_commitment_point = self.their_cur_commitment_point;
1557                 self.their_cur_commitment_point = Some(msg.next_per_commitment_point);
1558                 Ok(())
1559         }
1560
1561         /// Returns (inbound_htlc_count, htlc_inbound_value_msat)
1562         fn get_inbound_pending_htlc_stats(&self) -> (u32, u64) {
1563                 let mut htlc_inbound_value_msat = 0;
1564                 for ref htlc in self.pending_inbound_htlcs.iter() {
1565                         htlc_inbound_value_msat += htlc.amount_msat;
1566                 }
1567                 (self.pending_inbound_htlcs.len() as u32, htlc_inbound_value_msat)
1568         }
1569
1570         /// Returns (outbound_htlc_count, htlc_outbound_value_msat) *including* pending adds in our
1571         /// holding cell.
1572         fn get_outbound_pending_htlc_stats(&self) -> (u32, u64) {
1573                 let mut htlc_outbound_value_msat = 0;
1574                 for ref htlc in self.pending_outbound_htlcs.iter() {
1575                         htlc_outbound_value_msat += htlc.amount_msat;
1576                 }
1577
1578                 let mut htlc_outbound_count = self.pending_outbound_htlcs.len();
1579                 for update in self.holding_cell_htlc_updates.iter() {
1580                         if let &HTLCUpdateAwaitingACK::AddHTLC { ref amount_msat, .. } = update {
1581                                 htlc_outbound_count += 1;
1582                                 htlc_outbound_value_msat += amount_msat;
1583                         }
1584                 }
1585
1586                 (htlc_outbound_count as u32, htlc_outbound_value_msat)
1587         }
1588
1589         pub fn update_add_htlc(&mut self, msg: &msgs::UpdateAddHTLC, pending_forward_state: PendingHTLCStatus) -> Result<(), ChannelError> {
1590                 if (self.channel_state & (ChannelState::ChannelFunded as u32 | ChannelState::RemoteShutdownSent as u32)) != (ChannelState::ChannelFunded as u32) {
1591                         return Err(ChannelError::Close("Got add HTLC message when channel was not in an operational state"));
1592                 }
1593                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
1594                         return Err(ChannelError::Close("Peer sent update_add_htlc when we needed a channel_reestablish"));
1595                 }
1596                 if msg.amount_msat > self.channel_value_satoshis * 1000 {
1597                         return Err(ChannelError::Close("Remote side tried to send more than the total value of the channel"));
1598                 }
1599                 if msg.amount_msat < self.our_htlc_minimum_msat {
1600                         return Err(ChannelError::Close("Remote side tried to send less than our minimum HTLC value"));
1601                 }
1602
1603                 let (inbound_htlc_count, htlc_inbound_value_msat) = self.get_inbound_pending_htlc_stats();
1604                 if inbound_htlc_count + 1 > OUR_MAX_HTLCS as u32 {
1605                         return Err(ChannelError::Close("Remote tried to push more than our max accepted HTLCs"));
1606                 }
1607                 //TODO: Spec is unclear if this is per-direction or in total (I assume per direction):
1608                 // Check our_max_htlc_value_in_flight_msat
1609                 if htlc_inbound_value_msat + msg.amount_msat > Channel::get_our_max_htlc_value_in_flight_msat(self.channel_value_satoshis) {
1610                         return Err(ChannelError::Close("Remote HTLC add would put them over their max HTLC value in flight"));
1611                 }
1612                 // Check our_channel_reserve_satoshis (we're getting paid, so they have to at least meet
1613                 // the reserve_satoshis we told them to always have as direct payment so that they lose
1614                 // something if we punish them for broadcasting an old state).
1615                 // Note that we don't really care about having a small/no to_remote output in our local
1616                 // commitment transactions, as the purpose of the channel reserve is to ensure we can
1617                 // punish *them* if they misbehave, so we discount any outbound HTLCs which will not be
1618                 // present in the next commitment transaction we send them (at least for fulfilled ones,
1619                 // failed ones won't modify value_to_self).
1620                 // Note that we will send HTLCs which another instance of rust-lightning would think
1621                 // violate the reserve value if we do not do this (as we forget inbound HTLCs from the
1622                 // Channel state once they will not be present in the next received commitment
1623                 // transaction).
1624                 let mut removed_outbound_total_msat = 0;
1625                 for ref htlc in self.pending_outbound_htlcs.iter() {
1626                         if let OutboundHTLCState::AwaitingRemoteRevokeToRemove(None) = htlc.state {
1627                                 removed_outbound_total_msat += htlc.amount_msat;
1628                         } else if let OutboundHTLCState::AwaitingRemovedRemoteRevoke(None) = htlc.state {
1629                                 removed_outbound_total_msat += htlc.amount_msat;
1630                         }
1631                 }
1632                 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 {
1633                         return Err(ChannelError::Close("Remote HTLC add would put them over their reserve value"));
1634                 }
1635                 if self.next_remote_htlc_id != msg.htlc_id {
1636                         return Err(ChannelError::Close("Remote skipped HTLC ID"));
1637                 }
1638                 if msg.cltv_expiry >= 500000000 {
1639                         return Err(ChannelError::Close("Remote provided CLTV expiry in seconds instead of block height"));
1640                 }
1641
1642                 //TODO: Check msg.cltv_expiry further? Do this in channel manager?
1643
1644                 if self.channel_state & ChannelState::LocalShutdownSent as u32 != 0 {
1645                         if let PendingHTLCStatus::Forward(_) = pending_forward_state {
1646                                 panic!("ChannelManager shouldn't be trying to add a forwardable HTLC after we've started closing");
1647                         }
1648                 }
1649
1650                 // Now update local state:
1651                 self.next_remote_htlc_id += 1;
1652                 self.pending_inbound_htlcs.push(InboundHTLCOutput {
1653                         htlc_id: msg.htlc_id,
1654                         amount_msat: msg.amount_msat,
1655                         payment_hash: msg.payment_hash,
1656                         cltv_expiry: msg.cltv_expiry,
1657                         state: InboundHTLCState::RemoteAnnounced(pending_forward_state),
1658                 });
1659                 Ok(())
1660         }
1661
1662         /// Marks an outbound HTLC which we have received update_fail/fulfill/malformed
1663         #[inline]
1664         fn mark_outbound_htlc_removed(&mut self, htlc_id: u64, check_preimage: Option<PaymentHash>, fail_reason: Option<HTLCFailReason>) -> Result<&HTLCSource, ChannelError> {
1665                 for htlc in self.pending_outbound_htlcs.iter_mut() {
1666                         if htlc.htlc_id == htlc_id {
1667                                 match check_preimage {
1668                                         None => {},
1669                                         Some(payment_hash) =>
1670                                                 if payment_hash != htlc.payment_hash {
1671                                                         return Err(ChannelError::Close("Remote tried to fulfill HTLC with an incorrect preimage"));
1672                                                 }
1673                                 };
1674                                 match htlc.state {
1675                                         OutboundHTLCState::LocalAnnounced(_) =>
1676                                                 return Err(ChannelError::Close("Remote tried to fulfill/fail HTLC before it had been committed")),
1677                                         OutboundHTLCState::Committed => {
1678                                                 htlc.state = OutboundHTLCState::RemoteRemoved(fail_reason);
1679                                         },
1680                                         OutboundHTLCState::AwaitingRemoteRevokeToRemove(_) | OutboundHTLCState::AwaitingRemovedRemoteRevoke(_) | OutboundHTLCState::RemoteRemoved(_) =>
1681                                                 return Err(ChannelError::Close("Remote tried to fulfill/fail HTLC that they'd already fulfilled/failed")),
1682                                 }
1683                                 return Ok(&htlc.source);
1684                         }
1685                 }
1686                 Err(ChannelError::Close("Remote tried to fulfill/fail an HTLC we couldn't find"))
1687         }
1688
1689         pub fn update_fulfill_htlc(&mut self, msg: &msgs::UpdateFulfillHTLC) -> Result<HTLCSource, ChannelError> {
1690                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
1691                         return Err(ChannelError::Close("Got fulfill 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_fulfill_htlc when we needed a channel_reestablish"));
1695                 }
1696
1697                 let payment_hash = PaymentHash(Sha256::hash(&msg.payment_preimage.0[..]).into_inner());
1698                 self.mark_outbound_htlc_removed(msg.htlc_id, Some(payment_hash), None).map(|source| source.clone())
1699         }
1700
1701         pub fn update_fail_htlc(&mut self, msg: &msgs::UpdateFailHTLC, 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 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_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 update_fail_malformed_htlc<'a>(&mut self, msg: &msgs::UpdateFailMalformedHTLC, fail_reason: HTLCFailReason) -> Result<(), ChannelError> {
1714                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
1715                         return Err(ChannelError::Close("Got fail malformed HTLC 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 update_fail_malformed_htlc when we needed a channel_reestablish"));
1719                 }
1720
1721                 self.mark_outbound_htlc_removed(msg.htlc_id, None, Some(fail_reason))?;
1722                 Ok(())
1723         }
1724
1725         pub fn commitment_signed(&mut self, msg: &msgs::CommitmentSigned, fee_estimator: &FeeEstimator) -> Result<(msgs::RevokeAndACK, Option<msgs::CommitmentSigned>, Option<msgs::ClosingSigned>, ChannelMonitor), ChannelError> {
1726                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
1727                         return Err(ChannelError::Close("Got commitment signed message when channel was not in an operational state"));
1728                 }
1729                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
1730                         return Err(ChannelError::Close("Peer sent commitment_signed when we needed a channel_reestablish"));
1731                 }
1732                 if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK == BOTH_SIDES_SHUTDOWN_MASK && self.last_sent_closing_fee.is_some() {
1733                         return Err(ChannelError::Close("Peer sent commitment_signed after we'd started exchanging closing_signeds"));
1734                 }
1735
1736                 let funding_script = self.get_funding_redeemscript();
1737
1738                 let local_keys = self.build_local_transaction_keys(self.cur_local_commitment_transaction_number)?;
1739
1740                 let mut update_fee = false;
1741                 let feerate_per_kw = if !self.channel_outbound && self.pending_update_fee.is_some() {
1742                         update_fee = true;
1743                         self.pending_update_fee.unwrap()
1744                 } else {
1745                         self.feerate_per_kw
1746                 };
1747
1748                 let mut local_commitment_tx = {
1749                         let mut commitment_tx = self.build_commitment_transaction(self.cur_local_commitment_transaction_number, &local_keys, true, false, feerate_per_kw);
1750                         let htlcs_cloned: Vec<_> = commitment_tx.2.drain(..).map(|htlc| (htlc.0, htlc.1.map(|h| h.clone()))).collect();
1751                         (commitment_tx.0, commitment_tx.1, htlcs_cloned)
1752                 };
1753                 let local_commitment_txid = local_commitment_tx.0.txid();
1754                 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)[..]);
1755                 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));
1756                 secp_check!(self.secp_ctx.verify(&local_sighash, &msg.signature, &self.their_funding_pubkey.unwrap()), "Invalid commitment tx signature from peer");
1757
1758                 //If channel fee was updated by funder confirm funder can afford the new fee rate when applied to the current local commitment transaction
1759                 if update_fee {
1760                         let num_htlcs = local_commitment_tx.1;
1761                         let total_fee: u64 = feerate_per_kw as u64 * (COMMITMENT_TX_BASE_WEIGHT + (num_htlcs as u64) * COMMITMENT_TX_WEIGHT_PER_HTLC) / 1000;
1762
1763                         if self.channel_value_satoshis - self.value_to_self_msat / 1000 < total_fee + self.their_channel_reserve_satoshis {
1764                                 return Err(ChannelError::Close("Funding remote cannot afford proposed new fee"));
1765                         }
1766                 }
1767
1768                 if msg.htlc_signatures.len() != local_commitment_tx.1 {
1769                         return Err(ChannelError::Close("Got wrong number of HTLC signatures from remote"));
1770                 }
1771
1772                 let mut new_local_commitment_txn = Vec::with_capacity(local_commitment_tx.1 + 1);
1773                 self.sign_commitment_transaction(&mut local_commitment_tx.0, &msg.signature);
1774                 new_local_commitment_txn.push(local_commitment_tx.0.clone());
1775
1776                 let mut htlcs_and_sigs = Vec::with_capacity(local_commitment_tx.2.len());
1777                 for (idx, (htlc, source)) in local_commitment_tx.2.drain(..).enumerate() {
1778                         if let Some(_) = htlc.transaction_output_index {
1779                                 let mut htlc_tx = self.build_htlc_transaction(&local_commitment_txid, &htlc, true, &local_keys, feerate_per_kw);
1780                                 let htlc_redeemscript = chan_utils::get_htlc_redeemscript(&htlc, &local_keys);
1781                                 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));
1782                                 let htlc_sighash = hash_to_message!(&bip143::SighashComponents::new(&htlc_tx).sighash_all(&htlc_tx.input[0], &htlc_redeemscript, htlc.amount_msat / 1000)[..]);
1783                                 secp_check!(self.secp_ctx.verify(&htlc_sighash, &msg.htlc_signatures[idx], &local_keys.b_htlc_key), "Invalid HTLC tx signature from peer");
1784                                 let htlc_sig = if htlc.offered {
1785                                         let htlc_sig = self.sign_htlc_transaction(&mut htlc_tx, &msg.htlc_signatures[idx], &None, &htlc, &local_keys)?;
1786                                         new_local_commitment_txn.push(htlc_tx);
1787                                         htlc_sig
1788                                 } else {
1789                                         self.create_htlc_tx_signature(&htlc_tx, &htlc, &local_keys)?.1
1790                                 };
1791                                 htlcs_and_sigs.push((htlc, Some((msg.htlc_signatures[idx], htlc_sig)), source));
1792                         } else {
1793                                 htlcs_and_sigs.push((htlc, None, source));
1794                         }
1795                 }
1796
1797                 let next_per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &self.build_local_commitment_secret(self.cur_local_commitment_transaction_number - 1));
1798                 let per_commitment_secret = chan_utils::build_commitment_secret(self.local_keys.commitment_seed, self.cur_local_commitment_transaction_number + 1);
1799
1800                 // Update state now that we've passed all the can-fail calls...
1801                 let mut need_our_commitment = false;
1802                 if !self.channel_outbound {
1803                         if let Some(fee_update) = self.pending_update_fee {
1804                                 self.feerate_per_kw = fee_update;
1805                                 // We later use the presence of pending_update_fee to indicate we should generate a
1806                                 // commitment_signed upon receipt of revoke_and_ack, so we can only set it to None
1807                                 // if we're not awaiting a revoke (ie will send a commitment_signed now).
1808                                 if (self.channel_state & ChannelState::AwaitingRemoteRevoke as u32) == 0 {
1809                                         need_our_commitment = true;
1810                                         self.pending_update_fee = None;
1811                                 }
1812                         }
1813                 }
1814
1815                 if self.channel_state & (ChannelState::MonitorUpdateFailed as u32) == 0 {
1816                         // This is a response to our post-monitor-failed unfreeze messages, so we can clear the
1817                         // monitor_pending_order requirement as we won't re-send the monitor_pending messages.
1818                         self.monitor_pending_order = None;
1819                 }
1820
1821                 self.channel_monitor.provide_latest_local_commitment_tx_info(local_commitment_tx.0, local_keys, self.feerate_per_kw, htlcs_and_sigs);
1822
1823                 for htlc in self.pending_inbound_htlcs.iter_mut() {
1824                         let new_forward = if let &InboundHTLCState::RemoteAnnounced(ref forward_info) = &htlc.state {
1825                                 Some(forward_info.clone())
1826                         } else { None };
1827                         if let Some(forward_info) = new_forward {
1828                                 htlc.state = InboundHTLCState::AwaitingRemoteRevokeToAnnounce(forward_info);
1829                                 need_our_commitment = true;
1830                         }
1831                 }
1832                 for htlc in self.pending_outbound_htlcs.iter_mut() {
1833                         if let Some(fail_reason) = if let &mut OutboundHTLCState::RemoteRemoved(ref mut fail_reason) = &mut htlc.state {
1834                                 Some(fail_reason.take())
1835                         } else { None } {
1836                                 htlc.state = OutboundHTLCState::AwaitingRemoteRevokeToRemove(fail_reason);
1837                                 need_our_commitment = true;
1838                         }
1839                 }
1840
1841                 self.cur_local_commitment_transaction_number -= 1;
1842                 self.last_local_commitment_txn = new_local_commitment_txn;
1843                 self.received_commitment_while_awaiting_raa = (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) != 0;
1844
1845                 if (self.channel_state & ChannelState::MonitorUpdateFailed as u32) != 0 {
1846                         // In case we initially failed monitor updating without requiring a response, we need
1847                         // to make sure the RAA gets sent first.
1848                         if !self.monitor_pending_commitment_signed {
1849                                 self.monitor_pending_order = Some(RAACommitmentOrder::RevokeAndACKFirst);
1850                         }
1851                         self.monitor_pending_revoke_and_ack = true;
1852                         if need_our_commitment && (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == 0 {
1853                                 // If we were going to send a commitment_signed after the RAA, go ahead and do all
1854                                 // the corresponding HTLC status updates so that get_last_commitment_update
1855                                 // includes the right HTLCs.
1856                                 // Note that this generates a monitor update that we ignore! This is OK since we
1857                                 // won't actually send the commitment_signed that generated the update to the other
1858                                 // side until the latest monitor has been pulled from us and stored.
1859                                 self.monitor_pending_commitment_signed = true;
1860                                 self.send_commitment_no_status_check()?;
1861                         }
1862                         // TODO: Call maybe_propose_first_closing_signed on restoration (or call it here and
1863                         // re-send the message on restoration)
1864                         return Err(ChannelError::Ignore("Previous monitor update failure prevented generation of RAA"));
1865                 }
1866
1867                 let (our_commitment_signed, monitor_update, closing_signed) = if need_our_commitment && (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == 0 {
1868                         // If we're AwaitingRemoteRevoke we can't send a new commitment here, but that's ok -
1869                         // we'll send one right away when we get the revoke_and_ack when we
1870                         // free_holding_cell_htlcs().
1871                         let (msg, monitor) = self.send_commitment_no_status_check()?;
1872                         (Some(msg), monitor, None)
1873                 } else if !need_our_commitment {
1874                         (None, self.channel_monitor.clone(), self.maybe_propose_first_closing_signed(fee_estimator))
1875                 } else { (None, self.channel_monitor.clone(), None) };
1876
1877                 Ok((msgs::RevokeAndACK {
1878                         channel_id: self.channel_id,
1879                         per_commitment_secret: per_commitment_secret,
1880                         next_per_commitment_point: next_per_commitment_point,
1881                 }, our_commitment_signed, closing_signed, monitor_update))
1882         }
1883
1884         /// Used to fulfill holding_cell_htlcs when we get a remote ack (or implicitly get it by them
1885         /// fulfilling or failing the last pending HTLC)
1886         fn free_holding_cell_htlcs(&mut self) -> Result<Option<(msgs::CommitmentUpdate, ChannelMonitor)>, ChannelError> {
1887                 assert_eq!(self.channel_state & ChannelState::MonitorUpdateFailed as u32, 0);
1888                 if self.holding_cell_htlc_updates.len() != 0 || self.holding_cell_update_fee.is_some() {
1889                         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 { "" });
1890
1891                         let mut htlc_updates = Vec::new();
1892                         mem::swap(&mut htlc_updates, &mut self.holding_cell_htlc_updates);
1893                         let mut update_add_htlcs = Vec::with_capacity(htlc_updates.len());
1894                         let mut update_fulfill_htlcs = Vec::with_capacity(htlc_updates.len());
1895                         let mut update_fail_htlcs = Vec::with_capacity(htlc_updates.len());
1896                         let mut err = None;
1897                         for htlc_update in htlc_updates.drain(..) {
1898                                 // Note that this *can* fail, though it should be due to rather-rare conditions on
1899                                 // fee races with adding too many outputs which push our total payments just over
1900                                 // the limit. In case it's less rare than I anticipate, we may want to revisit
1901                                 // handling this case better and maybe fulfilling some of the HTLCs while attempting
1902                                 // to rebalance channels.
1903                                 if err.is_some() { // We're back to AwaitingRemoteRevoke (or are about to fail the channel)
1904                                         self.holding_cell_htlc_updates.push(htlc_update);
1905                                 } else {
1906                                         match &htlc_update {
1907                                                 &HTLCUpdateAwaitingACK::AddHTLC {amount_msat, cltv_expiry, ref payment_hash, ref source, ref onion_routing_packet, ..} => {
1908                                                         match self.send_htlc(amount_msat, *payment_hash, cltv_expiry, source.clone(), onion_routing_packet.clone()) {
1909                                                                 Ok(update_add_msg_option) => update_add_htlcs.push(update_add_msg_option.unwrap()),
1910                                                                 Err(e) => {
1911                                                                         match e {
1912                                                                                 ChannelError::Ignore(ref msg) => {
1913                                                                                         log_info!(self, "Failed to send HTLC with payment_hash {} due to {}", log_bytes!(payment_hash.0), msg);
1914                                                                                 },
1915                                                                                 _ => {
1916                                                                                         log_info!(self, "Failed to send HTLC with payment_hash {} resulting in a channel closure during holding_cell freeing", log_bytes!(payment_hash.0));
1917                                                                                 },
1918                                                                         }
1919                                                                         err = Some(e);
1920                                                                 }
1921                                                         }
1922                                                 },
1923                                                 &HTLCUpdateAwaitingACK::ClaimHTLC { ref payment_preimage, htlc_id, .. } => {
1924                                                         match self.get_update_fulfill_htlc(htlc_id, *payment_preimage) {
1925                                                                 Ok(update_fulfill_msg_option) => update_fulfill_htlcs.push(update_fulfill_msg_option.0.unwrap()),
1926                                                                 Err(e) => {
1927                                                                         if let ChannelError::Ignore(_) = e {}
1928                                                                         else {
1929                                                                                 panic!("Got a non-IgnoreError action trying to fulfill holding cell HTLC");
1930                                                                         }
1931                                                                 }
1932                                                         }
1933                                                 },
1934                                                 &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, ref err_packet } => {
1935                                                         match self.get_update_fail_htlc(htlc_id, err_packet.clone()) {
1936                                                                 Ok(update_fail_msg_option) => update_fail_htlcs.push(update_fail_msg_option.unwrap()),
1937                                                                 Err(e) => {
1938                                                                         if let ChannelError::Ignore(_) = e {}
1939                                                                         else {
1940                                                                                 panic!("Got a non-IgnoreError action trying to fail holding cell HTLC");
1941                                                                         }
1942                                                                 }
1943                                                         }
1944                                                 },
1945                                         }
1946                                         if err.is_some() {
1947                                                 self.holding_cell_htlc_updates.push(htlc_update);
1948                                                 if let Some(ChannelError::Ignore(_)) = err {
1949                                                         // If we failed to add the HTLC, but got an Ignore error, we should
1950                                                         // still send the new commitment_signed, so reset the err to None.
1951                                                         err = None;
1952                                                 }
1953                                         }
1954                                 }
1955                         }
1956                         //TODO: Need to examine the type of err - if it's a fee issue or similar we may want to
1957                         //fail it back the route, if it's a temporary issue we can ignore it...
1958                         match err {
1959                                 None => {
1960                                         if update_add_htlcs.is_empty() && update_fulfill_htlcs.is_empty() && update_fail_htlcs.is_empty() && self.holding_cell_update_fee.is_none() {
1961                                                 // This should never actually happen and indicates we got some Errs back
1962                                                 // from update_fulfill_htlc/update_fail_htlc, but we handle it anyway in
1963                                                 // case there is some strange way to hit duplicate HTLC removes.
1964                                                 return Ok(None);
1965                                         }
1966                                         let update_fee = if let Some(feerate) = self.holding_cell_update_fee {
1967                                                         self.pending_update_fee = self.holding_cell_update_fee.take();
1968                                                         Some(msgs::UpdateFee {
1969                                                                 channel_id: self.channel_id,
1970                                                                 feerate_per_kw: feerate as u32,
1971                                                         })
1972                                                 } else {
1973                                                         None
1974                                                 };
1975                                         let (commitment_signed, monitor_update) = self.send_commitment_no_status_check()?;
1976                                         Ok(Some((msgs::CommitmentUpdate {
1977                                                 update_add_htlcs,
1978                                                 update_fulfill_htlcs,
1979                                                 update_fail_htlcs,
1980                                                 update_fail_malformed_htlcs: Vec::new(),
1981                                                 update_fee: update_fee,
1982                                                 commitment_signed,
1983                                         }, monitor_update)))
1984                                 },
1985                                 Some(e) => Err(e)
1986                         }
1987                 } else {
1988                         Ok(None)
1989                 }
1990         }
1991
1992         /// Handles receiving a remote's revoke_and_ack. Note that we may return a new
1993         /// commitment_signed message here in case we had pending outbound HTLCs to add which were
1994         /// waiting on this revoke_and_ack. The generation of this new commitment_signed may also fail,
1995         /// generating an appropriate error *after* the channel state has been updated based on the
1996         /// revoke_and_ack message.
1997         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> {
1998                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
1999                         return Err(ChannelError::Close("Got revoke/ACK message when channel was not in an operational state"));
2000                 }
2001                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2002                         return Err(ChannelError::Close("Peer sent revoke_and_ack when we needed a channel_reestablish"));
2003                 }
2004                 if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK == BOTH_SIDES_SHUTDOWN_MASK && self.last_sent_closing_fee.is_some() {
2005                         return Err(ChannelError::Close("Peer sent revoke_and_ack after we'd started exchanging closing_signeds"));
2006                 }
2007
2008                 if let Some(their_prev_commitment_point) = self.their_prev_commitment_point {
2009                         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 {
2010                                 return Err(ChannelError::Close("Got a revoke commitment secret which didn't correspond to their current pubkey"));
2011                         }
2012                 }
2013                 self.channel_monitor.provide_secret(self.cur_remote_commitment_transaction_number + 1, msg.per_commitment_secret)
2014                         .map_err(|e| ChannelError::Close(e.0))?;
2015
2016                 // Update state now that we've passed all the can-fail calls...
2017                 // (note that we may still fail to generate the new commitment_signed message, but that's
2018                 // OK, we step the channel here and *then* if the new generation fails we can fail the
2019                 // channel based on that, but stepping stuff here should be safe either way.
2020                 self.channel_state &= !(ChannelState::AwaitingRemoteRevoke as u32);
2021                 self.their_prev_commitment_point = self.their_cur_commitment_point;
2022                 self.their_cur_commitment_point = Some(msg.next_per_commitment_point);
2023                 self.cur_remote_commitment_transaction_number -= 1;
2024                 self.received_commitment_while_awaiting_raa = false;
2025                 if self.channel_state & (ChannelState::MonitorUpdateFailed as u32) == 0 {
2026                         // This is a response to our post-monitor-failed unfreeze messages, so we can clear the
2027                         // monitor_pending_order requirement as we won't re-send the monitor_pending messages.
2028                         self.monitor_pending_order = None;
2029                 }
2030
2031                 log_trace!(self, "Updating HTLCs on receipt of RAA...");
2032                 let mut to_forward_infos = Vec::new();
2033                 let mut revoked_htlcs = Vec::new();
2034                 let mut update_fail_htlcs = Vec::new();
2035                 let mut update_fail_malformed_htlcs = Vec::new();
2036                 let mut require_commitment = false;
2037                 let mut value_to_self_msat_diff: i64 = 0;
2038
2039                 {
2040                         // Take references explicitly so that we can hold multiple references to self.
2041                         let pending_inbound_htlcs: &mut Vec<_> = &mut self.pending_inbound_htlcs;
2042                         let pending_outbound_htlcs: &mut Vec<_> = &mut self.pending_outbound_htlcs;
2043                         let logger = LogHolder { logger: &self.logger };
2044
2045                         // We really shouldnt have two passes here, but retain gives a non-mutable ref (Rust bug)
2046                         pending_inbound_htlcs.retain(|htlc| {
2047                                 if let &InboundHTLCState::LocalRemoved(ref reason) = &htlc.state {
2048                                         log_trace!(logger, " ...removing inbound LocalRemoved {}", log_bytes!(htlc.payment_hash.0));
2049                                         if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
2050                                                 value_to_self_msat_diff += htlc.amount_msat as i64;
2051                                         }
2052                                         false
2053                                 } else { true }
2054                         });
2055                         pending_outbound_htlcs.retain(|htlc| {
2056                                 if let &OutboundHTLCState::AwaitingRemovedRemoteRevoke(ref fail_reason) = &htlc.state {
2057                                         log_trace!(logger, " ...removing outbound AwaitingRemovedRemoteRevoke {}", log_bytes!(htlc.payment_hash.0));
2058                                         if let Some(reason) = fail_reason.clone() { // We really want take() here, but, again, non-mut ref :(
2059                                                 revoked_htlcs.push((htlc.source.clone(), htlc.payment_hash, reason));
2060                                         } else {
2061                                                 // They fulfilled, so we sent them money
2062                                                 value_to_self_msat_diff -= htlc.amount_msat as i64;
2063                                         }
2064                                         false
2065                                 } else { true }
2066                         });
2067                         for htlc in pending_inbound_htlcs.iter_mut() {
2068                                 let swap = if let &InboundHTLCState::AwaitingRemoteRevokeToAnnounce(_) = &htlc.state {
2069                                         log_trace!(logger, " ...promoting inbound AwaitingRemoteRevokeToAnnounce {} to Committed", log_bytes!(htlc.payment_hash.0));
2070                                         true
2071                                 } else if let &InboundHTLCState::AwaitingAnnouncedRemoteRevoke(_) = &htlc.state {
2072                                         log_trace!(logger, " ...promoting inbound AwaitingAnnouncedRemoteRevoke {} to Committed", log_bytes!(htlc.payment_hash.0));
2073                                         true
2074                                 } else { false };
2075                                 if swap {
2076                                         let mut state = InboundHTLCState::Committed;
2077                                         mem::swap(&mut state, &mut htlc.state);
2078
2079                                         if let InboundHTLCState::AwaitingRemoteRevokeToAnnounce(forward_info) = state {
2080                                                 htlc.state = InboundHTLCState::AwaitingAnnouncedRemoteRevoke(forward_info);
2081                                                 require_commitment = true;
2082                                         } else if let InboundHTLCState::AwaitingAnnouncedRemoteRevoke(forward_info) = state {
2083                                                 match forward_info {
2084                                                         PendingHTLCStatus::Fail(fail_msg) => {
2085                                                                 require_commitment = true;
2086                                                                 match fail_msg {
2087                                                                         HTLCFailureMsg::Relay(msg) => {
2088                                                                                 htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::FailRelay(msg.reason.clone()));
2089                                                                                 update_fail_htlcs.push(msg)
2090                                                                         },
2091                                                                         HTLCFailureMsg::Malformed(msg) => {
2092                                                                                 htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::FailMalformed((msg.sha256_of_onion, msg.failure_code)));
2093                                                                                 update_fail_malformed_htlcs.push(msg)
2094                                                                         },
2095                                                                 }
2096                                                         },
2097                                                         PendingHTLCStatus::Forward(forward_info) => {
2098                                                                 to_forward_infos.push((forward_info, htlc.htlc_id));
2099                                                                 htlc.state = InboundHTLCState::Committed;
2100                                                         }
2101                                                 }
2102                                         }
2103                                 }
2104                         }
2105                         for htlc in pending_outbound_htlcs.iter_mut() {
2106                                 if let OutboundHTLCState::LocalAnnounced(_) = htlc.state {
2107                                         log_trace!(logger, " ...promoting outbound LocalAnnounced {} to Committed", log_bytes!(htlc.payment_hash.0));
2108                                         htlc.state = OutboundHTLCState::Committed;
2109                                 }
2110                                 if let Some(fail_reason) = if let &mut OutboundHTLCState::AwaitingRemoteRevokeToRemove(ref mut fail_reason) = &mut htlc.state {
2111                                         Some(fail_reason.take())
2112                                 } else { None } {
2113                                         log_trace!(logger, " ...promoting outbound AwaitingRemoteRevokeToRemove {} to AwaitingRemovedRemoteRevoke", log_bytes!(htlc.payment_hash.0));
2114                                         htlc.state = OutboundHTLCState::AwaitingRemovedRemoteRevoke(fail_reason);
2115                                         require_commitment = true;
2116                                 }
2117                         }
2118                 }
2119                 self.value_to_self_msat = (self.value_to_self_msat as i64 + value_to_self_msat_diff) as u64;
2120
2121                 if self.channel_outbound {
2122                         if let Some(feerate) = self.pending_update_fee.take() {
2123                                 self.feerate_per_kw = feerate;
2124                         }
2125                 } else {
2126                         if let Some(feerate) = self.pending_update_fee {
2127                                 // Because a node cannot send two commitment_signeds in a row without getting a
2128                                 // revoke_and_ack from us (as it would otherwise not know the per_commitment_point
2129                                 // it should use to create keys with) and because a node can't send a
2130                                 // commitment_signed without changes, checking if the feerate is equal to the
2131                                 // pending feerate update is sufficient to detect require_commitment.
2132                                 if feerate == self.feerate_per_kw {
2133                                         require_commitment = true;
2134                                         self.pending_update_fee = None;
2135                                 }
2136                         }
2137                 }
2138
2139                 if (self.channel_state & ChannelState::MonitorUpdateFailed as u32) == ChannelState::MonitorUpdateFailed as u32 {
2140                         // We can't actually generate a new commitment transaction (incl by freeing holding
2141                         // cells) while we can't update the monitor, so we just return what we have.
2142                         if require_commitment {
2143                                 self.monitor_pending_commitment_signed = true;
2144                                 // When the monitor updating is restored we'll call get_last_commitment_update(),
2145                                 // which does not update state, but we're definitely now awaiting a remote revoke
2146                                 // before we can step forward any more, so set it here.
2147                                 self.channel_state |= ChannelState::AwaitingRemoteRevoke as u32;
2148                         }
2149                         self.monitor_pending_forwards.append(&mut to_forward_infos);
2150                         self.monitor_pending_failures.append(&mut revoked_htlcs);
2151                         return Ok((None, Vec::new(), Vec::new(), None, self.channel_monitor.clone()));
2152                 }
2153
2154                 match self.free_holding_cell_htlcs()? {
2155                         Some(mut commitment_update) => {
2156                                 commitment_update.0.update_fail_htlcs.reserve(update_fail_htlcs.len());
2157                                 for fail_msg in update_fail_htlcs.drain(..) {
2158                                         commitment_update.0.update_fail_htlcs.push(fail_msg);
2159                                 }
2160                                 commitment_update.0.update_fail_malformed_htlcs.reserve(update_fail_malformed_htlcs.len());
2161                                 for fail_msg in update_fail_malformed_htlcs.drain(..) {
2162                                         commitment_update.0.update_fail_malformed_htlcs.push(fail_msg);
2163                                 }
2164                                 Ok((Some(commitment_update.0), to_forward_infos, revoked_htlcs, None, commitment_update.1))
2165                         },
2166                         None => {
2167                                 if require_commitment {
2168                                         let (commitment_signed, monitor_update) = self.send_commitment_no_status_check()?;
2169                                         Ok((Some(msgs::CommitmentUpdate {
2170                                                 update_add_htlcs: Vec::new(),
2171                                                 update_fulfill_htlcs: Vec::new(),
2172                                                 update_fail_htlcs,
2173                                                 update_fail_malformed_htlcs,
2174                                                 update_fee: None,
2175                                                 commitment_signed
2176                                         }), to_forward_infos, revoked_htlcs, None, monitor_update))
2177                                 } else {
2178                                         Ok((None, to_forward_infos, revoked_htlcs, self.maybe_propose_first_closing_signed(fee_estimator), self.channel_monitor.clone()))
2179                                 }
2180                         }
2181                 }
2182
2183         }
2184
2185         /// Adds a pending update to this channel. See the doc for send_htlc for
2186         /// further details on the optionness of the return value.
2187         /// You MUST call send_commitment prior to any other calls on this Channel
2188         fn send_update_fee(&mut self, feerate_per_kw: u64) -> Option<msgs::UpdateFee> {
2189                 if !self.channel_outbound {
2190                         panic!("Cannot send fee from inbound channel");
2191                 }
2192                 if !self.is_usable() {
2193                         panic!("Cannot update fee until channel is fully established and we haven't started shutting down");
2194                 }
2195                 if !self.is_live() {
2196                         panic!("Cannot update fee while peer is disconnected/we're awaiting a monitor update (ChannelManager should have caught this)");
2197                 }
2198
2199                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == (ChannelState::AwaitingRemoteRevoke as u32) {
2200                         self.holding_cell_update_fee = Some(feerate_per_kw);
2201                         return None;
2202                 }
2203
2204                 debug_assert!(self.pending_update_fee.is_none());
2205                 self.pending_update_fee = Some(feerate_per_kw);
2206
2207                 Some(msgs::UpdateFee {
2208                         channel_id: self.channel_id,
2209                         feerate_per_kw: feerate_per_kw as u32,
2210                 })
2211         }
2212
2213         pub fn send_update_fee_and_commit(&mut self, feerate_per_kw: u64) -> Result<Option<(msgs::UpdateFee, msgs::CommitmentSigned, ChannelMonitor)>, ChannelError> {
2214                 match self.send_update_fee(feerate_per_kw) {
2215                         Some(update_fee) => {
2216                                 let (commitment_signed, monitor_update) = self.send_commitment_no_status_check()?;
2217                                 Ok(Some((update_fee, commitment_signed, monitor_update)))
2218                         },
2219                         None => Ok(None)
2220                 }
2221         }
2222
2223         /// Removes any uncommitted HTLCs, to be used on peer disconnection, including any pending
2224         /// HTLCs that we intended to add but haven't as we were waiting on a remote revoke.
2225         /// Returns the set of PendingHTLCStatuses from remote uncommitted HTLCs (which we're
2226         /// implicitly dropping) and the payment_hashes of HTLCs we tried to add but are dropping.
2227         /// No further message handling calls may be made until a channel_reestablish dance has
2228         /// completed.
2229         pub fn remove_uncommitted_htlcs_and_mark_paused(&mut self) -> Vec<(HTLCSource, PaymentHash)> {
2230                 let mut outbound_drops = Vec::new();
2231
2232                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
2233                 if self.channel_state < ChannelState::FundingSent as u32 {
2234                         self.channel_state = ChannelState::ShutdownComplete as u32;
2235                         return outbound_drops;
2236                 }
2237                 // Upon reconnect we have to start the closing_signed dance over, but shutdown messages
2238                 // will be retransmitted.
2239                 self.last_sent_closing_fee = None;
2240
2241                 let mut inbound_drop_count = 0;
2242                 self.pending_inbound_htlcs.retain(|htlc| {
2243                         match htlc.state {
2244                                 InboundHTLCState::RemoteAnnounced(_) => {
2245                                         // They sent us an update_add_htlc but we never got the commitment_signed.
2246                                         // We'll tell them what commitment_signed we're expecting next and they'll drop
2247                                         // this HTLC accordingly
2248                                         inbound_drop_count += 1;
2249                                         false
2250                                 },
2251                                 InboundHTLCState::AwaitingRemoteRevokeToAnnounce(_)|InboundHTLCState::AwaitingAnnouncedRemoteRevoke(_) => {
2252                                         // We received a commitment_signed updating this HTLC and (at least hopefully)
2253                                         // sent a revoke_and_ack (which we can re-transmit) and have heard nothing
2254                                         // in response to it yet, so don't touch it.
2255                                         true
2256                                 },
2257                                 InboundHTLCState::Committed => true,
2258                                 InboundHTLCState::LocalRemoved(_) => {
2259                                         // We (hopefully) sent a commitment_signed updating this HTLC (which we can
2260                                         // re-transmit if needed) and they may have even sent a revoke_and_ack back
2261                                         // (that we missed). Keep this around for now and if they tell us they missed
2262                                         // the commitment_signed we can re-transmit the update then.
2263                                         true
2264                                 },
2265                         }
2266                 });
2267                 self.next_remote_htlc_id -= inbound_drop_count;
2268
2269                 for htlc in self.pending_outbound_htlcs.iter_mut() {
2270                         if let OutboundHTLCState::RemoteRemoved(_) = htlc.state {
2271                                 // They sent us an update to remove this but haven't yet sent the corresponding
2272                                 // commitment_signed, we need to move it back to Committed and they can re-send
2273                                 // the update upon reconnection.
2274                                 htlc.state = OutboundHTLCState::Committed;
2275                         }
2276                 }
2277
2278                 self.holding_cell_htlc_updates.retain(|htlc_update| {
2279                         match htlc_update {
2280                                 &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, ref source, .. } => {
2281                                         outbound_drops.push((source.clone(), payment_hash.clone()));
2282                                         false
2283                                 },
2284                                 &HTLCUpdateAwaitingACK::ClaimHTLC {..} | &HTLCUpdateAwaitingACK::FailHTLC {..} => true,
2285                         }
2286                 });
2287                 self.channel_state |= ChannelState::PeerDisconnected as u32;
2288                 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()));
2289                 outbound_drops
2290         }
2291
2292         /// Indicates that a ChannelMonitor update failed to be stored by the client and further
2293         /// updates are partially paused.
2294         /// This must be called immediately after the call which generated the ChannelMonitor update
2295         /// which failed, with the order argument set to the type of call it represented (ie a
2296         /// commitment update or a revoke_and_ack generation). The messages which were generated from
2297         /// that original call must *not* have been sent to the remote end, and must instead have been
2298         /// dropped. They will be regenerated when monitor_updating_restored is called.
2299         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)>) {
2300                 assert_eq!(self.channel_state & ChannelState::MonitorUpdateFailed as u32, 0);
2301                 self.monitor_pending_revoke_and_ack = resend_raa;
2302                 self.monitor_pending_commitment_signed = resend_commitment;
2303                 self.monitor_pending_order = Some(order);
2304                 assert!(self.monitor_pending_forwards.is_empty());
2305                 mem::swap(&mut pending_forwards, &mut self.monitor_pending_forwards);
2306                 assert!(self.monitor_pending_failures.is_empty());
2307                 mem::swap(&mut pending_fails, &mut self.monitor_pending_failures);
2308                 self.channel_state |= ChannelState::MonitorUpdateFailed as u32;
2309         }
2310
2311         /// Indicates that the latest ChannelMonitor update has been committed by the client
2312         /// successfully and we should restore normal operation. Returns messages which should be sent
2313         /// to the remote side.
2314         pub fn monitor_updating_restored(&mut self) -> (Option<msgs::RevokeAndACK>, Option<msgs::CommitmentUpdate>, RAACommitmentOrder, Vec<(PendingForwardHTLCInfo, u64)>, Vec<(HTLCSource, PaymentHash, HTLCFailReason)>) {
2315                 assert_eq!(self.channel_state & ChannelState::MonitorUpdateFailed as u32, ChannelState::MonitorUpdateFailed as u32);
2316                 self.channel_state &= !(ChannelState::MonitorUpdateFailed as u32);
2317
2318                 let mut forwards = Vec::new();
2319                 mem::swap(&mut forwards, &mut self.monitor_pending_forwards);
2320                 let mut failures = Vec::new();
2321                 mem::swap(&mut failures, &mut self.monitor_pending_failures);
2322
2323                 if self.channel_state & (ChannelState::PeerDisconnected as u32) != 0 {
2324                         // Leave monitor_pending_order so we can order our channel_reestablish responses
2325                         self.monitor_pending_revoke_and_ack = false;
2326                         self.monitor_pending_commitment_signed = false;
2327                         return (None, None, RAACommitmentOrder::RevokeAndACKFirst, forwards, failures);
2328                 }
2329
2330                 let raa = if self.monitor_pending_revoke_and_ack {
2331                         Some(self.get_last_revoke_and_ack())
2332                 } else { None };
2333                 let commitment_update = if self.monitor_pending_commitment_signed {
2334                         Some(self.get_last_commitment_update())
2335                 } else { None };
2336
2337                 self.monitor_pending_revoke_and_ack = false;
2338                 self.monitor_pending_commitment_signed = false;
2339                 let order = self.monitor_pending_order.clone().unwrap();
2340                 log_trace!(self, "Restored monitor updating resulting in {} commitment update and {} RAA, with {} first",
2341                         if commitment_update.is_some() { "a" } else { "no" },
2342                         if raa.is_some() { "an" } else { "no" },
2343                         match order { RAACommitmentOrder::CommitmentFirst => "commitment", RAACommitmentOrder::RevokeAndACKFirst => "RAA"});
2344                 (raa, commitment_update, order, forwards, failures)
2345         }
2346
2347         pub fn update_fee(&mut self, fee_estimator: &FeeEstimator, msg: &msgs::UpdateFee) -> Result<(), ChannelError> {
2348                 if self.channel_outbound {
2349                         return Err(ChannelError::Close("Non-funding remote tried to update channel fee"));
2350                 }
2351                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2352                         return Err(ChannelError::Close("Peer sent update_fee when we needed a channel_reestablish"));
2353                 }
2354                 Channel::check_remote_fee(fee_estimator, msg.feerate_per_kw)?;
2355                 self.pending_update_fee = Some(msg.feerate_per_kw as u64);
2356                 self.channel_update_count += 1;
2357                 Ok(())
2358         }
2359
2360         fn get_last_revoke_and_ack(&self) -> msgs::RevokeAndACK {
2361                 let next_per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &self.build_local_commitment_secret(self.cur_local_commitment_transaction_number));
2362                 let per_commitment_secret = chan_utils::build_commitment_secret(self.local_keys.commitment_seed, self.cur_local_commitment_transaction_number + 2);
2363                 msgs::RevokeAndACK {
2364                         channel_id: self.channel_id,
2365                         per_commitment_secret,
2366                         next_per_commitment_point,
2367                 }
2368         }
2369
2370         fn get_last_commitment_update(&self) -> msgs::CommitmentUpdate {
2371                 let mut update_add_htlcs = Vec::new();
2372                 let mut update_fulfill_htlcs = Vec::new();
2373                 let mut update_fail_htlcs = Vec::new();
2374                 let mut update_fail_malformed_htlcs = Vec::new();
2375
2376                 for htlc in self.pending_outbound_htlcs.iter() {
2377                         if let &OutboundHTLCState::LocalAnnounced(ref onion_packet) = &htlc.state {
2378                                 update_add_htlcs.push(msgs::UpdateAddHTLC {
2379                                         channel_id: self.channel_id(),
2380                                         htlc_id: htlc.htlc_id,
2381                                         amount_msat: htlc.amount_msat,
2382                                         payment_hash: htlc.payment_hash,
2383                                         cltv_expiry: htlc.cltv_expiry,
2384                                         onion_routing_packet: (**onion_packet).clone(),
2385                                 });
2386                         }
2387                 }
2388
2389                 for htlc in self.pending_inbound_htlcs.iter() {
2390                         if let &InboundHTLCState::LocalRemoved(ref reason) = &htlc.state {
2391                                 match reason {
2392                                         &InboundHTLCRemovalReason::FailRelay(ref err_packet) => {
2393                                                 update_fail_htlcs.push(msgs::UpdateFailHTLC {
2394                                                         channel_id: self.channel_id(),
2395                                                         htlc_id: htlc.htlc_id,
2396                                                         reason: err_packet.clone()
2397                                                 });
2398                                         },
2399                                         &InboundHTLCRemovalReason::FailMalformed((ref sha256_of_onion, ref failure_code)) => {
2400                                                 update_fail_malformed_htlcs.push(msgs::UpdateFailMalformedHTLC {
2401                                                         channel_id: self.channel_id(),
2402                                                         htlc_id: htlc.htlc_id,
2403                                                         sha256_of_onion: sha256_of_onion.clone(),
2404                                                         failure_code: failure_code.clone(),
2405                                                 });
2406                                         },
2407                                         &InboundHTLCRemovalReason::Fulfill(ref payment_preimage) => {
2408                                                 update_fulfill_htlcs.push(msgs::UpdateFulfillHTLC {
2409                                                         channel_id: self.channel_id(),
2410                                                         htlc_id: htlc.htlc_id,
2411                                                         payment_preimage: payment_preimage.clone(),
2412                                                 });
2413                                         },
2414                                 }
2415                         }
2416                 }
2417
2418                 log_trace!(self, "Regenerated latest commitment update with {} update_adds, {} update_fulfills, {} update_fails, and {} update_fail_malformeds",
2419                                 update_add_htlcs.len(), update_fulfill_htlcs.len(), update_fail_htlcs.len(), update_fail_malformed_htlcs.len());
2420                 msgs::CommitmentUpdate {
2421                         update_add_htlcs, update_fulfill_htlcs, update_fail_htlcs, update_fail_malformed_htlcs,
2422                         update_fee: None, //TODO: We need to support re-generating any update_fees in the last commitment_signed!
2423                         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,
2424                 }
2425         }
2426
2427         /// May panic if some calls other than message-handling calls (which will all Err immediately)
2428         /// have been called between remove_uncommitted_htlcs_and_mark_paused and this call.
2429         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> {
2430                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == 0 {
2431                         // While BOLT 2 doesn't indicate explicitly we should error this channel here, it
2432                         // almost certainly indicates we are going to end up out-of-sync in some way, so we
2433                         // just close here instead of trying to recover.
2434                         return Err(ChannelError::Close("Peer sent a loose channel_reestablish not after reconnect"));
2435                 }
2436
2437                 if msg.next_local_commitment_number >= INITIAL_COMMITMENT_NUMBER || msg.next_remote_commitment_number >= INITIAL_COMMITMENT_NUMBER ||
2438                         msg.next_local_commitment_number == 0 {
2439                         return Err(ChannelError::Close("Peer sent a garbage channel_reestablish"));
2440                 }
2441
2442                 // Go ahead and unmark PeerDisconnected as various calls we may make check for it (and all
2443                 // remaining cases either succeed or ErrorMessage-fail).
2444                 self.channel_state &= !(ChannelState::PeerDisconnected as u32);
2445
2446                 let shutdown_msg = if self.channel_state & (ChannelState::LocalShutdownSent as u32) != 0 {
2447                         Some(msgs::Shutdown {
2448                                 channel_id: self.channel_id,
2449                                 scriptpubkey: self.get_closing_scriptpubkey(),
2450                         })
2451                 } else { None };
2452
2453                 if self.channel_state & (ChannelState::FundingSent as u32) == ChannelState::FundingSent as u32 {
2454                         if self.channel_state & ChannelState::OurFundingLocked as u32 == 0 {
2455                                 if msg.next_remote_commitment_number != 0 {
2456                                         return Err(ChannelError::Close("Peer claimed they saw a revoke_and_ack but we haven't sent funding_locked yet"));
2457                                 }
2458                                 // Short circuit the whole handler as there is nothing we can resend them
2459                                 return Ok((None, None, None, None, RAACommitmentOrder::CommitmentFirst, shutdown_msg));
2460                         }
2461
2462                         // We have OurFundingLocked set!
2463                         let next_per_commitment_secret = self.build_local_commitment_secret(self.cur_local_commitment_transaction_number);
2464                         let next_per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &next_per_commitment_secret);
2465                         return Ok((Some(msgs::FundingLocked {
2466                                 channel_id: self.channel_id(),
2467                                 next_per_commitment_point: next_per_commitment_point,
2468                         }), None, None, None, RAACommitmentOrder::CommitmentFirst, shutdown_msg));
2469                 }
2470
2471                 let required_revoke = if msg.next_remote_commitment_number + 1 == INITIAL_COMMITMENT_NUMBER - self.cur_local_commitment_transaction_number {
2472                         // Remote isn't waiting on any RevokeAndACK from us!
2473                         // Note that if we need to repeat our FundingLocked we'll do that in the next if block.
2474                         None
2475                 } else if msg.next_remote_commitment_number + 1 == (INITIAL_COMMITMENT_NUMBER - 1) - self.cur_local_commitment_transaction_number {
2476                         if self.channel_state & (ChannelState::MonitorUpdateFailed as u32) != 0 {
2477                                 self.monitor_pending_revoke_and_ack = true;
2478                                 None
2479                         } else {
2480                                 Some(self.get_last_revoke_and_ack())
2481                         }
2482                 } else {
2483                         return Err(ChannelError::Close("Peer attempted to reestablish channel with a very old local commitment transaction"));
2484                 };
2485
2486                 // We increment cur_remote_commitment_transaction_number only upon receipt of
2487                 // revoke_and_ack, not on sending commitment_signed, so we add one if have
2488                 // AwaitingRemoteRevoke set, which indicates we sent a commitment_signed but haven't gotten
2489                 // the corresponding revoke_and_ack back yet.
2490                 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 };
2491
2492                 let resend_funding_locked = if msg.next_local_commitment_number == 1 && INITIAL_COMMITMENT_NUMBER - self.cur_local_commitment_transaction_number == 1 {
2493                         // We should never have to worry about MonitorUpdateFailed resending FundingLocked
2494                         let next_per_commitment_secret = self.build_local_commitment_secret(self.cur_local_commitment_transaction_number);
2495                         let next_per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &next_per_commitment_secret);
2496                         Some(msgs::FundingLocked {
2497                                 channel_id: self.channel_id(),
2498                                 next_per_commitment_point: next_per_commitment_point,
2499                         })
2500                 } else { None };
2501
2502                 let order = self.monitor_pending_order.clone().unwrap_or(if self.received_commitment_while_awaiting_raa {
2503                                 RAACommitmentOrder::CommitmentFirst
2504                         } else {
2505                                 RAACommitmentOrder::RevokeAndACKFirst
2506                         });
2507
2508                 if msg.next_local_commitment_number == our_next_remote_commitment_number {
2509                         if required_revoke.is_some() {
2510                                 log_debug!(self, "Reconnected channel {} with only lost outbound RAA", log_bytes!(self.channel_id()));
2511                         } else {
2512                                 log_debug!(self, "Reconnected channel {} with no loss", log_bytes!(self.channel_id()));
2513                         }
2514
2515                         if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::MonitorUpdateFailed as u32)) == 0 &&
2516                                         self.monitor_pending_order.is_none() { // monitor_pending_order indicates we're waiting on a response to a unfreeze
2517                                 // We're up-to-date and not waiting on a remote revoke (if we are our
2518                                 // channel_reestablish should result in them sending a revoke_and_ack), but we may
2519                                 // have received some updates while we were disconnected. Free the holding cell
2520                                 // now!
2521                                 match self.free_holding_cell_htlcs() {
2522                                         Err(ChannelError::Close(msg)) => return Err(ChannelError::Close(msg)),
2523                                         Err(ChannelError::Ignore(_)) => panic!("Got non-channel-failing result from free_holding_cell_htlcs"),
2524                                         Ok(Some((commitment_update, channel_monitor))) => return Ok((resend_funding_locked, required_revoke, Some(commitment_update), Some(channel_monitor), order, shutdown_msg)),
2525                                         Ok(None) => return Ok((resend_funding_locked, required_revoke, None, None, order, shutdown_msg)),
2526                                 }
2527                         } else {
2528                                 return Ok((resend_funding_locked, required_revoke, None, None, order, shutdown_msg));
2529                         }
2530                 } else if msg.next_local_commitment_number == our_next_remote_commitment_number - 1 {
2531                         if required_revoke.is_some() {
2532                                 log_debug!(self, "Reconnected channel {} with lost outbound RAA and lost remote commitment tx", log_bytes!(self.channel_id()));
2533                         } else {
2534                                 log_debug!(self, "Reconnected channel {} with only lost remote commitment tx", log_bytes!(self.channel_id()));
2535                         }
2536
2537                         if self.channel_state & (ChannelState::MonitorUpdateFailed as u32) != 0 {
2538                                 self.monitor_pending_commitment_signed = true;
2539                                 return Ok((resend_funding_locked, None, None, None, order, shutdown_msg));
2540                         }
2541
2542                         return Ok((resend_funding_locked, required_revoke, Some(self.get_last_commitment_update()), None, order, shutdown_msg));
2543                 } else {
2544                         return Err(ChannelError::Close("Peer attempted to reestablish channel with a very old remote commitment transaction"));
2545                 }
2546         }
2547
2548         fn maybe_propose_first_closing_signed(&mut self, fee_estimator: &FeeEstimator) -> Option<msgs::ClosingSigned> {
2549                 if !self.channel_outbound || !self.pending_inbound_htlcs.is_empty() || !self.pending_outbound_htlcs.is_empty() ||
2550                                 self.channel_state & (BOTH_SIDES_SHUTDOWN_MASK | ChannelState::AwaitingRemoteRevoke as u32) != BOTH_SIDES_SHUTDOWN_MASK ||
2551                                 self.last_sent_closing_fee.is_some() || self.pending_update_fee.is_some() {
2552                         return None;
2553                 }
2554
2555                 let mut proposed_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background);
2556                 if self.feerate_per_kw > proposed_feerate {
2557                         proposed_feerate = self.feerate_per_kw;
2558                 }
2559                 let tx_weight = Self::get_closing_transaction_weight(&self.get_closing_scriptpubkey(), self.their_shutdown_scriptpubkey.as_ref().unwrap());
2560                 let proposed_total_fee_satoshis = proposed_feerate * tx_weight / 1000;
2561
2562                 let (closing_tx, total_fee_satoshis) = self.build_closing_transaction(proposed_total_fee_satoshis, false);
2563                 let funding_redeemscript = self.get_funding_redeemscript();
2564                 let sighash = hash_to_message!(&bip143::SighashComponents::new(&closing_tx).sighash_all(&closing_tx.input[0], &funding_redeemscript, self.channel_value_satoshis)[..]);
2565
2566                 self.last_sent_closing_fee = Some((proposed_feerate, total_fee_satoshis));
2567                 Some(msgs::ClosingSigned {
2568                         channel_id: self.channel_id,
2569                         fee_satoshis: total_fee_satoshis,
2570                         signature: self.secp_ctx.sign(&sighash, &self.local_keys.funding_key),
2571                 })
2572         }
2573
2574         pub fn shutdown(&mut self, fee_estimator: &FeeEstimator, msg: &msgs::Shutdown) -> Result<(Option<msgs::Shutdown>, Option<msgs::ClosingSigned>, Vec<(HTLCSource, PaymentHash)>), ChannelError> {
2575                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2576                         return Err(ChannelError::Close("Peer sent shutdown when we needed a channel_reestablish"));
2577                 }
2578                 if self.channel_state < ChannelState::FundingSent as u32 {
2579                         // Spec says we should fail the connection, not the channel, but that's nonsense, there
2580                         // are plenty of reasons you may want to fail a channel pre-funding, and spec says you
2581                         // can do that via error message without getting a connection fail anyway...
2582                         return Err(ChannelError::Close("Peer sent shutdown pre-funding generation"));
2583                 }
2584                 for htlc in self.pending_inbound_htlcs.iter() {
2585                         if let InboundHTLCState::RemoteAnnounced(_) = htlc.state {
2586                                 return Err(ChannelError::Close("Got shutdown with remote pending HTLCs"));
2587                         }
2588                 }
2589                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
2590
2591                 // BOLT 2 says we must only send a scriptpubkey of certain standard forms, which are up to
2592                 // 34 bytes in length, so don't let the remote peer feed us some super fee-heavy script.
2593                 if self.channel_outbound && msg.scriptpubkey.len() > 34 {
2594                         return Err(ChannelError::Close("Got shutdown_scriptpubkey of absurd length from remote peer"));
2595                 }
2596
2597                 //Check shutdown_scriptpubkey form as BOLT says we must
2598                 if !msg.scriptpubkey.is_p2pkh() && !msg.scriptpubkey.is_p2sh() && !msg.scriptpubkey.is_v0_p2wpkh() && !msg.scriptpubkey.is_v0_p2wsh() {
2599                         return Err(ChannelError::Close("Got a nonstandard scriptpubkey from remote peer"));
2600                 }
2601
2602                 if self.their_shutdown_scriptpubkey.is_some() {
2603                         if Some(&msg.scriptpubkey) != self.their_shutdown_scriptpubkey.as_ref() {
2604                                 return Err(ChannelError::Close("Got shutdown request with a scriptpubkey which did not match their previous scriptpubkey"));
2605                         }
2606                 } else {
2607                         self.their_shutdown_scriptpubkey = Some(msg.scriptpubkey.clone());
2608                 }
2609
2610                 // From here on out, we may not fail!
2611
2612                 self.channel_state |= ChannelState::RemoteShutdownSent as u32;
2613                 self.channel_update_count += 1;
2614
2615                 // We can't send our shutdown until we've committed all of our pending HTLCs, but the
2616                 // remote side is unlikely to accept any new HTLCs, so we go ahead and "free" any holding
2617                 // cell HTLCs and return them to fail the payment.
2618                 self.holding_cell_update_fee = None;
2619                 let mut dropped_outbound_htlcs = Vec::with_capacity(self.holding_cell_htlc_updates.len());
2620                 self.holding_cell_htlc_updates.retain(|htlc_update| {
2621                         match htlc_update {
2622                                 &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, ref source, .. } => {
2623                                         dropped_outbound_htlcs.push((source.clone(), payment_hash.clone()));
2624                                         false
2625                                 },
2626                                 _ => true
2627                         }
2628                 });
2629                 // If we have any LocalAnnounced updates we'll probably just get back a update_fail_htlc
2630                 // immediately after the commitment dance, but we can send a Shutdown cause we won't send
2631                 // any further commitment updates after we set LocalShutdownSent.
2632
2633                 let our_shutdown = if (self.channel_state & ChannelState::LocalShutdownSent as u32) == ChannelState::LocalShutdownSent as u32 {
2634                         None
2635                 } else {
2636                         Some(msgs::Shutdown {
2637                                 channel_id: self.channel_id,
2638                                 scriptpubkey: self.get_closing_scriptpubkey(),
2639                         })
2640                 };
2641
2642                 self.channel_state |= ChannelState::LocalShutdownSent as u32;
2643                 self.channel_update_count += 1;
2644                 Ok((our_shutdown, self.maybe_propose_first_closing_signed(fee_estimator), dropped_outbound_htlcs))
2645         }
2646
2647         pub fn closing_signed(&mut self, fee_estimator: &FeeEstimator, msg: &msgs::ClosingSigned) -> Result<(Option<msgs::ClosingSigned>, Option<Transaction>), ChannelError> {
2648                 if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK != BOTH_SIDES_SHUTDOWN_MASK {
2649                         return Err(ChannelError::Close("Remote end sent us a closing_signed before both sides provided a shutdown"));
2650                 }
2651                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2652                         return Err(ChannelError::Close("Peer sent closing_signed when we needed a channel_reestablish"));
2653                 }
2654                 if !self.pending_inbound_htlcs.is_empty() || !self.pending_outbound_htlcs.is_empty() {
2655                         return Err(ChannelError::Close("Remote end sent us a closing_signed while there were still pending HTLCs"));
2656                 }
2657                 if msg.fee_satoshis > 21000000 * 10000000 { //this is required to stop potential overflow in build_closing_transaction
2658                         return Err(ChannelError::Close("Remote tried to send us a closing tx with > 21 million BTC fee"));
2659                 }
2660
2661                 let funding_redeemscript = self.get_funding_redeemscript();
2662                 let (mut closing_tx, used_total_fee) = self.build_closing_transaction(msg.fee_satoshis, false);
2663                 if used_total_fee != msg.fee_satoshis {
2664                         return Err(ChannelError::Close("Remote sent us a closing_signed with a fee greater than the value they can claim"));
2665                 }
2666                 let mut sighash = hash_to_message!(&bip143::SighashComponents::new(&closing_tx).sighash_all(&closing_tx.input[0], &funding_redeemscript, self.channel_value_satoshis)[..]);
2667
2668                 match self.secp_ctx.verify(&sighash, &msg.signature, &self.their_funding_pubkey.unwrap()) {
2669                         Ok(_) => {},
2670                         Err(_e) => {
2671                                 // The remote end may have decided to revoke their output due to inconsistent dust
2672                                 // limits, so check for that case by re-checking the signature here.
2673                                 closing_tx = self.build_closing_transaction(msg.fee_satoshis, true).0;
2674                                 sighash = hash_to_message!(&bip143::SighashComponents::new(&closing_tx).sighash_all(&closing_tx.input[0], &funding_redeemscript, self.channel_value_satoshis)[..]);
2675                                 secp_check!(self.secp_ctx.verify(&sighash, &msg.signature, &self.their_funding_pubkey.unwrap()), "Invalid closing tx signature from peer");
2676                         },
2677                 };
2678
2679                 if let Some((_, last_fee)) = self.last_sent_closing_fee {
2680                         if last_fee == msg.fee_satoshis {
2681                                 self.sign_commitment_transaction(&mut closing_tx, &msg.signature);
2682                                 self.channel_state = ChannelState::ShutdownComplete as u32;
2683                                 self.channel_update_count += 1;
2684                                 return Ok((None, Some(closing_tx)));
2685                         }
2686                 }
2687
2688                 macro_rules! propose_new_feerate {
2689                         ($new_feerate: expr) => {
2690                                 let closing_tx_max_weight = Self::get_closing_transaction_weight(&self.get_closing_scriptpubkey(), self.their_shutdown_scriptpubkey.as_ref().unwrap());
2691                                 let (closing_tx, used_total_fee) = self.build_closing_transaction($new_feerate * closing_tx_max_weight / 1000, false);
2692                                 sighash = hash_to_message!(&bip143::SighashComponents::new(&closing_tx).sighash_all(&closing_tx.input[0], &funding_redeemscript, self.channel_value_satoshis)[..]);
2693                                 let our_sig = self.secp_ctx.sign(&sighash, &self.local_keys.funding_key);
2694                                 self.last_sent_closing_fee = Some(($new_feerate, used_total_fee));
2695                                 return Ok((Some(msgs::ClosingSigned {
2696                                         channel_id: self.channel_id,
2697                                         fee_satoshis: used_total_fee,
2698                                         signature: our_sig,
2699                                 }), None))
2700                         }
2701                 }
2702
2703                 let proposed_sat_per_kw = msg.fee_satoshis * 1000 / closing_tx.get_weight();
2704                 if self.channel_outbound {
2705                         let our_max_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Normal);
2706                         if proposed_sat_per_kw > our_max_feerate {
2707                                 if let Some((last_feerate, _)) = self.last_sent_closing_fee {
2708                                         if our_max_feerate <= last_feerate {
2709                                                 return Err(ChannelError::Close("Unable to come to consensus about closing feerate, remote wanted something higher than our Normal feerate"));
2710                                         }
2711                                 }
2712                                 propose_new_feerate!(our_max_feerate);
2713                         }
2714                 } else {
2715                         let our_min_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background);
2716                         if proposed_sat_per_kw < our_min_feerate {
2717                                 if let Some((last_feerate, _)) = self.last_sent_closing_fee {
2718                                         if our_min_feerate >= last_feerate {
2719                                                 return Err(ChannelError::Close("Unable to come to consensus about closing feerate, remote wanted something lower than our Background feerate"));
2720                                         }
2721                                 }
2722                                 propose_new_feerate!(our_min_feerate);
2723                         }
2724                 }
2725
2726                 let our_sig = self.sign_commitment_transaction(&mut closing_tx, &msg.signature);
2727                 self.channel_state = ChannelState::ShutdownComplete as u32;
2728                 self.channel_update_count += 1;
2729
2730                 Ok((Some(msgs::ClosingSigned {
2731                         channel_id: self.channel_id,
2732                         fee_satoshis: msg.fee_satoshis,
2733                         signature: our_sig,
2734                 }), Some(closing_tx)))
2735         }
2736
2737         // Public utilities:
2738
2739         pub fn channel_id(&self) -> [u8; 32] {
2740                 self.channel_id
2741         }
2742
2743         /// Gets the "user_id" value passed into the construction of this channel. It has no special
2744         /// meaning and exists only to allow users to have a persistent identifier of a channel.
2745         pub fn get_user_id(&self) -> u64 {
2746                 self.user_id
2747         }
2748
2749         /// May only be called after funding has been initiated (ie is_funding_initiated() is true)
2750         pub fn channel_monitor(&self) -> ChannelMonitor {
2751                 if self.channel_state < ChannelState::FundingCreated as u32 {
2752                         panic!("Can't get a channel monitor until funding has been created");
2753                 }
2754                 self.channel_monitor.clone()
2755         }
2756
2757         /// Guaranteed to be Some after both FundingLocked messages have been exchanged (and, thus,
2758         /// is_usable() returns true).
2759         /// Allowed in any state (including after shutdown)
2760         pub fn get_short_channel_id(&self) -> Option<u64> {
2761                 self.short_channel_id
2762         }
2763
2764         /// Returns the funding_txo we either got from our peer, or were given by
2765         /// get_outbound_funding_created.
2766         pub fn get_funding_txo(&self) -> Option<OutPoint> {
2767                 self.channel_monitor.get_funding_txo()
2768         }
2769
2770         /// Allowed in any state (including after shutdown)
2771         pub fn get_their_node_id(&self) -> PublicKey {
2772                 self.their_node_id
2773         }
2774
2775         /// Allowed in any state (including after shutdown)
2776         pub fn get_our_htlc_minimum_msat(&self) -> u64 {
2777                 self.our_htlc_minimum_msat
2778         }
2779
2780         /// Allowed in any state (including after shutdown)
2781         pub fn get_their_htlc_minimum_msat(&self) -> u64 {
2782                 self.our_htlc_minimum_msat
2783         }
2784
2785         pub fn get_value_satoshis(&self) -> u64 {
2786                 self.channel_value_satoshis
2787         }
2788
2789         pub fn get_fee_proportional_millionths(&self) -> u32 {
2790                 self.config.fee_proportional_millionths
2791         }
2792
2793         #[cfg(test)]
2794         pub fn get_feerate(&self) -> u64 {
2795                 self.feerate_per_kw
2796         }
2797
2798         pub fn get_cur_local_commitment_transaction_number(&self) -> u64 {
2799                 self.cur_local_commitment_transaction_number + 1
2800         }
2801
2802         pub fn get_cur_remote_commitment_transaction_number(&self) -> u64 {
2803                 self.cur_remote_commitment_transaction_number + 1 - if self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32) != 0 { 1 } else { 0 }
2804         }
2805
2806         pub fn get_revoked_remote_commitment_transaction_number(&self) -> u64 {
2807                 self.cur_remote_commitment_transaction_number + 2
2808         }
2809
2810         //TODO: Testing purpose only, should be changed in another way after #81
2811         #[cfg(test)]
2812         pub fn get_local_keys(&self) -> &ChannelKeys {
2813                 &self.local_keys
2814         }
2815
2816         #[cfg(test)]
2817         pub fn get_value_stat(&self) -> ChannelValueStat {
2818                 ChannelValueStat {
2819                         value_to_self_msat: self.value_to_self_msat,
2820                         channel_value_msat: self.channel_value_satoshis * 1000,
2821                         channel_reserve_msat: self.their_channel_reserve_satoshis * 1000,
2822                         pending_outbound_htlcs_amount_msat: self.pending_outbound_htlcs.iter().map(|ref h| h.amount_msat).sum::<u64>(),
2823                         pending_inbound_htlcs_amount_msat: self.pending_inbound_htlcs.iter().map(|ref h| h.amount_msat).sum::<u64>(),
2824                         holding_cell_outbound_amount_msat: {
2825                                 let mut res = 0;
2826                                 for h in self.holding_cell_htlc_updates.iter() {
2827                                         match h {
2828                                                 &HTLCUpdateAwaitingACK::AddHTLC{amount_msat, .. } => {
2829                                                         res += amount_msat;
2830                                                 }
2831                                                 _ => {}
2832                                         }
2833                                 }
2834                                 res
2835                         },
2836                         their_max_htlc_value_in_flight_msat: self.their_max_htlc_value_in_flight_msat,
2837                 }
2838         }
2839
2840         /// Allowed in any state (including after shutdown)
2841         pub fn get_channel_update_count(&self) -> u32 {
2842                 self.channel_update_count
2843         }
2844
2845         pub fn should_announce(&self) -> bool {
2846                 self.config.announced_channel
2847         }
2848
2849         pub fn is_outbound(&self) -> bool {
2850                 self.channel_outbound
2851         }
2852
2853         /// Gets the fee we'd want to charge for adding an HTLC output to this Channel
2854         /// Allowed in any state (including after shutdown)
2855         pub fn get_our_fee_base_msat(&self, fee_estimator: &FeeEstimator) -> u32 {
2856                 // For lack of a better metric, we calculate what it would cost to consolidate the new HTLC
2857                 // output value back into a transaction with the regular channel output:
2858
2859                 // the fee cost of the HTLC-Success/HTLC-Timeout transaction:
2860                 let mut res = self.feerate_per_kw * cmp::max(HTLC_TIMEOUT_TX_WEIGHT, HTLC_SUCCESS_TX_WEIGHT) / 1000;
2861
2862                 if self.channel_outbound {
2863                         // + the marginal fee increase cost to us in the commitment transaction:
2864                         res += self.feerate_per_kw * COMMITMENT_TX_WEIGHT_PER_HTLC / 1000;
2865                 }
2866
2867                 // + the marginal cost of an input which spends the HTLC-Success/HTLC-Timeout output:
2868                 res += fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Normal) * SPENDING_INPUT_FOR_A_OUTPUT_WEIGHT / 1000;
2869
2870                 res as u32
2871         }
2872
2873         /// Returns true if we've ever received a message from the remote end for this Channel
2874         pub fn have_received_message(&self) -> bool {
2875                 self.channel_state > (ChannelState::OurInitSent as u32)
2876         }
2877
2878         /// Returns true if this channel is fully established and not known to be closing.
2879         /// Allowed in any state (including after shutdown)
2880         pub fn is_usable(&self) -> bool {
2881                 let mask = ChannelState::ChannelFunded as u32 | BOTH_SIDES_SHUTDOWN_MASK;
2882                 (self.channel_state & mask) == (ChannelState::ChannelFunded as u32)
2883         }
2884
2885         /// Returns true if this channel is currently available for use. This is a superset of
2886         /// is_usable() and considers things like the channel being temporarily disabled.
2887         /// Allowed in any state (including after shutdown)
2888         pub fn is_live(&self) -> bool {
2889                 self.is_usable() && (self.channel_state & (ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32) == 0)
2890         }
2891
2892         /// Returns true if this channel has been marked as awaiting a monitor update to move forward.
2893         /// Allowed in any state (including after shutdown)
2894         pub fn is_awaiting_monitor_update(&self) -> bool {
2895                 (self.channel_state & ChannelState::MonitorUpdateFailed as u32) != 0
2896         }
2897
2898         /// Returns true if funding_created was sent/received.
2899         pub fn is_funding_initiated(&self) -> bool {
2900                 self.channel_state >= ChannelState::FundingCreated as u32
2901         }
2902
2903         /// Returns true if this channel is fully shut down. True here implies that no further actions
2904         /// may/will be taken on this channel, and thus this object should be freed. Any future changes
2905         /// will be handled appropriately by the chain monitor.
2906         pub fn is_shutdown(&self) -> bool {
2907                 if (self.channel_state & ChannelState::ShutdownComplete as u32) == ChannelState::ShutdownComplete as u32  {
2908                         assert!(self.channel_state == ChannelState::ShutdownComplete as u32);
2909                         true
2910                 } else { false }
2911         }
2912
2913         /// Called by channelmanager based on chain blocks being connected.
2914         /// Note that we only need to use this to detect funding_signed, anything else is handled by
2915         /// the channel_monitor.
2916         /// In case of Err, the channel may have been closed, at which point the standard requirements
2917         /// apply - no calls may be made except those explicitly stated to be allowed post-shutdown.
2918         /// Only returns an ErrorAction of DisconnectPeer, if Err.
2919         pub fn block_connected(&mut self, header: &BlockHeader, height: u32, txn_matched: &[&Transaction], indexes_of_txn_matched: &[u32]) -> Result<Option<msgs::FundingLocked>, msgs::ErrorMessage> {
2920                 let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
2921                 if header.bitcoin_hash() != self.last_block_connected {
2922                         self.last_block_connected = header.bitcoin_hash();
2923                         self.channel_monitor.last_block_hash = self.last_block_connected;
2924                         if self.funding_tx_confirmations > 0 {
2925                                 self.funding_tx_confirmations += 1;
2926                                 if self.funding_tx_confirmations == self.minimum_depth as u64 {
2927                                         let need_commitment_update = if non_shutdown_state == ChannelState::FundingSent as u32 {
2928                                                 self.channel_state |= ChannelState::OurFundingLocked as u32;
2929                                                 true
2930                                         } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::TheirFundingLocked as u32) {
2931                                                 self.channel_state = ChannelState::ChannelFunded as u32 | (self.channel_state & MULTI_STATE_FLAGS);
2932                                                 self.channel_update_count += 1;
2933                                                 true
2934                                         } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::OurFundingLocked as u32) {
2935                                                 // We got a reorg but not enough to trigger a force close, just update
2936                                                 // funding_tx_confirmed_in and return.
2937                                                 false
2938                                         } else if self.channel_state < ChannelState::ChannelFunded as u32 {
2939                                                 panic!("Started confirming a channel in a state pre-FundingSent?: {}", self.channel_state);
2940                                         } else {
2941                                                 // We got a reorg but not enough to trigger a force close, just update
2942                                                 // funding_tx_confirmed_in and return.
2943                                                 false
2944                                         };
2945                                         self.funding_tx_confirmed_in = Some(header.bitcoin_hash());
2946
2947                                         //TODO: Note that this must be a duplicate of the previous commitment point they sent us,
2948                                         //as otherwise we will have a commitment transaction that they can't revoke (well, kinda,
2949                                         //they can by sending two revoke_and_acks back-to-back, but not really). This appears to be
2950                                         //a protocol oversight, but I assume I'm just missing something.
2951                                         if need_commitment_update {
2952                                                 let next_per_commitment_secret = self.build_local_commitment_secret(self.cur_local_commitment_transaction_number);
2953                                                 let next_per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &next_per_commitment_secret);
2954                                                 return Ok(Some(msgs::FundingLocked {
2955                                                         channel_id: self.channel_id,
2956                                                         next_per_commitment_point: next_per_commitment_point,
2957                                                 }));
2958                                         }
2959                                 }
2960                         }
2961                 }
2962                 if non_shutdown_state & !(ChannelState::TheirFundingLocked as u32) == ChannelState::FundingSent as u32 {
2963                         for (ref tx, index_in_block) in txn_matched.iter().zip(indexes_of_txn_matched) {
2964                                 if tx.txid() == self.channel_monitor.get_funding_txo().unwrap().txid {
2965                                         let txo_idx = self.channel_monitor.get_funding_txo().unwrap().index as usize;
2966                                         if txo_idx >= tx.output.len() || tx.output[txo_idx].script_pubkey != self.get_funding_redeemscript().to_v0_p2wsh() ||
2967                                                         tx.output[txo_idx].value != self.channel_value_satoshis {
2968                                                 if self.channel_outbound {
2969                                                         // If we generated the funding transaction and it doesn't match what it
2970                                                         // should, the client is really broken and we should just panic and
2971                                                         // tell them off. That said, because hash collisions happen with high
2972                                                         // probability in fuzztarget mode, if we're fuzzing we just close the
2973                                                         // channel and move on.
2974                                                         #[cfg(not(feature = "fuzztarget"))]
2975                                                         panic!("Client called ChannelManager::funding_transaction_generated with bogus transaction!");
2976                                                 }
2977                                                 self.channel_state = ChannelState::ShutdownComplete as u32;
2978                                                 self.channel_update_count += 1;
2979                                                 return Err(msgs::ErrorMessage {
2980                                                         channel_id: self.channel_id(),
2981                                                         data: "funding tx had wrong script/value".to_owned()
2982                                                 });
2983                                         } else {
2984                                                 if self.channel_outbound {
2985                                                         for input in tx.input.iter() {
2986                                                                 if input.witness.is_empty() {
2987                                                                         // We generated a malleable funding transaction, implying we've
2988                                                                         // just exposed ourselves to funds loss to our counterparty.
2989                                                                         #[cfg(not(feature = "fuzztarget"))]
2990                                                                         panic!("Client called ChannelManager::funding_transaction_generated with bogus transaction!");
2991                                                                 }
2992                                                         }
2993                                                 }
2994                                                 self.funding_tx_confirmations = 1;
2995                                                 self.short_channel_id = Some(((height as u64)          << (5*8)) |
2996                                                                              ((*index_in_block as u64) << (2*8)) |
2997                                                                              ((txo_idx as u64)         << (0*8)));
2998                                         }
2999                                 }
3000                         }
3001                 }
3002                 Ok(None)
3003         }
3004
3005         /// Called by channelmanager based on chain blocks being disconnected.
3006         /// Returns true if we need to close the channel now due to funding transaction
3007         /// unconfirmation/reorg.
3008         pub fn block_disconnected(&mut self, header: &BlockHeader) -> bool {
3009                 if self.funding_tx_confirmations > 0 {
3010                         self.funding_tx_confirmations -= 1;
3011                         if self.funding_tx_confirmations == UNCONF_THRESHOLD as u64 {
3012                                 return true;
3013                         }
3014                 }
3015                 if Some(header.bitcoin_hash()) == self.funding_tx_confirmed_in {
3016                         self.funding_tx_confirmations = self.minimum_depth as u64 - 1;
3017                 }
3018                 self.last_block_connected = header.bitcoin_hash();
3019                 self.channel_monitor.last_block_hash = self.last_block_connected;
3020                 false
3021         }
3022
3023         // Methods to get unprompted messages to send to the remote end (or where we already returned
3024         // something in the handler for the message that prompted this message):
3025
3026         pub fn get_open_channel(&self, chain_hash: Sha256dHash, fee_estimator: &FeeEstimator) -> msgs::OpenChannel {
3027                 if !self.channel_outbound {
3028                         panic!("Tried to open a channel for an inbound channel?");
3029                 }
3030                 if self.channel_state != ChannelState::OurInitSent as u32 {
3031                         panic!("Cannot generate an open_channel after we've moved forward");
3032                 }
3033
3034                 if self.cur_local_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
3035                         panic!("Tried to send an open_channel for a channel that has already advanced");
3036                 }
3037
3038                 let local_commitment_secret = self.build_local_commitment_secret(self.cur_local_commitment_transaction_number);
3039
3040                 msgs::OpenChannel {
3041                         chain_hash: chain_hash,
3042                         temporary_channel_id: self.channel_id,
3043                         funding_satoshis: self.channel_value_satoshis,
3044                         push_msat: self.channel_value_satoshis * 1000 - self.value_to_self_msat,
3045                         dust_limit_satoshis: self.our_dust_limit_satoshis,
3046                         max_htlc_value_in_flight_msat: Channel::get_our_max_htlc_value_in_flight_msat(self.channel_value_satoshis),
3047                         channel_reserve_satoshis: Channel::get_our_channel_reserve_satoshis(self.channel_value_satoshis),
3048                         htlc_minimum_msat: self.our_htlc_minimum_msat,
3049                         feerate_per_kw: fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background) as u32,
3050                         to_self_delay: BREAKDOWN_TIMEOUT,
3051                         max_accepted_htlcs: OUR_MAX_HTLCS,
3052                         funding_pubkey: PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.funding_key),
3053                         revocation_basepoint: PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.revocation_base_key),
3054                         payment_basepoint: PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.payment_base_key),
3055                         delayed_payment_basepoint: PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.delayed_payment_base_key),
3056                         htlc_basepoint: PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.htlc_base_key),
3057                         first_per_commitment_point: PublicKey::from_secret_key(&self.secp_ctx, &local_commitment_secret),
3058                         channel_flags: if self.config.announced_channel {1} else {0},
3059                         shutdown_scriptpubkey: OptionalField::Absent
3060                 }
3061         }
3062
3063         pub fn get_accept_channel(&self) -> msgs::AcceptChannel {
3064                 if self.channel_outbound {
3065                         panic!("Tried to send accept_channel for an outbound channel?");
3066                 }
3067                 if self.channel_state != (ChannelState::OurInitSent as u32) | (ChannelState::TheirInitSent as u32) {
3068                         panic!("Tried to send accept_channel after channel had moved forward");
3069                 }
3070                 if self.cur_local_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
3071                         panic!("Tried to send an accept_channel for a channel that has already advanced");
3072                 }
3073
3074                 let local_commitment_secret = self.build_local_commitment_secret(self.cur_local_commitment_transaction_number);
3075
3076                 msgs::AcceptChannel {
3077                         temporary_channel_id: self.channel_id,
3078                         dust_limit_satoshis: self.our_dust_limit_satoshis,
3079                         max_htlc_value_in_flight_msat: Channel::get_our_max_htlc_value_in_flight_msat(self.channel_value_satoshis),
3080                         channel_reserve_satoshis: Channel::get_our_channel_reserve_satoshis(self.channel_value_satoshis),
3081                         htlc_minimum_msat: self.our_htlc_minimum_msat,
3082                         minimum_depth: self.minimum_depth,
3083                         to_self_delay: BREAKDOWN_TIMEOUT,
3084                         max_accepted_htlcs: OUR_MAX_HTLCS,
3085                         funding_pubkey: PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.funding_key),
3086                         revocation_basepoint: PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.revocation_base_key),
3087                         payment_basepoint: PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.payment_base_key),
3088                         delayed_payment_basepoint: PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.delayed_payment_base_key),
3089                         htlc_basepoint: PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.htlc_base_key),
3090                         first_per_commitment_point: PublicKey::from_secret_key(&self.secp_ctx, &local_commitment_secret),
3091                         shutdown_scriptpubkey: OptionalField::Absent
3092                 }
3093         }
3094
3095         /// If an Err is returned, it is a ChannelError::Close (for get_outbound_funding_created)
3096         fn get_outbound_funding_created_signature(&mut self) -> Result<(Signature, Transaction), ChannelError> {
3097                 let funding_script = self.get_funding_redeemscript();
3098
3099                 let remote_keys = self.build_remote_transaction_keys()?;
3100                 let remote_initial_commitment_tx = self.build_commitment_transaction(self.cur_remote_commitment_transaction_number, &remote_keys, false, false, self.feerate_per_kw).0;
3101                 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)[..]);
3102
3103                 // We sign the "remote" commitment transaction, allowing them to broadcast the tx if they wish.
3104                 Ok((self.secp_ctx.sign(&remote_sighash, &self.local_keys.funding_key), remote_initial_commitment_tx))
3105         }
3106
3107         /// Updates channel state with knowledge of the funding transaction's txid/index, and generates
3108         /// a funding_created message for the remote peer.
3109         /// Panics if called at some time other than immediately after initial handshake, if called twice,
3110         /// or if called on an inbound channel.
3111         /// Note that channel_id changes during this call!
3112         /// Do NOT broadcast the funding transaction until after a successful funding_signed call!
3113         /// If an Err is returned, it is a ChannelError::Close.
3114         pub fn get_outbound_funding_created(&mut self, funding_txo: OutPoint) -> Result<(msgs::FundingCreated, ChannelMonitor), ChannelError> {
3115                 if !self.channel_outbound {
3116                         panic!("Tried to create outbound funding_created message on an inbound channel!");
3117                 }
3118                 if self.channel_state != (ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32) {
3119                         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)");
3120                 }
3121                 if self.channel_monitor.get_min_seen_secret() != (1 << 48) ||
3122                                 self.cur_remote_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER ||
3123                                 self.cur_local_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
3124                         panic!("Should not have advanced channel commitment tx numbers prior to funding_created");
3125                 }
3126
3127                 let funding_txo_script = self.get_funding_redeemscript().to_v0_p2wsh();
3128                 self.channel_monitor.set_funding_info((funding_txo, funding_txo_script));
3129
3130                 let (our_signature, commitment_tx) = match self.get_outbound_funding_created_signature() {
3131                         Ok(res) => res,
3132                         Err(e) => {
3133                                 log_error!(self, "Got bad signatures: {:?}!", e);
3134                                 self.channel_monitor.unset_funding_info();
3135                                 return Err(e);
3136                         }
3137                 };
3138
3139                 let temporary_channel_id = self.channel_id;
3140
3141                 // Now that we're past error-generating stuff, update our local state:
3142                 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());
3143                 self.channel_state = ChannelState::FundingCreated as u32;
3144                 self.channel_id = funding_txo.to_channel_id();
3145                 self.cur_remote_commitment_transaction_number -= 1;
3146
3147                 Ok((msgs::FundingCreated {
3148                         temporary_channel_id: temporary_channel_id,
3149                         funding_txid: funding_txo.txid,
3150                         funding_output_index: funding_txo.index,
3151                         signature: our_signature
3152                 }, self.channel_monitor.clone()))
3153         }
3154
3155         /// Gets an UnsignedChannelAnnouncement, as well as a signature covering it using our
3156         /// bitcoin_key, if available, for this channel. The channel must be publicly announceable and
3157         /// available for use (have exchanged FundingLocked messages in both directions). Should be used
3158         /// for both loose and in response to an AnnouncementSignatures message from the remote peer.
3159         /// Will only fail if we're not in a state where channel_announcement may be sent (including
3160         /// closing).
3161         /// Note that the "channel must be funded" requirement is stricter than BOLT 7 requires - see
3162         /// https://github.com/lightningnetwork/lightning-rfc/issues/468
3163         pub fn get_channel_announcement(&self, our_node_id: PublicKey, chain_hash: Sha256dHash) -> Result<(msgs::UnsignedChannelAnnouncement, Signature), ChannelError> {
3164                 if !self.config.announced_channel {
3165                         return Err(ChannelError::Ignore("Channel is not available for public announcements"));
3166                 }
3167                 if self.channel_state & (ChannelState::ChannelFunded as u32) == 0 {
3168                         return Err(ChannelError::Ignore("Cannot get a ChannelAnnouncement until the channel funding has been locked"));
3169                 }
3170                 if (self.channel_state & (ChannelState::LocalShutdownSent as u32 | ChannelState::ShutdownComplete as u32)) != 0 {
3171                         return Err(ChannelError::Ignore("Cannot get a ChannelAnnouncement once the channel is closing"));
3172                 }
3173
3174                 let were_node_one = our_node_id.serialize()[..] < self.their_node_id.serialize()[..];
3175                 let our_bitcoin_key = PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.funding_key);
3176
3177                 let msg = msgs::UnsignedChannelAnnouncement {
3178                         features: msgs::GlobalFeatures::new(),
3179                         chain_hash: chain_hash,
3180                         short_channel_id: self.get_short_channel_id().unwrap(),
3181                         node_id_1: if were_node_one { our_node_id } else { self.get_their_node_id() },
3182                         node_id_2: if were_node_one { self.get_their_node_id() } else { our_node_id },
3183                         bitcoin_key_1: if were_node_one { our_bitcoin_key } else { self.their_funding_pubkey.unwrap() },
3184                         bitcoin_key_2: if were_node_one { self.their_funding_pubkey.unwrap() } else { our_bitcoin_key },
3185                         excess_data: Vec::new(),
3186                 };
3187
3188                 let msghash = hash_to_message!(&Sha256dHash::hash(&msg.encode()[..])[..]);
3189                 let sig = self.secp_ctx.sign(&msghash, &self.local_keys.funding_key);
3190
3191                 Ok((msg, sig))
3192         }
3193
3194         /// May panic if called on a channel that wasn't immediately-previously
3195         /// self.remove_uncommitted_htlcs_and_mark_paused()'d
3196         pub fn get_channel_reestablish(&self) -> msgs::ChannelReestablish {
3197                 assert_eq!(self.channel_state & ChannelState::PeerDisconnected as u32, ChannelState::PeerDisconnected as u32);
3198                 assert_ne!(self.cur_remote_commitment_transaction_number, INITIAL_COMMITMENT_NUMBER);
3199                 msgs::ChannelReestablish {
3200                         channel_id: self.channel_id(),
3201                         // The protocol has two different commitment number concepts - the "commitment
3202                         // transaction number", which starts from 0 and counts up, and the "revocation key
3203                         // index" which starts at INITIAL_COMMITMENT_NUMBER and counts down. We track
3204                         // commitment transaction numbers by the index which will be used to reveal the
3205                         // revocation key for that commitment transaction, which means we have to convert them
3206                         // to protocol-level commitment numbers here...
3207
3208                         // next_local_commitment_number is the next commitment_signed number we expect to
3209                         // receive (indicating if they need to resend one that we missed).
3210                         next_local_commitment_number: INITIAL_COMMITMENT_NUMBER - self.cur_local_commitment_transaction_number,
3211                         // We have to set next_remote_commitment_number to the next revoke_and_ack we expect to
3212                         // receive, however we track it by the next commitment number for a remote transaction
3213                         // (which is one further, as they always revoke previous commitment transaction, not
3214                         // the one we send) so we have to decrement by 1. Note that if
3215                         // cur_remote_commitment_transaction_number is INITIAL_COMMITMENT_NUMBER we will have
3216                         // dropped this channel on disconnect as it hasn't yet reached FundingSent so we can't
3217                         // overflow here.
3218                         next_remote_commitment_number: INITIAL_COMMITMENT_NUMBER - self.cur_remote_commitment_transaction_number - 1,
3219                         data_loss_protect: OptionalField::Absent,
3220                 }
3221         }
3222
3223
3224         // Send stuff to our remote peers:
3225
3226         /// Adds a pending outbound HTLC to this channel, note that you probably want
3227         /// send_htlc_and_commit instead cause you'll want both messages at once.
3228         /// This returns an option instead of a pure UpdateAddHTLC as we may be in a state where we are
3229         /// waiting on the remote peer to send us a revoke_and_ack during which time we cannot add new
3230         /// HTLCs on the wire or we wouldn't be able to determine what they actually ACK'ed.
3231         /// You MUST call send_commitment prior to any other calls on this Channel
3232         /// If an Err is returned, it's a ChannelError::Ignore!
3233         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> {
3234                 if (self.channel_state & (ChannelState::ChannelFunded as u32 | BOTH_SIDES_SHUTDOWN_MASK)) != (ChannelState::ChannelFunded as u32) {
3235                         return Err(ChannelError::Ignore("Cannot send HTLC until channel is fully established and we haven't started shutting down"));
3236                 }
3237
3238                 if amount_msat > self.channel_value_satoshis * 1000 {
3239                         return Err(ChannelError::Ignore("Cannot send more than the total value of the channel"));
3240                 }
3241                 if amount_msat < self.their_htlc_minimum_msat {
3242                         return Err(ChannelError::Ignore("Cannot send less than their minimum HTLC value"));
3243                 }
3244
3245                 if (self.channel_state & (ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32)) != 0 {
3246                         // Note that this should never really happen, if we're !is_live() on receipt of an
3247                         // incoming HTLC for relay will result in us rejecting the HTLC and we won't allow
3248                         // the user to send directly into a !is_live() channel. However, if we
3249                         // disconnected during the time the previous hop was doing the commitment dance we may
3250                         // end up getting here after the forwarding delay. In any case, returning an
3251                         // IgnoreError will get ChannelManager to do the right thing and fail backwards now.
3252                         return Err(ChannelError::Ignore("Cannot send an HTLC while disconnected/frozen for channel monitor update"));
3253                 }
3254
3255                 let (outbound_htlc_count, htlc_outbound_value_msat) = self.get_outbound_pending_htlc_stats();
3256                 if outbound_htlc_count + 1 > self.their_max_accepted_htlcs as u32 {
3257                         return Err(ChannelError::Ignore("Cannot push more than their max accepted HTLCs"));
3258                 }
3259                 //TODO: Spec is unclear if this is per-direction or in total (I assume per direction):
3260                 // Check their_max_htlc_value_in_flight_msat
3261                 if htlc_outbound_value_msat + amount_msat > self.their_max_htlc_value_in_flight_msat {
3262                         return Err(ChannelError::Ignore("Cannot send value that would put us over the max HTLC value in flight"));
3263                 }
3264
3265                 // Check self.their_channel_reserve_satoshis (the amount we must keep as
3266                 // reserve for them to have something to claim if we misbehave)
3267                 if self.value_to_self_msat < self.their_channel_reserve_satoshis * 1000 + amount_msat + htlc_outbound_value_msat {
3268                         return Err(ChannelError::Ignore("Cannot send value that would put us over the reserve value"));
3269                 }
3270
3271                 //TODO: Check cltv_expiry? Do this in channel manager?
3272
3273                 // Now update local state:
3274                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == (ChannelState::AwaitingRemoteRevoke as u32) {
3275                         self.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::AddHTLC {
3276                                 amount_msat: amount_msat,
3277                                 payment_hash: payment_hash,
3278                                 cltv_expiry: cltv_expiry,
3279                                 source,
3280                                 onion_routing_packet: onion_routing_packet,
3281                                 time_created: Instant::now(),
3282                         });
3283                         return Ok(None);
3284                 }
3285
3286                 self.pending_outbound_htlcs.push(OutboundHTLCOutput {
3287                         htlc_id: self.next_local_htlc_id,
3288                         amount_msat: amount_msat,
3289                         payment_hash: payment_hash.clone(),
3290                         cltv_expiry: cltv_expiry,
3291                         state: OutboundHTLCState::LocalAnnounced(Box::new(onion_routing_packet.clone())),
3292                         source,
3293                 });
3294
3295                 let res = msgs::UpdateAddHTLC {
3296                         channel_id: self.channel_id,
3297                         htlc_id: self.next_local_htlc_id,
3298                         amount_msat: amount_msat,
3299                         payment_hash: payment_hash,
3300                         cltv_expiry: cltv_expiry,
3301                         onion_routing_packet: onion_routing_packet,
3302                 };
3303                 self.next_local_htlc_id += 1;
3304
3305                 Ok(Some(res))
3306         }
3307
3308         /// Creates a signed commitment transaction to send to the remote peer.
3309         /// Always returns a ChannelError::Close if an immediately-preceding (read: the
3310         /// last call to this Channel) send_htlc returned Ok(Some(_)) and there is an Err.
3311         /// May panic if called except immediately after a successful, Ok(Some(_))-returning send_htlc.
3312         pub fn send_commitment(&mut self) -> Result<(msgs::CommitmentSigned, ChannelMonitor), ChannelError> {
3313                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
3314                         panic!("Cannot create commitment tx until channel is fully established");
3315                 }
3316                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == (ChannelState::AwaitingRemoteRevoke as u32) {
3317                         panic!("Cannot create commitment tx until remote revokes their previous commitment");
3318                 }
3319                 if (self.channel_state & (ChannelState::PeerDisconnected as u32)) == (ChannelState::PeerDisconnected as u32) {
3320                         panic!("Cannot create commitment tx while disconnected, as send_htlc will have returned an Err so a send_commitment precondition has been violated");
3321                 }
3322                 if (self.channel_state & (ChannelState::MonitorUpdateFailed as u32)) == (ChannelState::MonitorUpdateFailed as u32) {
3323                         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");
3324                 }
3325                 let mut have_updates = self.pending_update_fee.is_some();
3326                 for htlc in self.pending_outbound_htlcs.iter() {
3327                         if let OutboundHTLCState::LocalAnnounced(_) = htlc.state {
3328                                 have_updates = true;
3329                         }
3330                         if have_updates { break; }
3331                 }
3332                 for htlc in self.pending_inbound_htlcs.iter() {
3333                         if let InboundHTLCState::LocalRemoved(_) = htlc.state {
3334                                 have_updates = true;
3335                         }
3336                         if have_updates { break; }
3337                 }
3338                 if !have_updates {
3339                         panic!("Cannot create commitment tx until we have some updates to send");
3340                 }
3341                 self.send_commitment_no_status_check()
3342         }
3343         /// Only fails in case of bad keys
3344         fn send_commitment_no_status_check(&mut self) -> Result<(msgs::CommitmentSigned, ChannelMonitor), ChannelError> {
3345                 // We can upgrade the status of some HTLCs that are waiting on a commitment, even if we
3346                 // fail to generate this, we still are at least at a position where upgrading their status
3347                 // is acceptable.
3348                 for htlc in self.pending_inbound_htlcs.iter_mut() {
3349                         let new_state = if let &InboundHTLCState::AwaitingRemoteRevokeToAnnounce(ref forward_info) = &htlc.state {
3350                                 Some(InboundHTLCState::AwaitingAnnouncedRemoteRevoke(forward_info.clone()))
3351                         } else { None };
3352                         if let Some(state) = new_state {
3353                                 htlc.state = state;
3354                         }
3355                 }
3356                 for htlc in self.pending_outbound_htlcs.iter_mut() {
3357                         if let Some(fail_reason) = if let &mut OutboundHTLCState::AwaitingRemoteRevokeToRemove(ref mut fail_reason) = &mut htlc.state {
3358                                 Some(fail_reason.take())
3359                         } else { None } {
3360                                 htlc.state = OutboundHTLCState::AwaitingRemovedRemoteRevoke(fail_reason);
3361                         }
3362                 }
3363
3364                 let (res, remote_commitment_tx, htlcs) = match self.send_commitment_no_state_update() {
3365                         Ok((res, (remote_commitment_tx, mut htlcs))) => {
3366                                 // Update state now that we've passed all the can-fail calls...
3367                                 let htlcs_no_ref = htlcs.drain(..).map(|(htlc, htlc_source)| (htlc, htlc_source.map(|source_ref| Box::new(source_ref.clone())))).collect();
3368                                 (res, remote_commitment_tx, htlcs_no_ref)
3369                         },
3370                         Err(e) => return Err(e),
3371                 };
3372
3373                 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());
3374                 self.channel_state |= ChannelState::AwaitingRemoteRevoke as u32;
3375                 Ok((res, self.channel_monitor.clone()))
3376         }
3377
3378         /// Only fails in case of bad keys. Used for channel_reestablish commitment_signed generation
3379         /// when we shouldn't change HTLC/channel state.
3380         fn send_commitment_no_state_update(&self) -> Result<(msgs::CommitmentSigned, (Transaction, Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)>)), ChannelError> {
3381                 let funding_script = self.get_funding_redeemscript();
3382
3383                 let mut feerate_per_kw = self.feerate_per_kw;
3384                 if let Some(feerate) = self.pending_update_fee {
3385                         if self.channel_outbound {
3386                                 feerate_per_kw = feerate;
3387                         }
3388                 }
3389
3390                 let remote_keys = self.build_remote_transaction_keys()?;
3391                 let remote_commitment_tx = self.build_commitment_transaction(self.cur_remote_commitment_transaction_number, &remote_keys, false, true, feerate_per_kw);
3392                 let remote_commitment_txid = remote_commitment_tx.0.txid();
3393                 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)[..]);
3394                 let our_sig = self.secp_ctx.sign(&remote_sighash, &self.local_keys.funding_key);
3395                 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()[..]));
3396
3397                 let mut htlc_sigs = Vec::with_capacity(remote_commitment_tx.1);
3398                 for &(ref htlc, _) in remote_commitment_tx.2.iter() {
3399                         if let Some(_) = htlc.transaction_output_index {
3400                                 let htlc_tx = self.build_htlc_transaction(&remote_commitment_txid, htlc, false, &remote_keys, feerate_per_kw);
3401                                 let htlc_redeemscript = chan_utils::get_htlc_redeemscript(&htlc, &remote_keys);
3402                                 let htlc_sighash = hash_to_message!(&bip143::SighashComponents::new(&htlc_tx).sighash_all(&htlc_tx.input[0], &htlc_redeemscript, htlc.amount_msat / 1000)[..]);
3403                                 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");
3404                                 htlc_sigs.push(self.secp_ctx.sign(&htlc_sighash, &our_htlc_key));
3405                                 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()[..]));
3406                         }
3407                 }
3408
3409                 Ok((msgs::CommitmentSigned {
3410                         channel_id: self.channel_id,
3411                         signature: our_sig,
3412                         htlc_signatures: htlc_sigs,
3413                 }, (remote_commitment_tx.0, remote_commitment_tx.2)))
3414         }
3415
3416         /// Adds a pending outbound HTLC to this channel, and creates a signed commitment transaction
3417         /// to send to the remote peer in one go.
3418         /// Shorthand for calling send_htlc() followed by send_commitment(), see docs on those for
3419         /// more info.
3420         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> {
3421                 match self.send_htlc(amount_msat, payment_hash, cltv_expiry, source, onion_routing_packet)? {
3422                         Some(update_add_htlc) => {
3423                                 let (commitment_signed, monitor_update) = self.send_commitment_no_status_check()?;
3424                                 Ok(Some((update_add_htlc, commitment_signed, monitor_update)))
3425                         },
3426                         None => Ok(None)
3427                 }
3428         }
3429
3430         /// Begins the shutdown process, getting a message for the remote peer and returning all
3431         /// holding cell HTLCs for payment failure.
3432         pub fn get_shutdown(&mut self) -> Result<(msgs::Shutdown, Vec<(HTLCSource, PaymentHash)>), APIError> {
3433                 for htlc in self.pending_outbound_htlcs.iter() {
3434                         if let OutboundHTLCState::LocalAnnounced(_) = htlc.state {
3435                                 return Err(APIError::APIMisuseError{err: "Cannot begin shutdown with pending HTLCs. Process pending events first"});
3436                         }
3437                 }
3438                 if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK != 0 {
3439                         if (self.channel_state & ChannelState::LocalShutdownSent as u32) == ChannelState::LocalShutdownSent as u32 {
3440                                 return Err(APIError::APIMisuseError{err: "Shutdown already in progress"});
3441                         }
3442                         else if (self.channel_state & ChannelState::RemoteShutdownSent as u32) == ChannelState::RemoteShutdownSent as u32 {
3443                                 return Err(APIError::ChannelUnavailable{err: "Shutdown already in progress by remote"});
3444                         }
3445                 }
3446                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
3447                 if self.channel_state & (ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32) != 0 {
3448                         return Err(APIError::ChannelUnavailable{err: "Cannot begin shutdown while peer is disconnected or we're waiting on a monitor update, maybe force-close instead?"});
3449                 }
3450
3451                 let our_closing_script = self.get_closing_scriptpubkey();
3452
3453                 // From here on out, we may not fail!
3454                 if self.channel_state < ChannelState::FundingSent as u32 {
3455                         self.channel_state = ChannelState::ShutdownComplete as u32;
3456                 } else {
3457                         self.channel_state |= ChannelState::LocalShutdownSent as u32;
3458                 }
3459                 self.channel_update_count += 1;
3460
3461                 // Go ahead and drop holding cell updates as we'd rather fail payments than wait to send
3462                 // our shutdown until we've committed all of the pending changes.
3463                 self.holding_cell_update_fee = None;
3464                 let mut dropped_outbound_htlcs = Vec::with_capacity(self.holding_cell_htlc_updates.len());
3465                 self.holding_cell_htlc_updates.retain(|htlc_update| {
3466                         match htlc_update {
3467                                 &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, ref source, .. } => {
3468                                         dropped_outbound_htlcs.push((source.clone(), payment_hash.clone()));
3469                                         false
3470                                 },
3471                                 _ => true
3472                         }
3473                 });
3474
3475                 Ok((msgs::Shutdown {
3476                         channel_id: self.channel_id,
3477                         scriptpubkey: our_closing_script,
3478                 }, dropped_outbound_htlcs))
3479         }
3480
3481         /// Gets the latest commitment transaction and any dependent transactions for relay (forcing
3482         /// shutdown of this channel - no more calls into this Channel may be made afterwards except
3483         /// those explicitly stated to be allowed after shutdown completes, eg some simple getters).
3484         /// Also returns the list of payment_hashes for channels which we can safely fail backwards
3485         /// immediately (others we will have to allow to time out).
3486         pub fn force_shutdown(&mut self) -> (Vec<Transaction>, Vec<(HTLCSource, PaymentHash)>) {
3487                 assert!(self.channel_state != ChannelState::ShutdownComplete as u32);
3488
3489                 // We go ahead and "free" any holding cell HTLCs or HTLCs we haven't yet committed to and
3490                 // return them to fail the payment.
3491                 let mut dropped_outbound_htlcs = Vec::with_capacity(self.holding_cell_htlc_updates.len());
3492                 for htlc_update in self.holding_cell_htlc_updates.drain(..) {
3493                         match htlc_update {
3494                                 HTLCUpdateAwaitingACK::AddHTLC { source, payment_hash, .. } => {
3495                                         dropped_outbound_htlcs.push((source, payment_hash));
3496                                 },
3497                                 _ => {}
3498                         }
3499                 }
3500
3501                 for _htlc in self.pending_outbound_htlcs.drain(..) {
3502                         //TODO: Do something with the remaining HTLCs
3503                         //(we need to have the ChannelManager monitor them so we can claim the inbound HTLCs
3504                         //which correspond)
3505                 }
3506
3507                 self.channel_state = ChannelState::ShutdownComplete as u32;
3508                 self.channel_update_count += 1;
3509                 let mut res = Vec::new();
3510                 mem::swap(&mut res, &mut self.last_local_commitment_txn);
3511                 (res, dropped_outbound_htlcs)
3512         }
3513 }
3514
3515 const SERIALIZATION_VERSION: u8 = 1;
3516 const MIN_SERIALIZATION_VERSION: u8 = 1;
3517
3518 impl Writeable for InboundHTLCRemovalReason {
3519         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3520                 match self {
3521                         &InboundHTLCRemovalReason::FailRelay(ref error_packet) => {
3522                                 0u8.write(writer)?;
3523                                 error_packet.write(writer)?;
3524                         },
3525                         &InboundHTLCRemovalReason::FailMalformed((ref onion_hash, ref err_code)) => {
3526                                 1u8.write(writer)?;
3527                                 onion_hash.write(writer)?;
3528                                 err_code.write(writer)?;
3529                         },
3530                         &InboundHTLCRemovalReason::Fulfill(ref payment_preimage) => {
3531                                 2u8.write(writer)?;
3532                                 payment_preimage.write(writer)?;
3533                         },
3534                 }
3535                 Ok(())
3536         }
3537 }
3538
3539 impl<R: ::std::io::Read> Readable<R> for InboundHTLCRemovalReason {
3540         fn read(reader: &mut R) -> Result<Self, DecodeError> {
3541                 Ok(match <u8 as Readable<R>>::read(reader)? {
3542                         0 => InboundHTLCRemovalReason::FailRelay(Readable::read(reader)?),
3543                         1 => InboundHTLCRemovalReason::FailMalformed((Readable::read(reader)?, Readable::read(reader)?)),
3544                         2 => InboundHTLCRemovalReason::Fulfill(Readable::read(reader)?),
3545                         _ => return Err(DecodeError::InvalidValue),
3546                 })
3547         }
3548 }
3549
3550 impl Writeable for Channel {
3551         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3552                 // Note that we write out as if remove_uncommitted_htlcs_and_mark_paused had just been
3553                 // called but include holding cell updates (and obviously we don't modify self).
3554
3555                 writer.write_all(&[SERIALIZATION_VERSION; 1])?;
3556                 writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
3557
3558                 self.user_id.write(writer)?;
3559                 self.config.write(writer)?;
3560
3561                 self.channel_id.write(writer)?;
3562                 (self.channel_state | ChannelState::PeerDisconnected as u32).write(writer)?;
3563                 self.channel_outbound.write(writer)?;
3564                 self.channel_value_satoshis.write(writer)?;
3565
3566                 self.local_keys.write(writer)?;
3567                 self.shutdown_pubkey.write(writer)?;
3568
3569                 self.cur_local_commitment_transaction_number.write(writer)?;
3570                 self.cur_remote_commitment_transaction_number.write(writer)?;
3571                 self.value_to_self_msat.write(writer)?;
3572
3573                 self.received_commitment_while_awaiting_raa.write(writer)?;
3574
3575                 let mut dropped_inbound_htlcs = 0;
3576                 for htlc in self.pending_inbound_htlcs.iter() {
3577                         if let InboundHTLCState::RemoteAnnounced(_) = htlc.state {
3578                                 dropped_inbound_htlcs += 1;
3579                         }
3580                 }
3581                 (self.pending_inbound_htlcs.len() as u64 - dropped_inbound_htlcs).write(writer)?;
3582                 for htlc in self.pending_inbound_htlcs.iter() {
3583                         htlc.htlc_id.write(writer)?;
3584                         htlc.amount_msat.write(writer)?;
3585                         htlc.cltv_expiry.write(writer)?;
3586                         htlc.payment_hash.write(writer)?;
3587                         match &htlc.state {
3588                                 &InboundHTLCState::RemoteAnnounced(_) => {}, // Drop
3589                                 &InboundHTLCState::AwaitingRemoteRevokeToAnnounce(ref htlc_state) => {
3590                                         1u8.write(writer)?;
3591                                         htlc_state.write(writer)?;
3592                                 },
3593                                 &InboundHTLCState::AwaitingAnnouncedRemoteRevoke(ref htlc_state) => {
3594                                         2u8.write(writer)?;
3595                                         htlc_state.write(writer)?;
3596                                 },
3597                                 &InboundHTLCState::Committed => {
3598                                         3u8.write(writer)?;
3599                                 },
3600                                 &InboundHTLCState::LocalRemoved(ref removal_reason) => {
3601                                         4u8.write(writer)?;
3602                                         removal_reason.write(writer)?;
3603                                 },
3604                         }
3605                 }
3606
3607                 macro_rules! write_option {
3608                         ($thing: expr) => {
3609                                 match &$thing {
3610                                         &None => 0u8.write(writer)?,
3611                                         &Some(ref v) => {
3612                                                 1u8.write(writer)?;
3613                                                 v.write(writer)?;
3614                                         },
3615                                 }
3616                         }
3617                 }
3618
3619                 (self.pending_outbound_htlcs.len() as u64).write(writer)?;
3620                 for htlc in self.pending_outbound_htlcs.iter() {
3621                         htlc.htlc_id.write(writer)?;
3622                         htlc.amount_msat.write(writer)?;
3623                         htlc.cltv_expiry.write(writer)?;
3624                         htlc.payment_hash.write(writer)?;
3625                         htlc.source.write(writer)?;
3626                         match &htlc.state {
3627                                 &OutboundHTLCState::LocalAnnounced(ref onion_packet) => {
3628                                         0u8.write(writer)?;
3629                                         onion_packet.write(writer)?;
3630                                 },
3631                                 &OutboundHTLCState::Committed => {
3632                                         1u8.write(writer)?;
3633                                 },
3634                                 &OutboundHTLCState::RemoteRemoved(ref fail_reason) => {
3635                                         2u8.write(writer)?;
3636                                         write_option!(*fail_reason);
3637                                 },
3638                                 &OutboundHTLCState::AwaitingRemoteRevokeToRemove(ref fail_reason) => {
3639                                         3u8.write(writer)?;
3640                                         write_option!(*fail_reason);
3641                                 },
3642                                 &OutboundHTLCState::AwaitingRemovedRemoteRevoke(ref fail_reason) => {
3643                                         4u8.write(writer)?;
3644                                         write_option!(*fail_reason);
3645                                 },
3646                         }
3647                 }
3648
3649                 (self.holding_cell_htlc_updates.len() as u64).write(writer)?;
3650                 for update in self.holding_cell_htlc_updates.iter() {
3651                         match update {
3652                                 &HTLCUpdateAwaitingACK::AddHTLC { ref amount_msat, ref cltv_expiry, ref payment_hash, ref source, ref onion_routing_packet, time_created: _ } => {
3653                                         0u8.write(writer)?;
3654                                         amount_msat.write(writer)?;
3655                                         cltv_expiry.write(writer)?;
3656                                         payment_hash.write(writer)?;
3657                                         source.write(writer)?;
3658                                         onion_routing_packet.write(writer)?;
3659                                         // time_created is not serialized - we re-init the timeout upon deserialization
3660                                 },
3661                                 &HTLCUpdateAwaitingACK::ClaimHTLC { ref payment_preimage, ref htlc_id } => {
3662                                         1u8.write(writer)?;
3663                                         payment_preimage.write(writer)?;
3664                                         htlc_id.write(writer)?;
3665                                 },
3666                                 &HTLCUpdateAwaitingACK::FailHTLC { ref htlc_id, ref err_packet } => {
3667                                         2u8.write(writer)?;
3668                                         htlc_id.write(writer)?;
3669                                         err_packet.write(writer)?;
3670                                 }
3671                         }
3672                 }
3673
3674                 self.monitor_pending_revoke_and_ack.write(writer)?;
3675                 self.monitor_pending_commitment_signed.write(writer)?;
3676                 match self.monitor_pending_order {
3677                         None => 0u8.write(writer)?,
3678                         Some(RAACommitmentOrder::CommitmentFirst) => 1u8.write(writer)?,
3679                         Some(RAACommitmentOrder::RevokeAndACKFirst) => 2u8.write(writer)?,
3680                 }
3681
3682                 (self.monitor_pending_forwards.len() as u64).write(writer)?;
3683                 for &(ref pending_forward, ref htlc_id) in self.monitor_pending_forwards.iter() {
3684                         pending_forward.write(writer)?;
3685                         htlc_id.write(writer)?;
3686                 }
3687
3688                 (self.monitor_pending_failures.len() as u64).write(writer)?;
3689                 for &(ref htlc_source, ref payment_hash, ref fail_reason) in self.monitor_pending_failures.iter() {
3690                         htlc_source.write(writer)?;
3691                         payment_hash.write(writer)?;
3692                         fail_reason.write(writer)?;
3693                 }
3694
3695                 write_option!(self.pending_update_fee);
3696                 write_option!(self.holding_cell_update_fee);
3697
3698                 self.next_local_htlc_id.write(writer)?;
3699                 (self.next_remote_htlc_id - dropped_inbound_htlcs).write(writer)?;
3700                 self.channel_update_count.write(writer)?;
3701                 self.feerate_per_kw.write(writer)?;
3702
3703                 (self.last_local_commitment_txn.len() as u64).write(writer)?;
3704                 for tx in self.last_local_commitment_txn.iter() {
3705                         if let Err(e) = tx.consensus_encode(&mut WriterWriteAdaptor(writer)) {
3706                                 match e {
3707                                         encode::Error::Io(e) => return Err(e),
3708                                         _ => panic!("last_local_commitment_txn must have been well-formed!"),
3709                                 }
3710                         }
3711                 }
3712
3713                 match self.last_sent_closing_fee {
3714                         Some((feerate, fee)) => {
3715                                 1u8.write(writer)?;
3716                                 feerate.write(writer)?;
3717                                 fee.write(writer)?;
3718                         },
3719                         None => 0u8.write(writer)?,
3720                 }
3721
3722                 write_option!(self.funding_tx_confirmed_in);
3723                 write_option!(self.short_channel_id);
3724
3725                 self.last_block_connected.write(writer)?;
3726                 self.funding_tx_confirmations.write(writer)?;
3727
3728                 self.their_dust_limit_satoshis.write(writer)?;
3729                 self.our_dust_limit_satoshis.write(writer)?;
3730                 self.their_max_htlc_value_in_flight_msat.write(writer)?;
3731                 self.their_channel_reserve_satoshis.write(writer)?;
3732                 self.their_htlc_minimum_msat.write(writer)?;
3733                 self.our_htlc_minimum_msat.write(writer)?;
3734                 self.their_to_self_delay.write(writer)?;
3735                 self.their_max_accepted_htlcs.write(writer)?;
3736                 self.minimum_depth.write(writer)?;
3737
3738                 write_option!(self.their_funding_pubkey);
3739                 write_option!(self.their_revocation_basepoint);
3740                 write_option!(self.their_payment_basepoint);
3741                 write_option!(self.their_delayed_payment_basepoint);
3742                 write_option!(self.their_htlc_basepoint);
3743                 write_option!(self.their_cur_commitment_point);
3744
3745                 write_option!(self.their_prev_commitment_point);
3746                 self.their_node_id.write(writer)?;
3747
3748                 write_option!(self.their_shutdown_scriptpubkey);
3749
3750                 self.channel_monitor.write_for_disk(writer)?;
3751                 Ok(())
3752         }
3753 }
3754
3755 impl<R : ::std::io::Read> ReadableArgs<R, Arc<Logger>> for Channel {
3756         fn read(reader: &mut R, logger: Arc<Logger>) -> Result<Self, DecodeError> {
3757                 let _ver: u8 = Readable::read(reader)?;
3758                 let min_ver: u8 = Readable::read(reader)?;
3759                 if min_ver > SERIALIZATION_VERSION {
3760                         return Err(DecodeError::UnknownVersion);
3761                 }
3762
3763                 let user_id = Readable::read(reader)?;
3764                 let config: ChannelConfig = Readable::read(reader)?;
3765
3766                 let channel_id = Readable::read(reader)?;
3767                 let channel_state = Readable::read(reader)?;
3768                 let channel_outbound = Readable::read(reader)?;
3769                 let channel_value_satoshis = Readable::read(reader)?;
3770
3771                 let local_keys = Readable::read(reader)?;
3772                 let shutdown_pubkey = Readable::read(reader)?;
3773
3774                 let cur_local_commitment_transaction_number = Readable::read(reader)?;
3775                 let cur_remote_commitment_transaction_number = Readable::read(reader)?;
3776                 let value_to_self_msat = Readable::read(reader)?;
3777
3778                 let received_commitment_while_awaiting_raa = Readable::read(reader)?;
3779
3780                 let pending_inbound_htlc_count: u64 = Readable::read(reader)?;
3781                 let mut pending_inbound_htlcs = Vec::with_capacity(cmp::min(pending_inbound_htlc_count as usize, OUR_MAX_HTLCS as usize));
3782                 for _ in 0..pending_inbound_htlc_count {
3783                         pending_inbound_htlcs.push(InboundHTLCOutput {
3784                                 htlc_id: Readable::read(reader)?,
3785                                 amount_msat: Readable::read(reader)?,
3786                                 cltv_expiry: Readable::read(reader)?,
3787                                 payment_hash: Readable::read(reader)?,
3788                                 state: match <u8 as Readable<R>>::read(reader)? {
3789                                         1 => InboundHTLCState::AwaitingRemoteRevokeToAnnounce(Readable::read(reader)?),
3790                                         2 => InboundHTLCState::AwaitingAnnouncedRemoteRevoke(Readable::read(reader)?),
3791                                         3 => InboundHTLCState::Committed,
3792                                         4 => InboundHTLCState::LocalRemoved(Readable::read(reader)?),
3793                                         _ => return Err(DecodeError::InvalidValue),
3794                                 },
3795                         });
3796                 }
3797
3798                 let pending_outbound_htlc_count: u64 = Readable::read(reader)?;
3799                 let mut pending_outbound_htlcs = Vec::with_capacity(cmp::min(pending_outbound_htlc_count as usize, OUR_MAX_HTLCS as usize));
3800                 for _ in 0..pending_outbound_htlc_count {
3801                         pending_outbound_htlcs.push(OutboundHTLCOutput {
3802                                 htlc_id: Readable::read(reader)?,
3803                                 amount_msat: Readable::read(reader)?,
3804                                 cltv_expiry: Readable::read(reader)?,
3805                                 payment_hash: Readable::read(reader)?,
3806                                 source: Readable::read(reader)?,
3807                                 state: match <u8 as Readable<R>>::read(reader)? {
3808                                         0 => OutboundHTLCState::LocalAnnounced(Box::new(Readable::read(reader)?)),
3809                                         1 => OutboundHTLCState::Committed,
3810                                         2 => OutboundHTLCState::RemoteRemoved(Readable::read(reader)?),
3811                                         3 => OutboundHTLCState::AwaitingRemoteRevokeToRemove(Readable::read(reader)?),
3812                                         4 => OutboundHTLCState::AwaitingRemovedRemoteRevoke(Readable::read(reader)?),
3813                                         _ => return Err(DecodeError::InvalidValue),
3814                                 },
3815                         });
3816                 }
3817
3818                 let holding_cell_htlc_update_count: u64 = Readable::read(reader)?;
3819                 let mut holding_cell_htlc_updates = Vec::with_capacity(cmp::min(holding_cell_htlc_update_count as usize, OUR_MAX_HTLCS as usize*2));
3820                 for _ in 0..holding_cell_htlc_update_count {
3821                         holding_cell_htlc_updates.push(match <u8 as Readable<R>>::read(reader)? {
3822                                 0 => HTLCUpdateAwaitingACK::AddHTLC {
3823                                         amount_msat: Readable::read(reader)?,
3824                                         cltv_expiry: Readable::read(reader)?,
3825                                         payment_hash: Readable::read(reader)?,
3826                                         source: Readable::read(reader)?,
3827                                         onion_routing_packet: Readable::read(reader)?,
3828                                         time_created: Instant::now(),
3829                                 },
3830                                 1 => HTLCUpdateAwaitingACK::ClaimHTLC {
3831                                         payment_preimage: Readable::read(reader)?,
3832                                         htlc_id: Readable::read(reader)?,
3833                                 },
3834                                 2 => HTLCUpdateAwaitingACK::FailHTLC {
3835                                         htlc_id: Readable::read(reader)?,
3836                                         err_packet: Readable::read(reader)?,
3837                                 },
3838                                 _ => return Err(DecodeError::InvalidValue),
3839                         });
3840                 }
3841
3842                 let monitor_pending_revoke_and_ack = Readable::read(reader)?;
3843                 let monitor_pending_commitment_signed = Readable::read(reader)?;
3844
3845                 let monitor_pending_order = match <u8 as Readable<R>>::read(reader)? {
3846                         0 => None,
3847                         1 => Some(RAACommitmentOrder::CommitmentFirst),
3848                         2 => Some(RAACommitmentOrder::RevokeAndACKFirst),
3849                         _ => return Err(DecodeError::InvalidValue),
3850                 };
3851
3852                 let monitor_pending_forwards_count: u64 = Readable::read(reader)?;
3853                 let mut monitor_pending_forwards = Vec::with_capacity(cmp::min(monitor_pending_forwards_count as usize, OUR_MAX_HTLCS as usize));
3854                 for _ in 0..monitor_pending_forwards_count {
3855                         monitor_pending_forwards.push((Readable::read(reader)?, Readable::read(reader)?));
3856                 }
3857
3858                 let monitor_pending_failures_count: u64 = Readable::read(reader)?;
3859                 let mut monitor_pending_failures = Vec::with_capacity(cmp::min(monitor_pending_failures_count as usize, OUR_MAX_HTLCS as usize));
3860                 for _ in 0..monitor_pending_failures_count {
3861                         monitor_pending_failures.push((Readable::read(reader)?, Readable::read(reader)?, Readable::read(reader)?));
3862                 }
3863
3864                 let pending_update_fee = Readable::read(reader)?;
3865                 let holding_cell_update_fee = Readable::read(reader)?;
3866
3867                 let next_local_htlc_id = Readable::read(reader)?;
3868                 let next_remote_htlc_id = Readable::read(reader)?;
3869                 let channel_update_count = Readable::read(reader)?;
3870                 let feerate_per_kw = Readable::read(reader)?;
3871
3872                 let last_local_commitment_txn_count: u64 = Readable::read(reader)?;
3873                 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));
3874                 for _ in 0..last_local_commitment_txn_count {
3875                         last_local_commitment_txn.push(match Transaction::consensus_decode(reader.by_ref()) {
3876                                 Ok(tx) => tx,
3877                                 Err(_) => return Err(DecodeError::InvalidValue),
3878                         });
3879                 }
3880
3881                 let last_sent_closing_fee = match <u8 as Readable<R>>::read(reader)? {
3882                         0 => None,
3883                         1 => Some((Readable::read(reader)?, Readable::read(reader)?)),
3884                         _ => return Err(DecodeError::InvalidValue),
3885                 };
3886
3887                 let funding_tx_confirmed_in = Readable::read(reader)?;
3888                 let short_channel_id = Readable::read(reader)?;
3889
3890                 let last_block_connected = Readable::read(reader)?;
3891                 let funding_tx_confirmations = Readable::read(reader)?;
3892
3893                 let their_dust_limit_satoshis = Readable::read(reader)?;
3894                 let our_dust_limit_satoshis = Readable::read(reader)?;
3895                 let their_max_htlc_value_in_flight_msat = Readable::read(reader)?;
3896                 let their_channel_reserve_satoshis = Readable::read(reader)?;
3897                 let their_htlc_minimum_msat = Readable::read(reader)?;
3898                 let our_htlc_minimum_msat = Readable::read(reader)?;
3899                 let their_to_self_delay = Readable::read(reader)?;
3900                 let their_max_accepted_htlcs = Readable::read(reader)?;
3901                 let minimum_depth = Readable::read(reader)?;
3902
3903                 let their_funding_pubkey = Readable::read(reader)?;
3904                 let their_revocation_basepoint = Readable::read(reader)?;
3905                 let their_payment_basepoint = Readable::read(reader)?;
3906                 let their_delayed_payment_basepoint = Readable::read(reader)?;
3907                 let their_htlc_basepoint = Readable::read(reader)?;
3908                 let their_cur_commitment_point = Readable::read(reader)?;
3909
3910                 let their_prev_commitment_point = Readable::read(reader)?;
3911                 let their_node_id = Readable::read(reader)?;
3912
3913                 let their_shutdown_scriptpubkey = Readable::read(reader)?;
3914                 let (monitor_last_block, channel_monitor) = ReadableArgs::read(reader, logger.clone())?;
3915                 // We drop the ChannelMonitor's last block connected hash cause we don't actually bother
3916                 // doing full block connection operations on the internal CHannelMonitor copies
3917                 if monitor_last_block != last_block_connected {
3918                         return Err(DecodeError::InvalidValue);
3919                 }
3920
3921                 Ok(Channel {
3922                         user_id,
3923
3924                         config,
3925                         channel_id,
3926                         channel_state,
3927                         channel_outbound,
3928                         secp_ctx: Secp256k1::new(),
3929                         channel_value_satoshis,
3930
3931                         local_keys,
3932                         shutdown_pubkey,
3933
3934                         cur_local_commitment_transaction_number,
3935                         cur_remote_commitment_transaction_number,
3936                         value_to_self_msat,
3937
3938                         received_commitment_while_awaiting_raa,
3939                         pending_inbound_htlcs,
3940                         pending_outbound_htlcs,
3941                         holding_cell_htlc_updates,
3942
3943                         monitor_pending_revoke_and_ack,
3944                         monitor_pending_commitment_signed,
3945                         monitor_pending_order,
3946                         monitor_pending_forwards,
3947                         monitor_pending_failures,
3948
3949                         pending_update_fee,
3950                         holding_cell_update_fee,
3951                         next_local_htlc_id,
3952                         next_remote_htlc_id,
3953                         channel_update_count,
3954                         feerate_per_kw,
3955
3956                         #[cfg(debug_assertions)]
3957                         max_commitment_tx_output_local: ::std::sync::Mutex::new((0, 0)),
3958                         #[cfg(debug_assertions)]
3959                         max_commitment_tx_output_remote: ::std::sync::Mutex::new((0, 0)),
3960
3961                         last_local_commitment_txn,
3962
3963                         last_sent_closing_fee,
3964
3965                         funding_tx_confirmed_in,
3966                         short_channel_id,
3967                         last_block_connected,
3968                         funding_tx_confirmations,
3969
3970                         their_dust_limit_satoshis,
3971                         our_dust_limit_satoshis,
3972                         their_max_htlc_value_in_flight_msat,
3973                         their_channel_reserve_satoshis,
3974                         their_htlc_minimum_msat,
3975                         our_htlc_minimum_msat,
3976                         their_to_self_delay,
3977                         their_max_accepted_htlcs,
3978                         minimum_depth,
3979
3980                         their_funding_pubkey,
3981                         their_revocation_basepoint,
3982                         their_payment_basepoint,
3983                         their_delayed_payment_basepoint,
3984                         their_htlc_basepoint,
3985                         their_cur_commitment_point,
3986
3987                         their_prev_commitment_point,
3988                         their_node_id,
3989
3990                         their_shutdown_scriptpubkey,
3991
3992                         channel_monitor,
3993
3994                         logger,
3995                 })
3996         }
3997 }
3998
3999 #[cfg(test)]
4000 mod tests {
4001         use bitcoin::util::bip143;
4002         use bitcoin::consensus::encode::serialize;
4003         use bitcoin::blockdata::script::{Script, Builder};
4004         use bitcoin::blockdata::transaction::Transaction;
4005         use bitcoin::blockdata::opcodes;
4006         use bitcoin_hashes::hex::FromHex;
4007         use hex;
4008         use ln::channelmanager::{HTLCSource, PaymentPreimage, PaymentHash};
4009         use ln::channel::{Channel,ChannelKeys,InboundHTLCOutput,OutboundHTLCOutput,InboundHTLCState,OutboundHTLCState,HTLCOutputInCommitment,TxCreationKeys};
4010         use ln::channel::MAX_FUNDING_SATOSHIS;
4011         use ln::chan_utils;
4012         use chain::chaininterface::{FeeEstimator,ConfirmationTarget};
4013         use chain::keysinterface::KeysInterface;
4014         use chain::transaction::OutPoint;
4015         use util::config::UserConfig;
4016         use util::test_utils;
4017         use util::logger::Logger;
4018         use secp256k1::{Secp256k1,Message,Signature};
4019         use secp256k1::key::{SecretKey,PublicKey};
4020         use bitcoin_hashes::sha256::Hash as Sha256;
4021         use bitcoin_hashes::sha256d::Hash as Sha256dHash;
4022         use bitcoin_hashes::hash160::Hash as Hash160;
4023         use bitcoin_hashes::Hash;
4024         use std::sync::Arc;
4025
4026         struct TestFeeEstimator {
4027                 fee_est: u64
4028         }
4029         impl FeeEstimator for TestFeeEstimator {
4030                 fn get_est_sat_per_1000_weight(&self, _: ConfirmationTarget) -> u64 {
4031                         self.fee_est
4032                 }
4033         }
4034
4035         #[test]
4036         fn test_max_funding_satoshis() {
4037                 assert!(MAX_FUNDING_SATOSHIS <= 21_000_000 * 100_000_000,
4038                         "MAX_FUNDING_SATOSHIS is greater than all satoshis in existence");
4039         }
4040
4041         struct Keys {
4042                 chan_keys: ChannelKeys,
4043         }
4044         impl KeysInterface for Keys {
4045                 fn get_node_secret(&self) -> SecretKey { panic!(); }
4046                 fn get_destination_script(&self) -> Script {
4047                         let secp_ctx = Secp256k1::signing_only();
4048                         let channel_monitor_claim_key = SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap();
4049                         let our_channel_monitor_claim_key_hash = Hash160::hash(&PublicKey::from_secret_key(&secp_ctx, &channel_monitor_claim_key).serialize());
4050                         Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&our_channel_monitor_claim_key_hash[..]).into_script()
4051                 }
4052
4053                 fn get_shutdown_pubkey(&self) -> PublicKey {
4054                         let secp_ctx = Secp256k1::signing_only();
4055                         let channel_close_key = SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap();
4056                         PublicKey::from_secret_key(&secp_ctx, &channel_close_key)
4057                 }
4058
4059                 fn get_channel_keys(&self, _inbound: bool) -> ChannelKeys { self.chan_keys.clone() }
4060                 fn get_session_key(&self) -> SecretKey { panic!(); }
4061                 fn get_channel_id(&self) -> [u8; 32] { [0; 32] }
4062         }
4063
4064         #[test]
4065         fn outbound_commitment_test() {
4066                 // Test vectors from BOLT 3 Appendix C:
4067                 let feeest = TestFeeEstimator{fee_est: 15000};
4068                 let logger : Arc<Logger> = Arc::new(test_utils::TestLogger::new());
4069                 let secp_ctx = Secp256k1::new();
4070
4071                 let chan_keys = ChannelKeys {
4072                         funding_key: SecretKey::from_slice(&hex::decode("30ff4956bbdd3222d44cc5e8a1261dab1e07957bdac5ae88fe3261ef321f3749").unwrap()[..]).unwrap(),
4073                         payment_base_key: SecretKey::from_slice(&hex::decode("1111111111111111111111111111111111111111111111111111111111111111").unwrap()[..]).unwrap(),
4074                         delayed_payment_base_key: SecretKey::from_slice(&hex::decode("3333333333333333333333333333333333333333333333333333333333333333").unwrap()[..]).unwrap(),
4075                         htlc_base_key: SecretKey::from_slice(&hex::decode("1111111111111111111111111111111111111111111111111111111111111111").unwrap()[..]).unwrap(),
4076
4077                         // These aren't set in the test vectors:
4078                         revocation_base_key: SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap(),
4079                         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],
4080                 };
4081                 assert_eq!(PublicKey::from_secret_key(&secp_ctx, &chan_keys.funding_key).serialize()[..],
4082                                 hex::decode("023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb").unwrap()[..]);
4083                 let keys_provider: Arc<KeysInterface> = Arc::new(Keys { chan_keys });
4084
4085                 let their_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
4086                 let mut config = UserConfig::new();
4087                 config.channel_options.announced_channel = false;
4088                 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
4089                 chan.their_to_self_delay = 144;
4090                 chan.our_dust_limit_satoshis = 546;
4091
4092                 let funding_info = OutPoint::new(Sha256dHash::from_hex("8984484a580b825b9972d7adb15050b3ab624ccd731946b3eeddb92f4e7ef6be").unwrap(), 0);
4093                 chan.channel_monitor.set_funding_info((funding_info, Script::new()));
4094
4095                 chan.their_payment_basepoint = Some(PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("4444444444444444444444444444444444444444444444444444444444444444").unwrap()[..]).unwrap()));
4096                 assert_eq!(chan.their_payment_basepoint.unwrap().serialize()[..],
4097                                 hex::decode("032c0b7cf95324a07d05398b240174dc0c2be444d96b159aa6c7f7b1e668680991").unwrap()[..]);
4098
4099                 chan.their_funding_pubkey = Some(PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("1552dfba4f6cf29a62a0af13c8d6981d36d0ef8d61ba10fb0fe90da7634d7e13").unwrap()[..]).unwrap()));
4100                 assert_eq!(chan.their_funding_pubkey.unwrap().serialize()[..],
4101                                 hex::decode("030e9f7b623d2ccc7c9bd44d66d5ce21ce504c0acf6385a132cec6d3c39fa711c1").unwrap()[..]);
4102
4103                 chan.their_htlc_basepoint = Some(PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("4444444444444444444444444444444444444444444444444444444444444444").unwrap()[..]).unwrap()));
4104                 assert_eq!(chan.their_htlc_basepoint.unwrap().serialize()[..],
4105                                 hex::decode("032c0b7cf95324a07d05398b240174dc0c2be444d96b159aa6c7f7b1e668680991").unwrap()[..]);
4106
4107                 chan.their_revocation_basepoint = Some(PublicKey::from_slice(&hex::decode("02466d7fcae563e5cb09a0d1870bb580344804617879a14949cf22285f1bae3f27").unwrap()[..]).unwrap());
4108
4109                 // We can't just use build_local_transaction_keys here as the per_commitment_secret is not
4110                 // derived from a commitment_seed, so instead we copy it here and call
4111                 // build_commitment_transaction.
4112                 let delayed_payment_base = PublicKey::from_secret_key(&secp_ctx, &chan.local_keys.delayed_payment_base_key);
4113                 let per_commitment_secret = SecretKey::from_slice(&hex::decode("1f1e1d1c1b1a191817161514131211100f0e0d0c0b0a09080706050403020100").unwrap()[..]).unwrap();
4114                 let per_commitment_point = PublicKey::from_secret_key(&secp_ctx, &per_commitment_secret);
4115                 let htlc_basepoint = PublicKey::from_secret_key(&secp_ctx, &chan.local_keys.htlc_base_key);
4116                 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();
4117
4118                 let mut unsigned_tx: (Transaction, Vec<HTLCOutputInCommitment>);
4119
4120                 macro_rules! test_commitment {
4121                         ( $their_sig_hex: expr, $our_sig_hex: expr, $tx_hex: expr) => {
4122                                 unsigned_tx = {
4123                                         let mut res = chan.build_commitment_transaction(0xffffffffffff - 42, &keys, true, false, chan.feerate_per_kw);
4124                                         let htlcs = res.2.drain(..)
4125                                                 .filter_map(|(htlc, _)| if htlc.transaction_output_index.is_some() { Some(htlc) } else { None })
4126                                                 .collect();
4127                                         (res.0, htlcs)
4128                                 };
4129                                 let their_signature = Signature::from_der(&hex::decode($their_sig_hex).unwrap()[..]).unwrap();
4130                                 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();
4131                                 secp_ctx.verify(&sighash, &their_signature, &chan.their_funding_pubkey.unwrap()).unwrap();
4132
4133                                 chan.sign_commitment_transaction(&mut unsigned_tx.0, &their_signature);
4134
4135                                 assert_eq!(serialize(&unsigned_tx.0)[..],
4136                                                 hex::decode($tx_hex).unwrap()[..]);
4137                         };
4138                 }
4139
4140                 macro_rules! test_htlc_output {
4141                         ( $htlc_idx: expr, $their_sig_hex: expr, $our_sig_hex: expr, $tx_hex: expr ) => {
4142                                 let remote_signature = Signature::from_der(&hex::decode($their_sig_hex).unwrap()[..]).unwrap();
4143
4144                                 let ref htlc = unsigned_tx.1[$htlc_idx];
4145                                 let mut htlc_tx = chan.build_htlc_transaction(&unsigned_tx.0.txid(), &htlc, true, &keys, chan.feerate_per_kw);
4146                                 let htlc_redeemscript = chan_utils::get_htlc_redeemscript(&htlc, &keys);
4147                                 let htlc_sighash = Message::from_slice(&bip143::SighashComponents::new(&htlc_tx).sighash_all(&htlc_tx.input[0], &htlc_redeemscript, htlc.amount_msat / 1000)[..]).unwrap();
4148                                 secp_ctx.verify(&htlc_sighash, &remote_signature, &keys.b_htlc_key).unwrap();
4149
4150                                 let mut preimage: Option<PaymentPreimage> = None;
4151                                 if !htlc.offered {
4152                                         for i in 0..5 {
4153                                                 let out = PaymentHash(Sha256::hash(&[i; 32]).into_inner());
4154                                                 if out == htlc.payment_hash {
4155                                                         preimage = Some(PaymentPreimage([i; 32]));
4156                                                 }
4157                                         }
4158
4159                                         assert!(preimage.is_some());
4160                                 }
4161
4162                                 chan.sign_htlc_transaction(&mut htlc_tx, &remote_signature, &preimage, &htlc, &keys).unwrap();
4163                                 assert_eq!(serialize(&htlc_tx)[..],
4164                                                 hex::decode($tx_hex).unwrap()[..]);
4165                         };
4166                 }
4167
4168                 {
4169                         // simple commitment tx with no HTLCs
4170                         chan.value_to_self_msat = 7000000000;
4171
4172                         test_commitment!("3045022100f51d2e566a70ba740fc5d8c0f07b9b93d2ed741c3c0860c613173de7d39e7968022041376d520e9c0e1ad52248ddf4b22e12be8763007df977253ef45a4ca3bdb7c0",
4173                                          "3044022051b75c73198c6deee1a875871c3961832909acd297c6b908d59e3319e5185a46022055c419379c5051a78d00dbbce11b5b664a0c22815fbcc6fcef6b1937c3836939",
4174                                          "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");
4175                 }
4176
4177                 chan.pending_inbound_htlcs.push({
4178                         let mut out = InboundHTLCOutput{
4179                                 htlc_id: 0,
4180                                 amount_msat: 1000000,
4181                                 cltv_expiry: 500,
4182                                 payment_hash: PaymentHash([0; 32]),
4183                                 state: InboundHTLCState::Committed,
4184                         };
4185                         out.payment_hash.0 = Sha256::hash(&hex::decode("0000000000000000000000000000000000000000000000000000000000000000").unwrap()).into_inner();
4186                         out
4187                 });
4188                 chan.pending_inbound_htlcs.push({
4189                         let mut out = InboundHTLCOutput{
4190                                 htlc_id: 1,
4191                                 amount_msat: 2000000,
4192                                 cltv_expiry: 501,
4193                                 payment_hash: PaymentHash([0; 32]),
4194                                 state: InboundHTLCState::Committed,
4195                         };
4196                         out.payment_hash.0 = Sha256::hash(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()).into_inner();
4197                         out
4198                 });
4199                 chan.pending_outbound_htlcs.push({
4200                         let mut out = OutboundHTLCOutput{
4201                                 htlc_id: 2,
4202                                 amount_msat: 2000000,
4203                                 cltv_expiry: 502,
4204                                 payment_hash: PaymentHash([0; 32]),
4205                                 state: OutboundHTLCState::Committed,
4206                                 source: HTLCSource::dummy(),
4207                         };
4208                         out.payment_hash.0 = Sha256::hash(&hex::decode("0202020202020202020202020202020202020202020202020202020202020202").unwrap()).into_inner();
4209                         out
4210                 });
4211                 chan.pending_outbound_htlcs.push({
4212                         let mut out = OutboundHTLCOutput{
4213                                 htlc_id: 3,
4214                                 amount_msat: 3000000,
4215                                 cltv_expiry: 503,
4216                                 payment_hash: PaymentHash([0; 32]),
4217                                 state: OutboundHTLCState::Committed,
4218                                 source: HTLCSource::dummy(),
4219                         };
4220                         out.payment_hash.0 = Sha256::hash(&hex::decode("0303030303030303030303030303030303030303030303030303030303030303").unwrap()).into_inner();
4221                         out
4222                 });
4223                 chan.pending_inbound_htlcs.push({
4224                         let mut out = InboundHTLCOutput{
4225                                 htlc_id: 4,
4226                                 amount_msat: 4000000,
4227                                 cltv_expiry: 504,
4228                                 payment_hash: PaymentHash([0; 32]),
4229                                 state: InboundHTLCState::Committed,
4230                         };
4231                         out.payment_hash.0 = Sha256::hash(&hex::decode("0404040404040404040404040404040404040404040404040404040404040404").unwrap()).into_inner();
4232                         out
4233                 });
4234
4235                 {
4236                         // commitment tx with all five HTLCs untrimmed (minimum feerate)
4237                         chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
4238                         chan.feerate_per_kw = 0;
4239
4240                         test_commitment!("304402204fd4928835db1ccdfc40f5c78ce9bd65249b16348df81f0c44328dcdefc97d630220194d3869c38bc732dd87d13d2958015e2fc16829e74cd4377f84d215c0b70606",
4241                                          "30440220275b0c325a5e9355650dc30c0eccfbc7efb23987c24b556b9dfdd40effca18d202206caceb2c067836c51f296740c7ae807ffcbfbf1dd3a0d56b6de9a5b247985f06",
4242                                          "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");
4243
4244                         assert_eq!(unsigned_tx.1.len(), 5);
4245
4246                         test_htlc_output!(0,
4247                                           "304402206a6e59f18764a5bf8d4fa45eebc591566689441229c918b480fb2af8cc6a4aeb02205248f273be447684b33e3c8d1d85a8e0ca9fa0bae9ae33f0527ada9c162919a6",
4248                                           "304402207cb324fa0de88f452ffa9389678127ebcf4cabe1dd848b8e076c1a1962bf34720220116ed922b12311bd602d67e60d2529917f21c5b82f25ff6506c0f87886b4dfd5",
4249                                           "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");
4250
4251                         test_htlc_output!(1,
4252                                           "3045022100d5275b3619953cb0c3b5aa577f04bc512380e60fa551762ce3d7a1bb7401cff9022037237ab0dac3fe100cde094e82e2bed9ba0ed1bb40154b48e56aa70f259e608b",
4253                                           "3045022100c89172099507ff50f4c925e6c5150e871fb6e83dd73ff9fbb72f6ce829a9633f02203a63821d9162e99f9be712a68f9e589483994feae2661e4546cd5b6cec007be5",
4254                                           "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");
4255
4256                         test_htlc_output!(2,
4257                                           "304402201b63ec807771baf4fdff523c644080de17f1da478989308ad13a58b51db91d360220568939d38c9ce295adba15665fa68f51d967e8ed14a007b751540a80b325f202",
4258                                           "3045022100def389deab09cee69eaa1ec14d9428770e45bcbe9feb46468ecf481371165c2f022015d2e3c46600b2ebba8dcc899768874cc6851fd1ecb3fffd15db1cc3de7e10da",
4259                                           "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");
4260
4261                         test_htlc_output!(3,
4262                                           "3045022100daee1808f9861b6c3ecd14f7b707eca02dd6bdfc714ba2f33bc8cdba507bb182022026654bf8863af77d74f51f4e0b62d461a019561bb12acb120d3f7195d148a554",
4263                                           "30440220643aacb19bbb72bd2b635bc3f7375481f5981bace78cdd8319b2988ffcc6704202203d27784ec8ad51ed3bd517a05525a5139bb0b755dd719e0054332d186ac08727",
4264                                           "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");
4265
4266                         test_htlc_output!(4,
4267                                           "304402207e0410e45454b0978a623f36a10626ef17b27d9ad44e2760f98cfa3efb37924f0220220bd8acd43ecaa916a80bd4f919c495a2c58982ce7c8625153f8596692a801d",
4268                                           "30440220549e80b4496803cbc4a1d09d46df50109f546d43fbbf86cd90b174b1484acd5402205f12a4f995cb9bded597eabfee195a285986aa6d93ae5bb72507ebc6a4e2349e",
4269                                           "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");
4270                 }
4271
4272                 {
4273                         // commitment tx with seven outputs untrimmed (maximum feerate)
4274                         chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
4275                         chan.feerate_per_kw = 647;
4276
4277                         test_commitment!("3045022100a5c01383d3ec646d97e40f44318d49def817fcd61a0ef18008a665b3e151785502203e648efddd5838981ef55ec954be69c4a652d021e6081a100d034de366815e9b",
4278                                          "304502210094bfd8f5572ac0157ec76a9551b6c5216a4538c07cd13a51af4a54cb26fa14320220768efce8ce6f4a5efac875142ff19237c011343670adf9c7ac69704a120d1163",
4279                                          "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");
4280
4281                         assert_eq!(unsigned_tx.1.len(), 5);
4282
4283                         test_htlc_output!(0,
4284                                           "30440220385a5afe75632f50128cbb029ee95c80156b5b4744beddc729ad339c9ca432c802202ba5f48550cad3379ac75b9b4fedb86a35baa6947f16ba5037fb8b11ab343740",
4285                                           "304402205999590b8a79fa346e003a68fd40366397119b2b0cdf37b149968d6bc6fbcc4702202b1e1fb5ab7864931caed4e732c359e0fe3d86a548b557be2246efb1708d579a",
4286                                           "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");
4287
4288                         test_htlc_output!(1,
4289                                           "304402207ceb6678d4db33d2401fdc409959e57c16a6cb97a30261d9c61f29b8c58d34b90220084b4a17b4ca0e86f2d798b3698ca52de5621f2ce86f80bed79afa66874511b0",
4290                                           "304402207ff03eb0127fc7c6cae49cc29e2a586b98d1e8969cf4a17dfa50b9c2647720b902205e2ecfda2252956c0ca32f175080e75e4e390e433feb1f8ce9f2ba55648a1dac",
4291                                           "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");
4292
4293                         test_htlc_output!(2,
4294                                           "304402206a401b29a0dff0d18ec903502c13d83e7ec019450113f4a7655a4ce40d1f65ba0220217723a084e727b6ca0cc8b6c69c014a7e4a01fcdcba3e3993f462a3c574d833",
4295                                           "3045022100d50d067ca625d54e62df533a8f9291736678d0b86c28a61bb2a80cf42e702d6e02202373dde7e00218eacdafb9415fe0e1071beec1857d1af3c6a201a44cbc47c877",
4296                                           "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");
4297
4298                         test_htlc_output!(3,
4299                                           "30450221009b1c987ba599ee3bde1dbca776b85481d70a78b681a8d84206723e2795c7cac002207aac84ad910f8598c4d1c0ea2e3399cf6627a4e3e90131315bc9f038451ce39d",
4300                                           "3045022100db9dc65291077a52728c622987e9895b7241d4394d6dcb916d7600a3e8728c22022036ee3ee717ba0bb5c45ee84bc7bbf85c0f90f26ae4e4a25a6b4241afa8a3f1cb",
4301                                           "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");
4302
4303                         test_htlc_output!(4,
4304                                           "3045022100cc28030b59f0914f45b84caa983b6f8effa900c952310708c2b5b00781117022022027ba2ccdf94d03c6d48b327f183f6e28c8a214d089b9227f94ac4f85315274f0",
4305                                           "304402202d1a3c0d31200265d2a2def2753ead4959ae20b4083e19553acfffa5dfab60bf022020ede134149504e15b88ab261a066de49848411e15e70f9e6a5462aec2949f8f",
4306                                           "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");
4307                 }
4308
4309                 {
4310                         // commitment tx with six outputs untrimmed (minimum feerate)
4311                         chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
4312                         chan.feerate_per_kw = 648;
4313
4314                         test_commitment!("3044022072714e2fbb93cdd1c42eb0828b4f2eff143f717d8f26e79d6ada4f0dcb681bbe02200911be4e5161dd6ebe59ff1c58e1997c4aea804f81db6b698821db6093d7b057",
4315                                          "3045022100a2270d5950c89ae0841233f6efea9c951898b301b2e89e0adbd2c687b9f32efa02207943d90f95b9610458e7c65a576e149750ff3accaacad004cd85e70b235e27de",
4316                                          "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");
4317
4318                         assert_eq!(unsigned_tx.1.len(), 4);
4319
4320                         test_htlc_output!(0,
4321                                           "3044022062ef2e77591409d60d7817d9bb1e71d3c4a2931d1a6c7c8307422c84f001a251022022dad9726b0ae3fe92bda745a06f2c00f92342a186d84518588cf65f4dfaada8",
4322                                           "3045022100a4c574f00411dd2f978ca5cdc1b848c311cd7849c087ad2f21a5bce5e8cc5ae90220090ae39a9bce2fb8bc879d7e9f9022df249f41e25e51f1a9bf6447a9eeffc098",
4323                                           "02000000000101579c183eca9e8236a5d7f5dcd79cfec32c497fdc0ec61533cde99ecd436cadd10000000000000000000123060000000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e0500473044022062ef2e77591409d60d7817d9bb1e71d3c4a2931d1a6c7c8307422c84f001a251022022dad9726b0ae3fe92bda745a06f2c00f92342a186d84518588cf65f4dfaada801483045022100a4c574f00411dd2f978ca5cdc1b848c311cd7849c087ad2f21a5bce5e8cc5ae90220090ae39a9bce2fb8bc879d7e9f9022df249f41e25e51f1a9bf6447a9eeffc09801008576a91414011f7254d96b819c76986c277d115efce6f7b58763ac67210394854aa6eab5b2a8122cc726e9dded053a2184d88256816826d6231c068d4a5b7c820120876475527c21030d417a46946384f88d5f3337267c5e579765875dc4daca813e21734b140639e752ae67a914b43e1b38138a41b37f7cd9a1d274bc63e3a9b5d188ac6868f6010000");
4324
4325                         test_htlc_output!(1,
4326                                           "3045022100e968cbbb5f402ed389fdc7f6cd2a80ed650bb42c79aeb2a5678444af94f6c78502204b47a1cb24ab5b0b6fe69fe9cfc7dba07b9dd0d8b95f372c1d9435146a88f8d4",
4327                                           "304402207679cf19790bea76a733d2fa0672bd43ab455687a068f815a3d237581f57139a0220683a1a799e102071c206b207735ca80f627ab83d6616b4bcd017c5d79ef3e7d0",
4328                                           "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");
4329
4330                         test_htlc_output!(2,
4331                                           "3045022100aa91932e305292cf9969cc23502bbf6cef83a5df39c95ad04a707c4f4fed5c7702207099fc0f3a9bfe1e7683c0e9aa5e76c5432eb20693bf4cb182f04d383dc9c8c2",
4332                                           "304402200df76fea718745f3c529bac7fd37923e7309ce38b25c0781e4cf514dd9ef8dc802204172295739dbae9fe0474dcee3608e3433b4b2af3a2e6787108b02f894dcdda3",
4333                                           "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");
4334
4335                         test_htlc_output!(3,
4336                                           "3044022035cac88040a5bba420b1c4257235d5015309113460bc33f2853cd81ca36e632402202fc94fd3e81e9d34a9d01782a0284f3044370d03d60f3fc041e2da088d2de58f",
4337                                           "304402200daf2eb7afd355b4caf6fb08387b5f031940ea29d1a9f35071288a839c9039e4022067201b562456e7948616c13acb876b386b511599b58ac1d94d127f91c50463a6",
4338                                           "02000000000101579c183eca9e8236a5d7f5dcd79cfec32c497fdc0ec61533cde99ecd436cadd103000000000000000001d90d0000000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e0500473044022035cac88040a5bba420b1c4257235d5015309113460bc33f2853cd81ca36e632402202fc94fd3e81e9d34a9d01782a0284f3044370d03d60f3fc041e2da088d2de58f0147304402200daf2eb7afd355b4caf6fb08387b5f031940ea29d1a9f35071288a839c9039e4022067201b562456e7948616c13acb876b386b511599b58ac1d94d127f91c50463a6012004040404040404040404040404040404040404040404040404040404040404048a76a91414011f7254d96b819c76986c277d115efce6f7b58763ac67210394854aa6eab5b2a8122cc726e9dded053a2184d88256816826d6231c068d4a5b7c8201208763a91418bc1a114ccf9c052d3d23e28d3b0a9d1227434288527c21030d417a46946384f88d5f3337267c5e579765875dc4daca813e21734b140639e752ae677502f801b175ac686800000000");
4339                 }
4340
4341                 {
4342                         // commitment tx with six outputs untrimmed (maximum feerate)
4343                         chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
4344                         chan.feerate_per_kw = 2069;
4345
4346                         test_commitment!("3044022001d55e488b8b035b2dd29d50b65b530923a416d47f377284145bc8767b1b6a75022019bb53ddfe1cefaf156f924777eaaf8fdca1810695a7d0a247ad2afba8232eb4",
4347                                          "304402203ca8f31c6a47519f83255dc69f1894d9a6d7476a19f498d31eaf0cd3a85eeb63022026fd92dc752b33905c4c838c528b692a8ad4ced959990b5d5ee2ff940fa90eea",
4348                                          "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");
4349
4350                         assert_eq!(unsigned_tx.1.len(), 4);
4351
4352                         test_htlc_output!(0,
4353                                           "3045022100d1cf354de41c1369336cf85b225ed033f1f8982a01be503668df756a7e668b66022001254144fb4d0eecc61908fccc3388891ba17c5d7a1a8c62bdd307e5a513f992",
4354                                           "3044022056eb1af429660e45a1b0b66568cb8c4a3aa7e4c9c292d5d6c47f86ebf2c8838f022065c3ac4ebe980ca7a41148569be4ad8751b0a724a41405697ec55035dae66402",
4355                                           "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");
4356
4357                         test_htlc_output!(1,
4358                                           "3045022100d065569dcb94f090345402736385efeb8ea265131804beac06dd84d15dd2d6880220664feb0b4b2eb985fadb6ec7dc58c9334ea88ce599a9be760554a2d4b3b5d9f4",
4359                                           "3045022100914bb232cd4b2690ee3d6cb8c3713c4ac9c4fb925323068d8b07f67c8541f8d9022057152f5f1615b793d2d45aac7518989ae4fe970f28b9b5c77504799d25433f7f",
4360                                           "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");
4361
4362                         test_htlc_output!(2,
4363                                           "3045022100d4e69d363de993684eae7b37853c40722a4c1b4a7b588ad7b5d8a9b5006137a102207a069c628170ee34be5612747051bdcc087466dbaa68d5756ea81c10155aef18",
4364                                           "304402200e362443f7af830b419771e8e1614fc391db3a4eb799989abfc5ab26d6fcd032022039ab0cad1c14dfbe9446bf847965e56fe016e0cbcf719fd18c1bfbf53ecbd9f9",
4365                                           "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");
4366
4367                         test_htlc_output!(3,
4368                                           "30450221008ec888e36e4a4b3dc2ed6b823319855b2ae03006ca6ae0d9aa7e24bfc1d6f07102203b0f78885472a67ff4fe5916c0bb669487d659527509516fc3a08e87a2cc0a7c",
4369                                           "304402202c3e14282b84b02705dfd00a6da396c9fe8a8bcb1d3fdb4b20a4feba09440e8b02202b058b39aa9b0c865b22095edcd9ff1f71bbfe20aa4993755e54d042755ed0d5",
4370                                           "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");
4371                 }
4372
4373                 {
4374                         // commitment tx with five outputs untrimmed (minimum feerate)
4375                         chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
4376                         chan.feerate_per_kw = 2070;
4377
4378                         test_commitment!("3045022100f2377f7a67b7fc7f4e2c0c9e3a7de935c32417f5668eda31ea1db401b7dc53030220415fdbc8e91d0f735e70c21952342742e25249b0d062d43efbfc564499f37526",
4379                                          "30440220443cb07f650aebbba14b8bc8d81e096712590f524c5991ac0ed3bbc8fd3bd0c7022028a635f548e3ca64b19b69b1ea00f05b22752f91daf0b6dab78e62ba52eb7fd0",
4380                                          "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");
4381
4382                         assert_eq!(unsigned_tx.1.len(), 3);
4383
4384                         test_htlc_output!(0,
4385                                           "3045022100eed143b1ee4bed5dc3cde40afa5db3e7354cbf9c44054b5f713f729356f08cf7022077161d171c2bbd9badf3c9934de65a4918de03bbac1450f715275f75b103f891",
4386                                           "3045022100a0d043ed533e7fb1911e0553d31a8e2f3e6de19dbc035257f29d747c5e02f1f5022030cd38d8e84282175d49c1ebe0470db3ebd59768cf40780a784e248a43904fb8",
4387                                           "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");
4388
4389                         test_htlc_output!(1,
4390                                           "3044022071e9357619fd8d29a411dc053b326a5224c5d11268070e88ecb981b174747c7a02202b763ae29a9d0732fa8836dd8597439460b50472183f420021b768981b4f7cf6",
4391                                           "3045022100adb1d679f65f96178b59f23ed37d3b70443118f345224a07ecb043eee2acc157022034d24524fe857144a3bcfff3065a9994d0a6ec5f11c681e49431d573e242612d",
4392                                           "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");
4393
4394                         test_htlc_output!(2,
4395                                           "3045022100c9458a4d2cbb741705577deb0a890e5cb90ee141be0400d3162e533727c9cb2102206edcf765c5dc5e5f9b976ea8149bf8607b5a0efb30691138e1231302b640d2a4",
4396                                           "304402200831422aa4e1ee6d55e0b894201770a8f8817a189356f2d70be76633ffa6a6f602200dd1b84a4855dc6727dd46c98daae43dfc70889d1ba7ef0087529a57c06e5e04",
4397                                           "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");
4398                 }
4399
4400                 {
4401                         // commitment tx with five outputs untrimmed (maximum feerate)
4402                         chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
4403                         chan.feerate_per_kw = 2194;
4404
4405                         test_commitment!("3045022100d33c4e541aa1d255d41ea9a3b443b3b822ad8f7f86862638aac1f69f8f760577022007e2a18e6931ce3d3a804b1c78eda1de17dbe1fb7a95488c9a4ec86203953348",
4406                                          "304402203b1b010c109c2ecbe7feb2d259b9c4126bd5dc99ee693c422ec0a5781fe161ba0220571fe4e2c649dea9c7aaf7e49b382962f6a3494963c97d80fef9a430ca3f7061",
4407                                          "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");
4408
4409                         assert_eq!(unsigned_tx.1.len(), 3);
4410
4411                         test_htlc_output!(0,
4412                                           "30450221009ed2f0a67f99e29c3c8cf45c08207b765980697781bb727fe0b1416de0e7622902206052684229bc171419ed290f4b615c943f819c0262414e43c5b91dcf72ddcf44",
4413                                           "3044022004ad5f04ae69c71b3b141d4db9d0d4c38d84009fb3cfeeae6efdad414487a9a0022042d3fe1388c1ff517d1da7fb4025663d372c14728ed52dc88608363450ff6a2f",
4414                                           "02000000000101fb824d4e4dafc0f567789dee3a6bce8d411fe80f5563d8cdfdcc7d7e4447d43a0000000000000000000122020000000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e05004830450221009ed2f0a67f99e29c3c8cf45c08207b765980697781bb727fe0b1416de0e7622902206052684229bc171419ed290f4b615c943f819c0262414e43c5b91dcf72ddcf4401473044022004ad5f04ae69c71b3b141d4db9d0d4c38d84009fb3cfeeae6efdad414487a9a0022042d3fe1388c1ff517d1da7fb4025663d372c14728ed52dc88608363450ff6a2f01008576a91414011f7254d96b819c76986c277d115efce6f7b58763ac67210394854aa6eab5b2a8122cc726e9dded053a2184d88256816826d6231c068d4a5b7c820120876475527c21030d417a46946384f88d5f3337267c5e579765875dc4daca813e21734b140639e752ae67a914b43e1b38138a41b37f7cd9a1d274bc63e3a9b5d188ac6868f6010000");
4415
4416                         test_htlc_output!(1,
4417                                           "30440220155d3b90c67c33a8321996a9be5b82431b0c126613be751d400669da9d5c696702204318448bcd48824439d2c6a70be6e5747446be47ff45977cf41672bdc9b6b12d",
4418                                           "304402201707050c870c1f77cc3ed58d6d71bf281de239e9eabd8ef0955bad0d7fe38dcc02204d36d80d0019b3a71e646a08fa4a5607761d341ae8be371946ebe437c289c915",
4419                                           "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");
4420
4421                         test_htlc_output!(2,
4422                                           "3045022100a12a9a473ece548584aabdd051779025a5ed4077c4b7aa376ec7a0b1645e5a48022039490b333f53b5b3e2ddde1d809e492cba2b3e5fc3a436cd3ffb4cd3d500fa5a",
4423                                           "3045022100ff200bc934ab26ce9a559e998ceb0aee53bc40368e114ab9d3054d9960546e2802202496856ca163ac12c143110b6b3ac9d598df7254f2e17b3b94c3ab5301f4c3b0",
4424                                           "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");
4425                 }
4426
4427                 {
4428                         // commitment tx with four outputs untrimmed (minimum feerate)
4429                         chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
4430                         chan.feerate_per_kw = 2195;
4431
4432                         test_commitment!("304402205e2f76d4657fb732c0dfc820a18a7301e368f5799e06b7828007633741bda6df0220458009ae59d0c6246065c419359e05eb2a4b4ef4a1b310cc912db44eb7924298",
4433                                          "304402203b12d44254244b8ff3bb4129b0920fd45120ab42f553d9976394b099d500c99e02205e95bb7a3164852ef0c48f9e0eaf145218f8e2c41251b231f03cbdc4f29a5429",
4434                                          "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");
4435
4436                         assert_eq!(unsigned_tx.1.len(), 2);
4437
4438                         test_htlc_output!(0,
4439                                           "3045022100a8a78fa1016a5c5c3704f2e8908715a3cef66723fb95f3132ec4d2d05cd84fb4022025ac49287b0861ec21932405f5600cbce94313dbde0e6c5d5af1b3366d8afbfc",
4440                                           "3045022100be6ae1977fd7b630a53623f3f25c542317ccfc2b971782802a4f1ef538eb22b402207edc4d0408f8f38fd3c7365d1cfc26511b7cd2d4fecd8b005fba3cd5bc704390",
4441                                           "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");
4442
4443                         test_htlc_output!(1,
4444                                           "3045022100e769cb156aa2f7515d126cef7a69968629620ce82afcaa9e210969de6850df4602200b16b3f3486a229a48aadde520dbee31ae340dbadaffae74fbb56681fef27b92",
4445                                           "30440220665b9cb4a978c09d1ca8977a534999bc8a49da624d0c5439451dd69cde1a003d022070eae0620f01f3c1bd029cc1488da13fb40fdab76f396ccd335479a11c5276d8",
4446                                           "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");
4447                 }
4448
4449                 {
4450                         // commitment tx with four outputs untrimmed (maximum feerate)
4451                         chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
4452                         chan.feerate_per_kw = 3702;
4453
4454                         test_commitment!("3045022100c1a3b0b60ca092ed5080121f26a74a20cec6bdee3f8e47bae973fcdceb3eda5502207d467a9873c939bf3aa758014ae67295fedbca52412633f7e5b2670fc7c381c1",
4455                                          "304402200e930a43c7951162dc15a2b7344f48091c74c70f7024e7116e900d8bcfba861c022066fa6cbda3929e21daa2e7e16a4b948db7e8919ef978402360d1095ffdaff7b0",
4456                                          "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");
4457
4458                         assert_eq!(unsigned_tx.1.len(), 2);
4459
4460                         test_htlc_output!(0,
4461                                           "3045022100dfb73b4fe961b31a859b2bb1f4f15cabab9265016dd0272323dc6a9e85885c54022059a7b87c02861ee70662907f25ce11597d7b68d3399443a831ae40e777b76bdb",
4462                                           "304402202765b9c9ece4f127fa5407faf66da4c5ce2719cdbe47cd3175fc7d48b482e43d02205605125925e07bad1e41c618a4b434d72c88a164981c4b8af5eaf4ee9142ec3a",
4463                                           "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");
4464
4465                         test_htlc_output!(1,
4466                                           "3045022100ea9dc2a7c3c3640334dab733bb4e036e32a3106dc707b24227874fa4f7da746802204d672f7ac0fe765931a8df10b81e53a3242dd32bd9dc9331eb4a596da87954e9",
4467                                           "30440220048a41c660c4841693de037d00a407810389f4574b3286afb7bc392a438fa3f802200401d71fa87c64fe621b49ac07e3bf85157ac680acb977124da28652cc7f1a5c",
4468                                           "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");
4469                 }
4470
4471                 {
4472                         // commitment tx with three outputs untrimmed (minimum feerate)
4473                         chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
4474                         chan.feerate_per_kw = 3703;
4475
4476                         test_commitment!("30450221008b7c191dd46893b67b628e618d2dc8e81169d38bade310181ab77d7c94c6675e02203b4dd131fd7c9deb299560983dcdc485545c98f989f7ae8180c28289f9e6bdb0",
4477                                          "3044022047305531dd44391dce03ae20f8735005c615eb077a974edb0059ea1a311857d602202e0ed6972fbdd1e8cb542b06e0929bc41b2ddf236e04cb75edd56151f4197506",
4478                                          "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");
4479
4480                         assert_eq!(unsigned_tx.1.len(), 1);
4481
4482                         test_htlc_output!(0,
4483                                           "3044022044f65cf833afdcb9d18795ca93f7230005777662539815b8a601eeb3e57129a902206a4bf3e53392affbba52640627defa8dc8af61c958c9e827b2798ab45828abdd",
4484                                           "3045022100b94d931a811b32eeb885c28ddcf999ae1981893b21dd1329929543fe87ce793002206370107fdd151c5f2384f9ceb71b3107c69c74c8ed5a28a94a4ab2d27d3b0724",
4485                                           "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");
4486                 }
4487
4488                 {
4489                         // commitment tx with three outputs untrimmed (maximum feerate)
4490                         chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
4491                         chan.feerate_per_kw = 4914;
4492
4493                         test_commitment!("304402206d6cb93969d39177a09d5d45b583f34966195b77c7e585cf47ac5cce0c90cefb022031d71ae4e33a4e80df7f981d696fbdee517337806a3c7138b7491e2cbb077a0e",
4494                                          "304402206a2679efa3c7aaffd2a447fd0df7aba8792858b589750f6a1203f9259173198a022008d52a0e77a99ab533c36206cb15ad7aeb2aa72b93d4b571e728cb5ec2f6fe26",
4495                                          "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");
4496
4497                         assert_eq!(unsigned_tx.1.len(), 1);
4498
4499                         test_htlc_output!(0,
4500                                           "3045022100fcb38506bfa11c02874092a843d0cc0a8613c23b639832564a5f69020cb0f6ba02206508b9e91eaa001425c190c68ee5f887e1ad5b1b314002e74db9dbd9e42dbecf",
4501                                           "304502210086e76b460ddd3cea10525fba298405d3fe11383e56966a5091811368362f689a02200f72ee75657915e0ede89c28709acd113ede9e1b7be520e3bc5cda425ecd6e68",
4502                                           "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");
4503                 }
4504
4505                 {
4506                         // commitment tx with two outputs untrimmed (minimum feerate)
4507                         chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
4508                         chan.feerate_per_kw = 4915;
4509
4510                         test_commitment!("304402200769ba89c7330dfa4feba447b6e322305f12ac7dac70ec6ba997ed7c1b598d0802204fe8d337e7fee781f9b7b1a06e580b22f4f79d740059560191d7db53f8765552",
4511                                          "3045022100a012691ba6cea2f73fa8bac37750477e66363c6d28813b0bb6da77c8eb3fb0270220365e99c51304b0b1a6ab9ea1c8500db186693e39ec1ad5743ee231b0138384b9",
4512                                          "02000000000101bef67e4e2fb9ddeeb3461973cd4c62abb35050b1add772995b820b584a488489000000000038b02b8002c0c62d0000000000160014ccf1af2f2aabee14bb40fa3851ab2301de843110fa926a00000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e0400483045022100a012691ba6cea2f73fa8bac37750477e66363c6d28813b0bb6da77c8eb3fb0270220365e99c51304b0b1a6ab9ea1c8500db186693e39ec1ad5743ee231b0138384b90147304402200769ba89c7330dfa4feba447b6e322305f12ac7dac70ec6ba997ed7c1b598d0802204fe8d337e7fee781f9b7b1a06e580b22f4f79d740059560191d7db53f876555201475221023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb21030e9f7b623d2ccc7c9bd44d66d5ce21ce504c0acf6385a132cec6d3c39fa711c152ae3e195220");
4513
4514                         assert_eq!(unsigned_tx.1.len(), 0);
4515                 }
4516
4517                 {
4518                         // commitment tx with two outputs untrimmed (maximum feerate)
4519                         chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
4520                         chan.feerate_per_kw = 9651180;
4521
4522                         test_commitment!("3044022037f83ff00c8e5fb18ae1f918ffc24e54581775a20ff1ae719297ef066c71caa9022039c529cccd89ff6c5ed1db799614533844bd6d101da503761c45c713996e3bbd",
4523                                          "30440220514f977bf7edc442de8ce43ace9686e5ebdc0f893033f13e40fb46c8b8c6e1f90220188006227d175f5c35da0b092c57bea82537aed89f7778204dc5bacf4f29f2b9",
4524                                          "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");
4525
4526                         assert_eq!(unsigned_tx.1.len(), 0);
4527                 }
4528
4529                 {
4530                         // commitment tx with one output untrimmed (minimum feerate)
4531                         chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
4532                         chan.feerate_per_kw = 9651181;
4533
4534                         test_commitment!("3044022064901950be922e62cbe3f2ab93de2b99f37cff9fc473e73e394b27f88ef0731d02206d1dfa227527b4df44a07599289e207d6fd9cca60c0365682dcd3deaf739567e",
4535                                          "3044022031a82b51bd014915fe68928d1abf4b9885353fb896cac10c3fdd88d7f9c7f2e00220716bda819641d2c63e65d3549b6120112e1aeaf1742eed94a471488e79e206b1",
4536                                          "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");
4537
4538                         assert_eq!(unsigned_tx.1.len(), 0);
4539                 }
4540
4541                 {
4542                         // commitment tx with fee greater than funder amount
4543                         chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
4544                         chan.feerate_per_kw = 9651936;
4545
4546                         test_commitment!("3044022064901950be922e62cbe3f2ab93de2b99f37cff9fc473e73e394b27f88ef0731d02206d1dfa227527b4df44a07599289e207d6fd9cca60c0365682dcd3deaf739567e",
4547                                          "3044022031a82b51bd014915fe68928d1abf4b9885353fb896cac10c3fdd88d7f9c7f2e00220716bda819641d2c63e65d3549b6120112e1aeaf1742eed94a471488e79e206b1",
4548                                          "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");
4549
4550                         assert_eq!(unsigned_tx.1.len(), 0);
4551                 }
4552         }
4553
4554         #[test]
4555         fn test_per_commitment_secret_gen() {
4556                 // Test vectors from BOLT 3 Appendix D:
4557
4558                 let mut seed = [0; 32];
4559                 seed[0..32].clone_from_slice(&hex::decode("0000000000000000000000000000000000000000000000000000000000000000").unwrap());
4560                 assert_eq!(chan_utils::build_commitment_secret(seed, 281474976710655),
4561                            hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap()[..]);
4562
4563                 seed[0..32].clone_from_slice(&hex::decode("FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF").unwrap());
4564                 assert_eq!(chan_utils::build_commitment_secret(seed, 281474976710655),
4565                            hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap()[..]);
4566
4567                 assert_eq!(chan_utils::build_commitment_secret(seed, 0xaaaaaaaaaaa),
4568                            hex::decode("56f4008fb007ca9acf0e15b054d5c9fd12ee06cea347914ddbaed70d1c13a528").unwrap()[..]);
4569
4570                 assert_eq!(chan_utils::build_commitment_secret(seed, 0x555555555555),
4571                            hex::decode("9015daaeb06dba4ccc05b91b2f73bd54405f2be9f217fbacd3c5ac2e62327d31").unwrap()[..]);
4572
4573                 seed[0..32].clone_from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap());
4574                 assert_eq!(chan_utils::build_commitment_secret(seed, 1),
4575                            hex::decode("915c75942a26bb3a433a8ce2cb0427c29ec6c1775cfc78328b57f6ba7bfeaa9c").unwrap()[..]);
4576         }
4577
4578         #[test]
4579         fn test_key_derivation() {
4580                 // Test vectors from BOLT 3 Appendix E:
4581                 let secp_ctx = Secp256k1::new();
4582
4583                 let base_secret = SecretKey::from_slice(&hex::decode("000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f").unwrap()[..]).unwrap();
4584                 let per_commitment_secret = SecretKey::from_slice(&hex::decode("1f1e1d1c1b1a191817161514131211100f0e0d0c0b0a09080706050403020100").unwrap()[..]).unwrap();
4585
4586                 let base_point = PublicKey::from_secret_key(&secp_ctx, &base_secret);
4587                 assert_eq!(base_point.serialize()[..], hex::decode("036d6caac248af96f6afa7f904f550253a0f3ef3f5aa2fe6838a95b216691468e2").unwrap()[..]);
4588
4589                 let per_commitment_point = PublicKey::from_secret_key(&secp_ctx, &per_commitment_secret);
4590                 assert_eq!(per_commitment_point.serialize()[..], hex::decode("025f7117a78150fe2ef97db7cfc83bd57b2e2c0d0dd25eaf467a4a1c2a45ce1486").unwrap()[..]);
4591
4592                 assert_eq!(chan_utils::derive_public_key(&secp_ctx, &per_commitment_point, &base_point).unwrap().serialize()[..],
4593                                 hex::decode("0235f2dbfaa89b57ec7b055afe29849ef7ddfeb1cefdb9ebdc43f5494984db29e5").unwrap()[..]);
4594
4595                 assert_eq!(chan_utils::derive_private_key(&secp_ctx, &per_commitment_point, &base_secret).unwrap(),
4596                                 SecretKey::from_slice(&hex::decode("cbced912d3b21bf196a766651e436aff192362621ce317704ea2f75d87e7be0f").unwrap()[..]).unwrap());
4597
4598                 assert_eq!(chan_utils::derive_public_revocation_key(&secp_ctx, &per_commitment_point, &base_point).unwrap().serialize()[..],
4599                                 hex::decode("02916e326636d19c33f13e8c0c3a03dd157f332f3e99c317c141dd865eb01f8ff0").unwrap()[..]);
4600
4601                 assert_eq!(chan_utils::derive_private_revocation_key(&secp_ctx, &per_commitment_secret, &base_secret).unwrap(),
4602                                 SecretKey::from_slice(&hex::decode("d09ffff62ddb2297ab000cc85bcb4283fdeb6aa052affbc9dddcf33b61078110").unwrap()[..]).unwrap());
4603         }
4604 }