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

   1 //! The top-level channel management and payment tracking stuff lives here.
   2 //!
   3 //! The ChannelManager is the main chunk of logic implementing the lightning protocol and is
   4 //! responsible for tracking which channels are open, HTLCs are in flight and reestablishing those
   5 //! upon reconnect to the relevant peer(s).
   6 //!
   7 //! It does not manage routing logic (see ln::router for that) nor does it manage constructing
   8 //! on-chain transactions (it only monitors the chain to watch for any force-closes that might
   9 //! imply it needs to fail HTLCs/payments/channels it manages).
  10
  11 use bitcoin::blockdata::block::BlockHeader;
  12 use bitcoin::blockdata::transaction::Transaction;
  13 use bitcoin::blockdata::constants::genesis_block;
  14 use bitcoin::network::constants::Network;
  15 use bitcoin::util::hash::BitcoinHash;
  16
  17 use bitcoin_hashes::{Hash, HashEngine};
  18 use bitcoin_hashes::hmac::{Hmac, HmacEngine};
  19 use bitcoin_hashes::sha256::Hash as Sha256;
  20 use bitcoin_hashes::sha256d::Hash as Sha256dHash;
  21 use bitcoin_hashes::cmp::fixed_time_eq;
  22
  23 use secp256k1::key::{SecretKey,PublicKey};
  24 use secp256k1::Secp256k1;
  25 use secp256k1::ecdh::SharedSecret;
  26 use secp256k1;
  27
  28 use chain::chaininterface::{BroadcasterInterface,ChainListener,FeeEstimator};
  29 use chain::transaction::OutPoint;
  30 use ln::channel::{Channel, ChannelError};
  31 use ln::channelmonitor::{ChannelMonitor, ChannelMonitorUpdateErr, ManyChannelMonitor, CLTV_CLAIM_BUFFER, LATENCY_GRACE_PERIOD_BLOCKS, ANTI_REORG_DELAY};
  32 use ln::router::Route;
  33 use ln::features::InitFeatures;
  34 use ln::msgs;
  35 use ln::onion_utils;
  36 use ln::msgs::{ChannelMessageHandler, DecodeError, LightningError};
  37 use chain::keysinterface::{ChannelKeys, KeysInterface, KeysManager, InMemoryChannelKeys};
  38 use util::config::UserConfig;
  39 use util::{byte_utils, events};
  40 use util::ser::{Readable, ReadableArgs, Writeable, Writer};
  41 use util::chacha20::{ChaCha20, ChaChaReader};
  42 use util::logger::Logger;
  43 use util::errors::APIError;
  44
  45 use std::{cmp, mem};
  46 use std::collections::{HashMap, hash_map, HashSet};
  47 use std::io::{Cursor, Read};
  48 use std::sync::{Arc, Mutex, MutexGuard, RwLock};
  49 use std::sync::atomic::{AtomicUsize, Ordering};
  50 use std::time::Duration;
  51 use std::marker::{Sync, Send};
  52 use std::ops::Deref;
  53
  54 // We hold various information about HTLC relay in the HTLC objects in Channel itself:
  55 //
  56 // Upon receipt of an HTLC from a peer, we'll give it a PendingHTLCStatus indicating if it should
  57 // forward the HTLC with information it will give back to us when it does so, or if it should Fail
  58 // the HTLC with the relevant message for the Channel to handle giving to the remote peer.
  59 //
  60 // Once said HTLC is committed in the Channel, if the PendingHTLCStatus indicated Forward, the
  61 // Channel will return the PendingHTLCInfo back to us, and we will create an HTLCForwardInfo
  62 // with it to track where it came from (in case of onwards-forward error), waiting a random delay
  63 // before we forward it.
  64 //
  65 // We will then use HTLCForwardInfo's PendingHTLCInfo to construct an outbound HTLC, with a
  66 // relevant HTLCSource::PreviousHopData filled in to indicate where it came from (which we can use
  67 // to either fail-backwards or fulfill the HTLC backwards along the relevant path).
  68 // Alternatively, we can fill an outbound HTLC with a HTLCSource::OutboundRoute indicating this is
  69 // our payment, which we can use to decode errors or inform the user that the payment was sent.
  70
  71 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
  72 pub(super) struct PendingHTLCInfo {
  73         onion_packet: Option<msgs::OnionPacket>,
  74         incoming_shared_secret: [u8; 32],
  75         payment_hash: PaymentHash,
  76         short_channel_id: u64,
  77         pub(super) amt_to_forward: u64,
  78         pub(super) outgoing_cltv_value: u32,
  79 }
  80
  81 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
  82 pub(super) enum HTLCFailureMsg {
  83         Relay(msgs::UpdateFailHTLC),
  84         Malformed(msgs::UpdateFailMalformedHTLC),
  85 }
  86
  87 /// Stores whether we can't forward an HTLC or relevant forwarding info
  88 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
  89 pub(super) enum PendingHTLCStatus {
  90         Forward(PendingHTLCInfo),
  91         Fail(HTLCFailureMsg),
  92 }
  93
  94 pub(super) enum HTLCForwardInfo {
  95         AddHTLC {
  96                 prev_short_channel_id: u64,
  97                 prev_htlc_id: u64,
  98                 forward_info: PendingHTLCInfo,
  99         },
 100         FailHTLC {
 101                 htlc_id: u64,
 102                 err_packet: msgs::OnionErrorPacket,
 103         },
 104 }
 105
 106 /// Tracks the inbound corresponding to an outbound HTLC
 107 #[derive(Clone, PartialEq)]
 108 pub(super) struct HTLCPreviousHopData {
 109         short_channel_id: u64,
 110         htlc_id: u64,
 111         incoming_packet_shared_secret: [u8; 32],
 112 }
 113
 114 /// Tracks the inbound corresponding to an outbound HTLC
 115 #[derive(Clone, PartialEq)]
 116 pub(super) enum HTLCSource {
 117         PreviousHopData(HTLCPreviousHopData),
 118         OutboundRoute {
 119                 route: Route,
 120                 session_priv: SecretKey,
 121                 /// Technically we can recalculate this from the route, but we cache it here to avoid
 122                 /// doing a double-pass on route when we get a failure back
 123                 first_hop_htlc_msat: u64,
 124         },
 125 }
 126 #[cfg(test)]
 127 impl HTLCSource {
 128         pub fn dummy() -> Self {
 129                 HTLCSource::OutboundRoute {
 130                         route: Route { hops: Vec::new() },
 131                         session_priv: SecretKey::from_slice(&[1; 32]).unwrap(),
 132                         first_hop_htlc_msat: 0,
 133                 }
 134         }
 135 }
 136
 137 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
 138 pub(super) enum HTLCFailReason {
 139         LightningError {
 140                 err: msgs::OnionErrorPacket,
 141         },
 142         Reason {
 143                 failure_code: u16,
 144                 data: Vec<u8>,
 145         }
 146 }
 147
 148 /// payment_hash type, use to cross-lock hop
 149 #[derive(Hash, Copy, Clone, PartialEq, Eq, Debug)]
 150 pub struct PaymentHash(pub [u8;32]);
 151 /// payment_preimage type, use to route payment between hop
 152 #[derive(Hash, Copy, Clone, PartialEq, Eq, Debug)]
 153 pub struct PaymentPreimage(pub [u8;32]);
 154
 155 type ShutdownResult = (Vec<Transaction>, Vec<(HTLCSource, PaymentHash)>);
 156
 157 /// Error type returned across the channel_state mutex boundary. When an Err is generated for a
 158 /// Channel, we generally end up with a ChannelError::Close for which we have to close the channel
 159 /// immediately (ie with no further calls on it made). Thus, this step happens inside a
 160 /// channel_state lock. We then return the set of things that need to be done outside the lock in
 161 /// this struct and call handle_error!() on it.
 162
 163 struct MsgHandleErrInternal {
 164         err: msgs::LightningError,
 165         shutdown_finish: Option<(ShutdownResult, Option<msgs::ChannelUpdate>)>,
 166 }
 167 impl MsgHandleErrInternal {
 168         #[inline]
 169         fn send_err_msg_no_close(err: &'static str, channel_id: [u8; 32]) -> Self {
 170                 Self {
 171                         err: LightningError {
 172                                 err,
 173                                 action: msgs::ErrorAction::SendErrorMessage {
 174                                         msg: msgs::ErrorMessage {
 175                                                 channel_id,
 176                                                 data: err.to_string()
 177                                         },
 178                                 },
 179                         },
 180                         shutdown_finish: None,
 181                 }
 182         }
 183         #[inline]
 184         fn ignore_no_close(err: &'static str) -> Self {
 185                 Self {
 186                         err: LightningError {
 187                                 err,
 188                                 action: msgs::ErrorAction::IgnoreError,
 189                         },
 190                         shutdown_finish: None,
 191                 }
 192         }
 193         #[inline]
 194         fn from_no_close(err: msgs::LightningError) -> Self {
 195                 Self { err, shutdown_finish: None }
 196         }
 197         #[inline]
 198         fn from_finish_shutdown(err: &'static str, channel_id: [u8; 32], shutdown_res: ShutdownResult, channel_update: Option<msgs::ChannelUpdate>) -> Self {
 199                 Self {
 200                         err: LightningError {
 201                                 err,
 202                                 action: msgs::ErrorAction::SendErrorMessage {
 203                                         msg: msgs::ErrorMessage {
 204                                                 channel_id,
 205                                                 data: err.to_string()
 206                                         },
 207                                 },
 208                         },
 209                         shutdown_finish: Some((shutdown_res, channel_update)),
 210                 }
 211         }
 212         #[inline]
 213         fn from_chan_no_close(err: ChannelError, channel_id: [u8; 32]) -> Self {
 214                 Self {
 215                         err: match err {
 216                                 ChannelError::Ignore(msg) => LightningError {
 217                                         err: msg,
 218                                         action: msgs::ErrorAction::IgnoreError,
 219                                 },
 220                                 ChannelError::Close(msg) => LightningError {
 221                                         err: msg,
 222                                         action: msgs::ErrorAction::SendErrorMessage {
 223                                                 msg: msgs::ErrorMessage {
 224                                                         channel_id,
 225                                                         data: msg.to_string()
 226                                                 },
 227                                         },
 228                                 },
 229                                 ChannelError::CloseDelayBroadcast { msg, .. } => LightningError {
 230                                         err: msg,
 231                                         action: msgs::ErrorAction::SendErrorMessage {
 232                                                 msg: msgs::ErrorMessage {
 233                                                         channel_id,
 234                                                         data: msg.to_string()
 235                                                 },
 236                                         },
 237                                 },
 238                         },
 239                         shutdown_finish: None,
 240                 }
 241         }
 242 }
 243
 244 /// We hold back HTLCs we intend to relay for a random interval greater than this (see
 245 /// Event::PendingHTLCsForwardable for the API guidelines indicating how long should be waited).
 246 /// This provides some limited amount of privacy. Ideally this would range from somewhere like one
 247 /// second to 30 seconds, but people expect lightning to be, you know, kinda fast, sadly.
 248 const MIN_HTLC_RELAY_HOLDING_CELL_MILLIS: u64 = 100;
 249
 250 /// For events which result in both a RevokeAndACK and a CommitmentUpdate, by default they should
 251 /// be sent in the order they appear in the return value, however sometimes the order needs to be
 252 /// variable at runtime (eg Channel::channel_reestablish needs to re-send messages in the order
 253 /// they were originally sent). In those cases, this enum is also returned.
 254 #[derive(Clone, PartialEq)]
 255 pub(super) enum RAACommitmentOrder {
 256         /// Send the CommitmentUpdate messages first
 257         CommitmentFirst,
 258         /// Send the RevokeAndACK message first
 259         RevokeAndACKFirst,
 260 }
 261
 262 // Note this is only exposed in cfg(test):
 263 pub(super) struct ChannelHolder<ChanSigner: ChannelKeys> {
 264         pub(super) by_id: HashMap<[u8; 32], Channel<ChanSigner>>,
 265         pub(super) short_to_id: HashMap<u64, [u8; 32]>,
 266         /// short channel id -> forward infos. Key of 0 means payments received
 267         /// Note that while this is held in the same mutex as the channels themselves, no consistency
 268         /// guarantees are made about the existence of a channel with the short id here, nor the short
 269         /// ids in the PendingHTLCInfo!
 270         pub(super) forward_htlcs: HashMap<u64, Vec<HTLCForwardInfo>>,
 271         /// payment_hash -> Vec<(amount_received, htlc_source)> for tracking things that were to us and
 272         /// can be failed/claimed by the user
 273         /// Note that while this is held in the same mutex as the channels themselves, no consistency
 274         /// guarantees are made about the channels given here actually existing anymore by the time you
 275         /// go to read them!
 276         pub(super) claimable_htlcs: HashMap<PaymentHash, Vec<(u64, HTLCPreviousHopData)>>,
 277         /// Messages to send to peers - pushed to in the same lock that they are generated in (except
 278         /// for broadcast messages, where ordering isn't as strict).
 279         pub(super) pending_msg_events: Vec<events::MessageSendEvent>,
 280 }
 281
 282 /// State we hold per-peer. In the future we should put channels in here, but for now we only hold
 283 /// the latest Init features we heard from the peer.
 284 struct PeerState {
 285         latest_features: InitFeatures,
 286 }
 287
 288 #[cfg(not(any(target_pointer_width = "32", target_pointer_width = "64")))]
 289 const ERR: () = "You need at least 32 bit pointers (well, usize, but we'll assume they're the same) for ChannelManager::latest_block_height";
 290
 291 /// SimpleArcChannelManager is useful when you need a ChannelManager with a static lifetime, e.g.
 292 /// when you're using lightning-net-tokio (since tokio::spawn requires parameters with static
 293 /// lifetimes). Other times you can afford a reference, which is more efficient, in which case
 294 /// SimpleRefChannelManager is the more appropriate type. Defining these type aliases prevents
 295 /// issues such as overly long function definitions. Note that the ChannelManager can take any
 296 /// type that implements KeysInterface for its keys manager, but this type alias chooses the
 297 /// concrete type of the KeysManager.
 298 pub type SimpleArcChannelManager<M, T, F> = Arc<ChannelManager<InMemoryChannelKeys, Arc<M>, Arc<T>, Arc<KeysManager>, Arc<F>>>;
 299
 300 /// SimpleRefChannelManager is a type alias for a ChannelManager reference, and is the reference
 301 /// counterpart to the SimpleArcChannelManager type alias. Use this type by default when you don't
 302 /// need a ChannelManager with a static lifetime. You'll need a static lifetime in cases such as
 303 /// usage of lightning-net-tokio (since tokio::spawn requires parameters with static lifetimes).
 304 /// But if this is not necessary, using a reference is more efficient. Defining these type aliases
 305 /// helps with issues such as long function definitions. Note that the ChannelManager can take any
 306 /// type that implements KeysInterface for its keys manager, but this type alias chooses the
 307 /// concrete type of the KeysManager.
 308 pub type SimpleRefChannelManager<'a, 'b, 'c, 'd, M, T, F> = ChannelManager<InMemoryChannelKeys, &'a M, &'b T, &'c KeysManager, &'d F>;
 309
 310 /// Manager which keeps track of a number of channels and sends messages to the appropriate
 311 /// channel, also tracking HTLC preimages and forwarding onion packets appropriately.
 312 ///
 313 /// Implements ChannelMessageHandler, handling the multi-channel parts and passing things through
 314 /// to individual Channels.
 315 ///
 316 /// Implements Writeable to write out all channel state to disk. Implies peer_disconnected() for
 317 /// all peers during write/read (though does not modify this instance, only the instance being
 318 /// serialized). This will result in any channels which have not yet exchanged funding_created (ie
 319 /// called funding_transaction_generated for outbound channels).
 320 ///
 321 /// Note that you can be a bit lazier about writing out ChannelManager than you can be with
 322 /// ChannelMonitors. With ChannelMonitors you MUST write each monitor update out to disk before
 323 /// returning from ManyChannelMonitor::add_/update_monitor, with ChannelManagers, writing updates
 324 /// happens out-of-band (and will prevent any other ChannelManager operations from occurring during
 325 /// the serialization process). If the deserialized version is out-of-date compared to the
 326 /// ChannelMonitors passed by reference to read(), those channels will be force-closed based on the
 327 /// ChannelMonitor state and no funds will be lost (mod on-chain transaction fees).
 328 ///
 329 /// Note that the deserializer is only implemented for (Sha256dHash, ChannelManager), which
 330 /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
 331 /// the "reorg path" (ie call block_disconnected() until you get to a common block and then call
 332 /// block_connected() to step towards your best block) upon deserialization before using the
 333 /// object!
 334 ///
 335 /// Note that ChannelManager is responsible for tracking liveness of its channels and generating
 336 /// ChannelUpdate messages informing peers that the channel is temporarily disabled. To avoid
 337 /// spam due to quick disconnection/reconnection, updates are not sent until the channel has been
 338 /// offline for a full minute. In order to track this, you must call
 339 /// timer_chan_freshness_every_min roughly once per minute, though it doesn't have to be perfect.
 340 ///
 341 /// Rather than using a plain ChannelManager, it is preferable to use either a SimpleArcChannelManager
 342 /// a SimpleRefChannelManager, for conciseness. See their documentation for more details, but
 343 /// essentially you should default to using a SimpleRefChannelManager, and use a
 344 /// SimpleArcChannelManager when you require a ChannelManager with a static lifetime, such as when
 345 /// you're using lightning-net-tokio.
 346 pub struct ChannelManager<ChanSigner: ChannelKeys, M: Deref, T: Deref, K: Deref, F: Deref>
 347         where M::Target: ManyChannelMonitor<ChanSigner>,
 348         T::Target: BroadcasterInterface,
 349         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
 350         F::Target: FeeEstimator,
 351 {
 352         default_configuration: UserConfig,
 353         genesis_hash: Sha256dHash,
 354         fee_estimator: F,
 355         monitor: M,
 356         tx_broadcaster: T,
 357
 358         #[cfg(test)]
 359         pub(super) latest_block_height: AtomicUsize,
 360         #[cfg(not(test))]
 361         latest_block_height: AtomicUsize,
 362         last_block_hash: Mutex<Sha256dHash>,
 363         secp_ctx: Secp256k1<secp256k1::All>,
 364
 365         #[cfg(test)]
 366         pub(super) channel_state: Mutex<ChannelHolder<ChanSigner>>,
 367         #[cfg(not(test))]
 368         channel_state: Mutex<ChannelHolder<ChanSigner>>,
 369         our_network_key: SecretKey,
 370
 371         /// The bulk of our storage will eventually be here (channels and message queues and the like).
 372         /// If we are connected to a peer we always at least have an entry here, even if no channels
 373         /// are currently open with that peer.
 374         /// Because adding or removing an entry is rare, we usually take an outer read lock and then
 375         /// operate on the inner value freely. Sadly, this prevents parallel operation when opening a
 376         /// new channel.
 377         per_peer_state: RwLock<HashMap<PublicKey, Mutex<PeerState>>>,
 378
 379         pending_events: Mutex<Vec<events::Event>>,
 380         /// Used when we have to take a BIG lock to make sure everything is self-consistent.
 381         /// Essentially just when we're serializing ourselves out.
 382         /// Taken first everywhere where we are making changes before any other locks.
 383         total_consistency_lock: RwLock<()>,
 384
 385         keys_manager: K,
 386
 387         logger: Arc<Logger>,
 388 }
 389
 390 /// The amount of time we require our counterparty wait to claim their money (ie time between when
 391 /// we, or our watchtower, must check for them having broadcast a theft transaction).
 392 pub(crate) const BREAKDOWN_TIMEOUT: u16 = 6 * 24;
 393 /// The amount of time we're willing to wait to claim money back to us
 394 pub(crate) const MAX_LOCAL_BREAKDOWN_TIMEOUT: u16 = 6 * 24 * 7;
 395
 396 /// The minimum number of blocks between an inbound HTLC's CLTV and the corresponding outbound
 397 /// HTLC's CLTV. This should always be a few blocks greater than channelmonitor::CLTV_CLAIM_BUFFER,
 398 /// ie the node we forwarded the payment on to should always have enough room to reliably time out
 399 /// the HTLC via a full update_fail_htlc/commitment_signed dance before we hit the
 400 /// CLTV_CLAIM_BUFFER point (we static assert that it's at least 3 blocks more).
 401 const CLTV_EXPIRY_DELTA: u16 = 6 * 12; //TODO?
 402 pub(super) const CLTV_FAR_FAR_AWAY: u32 = 6 * 24 * 7; //TODO?
 403
 404 // Check that our CLTV_EXPIRY is at least CLTV_CLAIM_BUFFER + ANTI_REORG_DELAY + LATENCY_GRACE_PERIOD_BLOCKS,
 405 // ie that if the next-hop peer fails the HTLC within
 406 // LATENCY_GRACE_PERIOD_BLOCKS then we'll still have CLTV_CLAIM_BUFFER left to timeout it onchain,
 407 // then waiting ANTI_REORG_DELAY to be reorg-safe on the outbound HLTC and
 408 // failing the corresponding htlc backward, and us now seeing the last block of ANTI_REORG_DELAY before
 409 // LATENCY_GRACE_PERIOD_BLOCKS.
 410 #[deny(const_err)]
 411 #[allow(dead_code)]
 412 const CHECK_CLTV_EXPIRY_SANITY: u32 = CLTV_EXPIRY_DELTA as u32 - LATENCY_GRACE_PERIOD_BLOCKS - CLTV_CLAIM_BUFFER - ANTI_REORG_DELAY - LATENCY_GRACE_PERIOD_BLOCKS;
 413
 414 // Check for ability of an attacker to make us fail on-chain by delaying inbound claim. See
 415 // ChannelMontior::would_broadcast_at_height for a description of why this is needed.
 416 #[deny(const_err)]
 417 #[allow(dead_code)]
 418 const CHECK_CLTV_EXPIRY_SANITY_2: u32 = CLTV_EXPIRY_DELTA as u32 - LATENCY_GRACE_PERIOD_BLOCKS - 2*CLTV_CLAIM_BUFFER;
 419
 420 macro_rules! secp_call {
 421         ( $res: expr, $err: expr ) => {
 422                 match $res {
 423                         Ok(key) => key,
 424                         Err(_) => return Err($err),
 425                 }
 426         };
 427 }
 428
 429 /// Details of a channel, as returned by ChannelManager::list_channels and ChannelManager::list_usable_channels
 430 pub struct ChannelDetails {
 431         /// The channel's ID (prior to funding transaction generation, this is a random 32 bytes,
 432         /// thereafter this is the txid of the funding transaction xor the funding transaction output).
 433         /// Note that this means this value is *not* persistent - it can change once during the
 434         /// lifetime of the channel.
 435         pub channel_id: [u8; 32],
 436         /// The position of the funding transaction in the chain. None if the funding transaction has
 437         /// not yet been confirmed and the channel fully opened.
 438         pub short_channel_id: Option<u64>,
 439         /// The node_id of our counterparty
 440         pub remote_network_id: PublicKey,
 441         /// The Features the channel counterparty provided upon last connection.
 442         /// Useful for routing as it is the most up-to-date copy of the counterparty's features and
 443         /// many routing-relevant features are present in the init context.
 444         pub counterparty_features: InitFeatures,
 445         /// The value, in satoshis, of this channel as appears in the funding output
 446         pub channel_value_satoshis: u64,
 447         /// The user_id passed in to create_channel, or 0 if the channel was inbound.
 448         pub user_id: u64,
 449         /// The available outbound capacity for sending HTLCs to the remote peer. This does not include
 450         /// any pending HTLCs which are not yet fully resolved (and, thus, who's balance is not
 451         /// available for inclusion in new outbound HTLCs). This further does not include any pending
 452         /// outgoing HTLCs which are awaiting some other resolution to be sent.
 453         pub outbound_capacity_msat: u64,
 454         /// The available inbound capacity for the remote peer to send HTLCs to us. This does not
 455         /// include any pending HTLCs which are not yet fully resolved (and, thus, who's balance is not
 456         /// available for inclusion in new inbound HTLCs).
 457         /// Note that there are some corner cases not fully handled here, so the actual available
 458         /// inbound capacity may be slightly higher than this.
 459         pub inbound_capacity_msat: u64,
 460         /// True if the channel is (a) confirmed and funding_locked messages have been exchanged, (b)
 461         /// the peer is connected, and (c) no monitor update failure is pending resolution.
 462         pub is_live: bool,
 463 }
 464
 465 macro_rules! handle_error {
 466         ($self: ident, $internal: expr, $their_node_id: expr, $locked_channel_state: expr) => {
 467                 match $internal {
 468                         Ok(msg) => Ok(msg),
 469                         Err(MsgHandleErrInternal { err, shutdown_finish }) => {
 470                                 if let Some((shutdown_res, update_option)) = shutdown_finish {
 471                                         $self.finish_force_close_channel(shutdown_res);
 472                                         if let Some(update) = update_option {
 473                                                 $locked_channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
 474                                                         msg: update
 475                                                 });
 476                                         }
 477                                 }
 478                                 log_error!($self, "{}", err.err);
 479                                 if let msgs::ErrorAction::IgnoreError = err.action {
 480                                 } else { $locked_channel_state.pending_msg_events.push(events::MessageSendEvent::HandleError { node_id: $their_node_id, action: err.action.clone() }); }
 481                                 // Return error in case higher-API need one
 482                                 Err(err)
 483                         },
 484                 }
 485         }
 486 }
 487
 488 macro_rules! break_chan_entry {
 489         ($self: ident, $res: expr, $channel_state: expr, $entry: expr) => {
 490                 match $res {
 491                         Ok(res) => res,
 492                         Err(ChannelError::Ignore(msg)) => {
 493                                 break Err(MsgHandleErrInternal::from_chan_no_close(ChannelError::Ignore(msg), $entry.key().clone()))
 494                         },
 495                         Err(ChannelError::Close(msg)) => {
 496                                 log_trace!($self, "Closing channel {} due to Close-required error: {}", log_bytes!($entry.key()[..]), msg);
 497                                 let (channel_id, mut chan) = $entry.remove_entry();
 498                                 if let Some(short_id) = chan.get_short_channel_id() {
 499                                         $channel_state.short_to_id.remove(&short_id);
 500                                 }
 501                                 break Err(MsgHandleErrInternal::from_finish_shutdown(msg, channel_id, chan.force_shutdown(), $self.get_channel_update(&chan).ok()))
 502                         },
 503                         Err(ChannelError::CloseDelayBroadcast { .. }) => { panic!("Wait is only generated on receipt of channel_reestablish, which is handled by try_chan_entry, we don't bother to support it here"); }
 504                 }
 505         }
 506 }
 507
 508 macro_rules! try_chan_entry {
 509         ($self: ident, $res: expr, $channel_state: expr, $entry: expr) => {
 510                 match $res {
 511                         Ok(res) => res,
 512                         Err(ChannelError::Ignore(msg)) => {
 513                                 return Err(MsgHandleErrInternal::from_chan_no_close(ChannelError::Ignore(msg), $entry.key().clone()))
 514                         },
 515                         Err(ChannelError::Close(msg)) => {
 516                                 log_trace!($self, "Closing channel {} due to Close-required error: {}", log_bytes!($entry.key()[..]), msg);
 517                                 let (channel_id, mut chan) = $entry.remove_entry();
 518                                 if let Some(short_id) = chan.get_short_channel_id() {
 519                                         $channel_state.short_to_id.remove(&short_id);
 520                                 }
 521                                 return Err(MsgHandleErrInternal::from_finish_shutdown(msg, channel_id, chan.force_shutdown(), $self.get_channel_update(&chan).ok()))
 522                         },
 523                         Err(ChannelError::CloseDelayBroadcast { msg, update }) => {
 524                                 log_error!($self, "Channel {} need to be shutdown but closing transactions not broadcast due to {}", log_bytes!($entry.key()[..]), msg);
 525                                 let (channel_id, mut chan) = $entry.remove_entry();
 526                                 if let Some(short_id) = chan.get_short_channel_id() {
 527                                         $channel_state.short_to_id.remove(&short_id);
 528                                 }
 529                                 if let Err(e) = $self.monitor.update_monitor(chan.get_funding_txo().unwrap(), update) {
 530                                         match e {
 531                                                 // Upstream channel is dead, but we want at least to fail backward HTLCs to save
 532                                                 // downstream channels. In case of PermanentFailure, we are not going to be able
 533                                                 // to claim back to_remote output on remote commitment transaction. Doesn't
 534                                                 // make a difference here, we are concern about HTLCs circuit, not onchain funds.
 535                                                 ChannelMonitorUpdateErr::PermanentFailure => {},
 536                                                 ChannelMonitorUpdateErr::TemporaryFailure => {},
 537                                         }
 538                                 }
 539                                 let mut shutdown_res = chan.force_shutdown();
 540                                 if shutdown_res.0.len() >= 1 {
 541                                         log_error!($self, "You have a toxic local commitment transaction {} avaible in channel monitor, read comment in ChannelMonitor::get_latest_local_commitment_txn to be informed of manual action to take", shutdown_res.0[0].txid());
 542                                 }
 543                                 shutdown_res.0.clear();
 544                                 return Err(MsgHandleErrInternal::from_finish_shutdown(msg, channel_id, shutdown_res, $self.get_channel_update(&chan).ok()))
 545                         }
 546                 }
 547         }
 548 }
 549
 550 macro_rules! handle_monitor_err {
 551         ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $resend_raa: expr, $resend_commitment: expr) => {
 552                 handle_monitor_err!($self, $err, $channel_state, $entry, $action_type, $resend_raa, $resend_commitment, Vec::new(), Vec::new())
 553         };
 554         ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $resend_raa: expr, $resend_commitment: expr, $failed_forwards: expr, $failed_fails: expr) => {
 555                 match $err {
 556                         ChannelMonitorUpdateErr::PermanentFailure => {
 557                                 log_error!($self, "Closing channel {} due to monitor update PermanentFailure", log_bytes!($entry.key()[..]));
 558                                 let (channel_id, mut chan) = $entry.remove_entry();
 559                                 if let Some(short_id) = chan.get_short_channel_id() {
 560                                         $channel_state.short_to_id.remove(&short_id);
 561                                 }
 562                                 // TODO: $failed_fails is dropped here, which will cause other channels to hit the
 563                                 // chain in a confused state! We need to move them into the ChannelMonitor which
 564                                 // will be responsible for failing backwards once things confirm on-chain.
 565                                 // It's ok that we drop $failed_forwards here - at this point we'd rather they
 566                                 // broadcast HTLC-Timeout and pay the associated fees to get their funds back than
 567                                 // us bother trying to claim it just to forward on to another peer. If we're
 568                                 // splitting hairs we'd prefer to claim payments that were to us, but we haven't
 569                                 // given up the preimage yet, so might as well just wait until the payment is
 570                                 // retried, avoiding the on-chain fees.
 571                                 let res: Result<(), _> = Err(MsgHandleErrInternal::from_finish_shutdown("ChannelMonitor storage failure", channel_id, chan.force_shutdown(), $self.get_channel_update(&chan).ok()));
 572                                 res
 573                         },
 574                         ChannelMonitorUpdateErr::TemporaryFailure => {
 575                                 log_info!($self, "Disabling channel {} due to monitor update TemporaryFailure. On restore will send {} and process {} forwards and {} fails",
 576                                                 log_bytes!($entry.key()[..]),
 577                                                 if $resend_commitment && $resend_raa {
 578                                                                 match $action_type {
 579                                                                         RAACommitmentOrder::CommitmentFirst => { "commitment then RAA" },
 580                                                                         RAACommitmentOrder::RevokeAndACKFirst => { "RAA then commitment" },
 581                                                                 }
 582                                                         } else if $resend_commitment { "commitment" }
 583                                                         else if $resend_raa { "RAA" }
 584                                                         else { "nothing" },
 585                                                 (&$failed_forwards as &Vec<(PendingHTLCInfo, u64)>).len(),
 586                                                 (&$failed_fails as &Vec<(HTLCSource, PaymentHash, HTLCFailReason)>).len());
 587                                 if !$resend_commitment {
 588                                         debug_assert!($action_type == RAACommitmentOrder::RevokeAndACKFirst || !$resend_raa);
 589                                 }
 590                                 if !$resend_raa {
 591                                         debug_assert!($action_type == RAACommitmentOrder::CommitmentFirst || !$resend_commitment);
 592                                 }
 593                                 $entry.get_mut().monitor_update_failed($resend_raa, $resend_commitment, $failed_forwards, $failed_fails);
 594                                 Err(MsgHandleErrInternal::from_chan_no_close(ChannelError::Ignore("Failed to update ChannelMonitor"), *$entry.key()))
 595                         },
 596                 }
 597         }
 598 }
 599
 600 macro_rules! return_monitor_err {
 601         ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $resend_raa: expr, $resend_commitment: expr) => {
 602                 return handle_monitor_err!($self, $err, $channel_state, $entry, $action_type, $resend_raa, $resend_commitment);
 603         };
 604         ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $resend_raa: expr, $resend_commitment: expr, $failed_forwards: expr, $failed_fails: expr) => {
 605                 return handle_monitor_err!($self, $err, $channel_state, $entry, $action_type, $resend_raa, $resend_commitment, $failed_forwards, $failed_fails);
 606         }
 607 }
 608
 609 // Does not break in case of TemporaryFailure!
 610 macro_rules! maybe_break_monitor_err {
 611         ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $resend_raa: expr, $resend_commitment: expr) => {
 612                 match (handle_monitor_err!($self, $err, $channel_state, $entry, $action_type, $resend_raa, $resend_commitment), $err) {
 613                         (e, ChannelMonitorUpdateErr::PermanentFailure) => {
 614                                 break e;
 615                         },
 616                         (_, ChannelMonitorUpdateErr::TemporaryFailure) => { },
 617                 }
 618         }
 619 }
 620
 621 impl<ChanSigner: ChannelKeys, M: Deref, T: Deref, K: Deref, F: Deref> ChannelManager<ChanSigner, M, T, K, F>
 622         where M::Target: ManyChannelMonitor<ChanSigner>,
 623         T::Target: BroadcasterInterface,
 624         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
 625         F::Target: FeeEstimator,
 626 {
 627         /// Constructs a new ChannelManager to hold several channels and route between them.
 628         ///
 629         /// This is the main "logic hub" for all channel-related actions, and implements
 630         /// ChannelMessageHandler.
 631         ///
 632         /// Non-proportional fees are fixed according to our risk using the provided fee estimator.
 633         ///
 634         /// panics if channel_value_satoshis is >= `MAX_FUNDING_SATOSHIS`!
 635         ///
 636         /// Users must provide the current blockchain height from which to track onchain channel
 637         /// funding outpoints and send payments with reliable timelocks.
 638         ///
 639         /// Users need to notify the new ChannelManager when a new block is connected or
 640         /// disconnected using its `block_connected` and `block_disconnected` methods.
 641         /// However, rather than calling these methods directly, the user should register
 642         /// the ChannelManager as a listener to the BlockNotifier and call the BlockNotifier's
 643         /// `block_(dis)connected` methods, which will notify all registered listeners in one
 644         /// go.
 645         pub fn new(network: Network, fee_est: F, monitor: M, tx_broadcaster: T, logger: Arc<Logger>, keys_manager: K, config: UserConfig, current_blockchain_height: usize) -> Result<ChannelManager<ChanSigner, M, T, K, F>, secp256k1::Error> {
 646                 let secp_ctx = Secp256k1::new();
 647
 648                 let res = ChannelManager {
 649                         default_configuration: config.clone(),
 650                         genesis_hash: genesis_block(network).header.bitcoin_hash(),
 651                         fee_estimator: fee_est,
 652                         monitor,
 653                         tx_broadcaster,
 654
 655                         latest_block_height: AtomicUsize::new(current_blockchain_height),
 656                         last_block_hash: Mutex::new(Default::default()),
 657                         secp_ctx,
 658
 659                         channel_state: Mutex::new(ChannelHolder{
 660                                 by_id: HashMap::new(),
 661                                 short_to_id: HashMap::new(),
 662                                 forward_htlcs: HashMap::new(),
 663                                 claimable_htlcs: HashMap::new(),
 664                                 pending_msg_events: Vec::new(),
 665                         }),
 666                         our_network_key: keys_manager.get_node_secret(),
 667
 668                         per_peer_state: RwLock::new(HashMap::new()),
 669
 670                         pending_events: Mutex::new(Vec::new()),
 671                         total_consistency_lock: RwLock::new(()),
 672
 673                         keys_manager,
 674
 675                         logger,
 676                 };
 677
 678                 Ok(res)
 679         }
 680
 681         /// Creates a new outbound channel to the given remote node and with the given value.
 682         ///
 683         /// user_id will be provided back as user_channel_id in FundingGenerationReady and
 684         /// FundingBroadcastSafe events to allow tracking of which events correspond with which
 685         /// create_channel call. Note that user_channel_id defaults to 0 for inbound channels, so you
 686         /// may wish to avoid using 0 for user_id here.
 687         ///
 688         /// If successful, will generate a SendOpenChannel message event, so you should probably poll
 689         /// PeerManager::process_events afterwards.
 690         ///
 691         /// Raises APIError::APIMisuseError when channel_value_satoshis > 2**24 or push_msat is
 692         /// greater than channel_value_satoshis * 1k or channel_value_satoshis is < 1000.
 693         pub fn create_channel(&self, their_network_key: PublicKey, channel_value_satoshis: u64, push_msat: u64, user_id: u64, override_config: Option<UserConfig>) -> Result<(), APIError> {
 694                 if channel_value_satoshis < 1000 {
 695                         return Err(APIError::APIMisuseError { err: "channel_value must be at least 1000 satoshis" });
 696                 }
 697
 698                 let config = if override_config.is_some() { override_config.as_ref().unwrap() } else { &self.default_configuration };
 699                 let channel = Channel::new_outbound(&self.fee_estimator, &self.keys_manager, their_network_key, channel_value_satoshis, push_msat, user_id, Arc::clone(&self.logger), config)?;
 700                 let res = channel.get_open_channel(self.genesis_hash.clone(), &self.fee_estimator);
 701
 702                 let _ = self.total_consistency_lock.read().unwrap();
 703                 let mut channel_state = self.channel_state.lock().unwrap();
 704                 match channel_state.by_id.entry(channel.channel_id()) {
 705                         hash_map::Entry::Occupied(_) => {
 706                                 if cfg!(feature = "fuzztarget") {
 707                                         return Err(APIError::APIMisuseError { err: "Fuzzy bad RNG" });
 708                                 } else {
 709                                         panic!("RNG is bad???");
 710                                 }
 711                         },
 712                         hash_map::Entry::Vacant(entry) => { entry.insert(channel); }
 713                 }
 714                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendOpenChannel {
 715                         node_id: their_network_key,
 716                         msg: res,
 717                 });
 718                 Ok(())
 719         }
 720
 721         fn list_channels_with_filter<Fn: FnMut(&(&[u8; 32], &Channel<ChanSigner>)) -> bool>(&self, f: Fn) -> Vec<ChannelDetails> {
 722                 let mut res = Vec::new();
 723                 {
 724                         let channel_state = self.channel_state.lock().unwrap();
 725                         res.reserve(channel_state.by_id.len());
 726                         for (channel_id, channel) in channel_state.by_id.iter().filter(f) {
 727                                 let (inbound_capacity_msat, outbound_capacity_msat) = channel.get_inbound_outbound_available_balance_msat();
 728                                 res.push(ChannelDetails {
 729                                         channel_id: (*channel_id).clone(),
 730                                         short_channel_id: channel.get_short_channel_id(),
 731                                         remote_network_id: channel.get_their_node_id(),
 732                                         counterparty_features: InitFeatures::empty(),
 733                                         channel_value_satoshis: channel.get_value_satoshis(),
 734                                         inbound_capacity_msat,
 735                                         outbound_capacity_msat,
 736                                         user_id: channel.get_user_id(),
 737                                         is_live: channel.is_live(),
 738                                 });
 739                         }
 740                 }
 741                 let per_peer_state = self.per_peer_state.read().unwrap();
 742                 for chan in res.iter_mut() {
 743                         if let Some(peer_state) = per_peer_state.get(&chan.remote_network_id) {
 744                                 chan.counterparty_features = peer_state.lock().unwrap().latest_features.clone();
 745                         }
 746                 }
 747                 res
 748         }
 749
 750         /// Gets the list of open channels, in random order. See ChannelDetail field documentation for
 751         /// more information.
 752         pub fn list_channels(&self) -> Vec<ChannelDetails> {
 753                 self.list_channels_with_filter(|_| true)
 754         }
 755
 756         /// Gets the list of usable channels, in random order. Useful as an argument to
 757         /// Router::get_route to ensure non-announced channels are used.
 758         ///
 759         /// These are guaranteed to have their is_live value set to true, see the documentation for
 760         /// ChannelDetails::is_live for more info on exactly what the criteria are.
 761         pub fn list_usable_channels(&self) -> Vec<ChannelDetails> {
 762                 // Note we use is_live here instead of usable which leads to somewhat confused
 763                 // internal/external nomenclature, but that's ok cause that's probably what the user
 764                 // really wanted anyway.
 765                 self.list_channels_with_filter(|&(_, ref channel)| channel.is_live())
 766         }
 767
 768         /// Begins the process of closing a channel. After this call (plus some timeout), no new HTLCs
 769         /// will be accepted on the given channel, and after additional timeout/the closing of all
 770         /// pending HTLCs, the channel will be closed on chain.
 771         ///
 772         /// May generate a SendShutdown message event on success, which should be relayed.
 773         pub fn close_channel(&self, channel_id: &[u8; 32]) -> Result<(), APIError> {
 774                 let _ = self.total_consistency_lock.read().unwrap();
 775
 776                 let (mut failed_htlcs, chan_option) = {
 777                         let mut channel_state_lock = self.channel_state.lock().unwrap();
 778                         let channel_state = &mut *channel_state_lock;
 779                         match channel_state.by_id.entry(channel_id.clone()) {
 780                                 hash_map::Entry::Occupied(mut chan_entry) => {
 781                                         let (shutdown_msg, failed_htlcs) = chan_entry.get_mut().get_shutdown()?;
 782                                         channel_state.pending_msg_events.push(events::MessageSendEvent::SendShutdown {
 783                                                 node_id: chan_entry.get().get_their_node_id(),
 784                                                 msg: shutdown_msg
 785                                         });
 786                                         if chan_entry.get().is_shutdown() {
 787                                                 if let Some(short_id) = chan_entry.get().get_short_channel_id() {
 788                                                         channel_state.short_to_id.remove(&short_id);
 789                                                 }
 790                                                 (failed_htlcs, Some(chan_entry.remove_entry().1))
 791                                         } else { (failed_htlcs, None) }
 792                                 },
 793                                 hash_map::Entry::Vacant(_) => return Err(APIError::ChannelUnavailable{err: "No such channel"})
 794                         }
 795                 };
 796                 for htlc_source in failed_htlcs.drain(..) {
 797                         self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), htlc_source.0, &htlc_source.1, HTLCFailReason::Reason { failure_code: 0x4000 | 8, data: Vec::new() });
 798                 }
 799                 let chan_update = if let Some(chan) = chan_option {
 800                         if let Ok(update) = self.get_channel_update(&chan) {
 801                                 Some(update)
 802                         } else { None }
 803                 } else { None };
 804
 805                 if let Some(update) = chan_update {
 806                         let mut channel_state = self.channel_state.lock().unwrap();
 807                         channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
 808                                 msg: update
 809                         });
 810                 }
 811
 812                 Ok(())
 813         }
 814
 815         #[inline]
 816         fn finish_force_close_channel(&self, shutdown_res: ShutdownResult) {
 817                 let (local_txn, mut failed_htlcs) = shutdown_res;
 818                 log_trace!(self, "Finishing force-closure of channel with {} transactions to broadcast and {} HTLCs to fail", local_txn.len(), failed_htlcs.len());
 819                 for htlc_source in failed_htlcs.drain(..) {
 820                         self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), htlc_source.0, &htlc_source.1, HTLCFailReason::Reason { failure_code: 0x4000 | 8, data: Vec::new() });
 821                 }
 822                 for tx in local_txn {
 823                         log_trace!(self, "Broadcast onchain {}", log_tx!(tx));
 824                         self.tx_broadcaster.broadcast_transaction(&tx);
 825                 }
 826         }
 827
 828         /// Force closes a channel, immediately broadcasting the latest local commitment transaction to
 829         /// the chain and rejecting new HTLCs on the given channel.
 830         pub fn force_close_channel(&self, channel_id: &[u8; 32]) {
 831                 let _ = self.total_consistency_lock.read().unwrap();
 832
 833                 let mut chan = {
 834                         let mut channel_state_lock = self.channel_state.lock().unwrap();
 835                         let channel_state = &mut *channel_state_lock;
 836                         if let Some(chan) = channel_state.by_id.remove(channel_id) {
 837                                 if let Some(short_id) = chan.get_short_channel_id() {
 838                                         channel_state.short_to_id.remove(&short_id);
 839                                 }
 840                                 chan
 841                         } else {
 842                                 return;
 843                         }
 844                 };
 845                 log_trace!(self, "Force-closing channel {}", log_bytes!(channel_id[..]));
 846                 self.finish_force_close_channel(chan.force_shutdown());
 847                 if let Ok(update) = self.get_channel_update(&chan) {
 848                         let mut channel_state = self.channel_state.lock().unwrap();
 849                         channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
 850                                 msg: update
 851                         });
 852                 }
 853         }
 854
 855         /// Force close all channels, immediately broadcasting the latest local commitment transaction
 856         /// for each to the chain and rejecting new HTLCs on each.
 857         pub fn force_close_all_channels(&self) {
 858                 for chan in self.list_channels() {
 859                         self.force_close_channel(&chan.channel_id);
 860                 }
 861         }
 862
 863         fn decode_update_add_htlc_onion(&self, msg: &msgs::UpdateAddHTLC) -> (PendingHTLCStatus, MutexGuard<ChannelHolder<ChanSigner>>) {
 864                 macro_rules! return_malformed_err {
 865                         ($msg: expr, $err_code: expr) => {
 866                                 {
 867                                         log_info!(self, "Failed to accept/forward incoming HTLC: {}", $msg);
 868                                         return (PendingHTLCStatus::Fail(HTLCFailureMsg::Malformed(msgs::UpdateFailMalformedHTLC {
 869                                                 channel_id: msg.channel_id,
 870                                                 htlc_id: msg.htlc_id,
 871                                                 sha256_of_onion: Sha256::hash(&msg.onion_routing_packet.hop_data).into_inner(),
 872                                                 failure_code: $err_code,
 873                                         })), self.channel_state.lock().unwrap());
 874                                 }
 875                         }
 876                 }
 877
 878                 if let Err(_) = msg.onion_routing_packet.public_key {
 879                         return_malformed_err!("invalid ephemeral pubkey", 0x8000 | 0x4000 | 6);
 880                 }
 881
 882                 let shared_secret = {
 883                         let mut arr = [0; 32];
 884                         arr.copy_from_slice(&SharedSecret::new(&msg.onion_routing_packet.public_key.unwrap(), &self.our_network_key)[..]);
 885                         arr
 886                 };
 887                 let (rho, mu) = onion_utils::gen_rho_mu_from_shared_secret(&shared_secret);
 888
 889                 if msg.onion_routing_packet.version != 0 {
 890                         //TODO: Spec doesn't indicate if we should only hash hop_data here (and in other
 891                         //sha256_of_onion error data packets), or the entire onion_routing_packet. Either way,
 892                         //the hash doesn't really serve any purpose - in the case of hashing all data, the
 893                         //receiving node would have to brute force to figure out which version was put in the
 894                         //packet by the node that send us the message, in the case of hashing the hop_data, the
 895                         //node knows the HMAC matched, so they already know what is there...
 896                         return_malformed_err!("Unknown onion packet version", 0x8000 | 0x4000 | 4);
 897                 }
 898
 899                 let mut hmac = HmacEngine::<Sha256>::new(&mu);
 900                 hmac.input(&msg.onion_routing_packet.hop_data);
 901                 hmac.input(&msg.payment_hash.0[..]);
 902                 if !fixed_time_eq(&Hmac::from_engine(hmac).into_inner(), &msg.onion_routing_packet.hmac) {
 903                         return_malformed_err!("HMAC Check failed", 0x8000 | 0x4000 | 5);
 904                 }
 905
 906                 let mut channel_state = None;
 907                 macro_rules! return_err {
 908                         ($msg: expr, $err_code: expr, $data: expr) => {
 909                                 {
 910                                         log_info!(self, "Failed to accept/forward incoming HTLC: {}", $msg);
 911                                         if channel_state.is_none() {
 912                                                 channel_state = Some(self.channel_state.lock().unwrap());
 913                                         }
 914                                         return (PendingHTLCStatus::Fail(HTLCFailureMsg::Relay(msgs::UpdateFailHTLC {
 915                                                 channel_id: msg.channel_id,
 916                                                 htlc_id: msg.htlc_id,
 917                                                 reason: onion_utils::build_first_hop_failure_packet(&shared_secret, $err_code, $data),
 918                                         })), channel_state.unwrap());
 919                                 }
 920                         }
 921                 }
 922
 923                 let mut chacha = ChaCha20::new(&rho, &[0u8; 8]);
 924                 let mut chacha_stream = ChaChaReader { chacha: &mut chacha, read: Cursor::new(&msg.onion_routing_packet.hop_data[..]) };
 925                 let (next_hop_data, next_hop_hmac) = {
 926                         match msgs::OnionHopData::read(&mut chacha_stream) {
 927                                 Err(err) => {
 928                                         let error_code = match err {
 929                                                 msgs::DecodeError::UnknownVersion => 0x4000 | 1, // unknown realm byte
 930                                                 msgs::DecodeError::UnknownRequiredFeature|
 931                                                 msgs::DecodeError::InvalidValue|
 932                                                 msgs::DecodeError::ShortRead => 0x4000 | 22, // invalid_onion_payload
 933                                                 _ => 0x2000 | 2, // Should never happen
 934                                         };
 935                                         return_err!("Unable to decode our hop data", error_code, &[0;0]);
 936                                 },
 937                                 Ok(msg) => {
 938                                         let mut hmac = [0; 32];
 939                                         if let Err(_) = chacha_stream.read_exact(&mut hmac[..]) {
 940                                                 return_err!("Unable to decode hop data", 0x4000 | 22, &[0;0]);
 941                                         }
 942                                         (msg, hmac)
 943                                 },
 944                         }
 945                 };
 946
 947                 let pending_forward_info = if next_hop_hmac == [0; 32] {
 948                                 #[cfg(test)]
 949                                 {
 950                                         // In tests, make sure that the initial onion pcket data is, at least, non-0.
 951                                         // We could do some fancy randomness test here, but, ehh, whatever.
 952                                         // This checks for the issue where you can calculate the path length given the
 953                                         // onion data as all the path entries that the originator sent will be here
 954                                         // as-is (and were originally 0s).
 955                                         // Of course reverse path calculation is still pretty easy given naive routing
 956                                         // algorithms, but this fixes the most-obvious case.
 957                                         let mut next_bytes = [0; 32];
 958                                         chacha_stream.read_exact(&mut next_bytes).unwrap();
 959                                         assert_ne!(next_bytes[..], [0; 32][..]);
 960                                         chacha_stream.read_exact(&mut next_bytes).unwrap();
 961                                         assert_ne!(next_bytes[..], [0; 32][..]);
 962                                 }
 963
 964                                 // OUR PAYMENT!
 965                                 // final_expiry_too_soon
 966                                 if (msg.cltv_expiry as u64) < self.latest_block_height.load(Ordering::Acquire) as u64 + (CLTV_CLAIM_BUFFER + LATENCY_GRACE_PERIOD_BLOCKS) as u64 {
 967                                         return_err!("The final CLTV expiry is too soon to handle", 17, &[0;0]);
 968                                 }
 969                                 // final_incorrect_htlc_amount
 970                                 if next_hop_data.amt_to_forward > msg.amount_msat {
 971                                         return_err!("Upstream node sent less than we were supposed to receive in payment", 19, &byte_utils::be64_to_array(msg.amount_msat));
 972                                 }
 973                                 // final_incorrect_cltv_expiry
 974                                 if next_hop_data.outgoing_cltv_value != msg.cltv_expiry {
 975                                         return_err!("Upstream node set CLTV to the wrong value", 18, &byte_utils::be32_to_array(msg.cltv_expiry));
 976                                 }
 977
 978                                 // Note that we could obviously respond immediately with an update_fulfill_htlc
 979                                 // message, however that would leak that we are the recipient of this payment, so
 980                                 // instead we stay symmetric with the forwarding case, only responding (after a
 981                                 // delay) once they've send us a commitment_signed!
 982
 983                                 PendingHTLCStatus::Forward(PendingHTLCInfo {
 984                                         onion_packet: None,
 985                                         payment_hash: msg.payment_hash.clone(),
 986                                         short_channel_id: 0,
 987                                         incoming_shared_secret: shared_secret,
 988                                         amt_to_forward: next_hop_data.amt_to_forward,
 989                                         outgoing_cltv_value: next_hop_data.outgoing_cltv_value,
 990                                 })
 991                         } else {
 992                                 let mut new_packet_data = [0; 20*65];
 993                                 let read_pos = chacha_stream.read(&mut new_packet_data).unwrap();
 994                                 #[cfg(debug_assertions)]
 995                                 {
 996                                         // Check two things:
 997                                         // a) that the behavior of our stream here will return Ok(0) even if the TLV
 998                                         //    read above emptied out our buffer and the unwrap() wont needlessly panic
 999                                         // b) that we didn't somehow magically end up with extra data.
1000                                         let mut t = [0; 1];
1001                                         debug_assert!(chacha_stream.read(&mut t).unwrap() == 0);
1002                                 }
1003                                 // Once we've emptied the set of bytes our peer gave us, encrypt 0 bytes until we
1004                                 // fill the onion hop data we'll forward to our next-hop peer.
1005                                 chacha_stream.chacha.process_in_place(&mut new_packet_data[read_pos..]);
1006
1007                                 let mut new_pubkey = msg.onion_routing_packet.public_key.unwrap();
1008
1009                                 let blinding_factor = {
1010                                         let mut sha = Sha256::engine();
1011                                         sha.input(&new_pubkey.serialize()[..]);
1012                                         sha.input(&shared_secret);
1013                                         Sha256::from_engine(sha).into_inner()
1014                                 };
1015
1016                                 let public_key = if let Err(e) = new_pubkey.mul_assign(&self.secp_ctx, &blinding_factor[..]) {
1017                                         Err(e)
1018                                 } else { Ok(new_pubkey) };
1019
1020                                 let outgoing_packet = msgs::OnionPacket {
1021                                         version: 0,
1022                                         public_key,
1023                                         hop_data: new_packet_data,
1024                                         hmac: next_hop_hmac.clone(),
1025                                 };
1026
1027                                 let short_channel_id = match next_hop_data.format {
1028                                         msgs::OnionHopDataFormat::Legacy { short_channel_id } => short_channel_id,
1029                                         msgs::OnionHopDataFormat::NonFinalNode { short_channel_id } => short_channel_id,
1030                                         msgs::OnionHopDataFormat::FinalNode => {
1031                                                 return_err!("Final Node OnionHopData provided for us as an intermediary node", 0x4000 | 22, &[0;0]);
1032                                         },
1033                                 };
1034
1035                                 PendingHTLCStatus::Forward(PendingHTLCInfo {
1036                                         onion_packet: Some(outgoing_packet),
1037                                         payment_hash: msg.payment_hash.clone(),
1038                                         short_channel_id: short_channel_id,
1039                                         incoming_shared_secret: shared_secret,
1040                                         amt_to_forward: next_hop_data.amt_to_forward,
1041                                         outgoing_cltv_value: next_hop_data.outgoing_cltv_value,
1042                                 })
1043                         };
1044
1045                 channel_state = Some(self.channel_state.lock().unwrap());
1046                 if let &PendingHTLCStatus::Forward(PendingHTLCInfo { ref onion_packet, ref short_channel_id, ref amt_to_forward, ref outgoing_cltv_value, .. }) = &pending_forward_info {
1047                         if onion_packet.is_some() { // If short_channel_id is 0 here, we'll reject them in the body here
1048                                 let id_option = channel_state.as_ref().unwrap().short_to_id.get(&short_channel_id).cloned();
1049                                 let forwarding_id = match id_option {
1050                                         None => { // unknown_next_peer
1051                                                 return_err!("Don't have available channel for forwarding as requested.", 0x4000 | 10, &[0;0]);
1052                                         },
1053                                         Some(id) => id.clone(),
1054                                 };
1055                                 if let Some((err, code, chan_update)) = loop {
1056                                         let chan = channel_state.as_mut().unwrap().by_id.get_mut(&forwarding_id).unwrap();
1057
1058                                         // Note that we could technically not return an error yet here and just hope
1059                                         // that the connection is reestablished or monitor updated by the time we get
1060                                         // around to doing the actual forward, but better to fail early if we can and
1061                                         // hopefully an attacker trying to path-trace payments cannot make this occur
1062                                         // on a small/per-node/per-channel scale.
1063                                         if !chan.is_live() { // channel_disabled
1064                                                 break Some(("Forwarding channel is not in a ready state.", 0x1000 | 20, Some(self.get_channel_update(chan).unwrap())));
1065                                         }
1066                                         if *amt_to_forward < chan.get_their_htlc_minimum_msat() { // amount_below_minimum
1067                                                 break Some(("HTLC amount was below the htlc_minimum_msat", 0x1000 | 11, Some(self.get_channel_update(chan).unwrap())));
1068                                         }
1069                                         let fee = amt_to_forward.checked_mul(chan.get_fee_proportional_millionths() as u64).and_then(|prop_fee| { (prop_fee / 1000000).checked_add(chan.get_our_fee_base_msat(&self.fee_estimator) as u64) });
1070                                         if fee.is_none() || msg.amount_msat < fee.unwrap() || (msg.amount_msat - fee.unwrap()) < *amt_to_forward { // fee_insufficient
1071                                                 break Some(("Prior hop has deviated from specified fees parameters or origin node has obsolete ones", 0x1000 | 12, Some(self.get_channel_update(chan).unwrap())));
1072                                         }
1073                                         if (msg.cltv_expiry as u64) < (*outgoing_cltv_value) as u64 + CLTV_EXPIRY_DELTA as u64 { // incorrect_cltv_expiry
1074                                                 break Some(("Forwarding node has tampered with the intended HTLC values or origin node has an obsolete cltv_expiry_delta", 0x1000 | 13, Some(self.get_channel_update(chan).unwrap())));
1075                                         }
1076                                         let cur_height = self.latest_block_height.load(Ordering::Acquire) as u32 + 1;
1077                                         // We want to have at least LATENCY_GRACE_PERIOD_BLOCKS to fail prior to going on chain CLAIM_BUFFER blocks before expiration
1078                                         if msg.cltv_expiry <= cur_height + CLTV_CLAIM_BUFFER + LATENCY_GRACE_PERIOD_BLOCKS as u32 { // expiry_too_soon
1079                                                 break Some(("CLTV expiry is too close", 0x1000 | 14, Some(self.get_channel_update(chan).unwrap())));
1080                                         }
1081                                         if msg.cltv_expiry > cur_height + CLTV_FAR_FAR_AWAY as u32 { // expiry_too_far
1082                                                 break Some(("CLTV expiry is too far in the future", 21, None));
1083                                         }
1084                                         break None;
1085                                 }
1086                                 {
1087                                         let mut res = Vec::with_capacity(8 + 128);
1088                                         if let Some(chan_update) = chan_update {
1089                                                 if code == 0x1000 | 11 || code == 0x1000 | 12 {
1090                                                         res.extend_from_slice(&byte_utils::be64_to_array(msg.amount_msat));
1091                                                 }
1092                                                 else if code == 0x1000 | 13 {
1093                                                         res.extend_from_slice(&byte_utils::be32_to_array(msg.cltv_expiry));
1094                                                 }
1095                                                 else if code == 0x1000 | 20 {
1096                                                         res.extend_from_slice(&byte_utils::be16_to_array(chan_update.contents.flags));
1097                                                 }
1098                                                 res.extend_from_slice(&chan_update.encode_with_len()[..]);
1099                                         }
1100                                         return_err!(err, code, &res[..]);
1101                                 }
1102                         }
1103                 }
1104
1105                 (pending_forward_info, channel_state.unwrap())
1106         }
1107
1108         /// only fails if the channel does not yet have an assigned short_id
1109         /// May be called with channel_state already locked!
1110         fn get_channel_update(&self, chan: &Channel<ChanSigner>) -> Result<msgs::ChannelUpdate, LightningError> {
1111                 let short_channel_id = match chan.get_short_channel_id() {
1112                         None => return Err(LightningError{err: "Channel not yet established", action: msgs::ErrorAction::IgnoreError}),
1113                         Some(id) => id,
1114                 };
1115
1116                 let were_node_one = PublicKey::from_secret_key(&self.secp_ctx, &self.our_network_key).serialize()[..] < chan.get_their_node_id().serialize()[..];
1117
1118                 let unsigned = msgs::UnsignedChannelUpdate {
1119                         chain_hash: self.genesis_hash,
1120                         short_channel_id: short_channel_id,
1121                         timestamp: chan.get_channel_update_count(),
1122                         flags: (!were_node_one) as u16 | ((!chan.is_live() as u16) << 1),
1123                         cltv_expiry_delta: CLTV_EXPIRY_DELTA,
1124                         htlc_minimum_msat: chan.get_our_htlc_minimum_msat(),
1125                         fee_base_msat: chan.get_our_fee_base_msat(&self.fee_estimator),
1126                         fee_proportional_millionths: chan.get_fee_proportional_millionths(),
1127                         excess_data: Vec::new(),
1128                 };
1129
1130                 let msg_hash = Sha256dHash::hash(&unsigned.encode()[..]);
1131                 let sig = self.secp_ctx.sign(&hash_to_message!(&msg_hash[..]), &self.our_network_key);
1132
1133                 Ok(msgs::ChannelUpdate {
1134                         signature: sig,
1135                         contents: unsigned
1136                 })
1137         }
1138
1139         /// Sends a payment along a given route.
1140         ///
1141         /// Value parameters are provided via the last hop in route, see documentation for RouteHop
1142         /// fields for more info.
1143         ///
1144         /// Note that if the payment_hash already exists elsewhere (eg you're sending a duplicative
1145         /// payment), we don't do anything to stop you! We always try to ensure that if the provided
1146         /// next hop knows the preimage to payment_hash they can claim an additional amount as
1147         /// specified in the last hop in the route! Thus, you should probably do your own
1148         /// payment_preimage tracking (which you should already be doing as they represent "proof of
1149         /// payment") and prevent double-sends yourself.
1150         ///
1151         /// May generate a SendHTLCs message event on success, which should be relayed.
1152         ///
1153         /// Raises APIError::RoutError when invalid route or forward parameter
1154         /// (cltv_delta, fee, node public key) is specified.
1155         /// Raises APIError::ChannelUnavailable if the next-hop channel is not available for updates
1156         /// (including due to previous monitor update failure or new permanent monitor update failure).
1157         /// Raised APIError::MonitorUpdateFailed if a new monitor update failure prevented sending the
1158         /// relevant updates.
1159         ///
1160         /// In case of APIError::RouteError/APIError::ChannelUnavailable, the payment send has failed
1161         /// and you may wish to retry via a different route immediately.
1162         /// In case of APIError::MonitorUpdateFailed, the commitment update has been irrevocably
1163         /// committed on our end and we're just waiting for a monitor update to send it. Do NOT retry
1164         /// the payment via a different route unless you intend to pay twice!
1165         pub fn send_payment(&self, route: Route, payment_hash: PaymentHash) -> Result<(), APIError> {
1166                 if route.hops.len() < 1 || route.hops.len() > 20 {
1167                         return Err(APIError::RouteError{err: "Route didn't go anywhere/had bogus size"});
1168                 }
1169                 let our_node_id = self.get_our_node_id();
1170                 for (idx, hop) in route.hops.iter().enumerate() {
1171                         if idx != route.hops.len() - 1 && hop.pubkey == our_node_id {
1172                                 return Err(APIError::RouteError{err: "Route went through us but wasn't a simple rebalance loop to us"});
1173                         }
1174                 }
1175
1176                 let (session_priv, prng_seed) = self.keys_manager.get_onion_rand();
1177
1178                 let cur_height = self.latest_block_height.load(Ordering::Acquire) as u32 + 1;
1179
1180                 let onion_keys = secp_call!(onion_utils::construct_onion_keys(&self.secp_ctx, &route, &session_priv),
1181                                 APIError::RouteError{err: "Pubkey along hop was maliciously selected"});
1182                 let (onion_payloads, htlc_msat, htlc_cltv) = onion_utils::build_onion_payloads(&route, cur_height)?;
1183                 if onion_utils::route_size_insane(&onion_payloads) {
1184                         return Err(APIError::RouteError{err: "Route size too large considering onion data"});
1185                 }
1186                 let onion_packet = onion_utils::construct_onion_packet(onion_payloads, onion_keys, prng_seed, &payment_hash);
1187
1188                 let _ = self.total_consistency_lock.read().unwrap();
1189
1190                 let mut channel_lock = self.channel_state.lock().unwrap();
1191                 let err: Result<(), _> = loop {
1192
1193                         let id = match channel_lock.short_to_id.get(&route.hops.first().unwrap().short_channel_id) {
1194                                 None => return Err(APIError::ChannelUnavailable{err: "No channel available with first hop!"}),
1195                                 Some(id) => id.clone(),
1196                         };
1197
1198                         let channel_state = &mut *channel_lock;
1199                         if let hash_map::Entry::Occupied(mut chan) = channel_state.by_id.entry(id) {
1200                                 match {
1201                                         if chan.get().get_their_node_id() != route.hops.first().unwrap().pubkey {
1202                                                 return Err(APIError::RouteError{err: "Node ID mismatch on first hop!"});
1203                                         }
1204                                         if !chan.get().is_live() {
1205                                                 return Err(APIError::ChannelUnavailable{err: "Peer for first hop currently disconnected/pending monitor update!"});
1206                                         }
1207                                         break_chan_entry!(self, chan.get_mut().send_htlc_and_commit(htlc_msat, payment_hash.clone(), htlc_cltv, HTLCSource::OutboundRoute {
1208                                                 route: route.clone(),
1209                                                 session_priv: session_priv.clone(),
1210                                                 first_hop_htlc_msat: htlc_msat,
1211                                         }, onion_packet), channel_state, chan)
1212                                 } {
1213                                         Some((update_add, commitment_signed, monitor_update)) => {
1214                                                 if let Err(e) = self.monitor.update_monitor(chan.get().get_funding_txo().unwrap(), monitor_update) {
1215                                                         maybe_break_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::CommitmentFirst, false, true);
1216                                                         // Note that MonitorUpdateFailed here indicates (per function docs)
1217                                                         // that we will resent the commitment update once we unfree monitor
1218                                                         // updating, so we have to take special care that we don't return
1219                                                         // something else in case we will resend later!
1220                                                         return Err(APIError::MonitorUpdateFailed);
1221                                                 }
1222
1223                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
1224                                                         node_id: route.hops.first().unwrap().pubkey,
1225                                                         updates: msgs::CommitmentUpdate {
1226                                                                 update_add_htlcs: vec![update_add],
1227                                                                 update_fulfill_htlcs: Vec::new(),
1228                                                                 update_fail_htlcs: Vec::new(),
1229                                                                 update_fail_malformed_htlcs: Vec::new(),
1230                                                                 update_fee: None,
1231                                                                 commitment_signed,
1232                                                         },
1233                                                 });
1234                                         },
1235                                         None => {},
1236                                 }
1237                         } else { unreachable!(); }
1238                         return Ok(());
1239                 };
1240
1241                 match handle_error!(self, err, route.hops.first().unwrap().pubkey, channel_lock) {
1242                         Ok(_) => unreachable!(),
1243                         Err(e) => { Err(APIError::ChannelUnavailable { err: e.err }) }
1244                 }
1245         }
1246
1247         /// Call this upon creation of a funding transaction for the given channel.
1248         ///
1249         /// Note that ALL inputs in the transaction pointed to by funding_txo MUST spend SegWit outputs
1250         /// or your counterparty can steal your funds!
1251         ///
1252         /// Panics if a funding transaction has already been provided for this channel.
1253         ///
1254         /// May panic if the funding_txo is duplicative with some other channel (note that this should
1255         /// be trivially prevented by using unique funding transaction keys per-channel).
1256         pub fn funding_transaction_generated(&self, temporary_channel_id: &[u8; 32], funding_txo: OutPoint) {
1257                 let _ = self.total_consistency_lock.read().unwrap();
1258
1259                 let (mut chan, msg, chan_monitor) = {
1260                         let mut channel_state = self.channel_state.lock().unwrap();
1261                         let (res, chan) = match channel_state.by_id.remove(temporary_channel_id) {
1262                                 Some(mut chan) => {
1263                                         (chan.get_outbound_funding_created(funding_txo)
1264                                                 .map_err(|e| if let ChannelError::Close(msg) = e {
1265                                                         MsgHandleErrInternal::from_finish_shutdown(msg, chan.channel_id(), chan.force_shutdown(), None)
1266                                                 } else { unreachable!(); })
1267                                         , chan)
1268                                 },
1269                                 None => return
1270                         };
1271                         match handle_error!(self, res, chan.get_their_node_id(), channel_state) {
1272                                 Ok(funding_msg) => {
1273                                         (chan, funding_msg.0, funding_msg.1)
1274                                 },
1275                                 Err(_) => { return; }
1276                         }
1277                 };
1278                 // Because we have exclusive ownership of the channel here we can release the channel_state
1279                 // lock before add_monitor
1280                 if let Err(e) = self.monitor.add_monitor(chan_monitor.get_funding_txo().unwrap(), chan_monitor) {
1281                         match e {
1282                                 ChannelMonitorUpdateErr::PermanentFailure => {
1283                                         {
1284                                                 let mut channel_state = self.channel_state.lock().unwrap();
1285                                                 match handle_error!(self, Err(MsgHandleErrInternal::from_finish_shutdown("ChannelMonitor storage failure", *temporary_channel_id, chan.force_shutdown(), None)), chan.get_their_node_id(), channel_state) {
1286                                                         Err(_) => { return; },
1287                                                         Ok(()) => unreachable!(),
1288                                                 }
1289                                         }
1290                                 },
1291                                 ChannelMonitorUpdateErr::TemporaryFailure => {
1292                                         // Its completely fine to continue with a FundingCreated until the monitor
1293                                         // update is persisted, as long as we don't generate the FundingBroadcastSafe
1294                                         // until the monitor has been safely persisted (as funding broadcast is not,
1295                                         // in fact, safe).
1296                                         chan.monitor_update_failed(false, false, Vec::new(), Vec::new());
1297                                 },
1298                         }
1299                 }
1300
1301                 let mut channel_state = self.channel_state.lock().unwrap();
1302                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendFundingCreated {
1303                         node_id: chan.get_their_node_id(),
1304                         msg: msg,
1305                 });
1306                 match channel_state.by_id.entry(chan.channel_id()) {
1307                         hash_map::Entry::Occupied(_) => {
1308                                 panic!("Generated duplicate funding txid?");
1309                         },
1310                         hash_map::Entry::Vacant(e) => {
1311                                 e.insert(chan);
1312                         }
1313                 }
1314         }
1315
1316         fn get_announcement_sigs(&self, chan: &Channel<ChanSigner>) -> Option<msgs::AnnouncementSignatures> {
1317                 if !chan.should_announce() {
1318                         log_trace!(self, "Can't send announcement_signatures for private channel {}", log_bytes!(chan.channel_id()));
1319                         return None
1320                 }
1321
1322                 let (announcement, our_bitcoin_sig) = match chan.get_channel_announcement(self.get_our_node_id(), self.genesis_hash.clone()) {
1323                         Ok(res) => res,
1324                         Err(_) => return None, // Only in case of state precondition violations eg channel is closing
1325                 };
1326                 let msghash = hash_to_message!(&Sha256dHash::hash(&announcement.encode()[..])[..]);
1327                 let our_node_sig = self.secp_ctx.sign(&msghash, &self.our_network_key);
1328
1329                 Some(msgs::AnnouncementSignatures {
1330                         channel_id: chan.channel_id(),
1331                         short_channel_id: chan.get_short_channel_id().unwrap(),
1332                         node_signature: our_node_sig,
1333                         bitcoin_signature: our_bitcoin_sig,
1334                 })
1335         }
1336
1337         /// Processes HTLCs which are pending waiting on random forward delay.
1338         ///
1339         /// Should only really ever be called in response to a PendingHTLCsForwardable event.
1340         /// Will likely generate further events.
1341         pub fn process_pending_htlc_forwards(&self) {
1342                 let _ = self.total_consistency_lock.read().unwrap();
1343
1344                 let mut new_events = Vec::new();
1345                 let mut failed_forwards = Vec::new();
1346                 let mut handle_errors = Vec::new();
1347                 {
1348                         let mut channel_state_lock = self.channel_state.lock().unwrap();
1349                         let channel_state = &mut *channel_state_lock;
1350
1351                         for (short_chan_id, mut pending_forwards) in channel_state.forward_htlcs.drain() {
1352                                 if short_chan_id != 0 {
1353                                         let forward_chan_id = match channel_state.short_to_id.get(&short_chan_id) {
1354                                                 Some(chan_id) => chan_id.clone(),
1355                                                 None => {
1356                                                         failed_forwards.reserve(pending_forwards.len());
1357                                                         for forward_info in pending_forwards.drain(..) {
1358                                                                 match forward_info {
1359                                                                         HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info } => {
1360                                                                                 let htlc_source = HTLCSource::PreviousHopData(HTLCPreviousHopData {
1361                                                                                         short_channel_id: prev_short_channel_id,
1362                                                                                         htlc_id: prev_htlc_id,
1363                                                                                         incoming_packet_shared_secret: forward_info.incoming_shared_secret,
1364                                                                                 });
1365                                                                                 failed_forwards.push((htlc_source, forward_info.payment_hash, 0x4000 | 10, None));
1366                                                                         },
1367                                                                         HTLCForwardInfo::FailHTLC { .. } => {
1368                                                                                 // Channel went away before we could fail it. This implies
1369                                                                                 // the channel is now on chain and our counterparty is
1370                                                                                 // trying to broadcast the HTLC-Timeout, but that's their
1371                                                                                 // problem, not ours.
1372                                                                         }
1373                                                                 }
1374                                                         }
1375                                                         continue;
1376                                                 }
1377                                         };
1378                                         if let hash_map::Entry::Occupied(mut chan) = channel_state.by_id.entry(forward_chan_id) {
1379                                                 let mut add_htlc_msgs = Vec::new();
1380                                                 let mut fail_htlc_msgs = Vec::new();
1381                                                 for forward_info in pending_forwards.drain(..) {
1382                                                         match forward_info {
1383                                                                 HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info } => {
1384                                                                         log_trace!(self, "Adding HTLC from short id {} with payment_hash {} to channel with short id {} after delay", log_bytes!(forward_info.payment_hash.0), prev_short_channel_id, short_chan_id);
1385                                                                         let htlc_source = HTLCSource::PreviousHopData(HTLCPreviousHopData {
1386                                                                                 short_channel_id: prev_short_channel_id,
1387                                                                                 htlc_id: prev_htlc_id,
1388                                                                                 incoming_packet_shared_secret: forward_info.incoming_shared_secret,
1389                                                                         });
1390                                                                         match chan.get_mut().send_htlc(forward_info.amt_to_forward, forward_info.payment_hash, forward_info.outgoing_cltv_value, htlc_source.clone(), forward_info.onion_packet.unwrap()) {
1391                                                                                 Err(e) => {
1392                                                                                         if let ChannelError::Ignore(msg) = e {
1393                                                                                                 log_trace!(self, "Failed to forward HTLC with payment_hash {}: {}", log_bytes!(forward_info.payment_hash.0), msg);
1394                                                                                         } else {
1395                                                                                                 panic!("Stated return value requirements in send_htlc() were not met");
1396                                                                                         }
1397                                                                                         let chan_update = self.get_channel_update(chan.get()).unwrap();
1398                                                                                         failed_forwards.push((htlc_source, forward_info.payment_hash, 0x1000 | 7, Some(chan_update)));
1399                                                                                         continue;
1400                                                                                 },
1401                                                                                 Ok(update_add) => {
1402                                                                                         match update_add {
1403                                                                                                 Some(msg) => { add_htlc_msgs.push(msg); },
1404                                                                                                 None => {
1405                                                                                                         // Nothing to do here...we're waiting on a remote
1406                                                                                                         // revoke_and_ack before we can add anymore HTLCs. The Channel
1407                                                                                                         // will automatically handle building the update_add_htlc and
1408                                                                                                         // commitment_signed messages when we can.
1409                                                                                                         // TODO: Do some kind of timer to set the channel as !is_live()
1410                                                                                                         // as we don't really want others relying on us relaying through
1411                                                                                                         // this channel currently :/.
1412                                                                                                 }
1413                                                                                         }
1414                                                                                 }
1415                                                                         }
1416                                                                 },
1417                                                                 HTLCForwardInfo::FailHTLC { htlc_id, err_packet } => {
1418                                                                         log_trace!(self, "Failing HTLC back to channel with short id {} after delay", short_chan_id);
1419                                                                         match chan.get_mut().get_update_fail_htlc(htlc_id, err_packet) {
1420                                                                                 Err(e) => {
1421                                                                                         if let ChannelError::Ignore(msg) = e {
1422                                                                                                 log_trace!(self, "Failed to fail backwards to short_id {}: {}", short_chan_id, msg);
1423                                                                                         } else {
1424                                                                                                 panic!("Stated return value requirements in get_update_fail_htlc() were not met");
1425                                                                                         }
1426                                                                                         // fail-backs are best-effort, we probably already have one
1427                                                                                         // pending, and if not that's OK, if not, the channel is on
1428                                                                                         // the chain and sending the HTLC-Timeout is their problem.
1429                                                                                         continue;
1430                                                                                 },
1431                                                                                 Ok(Some(msg)) => { fail_htlc_msgs.push(msg); },
1432                                                                                 Ok(None) => {
1433                                                                                         // Nothing to do here...we're waiting on a remote
1434                                                                                         // revoke_and_ack before we can update the commitment
1435                                                                                         // transaction. The Channel will automatically handle
1436                                                                                         // building the update_fail_htlc and commitment_signed
1437                                                                                         // messages when we can.
1438                                                                                         // We don't need any kind of timer here as they should fail
1439                                                                                         // the channel onto the chain if they can't get our
1440                                                                                         // update_fail_htlc in time, it's not our problem.
1441                                                                                 }
1442                                                                         }
1443                                                                 },
1444                                                         }
1445                                                 }
1446
1447                                                 if !add_htlc_msgs.is_empty() || !fail_htlc_msgs.is_empty() {
1448                                                         let (commitment_msg, monitor_update) = match chan.get_mut().send_commitment() {
1449                                                                 Ok(res) => res,
1450                                                                 Err(e) => {
1451                                                                         // We surely failed send_commitment due to bad keys, in that case
1452                                                                         // close channel and then send error message to peer.
1453                                                                         let their_node_id = chan.get().get_their_node_id();
1454                                                                         let err: Result<(), _>  = match e {
1455                                                                                 ChannelError::Ignore(_) => {
1456                                                                                         panic!("Stated return value requirements in send_commitment() were not met");
1457                                                                                 },
1458                                                                                 ChannelError::Close(msg) => {
1459                                                                                         log_trace!(self, "Closing channel {} due to Close-required error: {}", log_bytes!(chan.key()[..]), msg);
1460                                                                                         let (channel_id, mut channel) = chan.remove_entry();
1461                                                                                         if let Some(short_id) = channel.get_short_channel_id() {
1462                                                                                                 channel_state.short_to_id.remove(&short_id);
1463                                                                                         }
1464                                                                                         Err(MsgHandleErrInternal::from_finish_shutdown(msg, channel_id, channel.force_shutdown(), self.get_channel_update(&channel).ok()))
1465                                                                                 },
1466                                                                                 ChannelError::CloseDelayBroadcast { .. } => { panic!("Wait is only generated on receipt of channel_reestablish, which is handled by try_chan_entry, we don't bother to support it here"); }
1467                                                                         };
1468                                                                         match handle_error!(self, err, their_node_id, channel_state) {
1469                                                                                 Ok(_) => unreachable!(),
1470                                                                                 Err(_) => { continue; },
1471                                                                         }
1472                                                                 }
1473                                                         };
1474                                                         if let Err(e) = self.monitor.update_monitor(chan.get().get_funding_txo().unwrap(), monitor_update) {
1475                                                                 handle_errors.push((chan.get().get_their_node_id(), handle_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::CommitmentFirst, false, true)));
1476                                                                 continue;
1477                                                         }
1478                                                         channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
1479                                                                 node_id: chan.get().get_their_node_id(),
1480                                                                 updates: msgs::CommitmentUpdate {
1481                                                                         update_add_htlcs: add_htlc_msgs,
1482                                                                         update_fulfill_htlcs: Vec::new(),
1483                                                                         update_fail_htlcs: fail_htlc_msgs,
1484                                                                         update_fail_malformed_htlcs: Vec::new(),
1485                                                                         update_fee: None,
1486                                                                         commitment_signed: commitment_msg,
1487                                                                 },
1488                                                         });
1489                                                 }
1490                                         } else {
1491                                                 unreachable!();
1492                                         }
1493                                 } else {
1494                                         for forward_info in pending_forwards.drain(..) {
1495                                                 match forward_info {
1496                                                         HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info } => {
1497                                                                 let prev_hop_data = HTLCPreviousHopData {
1498                                                                         short_channel_id: prev_short_channel_id,
1499                                                                         htlc_id: prev_htlc_id,
1500                                                                         incoming_packet_shared_secret: forward_info.incoming_shared_secret,
1501                                                                 };
1502                                                                 match channel_state.claimable_htlcs.entry(forward_info.payment_hash) {
1503                                                                         hash_map::Entry::Occupied(mut entry) => entry.get_mut().push((forward_info.amt_to_forward, prev_hop_data)),
1504                                                                         hash_map::Entry::Vacant(entry) => { entry.insert(vec![(forward_info.amt_to_forward, prev_hop_data)]); },
1505                                                                 };
1506                                                                 new_events.push(events::Event::PaymentReceived {
1507                                                                         payment_hash: forward_info.payment_hash,
1508                                                                         amt: forward_info.amt_to_forward,
1509                                                                 });
1510                                                         },
1511                                                         HTLCForwardInfo::FailHTLC { .. } => {
1512                                                                 panic!("Got pending fail of our own HTLC");
1513                                                         }
1514                                                 }
1515                                         }
1516                                 }
1517                         }
1518                 }
1519
1520                 for (htlc_source, payment_hash, failure_code, update) in failed_forwards.drain(..) {
1521                         match update {
1522                                 None => self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), htlc_source, &payment_hash, HTLCFailReason::Reason { failure_code, data: Vec::new() }),
1523                                 Some(chan_update) => self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), htlc_source, &payment_hash, HTLCFailReason::Reason { failure_code, data: chan_update.encode_with_len() }),
1524                         };
1525                 }
1526
1527                 if handle_errors.len() > 0 {
1528                         let mut channel_state_lock = self.channel_state.lock().unwrap();
1529                         for (their_node_id, err) in handle_errors.drain(..) {
1530                                 let _ = handle_error!(self, err, their_node_id, channel_state_lock);
1531                         }
1532                 }
1533
1534                 if new_events.is_empty() { return }
1535                 let mut events = self.pending_events.lock().unwrap();
1536                 events.append(&mut new_events);
1537         }
1538
1539         /// If a peer is disconnected we mark any channels with that peer as 'disabled'.
1540         /// After some time, if channels are still disabled we need to broadcast a ChannelUpdate
1541         /// to inform the network about the uselessness of these channels.
1542         ///
1543         /// This method handles all the details, and must be called roughly once per minute.
1544         pub fn timer_chan_freshness_every_min(&self) {
1545                 let _ = self.total_consistency_lock.read().unwrap();
1546                 let mut channel_state_lock = self.channel_state.lock().unwrap();
1547                 let channel_state = &mut *channel_state_lock;
1548                 for (_, chan) in channel_state.by_id.iter_mut() {
1549                         if chan.is_disabled_staged() && !chan.is_live() {
1550                                 if let Ok(update) = self.get_channel_update(&chan) {
1551                                         channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
1552                                                 msg: update
1553                                         });
1554                                 }
1555                                 chan.to_fresh();
1556                         } else if chan.is_disabled_staged() && chan.is_live() {
1557                                 chan.to_fresh();
1558                         } else if chan.is_disabled_marked() {
1559                                 chan.to_disabled_staged();
1560                         }
1561                 }
1562         }
1563
1564         /// Indicates that the preimage for payment_hash is unknown or the received amount is incorrect
1565         /// after a PaymentReceived event, failing the HTLC back to its origin and freeing resources
1566         /// along the path (including in our own channel on which we received it).
1567         /// Returns false if no payment was found to fail backwards, true if the process of failing the
1568         /// HTLC backwards has been started.
1569         pub fn fail_htlc_backwards(&self, payment_hash: &PaymentHash) -> bool {
1570                 let _ = self.total_consistency_lock.read().unwrap();
1571
1572                 let mut channel_state = Some(self.channel_state.lock().unwrap());
1573                 let removed_source = channel_state.as_mut().unwrap().claimable_htlcs.remove(payment_hash);
1574                 if let Some(mut sources) = removed_source {
1575                         for (recvd_value, htlc_with_hash) in sources.drain(..) {
1576                                 if channel_state.is_none() { channel_state = Some(self.channel_state.lock().unwrap()); }
1577                                 self.fail_htlc_backwards_internal(channel_state.take().unwrap(),
1578                                                 HTLCSource::PreviousHopData(htlc_with_hash), payment_hash,
1579                                                 HTLCFailReason::Reason { failure_code: 0x4000 | 15, data: byte_utils::be64_to_array(recvd_value).to_vec() });
1580                         }
1581                         true
1582                 } else { false }
1583         }
1584
1585         /// Fails an HTLC backwards to the sender of it to us.
1586         /// Note that while we take a channel_state lock as input, we do *not* assume consistency here.
1587         /// There are several callsites that do stupid things like loop over a list of payment_hashes
1588         /// to fail and take the channel_state lock for each iteration (as we take ownership and may
1589         /// drop it). In other words, no assumptions are made that entries in claimable_htlcs point to
1590         /// still-available channels.
1591         fn fail_htlc_backwards_internal(&self, mut channel_state_lock: MutexGuard<ChannelHolder<ChanSigner>>, source: HTLCSource, payment_hash: &PaymentHash, onion_error: HTLCFailReason) {
1592                 //TODO: There is a timing attack here where if a node fails an HTLC back to us they can
1593                 //identify whether we sent it or not based on the (I presume) very different runtime
1594                 //between the branches here. We should make this async and move it into the forward HTLCs
1595                 //timer handling.
1596                 match source {
1597                         HTLCSource::OutboundRoute { ref route, .. } => {
1598                                 log_trace!(self, "Failing outbound payment HTLC with payment_hash {}", log_bytes!(payment_hash.0));
1599                                 mem::drop(channel_state_lock);
1600                                 match &onion_error {
1601                                         &HTLCFailReason::LightningError { ref err } => {
1602 #[cfg(test)]
1603                                                 let (channel_update, payment_retryable, onion_error_code) = onion_utils::process_onion_failure(&self.secp_ctx, &self.logger, &source, err.data.clone());
1604 #[cfg(not(test))]
1605                                                 let (channel_update, payment_retryable, _) = onion_utils::process_onion_failure(&self.secp_ctx, &self.logger, &source, err.data.clone());
1606                                                 // TODO: If we decided to blame ourselves (or one of our channels) in
1607                                                 // process_onion_failure we should close that channel as it implies our
1608                                                 // next-hop is needlessly blaming us!
1609                                                 if let Some(update) = channel_update {
1610                                                         self.channel_state.lock().unwrap().pending_msg_events.push(
1611                                                                 events::MessageSendEvent::PaymentFailureNetworkUpdate {
1612                                                                         update,
1613                                                                 }
1614                                                         );
1615                                                 }
1616                                                 self.pending_events.lock().unwrap().push(
1617                                                         events::Event::PaymentFailed {
1618                                                                 payment_hash: payment_hash.clone(),
1619                                                                 rejected_by_dest: !payment_retryable,
1620 #[cfg(test)]
1621                                                                 error_code: onion_error_code
1622                                                         }
1623                                                 );
1624                                         },
1625                                         &HTLCFailReason::Reason {
1626 #[cfg(test)]
1627                                                         ref failure_code,
1628                                                         .. } => {
1629                                                 // we get a fail_malformed_htlc from the first hop
1630                                                 // TODO: We'd like to generate a PaymentFailureNetworkUpdate for temporary
1631                                                 // failures here, but that would be insufficient as Router::get_route
1632                                                 // generally ignores its view of our own channels as we provide them via
1633                                                 // ChannelDetails.
1634                                                 // TODO: For non-temporary failures, we really should be closing the
1635                                                 // channel here as we apparently can't relay through them anyway.
1636                                                 self.pending_events.lock().unwrap().push(
1637                                                         events::Event::PaymentFailed {
1638                                                                 payment_hash: payment_hash.clone(),
1639                                                                 rejected_by_dest: route.hops.len() == 1,
1640 #[cfg(test)]
1641                                                                 error_code: Some(*failure_code),
1642                                                         }
1643                                                 );
1644                                         }
1645                                 }
1646                         },
1647                         HTLCSource::PreviousHopData(HTLCPreviousHopData { short_channel_id, htlc_id, incoming_packet_shared_secret }) => {
1648                                 let err_packet = match onion_error {
1649                                         HTLCFailReason::Reason { failure_code, data } => {
1650                                                 log_trace!(self, "Failing HTLC with payment_hash {} backwards from us with code {}", log_bytes!(payment_hash.0), failure_code);
1651                                                 let packet = onion_utils::build_failure_packet(&incoming_packet_shared_secret, failure_code, &data[..]).encode();
1652                                                 onion_utils::encrypt_failure_packet(&incoming_packet_shared_secret, &packet)
1653                                         },
1654                                         HTLCFailReason::LightningError { err } => {
1655                                                 log_trace!(self, "Failing HTLC with payment_hash {} backwards with pre-built LightningError", log_bytes!(payment_hash.0));
1656                                                 onion_utils::encrypt_failure_packet(&incoming_packet_shared_secret, &err.data)
1657                                         }
1658                                 };
1659
1660                                 let mut forward_event = None;
1661                                 if channel_state_lock.forward_htlcs.is_empty() {
1662                                         forward_event = Some(Duration::from_millis(MIN_HTLC_RELAY_HOLDING_CELL_MILLIS));
1663                                 }
1664                                 match channel_state_lock.forward_htlcs.entry(short_channel_id) {
1665                                         hash_map::Entry::Occupied(mut entry) => {
1666                                                 entry.get_mut().push(HTLCForwardInfo::FailHTLC { htlc_id, err_packet });
1667                                         },
1668                                         hash_map::Entry::Vacant(entry) => {
1669                                                 entry.insert(vec!(HTLCForwardInfo::FailHTLC { htlc_id, err_packet }));
1670                                         }
1671                                 }
1672                                 mem::drop(channel_state_lock);
1673                                 if let Some(time) = forward_event {
1674                                         let mut pending_events = self.pending_events.lock().unwrap();
1675                                         pending_events.push(events::Event::PendingHTLCsForwardable {
1676                                                 time_forwardable: time
1677                                         });
1678                                 }
1679                         },
1680                 }
1681         }
1682
1683         /// Provides a payment preimage in response to a PaymentReceived event, returning true and
1684         /// generating message events for the net layer to claim the payment, if possible. Thus, you
1685         /// should probably kick the net layer to go send messages if this returns true!
1686         ///
1687         /// You must specify the expected amounts for this HTLC, and we will only claim HTLCs
1688         /// available within a few percent of the expected amount. This is critical for several
1689         /// reasons : a) it avoids providing senders with `proof-of-payment` (in the form of the
1690         /// payment_preimage without having provided the full value and b) it avoids certain
1691         /// privacy-breaking recipient-probing attacks which may reveal payment activity to
1692         /// motivated attackers.
1693         ///
1694         /// May panic if called except in response to a PaymentReceived event.
1695         pub fn claim_funds(&self, payment_preimage: PaymentPreimage, expected_amount: u64) -> bool {
1696                 let payment_hash = PaymentHash(Sha256::hash(&payment_preimage.0).into_inner());
1697
1698                 let _ = self.total_consistency_lock.read().unwrap();
1699
1700                 let mut channel_state = Some(self.channel_state.lock().unwrap());
1701                 let removed_source = channel_state.as_mut().unwrap().claimable_htlcs.remove(&payment_hash);
1702                 if let Some(mut sources) = removed_source {
1703                         for (received_amount, htlc_with_hash) in sources.drain(..) {
1704                                 if channel_state.is_none() { channel_state = Some(self.channel_state.lock().unwrap()); }
1705                                 if received_amount < expected_amount || received_amount > expected_amount * 2 {
1706                                         let mut htlc_msat_data = byte_utils::be64_to_array(received_amount).to_vec();
1707                                         let mut height_data = byte_utils::be32_to_array(self.latest_block_height.load(Ordering::Acquire) as u32).to_vec();
1708                                         htlc_msat_data.append(&mut height_data);
1709                                         self.fail_htlc_backwards_internal(channel_state.take().unwrap(),
1710                                                                          HTLCSource::PreviousHopData(htlc_with_hash), &payment_hash,
1711                                                                          HTLCFailReason::Reason { failure_code: 0x4000|15, data: htlc_msat_data });
1712                                 } else {
1713                                         self.claim_funds_internal(channel_state.take().unwrap(), HTLCSource::PreviousHopData(htlc_with_hash), payment_preimage);
1714                                 }
1715                         }
1716                         true
1717                 } else { false }
1718         }
1719         fn claim_funds_internal(&self, mut channel_state_lock: MutexGuard<ChannelHolder<ChanSigner>>, source: HTLCSource, payment_preimage: PaymentPreimage) {
1720                 let (their_node_id, err) = loop {
1721                         match source {
1722                                 HTLCSource::OutboundRoute { .. } => {
1723                                         mem::drop(channel_state_lock);
1724                                         let mut pending_events = self.pending_events.lock().unwrap();
1725                                         pending_events.push(events::Event::PaymentSent {
1726                                                 payment_preimage
1727                                         });
1728                                 },
1729                                 HTLCSource::PreviousHopData(HTLCPreviousHopData { short_channel_id, htlc_id, .. }) => {
1730                                         //TODO: Delay the claimed_funds relaying just like we do outbound relay!
1731                                         let channel_state = &mut *channel_state_lock;
1732
1733                                         let chan_id = match channel_state.short_to_id.get(&short_channel_id) {
1734                                                 Some(chan_id) => chan_id.clone(),
1735                                                 None => {
1736                                                         // TODO: There is probably a channel manager somewhere that needs to
1737                                                         // learn the preimage as the channel already hit the chain and that's
1738                                                         // why it's missing.
1739                                                         return
1740                                                 }
1741                                         };
1742
1743                                         if let hash_map::Entry::Occupied(mut chan) = channel_state.by_id.entry(chan_id) {
1744                                                 let was_frozen_for_monitor = chan.get().is_awaiting_monitor_update();
1745                                                 match chan.get_mut().get_update_fulfill_htlc_and_commit(htlc_id, payment_preimage) {
1746                                                         Ok((msgs, monitor_option)) => {
1747                                                                 if let Some(monitor_update) = monitor_option {
1748                                                                         if let Err(e) = self.monitor.update_monitor(chan.get().get_funding_txo().unwrap(), monitor_update) {
1749                                                                                 if was_frozen_for_monitor {
1750                                                                                         assert!(msgs.is_none());
1751                                                                                 } else {
1752                                                                                         break (chan.get().get_their_node_id(), handle_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::CommitmentFirst, false, msgs.is_some()));
1753                                                                                 }
1754                                                                         }
1755                                                                 }
1756                                                                 if let Some((msg, commitment_signed)) = msgs {
1757                                                                         channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
1758                                                                                 node_id: chan.get().get_their_node_id(),
1759                                                                                 updates: msgs::CommitmentUpdate {
1760                                                                                         update_add_htlcs: Vec::new(),
1761                                                                                         update_fulfill_htlcs: vec![msg],
1762                                                                                         update_fail_htlcs: Vec::new(),
1763                                                                                         update_fail_malformed_htlcs: Vec::new(),
1764                                                                                         update_fee: None,
1765                                                                                         commitment_signed,
1766                                                                                 }
1767                                                                         });
1768                                                                 }
1769                                                         },
1770                                                         Err(_e) => {
1771                                                                 // TODO: There is probably a channel manager somewhere that needs to
1772                                                                 // learn the preimage as the channel may be about to hit the chain.
1773                                                                 //TODO: Do something with e?
1774                                                                 return
1775                                                         },
1776                                                 }
1777                                         } else { unreachable!(); }
1778                                 },
1779                         }
1780                         return;
1781                 };
1782
1783                 let _ = handle_error!(self, err, their_node_id, channel_state_lock);
1784         }
1785
1786         /// Gets the node_id held by this ChannelManager
1787         pub fn get_our_node_id(&self) -> PublicKey {
1788                 PublicKey::from_secret_key(&self.secp_ctx, &self.our_network_key)
1789         }
1790
1791         /// Restores a single, given channel to normal operation after a
1792         /// ChannelMonitorUpdateErr::TemporaryFailure was returned from a channel monitor update
1793         /// operation.
1794         ///
1795         /// All ChannelMonitor updates up to and including highest_applied_update_id must have been
1796         /// fully committed in every copy of the given channels' ChannelMonitors.
1797         ///
1798         /// Note that there is no effect to calling with a highest_applied_update_id other than the
1799         /// current latest ChannelMonitorUpdate and one call to this function after multiple
1800         /// ChannelMonitorUpdateErr::TemporaryFailures is fine. The highest_applied_update_id field
1801         /// exists largely only to prevent races between this and concurrent update_monitor calls.
1802         ///
1803         /// Thus, the anticipated use is, at a high level:
1804         ///  1) You register a ManyChannelMonitor with this ChannelManager,
1805         ///  2) it stores each update to disk, and begins updating any remote (eg watchtower) copies of
1806         ///     said ChannelMonitors as it can, returning ChannelMonitorUpdateErr::TemporaryFailures
1807         ///     any time it cannot do so instantly,
1808         ///  3) update(s) are applied to each remote copy of a ChannelMonitor,
1809         ///  4) once all remote copies are updated, you call this function with the update_id that
1810         ///     completed, and once it is the latest the Channel will be re-enabled.
1811         pub fn channel_monitor_updated(&self, funding_txo: &OutPoint, highest_applied_update_id: u64) {
1812                 let _ = self.total_consistency_lock.read().unwrap();
1813
1814                 let mut close_results = Vec::new();
1815                 let mut htlc_forwards = Vec::new();
1816                 let mut htlc_failures = Vec::new();
1817                 let mut pending_events = Vec::new();
1818
1819                 {
1820                         let mut channel_lock = self.channel_state.lock().unwrap();
1821                         let channel_state = &mut *channel_lock;
1822                         let short_to_id = &mut channel_state.short_to_id;
1823                         let pending_msg_events = &mut channel_state.pending_msg_events;
1824                         let channel = match channel_state.by_id.get_mut(&funding_txo.to_channel_id()) {
1825                                 Some(chan) => chan,
1826                                 None => return,
1827                         };
1828                         if !channel.is_awaiting_monitor_update() || channel.get_latest_monitor_update_id() != highest_applied_update_id {
1829                                 return;
1830                         }
1831
1832                         let (raa, commitment_update, order, pending_forwards, mut pending_failures, needs_broadcast_safe, funding_locked) = channel.monitor_updating_restored();
1833                         if !pending_forwards.is_empty() {
1834                                 htlc_forwards.push((channel.get_short_channel_id().expect("We can't have pending forwards before funding confirmation"), pending_forwards));
1835                         }
1836                         htlc_failures.append(&mut pending_failures);
1837
1838                         macro_rules! handle_cs { () => {
1839                                 if let Some(update) = commitment_update {
1840                                         pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
1841                                                 node_id: channel.get_their_node_id(),
1842                                                 updates: update,
1843                                         });
1844                                 }
1845                         } }
1846                         macro_rules! handle_raa { () => {
1847                                 if let Some(revoke_and_ack) = raa {
1848                                         pending_msg_events.push(events::MessageSendEvent::SendRevokeAndACK {
1849                                                 node_id: channel.get_their_node_id(),
1850                                                 msg: revoke_and_ack,
1851                                         });
1852                                 }
1853                         } }
1854                         match order {
1855                                 RAACommitmentOrder::CommitmentFirst => {
1856                                         handle_cs!();
1857                                         handle_raa!();
1858                                 },
1859                                 RAACommitmentOrder::RevokeAndACKFirst => {
1860                                         handle_raa!();
1861                                         handle_cs!();
1862                                 },
1863                         }
1864                         if needs_broadcast_safe {
1865                                 pending_events.push(events::Event::FundingBroadcastSafe {
1866                                         funding_txo: channel.get_funding_txo().unwrap(),
1867                                         user_channel_id: channel.get_user_id(),
1868                                 });
1869                         }
1870                         if let Some(msg) = funding_locked {
1871                                 pending_msg_events.push(events::MessageSendEvent::SendFundingLocked {
1872                                         node_id: channel.get_their_node_id(),
1873                                         msg,
1874                                 });
1875                                 if let Some(announcement_sigs) = self.get_announcement_sigs(channel) {
1876                                         pending_msg_events.push(events::MessageSendEvent::SendAnnouncementSignatures {
1877                                                 node_id: channel.get_their_node_id(),
1878                                                 msg: announcement_sigs,
1879                                         });
1880                                 }
1881                                 short_to_id.insert(channel.get_short_channel_id().unwrap(), channel.channel_id());
1882                         }
1883                 }
1884
1885                 self.pending_events.lock().unwrap().append(&mut pending_events);
1886
1887                 for failure in htlc_failures.drain(..) {
1888                         self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), failure.0, &failure.1, failure.2);
1889                 }
1890                 self.forward_htlcs(&mut htlc_forwards[..]);
1891
1892                 for res in close_results.drain(..) {
1893                         self.finish_force_close_channel(res);
1894                 }
1895         }
1896
1897         fn internal_open_channel(&self, their_node_id: &PublicKey, their_features: InitFeatures, msg: &msgs::OpenChannel) -> Result<(), MsgHandleErrInternal> {
1898                 if msg.chain_hash != self.genesis_hash {
1899                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Unknown genesis block hash", msg.temporary_channel_id.clone()));
1900                 }
1901
1902                 let channel = Channel::new_from_req(&self.fee_estimator, &self.keys_manager, their_node_id.clone(), their_features, msg, 0, Arc::clone(&self.logger), &self.default_configuration)
1903                         .map_err(|e| MsgHandleErrInternal::from_chan_no_close(e, msg.temporary_channel_id))?;
1904                 let mut channel_state_lock = self.channel_state.lock().unwrap();
1905                 let channel_state = &mut *channel_state_lock;
1906                 match channel_state.by_id.entry(channel.channel_id()) {
1907                         hash_map::Entry::Occupied(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("temporary_channel_id collision!", msg.temporary_channel_id.clone())),
1908                         hash_map::Entry::Vacant(entry) => {
1909                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendAcceptChannel {
1910                                         node_id: their_node_id.clone(),
1911                                         msg: channel.get_accept_channel(),
1912                                 });
1913                                 entry.insert(channel);
1914                         }
1915                 }
1916                 Ok(())
1917         }
1918
1919         fn internal_accept_channel(&self, their_node_id: &PublicKey, their_features: InitFeatures, msg: &msgs::AcceptChannel) -> Result<(), MsgHandleErrInternal> {
1920                 let (value, output_script, user_id) = {
1921                         let mut channel_lock = self.channel_state.lock().unwrap();
1922                         let channel_state = &mut *channel_lock;
1923                         match channel_state.by_id.entry(msg.temporary_channel_id) {
1924                                 hash_map::Entry::Occupied(mut chan) => {
1925                                         if chan.get().get_their_node_id() != *their_node_id {
1926                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.temporary_channel_id));
1927                                         }
1928                                         try_chan_entry!(self, chan.get_mut().accept_channel(&msg, &self.default_configuration, their_features), channel_state, chan);
1929                                         (chan.get().get_value_satoshis(), chan.get().get_funding_redeemscript().to_v0_p2wsh(), chan.get().get_user_id())
1930                                 },
1931                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.temporary_channel_id))
1932                         }
1933                 };
1934                 let mut pending_events = self.pending_events.lock().unwrap();
1935                 pending_events.push(events::Event::FundingGenerationReady {
1936                         temporary_channel_id: msg.temporary_channel_id,
1937                         channel_value_satoshis: value,
1938                         output_script: output_script,
1939                         user_channel_id: user_id,
1940                 });
1941                 Ok(())
1942         }
1943
1944         fn internal_funding_created(&self, their_node_id: &PublicKey, msg: &msgs::FundingCreated) -> Result<(), MsgHandleErrInternal> {
1945                 let ((funding_msg, monitor_update), mut chan) = {
1946                         let mut channel_lock = self.channel_state.lock().unwrap();
1947                         let channel_state = &mut *channel_lock;
1948                         match channel_state.by_id.entry(msg.temporary_channel_id.clone()) {
1949                                 hash_map::Entry::Occupied(mut chan) => {
1950                                         if chan.get().get_their_node_id() != *their_node_id {
1951                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.temporary_channel_id));
1952                                         }
1953                                         (try_chan_entry!(self, chan.get_mut().funding_created(msg), channel_state, chan), chan.remove())
1954                                 },
1955                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.temporary_channel_id))
1956                         }
1957                 };
1958                 // Because we have exclusive ownership of the channel here we can release the channel_state
1959                 // lock before add_monitor
1960                 if let Err(e) = self.monitor.add_monitor(monitor_update.get_funding_txo().unwrap(), monitor_update) {
1961                         match e {
1962                                 ChannelMonitorUpdateErr::PermanentFailure => {
1963                                         // Note that we reply with the new channel_id in error messages if we gave up on the
1964                                         // channel, not the temporary_channel_id. This is compatible with ourselves, but the
1965                                         // spec is somewhat ambiguous here. Not a huge deal since we'll send error messages for
1966                                         // any messages referencing a previously-closed channel anyway.
1967                                         return Err(MsgHandleErrInternal::from_finish_shutdown("ChannelMonitor storage failure", funding_msg.channel_id, chan.force_shutdown(), None));
1968                                 },
1969                                 ChannelMonitorUpdateErr::TemporaryFailure => {
1970                                         // There's no problem signing a counterparty's funding transaction if our monitor
1971                                         // hasn't persisted to disk yet - we can't lose money on a transaction that we haven't
1972                                         // accepted payment from yet. We do, however, need to wait to send our funding_locked
1973                                         // until we have persisted our monitor.
1974                                         chan.monitor_update_failed(false, false, Vec::new(), Vec::new());
1975                                 },
1976                         }
1977                 }
1978                 let mut channel_state_lock = self.channel_state.lock().unwrap();
1979                 let channel_state = &mut *channel_state_lock;
1980                 match channel_state.by_id.entry(funding_msg.channel_id) {
1981                         hash_map::Entry::Occupied(_) => {
1982                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Already had channel with the new channel_id", funding_msg.channel_id))
1983                         },
1984                         hash_map::Entry::Vacant(e) => {
1985                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendFundingSigned {
1986                                         node_id: their_node_id.clone(),
1987                                         msg: funding_msg,
1988                                 });
1989                                 e.insert(chan);
1990                         }
1991                 }
1992                 Ok(())
1993         }
1994
1995         fn internal_funding_signed(&self, their_node_id: &PublicKey, msg: &msgs::FundingSigned) -> Result<(), MsgHandleErrInternal> {
1996                 let (funding_txo, user_id) = {
1997                         let mut channel_lock = self.channel_state.lock().unwrap();
1998                         let channel_state = &mut *channel_lock;
1999                         match channel_state.by_id.entry(msg.channel_id) {
2000                                 hash_map::Entry::Occupied(mut chan) => {
2001                                         if chan.get().get_their_node_id() != *their_node_id {
2002                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2003                                         }
2004                                         let monitor_update = match chan.get_mut().funding_signed(&msg) {
2005                                                 Err((None, e)) => try_chan_entry!(self, Err(e), channel_state, chan),
2006                                                 Err((Some(monitor_update), e)) => {
2007                                                         assert!(chan.get().is_awaiting_monitor_update());
2008                                                         let _ = self.monitor.update_monitor(chan.get().get_funding_txo().unwrap(), monitor_update);
2009                                                         try_chan_entry!(self, Err(e), channel_state, chan);
2010                                                         unreachable!();
2011                                                 },
2012                                                 Ok(update) => update,
2013                                         };
2014                                         if let Err(e) = self.monitor.update_monitor(chan.get().get_funding_txo().unwrap(), monitor_update) {
2015                                                 return_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::RevokeAndACKFirst, false, false);
2016                                         }
2017                                         (chan.get().get_funding_txo().unwrap(), chan.get().get_user_id())
2018                                 },
2019                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2020                         }
2021                 };
2022                 let mut pending_events = self.pending_events.lock().unwrap();
2023                 pending_events.push(events::Event::FundingBroadcastSafe {
2024                         funding_txo: funding_txo,
2025                         user_channel_id: user_id,
2026                 });
2027                 Ok(())
2028         }
2029
2030         fn internal_funding_locked(&self, their_node_id: &PublicKey, msg: &msgs::FundingLocked) -> Result<(), MsgHandleErrInternal> {
2031                 let mut channel_state_lock = self.channel_state.lock().unwrap();
2032                 let channel_state = &mut *channel_state_lock;
2033                 match channel_state.by_id.entry(msg.channel_id) {
2034                         hash_map::Entry::Occupied(mut chan) => {
2035                                 if chan.get().get_their_node_id() != *their_node_id {
2036                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2037                                 }
2038                                 try_chan_entry!(self, chan.get_mut().funding_locked(&msg), channel_state, chan);
2039                                 if let Some(announcement_sigs) = self.get_announcement_sigs(chan.get()) {
2040                                         log_trace!(self, "Sending announcement_signatures for {} in response to funding_locked", log_bytes!(chan.get().channel_id()));
2041                                         // If we see locking block before receiving remote funding_locked, we broadcast our
2042                                         // announcement_sigs at remote funding_locked reception. If we receive remote
2043                                         // funding_locked before seeing locking block, we broadcast our announcement_sigs at locking
2044                                         // block connection. We should guanrantee to broadcast announcement_sigs to our peer whatever
2045                                         // the order of the events but our peer may not receive it due to disconnection. The specs
2046                                         // lacking an acknowledgement for announcement_sigs we may have to re-send them at peer
2047                                         // connection in the future if simultaneous misses by both peers due to network/hardware
2048                                         // failures is an issue. Note, to achieve its goal, only one of the announcement_sigs needs
2049                                         // to be received, from then sigs are going to be flood to the whole network.
2050                                         channel_state.pending_msg_events.push(events::MessageSendEvent::SendAnnouncementSignatures {
2051                                                 node_id: their_node_id.clone(),
2052                                                 msg: announcement_sigs,
2053                                         });
2054                                 }
2055                                 Ok(())
2056                         },
2057                         hash_map::Entry::Vacant(_) => Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2058                 }
2059         }
2060
2061         fn internal_shutdown(&self, their_node_id: &PublicKey, msg: &msgs::Shutdown) -> Result<(), MsgHandleErrInternal> {
2062                 let (mut dropped_htlcs, chan_option) = {
2063                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2064                         let channel_state = &mut *channel_state_lock;
2065
2066                         match channel_state.by_id.entry(msg.channel_id.clone()) {
2067                                 hash_map::Entry::Occupied(mut chan_entry) => {
2068                                         if chan_entry.get().get_their_node_id() != *their_node_id {
2069                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2070                                         }
2071                                         let (shutdown, closing_signed, dropped_htlcs) = try_chan_entry!(self, chan_entry.get_mut().shutdown(&self.fee_estimator, &msg), channel_state, chan_entry);
2072                                         if let Some(msg) = shutdown {
2073                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendShutdown {
2074                                                         node_id: their_node_id.clone(),
2075                                                         msg,
2076                                                 });
2077                                         }
2078                                         if let Some(msg) = closing_signed {
2079                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendClosingSigned {
2080                                                         node_id: their_node_id.clone(),
2081                                                         msg,
2082                                                 });
2083                                         }
2084                                         if chan_entry.get().is_shutdown() {
2085                                                 if let Some(short_id) = chan_entry.get().get_short_channel_id() {
2086                                                         channel_state.short_to_id.remove(&short_id);
2087                                                 }
2088                                                 (dropped_htlcs, Some(chan_entry.remove_entry().1))
2089                                         } else { (dropped_htlcs, None) }
2090                                 },
2091                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2092                         }
2093                 };
2094                 for htlc_source in dropped_htlcs.drain(..) {
2095                         self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), htlc_source.0, &htlc_source.1, HTLCFailReason::Reason { failure_code: 0x4000 | 8, data: Vec::new() });
2096                 }
2097                 if let Some(chan) = chan_option {
2098                         if let Ok(update) = self.get_channel_update(&chan) {
2099                                 let mut channel_state = self.channel_state.lock().unwrap();
2100                                 channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
2101                                         msg: update
2102                                 });
2103                         }
2104                 }
2105                 Ok(())
2106         }
2107
2108         fn internal_closing_signed(&self, their_node_id: &PublicKey, msg: &msgs::ClosingSigned) -> Result<(), MsgHandleErrInternal> {
2109                 let (tx, chan_option) = {
2110                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2111                         let channel_state = &mut *channel_state_lock;
2112                         match channel_state.by_id.entry(msg.channel_id.clone()) {
2113                                 hash_map::Entry::Occupied(mut chan_entry) => {
2114                                         if chan_entry.get().get_their_node_id() != *their_node_id {
2115                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2116                                         }
2117                                         let (closing_signed, tx) = try_chan_entry!(self, chan_entry.get_mut().closing_signed(&self.fee_estimator, &msg), channel_state, chan_entry);
2118                                         if let Some(msg) = closing_signed {
2119                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendClosingSigned {
2120                                                         node_id: their_node_id.clone(),
2121                                                         msg,
2122                                                 });
2123                                         }
2124                                         if tx.is_some() {
2125                                                 // We're done with this channel, we've got a signed closing transaction and
2126                                                 // will send the closing_signed back to the remote peer upon return. This
2127                                                 // also implies there are no pending HTLCs left on the channel, so we can
2128                                                 // fully delete it from tracking (the channel monitor is still around to
2129                                                 // watch for old state broadcasts)!
2130                                                 if let Some(short_id) = chan_entry.get().get_short_channel_id() {
2131                                                         channel_state.short_to_id.remove(&short_id);
2132                                                 }
2133                                                 (tx, Some(chan_entry.remove_entry().1))
2134                                         } else { (tx, None) }
2135                                 },
2136                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2137                         }
2138                 };
2139                 if let Some(broadcast_tx) = tx {
2140                         log_trace!(self, "Broadcast onchain {}", log_tx!(broadcast_tx));
2141                         self.tx_broadcaster.broadcast_transaction(&broadcast_tx);
2142                 }
2143                 if let Some(chan) = chan_option {
2144                         if let Ok(update) = self.get_channel_update(&chan) {
2145                                 let mut channel_state = self.channel_state.lock().unwrap();
2146                                 channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
2147                                         msg: update
2148                                 });
2149                         }
2150                 }
2151                 Ok(())
2152         }
2153
2154         fn internal_update_add_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateAddHTLC) -> Result<(), MsgHandleErrInternal> {
2155                 //TODO: BOLT 4 points out a specific attack where a peer may re-send an onion packet and
2156                 //determine the state of the payment based on our response/if we forward anything/the time
2157                 //we take to respond. We should take care to avoid allowing such an attack.
2158                 //
2159                 //TODO: There exists a further attack where a node may garble the onion data, forward it to
2160                 //us repeatedly garbled in different ways, and compare our error messages, which are
2161                 //encrypted with the same key. It's not immediately obvious how to usefully exploit that,
2162                 //but we should prevent it anyway.
2163
2164                 let (mut pending_forward_info, mut channel_state_lock) = self.decode_update_add_htlc_onion(msg);
2165                 let channel_state = &mut *channel_state_lock;
2166
2167                 match channel_state.by_id.entry(msg.channel_id) {
2168                         hash_map::Entry::Occupied(mut chan) => {
2169                                 if chan.get().get_their_node_id() != *their_node_id {
2170                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2171                                 }
2172                                 if !chan.get().is_usable() {
2173                                         // If the update_add is completely bogus, the call will Err and we will close,
2174                                         // but if we've sent a shutdown and they haven't acknowledged it yet, we just
2175                                         // want to reject the new HTLC and fail it backwards instead of forwarding.
2176                                         if let PendingHTLCStatus::Forward(PendingHTLCInfo { incoming_shared_secret, .. }) = pending_forward_info {
2177                                                 let chan_update = self.get_channel_update(chan.get());
2178                                                 pending_forward_info = PendingHTLCStatus::Fail(HTLCFailureMsg::Relay(msgs::UpdateFailHTLC {
2179                                                         channel_id: msg.channel_id,
2180                                                         htlc_id: msg.htlc_id,
2181                                                         reason: if let Ok(update) = chan_update {
2182                                                                 // TODO: Note that |20 is defined as "channel FROM the processing
2183                                                                 // node has been disabled" (emphasis mine), which seems to imply
2184                                                                 // that we can't return |20 for an inbound channel being disabled.
2185                                                                 // This probably needs a spec update but should definitely be
2186                                                                 // allowed.
2187                                                                 onion_utils::build_first_hop_failure_packet(&incoming_shared_secret, 0x1000|20, &{
2188                                                                         let mut res = Vec::with_capacity(8 + 128);
2189                                                                         res.extend_from_slice(&byte_utils::be16_to_array(update.contents.flags));
2190                                                                         res.extend_from_slice(&update.encode_with_len()[..]);
2191                                                                         res
2192                                                                 }[..])
2193                                                         } else {
2194                                                                 // This can only happen if the channel isn't in the fully-funded
2195                                                                 // state yet, implying our counterparty is trying to route payments
2196                                                                 // over the channel back to themselves (cause no one else should
2197                                                                 // know the short_id is a lightning channel yet). We should have no
2198                                                                 // problem just calling this unknown_next_peer
2199                                                                 onion_utils::build_first_hop_failure_packet(&incoming_shared_secret, 0x4000|10, &[])
2200                                                         },
2201                                                 }));
2202                                         }
2203                                 }
2204                                 try_chan_entry!(self, chan.get_mut().update_add_htlc(&msg, pending_forward_info), channel_state, chan);
2205                         },
2206                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2207                 }
2208                 Ok(())
2209         }
2210
2211         fn internal_update_fulfill_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFulfillHTLC) -> Result<(), MsgHandleErrInternal> {
2212                 let mut channel_lock = self.channel_state.lock().unwrap();
2213                 let htlc_source = {
2214                         let channel_state = &mut *channel_lock;
2215                         match channel_state.by_id.entry(msg.channel_id) {
2216                                 hash_map::Entry::Occupied(mut chan) => {
2217                                         if chan.get().get_their_node_id() != *their_node_id {
2218                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2219                                         }
2220                                         try_chan_entry!(self, chan.get_mut().update_fulfill_htlc(&msg), channel_state, chan)
2221                                 },
2222                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2223                         }
2224                 };
2225                 self.claim_funds_internal(channel_lock, htlc_source, msg.payment_preimage.clone());
2226                 Ok(())
2227         }
2228
2229         fn internal_update_fail_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFailHTLC) -> Result<(), MsgHandleErrInternal> {
2230                 let mut channel_lock = self.channel_state.lock().unwrap();
2231                 let channel_state = &mut *channel_lock;
2232                 match channel_state.by_id.entry(msg.channel_id) {
2233                         hash_map::Entry::Occupied(mut chan) => {
2234                                 if chan.get().get_their_node_id() != *their_node_id {
2235                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2236                                 }
2237                                 try_chan_entry!(self, chan.get_mut().update_fail_htlc(&msg, HTLCFailReason::LightningError { err: msg.reason.clone() }), channel_state, chan);
2238                         },
2239                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2240                 }
2241                 Ok(())
2242         }
2243
2244         fn internal_update_fail_malformed_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFailMalformedHTLC) -> Result<(), MsgHandleErrInternal> {
2245                 let mut channel_lock = self.channel_state.lock().unwrap();
2246                 let channel_state = &mut *channel_lock;
2247                 match channel_state.by_id.entry(msg.channel_id) {
2248                         hash_map::Entry::Occupied(mut chan) => {
2249                                 if chan.get().get_their_node_id() != *their_node_id {
2250                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2251                                 }
2252                                 if (msg.failure_code & 0x8000) == 0 {
2253                                         let chan_err: ChannelError = ChannelError::Close("Got update_fail_malformed_htlc with BADONION not set");
2254                                         try_chan_entry!(self, Err(chan_err), channel_state, chan);
2255                                 }
2256                                 try_chan_entry!(self, chan.get_mut().update_fail_malformed_htlc(&msg, HTLCFailReason::Reason { failure_code: msg.failure_code, data: Vec::new() }), channel_state, chan);
2257                                 Ok(())
2258                         },
2259                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2260                 }
2261         }
2262
2263         fn internal_commitment_signed(&self, their_node_id: &PublicKey, msg: &msgs::CommitmentSigned) -> Result<(), MsgHandleErrInternal> {
2264                 let mut channel_state_lock = self.channel_state.lock().unwrap();
2265                 let channel_state = &mut *channel_state_lock;
2266                 match channel_state.by_id.entry(msg.channel_id) {
2267                         hash_map::Entry::Occupied(mut chan) => {
2268                                 if chan.get().get_their_node_id() != *their_node_id {
2269                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2270                                 }
2271                                 let (revoke_and_ack, commitment_signed, closing_signed, monitor_update) =
2272                                                 match chan.get_mut().commitment_signed(&msg, &self.fee_estimator) {
2273                                         Err((None, e)) => try_chan_entry!(self, Err(e), channel_state, chan),
2274                                         Err((Some(update), e)) => {
2275                                                 assert!(chan.get().is_awaiting_monitor_update());
2276                                                 let _ = self.monitor.update_monitor(chan.get().get_funding_txo().unwrap(), update);
2277                                                 try_chan_entry!(self, Err(e), channel_state, chan);
2278                                                 unreachable!();
2279                                         },
2280                                         Ok(res) => res
2281                                 };
2282                                 if let Err(e) = self.monitor.update_monitor(chan.get().get_funding_txo().unwrap(), monitor_update) {
2283                                         return_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::RevokeAndACKFirst, true, commitment_signed.is_some());
2284                                         //TODO: Rebroadcast closing_signed if present on monitor update restoration
2285                                 }
2286                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendRevokeAndACK {
2287                                         node_id: their_node_id.clone(),
2288                                         msg: revoke_and_ack,
2289                                 });
2290                                 if let Some(msg) = commitment_signed {
2291                                         channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
2292                                                 node_id: their_node_id.clone(),
2293                                                 updates: msgs::CommitmentUpdate {
2294                                                         update_add_htlcs: Vec::new(),
2295                                                         update_fulfill_htlcs: Vec::new(),
2296                                                         update_fail_htlcs: Vec::new(),
2297                                                         update_fail_malformed_htlcs: Vec::new(),
2298                                                         update_fee: None,
2299                                                         commitment_signed: msg,
2300                                                 },
2301                                         });
2302                                 }
2303                                 if let Some(msg) = closing_signed {
2304                                         channel_state.pending_msg_events.push(events::MessageSendEvent::SendClosingSigned {
2305                                                 node_id: their_node_id.clone(),
2306                                                 msg,
2307                                         });
2308                                 }
2309                                 Ok(())
2310                         },
2311                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2312                 }
2313         }
2314
2315         #[inline]
2316         fn forward_htlcs(&self, per_source_pending_forwards: &mut [(u64, Vec<(PendingHTLCInfo, u64)>)]) {
2317                 for &mut (prev_short_channel_id, ref mut pending_forwards) in per_source_pending_forwards {
2318                         let mut forward_event = None;
2319                         if !pending_forwards.is_empty() {
2320                                 let mut channel_state = self.channel_state.lock().unwrap();
2321                                 if channel_state.forward_htlcs.is_empty() {
2322                                         forward_event = Some(Duration::from_millis(MIN_HTLC_RELAY_HOLDING_CELL_MILLIS))
2323                                 }
2324                                 for (forward_info, prev_htlc_id) in pending_forwards.drain(..) {
2325                                         match channel_state.forward_htlcs.entry(forward_info.short_channel_id) {
2326                                                 hash_map::Entry::Occupied(mut entry) => {
2327                                                         entry.get_mut().push(HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info });
2328                                                 },
2329                                                 hash_map::Entry::Vacant(entry) => {
2330                                                         entry.insert(vec!(HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info }));
2331                                                 }
2332                                         }
2333                                 }
2334                         }
2335                         match forward_event {
2336                                 Some(time) => {
2337                                         let mut pending_events = self.pending_events.lock().unwrap();
2338                                         pending_events.push(events::Event::PendingHTLCsForwardable {
2339                                                 time_forwardable: time
2340                                         });
2341                                 }
2342                                 None => {},
2343                         }
2344                 }
2345         }
2346
2347         fn internal_revoke_and_ack(&self, their_node_id: &PublicKey, msg: &msgs::RevokeAndACK) -> Result<(), MsgHandleErrInternal> {
2348                 let (pending_forwards, mut pending_failures, short_channel_id) = {
2349                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2350                         let channel_state = &mut *channel_state_lock;
2351                         match channel_state.by_id.entry(msg.channel_id) {
2352                                 hash_map::Entry::Occupied(mut chan) => {
2353                                         if chan.get().get_their_node_id() != *their_node_id {
2354                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2355                                         }
2356                                         let was_frozen_for_monitor = chan.get().is_awaiting_monitor_update();
2357                                         let (commitment_update, pending_forwards, pending_failures, closing_signed, monitor_update) =
2358                                                 try_chan_entry!(self, chan.get_mut().revoke_and_ack(&msg, &self.fee_estimator), channel_state, chan);
2359                                         if let Err(e) = self.monitor.update_monitor(chan.get().get_funding_txo().unwrap(), monitor_update) {
2360                                                 if was_frozen_for_monitor {
2361                                                         assert!(commitment_update.is_none() && closing_signed.is_none() && pending_forwards.is_empty() && pending_failures.is_empty());
2362                                                         return Err(MsgHandleErrInternal::ignore_no_close("Previous monitor update failure prevented responses to RAA"));
2363                                                 } else {
2364                                                         return_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::CommitmentFirst, false, commitment_update.is_some(), pending_forwards, pending_failures);
2365                                                 }
2366                                         }
2367                                         if let Some(updates) = commitment_update {
2368                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
2369                                                         node_id: their_node_id.clone(),
2370                                                         updates,
2371                                                 });
2372                                         }
2373                                         if let Some(msg) = closing_signed {
2374                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendClosingSigned {
2375                                                         node_id: their_node_id.clone(),
2376                                                         msg,
2377                                                 });
2378                                         }
2379                                         (pending_forwards, pending_failures, chan.get().get_short_channel_id().expect("RAA should only work on a short-id-available channel"))
2380                                 },
2381                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2382                         }
2383                 };
2384                 for failure in pending_failures.drain(..) {
2385                         self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), failure.0, &failure.1, failure.2);
2386                 }
2387                 self.forward_htlcs(&mut [(short_channel_id, pending_forwards)]);
2388
2389                 Ok(())
2390         }
2391
2392         fn internal_update_fee(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFee) -> Result<(), MsgHandleErrInternal> {
2393                 let mut channel_lock = self.channel_state.lock().unwrap();
2394                 let channel_state = &mut *channel_lock;
2395                 match channel_state.by_id.entry(msg.channel_id) {
2396                         hash_map::Entry::Occupied(mut chan) => {
2397                                 if chan.get().get_their_node_id() != *their_node_id {
2398                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2399                                 }
2400                                 try_chan_entry!(self, chan.get_mut().update_fee(&self.fee_estimator, &msg), channel_state, chan);
2401                         },
2402                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2403                 }
2404                 Ok(())
2405         }
2406
2407         fn internal_announcement_signatures(&self, their_node_id: &PublicKey, msg: &msgs::AnnouncementSignatures) -> Result<(), MsgHandleErrInternal> {
2408                 let mut channel_state_lock = self.channel_state.lock().unwrap();
2409                 let channel_state = &mut *channel_state_lock;
2410
2411                 match channel_state.by_id.entry(msg.channel_id) {
2412                         hash_map::Entry::Occupied(mut chan) => {
2413                                 if chan.get().get_their_node_id() != *their_node_id {
2414                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2415                                 }
2416                                 if !chan.get().is_usable() {
2417                                         return Err(MsgHandleErrInternal::from_no_close(LightningError{err: "Got an announcement_signatures before we were ready for it", action: msgs::ErrorAction::IgnoreError}));
2418                                 }
2419
2420                                 let our_node_id = self.get_our_node_id();
2421                                 let (announcement, our_bitcoin_sig) =
2422                                         try_chan_entry!(self, chan.get_mut().get_channel_announcement(our_node_id.clone(), self.genesis_hash.clone()), channel_state, chan);
2423
2424                                 let were_node_one = announcement.node_id_1 == our_node_id;
2425                                 let msghash = hash_to_message!(&Sha256dHash::hash(&announcement.encode()[..])[..]);
2426                                 if self.secp_ctx.verify(&msghash, &msg.node_signature, if were_node_one { &announcement.node_id_2 } else { &announcement.node_id_1 }).is_err() ||
2427                                                 self.secp_ctx.verify(&msghash, &msg.bitcoin_signature, if were_node_one { &announcement.bitcoin_key_2 } else { &announcement.bitcoin_key_1 }).is_err() {
2428                                         let chan_err: ChannelError = ChannelError::Close("Bad announcement_signatures node_signature");
2429                                         try_chan_entry!(self, Err(chan_err), channel_state, chan);
2430                                 }
2431
2432                                 let our_node_sig = self.secp_ctx.sign(&msghash, &self.our_network_key);
2433
2434                                 channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelAnnouncement {
2435                                         msg: msgs::ChannelAnnouncement {
2436                                                 node_signature_1: if were_node_one { our_node_sig } else { msg.node_signature },
2437                                                 node_signature_2: if were_node_one { msg.node_signature } else { our_node_sig },
2438                                                 bitcoin_signature_1: if were_node_one { our_bitcoin_sig } else { msg.bitcoin_signature },
2439                                                 bitcoin_signature_2: if were_node_one { msg.bitcoin_signature } else { our_bitcoin_sig },
2440                                                 contents: announcement,
2441                                         },
2442                                         update_msg: self.get_channel_update(chan.get()).unwrap(), // can only fail if we're not in a ready state
2443                                 });
2444                         },
2445                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2446                 }
2447                 Ok(())
2448         }
2449
2450         fn internal_channel_reestablish(&self, their_node_id: &PublicKey, msg: &msgs::ChannelReestablish) -> Result<(), MsgHandleErrInternal> {
2451                 let mut channel_state_lock = self.channel_state.lock().unwrap();
2452                 let channel_state = &mut *channel_state_lock;
2453
2454                 match channel_state.by_id.entry(msg.channel_id) {
2455                         hash_map::Entry::Occupied(mut chan) => {
2456                                 if chan.get().get_their_node_id() != *their_node_id {
2457                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2458                                 }
2459                                 let (funding_locked, revoke_and_ack, commitment_update, monitor_update_opt, mut order, shutdown) =
2460                                         try_chan_entry!(self, chan.get_mut().channel_reestablish(msg), channel_state, chan);
2461                                 if let Some(monitor_update) = monitor_update_opt {
2462                                         if let Err(e) = self.monitor.update_monitor(chan.get().get_funding_txo().unwrap(), monitor_update) {
2463                                                 // channel_reestablish doesn't guarantee the order it returns is sensical
2464                                                 // for the messages it returns, but if we're setting what messages to
2465                                                 // re-transmit on monitor update success, we need to make sure it is sane.
2466                                                 if revoke_and_ack.is_none() {
2467                                                         order = RAACommitmentOrder::CommitmentFirst;
2468                                                 }
2469                                                 if commitment_update.is_none() {
2470                                                         order = RAACommitmentOrder::RevokeAndACKFirst;
2471                                                 }
2472                                                 return_monitor_err!(self, e, channel_state, chan, order, revoke_and_ack.is_some(), commitment_update.is_some());
2473                                                 //TODO: Resend the funding_locked if needed once we get the monitor running again
2474                                         }
2475                                 }
2476                                 if let Some(msg) = funding_locked {
2477                                         channel_state.pending_msg_events.push(events::MessageSendEvent::SendFundingLocked {
2478                                                 node_id: their_node_id.clone(),
2479                                                 msg
2480                                         });
2481                                 }
2482                                 macro_rules! send_raa { () => {
2483                                         if let Some(msg) = revoke_and_ack {
2484                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendRevokeAndACK {
2485                                                         node_id: their_node_id.clone(),
2486                                                         msg
2487                                                 });
2488                                         }
2489                                 } }
2490                                 macro_rules! send_cu { () => {
2491                                         if let Some(updates) = commitment_update {
2492                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
2493                                                         node_id: their_node_id.clone(),
2494                                                         updates
2495                                                 });
2496                                         }
2497                                 } }
2498                                 match order {
2499                                         RAACommitmentOrder::RevokeAndACKFirst => {
2500                                                 send_raa!();
2501                                                 send_cu!();
2502                                         },
2503                                         RAACommitmentOrder::CommitmentFirst => {
2504                                                 send_cu!();
2505                                                 send_raa!();
2506                                         },
2507                                 }
2508                                 if let Some(msg) = shutdown {
2509                                         channel_state.pending_msg_events.push(events::MessageSendEvent::SendShutdown {
2510                                                 node_id: their_node_id.clone(),
2511                                                 msg,
2512                                         });
2513                                 }
2514                                 Ok(())
2515                         },
2516                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2517                 }
2518         }
2519
2520         /// Begin Update fee process. Allowed only on an outbound channel.
2521         /// If successful, will generate a UpdateHTLCs event, so you should probably poll
2522         /// PeerManager::process_events afterwards.
2523         /// Note: This API is likely to change!
2524         #[doc(hidden)]
2525         pub fn update_fee(&self, channel_id: [u8;32], feerate_per_kw: u64) -> Result<(), APIError> {
2526                 let _ = self.total_consistency_lock.read().unwrap();
2527                 let mut channel_state_lock = self.channel_state.lock().unwrap();
2528                 let their_node_id;
2529                 let err: Result<(), _> = loop {
2530                         let channel_state = &mut *channel_state_lock;
2531
2532                         match channel_state.by_id.entry(channel_id) {
2533                                 hash_map::Entry::Vacant(_) => return Err(APIError::APIMisuseError{err: "Failed to find corresponding channel"}),
2534                                 hash_map::Entry::Occupied(mut chan) => {
2535                                         if !chan.get().is_outbound() {
2536                                                 return Err(APIError::APIMisuseError{err: "update_fee cannot be sent for an inbound channel"});
2537                                         }
2538                                         if chan.get().is_awaiting_monitor_update() {
2539                                                 return Err(APIError::MonitorUpdateFailed);
2540                                         }
2541                                         if !chan.get().is_live() {
2542                                                 return Err(APIError::ChannelUnavailable{err: "Channel is either not yet fully established or peer is currently disconnected"});
2543                                         }
2544                                         their_node_id = chan.get().get_their_node_id();
2545                                         if let Some((update_fee, commitment_signed, monitor_update)) =
2546                                                         break_chan_entry!(self, chan.get_mut().send_update_fee_and_commit(feerate_per_kw), channel_state, chan)
2547                                         {
2548                                                 if let Err(_e) = self.monitor.update_monitor(chan.get().get_funding_txo().unwrap(), monitor_update) {
2549                                                         unimplemented!();
2550                                                 }
2551                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
2552                                                         node_id: chan.get().get_their_node_id(),
2553                                                         updates: msgs::CommitmentUpdate {
2554                                                                 update_add_htlcs: Vec::new(),
2555                                                                 update_fulfill_htlcs: Vec::new(),
2556                                                                 update_fail_htlcs: Vec::new(),
2557                                                                 update_fail_malformed_htlcs: Vec::new(),
2558                                                                 update_fee: Some(update_fee),
2559                                                                 commitment_signed,
2560                                                         },
2561                                                 });
2562                                         }
2563                                 },
2564                         }
2565                         return Ok(())
2566                 };
2567
2568                 match handle_error!(self, err, their_node_id, channel_state_lock) {
2569                         Ok(_) => unreachable!(),
2570                         Err(e) => { Err(APIError::APIMisuseError { err: e.err })}
2571                 }
2572         }
2573 }
2574
2575 impl<ChanSigner: ChannelKeys, M: Deref, T: Deref, K: Deref, F: Deref> events::MessageSendEventsProvider for ChannelManager<ChanSigner, M, T, K, F>
2576         where M::Target: ManyChannelMonitor<ChanSigner>,
2577         T::Target: BroadcasterInterface,
2578         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
2579         F::Target: FeeEstimator,
2580 {
2581         fn get_and_clear_pending_msg_events(&self) -> Vec<events::MessageSendEvent> {
2582                 // TODO: Event release to users and serialization is currently race-y: it's very easy for a
2583                 // user to serialize a ChannelManager with pending events in it and lose those events on
2584                 // restart. This is doubly true for the fail/fulfill-backs from monitor events!
2585                 {
2586                         //TODO: This behavior should be documented.
2587                         for htlc_update in self.monitor.get_and_clear_pending_htlcs_updated() {
2588                                 if let Some(preimage) = htlc_update.payment_preimage {
2589                                         log_trace!(self, "Claiming HTLC with preimage {} from our monitor", log_bytes!(preimage.0));
2590                                         self.claim_funds_internal(self.channel_state.lock().unwrap(), htlc_update.source, preimage);
2591                                 } else {
2592                                         log_trace!(self, "Failing HTLC with hash {} from our monitor", log_bytes!(htlc_update.payment_hash.0));
2593                                         self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), htlc_update.source, &htlc_update.payment_hash, HTLCFailReason::Reason { failure_code: 0x4000 | 8, data: Vec::new() });
2594                                 }
2595                         }
2596                 }
2597
2598                 let mut ret = Vec::new();
2599                 let mut channel_state = self.channel_state.lock().unwrap();
2600                 mem::swap(&mut ret, &mut channel_state.pending_msg_events);
2601                 ret
2602         }
2603 }
2604
2605 impl<ChanSigner: ChannelKeys, M: Deref, T: Deref, K: Deref, F: Deref> events::EventsProvider for ChannelManager<ChanSigner, M, T, K, F>
2606         where M::Target: ManyChannelMonitor<ChanSigner>,
2607         T::Target: BroadcasterInterface,
2608         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
2609         F::Target: FeeEstimator,
2610 {
2611         fn get_and_clear_pending_events(&self) -> Vec<events::Event> {
2612                 // TODO: Event release to users and serialization is currently race-y: it's very easy for a
2613                 // user to serialize a ChannelManager with pending events in it and lose those events on
2614                 // restart. This is doubly true for the fail/fulfill-backs from monitor events!
2615                 {
2616                         //TODO: This behavior should be documented.
2617                         for htlc_update in self.monitor.get_and_clear_pending_htlcs_updated() {
2618                                 if let Some(preimage) = htlc_update.payment_preimage {
2619                                         log_trace!(self, "Claiming HTLC with preimage {} from our monitor", log_bytes!(preimage.0));
2620                                         self.claim_funds_internal(self.channel_state.lock().unwrap(), htlc_update.source, preimage);
2621                                 } else {
2622                                         log_trace!(self, "Failing HTLC with hash {} from our monitor", log_bytes!(htlc_update.payment_hash.0));
2623                                         self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), htlc_update.source, &htlc_update.payment_hash, HTLCFailReason::Reason { failure_code: 0x4000 | 8, data: Vec::new() });
2624                                 }
2625                         }
2626                 }
2627
2628                 let mut ret = Vec::new();
2629                 let mut pending_events = self.pending_events.lock().unwrap();
2630                 mem::swap(&mut ret, &mut *pending_events);
2631                 ret
2632         }
2633 }
2634
2635 impl<ChanSigner: ChannelKeys, M: Deref + Sync + Send, T: Deref + Sync + Send, K: Deref + Sync + Send, F: Deref + Sync + Send>
2636         ChainListener for ChannelManager<ChanSigner, M, T, K, F>
2637         where M::Target: ManyChannelMonitor<ChanSigner>,
2638         T::Target: BroadcasterInterface,
2639         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
2640         F::Target: FeeEstimator,
2641 {
2642         fn block_connected(&self, header: &BlockHeader, height: u32, txn_matched: &[&Transaction], indexes_of_txn_matched: &[u32]) {
2643                 let header_hash = header.bitcoin_hash();
2644                 log_trace!(self, "Block {} at height {} connected with {} txn matched", header_hash, height, txn_matched.len());
2645                 let _ = self.total_consistency_lock.read().unwrap();
2646                 let mut failed_channels = Vec::new();
2647                 {
2648                         let mut channel_lock = self.channel_state.lock().unwrap();
2649                         let channel_state = &mut *channel_lock;
2650                         let short_to_id = &mut channel_state.short_to_id;
2651                         let pending_msg_events = &mut channel_state.pending_msg_events;
2652                         channel_state.by_id.retain(|_, channel| {
2653                                 let chan_res = channel.block_connected(header, height, txn_matched, indexes_of_txn_matched);
2654                                 if let Ok(Some(funding_locked)) = chan_res {
2655                                         pending_msg_events.push(events::MessageSendEvent::SendFundingLocked {
2656                                                 node_id: channel.get_their_node_id(),
2657                                                 msg: funding_locked,
2658                                         });
2659                                         if let Some(announcement_sigs) = self.get_announcement_sigs(channel) {
2660                                                 log_trace!(self, "Sending funding_locked and announcement_signatures for {}", log_bytes!(channel.channel_id()));
2661                                                 pending_msg_events.push(events::MessageSendEvent::SendAnnouncementSignatures {
2662                                                         node_id: channel.get_their_node_id(),
2663                                                         msg: announcement_sigs,
2664                                                 });
2665                                         } else {
2666                                                 log_trace!(self, "Sending funding_locked WITHOUT announcement_signatures for {}", log_bytes!(channel.channel_id()));
2667                                         }
2668                                         short_to_id.insert(channel.get_short_channel_id().unwrap(), channel.channel_id());
2669                                 } else if let Err(e) = chan_res {
2670                                         pending_msg_events.push(events::MessageSendEvent::HandleError {
2671                                                 node_id: channel.get_their_node_id(),
2672                                                 action: msgs::ErrorAction::SendErrorMessage { msg: e },
2673                                         });
2674                                         return false;
2675                                 }
2676                                 if let Some(funding_txo) = channel.get_funding_txo() {
2677                                         for tx in txn_matched {
2678                                                 for inp in tx.input.iter() {
2679                                                         if inp.previous_output == funding_txo.into_bitcoin_outpoint() {
2680                                                                 log_trace!(self, "Detected channel-closing tx {} spending {}:{}, closing channel {}", tx.txid(), inp.previous_output.txid, inp.previous_output.vout, log_bytes!(channel.channel_id()));
2681                                                                 if let Some(short_id) = channel.get_short_channel_id() {
2682                                                                         short_to_id.remove(&short_id);
2683                                                                 }
2684                                                                 // It looks like our counterparty went on-chain. We go ahead and
2685                                                                 // broadcast our latest local state as well here, just in case its
2686                                                                 // some kind of SPV attack, though we expect these to be dropped.
2687                                                                 failed_channels.push(channel.force_shutdown());
2688                                                                 if let Ok(update) = self.get_channel_update(&channel) {
2689                                                                         pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
2690                                                                                 msg: update
2691                                                                         });
2692                                                                 }
2693                                                                 return false;
2694                                                         }
2695                                                 }
2696                                         }
2697                                 }
2698                                 if channel.is_funding_initiated() && channel.channel_monitor().would_broadcast_at_height(height) {
2699                                         if let Some(short_id) = channel.get_short_channel_id() {
2700                                                 short_to_id.remove(&short_id);
2701                                         }
2702                                         failed_channels.push(channel.force_shutdown());
2703                                         // If would_broadcast_at_height() is true, the channel_monitor will broadcast
2704                                         // the latest local tx for us, so we should skip that here (it doesn't really
2705                                         // hurt anything, but does make tests a bit simpler).
2706                                         failed_channels.last_mut().unwrap().0 = Vec::new();
2707                                         if let Ok(update) = self.get_channel_update(&channel) {
2708                                                 pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
2709                                                         msg: update
2710                                                 });
2711                                         }
2712                                         return false;
2713                                 }
2714                                 true
2715                         });
2716                 }
2717                 for failure in failed_channels.drain(..) {
2718                         self.finish_force_close_channel(failure);
2719                 }
2720                 self.latest_block_height.store(height as usize, Ordering::Release);
2721                 *self.last_block_hash.try_lock().expect("block_(dis)connected must not be called in parallel") = header_hash;
2722         }
2723
2724         /// We force-close the channel without letting our counterparty participate in the shutdown
2725         fn block_disconnected(&self, header: &BlockHeader, _: u32) {
2726                 let _ = self.total_consistency_lock.read().unwrap();
2727                 let mut failed_channels = Vec::new();
2728                 {
2729                         let mut channel_lock = self.channel_state.lock().unwrap();
2730                         let channel_state = &mut *channel_lock;
2731                         let short_to_id = &mut channel_state.short_to_id;
2732                         let pending_msg_events = &mut channel_state.pending_msg_events;
2733                         channel_state.by_id.retain(|_,  v| {
2734                                 if v.block_disconnected(header) {
2735                                         if let Some(short_id) = v.get_short_channel_id() {
2736                                                 short_to_id.remove(&short_id);
2737                                         }
2738                                         failed_channels.push(v.force_shutdown());
2739                                         if let Ok(update) = self.get_channel_update(&v) {
2740                                                 pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
2741                                                         msg: update
2742                                                 });
2743                                         }
2744                                         false
2745                                 } else {
2746                                         true
2747                                 }
2748                         });
2749                 }
2750                 for failure in failed_channels.drain(..) {
2751                         self.finish_force_close_channel(failure);
2752                 }
2753                 self.latest_block_height.fetch_sub(1, Ordering::AcqRel);
2754                 *self.last_block_hash.try_lock().expect("block_(dis)connected must not be called in parallel") = header.bitcoin_hash();
2755         }
2756 }
2757
2758 impl<ChanSigner: ChannelKeys, M: Deref + Sync + Send, T: Deref + Sync + Send, K: Deref + Sync + Send, F: Deref + Sync + Send>
2759         ChannelMessageHandler for ChannelManager<ChanSigner, M, T, K, F>
2760         where M::Target: ManyChannelMonitor<ChanSigner>,
2761         T::Target: BroadcasterInterface,
2762         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
2763         F::Target: FeeEstimator,
2764 {
2765         fn handle_open_channel(&self, their_node_id: &PublicKey, their_features: InitFeatures, msg: &msgs::OpenChannel) {
2766                 let _ = self.total_consistency_lock.read().unwrap();
2767                 let res = self.internal_open_channel(their_node_id, their_features, msg);
2768                 if res.is_err() {
2769                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2770                         let _ = handle_error!(self, res, *their_node_id, channel_state_lock);
2771                 }
2772         }
2773
2774         fn handle_accept_channel(&self, their_node_id: &PublicKey, their_features: InitFeatures, msg: &msgs::AcceptChannel) {
2775                 let _ = self.total_consistency_lock.read().unwrap();
2776                 let res = self.internal_accept_channel(their_node_id, their_features, msg);
2777                 if res.is_err() {
2778                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2779                         let _ = handle_error!(self, res, *their_node_id, channel_state_lock);
2780                 }
2781         }
2782
2783         fn handle_funding_created(&self, their_node_id: &PublicKey, msg: &msgs::FundingCreated) {
2784                 let _ = self.total_consistency_lock.read().unwrap();
2785                 let res = self.internal_funding_created(their_node_id, msg);
2786                 if res.is_err() {
2787                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2788                         let _ = handle_error!(self, res, *their_node_id, channel_state_lock);
2789                 }
2790         }
2791
2792         fn handle_funding_signed(&self, their_node_id: &PublicKey, msg: &msgs::FundingSigned) {
2793                 let _ = self.total_consistency_lock.read().unwrap();
2794                 let res = self.internal_funding_signed(their_node_id, msg);
2795                 if res.is_err() {
2796                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2797                         let _ = handle_error!(self, res, *their_node_id, channel_state_lock);
2798                 }
2799         }
2800
2801         fn handle_funding_locked(&self, their_node_id: &PublicKey, msg: &msgs::FundingLocked) {
2802                 let _ = self.total_consistency_lock.read().unwrap();
2803                 let res = self.internal_funding_locked(their_node_id, msg);
2804                 if res.is_err() {
2805                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2806                         let _ = handle_error!(self, res, *their_node_id, channel_state_lock);
2807                 }
2808         }
2809
2810         fn handle_shutdown(&self, their_node_id: &PublicKey, msg: &msgs::Shutdown) {
2811                 let _ = self.total_consistency_lock.read().unwrap();
2812                 let res = self.internal_shutdown(their_node_id, msg);
2813                 if res.is_err() {
2814                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2815                         let _ = handle_error!(self, res, *their_node_id, channel_state_lock);
2816                 }
2817         }
2818
2819         fn handle_closing_signed(&self, their_node_id: &PublicKey, msg: &msgs::ClosingSigned) {
2820                 let _ = self.total_consistency_lock.read().unwrap();
2821                 let res = self.internal_closing_signed(their_node_id, msg);
2822                 if res.is_err() {
2823                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2824                         let _ = handle_error!(self, res, *their_node_id, channel_state_lock);
2825                 }
2826         }
2827
2828         fn handle_update_add_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateAddHTLC) {
2829                 let _ = self.total_consistency_lock.read().unwrap();
2830                 let res = self.internal_update_add_htlc(their_node_id, msg);
2831                 if res.is_err() {
2832                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2833                         let _ = handle_error!(self, res, *their_node_id, channel_state_lock);
2834                 }
2835         }
2836
2837         fn handle_update_fulfill_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFulfillHTLC) {
2838                 let _ = self.total_consistency_lock.read().unwrap();
2839                 let res = self.internal_update_fulfill_htlc(their_node_id, msg);
2840                 if res.is_err() {
2841                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2842                         let _ = handle_error!(self, res, *their_node_id, channel_state_lock);
2843                 }
2844         }
2845
2846         fn handle_update_fail_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFailHTLC) {
2847                 let _ = self.total_consistency_lock.read().unwrap();
2848                 let res = self.internal_update_fail_htlc(their_node_id, msg);
2849                 if res.is_err() {
2850                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2851                         let _ = handle_error!(self, res, *their_node_id, channel_state_lock);
2852                 }
2853         }
2854
2855         fn handle_update_fail_malformed_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFailMalformedHTLC) {
2856                 let _ = self.total_consistency_lock.read().unwrap();
2857                 let res = self.internal_update_fail_malformed_htlc(their_node_id, msg);
2858                 if res.is_err() {
2859                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2860                         let _ = handle_error!(self, res, *their_node_id, channel_state_lock);
2861                 }
2862         }
2863
2864         fn handle_commitment_signed(&self, their_node_id: &PublicKey, msg: &msgs::CommitmentSigned) {
2865                 let _ = self.total_consistency_lock.read().unwrap();
2866                 let res = self.internal_commitment_signed(their_node_id, msg);
2867                 if res.is_err() {
2868                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2869                         let _ = handle_error!(self, res, *their_node_id, channel_state_lock);
2870                 }
2871         }
2872
2873         fn handle_revoke_and_ack(&self, their_node_id: &PublicKey, msg: &msgs::RevokeAndACK) {
2874                 let _ = self.total_consistency_lock.read().unwrap();
2875                 let res = self.internal_revoke_and_ack(their_node_id, msg);
2876                 if res.is_err() {
2877                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2878                         let _ = handle_error!(self, res, *their_node_id, channel_state_lock);
2879                 }
2880         }
2881
2882         fn handle_update_fee(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFee) {
2883                 let _ = self.total_consistency_lock.read().unwrap();
2884                 let res = self.internal_update_fee(their_node_id, msg);
2885                 if res.is_err() {
2886                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2887                         let _ = handle_error!(self, res, *their_node_id, channel_state_lock);
2888                 }
2889         }
2890
2891         fn handle_announcement_signatures(&self, their_node_id: &PublicKey, msg: &msgs::AnnouncementSignatures) {
2892                 let _ = self.total_consistency_lock.read().unwrap();
2893                 let res = self.internal_announcement_signatures(their_node_id, msg);
2894                 if res.is_err() {
2895                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2896                         let _ = handle_error!(self, res, *their_node_id, channel_state_lock);
2897                 }
2898         }
2899
2900         fn handle_channel_reestablish(&self, their_node_id: &PublicKey, msg: &msgs::ChannelReestablish) {
2901                 let _ = self.total_consistency_lock.read().unwrap();
2902                 let res = self.internal_channel_reestablish(their_node_id, msg);
2903                 if res.is_err() {
2904                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2905                         let _ = handle_error!(self, res, *their_node_id, channel_state_lock);
2906                 }
2907         }
2908
2909         fn peer_disconnected(&self, their_node_id: &PublicKey, no_connection_possible: bool) {
2910                 let _ = self.total_consistency_lock.read().unwrap();
2911                 let mut failed_channels = Vec::new();
2912                 let mut failed_payments = Vec::new();
2913                 let mut no_channels_remain = true;
2914                 {
2915                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2916                         let channel_state = &mut *channel_state_lock;
2917                         let short_to_id = &mut channel_state.short_to_id;
2918                         let pending_msg_events = &mut channel_state.pending_msg_events;
2919                         if no_connection_possible {
2920                                 log_debug!(self, "Failing all channels with {} due to no_connection_possible", log_pubkey!(their_node_id));
2921                                 channel_state.by_id.retain(|_, chan| {
2922                                         if chan.get_their_node_id() == *their_node_id {
2923                                                 if let Some(short_id) = chan.get_short_channel_id() {
2924                                                         short_to_id.remove(&short_id);
2925                                                 }
2926                                                 failed_channels.push(chan.force_shutdown());
2927                                                 if let Ok(update) = self.get_channel_update(&chan) {
2928                                                         pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
2929                                                                 msg: update
2930                                                         });
2931                                                 }
2932                                                 false
2933                                         } else {
2934                                                 true
2935                                         }
2936                                 });
2937                         } else {
2938                                 log_debug!(self, "Marking channels with {} disconnected and generating channel_updates", log_pubkey!(their_node_id));
2939                                 channel_state.by_id.retain(|_, chan| {
2940                                         if chan.get_their_node_id() == *their_node_id {
2941                                                 let failed_adds = chan.remove_uncommitted_htlcs_and_mark_paused();
2942                                                 chan.to_disabled_marked();
2943                                                 if !failed_adds.is_empty() {
2944                                                         let chan_update = self.get_channel_update(&chan).map(|u| u.encode_with_len()).unwrap(); // Cannot add/recv HTLCs before we have a short_id so unwrap is safe
2945                                                         failed_payments.push((chan_update, failed_adds));
2946                                                 }
2947                                                 if chan.is_shutdown() {
2948                                                         if let Some(short_id) = chan.get_short_channel_id() {
2949                                                                 short_to_id.remove(&short_id);
2950                                                         }
2951                                                         return false;
2952                                                 } else {
2953                                                         no_channels_remain = false;
2954                                                 }
2955                                         }
2956                                         true
2957                                 })
2958                         }
2959                         pending_msg_events.retain(|msg| {
2960                                 match msg {
2961                                         &events::MessageSendEvent::SendAcceptChannel { ref node_id, .. } => node_id != their_node_id,
2962                                         &events::MessageSendEvent::SendOpenChannel { ref node_id, .. } => node_id != their_node_id,
2963                                         &events::MessageSendEvent::SendFundingCreated { ref node_id, .. } => node_id != their_node_id,
2964                                         &events::MessageSendEvent::SendFundingSigned { ref node_id, .. } => node_id != their_node_id,
2965                                         &events::MessageSendEvent::SendFundingLocked { ref node_id, .. } => node_id != their_node_id,
2966                                         &events::MessageSendEvent::SendAnnouncementSignatures { ref node_id, .. } => node_id != their_node_id,
2967                                         &events::MessageSendEvent::UpdateHTLCs { ref node_id, .. } => node_id != their_node_id,
2968                                         &events::MessageSendEvent::SendRevokeAndACK { ref node_id, .. } => node_id != their_node_id,
2969                                         &events::MessageSendEvent::SendClosingSigned { ref node_id, .. } => node_id != their_node_id,
2970                                         &events::MessageSendEvent::SendShutdown { ref node_id, .. } => node_id != their_node_id,
2971                                         &events::MessageSendEvent::SendChannelReestablish { ref node_id, .. } => node_id != their_node_id,
2972                                         &events::MessageSendEvent::BroadcastChannelAnnouncement { .. } => true,
2973                                         &events::MessageSendEvent::BroadcastChannelUpdate { .. } => true,
2974                                         &events::MessageSendEvent::HandleError { ref node_id, .. } => node_id != their_node_id,
2975                                         &events::MessageSendEvent::PaymentFailureNetworkUpdate { .. } => true,
2976                                 }
2977                         });
2978                 }
2979                 if no_channels_remain {
2980                         self.per_peer_state.write().unwrap().remove(their_node_id);
2981                 }
2982
2983                 for failure in failed_channels.drain(..) {
2984                         self.finish_force_close_channel(failure);
2985                 }
2986                 for (chan_update, mut htlc_sources) in failed_payments {
2987                         for (htlc_source, payment_hash) in htlc_sources.drain(..) {
2988                                 self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), htlc_source, &payment_hash, HTLCFailReason::Reason { failure_code: 0x1000 | 7, data: chan_update.clone() });
2989                         }
2990                 }
2991         }
2992
2993         fn peer_connected(&self, their_node_id: &PublicKey, init_msg: &msgs::Init) {
2994                 log_debug!(self, "Generating channel_reestablish events for {}", log_pubkey!(their_node_id));
2995
2996                 let _ = self.total_consistency_lock.read().unwrap();
2997
2998                 {
2999                         let mut peer_state_lock = self.per_peer_state.write().unwrap();
3000                         match peer_state_lock.entry(their_node_id.clone()) {
3001                                 hash_map::Entry::Vacant(e) => {
3002                                         e.insert(Mutex::new(PeerState {
3003                                                 latest_features: init_msg.features.clone(),
3004                                         }));
3005                                 },
3006                                 hash_map::Entry::Occupied(e) => {
3007                                         e.get().lock().unwrap().latest_features = init_msg.features.clone();
3008                                 },
3009                         }
3010                 }
3011
3012                 let mut channel_state_lock = self.channel_state.lock().unwrap();
3013                 let channel_state = &mut *channel_state_lock;
3014                 let pending_msg_events = &mut channel_state.pending_msg_events;
3015                 channel_state.by_id.retain(|_, chan| {
3016                         if chan.get_their_node_id() == *their_node_id {
3017                                 if !chan.have_received_message() {
3018                                         // If we created this (outbound) channel while we were disconnected from the
3019                                         // peer we probably failed to send the open_channel message, which is now
3020                                         // lost. We can't have had anything pending related to this channel, so we just
3021                                         // drop it.
3022                                         false
3023                                 } else {
3024                                         pending_msg_events.push(events::MessageSendEvent::SendChannelReestablish {
3025                                                 node_id: chan.get_their_node_id(),
3026                                                 msg: chan.get_channel_reestablish(),
3027                                         });
3028                                         true
3029                                 }
3030                         } else { true }
3031                 });
3032                 //TODO: Also re-broadcast announcement_signatures
3033         }
3034
3035         fn handle_error(&self, their_node_id: &PublicKey, msg: &msgs::ErrorMessage) {
3036                 let _ = self.total_consistency_lock.read().unwrap();
3037
3038                 if msg.channel_id == [0; 32] {
3039                         for chan in self.list_channels() {
3040                                 if chan.remote_network_id == *their_node_id {
3041                                         self.force_close_channel(&chan.channel_id);
3042                                 }
3043                         }
3044                 } else {
3045                         self.force_close_channel(&msg.channel_id);
3046                 }
3047         }
3048 }
3049
3050 const SERIALIZATION_VERSION: u8 = 1;
3051 const MIN_SERIALIZATION_VERSION: u8 = 1;
3052
3053 impl Writeable for PendingHTLCInfo {
3054         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3055                 self.onion_packet.write(writer)?;
3056                 self.incoming_shared_secret.write(writer)?;
3057                 self.payment_hash.write(writer)?;
3058                 self.short_channel_id.write(writer)?;
3059                 self.amt_to_forward.write(writer)?;
3060                 self.outgoing_cltv_value.write(writer)?;
3061                 Ok(())
3062         }
3063 }
3064
3065 impl<R: ::std::io::Read> Readable<R> for PendingHTLCInfo {
3066         fn read(reader: &mut R) -> Result<PendingHTLCInfo, DecodeError> {
3067                 Ok(PendingHTLCInfo {
3068                         onion_packet: Readable::read(reader)?,
3069                         incoming_shared_secret: Readable::read(reader)?,
3070                         payment_hash: Readable::read(reader)?,
3071                         short_channel_id: Readable::read(reader)?,
3072                         amt_to_forward: Readable::read(reader)?,
3073                         outgoing_cltv_value: Readable::read(reader)?,
3074                 })
3075         }
3076 }
3077
3078 impl Writeable for HTLCFailureMsg {
3079         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3080                 match self {
3081                         &HTLCFailureMsg::Relay(ref fail_msg) => {
3082                                 0u8.write(writer)?;
3083                                 fail_msg.write(writer)?;
3084                         },
3085                         &HTLCFailureMsg::Malformed(ref fail_msg) => {
3086                                 1u8.write(writer)?;
3087                                 fail_msg.write(writer)?;
3088                         }
3089                 }
3090                 Ok(())
3091         }
3092 }
3093
3094 impl<R: ::std::io::Read> Readable<R> for HTLCFailureMsg {
3095         fn read(reader: &mut R) -> Result<HTLCFailureMsg, DecodeError> {
3096                 match <u8 as Readable<R>>::read(reader)? {
3097                         0 => Ok(HTLCFailureMsg::Relay(Readable::read(reader)?)),
3098                         1 => Ok(HTLCFailureMsg::Malformed(Readable::read(reader)?)),
3099                         _ => Err(DecodeError::InvalidValue),
3100                 }
3101         }
3102 }
3103
3104 impl Writeable for PendingHTLCStatus {
3105         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3106                 match self {
3107                         &PendingHTLCStatus::Forward(ref forward_info) => {
3108                                 0u8.write(writer)?;
3109                                 forward_info.write(writer)?;
3110                         },
3111                         &PendingHTLCStatus::Fail(ref fail_msg) => {
3112                                 1u8.write(writer)?;
3113                                 fail_msg.write(writer)?;
3114                         }
3115                 }
3116                 Ok(())
3117         }
3118 }
3119
3120 impl<R: ::std::io::Read> Readable<R> for PendingHTLCStatus {
3121         fn read(reader: &mut R) -> Result<PendingHTLCStatus, DecodeError> {
3122                 match <u8 as Readable<R>>::read(reader)? {
3123                         0 => Ok(PendingHTLCStatus::Forward(Readable::read(reader)?)),
3124                         1 => Ok(PendingHTLCStatus::Fail(Readable::read(reader)?)),
3125                         _ => Err(DecodeError::InvalidValue),
3126                 }
3127         }
3128 }
3129
3130 impl_writeable!(HTLCPreviousHopData, 0, {
3131         short_channel_id,
3132         htlc_id,
3133         incoming_packet_shared_secret
3134 });
3135
3136 impl Writeable for HTLCSource {
3137         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3138                 match self {
3139                         &HTLCSource::PreviousHopData(ref hop_data) => {
3140                                 0u8.write(writer)?;
3141                                 hop_data.write(writer)?;
3142                         },
3143                         &HTLCSource::OutboundRoute { ref route, ref session_priv, ref first_hop_htlc_msat } => {
3144                                 1u8.write(writer)?;
3145                                 route.write(writer)?;
3146                                 session_priv.write(writer)?;
3147                                 first_hop_htlc_msat.write(writer)?;
3148                         }
3149                 }
3150                 Ok(())
3151         }
3152 }
3153
3154 impl<R: ::std::io::Read> Readable<R> for HTLCSource {
3155         fn read(reader: &mut R) -> Result<HTLCSource, DecodeError> {
3156                 match <u8 as Readable<R>>::read(reader)? {
3157                         0 => Ok(HTLCSource::PreviousHopData(Readable::read(reader)?)),
3158                         1 => Ok(HTLCSource::OutboundRoute {
3159                                 route: Readable::read(reader)?,
3160                                 session_priv: Readable::read(reader)?,
3161                                 first_hop_htlc_msat: Readable::read(reader)?,
3162                         }),
3163                         _ => Err(DecodeError::InvalidValue),
3164                 }
3165         }
3166 }
3167
3168 impl Writeable for HTLCFailReason {
3169         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3170                 match self {
3171                         &HTLCFailReason::LightningError { ref err } => {
3172                                 0u8.write(writer)?;
3173                                 err.write(writer)?;
3174                         },
3175                         &HTLCFailReason::Reason { ref failure_code, ref data } => {
3176                                 1u8.write(writer)?;
3177                                 failure_code.write(writer)?;
3178                                 data.write(writer)?;
3179                         }
3180                 }
3181                 Ok(())
3182         }
3183 }
3184
3185 impl<R: ::std::io::Read> Readable<R> for HTLCFailReason {
3186         fn read(reader: &mut R) -> Result<HTLCFailReason, DecodeError> {
3187                 match <u8 as Readable<R>>::read(reader)? {
3188                         0 => Ok(HTLCFailReason::LightningError { err: Readable::read(reader)? }),
3189                         1 => Ok(HTLCFailReason::Reason {
3190                                 failure_code: Readable::read(reader)?,
3191                                 data: Readable::read(reader)?,
3192                         }),
3193                         _ => Err(DecodeError::InvalidValue),
3194                 }
3195         }
3196 }
3197
3198 impl Writeable for HTLCForwardInfo {
3199         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3200                 match self {
3201                         &HTLCForwardInfo::AddHTLC { ref prev_short_channel_id, ref prev_htlc_id, ref forward_info } => {
3202                                 0u8.write(writer)?;
3203                                 prev_short_channel_id.write(writer)?;
3204                                 prev_htlc_id.write(writer)?;
3205                                 forward_info.write(writer)?;
3206                         },
3207                         &HTLCForwardInfo::FailHTLC { ref htlc_id, ref err_packet } => {
3208                                 1u8.write(writer)?;
3209                                 htlc_id.write(writer)?;
3210                                 err_packet.write(writer)?;
3211                         },
3212                 }
3213                 Ok(())
3214         }
3215 }
3216
3217 impl<R: ::std::io::Read> Readable<R> for HTLCForwardInfo {
3218         fn read(reader: &mut R) -> Result<HTLCForwardInfo, DecodeError> {
3219                 match <u8 as Readable<R>>::read(reader)? {
3220                         0 => Ok(HTLCForwardInfo::AddHTLC {
3221                                 prev_short_channel_id: Readable::read(reader)?,
3222                                 prev_htlc_id: Readable::read(reader)?,
3223                                 forward_info: Readable::read(reader)?,
3224                         }),
3225                         1 => Ok(HTLCForwardInfo::FailHTLC {
3226                                 htlc_id: Readable::read(reader)?,
3227                                 err_packet: Readable::read(reader)?,
3228                         }),
3229                         _ => Err(DecodeError::InvalidValue),
3230                 }
3231         }
3232 }
3233
3234 impl<ChanSigner: ChannelKeys + Writeable, M: Deref, T: Deref, K: Deref, F: Deref> Writeable for ChannelManager<ChanSigner, M, T, K, F>
3235         where M::Target: ManyChannelMonitor<ChanSigner>,
3236         T::Target: BroadcasterInterface,
3237         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
3238         F::Target: FeeEstimator,
3239 {
3240         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3241                 let _ = self.total_consistency_lock.write().unwrap();
3242
3243                 writer.write_all(&[SERIALIZATION_VERSION; 1])?;
3244                 writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
3245
3246                 self.genesis_hash.write(writer)?;
3247                 (self.latest_block_height.load(Ordering::Acquire) as u32).write(writer)?;
3248                 self.last_block_hash.lock().unwrap().write(writer)?;
3249
3250                 let channel_state = self.channel_state.lock().unwrap();
3251                 let mut unfunded_channels = 0;
3252                 for (_, channel) in channel_state.by_id.iter() {
3253                         if !channel.is_funding_initiated() {
3254                                 unfunded_channels += 1;
3255                         }
3256                 }
3257                 ((channel_state.by_id.len() - unfunded_channels) as u64).write(writer)?;
3258                 for (_, channel) in channel_state.by_id.iter() {
3259                         if channel.is_funding_initiated() {
3260                                 channel.write(writer)?;
3261                         }
3262                 }
3263
3264                 (channel_state.forward_htlcs.len() as u64).write(writer)?;
3265                 for (short_channel_id, pending_forwards) in channel_state.forward_htlcs.iter() {
3266                         short_channel_id.write(writer)?;
3267                         (pending_forwards.len() as u64).write(writer)?;
3268                         for forward in pending_forwards {
3269                                 forward.write(writer)?;
3270                         }
3271                 }
3272
3273                 (channel_state.claimable_htlcs.len() as u64).write(writer)?;
3274                 for (payment_hash, previous_hops) in channel_state.claimable_htlcs.iter() {
3275                         payment_hash.write(writer)?;
3276                         (previous_hops.len() as u64).write(writer)?;
3277                         for &(recvd_amt, ref previous_hop) in previous_hops.iter() {
3278                                 recvd_amt.write(writer)?;
3279                                 previous_hop.write(writer)?;
3280                         }
3281                 }
3282
3283                 let per_peer_state = self.per_peer_state.write().unwrap();
3284                 (per_peer_state.len() as u64).write(writer)?;
3285                 for (peer_pubkey, peer_state_mutex) in per_peer_state.iter() {
3286                         peer_pubkey.write(writer)?;
3287                         let peer_state = peer_state_mutex.lock().unwrap();
3288                         peer_state.latest_features.write(writer)?;
3289                 }
3290
3291                 Ok(())
3292         }
3293 }
3294
3295 /// Arguments for the creation of a ChannelManager that are not deserialized.
3296 ///
3297 /// At a high-level, the process for deserializing a ChannelManager and resuming normal operation
3298 /// is:
3299 /// 1) Deserialize all stored ChannelMonitors.
3300 /// 2) Deserialize the ChannelManager by filling in this struct and calling <(Sha256dHash,
3301 ///    ChannelManager)>::read(reader, args).
3302 ///    This may result in closing some Channels if the ChannelMonitor is newer than the stored
3303 ///    ChannelManager state to ensure no loss of funds. Thus, transactions may be broadcasted.
3304 /// 3) Register all relevant ChannelMonitor outpoints with your chain watch mechanism using
3305 ///    ChannelMonitor::get_monitored_outpoints and ChannelMonitor::get_funding_txo().
3306 /// 4) Reconnect blocks on your ChannelMonitors.
3307 /// 5) Move the ChannelMonitors into your local ManyChannelMonitor.
3308 /// 6) Disconnect/connect blocks on the ChannelManager.
3309 /// 7) Register the new ChannelManager with your ChainWatchInterface.
3310 pub struct ChannelManagerReadArgs<'a, ChanSigner: 'a + ChannelKeys, M: Deref, T: Deref, K: Deref, F: Deref>
3311         where M::Target: ManyChannelMonitor<ChanSigner>,
3312         T::Target: BroadcasterInterface,
3313         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
3314         F::Target: FeeEstimator,
3315 {
3316
3317         /// The keys provider which will give us relevant keys. Some keys will be loaded during
3318         /// deserialization.
3319         pub keys_manager: K,
3320
3321         /// The fee_estimator for use in the ChannelManager in the future.
3322         ///
3323         /// No calls to the FeeEstimator will be made during deserialization.
3324         pub fee_estimator: F,
3325         /// The ManyChannelMonitor for use in the ChannelManager in the future.
3326         ///
3327         /// No calls to the ManyChannelMonitor will be made during deserialization. It is assumed that
3328         /// you have deserialized ChannelMonitors separately and will add them to your
3329         /// ManyChannelMonitor after deserializing this ChannelManager.
3330         pub monitor: M,
3331
3332         /// The BroadcasterInterface which will be used in the ChannelManager in the future and may be
3333         /// used to broadcast the latest local commitment transactions of channels which must be
3334         /// force-closed during deserialization.
3335         pub tx_broadcaster: T,
3336         /// The Logger for use in the ChannelManager and which may be used to log information during
3337         /// deserialization.
3338         pub logger: Arc<Logger>,
3339         /// Default settings used for new channels. Any existing channels will continue to use the
3340         /// runtime settings which were stored when the ChannelManager was serialized.
3341         pub default_config: UserConfig,
3342
3343         /// A map from channel funding outpoints to ChannelMonitors for those channels (ie
3344         /// value.get_funding_txo() should be the key).
3345         ///
3346         /// If a monitor is inconsistent with the channel state during deserialization the channel will
3347         /// be force-closed using the data in the ChannelMonitor and the channel will be dropped. This
3348         /// is true for missing channels as well. If there is a monitor missing for which we find
3349         /// channel data Err(DecodeError::InvalidValue) will be returned.
3350         ///
3351         /// In such cases the latest local transactions will be sent to the tx_broadcaster included in
3352         /// this struct.
3353         pub channel_monitors: &'a mut HashMap<OutPoint, &'a mut ChannelMonitor<ChanSigner>>,
3354 }
3355
3356 // Implement ReadableArgs for an Arc'd ChannelManager to make it a bit easier to work with the
3357 // SipmleArcChannelManager type:
3358 impl<'a, R : ::std::io::Read, ChanSigner: ChannelKeys + Readable<R>, M: Deref, T: Deref, K: Deref, F: Deref>
3359         ReadableArgs<R, ChannelManagerReadArgs<'a, ChanSigner, M, T, K, F>> for (Sha256dHash, Arc<ChannelManager<ChanSigner, M, T, K, F>>)
3360         where M::Target: ManyChannelMonitor<ChanSigner>,
3361         T::Target: BroadcasterInterface,
3362         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
3363         F::Target: FeeEstimator,
3364 {
3365         fn read(reader: &mut R, args: ChannelManagerReadArgs<'a, ChanSigner, M, T, K, F>) -> Result<Self, DecodeError> {
3366                 let (blockhash, chan_manager) = <(Sha256dHash, ChannelManager<ChanSigner, M, T, K, F>)>::read(reader, args)?;
3367                 Ok((blockhash, Arc::new(chan_manager)))
3368         }
3369 }
3370
3371 impl<'a, R : ::std::io::Read, ChanSigner: ChannelKeys + Readable<R>, M: Deref, T: Deref, K: Deref, F: Deref>
3372         ReadableArgs<R, ChannelManagerReadArgs<'a, ChanSigner, M, T, K, F>> for (Sha256dHash, ChannelManager<ChanSigner, M, T, K, F>)
3373         where M::Target: ManyChannelMonitor<ChanSigner>,
3374         T::Target: BroadcasterInterface,
3375         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
3376         F::Target: FeeEstimator,
3377 {
3378         fn read(reader: &mut R, args: ChannelManagerReadArgs<'a, ChanSigner, M, T, K, F>) -> Result<Self, DecodeError> {
3379                 let _ver: u8 = Readable::read(reader)?;
3380                 let min_ver: u8 = Readable::read(reader)?;
3381                 if min_ver > SERIALIZATION_VERSION {
3382                         return Err(DecodeError::UnknownVersion);
3383                 }
3384
3385                 let genesis_hash: Sha256dHash = Readable::read(reader)?;
3386                 let latest_block_height: u32 = Readable::read(reader)?;
3387                 let last_block_hash: Sha256dHash = Readable::read(reader)?;
3388
3389                 let mut closed_channels = Vec::new();
3390
3391                 let channel_count: u64 = Readable::read(reader)?;
3392                 let mut funding_txo_set = HashSet::with_capacity(cmp::min(channel_count as usize, 128));
3393                 let mut by_id = HashMap::with_capacity(cmp::min(channel_count as usize, 128));
3394                 let mut short_to_id = HashMap::with_capacity(cmp::min(channel_count as usize, 128));
3395                 for _ in 0..channel_count {
3396                         let mut channel: Channel<ChanSigner> = ReadableArgs::read(reader, args.logger.clone())?;
3397                         if channel.last_block_connected != Default::default() && channel.last_block_connected != last_block_hash {
3398                                 return Err(DecodeError::InvalidValue);
3399                         }
3400
3401                         let funding_txo = channel.get_funding_txo().ok_or(DecodeError::InvalidValue)?;
3402                         funding_txo_set.insert(funding_txo.clone());
3403                         if let Some(ref mut monitor) = args.channel_monitors.get_mut(&funding_txo) {
3404                                 if channel.get_cur_local_commitment_transaction_number() != monitor.get_cur_local_commitment_number() ||
3405                                                 channel.get_revoked_remote_commitment_transaction_number() != monitor.get_min_seen_secret() ||
3406                                                 channel.get_cur_remote_commitment_transaction_number() != monitor.get_cur_remote_commitment_number() ||
3407                                                 channel.get_latest_monitor_update_id() != monitor.get_latest_update_id() {
3408                                         let mut force_close_res = channel.force_shutdown();
3409                                         force_close_res.0 = monitor.get_latest_local_commitment_txn();
3410                                         closed_channels.push(force_close_res);
3411                                 } else {
3412                                         if let Some(short_channel_id) = channel.get_short_channel_id() {
3413                                                 short_to_id.insert(short_channel_id, channel.channel_id());
3414                                         }
3415                                         by_id.insert(channel.channel_id(), channel);
3416                                 }
3417                         } else {
3418                                 return Err(DecodeError::InvalidValue);
3419                         }
3420                 }
3421
3422                 for (ref funding_txo, ref mut monitor) in args.channel_monitors.iter_mut() {
3423                         if !funding_txo_set.contains(funding_txo) {
3424                                 closed_channels.push((monitor.get_latest_local_commitment_txn(), Vec::new()));
3425                         }
3426                 }
3427
3428                 let forward_htlcs_count: u64 = Readable::read(reader)?;
3429                 let mut forward_htlcs = HashMap::with_capacity(cmp::min(forward_htlcs_count as usize, 128));
3430                 for _ in 0..forward_htlcs_count {
3431                         let short_channel_id = Readable::read(reader)?;
3432                         let pending_forwards_count: u64 = Readable::read(reader)?;
3433                         let mut pending_forwards = Vec::with_capacity(cmp::min(pending_forwards_count as usize, 128));
3434                         for _ in 0..pending_forwards_count {
3435                                 pending_forwards.push(Readable::read(reader)?);
3436                         }
3437                         forward_htlcs.insert(short_channel_id, pending_forwards);
3438                 }
3439
3440                 let claimable_htlcs_count: u64 = Readable::read(reader)?;
3441                 let mut claimable_htlcs = HashMap::with_capacity(cmp::min(claimable_htlcs_count as usize, 128));
3442                 for _ in 0..claimable_htlcs_count {
3443                         let payment_hash = Readable::read(reader)?;
3444                         let previous_hops_len: u64 = Readable::read(reader)?;
3445                         let mut previous_hops = Vec::with_capacity(cmp::min(previous_hops_len as usize, 2));
3446                         for _ in 0..previous_hops_len {
3447                                 previous_hops.push((Readable::read(reader)?, Readable::read(reader)?));
3448                         }
3449                         claimable_htlcs.insert(payment_hash, previous_hops);
3450                 }
3451
3452                 let peer_count: u64 = Readable::read(reader)?;
3453                 let mut per_peer_state = HashMap::with_capacity(cmp::min(peer_count as usize, 128));
3454                 for _ in 0..peer_count {
3455                         let peer_pubkey = Readable::read(reader)?;
3456                         let peer_state = PeerState {
3457                                 latest_features: Readable::read(reader)?,
3458                         };
3459                         per_peer_state.insert(peer_pubkey, Mutex::new(peer_state));
3460                 }
3461
3462                 let channel_manager = ChannelManager {
3463                         genesis_hash,
3464                         fee_estimator: args.fee_estimator,
3465                         monitor: args.monitor,
3466                         tx_broadcaster: args.tx_broadcaster,
3467
3468                         latest_block_height: AtomicUsize::new(latest_block_height as usize),
3469                         last_block_hash: Mutex::new(last_block_hash),
3470                         secp_ctx: Secp256k1::new(),
3471
3472                         channel_state: Mutex::new(ChannelHolder {
3473                                 by_id,
3474                                 short_to_id,
3475                                 forward_htlcs,
3476                                 claimable_htlcs,
3477                                 pending_msg_events: Vec::new(),
3478                         }),
3479                         our_network_key: args.keys_manager.get_node_secret(),
3480
3481                         per_peer_state: RwLock::new(per_peer_state),
3482
3483                         pending_events: Mutex::new(Vec::new()),
3484                         total_consistency_lock: RwLock::new(()),
3485                         keys_manager: args.keys_manager,
3486                         logger: args.logger,
3487                         default_configuration: args.default_config,
3488                 };
3489
3490                 for close_res in closed_channels.drain(..) {
3491                         channel_manager.finish_force_close_channel(close_res);
3492                         //TODO: Broadcast channel update for closed channels, but only after we've made a
3493                         //connection or two.
3494                 }
3495
3496                 Ok((last_block_hash.clone(), channel_manager))
3497         }
3498 }