_ 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 routing::router::get_route 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 use bitcoin::hash_types::BlockHash;
  23
  24 use bitcoin::secp256k1::key::{SecretKey,PublicKey};
  25 use bitcoin::secp256k1::Secp256k1;
  26 use bitcoin::secp256k1::ecdh::SharedSecret;
  27 use bitcoin::secp256k1;
  28
  29 use chain::chaininterface::{BroadcasterInterface,ChainListener,FeeEstimator};
  30 use chain::transaction::OutPoint;
  31 use ln::channel::{Channel, ChannelError};
  32 use ln::channelmonitor::{ChannelMonitor, ChannelMonitorUpdate, ChannelMonitorUpdateErr, ManyChannelMonitor, HTLC_FAIL_BACK_BUFFER, CLTV_CLAIM_BUFFER, LATENCY_GRACE_PERIOD_BLOCKS, ANTI_REORG_DELAY};
  33 use ln::features::{InitFeatures, NodeFeatures};
  34 use routing::router::{Route, RouteHop};
  35 use ln::msgs;
  36 use ln::onion_utils;
  37 use ln::msgs::{ChannelMessageHandler, DecodeError, LightningError, OptionalField};
  38 use chain::keysinterface::{ChannelKeys, KeysInterface, KeysManager, InMemoryChannelKeys};
  39 use util::config::UserConfig;
  40 use util::{byte_utils, events};
  41 use util::ser::{Readable, ReadableArgs, MaybeReadable, Writeable, Writer};
  42 use util::chacha20::{ChaCha20, ChaChaReader};
  43 use util::logger::Logger;
  44 use util::errors::APIError;
  45
  46 use std::{cmp, mem};
  47 use std::collections::{HashMap, hash_map, HashSet};
  48 use std::io::{Cursor, Read};
  49 use std::sync::{Arc, Mutex, MutexGuard, RwLock};
  50 use std::sync::atomic::{AtomicUsize, Ordering};
  51 use std::time::Duration;
  52 use std::marker::{Sync, Send};
  53 use std::ops::Deref;
  54 use bitcoin::hashes::hex::ToHex;
  55
  56 // We hold various information about HTLC relay in the HTLC objects in Channel itself:
  57 //
  58 // Upon receipt of an HTLC from a peer, we'll give it a PendingHTLCStatus indicating if it should
  59 // forward the HTLC with information it will give back to us when it does so, or if it should Fail
  60 // the HTLC with the relevant message for the Channel to handle giving to the remote peer.
  61 //
  62 // Once said HTLC is committed in the Channel, if the PendingHTLCStatus indicated Forward, the
  63 // Channel will return the PendingHTLCInfo back to us, and we will create an HTLCForwardInfo
  64 // with it to track where it came from (in case of onwards-forward error), waiting a random delay
  65 // before we forward it.
  66 //
  67 // We will then use HTLCForwardInfo's PendingHTLCInfo to construct an outbound HTLC, with a
  68 // relevant HTLCSource::PreviousHopData filled in to indicate where it came from (which we can use
  69 // to either fail-backwards or fulfill the HTLC backwards along the relevant path).
  70 // Alternatively, we can fill an outbound HTLC with a HTLCSource::OutboundRoute indicating this is
  71 // our payment, which we can use to decode errors or inform the user that the payment was sent.
  72
  73 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
  74 enum PendingHTLCRouting {
  75         Forward {
  76                 onion_packet: msgs::OnionPacket,
  77                 short_channel_id: u64, // This should be NonZero<u64> eventually when we bump MSRV
  78         },
  79         Receive {
  80                 payment_data: Option<msgs::FinalOnionHopData>,
  81                 incoming_cltv_expiry: u32, // Used to track when we should expire pending HTLCs that go unclaimed
  82         },
  83 }
  84
  85 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
  86 pub(super) struct PendingHTLCInfo {
  87         routing: PendingHTLCRouting,
  88         incoming_shared_secret: [u8; 32],
  89         payment_hash: PaymentHash,
  90         pub(super) amt_to_forward: u64,
  91         pub(super) outgoing_cltv_value: u32,
  92 }
  93
  94 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
  95 pub(super) enum HTLCFailureMsg {
  96         Relay(msgs::UpdateFailHTLC),
  97         Malformed(msgs::UpdateFailMalformedHTLC),
  98 }
  99
 100 /// Stores whether we can't forward an HTLC or relevant forwarding info
 101 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
 102 pub(super) enum PendingHTLCStatus {
 103         Forward(PendingHTLCInfo),
 104         Fail(HTLCFailureMsg),
 105 }
 106
 107 pub(super) enum HTLCForwardInfo {
 108         AddHTLC {
 109                 prev_short_channel_id: u64,
 110                 prev_htlc_id: u64,
 111                 forward_info: PendingHTLCInfo,
 112         },
 113         FailHTLC {
 114                 htlc_id: u64,
 115                 err_packet: msgs::OnionErrorPacket,
 116         },
 117 }
 118
 119 /// Tracks the inbound corresponding to an outbound HTLC
 120 #[derive(Clone, PartialEq)]
 121 pub(super) struct HTLCPreviousHopData {
 122         short_channel_id: u64,
 123         htlc_id: u64,
 124         incoming_packet_shared_secret: [u8; 32],
 125 }
 126
 127 struct ClaimableHTLC {
 128         prev_hop: HTLCPreviousHopData,
 129         value: u64,
 130         /// Filled in when the HTLC was received with a payment_secret packet, which contains a
 131         /// total_msat (which may differ from value if this is a Multi-Path Payment) and a
 132         /// payment_secret which prevents path-probing attacks and can associate different HTLCs which
 133         /// are part of the same payment.
 134         payment_data: Option<msgs::FinalOnionHopData>,
 135         cltv_expiry: u32,
 136 }
 137
 138 /// Tracks the inbound corresponding to an outbound HTLC
 139 #[derive(Clone, PartialEq)]
 140 pub(super) enum HTLCSource {
 141         PreviousHopData(HTLCPreviousHopData),
 142         OutboundRoute {
 143                 path: Vec<RouteHop>,
 144                 session_priv: SecretKey,
 145                 /// Technically we can recalculate this from the route, but we cache it here to avoid
 146                 /// doing a double-pass on route when we get a failure back
 147                 first_hop_htlc_msat: u64,
 148         },
 149 }
 150 #[cfg(test)]
 151 impl HTLCSource {
 152         pub fn dummy() -> Self {
 153                 HTLCSource::OutboundRoute {
 154                         path: Vec::new(),
 155                         session_priv: SecretKey::from_slice(&[1; 32]).unwrap(),
 156                         first_hop_htlc_msat: 0,
 157                 }
 158         }
 159 }
 160
 161 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
 162 pub(super) enum HTLCFailReason {
 163         LightningError {
 164                 err: msgs::OnionErrorPacket,
 165         },
 166         Reason {
 167                 failure_code: u16,
 168                 data: Vec<u8>,
 169         }
 170 }
 171
 172 /// payment_hash type, use to cross-lock hop
 173 #[derive(Hash, Copy, Clone, PartialEq, Eq, Debug)]
 174 pub struct PaymentHash(pub [u8;32]);
 175 /// payment_preimage type, use to route payment between hop
 176 #[derive(Hash, Copy, Clone, PartialEq, Eq, Debug)]
 177 pub struct PaymentPreimage(pub [u8;32]);
 178 /// payment_secret type, use to authenticate sender to the receiver and tie MPP HTLCs together
 179 #[derive(Hash, Copy, Clone, PartialEq, Eq, Debug)]
 180 pub struct PaymentSecret(pub [u8;32]);
 181
 182 type ShutdownResult = (Option<OutPoint>, ChannelMonitorUpdate, Vec<(HTLCSource, PaymentHash)>);
 183
 184 /// Error type returned across the channel_state mutex boundary. When an Err is generated for a
 185 /// Channel, we generally end up with a ChannelError::Close for which we have to close the channel
 186 /// immediately (ie with no further calls on it made). Thus, this step happens inside a
 187 /// channel_state lock. We then return the set of things that need to be done outside the lock in
 188 /// this struct and call handle_error!() on it.
 189
 190 struct MsgHandleErrInternal {
 191         err: msgs::LightningError,
 192         shutdown_finish: Option<(ShutdownResult, Option<msgs::ChannelUpdate>)>,
 193 }
 194 impl MsgHandleErrInternal {
 195         #[inline]
 196         fn send_err_msg_no_close(err: String, channel_id: [u8; 32]) -> Self {
 197                 Self {
 198                         err: LightningError {
 199                                 err: err.clone(),
 200                                 action: msgs::ErrorAction::SendErrorMessage {
 201                                         msg: msgs::ErrorMessage {
 202                                                 channel_id,
 203                                                 data: err
 204                                         },
 205                                 },
 206                         },
 207                         shutdown_finish: None,
 208                 }
 209         }
 210         #[inline]
 211         fn ignore_no_close(err: String) -> Self {
 212                 Self {
 213                         err: LightningError {
 214                                 err,
 215                                 action: msgs::ErrorAction::IgnoreError,
 216                         },
 217                         shutdown_finish: None,
 218                 }
 219         }
 220         #[inline]
 221         fn from_no_close(err: msgs::LightningError) -> Self {
 222                 Self { err, shutdown_finish: None }
 223         }
 224         #[inline]
 225         fn from_finish_shutdown(err: String, channel_id: [u8; 32], shutdown_res: ShutdownResult, channel_update: Option<msgs::ChannelUpdate>) -> Self {
 226                 Self {
 227                         err: LightningError {
 228                                 err: err.clone(),
 229                                 action: msgs::ErrorAction::SendErrorMessage {
 230                                         msg: msgs::ErrorMessage {
 231                                                 channel_id,
 232                                                 data: err
 233                                         },
 234                                 },
 235                         },
 236                         shutdown_finish: Some((shutdown_res, channel_update)),
 237                 }
 238         }
 239         #[inline]
 240         fn from_chan_no_close(err: ChannelError, channel_id: [u8; 32]) -> Self {
 241                 Self {
 242                         err: match err {
 243                                 ChannelError::Ignore(msg) => LightningError {
 244                                         err: msg,
 245                                         action: msgs::ErrorAction::IgnoreError,
 246                                 },
 247                                 ChannelError::Close(msg) => LightningError {
 248                                         err: msg.clone(),
 249                                         action: msgs::ErrorAction::SendErrorMessage {
 250                                                 msg: msgs::ErrorMessage {
 251                                                         channel_id,
 252                                                         data: msg
 253                                                 },
 254                                         },
 255                                 },
 256                                 ChannelError::CloseDelayBroadcast(msg) => LightningError {
 257                                         err: msg.clone(),
 258                                         action: msgs::ErrorAction::SendErrorMessage {
 259                                                 msg: msgs::ErrorMessage {
 260                                                         channel_id,
 261                                                         data: msg
 262                                                 },
 263                                         },
 264                                 },
 265                         },
 266                         shutdown_finish: None,
 267                 }
 268         }
 269 }
 270
 271 /// We hold back HTLCs we intend to relay for a random interval greater than this (see
 272 /// Event::PendingHTLCsForwardable for the API guidelines indicating how long should be waited).
 273 /// This provides some limited amount of privacy. Ideally this would range from somewhere like one
 274 /// second to 30 seconds, but people expect lightning to be, you know, kinda fast, sadly.
 275 const MIN_HTLC_RELAY_HOLDING_CELL_MILLIS: u64 = 100;
 276
 277 /// For events which result in both a RevokeAndACK and a CommitmentUpdate, by default they should
 278 /// be sent in the order they appear in the return value, however sometimes the order needs to be
 279 /// variable at runtime (eg Channel::channel_reestablish needs to re-send messages in the order
 280 /// they were originally sent). In those cases, this enum is also returned.
 281 #[derive(Clone, PartialEq)]
 282 pub(super) enum RAACommitmentOrder {
 283         /// Send the CommitmentUpdate messages first
 284         CommitmentFirst,
 285         /// Send the RevokeAndACK message first
 286         RevokeAndACKFirst,
 287 }
 288
 289 // Note this is only exposed in cfg(test):
 290 pub(super) struct ChannelHolder<ChanSigner: ChannelKeys> {
 291         pub(super) by_id: HashMap<[u8; 32], Channel<ChanSigner>>,
 292         pub(super) short_to_id: HashMap<u64, [u8; 32]>,
 293         /// short channel id -> forward infos. Key of 0 means payments received
 294         /// Note that while this is held in the same mutex as the channels themselves, no consistency
 295         /// guarantees are made about the existence of a channel with the short id here, nor the short
 296         /// ids in the PendingHTLCInfo!
 297         pub(super) forward_htlcs: HashMap<u64, Vec<HTLCForwardInfo>>,
 298         /// (payment_hash, payment_secret) -> Vec<HTLCs> for tracking HTLCs that
 299         /// were to us and can be failed/claimed by the user
 300         /// Note that while this is held in the same mutex as the channels themselves, no consistency
 301         /// guarantees are made about the channels given here actually existing anymore by the time you
 302         /// go to read them!
 303         claimable_htlcs: HashMap<(PaymentHash, Option<PaymentSecret>), Vec<ClaimableHTLC>>,
 304         /// Messages to send to peers - pushed to in the same lock that they are generated in (except
 305         /// for broadcast messages, where ordering isn't as strict).
 306         pub(super) pending_msg_events: Vec<events::MessageSendEvent>,
 307 }
 308
 309 /// State we hold per-peer. In the future we should put channels in here, but for now we only hold
 310 /// the latest Init features we heard from the peer.
 311 struct PeerState {
 312         latest_features: InitFeatures,
 313 }
 314
 315 #[cfg(not(any(target_pointer_width = "32", target_pointer_width = "64")))]
 316 const ERR: () = "You need at least 32 bit pointers (well, usize, but we'll assume they're the same) for ChannelManager::latest_block_height";
 317
 318 /// SimpleArcChannelManager is useful when you need a ChannelManager with a static lifetime, e.g.
 319 /// when you're using lightning-net-tokio (since tokio::spawn requires parameters with static
 320 /// lifetimes). Other times you can afford a reference, which is more efficient, in which case
 321 /// SimpleRefChannelManager is the more appropriate type. Defining these type aliases prevents
 322 /// issues such as overly long function definitions. Note that the ChannelManager can take any
 323 /// type that implements KeysInterface for its keys manager, but this type alias chooses the
 324 /// concrete type of the KeysManager.
 325 pub type SimpleArcChannelManager<M, T, F, L> = Arc<ChannelManager<InMemoryChannelKeys, Arc<M>, Arc<T>, Arc<KeysManager>, Arc<F>, Arc<L>>>;
 326
 327 /// SimpleRefChannelManager is a type alias for a ChannelManager reference, and is the reference
 328 /// counterpart to the SimpleArcChannelManager type alias. Use this type by default when you don't
 329 /// need a ChannelManager with a static lifetime. You'll need a static lifetime in cases such as
 330 /// usage of lightning-net-tokio (since tokio::spawn requires parameters with static lifetimes).
 331 /// But if this is not necessary, using a reference is more efficient. Defining these type aliases
 332 /// helps with issues such as long function definitions. Note that the ChannelManager can take any
 333 /// type that implements KeysInterface for its keys manager, but this type alias chooses the
 334 /// concrete type of the KeysManager.
 335 pub type SimpleRefChannelManager<'a, 'b, 'c, 'd, 'e, M, T, F, L> = ChannelManager<InMemoryChannelKeys, &'a M, &'b T, &'c KeysManager, &'d F, &'e L>;
 336
 337 /// Manager which keeps track of a number of channels and sends messages to the appropriate
 338 /// channel, also tracking HTLC preimages and forwarding onion packets appropriately.
 339 ///
 340 /// Implements ChannelMessageHandler, handling the multi-channel parts and passing things through
 341 /// to individual Channels.
 342 ///
 343 /// Implements Writeable to write out all channel state to disk. Implies peer_disconnected() for
 344 /// all peers during write/read (though does not modify this instance, only the instance being
 345 /// serialized). This will result in any channels which have not yet exchanged funding_created (ie
 346 /// called funding_transaction_generated for outbound channels).
 347 ///
 348 /// Note that you can be a bit lazier about writing out ChannelManager than you can be with
 349 /// ChannelMonitors. With ChannelMonitors you MUST write each monitor update out to disk before
 350 /// returning from ManyChannelMonitor::add_/update_monitor, with ChannelManagers, writing updates
 351 /// happens out-of-band (and will prevent any other ChannelManager operations from occurring during
 352 /// the serialization process). If the deserialized version is out-of-date compared to the
 353 /// ChannelMonitors passed by reference to read(), those channels will be force-closed based on the
 354 /// ChannelMonitor state and no funds will be lost (mod on-chain transaction fees).
 355 ///
 356 /// Note that the deserializer is only implemented for (Sha256dHash, ChannelManager), which
 357 /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
 358 /// the "reorg path" (ie call block_disconnected() until you get to a common block and then call
 359 /// block_connected() to step towards your best block) upon deserialization before using the
 360 /// object!
 361 ///
 362 /// Note that ChannelManager is responsible for tracking liveness of its channels and generating
 363 /// ChannelUpdate messages informing peers that the channel is temporarily disabled. To avoid
 364 /// spam due to quick disconnection/reconnection, updates are not sent until the channel has been
 365 /// offline for a full minute. In order to track this, you must call
 366 /// timer_chan_freshness_every_min roughly once per minute, though it doesn't have to be perfect.
 367 ///
 368 /// Rather than using a plain ChannelManager, it is preferable to use either a SimpleArcChannelManager
 369 /// a SimpleRefChannelManager, for conciseness. See their documentation for more details, but
 370 /// essentially you should default to using a SimpleRefChannelManager, and use a
 371 /// SimpleArcChannelManager when you require a ChannelManager with a static lifetime, such as when
 372 /// you're using lightning-net-tokio.
 373 pub struct ChannelManager<ChanSigner: ChannelKeys, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
 374         where M::Target: ManyChannelMonitor<Keys=ChanSigner>,
 375         T::Target: BroadcasterInterface,
 376         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
 377         F::Target: FeeEstimator,
 378                                 L::Target: Logger,
 379 {
 380         default_configuration: UserConfig,
 381         genesis_hash: BlockHash,
 382         fee_estimator: F,
 383         monitor: M,
 384         tx_broadcaster: T,
 385
 386         #[cfg(test)]
 387         pub(super) latest_block_height: AtomicUsize,
 388         #[cfg(not(test))]
 389         latest_block_height: AtomicUsize,
 390         last_block_hash: Mutex<BlockHash>,
 391         secp_ctx: Secp256k1<secp256k1::All>,
 392
 393         #[cfg(test)]
 394         pub(super) channel_state: Mutex<ChannelHolder<ChanSigner>>,
 395         #[cfg(not(test))]
 396         channel_state: Mutex<ChannelHolder<ChanSigner>>,
 397         our_network_key: SecretKey,
 398
 399         /// Used to track the last value sent in a node_announcement "timestamp" field. We ensure this
 400         /// value increases strictly since we don't assume access to a time source.
 401         last_node_announcement_serial: AtomicUsize,
 402
 403         /// The bulk of our storage will eventually be here (channels and message queues and the like).
 404         /// If we are connected to a peer we always at least have an entry here, even if no channels
 405         /// are currently open with that peer.
 406         /// Because adding or removing an entry is rare, we usually take an outer read lock and then
 407         /// operate on the inner value freely. Sadly, this prevents parallel operation when opening a
 408         /// new channel.
 409         per_peer_state: RwLock<HashMap<PublicKey, Mutex<PeerState>>>,
 410
 411         pending_events: Mutex<Vec<events::Event>>,
 412         /// Used when we have to take a BIG lock to make sure everything is self-consistent.
 413         /// Essentially just when we're serializing ourselves out.
 414         /// Taken first everywhere where we are making changes before any other locks.
 415         total_consistency_lock: RwLock<()>,
 416
 417         keys_manager: K,
 418
 419         logger: L,
 420 }
 421
 422 /// The amount of time we require our counterparty wait to claim their money (ie time between when
 423 /// we, or our watchtower, must check for them having broadcast a theft transaction).
 424 pub(crate) const BREAKDOWN_TIMEOUT: u16 = 6 * 24;
 425 /// The amount of time we're willing to wait to claim money back to us
 426 pub(crate) const MAX_LOCAL_BREAKDOWN_TIMEOUT: u16 = 6 * 24 * 7;
 427
 428 /// The minimum number of blocks between an inbound HTLC's CLTV and the corresponding outbound
 429 /// HTLC's CLTV. This should always be a few blocks greater than channelmonitor::CLTV_CLAIM_BUFFER,
 430 /// ie the node we forwarded the payment on to should always have enough room to reliably time out
 431 /// the HTLC via a full update_fail_htlc/commitment_signed dance before we hit the
 432 /// CLTV_CLAIM_BUFFER point (we static assert that it's at least 3 blocks more).
 433 const CLTV_EXPIRY_DELTA: u16 = 6 * 12; //TODO?
 434 pub(super) const CLTV_FAR_FAR_AWAY: u32 = 6 * 24 * 7; //TODO?
 435
 436 // Check that our CLTV_EXPIRY is at least CLTV_CLAIM_BUFFER + ANTI_REORG_DELAY + LATENCY_GRACE_PERIOD_BLOCKS,
 437 // ie that if the next-hop peer fails the HTLC within
 438 // LATENCY_GRACE_PERIOD_BLOCKS then we'll still have CLTV_CLAIM_BUFFER left to timeout it onchain,
 439 // then waiting ANTI_REORG_DELAY to be reorg-safe on the outbound HLTC and
 440 // failing the corresponding htlc backward, and us now seeing the last block of ANTI_REORG_DELAY before
 441 // LATENCY_GRACE_PERIOD_BLOCKS.
 442 #[deny(const_err)]
 443 #[allow(dead_code)]
 444 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;
 445
 446 // Check for ability of an attacker to make us fail on-chain by delaying inbound claim. See
 447 // ChannelMontior::would_broadcast_at_height for a description of why this is needed.
 448 #[deny(const_err)]
 449 #[allow(dead_code)]
 450 const CHECK_CLTV_EXPIRY_SANITY_2: u32 = CLTV_EXPIRY_DELTA as u32 - LATENCY_GRACE_PERIOD_BLOCKS - 2*CLTV_CLAIM_BUFFER;
 451
 452 /// Details of a channel, as returned by ChannelManager::list_channels and ChannelManager::list_usable_channels
 453 pub struct ChannelDetails {
 454         /// The channel's ID (prior to funding transaction generation, this is a random 32 bytes,
 455         /// thereafter this is the txid of the funding transaction xor the funding transaction output).
 456         /// Note that this means this value is *not* persistent - it can change once during the
 457         /// lifetime of the channel.
 458         pub channel_id: [u8; 32],
 459         /// The position of the funding transaction in the chain. None if the funding transaction has
 460         /// not yet been confirmed and the channel fully opened.
 461         pub short_channel_id: Option<u64>,
 462         /// The node_id of our counterparty
 463         pub remote_network_id: PublicKey,
 464         /// The Features the channel counterparty provided upon last connection.
 465         /// Useful for routing as it is the most up-to-date copy of the counterparty's features and
 466         /// many routing-relevant features are present in the init context.
 467         pub counterparty_features: InitFeatures,
 468         /// The value, in satoshis, of this channel as appears in the funding output
 469         pub channel_value_satoshis: u64,
 470         /// The user_id passed in to create_channel, or 0 if the channel was inbound.
 471         pub user_id: u64,
 472         /// The available outbound capacity for sending HTLCs to the remote peer. This does not include
 473         /// any pending HTLCs which are not yet fully resolved (and, thus, who's balance is not
 474         /// available for inclusion in new outbound HTLCs). This further does not include any pending
 475         /// outgoing HTLCs which are awaiting some other resolution to be sent.
 476         pub outbound_capacity_msat: u64,
 477         /// The available inbound capacity for the remote peer to send HTLCs to us. This does not
 478         /// include any pending HTLCs which are not yet fully resolved (and, thus, who's balance is not
 479         /// available for inclusion in new inbound HTLCs).
 480         /// Note that there are some corner cases not fully handled here, so the actual available
 481         /// inbound capacity may be slightly higher than this.
 482         pub inbound_capacity_msat: u64,
 483         /// True if the channel is (a) confirmed and funding_locked messages have been exchanged, (b)
 484         /// the peer is connected, and (c) no monitor update failure is pending resolution.
 485         pub is_live: bool,
 486 }
 487
 488 /// If a payment fails to send, it can be in one of several states. This enum is returned as the
 489 /// Err() type describing which state the payment is in, see the description of individual enum
 490 /// states for more.
 491 #[derive(Debug)]
 492 pub enum PaymentSendFailure {
 493         /// A parameter which was passed to send_payment was invalid, preventing us from attempting to
 494         /// send the payment at all. No channel state has been changed or messages sent to peers, and
 495         /// once you've changed the parameter at error, you can freely retry the payment in full.
 496         ParameterError(APIError),
 497         /// A parameter in a single path which was passed to send_payment was invalid, preventing us
 498         /// from attempting to send the payment at all. No channel state has been changed or messages
 499         /// sent to peers, and once you've changed the parameter at error, you can freely retry the
 500         /// payment in full.
 501         ///
 502         /// The results here are ordered the same as the paths in the route object which was passed to
 503         /// send_payment.
 504         PathParameterError(Vec<Result<(), APIError>>),
 505         /// All paths which were attempted failed to send, with no channel state change taking place.
 506         /// You can freely retry the payment in full (though you probably want to do so over different
 507         /// paths than the ones selected).
 508         AllFailedRetrySafe(Vec<APIError>),
 509         /// Some paths which were attempted failed to send, though possibly not all. At least some
 510         /// paths have irrevocably committed to the HTLC and retrying the payment in full would result
 511         /// in over-/re-payment.
 512         ///
 513         /// The results here are ordered the same as the paths in the route object which was passed to
 514         /// send_payment, and any Errs which are not APIError::MonitorUpdateFailed can be safely
 515         /// retried (though there is currently no API with which to do so).
 516         ///
 517         /// Any entries which contain Err(APIError::MonitorUpdateFailed) or Ok(()) MUST NOT be retried
 518         /// as they will result in over-/re-payment. These HTLCs all either successfully sent (in the
 519         /// case of Ok(())) or will send once channel_monitor_updated is called on the next-hop channel
 520         /// with the latest update_id.
 521         PartialFailure(Vec<Result<(), APIError>>),
 522 }
 523
 524 macro_rules! handle_error {
 525         ($self: ident, $internal: expr, $their_node_id: expr) => {
 526                 match $internal {
 527                         Ok(msg) => Ok(msg),
 528                         Err(MsgHandleErrInternal { err, shutdown_finish }) => {
 529                                 #[cfg(debug_assertions)]
 530                                 {
 531                                         // In testing, ensure there are no deadlocks where the lock is already held upon
 532                                         // entering the macro.
 533                                         assert!($self.channel_state.try_lock().is_ok());
 534                                 }
 535
 536                                 let mut msg_events = Vec::with_capacity(2);
 537
 538                                 if let Some((shutdown_res, update_option)) = shutdown_finish {
 539                                         $self.finish_force_close_channel(shutdown_res);
 540                                         if let Some(update) = update_option {
 541                                                 msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
 542                                                         msg: update
 543                                                 });
 544                                         }
 545                                 }
 546
 547                                 log_error!($self.logger, "{}", err.err);
 548                                 if let msgs::ErrorAction::IgnoreError = err.action {
 549                                 } else {
 550                                         msg_events.push(events::MessageSendEvent::HandleError {
 551                                                 node_id: $their_node_id,
 552                                                 action: err.action.clone()
 553                                         });
 554                                 }
 555
 556                                 if !msg_events.is_empty() {
 557                                         $self.channel_state.lock().unwrap().pending_msg_events.append(&mut msg_events);
 558                                 }
 559
 560                                 // Return error in case higher-API need one
 561                                 Err(err)
 562                         },
 563                 }
 564         }
 565 }
 566
 567 macro_rules! break_chan_entry {
 568         ($self: ident, $res: expr, $channel_state: expr, $entry: expr) => {
 569                 match $res {
 570                         Ok(res) => res,
 571                         Err(ChannelError::Ignore(msg)) => {
 572                                 break Err(MsgHandleErrInternal::from_chan_no_close(ChannelError::Ignore(msg), $entry.key().clone()))
 573                         },
 574                         Err(ChannelError::Close(msg)) => {
 575                                 log_trace!($self.logger, "Closing channel {} due to Close-required error: {}", log_bytes!($entry.key()[..]), msg);
 576                                 let (channel_id, mut chan) = $entry.remove_entry();
 577                                 if let Some(short_id) = chan.get_short_channel_id() {
 578                                         $channel_state.short_to_id.remove(&short_id);
 579                                 }
 580                                 break Err(MsgHandleErrInternal::from_finish_shutdown(msg, channel_id, chan.force_shutdown(true), $self.get_channel_update(&chan).ok()))
 581                         },
 582                         Err(ChannelError::CloseDelayBroadcast(_)) => { panic!("Wait is only generated on receipt of channel_reestablish, which is handled by try_chan_entry, we don't bother to support it here"); }
 583                 }
 584         }
 585 }
 586
 587 macro_rules! try_chan_entry {
 588         ($self: ident, $res: expr, $channel_state: expr, $entry: expr) => {
 589                 match $res {
 590                         Ok(res) => res,
 591                         Err(ChannelError::Ignore(msg)) => {
 592                                 return Err(MsgHandleErrInternal::from_chan_no_close(ChannelError::Ignore(msg), $entry.key().clone()))
 593                         },
 594                         Err(ChannelError::Close(msg)) => {
 595                                 log_trace!($self.logger, "Closing channel {} due to Close-required error: {}", log_bytes!($entry.key()[..]), msg);
 596                                 let (channel_id, mut chan) = $entry.remove_entry();
 597                                 if let Some(short_id) = chan.get_short_channel_id() {
 598                                         $channel_state.short_to_id.remove(&short_id);
 599                                 }
 600                                 return Err(MsgHandleErrInternal::from_finish_shutdown(msg, channel_id, chan.force_shutdown(true), $self.get_channel_update(&chan).ok()))
 601                         },
 602                         Err(ChannelError::CloseDelayBroadcast(msg)) => {
 603                                 log_error!($self.logger, "Channel {} need to be shutdown but closing transactions not broadcast due to {}", log_bytes!($entry.key()[..]), msg);
 604                                 let (channel_id, mut chan) = $entry.remove_entry();
 605                                 if let Some(short_id) = chan.get_short_channel_id() {
 606                                         $channel_state.short_to_id.remove(&short_id);
 607                                 }
 608                                 let shutdown_res = chan.force_shutdown(false);
 609                                 return Err(MsgHandleErrInternal::from_finish_shutdown(msg, channel_id, shutdown_res, $self.get_channel_update(&chan).ok()))
 610                         }
 611                 }
 612         }
 613 }
 614
 615 macro_rules! handle_monitor_err {
 616         ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $resend_raa: expr, $resend_commitment: expr) => {
 617                 handle_monitor_err!($self, $err, $channel_state, $entry, $action_type, $resend_raa, $resend_commitment, Vec::new(), Vec::new())
 618         };
 619         ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $resend_raa: expr, $resend_commitment: expr, $failed_forwards: expr, $failed_fails: expr) => {
 620                 match $err {
 621                         ChannelMonitorUpdateErr::PermanentFailure => {
 622                                 log_error!($self.logger, "Closing channel {} due to monitor update PermanentFailure", log_bytes!($entry.key()[..]));
 623                                 let (channel_id, mut chan) = $entry.remove_entry();
 624                                 if let Some(short_id) = chan.get_short_channel_id() {
 625                                         $channel_state.short_to_id.remove(&short_id);
 626                                 }
 627                                 // TODO: $failed_fails is dropped here, which will cause other channels to hit the
 628                                 // chain in a confused state! We need to move them into the ChannelMonitor which
 629                                 // will be responsible for failing backwards once things confirm on-chain.
 630                                 // It's ok that we drop $failed_forwards here - at this point we'd rather they
 631                                 // broadcast HTLC-Timeout and pay the associated fees to get their funds back than
 632                                 // us bother trying to claim it just to forward on to another peer. If we're
 633                                 // splitting hairs we'd prefer to claim payments that were to us, but we haven't
 634                                 // given up the preimage yet, so might as well just wait until the payment is
 635                                 // retried, avoiding the on-chain fees.
 636                                 let res: Result<(), _> = Err(MsgHandleErrInternal::from_finish_shutdown("ChannelMonitor storage failure".to_owned(), channel_id, chan.force_shutdown(true), $self.get_channel_update(&chan).ok()));
 637                                 res
 638                         },
 639                         ChannelMonitorUpdateErr::TemporaryFailure => {
 640                                 log_info!($self.logger, "Disabling channel {} due to monitor update TemporaryFailure. On restore will send {} and process {} forwards and {} fails",
 641                                                 log_bytes!($entry.key()[..]),
 642                                                 if $resend_commitment && $resend_raa {
 643                                                                 match $action_type {
 644                                                                         RAACommitmentOrder::CommitmentFirst => { "commitment then RAA" },
 645                                                                         RAACommitmentOrder::RevokeAndACKFirst => { "RAA then commitment" },
 646                                                                 }
 647                                                         } else if $resend_commitment { "commitment" }
 648                                                         else if $resend_raa { "RAA" }
 649                                                         else { "nothing" },
 650                                                 (&$failed_forwards as &Vec<(PendingHTLCInfo, u64)>).len(),
 651                                                 (&$failed_fails as &Vec<(HTLCSource, PaymentHash, HTLCFailReason)>).len());
 652                                 if !$resend_commitment {
 653                                         debug_assert!($action_type == RAACommitmentOrder::RevokeAndACKFirst || !$resend_raa);
 654                                 }
 655                                 if !$resend_raa {
 656                                         debug_assert!($action_type == RAACommitmentOrder::CommitmentFirst || !$resend_commitment);
 657                                 }
 658                                 $entry.get_mut().monitor_update_failed($resend_raa, $resend_commitment, $failed_forwards, $failed_fails);
 659                                 Err(MsgHandleErrInternal::from_chan_no_close(ChannelError::Ignore("Failed to update ChannelMonitor".to_owned()), *$entry.key()))
 660                         },
 661                 }
 662         }
 663 }
 664
 665 macro_rules! return_monitor_err {
 666         ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $resend_raa: expr, $resend_commitment: expr) => {
 667                 return handle_monitor_err!($self, $err, $channel_state, $entry, $action_type, $resend_raa, $resend_commitment);
 668         };
 669         ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $resend_raa: expr, $resend_commitment: expr, $failed_forwards: expr, $failed_fails: expr) => {
 670                 return handle_monitor_err!($self, $err, $channel_state, $entry, $action_type, $resend_raa, $resend_commitment, $failed_forwards, $failed_fails);
 671         }
 672 }
 673
 674 // Does not break in case of TemporaryFailure!
 675 macro_rules! maybe_break_monitor_err {
 676         ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $resend_raa: expr, $resend_commitment: expr) => {
 677                 match (handle_monitor_err!($self, $err, $channel_state, $entry, $action_type, $resend_raa, $resend_commitment), $err) {
 678                         (e, ChannelMonitorUpdateErr::PermanentFailure) => {
 679                                 break e;
 680                         },
 681                         (_, ChannelMonitorUpdateErr::TemporaryFailure) => { },
 682                 }
 683         }
 684 }
 685
 686 impl<ChanSigner: ChannelKeys, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelManager<ChanSigner, M, T, K, F, L>
 687         where M::Target: ManyChannelMonitor<Keys=ChanSigner>,
 688         T::Target: BroadcasterInterface,
 689         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
 690         F::Target: FeeEstimator,
 691         L::Target: Logger,
 692 {
 693         /// Constructs a new ChannelManager to hold several channels and route between them.
 694         ///
 695         /// This is the main "logic hub" for all channel-related actions, and implements
 696         /// ChannelMessageHandler.
 697         ///
 698         /// Non-proportional fees are fixed according to our risk using the provided fee estimator.
 699         ///
 700         /// panics if channel_value_satoshis is >= `MAX_FUNDING_SATOSHIS`!
 701         ///
 702         /// Users must provide the current blockchain height from which to track onchain channel
 703         /// funding outpoints and send payments with reliable timelocks.
 704         ///
 705         /// Users need to notify the new ChannelManager when a new block is connected or
 706         /// disconnected using its `block_connected` and `block_disconnected` methods.
 707         /// However, rather than calling these methods directly, the user should register
 708         /// the ChannelManager as a listener to the BlockNotifier and call the BlockNotifier's
 709         /// `block_(dis)connected` methods, which will notify all registered listeners in one
 710         /// go.
 711         pub fn new(network: Network, fee_est: F, monitor: M, tx_broadcaster: T, logger: L, keys_manager: K, config: UserConfig, current_blockchain_height: usize) -> Self {
 712                 let secp_ctx = Secp256k1::new();
 713
 714                 ChannelManager {
 715                         default_configuration: config.clone(),
 716                         genesis_hash: genesis_block(network).header.bitcoin_hash(),
 717                         fee_estimator: fee_est,
 718                         monitor,
 719                         tx_broadcaster,
 720
 721                         latest_block_height: AtomicUsize::new(current_blockchain_height),
 722                         last_block_hash: Mutex::new(Default::default()),
 723                         secp_ctx,
 724
 725                         channel_state: Mutex::new(ChannelHolder{
 726                                 by_id: HashMap::new(),
 727                                 short_to_id: HashMap::new(),
 728                                 forward_htlcs: HashMap::new(),
 729                                 claimable_htlcs: HashMap::new(),
 730                                 pending_msg_events: Vec::new(),
 731                         }),
 732                         our_network_key: keys_manager.get_node_secret(),
 733
 734                         last_node_announcement_serial: AtomicUsize::new(0),
 735
 736                         per_peer_state: RwLock::new(HashMap::new()),
 737
 738                         pending_events: Mutex::new(Vec::new()),
 739                         total_consistency_lock: RwLock::new(()),
 740
 741                         keys_manager,
 742
 743                         logger,
 744                 }
 745         }
 746
 747         /// Creates a new outbound channel to the given remote node and with the given value.
 748         ///
 749         /// user_id will be provided back as user_channel_id in FundingGenerationReady and
 750         /// FundingBroadcastSafe events to allow tracking of which events correspond with which
 751         /// create_channel call. Note that user_channel_id defaults to 0 for inbound channels, so you
 752         /// may wish to avoid using 0 for user_id here.
 753         ///
 754         /// If successful, will generate a SendOpenChannel message event, so you should probably poll
 755         /// PeerManager::process_events afterwards.
 756         ///
 757         /// Raises APIError::APIMisuseError when channel_value_satoshis > 2**24 or push_msat is
 758         /// greater than channel_value_satoshis * 1k or channel_value_satoshis is < 1000.
 759         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> {
 760                 if channel_value_satoshis < 1000 {
 761                         return Err(APIError::APIMisuseError { err: format!("Channel value must be at least 1000 satoshis. It was {}", channel_value_satoshis) });
 762                 }
 763
 764                 let config = if override_config.is_some() { override_config.as_ref().unwrap() } else { &self.default_configuration };
 765                 let channel = Channel::new_outbound(&self.fee_estimator, &self.keys_manager, their_network_key, channel_value_satoshis, push_msat, user_id, config)?;
 766                 let res = channel.get_open_channel(self.genesis_hash.clone());
 767
 768                 let _ = self.total_consistency_lock.read().unwrap();
 769                 let mut channel_state = self.channel_state.lock().unwrap();
 770                 match channel_state.by_id.entry(channel.channel_id()) {
 771                         hash_map::Entry::Occupied(_) => {
 772                                 if cfg!(feature = "fuzztarget") {
 773                                         return Err(APIError::APIMisuseError { err: "Fuzzy bad RNG".to_owned() });
 774                                 } else {
 775                                         panic!("RNG is bad???");
 776                                 }
 777                         },
 778                         hash_map::Entry::Vacant(entry) => { entry.insert(channel); }
 779                 }
 780                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendOpenChannel {
 781                         node_id: their_network_key,
 782                         msg: res,
 783                 });
 784                 Ok(())
 785         }
 786
 787         fn list_channels_with_filter<Fn: FnMut(&(&[u8; 32], &Channel<ChanSigner>)) -> bool>(&self, f: Fn) -> Vec<ChannelDetails> {
 788                 let mut res = Vec::new();
 789                 {
 790                         let channel_state = self.channel_state.lock().unwrap();
 791                         res.reserve(channel_state.by_id.len());
 792                         for (channel_id, channel) in channel_state.by_id.iter().filter(f) {
 793                                 let (inbound_capacity_msat, outbound_capacity_msat) = channel.get_inbound_outbound_available_balance_msat();
 794                                 res.push(ChannelDetails {
 795                                         channel_id: (*channel_id).clone(),
 796                                         short_channel_id: channel.get_short_channel_id(),
 797                                         remote_network_id: channel.get_their_node_id(),
 798                                         counterparty_features: InitFeatures::empty(),
 799                                         channel_value_satoshis: channel.get_value_satoshis(),
 800                                         inbound_capacity_msat,
 801                                         outbound_capacity_msat,
 802                                         user_id: channel.get_user_id(),
 803                                         is_live: channel.is_live(),
 804                                 });
 805                         }
 806                 }
 807                 let per_peer_state = self.per_peer_state.read().unwrap();
 808                 for chan in res.iter_mut() {
 809                         if let Some(peer_state) = per_peer_state.get(&chan.remote_network_id) {
 810                                 chan.counterparty_features = peer_state.lock().unwrap().latest_features.clone();
 811                         }
 812                 }
 813                 res
 814         }
 815
 816         /// Gets the list of open channels, in random order. See ChannelDetail field documentation for
 817         /// more information.
 818         pub fn list_channels(&self) -> Vec<ChannelDetails> {
 819                 self.list_channels_with_filter(|_| true)
 820         }
 821
 822         /// Gets the list of usable channels, in random order. Useful as an argument to
 823         /// get_route to ensure non-announced channels are used.
 824         ///
 825         /// These are guaranteed to have their is_live value set to true, see the documentation for
 826         /// ChannelDetails::is_live for more info on exactly what the criteria are.
 827         pub fn list_usable_channels(&self) -> Vec<ChannelDetails> {
 828                 // Note we use is_live here instead of usable which leads to somewhat confused
 829                 // internal/external nomenclature, but that's ok cause that's probably what the user
 830                 // really wanted anyway.
 831                 self.list_channels_with_filter(|&(_, ref channel)| channel.is_live())
 832         }
 833
 834         /// Begins the process of closing a channel. After this call (plus some timeout), no new HTLCs
 835         /// will be accepted on the given channel, and after additional timeout/the closing of all
 836         /// pending HTLCs, the channel will be closed on chain.
 837         ///
 838         /// May generate a SendShutdown message event on success, which should be relayed.
 839         pub fn close_channel(&self, channel_id: &[u8; 32]) -> Result<(), APIError> {
 840                 let _ = self.total_consistency_lock.read().unwrap();
 841
 842                 let (mut failed_htlcs, chan_option) = {
 843                         let mut channel_state_lock = self.channel_state.lock().unwrap();
 844                         let channel_state = &mut *channel_state_lock;
 845                         match channel_state.by_id.entry(channel_id.clone()) {
 846                                 hash_map::Entry::Occupied(mut chan_entry) => {
 847                                         let (shutdown_msg, failed_htlcs) = chan_entry.get_mut().get_shutdown()?;
 848                                         channel_state.pending_msg_events.push(events::MessageSendEvent::SendShutdown {
 849                                                 node_id: chan_entry.get().get_their_node_id(),
 850                                                 msg: shutdown_msg
 851                                         });
 852                                         if chan_entry.get().is_shutdown() {
 853                                                 if let Some(short_id) = chan_entry.get().get_short_channel_id() {
 854                                                         channel_state.short_to_id.remove(&short_id);
 855                                                 }
 856                                                 (failed_htlcs, Some(chan_entry.remove_entry().1))
 857                                         } else { (failed_htlcs, None) }
 858                                 },
 859                                 hash_map::Entry::Vacant(_) => return Err(APIError::ChannelUnavailable{err: "No such channel".to_owned()})
 860                         }
 861                 };
 862                 for htlc_source in failed_htlcs.drain(..) {
 863                         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() });
 864                 }
 865                 let chan_update = if let Some(chan) = chan_option {
 866                         if let Ok(update) = self.get_channel_update(&chan) {
 867                                 Some(update)
 868                         } else { None }
 869                 } else { None };
 870
 871                 if let Some(update) = chan_update {
 872                         let mut channel_state = self.channel_state.lock().unwrap();
 873                         channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
 874                                 msg: update
 875                         });
 876                 }
 877
 878                 Ok(())
 879         }
 880
 881         #[inline]
 882         fn finish_force_close_channel(&self, shutdown_res: ShutdownResult) {
 883                 let (funding_txo_option, monitor_update, mut failed_htlcs) = shutdown_res;
 884                 log_trace!(self.logger, "Finishing force-closure of channel {} HTLCs to fail", failed_htlcs.len());
 885                 for htlc_source in failed_htlcs.drain(..) {
 886                         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() });
 887                 }
 888                 if let Some(funding_txo) = funding_txo_option {
 889                         // There isn't anything we can do if we get an update failure - we're already
 890                         // force-closing. The monitor update on the required in-memory copy should broadcast
 891                         // the latest local state, which is the best we can do anyway. Thus, it is safe to
 892                         // ignore the result here.
 893                         let _ = self.monitor.update_monitor(funding_txo, monitor_update);
 894                 }
 895         }
 896
 897         /// Force closes a channel, immediately broadcasting the latest local commitment transaction to
 898         /// the chain and rejecting new HTLCs on the given channel.
 899         pub fn force_close_channel(&self, channel_id: &[u8; 32]) {
 900                 let _ = self.total_consistency_lock.read().unwrap();
 901
 902                 let mut chan = {
 903                         let mut channel_state_lock = self.channel_state.lock().unwrap();
 904                         let channel_state = &mut *channel_state_lock;
 905                         if let Some(chan) = channel_state.by_id.remove(channel_id) {
 906                                 if let Some(short_id) = chan.get_short_channel_id() {
 907                                         channel_state.short_to_id.remove(&short_id);
 908                                 }
 909                                 chan
 910                         } else {
 911                                 return;
 912                         }
 913                 };
 914                 log_trace!(self.logger, "Force-closing channel {}", log_bytes!(channel_id[..]));
 915                 self.finish_force_close_channel(chan.force_shutdown(true));
 916                 if let Ok(update) = self.get_channel_update(&chan) {
 917                         let mut channel_state = self.channel_state.lock().unwrap();
 918                         channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
 919                                 msg: update
 920                         });
 921                 }
 922         }
 923
 924         /// Force close all channels, immediately broadcasting the latest local commitment transaction
 925         /// for each to the chain and rejecting new HTLCs on each.
 926         pub fn force_close_all_channels(&self) {
 927                 for chan in self.list_channels() {
 928                         self.force_close_channel(&chan.channel_id);
 929                 }
 930         }
 931
 932         fn decode_update_add_htlc_onion(&self, msg: &msgs::UpdateAddHTLC) -> (PendingHTLCStatus, MutexGuard<ChannelHolder<ChanSigner>>) {
 933                 macro_rules! return_malformed_err {
 934                         ($msg: expr, $err_code: expr) => {
 935                                 {
 936                                         log_info!(self.logger, "Failed to accept/forward incoming HTLC: {}", $msg);
 937                                         return (PendingHTLCStatus::Fail(HTLCFailureMsg::Malformed(msgs::UpdateFailMalformedHTLC {
 938                                                 channel_id: msg.channel_id,
 939                                                 htlc_id: msg.htlc_id,
 940                                                 sha256_of_onion: Sha256::hash(&msg.onion_routing_packet.hop_data).into_inner(),
 941                                                 failure_code: $err_code,
 942                                         })), self.channel_state.lock().unwrap());
 943                                 }
 944                         }
 945                 }
 946
 947                 if let Err(_) = msg.onion_routing_packet.public_key {
 948                         return_malformed_err!("invalid ephemeral pubkey", 0x8000 | 0x4000 | 6);
 949                 }
 950
 951                 let shared_secret = {
 952                         let mut arr = [0; 32];
 953                         arr.copy_from_slice(&SharedSecret::new(&msg.onion_routing_packet.public_key.unwrap(), &self.our_network_key)[..]);
 954                         arr
 955                 };
 956                 let (rho, mu) = onion_utils::gen_rho_mu_from_shared_secret(&shared_secret);
 957
 958                 if msg.onion_routing_packet.version != 0 {
 959                         //TODO: Spec doesn't indicate if we should only hash hop_data here (and in other
 960                         //sha256_of_onion error data packets), or the entire onion_routing_packet. Either way,
 961                         //the hash doesn't really serve any purpose - in the case of hashing all data, the
 962                         //receiving node would have to brute force to figure out which version was put in the
 963                         //packet by the node that send us the message, in the case of hashing the hop_data, the
 964                         //node knows the HMAC matched, so they already know what is there...
 965                         return_malformed_err!("Unknown onion packet version", 0x8000 | 0x4000 | 4);
 966                 }
 967
 968                 let mut hmac = HmacEngine::<Sha256>::new(&mu);
 969                 hmac.input(&msg.onion_routing_packet.hop_data);
 970                 hmac.input(&msg.payment_hash.0[..]);
 971                 if !fixed_time_eq(&Hmac::from_engine(hmac).into_inner(), &msg.onion_routing_packet.hmac) {
 972                         return_malformed_err!("HMAC Check failed", 0x8000 | 0x4000 | 5);
 973                 }
 974
 975                 let mut channel_state = None;
 976                 macro_rules! return_err {
 977                         ($msg: expr, $err_code: expr, $data: expr) => {
 978                                 {
 979                                         log_info!(self.logger, "Failed to accept/forward incoming HTLC: {}", $msg);
 980                                         if channel_state.is_none() {
 981                                                 channel_state = Some(self.channel_state.lock().unwrap());
 982                                         }
 983                                         return (PendingHTLCStatus::Fail(HTLCFailureMsg::Relay(msgs::UpdateFailHTLC {
 984                                                 channel_id: msg.channel_id,
 985                                                 htlc_id: msg.htlc_id,
 986                                                 reason: onion_utils::build_first_hop_failure_packet(&shared_secret, $err_code, $data),
 987                                         })), channel_state.unwrap());
 988                                 }
 989                         }
 990                 }
 991
 992                 let mut chacha = ChaCha20::new(&rho, &[0u8; 8]);
 993                 let mut chacha_stream = ChaChaReader { chacha: &mut chacha, read: Cursor::new(&msg.onion_routing_packet.hop_data[..]) };
 994                 let (next_hop_data, next_hop_hmac) = {
 995                         match msgs::OnionHopData::read(&mut chacha_stream) {
 996                                 Err(err) => {
 997                                         let error_code = match err {
 998                                                 msgs::DecodeError::UnknownVersion => 0x4000 | 1, // unknown realm byte
 999                                                 msgs::DecodeError::UnknownRequiredFeature|
1000                                                 msgs::DecodeError::InvalidValue|
1001                                                 msgs::DecodeError::ShortRead => 0x4000 | 22, // invalid_onion_payload
1002                                                 _ => 0x2000 | 2, // Should never happen
1003                                         };
1004                                         return_err!("Unable to decode our hop data", error_code, &[0;0]);
1005                                 },
1006                                 Ok(msg) => {
1007                                         let mut hmac = [0; 32];
1008                                         if let Err(_) = chacha_stream.read_exact(&mut hmac[..]) {
1009                                                 return_err!("Unable to decode hop data", 0x4000 | 22, &[0;0]);
1010                                         }
1011                                         (msg, hmac)
1012                                 },
1013                         }
1014                 };
1015
1016                 let pending_forward_info = if next_hop_hmac == [0; 32] {
1017                                 #[cfg(test)]
1018                                 {
1019                                         // In tests, make sure that the initial onion pcket data is, at least, non-0.
1020                                         // We could do some fancy randomness test here, but, ehh, whatever.
1021                                         // This checks for the issue where you can calculate the path length given the
1022                                         // onion data as all the path entries that the originator sent will be here
1023                                         // as-is (and were originally 0s).
1024                                         // Of course reverse path calculation is still pretty easy given naive routing
1025                                         // algorithms, but this fixes the most-obvious case.
1026                                         let mut next_bytes = [0; 32];
1027                                         chacha_stream.read_exact(&mut next_bytes).unwrap();
1028                                         assert_ne!(next_bytes[..], [0; 32][..]);
1029                                         chacha_stream.read_exact(&mut next_bytes).unwrap();
1030                                         assert_ne!(next_bytes[..], [0; 32][..]);
1031                                 }
1032
1033                                 // OUR PAYMENT!
1034                                 // final_expiry_too_soon
1035                                 // We have to have some headroom to broadcast on chain if we have the preimage, so make sure we have at least
1036                                 // HTLC_FAIL_BACK_BUFFER blocks to go.
1037                                 // Also, ensure that, in the case of an unknown payment hash, our payment logic has enough time to fail the HTLC backward
1038                                 // before our onchain logic triggers a channel closure (see HTLC_FAIL_BACK_BUFFER rational).
1039                                 if (msg.cltv_expiry as u64) <= self.latest_block_height.load(Ordering::Acquire) as u64 + HTLC_FAIL_BACK_BUFFER as u64 + 1 {
1040                                         return_err!("The final CLTV expiry is too soon to handle", 17, &[0;0]);
1041                                 }
1042                                 // final_incorrect_htlc_amount
1043                                 if next_hop_data.amt_to_forward > msg.amount_msat {
1044                                         return_err!("Upstream node sent less than we were supposed to receive in payment", 19, &byte_utils::be64_to_array(msg.amount_msat));
1045                                 }
1046                                 // final_incorrect_cltv_expiry
1047                                 if next_hop_data.outgoing_cltv_value != msg.cltv_expiry {
1048                                         return_err!("Upstream node set CLTV to the wrong value", 18, &byte_utils::be32_to_array(msg.cltv_expiry));
1049                                 }
1050
1051                                 let payment_data = match next_hop_data.format {
1052                                         msgs::OnionHopDataFormat::Legacy { .. } => None,
1053                                         msgs::OnionHopDataFormat::NonFinalNode { .. } => return_err!("Got non final data with an HMAC of 0", 0x4000 | 22, &[0;0]),
1054                                         msgs::OnionHopDataFormat::FinalNode { payment_data } => payment_data,
1055                                 };
1056
1057                                 // Note that we could obviously respond immediately with an update_fulfill_htlc
1058                                 // message, however that would leak that we are the recipient of this payment, so
1059                                 // instead we stay symmetric with the forwarding case, only responding (after a
1060                                 // delay) once they've send us a commitment_signed!
1061
1062                                 PendingHTLCStatus::Forward(PendingHTLCInfo {
1063                                         routing: PendingHTLCRouting::Receive {
1064                                                 payment_data,
1065                                                 incoming_cltv_expiry: msg.cltv_expiry,
1066                                         },
1067                                         payment_hash: msg.payment_hash.clone(),
1068                                         incoming_shared_secret: shared_secret,
1069                                         amt_to_forward: next_hop_data.amt_to_forward,
1070                                         outgoing_cltv_value: next_hop_data.outgoing_cltv_value,
1071                                 })
1072                         } else {
1073                                 let mut new_packet_data = [0; 20*65];
1074                                 let read_pos = chacha_stream.read(&mut new_packet_data).unwrap();
1075                                 #[cfg(debug_assertions)]
1076                                 {
1077                                         // Check two things:
1078                                         // a) that the behavior of our stream here will return Ok(0) even if the TLV
1079                                         //    read above emptied out our buffer and the unwrap() wont needlessly panic
1080                                         // b) that we didn't somehow magically end up with extra data.
1081                                         let mut t = [0; 1];
1082                                         debug_assert!(chacha_stream.read(&mut t).unwrap() == 0);
1083                                 }
1084                                 // Once we've emptied the set of bytes our peer gave us, encrypt 0 bytes until we
1085                                 // fill the onion hop data we'll forward to our next-hop peer.
1086                                 chacha_stream.chacha.process_in_place(&mut new_packet_data[read_pos..]);
1087
1088                                 let mut new_pubkey = msg.onion_routing_packet.public_key.unwrap();
1089
1090                                 let blinding_factor = {
1091                                         let mut sha = Sha256::engine();
1092                                         sha.input(&new_pubkey.serialize()[..]);
1093                                         sha.input(&shared_secret);
1094                                         Sha256::from_engine(sha).into_inner()
1095                                 };
1096
1097                                 let public_key = if let Err(e) = new_pubkey.mul_assign(&self.secp_ctx, &blinding_factor[..]) {
1098                                         Err(e)
1099                                 } else { Ok(new_pubkey) };
1100
1101                                 let outgoing_packet = msgs::OnionPacket {
1102                                         version: 0,
1103                                         public_key,
1104                                         hop_data: new_packet_data,
1105                                         hmac: next_hop_hmac.clone(),
1106                                 };
1107
1108                                 let short_channel_id = match next_hop_data.format {
1109                                         msgs::OnionHopDataFormat::Legacy { short_channel_id } => short_channel_id,
1110                                         msgs::OnionHopDataFormat::NonFinalNode { short_channel_id } => short_channel_id,
1111                                         msgs::OnionHopDataFormat::FinalNode { .. } => {
1112                                                 return_err!("Final Node OnionHopData provided for us as an intermediary node", 0x4000 | 22, &[0;0]);
1113                                         },
1114                                 };
1115
1116                                 PendingHTLCStatus::Forward(PendingHTLCInfo {
1117                                         routing: PendingHTLCRouting::Forward {
1118                                                 onion_packet: outgoing_packet,
1119                                                 short_channel_id: short_channel_id,
1120                                         },
1121                                         payment_hash: msg.payment_hash.clone(),
1122                                         incoming_shared_secret: shared_secret,
1123                                         amt_to_forward: next_hop_data.amt_to_forward,
1124                                         outgoing_cltv_value: next_hop_data.outgoing_cltv_value,
1125                                 })
1126                         };
1127
1128                 channel_state = Some(self.channel_state.lock().unwrap());
1129                 if let &PendingHTLCStatus::Forward(PendingHTLCInfo { ref routing, ref amt_to_forward, ref outgoing_cltv_value, .. }) = &pending_forward_info {
1130                         // If short_channel_id is 0 here, we'll reject the HTLC as there cannot be a channel
1131                         // with a short_channel_id of 0. This is important as various things later assume
1132                         // short_channel_id is non-0 in any ::Forward.
1133                         if let &PendingHTLCRouting::Forward { ref short_channel_id, .. } = routing {
1134                                 let id_option = channel_state.as_ref().unwrap().short_to_id.get(&short_channel_id).cloned();
1135                                 let forwarding_id = match id_option {
1136                                         None => { // unknown_next_peer
1137                                                 return_err!("Don't have available channel for forwarding as requested.", 0x4000 | 10, &[0;0]);
1138                                         },
1139                                         Some(id) => id.clone(),
1140                                 };
1141                                 if let Some((err, code, chan_update)) = loop {
1142                                         let chan = channel_state.as_mut().unwrap().by_id.get_mut(&forwarding_id).unwrap();
1143
1144                                         // Note that we could technically not return an error yet here and just hope
1145                                         // that the connection is reestablished or monitor updated by the time we get
1146                                         // around to doing the actual forward, but better to fail early if we can and
1147                                         // hopefully an attacker trying to path-trace payments cannot make this occur
1148                                         // on a small/per-node/per-channel scale.
1149                                         if !chan.is_live() { // channel_disabled
1150                                                 break Some(("Forwarding channel is not in a ready state.", 0x1000 | 20, Some(self.get_channel_update(chan).unwrap())));
1151                                         }
1152                                         if *amt_to_forward < chan.get_their_htlc_minimum_msat() { // amount_below_minimum
1153                                                 break Some(("HTLC amount was below the htlc_minimum_msat", 0x1000 | 11, Some(self.get_channel_update(chan).unwrap())));
1154                                         }
1155                                         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) });
1156                                         if fee.is_none() || msg.amount_msat < fee.unwrap() || (msg.amount_msat - fee.unwrap()) < *amt_to_forward { // fee_insufficient
1157                                                 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())));
1158                                         }
1159                                         if (msg.cltv_expiry as u64) < (*outgoing_cltv_value) as u64 + CLTV_EXPIRY_DELTA as u64 { // incorrect_cltv_expiry
1160                                                 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())));
1161                                         }
1162                                         let cur_height = self.latest_block_height.load(Ordering::Acquire) as u32 + 1;
1163                                         // Theoretically, channel counterparty shouldn't send us a HTLC expiring now, but we want to be robust wrt to counterparty
1164                                         // packet sanitization (see HTLC_FAIL_BACK_BUFFER rational)
1165                                         if msg.cltv_expiry <= cur_height + HTLC_FAIL_BACK_BUFFER as u32 { // expiry_too_soon
1166                                                 break Some(("CLTV expiry is too close", 0x1000 | 14, Some(self.get_channel_update(chan).unwrap())));
1167                                         }
1168                                         if msg.cltv_expiry > cur_height + CLTV_FAR_FAR_AWAY as u32 { // expiry_too_far
1169                                                 break Some(("CLTV expiry is too far in the future", 21, None));
1170                                         }
1171                                         // In theory, we would be safe against unitentional channel-closure, if we only required a margin of LATENCY_GRACE_PERIOD_BLOCKS.
1172                                         // But, to be safe against policy reception, we use a longuer delay.
1173                                         if (*outgoing_cltv_value) as u64 <= (cur_height + HTLC_FAIL_BACK_BUFFER) as u64 {
1174                                                 break Some(("Outgoing CLTV value is too soon", 0x1000 | 14, Some(self.get_channel_update(chan).unwrap())));
1175                                         }
1176
1177                                         break None;
1178                                 }
1179                                 {
1180                                         let mut res = Vec::with_capacity(8 + 128);
1181                                         if let Some(chan_update) = chan_update {
1182                                                 if code == 0x1000 | 11 || code == 0x1000 | 12 {
1183                                                         res.extend_from_slice(&byte_utils::be64_to_array(msg.amount_msat));
1184                                                 }
1185                                                 else if code == 0x1000 | 13 {
1186                                                         res.extend_from_slice(&byte_utils::be32_to_array(msg.cltv_expiry));
1187                                                 }
1188                                                 else if code == 0x1000 | 20 {
1189                                                         // TODO: underspecified, follow https://github.com/lightningnetwork/lightning-rfc/issues/791
1190                                                         res.extend_from_slice(&byte_utils::be16_to_array(0));
1191                                                 }
1192                                                 res.extend_from_slice(&chan_update.encode_with_len()[..]);
1193                                         }
1194                                         return_err!(err, code, &res[..]);
1195                                 }
1196                         }
1197                 }
1198
1199                 (pending_forward_info, channel_state.unwrap())
1200         }
1201
1202         /// only fails if the channel does not yet have an assigned short_id
1203         /// May be called with channel_state already locked!
1204         fn get_channel_update(&self, chan: &Channel<ChanSigner>) -> Result<msgs::ChannelUpdate, LightningError> {
1205                 let short_channel_id = match chan.get_short_channel_id() {
1206                         None => return Err(LightningError{err: "Channel not yet established".to_owned(), action: msgs::ErrorAction::IgnoreError}),
1207                         Some(id) => id,
1208                 };
1209
1210                 let were_node_one = PublicKey::from_secret_key(&self.secp_ctx, &self.our_network_key).serialize()[..] < chan.get_their_node_id().serialize()[..];
1211
1212                 let unsigned = msgs::UnsignedChannelUpdate {
1213                         chain_hash: self.genesis_hash,
1214                         short_channel_id: short_channel_id,
1215                         timestamp: chan.get_update_time_counter(),
1216                         flags: (!were_node_one) as u8 | ((!chan.is_live() as u8) << 1),
1217                         cltv_expiry_delta: CLTV_EXPIRY_DELTA,
1218                         htlc_minimum_msat: chan.get_our_htlc_minimum_msat(),
1219                         htlc_maximum_msat: OptionalField::Present(chan.get_announced_htlc_max_msat()),
1220                         fee_base_msat: chan.get_our_fee_base_msat(&self.fee_estimator),
1221                         fee_proportional_millionths: chan.get_fee_proportional_millionths(),
1222                         excess_data: Vec::new(),
1223                 };
1224
1225                 let msg_hash = Sha256dHash::hash(&unsigned.encode()[..]);
1226                 let sig = self.secp_ctx.sign(&hash_to_message!(&msg_hash[..]), &self.our_network_key);
1227
1228                 Ok(msgs::ChannelUpdate {
1229                         signature: sig,
1230                         contents: unsigned
1231                 })
1232         }
1233
1234         // Only public for testing, this should otherwise never be called direcly
1235         pub(crate) fn send_payment_along_path(&self, path: &Vec<RouteHop>, payment_hash: &PaymentHash, payment_secret: &Option<PaymentSecret>, total_value: u64, cur_height: u32) -> Result<(), APIError> {
1236                 log_trace!(self.logger, "Attempting to send payment for path with next hop {}", path.first().unwrap().short_channel_id);
1237                 let (session_priv, prng_seed) = self.keys_manager.get_onion_rand();
1238
1239                 let onion_keys = onion_utils::construct_onion_keys(&self.secp_ctx, &path, &session_priv)
1240                         .map_err(|_| APIError::RouteError{err: "Pubkey along hop was maliciously selected"})?;
1241                 let (onion_payloads, htlc_msat, htlc_cltv) = onion_utils::build_onion_payloads(path, total_value, payment_secret, cur_height)?;
1242                 if onion_utils::route_size_insane(&onion_payloads) {
1243                         return Err(APIError::RouteError{err: "Route size too large considering onion data"});
1244                 }
1245                 let onion_packet = onion_utils::construct_onion_packet(onion_payloads, onion_keys, prng_seed, payment_hash);
1246
1247                 let _ = self.total_consistency_lock.read().unwrap();
1248
1249                 let err: Result<(), _> = loop {
1250                         let mut channel_lock = self.channel_state.lock().unwrap();
1251                         let id = match channel_lock.short_to_id.get(&path.first().unwrap().short_channel_id) {
1252                                 None => return Err(APIError::ChannelUnavailable{err: "No channel available with first hop!".to_owned()}),
1253                                 Some(id) => id.clone(),
1254                         };
1255
1256                         let channel_state = &mut *channel_lock;
1257                         if let hash_map::Entry::Occupied(mut chan) = channel_state.by_id.entry(id) {
1258                                 match {
1259                                         if chan.get().get_their_node_id() != path.first().unwrap().pubkey {
1260                                                 return Err(APIError::RouteError{err: "Node ID mismatch on first hop!"});
1261                                         }
1262                                         if !chan.get().is_live() {
1263                                                 return Err(APIError::ChannelUnavailable{err: "Peer for first hop currently disconnected/pending monitor update!".to_owned()});
1264                                         }
1265                                         break_chan_entry!(self, chan.get_mut().send_htlc_and_commit(htlc_msat, payment_hash.clone(), htlc_cltv, HTLCSource::OutboundRoute {
1266                                                 path: path.clone(),
1267                                                 session_priv: session_priv.clone(),
1268                                                 first_hop_htlc_msat: htlc_msat,
1269                                         }, onion_packet, &self.logger), channel_state, chan)
1270                                 } {
1271                                         Some((update_add, commitment_signed, monitor_update)) => {
1272                                                 if let Err(e) = self.monitor.update_monitor(chan.get().get_funding_txo().unwrap(), monitor_update) {
1273                                                         maybe_break_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::CommitmentFirst, false, true);
1274                                                         // Note that MonitorUpdateFailed here indicates (per function docs)
1275                                                         // that we will resend the commitment update once monitor updating
1276                                                         // is restored. Therefore, we must return an error indicating that
1277                                                         // it is unsafe to retry the payment wholesale, which we do in the
1278                                                         // send_payment check for MonitorUpdateFailed, below.
1279                                                         return Err(APIError::MonitorUpdateFailed);
1280                                                 }
1281
1282                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
1283                                                         node_id: path.first().unwrap().pubkey,
1284                                                         updates: msgs::CommitmentUpdate {
1285                                                                 update_add_htlcs: vec![update_add],
1286                                                                 update_fulfill_htlcs: Vec::new(),
1287                                                                 update_fail_htlcs: Vec::new(),
1288                                                                 update_fail_malformed_htlcs: Vec::new(),
1289                                                                 update_fee: None,
1290                                                                 commitment_signed,
1291                                                         },
1292                                                 });
1293                                         },
1294                                         None => {},
1295                                 }
1296                         } else { unreachable!(); }
1297                         return Ok(());
1298                 };
1299
1300                 match handle_error!(self, err, path.first().unwrap().pubkey) {
1301                         Ok(_) => unreachable!(),
1302                         Err(e) => {
1303                                 Err(APIError::ChannelUnavailable { err: e.err })
1304                         },
1305                 }
1306         }
1307
1308         /// Sends a payment along a given route.
1309         ///
1310         /// Value parameters are provided via the last hop in route, see documentation for RouteHop
1311         /// fields for more info.
1312         ///
1313         /// Note that if the payment_hash already exists elsewhere (eg you're sending a duplicative
1314         /// payment), we don't do anything to stop you! We always try to ensure that if the provided
1315         /// next hop knows the preimage to payment_hash they can claim an additional amount as
1316         /// specified in the last hop in the route! Thus, you should probably do your own
1317         /// payment_preimage tracking (which you should already be doing as they represent "proof of
1318         /// payment") and prevent double-sends yourself.
1319         ///
1320         /// May generate SendHTLCs message(s) event on success, which should be relayed.
1321         ///
1322         /// Each path may have a different return value, and PaymentSendValue may return a Vec with
1323         /// each entry matching the corresponding-index entry in the route paths, see
1324         /// PaymentSendFailure for more info.
1325         ///
1326         /// In general, a path may raise:
1327         ///  * APIError::RouteError when an invalid route or forwarding parameter (cltv_delta, fee,
1328         ///    node public key) is specified.
1329         ///  * APIError::ChannelUnavailable if the next-hop channel is not available for updates
1330         ///    (including due to previous monitor update failure or new permanent monitor update
1331         ///    failure).
1332         ///  * APIError::MonitorUpdateFailed if a new monitor update failure prevented sending the
1333         ///    relevant updates.
1334         ///
1335         /// Note that depending on the type of the PaymentSendFailure the HTLC may have been
1336         /// irrevocably committed to on our end. In such a case, do NOT retry the payment with a
1337         /// different route unless you intend to pay twice!
1338         ///
1339         /// payment_secret is unrelated to payment_hash (or PaymentPreimage) and exists to authenticate
1340         /// the sender to the recipient and prevent payment-probing (deanonymization) attacks. For
1341         /// newer nodes, it will be provided to you in the invoice. If you do not have one, the Route
1342         /// must not contain multiple paths as multi-path payments require a recipient-provided
1343         /// payment_secret.
1344         /// If a payment_secret *is* provided, we assume that the invoice had the payment_secret feature
1345         /// bit set (either as required or as available). If multiple paths are present in the Route,
1346         /// we assume the invoice had the basic_mpp feature set.
1347         pub fn send_payment(&self, route: &Route, payment_hash: PaymentHash, payment_secret: &Option<PaymentSecret>) -> Result<(), PaymentSendFailure> {
1348                 if route.paths.len() < 1 {
1349                         return Err(PaymentSendFailure::ParameterError(APIError::RouteError{err: "There must be at least one path to send over"}));
1350                 }
1351                 if route.paths.len() > 10 {
1352                         // This limit is completely arbitrary - there aren't any real fundamental path-count
1353                         // limits. After we support retrying individual paths we should likely bump this, but
1354                         // for now more than 10 paths likely carries too much one-path failure.
1355                         return Err(PaymentSendFailure::ParameterError(APIError::RouteError{err: "Sending over more than 10 paths is not currently supported"}));
1356                 }
1357                 let mut total_value = 0;
1358                 let our_node_id = self.get_our_node_id();
1359                 let mut path_errs = Vec::with_capacity(route.paths.len());
1360                 'path_check: for path in route.paths.iter() {
1361                         if path.len() < 1 || path.len() > 20 {
1362                                 path_errs.push(Err(APIError::RouteError{err: "Path didn't go anywhere/had bogus size"}));
1363                                 continue 'path_check;
1364                         }
1365                         for (idx, hop) in path.iter().enumerate() {
1366                                 if idx != path.len() - 1 && hop.pubkey == our_node_id {
1367                                         path_errs.push(Err(APIError::RouteError{err: "Path went through us but wasn't a simple rebalance loop to us"}));
1368                                         continue 'path_check;
1369                                 }
1370                         }
1371                         total_value += path.last().unwrap().fee_msat;
1372                         path_errs.push(Ok(()));
1373                 }
1374                 if path_errs.iter().any(|e| e.is_err()) {
1375                         return Err(PaymentSendFailure::PathParameterError(path_errs));
1376                 }
1377
1378                 let cur_height = self.latest_block_height.load(Ordering::Acquire) as u32 + 1;
1379                 let mut results = Vec::new();
1380                 for path in route.paths.iter() {
1381                         results.push(self.send_payment_along_path(&path, &payment_hash, payment_secret, total_value, cur_height));
1382                 }
1383                 let mut has_ok = false;
1384                 let mut has_err = false;
1385                 for res in results.iter() {
1386                         if res.is_ok() { has_ok = true; }
1387                         if res.is_err() { has_err = true; }
1388                         if let &Err(APIError::MonitorUpdateFailed) = res {
1389                                 // MonitorUpdateFailed is inherently unsafe to retry, so we call it a
1390                                 // PartialFailure.
1391                                 has_err = true;
1392                                 has_ok = true;
1393                                 break;
1394                         }
1395                 }
1396                 if has_err && has_ok {
1397                         Err(PaymentSendFailure::PartialFailure(results))
1398                 } else if has_err {
1399                         Err(PaymentSendFailure::AllFailedRetrySafe(results.drain(..).map(|r| r.unwrap_err()).collect()))
1400                 } else {
1401                         Ok(())
1402                 }
1403         }
1404
1405         /// Call this upon creation of a funding transaction for the given channel.
1406         ///
1407         /// Note that ALL inputs in the transaction pointed to by funding_txo MUST spend SegWit outputs
1408         /// or your counterparty can steal your funds!
1409         ///
1410         /// Panics if a funding transaction has already been provided for this channel.
1411         ///
1412         /// May panic if the funding_txo is duplicative with some other channel (note that this should
1413         /// be trivially prevented by using unique funding transaction keys per-channel).
1414         pub fn funding_transaction_generated(&self, temporary_channel_id: &[u8; 32], funding_txo: OutPoint) {
1415                 let _ = self.total_consistency_lock.read().unwrap();
1416
1417                 let (chan, msg) = {
1418                         let (res, chan) = match self.channel_state.lock().unwrap().by_id.remove(temporary_channel_id) {
1419                                 Some(mut chan) => {
1420                                         (chan.get_outbound_funding_created(funding_txo, &self.logger)
1421                                                 .map_err(|e| if let ChannelError::Close(msg) = e {
1422                                                         MsgHandleErrInternal::from_finish_shutdown(msg, chan.channel_id(), chan.force_shutdown(true), None)
1423                                                 } else { unreachable!(); })
1424                                         , chan)
1425                                 },
1426                                 None => return
1427                         };
1428                         match handle_error!(self, res, chan.get_their_node_id()) {
1429                                 Ok(funding_msg) => {
1430                                         (chan, funding_msg)
1431                                 },
1432                                 Err(_) => { return; }
1433                         }
1434                 };
1435
1436                 let mut channel_state = self.channel_state.lock().unwrap();
1437                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendFundingCreated {
1438                         node_id: chan.get_their_node_id(),
1439                         msg: msg,
1440                 });
1441                 match channel_state.by_id.entry(chan.channel_id()) {
1442                         hash_map::Entry::Occupied(_) => {
1443                                 panic!("Generated duplicate funding txid?");
1444                         },
1445                         hash_map::Entry::Vacant(e) => {
1446                                 e.insert(chan);
1447                         }
1448                 }
1449         }
1450
1451         fn get_announcement_sigs(&self, chan: &Channel<ChanSigner>) -> Option<msgs::AnnouncementSignatures> {
1452                 if !chan.should_announce() {
1453                         log_trace!(self.logger, "Can't send announcement_signatures for private channel {}", log_bytes!(chan.channel_id()));
1454                         return None
1455                 }
1456
1457                 let (announcement, our_bitcoin_sig) = match chan.get_channel_announcement(self.get_our_node_id(), self.genesis_hash.clone()) {
1458                         Ok(res) => res,
1459                         Err(_) => return None, // Only in case of state precondition violations eg channel is closing
1460                 };
1461                 let msghash = hash_to_message!(&Sha256dHash::hash(&announcement.encode()[..])[..]);
1462                 let our_node_sig = self.secp_ctx.sign(&msghash, &self.our_network_key);
1463
1464                 Some(msgs::AnnouncementSignatures {
1465                         channel_id: chan.channel_id(),
1466                         short_channel_id: chan.get_short_channel_id().unwrap(),
1467                         node_signature: our_node_sig,
1468                         bitcoin_signature: our_bitcoin_sig,
1469                 })
1470         }
1471
1472         #[allow(dead_code)]
1473         // Messages of up to 64KB should never end up more than half full with addresses, as that would
1474         // be absurd. We ensure this by checking that at least 500 (our stated public contract on when
1475         // broadcast_node_announcement panics) of the maximum-length addresses would fit in a 64KB
1476         // message...
1477         const HALF_MESSAGE_IS_ADDRS: u32 = ::std::u16::MAX as u32 / (msgs::NetAddress::MAX_LEN as u32 + 1) / 2;
1478         #[deny(const_err)]
1479         #[allow(dead_code)]
1480         // ...by failing to compile if the number of addresses that would be half of a message is
1481         // smaller than 500:
1482         const STATIC_ASSERT: u32 = Self::HALF_MESSAGE_IS_ADDRS - 500;
1483
1484         /// Generates a signed node_announcement from the given arguments and creates a
1485         /// BroadcastNodeAnnouncement event. Note that such messages will be ignored unless peers have
1486         /// seen a channel_announcement from us (ie unless we have public channels open).
1487         ///
1488         /// RGB is a node "color" and alias is a printable human-readable string to describe this node
1489         /// to humans. They carry no in-protocol meaning.
1490         ///
1491         /// addresses represent the set (possibly empty) of socket addresses on which this node accepts
1492         /// incoming connections. These will be broadcast to the network, publicly tying these
1493         /// addresses together. If you wish to preserve user privacy, addresses should likely contain
1494         /// only Tor Onion addresses.
1495         ///
1496         /// Panics if addresses is absurdly large (more than 500).
1497         pub fn broadcast_node_announcement(&self, rgb: [u8; 3], alias: [u8; 32], addresses: Vec<msgs::NetAddress>) {
1498                 let _ = self.total_consistency_lock.read().unwrap();
1499
1500                 if addresses.len() > 500 {
1501                         panic!("More than half the message size was taken up by public addresses!");
1502                 }
1503
1504                 let announcement = msgs::UnsignedNodeAnnouncement {
1505                         features: NodeFeatures::known(),
1506                         timestamp: self.last_node_announcement_serial.fetch_add(1, Ordering::AcqRel) as u32,
1507                         node_id: self.get_our_node_id(),
1508                         rgb, alias, addresses,
1509                         excess_address_data: Vec::new(),
1510                         excess_data: Vec::new(),
1511                 };
1512                 let msghash = hash_to_message!(&Sha256dHash::hash(&announcement.encode()[..])[..]);
1513
1514                 let mut channel_state = self.channel_state.lock().unwrap();
1515                 channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastNodeAnnouncement {
1516                         msg: msgs::NodeAnnouncement {
1517                                 signature: self.secp_ctx.sign(&msghash, &self.our_network_key),
1518                                 contents: announcement
1519                         },
1520                 });
1521         }
1522
1523         /// Processes HTLCs which are pending waiting on random forward delay.
1524         ///
1525         /// Should only really ever be called in response to a PendingHTLCsForwardable event.
1526         /// Will likely generate further events.
1527         pub fn process_pending_htlc_forwards(&self) {
1528                 let _ = self.total_consistency_lock.read().unwrap();
1529
1530                 let mut new_events = Vec::new();
1531                 let mut failed_forwards = Vec::new();
1532                 let mut handle_errors = Vec::new();
1533                 {
1534                         let mut channel_state_lock = self.channel_state.lock().unwrap();
1535                         let channel_state = &mut *channel_state_lock;
1536
1537                         for (short_chan_id, mut pending_forwards) in channel_state.forward_htlcs.drain() {
1538                                 if short_chan_id != 0 {
1539                                         let forward_chan_id = match channel_state.short_to_id.get(&short_chan_id) {
1540                                                 Some(chan_id) => chan_id.clone(),
1541                                                 None => {
1542                                                         failed_forwards.reserve(pending_forwards.len());
1543                                                         for forward_info in pending_forwards.drain(..) {
1544                                                                 match forward_info {
1545                                                                         HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info } => {
1546                                                                                 let htlc_source = HTLCSource::PreviousHopData(HTLCPreviousHopData {
1547                                                                                         short_channel_id: prev_short_channel_id,
1548                                                                                         htlc_id: prev_htlc_id,
1549                                                                                         incoming_packet_shared_secret: forward_info.incoming_shared_secret,
1550                                                                                 });
1551                                                                                 failed_forwards.push((htlc_source, forward_info.payment_hash,
1552                                                                                         HTLCFailReason::Reason { failure_code: 0x4000 | 10, data: Vec::new() }
1553                                                                                 ));
1554                                                                         },
1555                                                                         HTLCForwardInfo::FailHTLC { .. } => {
1556                                                                                 // Channel went away before we could fail it. This implies
1557                                                                                 // the channel is now on chain and our counterparty is
1558                                                                                 // trying to broadcast the HTLC-Timeout, but that's their
1559                                                                                 // problem, not ours.
1560                                                                         }
1561                                                                 }
1562                                                         }
1563                                                         continue;
1564                                                 }
1565                                         };
1566                                         if let hash_map::Entry::Occupied(mut chan) = channel_state.by_id.entry(forward_chan_id) {
1567                                                 let mut add_htlc_msgs = Vec::new();
1568                                                 let mut fail_htlc_msgs = Vec::new();
1569                                                 for forward_info in pending_forwards.drain(..) {
1570                                                         match forward_info {
1571                                                                 HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info: PendingHTLCInfo {
1572                                                                                 routing: PendingHTLCRouting::Forward {
1573                                                                                         onion_packet, ..
1574                                                                                 }, incoming_shared_secret, payment_hash, amt_to_forward, outgoing_cltv_value }, } => {
1575                                                                         log_trace!(self.logger, "Adding HTLC from short id {} with payment_hash {} to channel with short id {} after delay", log_bytes!(payment_hash.0), prev_short_channel_id, short_chan_id);
1576                                                                         let htlc_source = HTLCSource::PreviousHopData(HTLCPreviousHopData {
1577                                                                                 short_channel_id: prev_short_channel_id,
1578                                                                                 htlc_id: prev_htlc_id,
1579                                                                                 incoming_packet_shared_secret: incoming_shared_secret,
1580                                                                         });
1581                                                                         match chan.get_mut().send_htlc(amt_to_forward, payment_hash, outgoing_cltv_value, htlc_source.clone(), onion_packet) {
1582                                                                                 Err(e) => {
1583                                                                                         if let ChannelError::Ignore(msg) = e {
1584                                                                                                 log_trace!(self.logger, "Failed to forward HTLC with payment_hash {}: {}", log_bytes!(payment_hash.0), msg);
1585                                                                                         } else {
1586                                                                                                 panic!("Stated return value requirements in send_htlc() were not met");
1587                                                                                         }
1588                                                                                         let chan_update = self.get_channel_update(chan.get()).unwrap();
1589                                                                                         failed_forwards.push((htlc_source, payment_hash,
1590                                                                                                 HTLCFailReason::Reason { failure_code: 0x1000 | 7, data: chan_update.encode_with_len() }
1591                                                                                         ));
1592                                                                                         continue;
1593                                                                                 },
1594                                                                                 Ok(update_add) => {
1595                                                                                         match update_add {
1596                                                                                                 Some(msg) => { add_htlc_msgs.push(msg); },
1597                                                                                                 None => {
1598                                                                                                         // Nothing to do here...we're waiting on a remote
1599                                                                                                         // revoke_and_ack before we can add anymore HTLCs. The Channel
1600                                                                                                         // will automatically handle building the update_add_htlc and
1601                                                                                                         // commitment_signed messages when we can.
1602                                                                                                         // TODO: Do some kind of timer to set the channel as !is_live()
1603                                                                                                         // as we don't really want others relying on us relaying through
1604                                                                                                         // this channel currently :/.
1605                                                                                                 }
1606                                                                                         }
1607                                                                                 }
1608                                                                         }
1609                                                                 },
1610                                                                 HTLCForwardInfo::AddHTLC { .. } => {
1611                                                                         panic!("short_channel_id != 0 should imply any pending_forward entries are of type Forward");
1612                                                                 },
1613                                                                 HTLCForwardInfo::FailHTLC { htlc_id, err_packet } => {
1614                                                                         log_trace!(self.logger, "Failing HTLC back to channel with short id {} after delay", short_chan_id);
1615                                                                         match chan.get_mut().get_update_fail_htlc(htlc_id, err_packet) {
1616                                                                                 Err(e) => {
1617                                                                                         if let ChannelError::Ignore(msg) = e {
1618                                                                                                 log_trace!(self.logger, "Failed to fail backwards to short_id {}: {}", short_chan_id, msg);
1619                                                                                         } else {
1620                                                                                                 panic!("Stated return value requirements in get_update_fail_htlc() were not met");
1621                                                                                         }
1622                                                                                         // fail-backs are best-effort, we probably already have one
1623                                                                                         // pending, and if not that's OK, if not, the channel is on
1624                                                                                         // the chain and sending the HTLC-Timeout is their problem.
1625                                                                                         continue;
1626                                                                                 },
1627                                                                                 Ok(Some(msg)) => { fail_htlc_msgs.push(msg); },
1628                                                                                 Ok(None) => {
1629                                                                                         // Nothing to do here...we're waiting on a remote
1630                                                                                         // revoke_and_ack before we can update the commitment
1631                                                                                         // transaction. The Channel will automatically handle
1632                                                                                         // building the update_fail_htlc and commitment_signed
1633                                                                                         // messages when we can.
1634                                                                                         // We don't need any kind of timer here as they should fail
1635                                                                                         // the channel onto the chain if they can't get our
1636                                                                                         // update_fail_htlc in time, it's not our problem.
1637                                                                                 }
1638                                                                         }
1639                                                                 },
1640                                                         }
1641                                                 }
1642
1643                                                 if !add_htlc_msgs.is_empty() || !fail_htlc_msgs.is_empty() {
1644                                                         let (commitment_msg, monitor_update) = match chan.get_mut().send_commitment(&self.logger) {
1645                                                                 Ok(res) => res,
1646                                                                 Err(e) => {
1647                                                                         // We surely failed send_commitment due to bad keys, in that case
1648                                                                         // close channel and then send error message to peer.
1649                                                                         let their_node_id = chan.get().get_their_node_id();
1650                                                                         let err: Result<(), _>  = match e {
1651                                                                                 ChannelError::Ignore(_) => {
1652                                                                                         panic!("Stated return value requirements in send_commitment() were not met");
1653                                                                                 },
1654                                                                                 ChannelError::Close(msg) => {
1655                                                                                         log_trace!(self.logger, "Closing channel {} due to Close-required error: {}", log_bytes!(chan.key()[..]), msg);
1656                                                                                         let (channel_id, mut channel) = chan.remove_entry();
1657                                                                                         if let Some(short_id) = channel.get_short_channel_id() {
1658                                                                                                 channel_state.short_to_id.remove(&short_id);
1659                                                                                         }
1660                                                                                         Err(MsgHandleErrInternal::from_finish_shutdown(msg, channel_id, channel.force_shutdown(true), self.get_channel_update(&channel).ok()))
1661                                                                                 },
1662                                                                                 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"); }
1663                                                                         };
1664                                                                         handle_errors.push((their_node_id, err));
1665                                                                         continue;
1666                                                                 }
1667                                                         };
1668                                                         if let Err(e) = self.monitor.update_monitor(chan.get().get_funding_txo().unwrap(), monitor_update) {
1669                                                                 handle_errors.push((chan.get().get_their_node_id(), handle_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::CommitmentFirst, false, true)));
1670                                                                 continue;
1671                                                         }
1672                                                         channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
1673                                                                 node_id: chan.get().get_their_node_id(),
1674                                                                 updates: msgs::CommitmentUpdate {
1675                                                                         update_add_htlcs: add_htlc_msgs,
1676                                                                         update_fulfill_htlcs: Vec::new(),
1677                                                                         update_fail_htlcs: fail_htlc_msgs,
1678                                                                         update_fail_malformed_htlcs: Vec::new(),
1679                                                                         update_fee: None,
1680                                                                         commitment_signed: commitment_msg,
1681                                                                 },
1682                                                         });
1683                                                 }
1684                                         } else {
1685                                                 unreachable!();
1686                                         }
1687                                 } else {
1688                                         for forward_info in pending_forwards.drain(..) {
1689                                                 match forward_info {
1690                                                         HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info: PendingHTLCInfo {
1691                                                                         routing: PendingHTLCRouting::Receive { payment_data, incoming_cltv_expiry },
1692                                                                         incoming_shared_secret, payment_hash, amt_to_forward, .. }, } => {
1693                                                                 let prev_hop = HTLCPreviousHopData {
1694                                                                         short_channel_id: prev_short_channel_id,
1695                                                                         htlc_id: prev_htlc_id,
1696                                                                         incoming_packet_shared_secret: incoming_shared_secret,
1697                                                                 };
1698
1699                                                                 let mut total_value = 0;
1700                                                                 let payment_secret_opt =
1701                                                                         if let &Some(ref data) = &payment_data { Some(data.payment_secret.clone()) } else { None };
1702                                                                 let htlcs = channel_state.claimable_htlcs.entry((payment_hash, payment_secret_opt))
1703                                                                         .or_insert(Vec::new());
1704                                                                 htlcs.push(ClaimableHTLC {
1705                                                                         prev_hop,
1706                                                                         value: amt_to_forward,
1707                                                                         payment_data: payment_data.clone(),
1708                                                                         cltv_expiry: incoming_cltv_expiry,
1709                                                                 });
1710                                                                 if let &Some(ref data) = &payment_data {
1711                                                                         for htlc in htlcs.iter() {
1712                                                                                 total_value += htlc.value;
1713                                                                                 if htlc.payment_data.as_ref().unwrap().total_msat != data.total_msat {
1714                                                                                         total_value = msgs::MAX_VALUE_MSAT;
1715                                                                                 }
1716                                                                                 if total_value >= msgs::MAX_VALUE_MSAT { break; }
1717                                                                         }
1718                                                                         if total_value >= msgs::MAX_VALUE_MSAT || total_value > data.total_msat  {
1719                                                                                 for htlc in htlcs.iter() {
1720                                                                                         let mut htlc_msat_height_data = byte_utils::be64_to_array(htlc.value).to_vec();
1721                                                                                         htlc_msat_height_data.extend_from_slice(
1722                                                                                                 &byte_utils::be32_to_array(
1723                                                                                                         self.latest_block_height.load(Ordering::Acquire)
1724                                                                                                                 as u32,
1725                                                                                                 ),
1726                                                                                         );
1727                                                                                         failed_forwards.push((HTLCSource::PreviousHopData(HTLCPreviousHopData {
1728                                                                                                         short_channel_id: htlc.prev_hop.short_channel_id,
1729                                                                                                         htlc_id: htlc.prev_hop.htlc_id,
1730                                                                                                         incoming_packet_shared_secret: htlc.prev_hop.incoming_packet_shared_secret,
1731                                                                                                 }), payment_hash,
1732                                                                                                 HTLCFailReason::Reason { failure_code: 0x4000 | 15, data: htlc_msat_height_data }
1733                                                                                         ));
1734                                                                                 }
1735                                                                         } else if total_value == data.total_msat {
1736                                                                                 new_events.push(events::Event::PaymentReceived {
1737                                                                                         payment_hash: payment_hash,
1738                                                                                         payment_secret: Some(data.payment_secret),
1739                                                                                         amt: total_value,
1740                                                                                 });
1741                                                                         }
1742                                                                 } else {
1743                                                                         new_events.push(events::Event::PaymentReceived {
1744                                                                                 payment_hash: payment_hash,
1745                                                                                 payment_secret: None,
1746                                                                                 amt: amt_to_forward,
1747                                                                         });
1748                                                                 }
1749                                                         },
1750                                                         HTLCForwardInfo::AddHTLC { .. } => {
1751                                                                 panic!("short_channel_id == 0 should imply any pending_forward entries are of type Receive");
1752                                                         },
1753                                                         HTLCForwardInfo::FailHTLC { .. } => {
1754                                                                 panic!("Got pending fail of our own HTLC");
1755                                                         }
1756                                                 }
1757                                         }
1758                                 }
1759                         }
1760                 }
1761
1762                 for (htlc_source, payment_hash, failure_reason) in failed_forwards.drain(..) {
1763                         self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), htlc_source, &payment_hash, failure_reason);
1764                 }
1765
1766                 for (their_node_id, err) in handle_errors.drain(..) {
1767                         let _ = handle_error!(self, err, their_node_id);
1768                 }
1769
1770                 if new_events.is_empty() { return }
1771                 let mut events = self.pending_events.lock().unwrap();
1772                 events.append(&mut new_events);
1773         }
1774
1775         /// If a peer is disconnected we mark any channels with that peer as 'disabled'.
1776         /// After some time, if channels are still disabled we need to broadcast a ChannelUpdate
1777         /// to inform the network about the uselessness of these channels.
1778         ///
1779         /// This method handles all the details, and must be called roughly once per minute.
1780         pub fn timer_chan_freshness_every_min(&self) {
1781                 let _ = self.total_consistency_lock.read().unwrap();
1782                 let mut channel_state_lock = self.channel_state.lock().unwrap();
1783                 let channel_state = &mut *channel_state_lock;
1784                 for (_, chan) in channel_state.by_id.iter_mut() {
1785                         if chan.is_disabled_staged() && !chan.is_live() {
1786                                 if let Ok(update) = self.get_channel_update(&chan) {
1787                                         channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
1788                                                 msg: update
1789                                         });
1790                                 }
1791                                 chan.to_fresh();
1792                         } else if chan.is_disabled_staged() && chan.is_live() {
1793                                 chan.to_fresh();
1794                         } else if chan.is_disabled_marked() {
1795                                 chan.to_disabled_staged();
1796                         }
1797                 }
1798         }
1799
1800         /// Indicates that the preimage for payment_hash is unknown or the received amount is incorrect
1801         /// after a PaymentReceived event, failing the HTLC back to its origin and freeing resources
1802         /// along the path (including in our own channel on which we received it).
1803         /// Returns false if no payment was found to fail backwards, true if the process of failing the
1804         /// HTLC backwards has been started.
1805         pub fn fail_htlc_backwards(&self, payment_hash: &PaymentHash, payment_secret: &Option<PaymentSecret>) -> bool {
1806                 let _ = self.total_consistency_lock.read().unwrap();
1807
1808                 let mut channel_state = Some(self.channel_state.lock().unwrap());
1809                 let removed_source = channel_state.as_mut().unwrap().claimable_htlcs.remove(&(*payment_hash, *payment_secret));
1810                 if let Some(mut sources) = removed_source {
1811                         for htlc in sources.drain(..) {
1812                                 if channel_state.is_none() { channel_state = Some(self.channel_state.lock().unwrap()); }
1813                                 let mut htlc_msat_height_data = byte_utils::be64_to_array(htlc.value).to_vec();
1814                                 htlc_msat_height_data.extend_from_slice(&byte_utils::be32_to_array(
1815                                         self.latest_block_height.load(Ordering::Acquire) as u32,
1816                                 ));
1817                                 self.fail_htlc_backwards_internal(channel_state.take().unwrap(),
1818                                                 HTLCSource::PreviousHopData(htlc.prev_hop), payment_hash,
1819                                                 HTLCFailReason::Reason { failure_code: 0x4000 | 15, data: htlc_msat_height_data });
1820                         }
1821                         true
1822                 } else { false }
1823         }
1824
1825         /// Fails an HTLC backwards to the sender of it to us.
1826         /// Note that while we take a channel_state lock as input, we do *not* assume consistency here.
1827         /// There are several callsites that do stupid things like loop over a list of payment_hashes
1828         /// to fail and take the channel_state lock for each iteration (as we take ownership and may
1829         /// drop it). In other words, no assumptions are made that entries in claimable_htlcs point to
1830         /// still-available channels.
1831         fn fail_htlc_backwards_internal(&self, mut channel_state_lock: MutexGuard<ChannelHolder<ChanSigner>>, source: HTLCSource, payment_hash: &PaymentHash, onion_error: HTLCFailReason) {
1832                 //TODO: There is a timing attack here where if a node fails an HTLC back to us they can
1833                 //identify whether we sent it or not based on the (I presume) very different runtime
1834                 //between the branches here. We should make this async and move it into the forward HTLCs
1835                 //timer handling.
1836                 match source {
1837                         HTLCSource::OutboundRoute { ref path, .. } => {
1838                                 log_trace!(self.logger, "Failing outbound payment HTLC with payment_hash {}", log_bytes!(payment_hash.0));
1839                                 mem::drop(channel_state_lock);
1840                                 match &onion_error {
1841                                         &HTLCFailReason::LightningError { ref err } => {
1842 #[cfg(test)]
1843                                                 let (channel_update, payment_retryable, onion_error_code, onion_error_data) = onion_utils::process_onion_failure(&self.secp_ctx, &self.logger, &source, err.data.clone());
1844 #[cfg(not(test))]
1845                                                 let (channel_update, payment_retryable, _, _) = onion_utils::process_onion_failure(&self.secp_ctx, &self.logger, &source, err.data.clone());
1846                                                 // TODO: If we decided to blame ourselves (or one of our channels) in
1847                                                 // process_onion_failure we should close that channel as it implies our
1848                                                 // next-hop is needlessly blaming us!
1849                                                 if let Some(update) = channel_update {
1850                                                         self.channel_state.lock().unwrap().pending_msg_events.push(
1851                                                                 events::MessageSendEvent::PaymentFailureNetworkUpdate {
1852                                                                         update,
1853                                                                 }
1854                                                         );
1855                                                 }
1856                                                 self.pending_events.lock().unwrap().push(
1857                                                         events::Event::PaymentFailed {
1858                                                                 payment_hash: payment_hash.clone(),
1859                                                                 rejected_by_dest: !payment_retryable,
1860 #[cfg(test)]
1861                                                                 error_code: onion_error_code,
1862 #[cfg(test)]
1863                                                                 error_data: onion_error_data
1864                                                         }
1865                                                 );
1866                                         },
1867                                         &HTLCFailReason::Reason {
1868 #[cfg(test)]
1869                                                         ref failure_code,
1870 #[cfg(test)]
1871                                                         ref data,
1872                                                         .. } => {
1873                                                 // we get a fail_malformed_htlc from the first hop
1874                                                 // TODO: We'd like to generate a PaymentFailureNetworkUpdate for temporary
1875                                                 // failures here, but that would be insufficient as get_route
1876                                                 // generally ignores its view of our own channels as we provide them via
1877                                                 // ChannelDetails.
1878                                                 // TODO: For non-temporary failures, we really should be closing the
1879                                                 // channel here as we apparently can't relay through them anyway.
1880                                                 self.pending_events.lock().unwrap().push(
1881                                                         events::Event::PaymentFailed {
1882                                                                 payment_hash: payment_hash.clone(),
1883                                                                 rejected_by_dest: path.len() == 1,
1884 #[cfg(test)]
1885                                                                 error_code: Some(*failure_code),
1886 #[cfg(test)]
1887                                                                 error_data: Some(data.clone()),
1888                                                         }
1889                                                 );
1890                                         }
1891                                 }
1892                         },
1893                         HTLCSource::PreviousHopData(HTLCPreviousHopData { short_channel_id, htlc_id, incoming_packet_shared_secret }) => {
1894                                 let err_packet = match onion_error {
1895                                         HTLCFailReason::Reason { failure_code, data } => {
1896                                                 log_trace!(self.logger, "Failing HTLC with payment_hash {} backwards from us with code {}", log_bytes!(payment_hash.0), failure_code);
1897                                                 let packet = onion_utils::build_failure_packet(&incoming_packet_shared_secret, failure_code, &data[..]).encode();
1898                                                 onion_utils::encrypt_failure_packet(&incoming_packet_shared_secret, &packet)
1899                                         },
1900                                         HTLCFailReason::LightningError { err } => {
1901                                                 log_trace!(self.logger, "Failing HTLC with payment_hash {} backwards with pre-built LightningError", log_bytes!(payment_hash.0));
1902                                                 onion_utils::encrypt_failure_packet(&incoming_packet_shared_secret, &err.data)
1903                                         }
1904                                 };
1905
1906                                 let mut forward_event = None;
1907                                 if channel_state_lock.forward_htlcs.is_empty() {
1908                                         forward_event = Some(Duration::from_millis(MIN_HTLC_RELAY_HOLDING_CELL_MILLIS));
1909                                 }
1910                                 match channel_state_lock.forward_htlcs.entry(short_channel_id) {
1911                                         hash_map::Entry::Occupied(mut entry) => {
1912                                                 entry.get_mut().push(HTLCForwardInfo::FailHTLC { htlc_id, err_packet });
1913                                         },
1914                                         hash_map::Entry::Vacant(entry) => {
1915                                                 entry.insert(vec!(HTLCForwardInfo::FailHTLC { htlc_id, err_packet }));
1916                                         }
1917                                 }
1918                                 mem::drop(channel_state_lock);
1919                                 if let Some(time) = forward_event {
1920                                         let mut pending_events = self.pending_events.lock().unwrap();
1921                                         pending_events.push(events::Event::PendingHTLCsForwardable {
1922                                                 time_forwardable: time
1923                                         });
1924                                 }
1925                         },
1926                 }
1927         }
1928
1929         /// Provides a payment preimage in response to a PaymentReceived event, returning true and
1930         /// generating message events for the net layer to claim the payment, if possible. Thus, you
1931         /// should probably kick the net layer to go send messages if this returns true!
1932         ///
1933         /// You must specify the expected amounts for this HTLC, and we will only claim HTLCs
1934         /// available within a few percent of the expected amount. This is critical for several
1935         /// reasons : a) it avoids providing senders with `proof-of-payment` (in the form of the
1936         /// payment_preimage without having provided the full value and b) it avoids certain
1937         /// privacy-breaking recipient-probing attacks which may reveal payment activity to
1938         /// motivated attackers.
1939         ///
1940         /// Note that the privacy concerns in (b) are not relevant in payments with a payment_secret
1941         /// set. Thus, for such payments we will claim any payments which do not under-pay.
1942         ///
1943         /// May panic if called except in response to a PaymentReceived event.
1944         pub fn claim_funds(&self, payment_preimage: PaymentPreimage, payment_secret: &Option<PaymentSecret>, expected_amount: u64) -> bool {
1945                 let payment_hash = PaymentHash(Sha256::hash(&payment_preimage.0).into_inner());
1946
1947                 let _ = self.total_consistency_lock.read().unwrap();
1948
1949                 let mut channel_state = Some(self.channel_state.lock().unwrap());
1950                 let removed_source = channel_state.as_mut().unwrap().claimable_htlcs.remove(&(payment_hash, *payment_secret));
1951                 if let Some(mut sources) = removed_source {
1952                         assert!(!sources.is_empty());
1953
1954                         // If we are claiming an MPP payment, we have to take special care to ensure that each
1955                         // channel exists before claiming all of the payments (inside one lock).
1956                         // Note that channel existance is sufficient as we should always get a monitor update
1957                         // which will take care of the real HTLC claim enforcement.
1958                         //
1959                         // If we find an HTLC which we would need to claim but for which we do not have a
1960                         // channel, we will fail all parts of the MPP payment. While we could wait and see if
1961                         // the sender retries the already-failed path(s), it should be a pretty rare case where
1962                         // we got all the HTLCs and then a channel closed while we were waiting for the user to
1963                         // provide the preimage, so worrying too much about the optimal handling isn't worth
1964                         // it.
1965
1966                         let (is_mpp, mut valid_mpp) = if let &Some(ref data) = &sources[0].payment_data {
1967                                 assert!(payment_secret.is_some());
1968                                 (true, data.total_msat >= expected_amount)
1969                         } else {
1970                                 assert!(payment_secret.is_none());
1971                                 (false, false)
1972                         };
1973
1974                         for htlc in sources.iter() {
1975                                 if !is_mpp || !valid_mpp { break; }
1976                                 if let None = channel_state.as_ref().unwrap().short_to_id.get(&htlc.prev_hop.short_channel_id) {
1977                                         valid_mpp = false;
1978                                 }
1979                         }
1980
1981                         let mut errs = Vec::new();
1982                         let mut claimed_any_htlcs = false;
1983                         for htlc in sources.drain(..) {
1984                                 if channel_state.is_none() { channel_state = Some(self.channel_state.lock().unwrap()); }
1985                                 if (is_mpp && !valid_mpp) || (!is_mpp && (htlc.value < expected_amount || htlc.value > expected_amount * 2)) {
1986                                         let mut htlc_msat_height_data = byte_utils::be64_to_array(htlc.value).to_vec();
1987                                         htlc_msat_height_data.extend_from_slice(&byte_utils::be32_to_array(
1988                                                 self.latest_block_height.load(Ordering::Acquire) as u32,
1989                                         ));
1990                                         self.fail_htlc_backwards_internal(channel_state.take().unwrap(),
1991                                                                          HTLCSource::PreviousHopData(htlc.prev_hop), &payment_hash,
1992                                                                          HTLCFailReason::Reason { failure_code: 0x4000|15, data: htlc_msat_height_data });
1993                                 } else {
1994                                         match self.claim_funds_from_hop(channel_state.as_mut().unwrap(), htlc.prev_hop, payment_preimage) {
1995                                                 Err(Some(e)) => {
1996                                                         if let msgs::ErrorAction::IgnoreError = e.1.err.action {
1997                                                                 // We got a temporary failure updating monitor, but will claim the
1998                                                                 // HTLC when the monitor updating is restored (or on chain).
1999                                                                 log_error!(self.logger, "Temporary failure claiming HTLC, treating as success: {}", e.1.err.err);
2000                                                                 claimed_any_htlcs = true;
2001                                                         } else { errs.push(e); }
2002                                                 },
2003                                                 Err(None) if is_mpp => unreachable!("We already checked for channel existence, we can't fail here!"),
2004                                                 Err(None) => {
2005                                                         log_warn!(self.logger, "Channel we expected to claim an HTLC from was closed.");
2006                                                 },
2007                                                 Ok(()) => claimed_any_htlcs = true,
2008                                         }
2009                                 }
2010                         }
2011
2012                         // Now that we've done the entire above loop in one lock, we can handle any errors
2013                         // which were generated.
2014                         channel_state.take();
2015
2016                         for (their_node_id, err) in errs.drain(..) {
2017                                 let res: Result<(), _> = Err(err);
2018                                 let _ = handle_error!(self, res, their_node_id);
2019                         }
2020
2021                         claimed_any_htlcs
2022                 } else { false }
2023         }
2024
2025         fn claim_funds_from_hop(&self, channel_state_lock: &mut MutexGuard<ChannelHolder<ChanSigner>>, prev_hop: HTLCPreviousHopData, payment_preimage: PaymentPreimage) -> Result<(), Option<(PublicKey, MsgHandleErrInternal)>> {
2026                 //TODO: Delay the claimed_funds relaying just like we do outbound relay!
2027                 let channel_state = &mut **channel_state_lock;
2028                 let chan_id = match channel_state.short_to_id.get(&prev_hop.short_channel_id) {
2029                         Some(chan_id) => chan_id.clone(),
2030                         None => {
2031                                 return Err(None)
2032                         }
2033                 };
2034
2035                 if let hash_map::Entry::Occupied(mut chan) = channel_state.by_id.entry(chan_id) {
2036                         let was_frozen_for_monitor = chan.get().is_awaiting_monitor_update();
2037                         match chan.get_mut().get_update_fulfill_htlc_and_commit(prev_hop.htlc_id, payment_preimage, &self.logger) {
2038                                 Ok((msgs, monitor_option)) => {
2039                                         if let Some(monitor_update) = monitor_option {
2040                                                 if let Err(e) = self.monitor.update_monitor(chan.get().get_funding_txo().unwrap(), monitor_update) {
2041                                                         if was_frozen_for_monitor {
2042                                                                 assert!(msgs.is_none());
2043                                                         } else {
2044                                                                 return Err(Some((chan.get().get_their_node_id(), handle_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::CommitmentFirst, false, msgs.is_some()).unwrap_err())));
2045                                                         }
2046                                                 }
2047                                         }
2048                                         if let Some((msg, commitment_signed)) = msgs {
2049                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
2050                                                         node_id: chan.get().get_their_node_id(),
2051                                                         updates: msgs::CommitmentUpdate {
2052                                                                 update_add_htlcs: Vec::new(),
2053                                                                 update_fulfill_htlcs: vec![msg],
2054                                                                 update_fail_htlcs: Vec::new(),
2055                                                                 update_fail_malformed_htlcs: Vec::new(),
2056                                                                 update_fee: None,
2057                                                                 commitment_signed,
2058                                                         }
2059                                                 });
2060                                         }
2061                                         return Ok(())
2062                                 },
2063                                 Err(e) => {
2064                                         // TODO: Do something with e?
2065                                         // This should only occur if we are claiming an HTLC at the same time as the
2066                                         // HTLC is being failed (eg because a block is being connected and this caused
2067                                         // an HTLC to time out). This should, of course, only occur if the user is the
2068                                         // one doing the claiming (as it being a part of a peer claim would imply we're
2069                                         // about to lose funds) and only if the lock in claim_funds was dropped as a
2070                                         // previous HTLC was failed (thus not for an MPP payment).
2071                                         debug_assert!(false, "This shouldn't be reachable except in absurdly rare cases between monitor updates and HTLC timeouts: {:?}", e);
2072                                         return Err(None)
2073                                 },
2074                         }
2075                 } else { unreachable!(); }
2076         }
2077
2078         fn claim_funds_internal(&self, mut channel_state_lock: MutexGuard<ChannelHolder<ChanSigner>>, source: HTLCSource, payment_preimage: PaymentPreimage) {
2079                 match source {
2080                         HTLCSource::OutboundRoute { .. } => {
2081                                 mem::drop(channel_state_lock);
2082                                 let mut pending_events = self.pending_events.lock().unwrap();
2083                                 pending_events.push(events::Event::PaymentSent {
2084                                         payment_preimage
2085                                 });
2086                         },
2087                         HTLCSource::PreviousHopData(hop_data) => {
2088                                 if let Err((their_node_id, err)) = match self.claim_funds_from_hop(&mut channel_state_lock, hop_data, payment_preimage) {
2089                                         Ok(()) => Ok(()),
2090                                         Err(None) => {
2091                                                 // TODO: There is probably a channel monitor somewhere that needs to
2092                                                 // learn the preimage as the channel already hit the chain and that's
2093                                                 // why it's missing.
2094                                                 Ok(())
2095                                         },
2096                                         Err(Some(res)) => Err(res),
2097                                 } {
2098                                         mem::drop(channel_state_lock);
2099                                         let res: Result<(), _> = Err(err);
2100                                         let _ = handle_error!(self, res, their_node_id);
2101                                 }
2102                         },
2103                 }
2104         }
2105
2106         /// Gets the node_id held by this ChannelManager
2107         pub fn get_our_node_id(&self) -> PublicKey {
2108                 PublicKey::from_secret_key(&self.secp_ctx, &self.our_network_key)
2109         }
2110
2111         /// Restores a single, given channel to normal operation after a
2112         /// ChannelMonitorUpdateErr::TemporaryFailure was returned from a channel monitor update
2113         /// operation.
2114         ///
2115         /// All ChannelMonitor updates up to and including highest_applied_update_id must have been
2116         /// fully committed in every copy of the given channels' ChannelMonitors.
2117         ///
2118         /// Note that there is no effect to calling with a highest_applied_update_id other than the
2119         /// current latest ChannelMonitorUpdate and one call to this function after multiple
2120         /// ChannelMonitorUpdateErr::TemporaryFailures is fine. The highest_applied_update_id field
2121         /// exists largely only to prevent races between this and concurrent update_monitor calls.
2122         ///
2123         /// Thus, the anticipated use is, at a high level:
2124         ///  1) You register a ManyChannelMonitor with this ChannelManager,
2125         ///  2) it stores each update to disk, and begins updating any remote (eg watchtower) copies of
2126         ///     said ChannelMonitors as it can, returning ChannelMonitorUpdateErr::TemporaryFailures
2127         ///     any time it cannot do so instantly,
2128         ///  3) update(s) are applied to each remote copy of a ChannelMonitor,
2129         ///  4) once all remote copies are updated, you call this function with the update_id that
2130         ///     completed, and once it is the latest the Channel will be re-enabled.
2131         pub fn channel_monitor_updated(&self, funding_txo: &OutPoint, highest_applied_update_id: u64) {
2132                 let _ = self.total_consistency_lock.read().unwrap();
2133
2134                 let mut close_results = Vec::new();
2135                 let mut htlc_forwards = Vec::new();
2136                 let mut htlc_failures = Vec::new();
2137                 let mut pending_events = Vec::new();
2138
2139                 {
2140                         let mut channel_lock = self.channel_state.lock().unwrap();
2141                         let channel_state = &mut *channel_lock;
2142                         let short_to_id = &mut channel_state.short_to_id;
2143                         let pending_msg_events = &mut channel_state.pending_msg_events;
2144                         let channel = match channel_state.by_id.get_mut(&funding_txo.to_channel_id()) {
2145                                 Some(chan) => chan,
2146                                 None => return,
2147                         };
2148                         if !channel.is_awaiting_monitor_update() || channel.get_latest_monitor_update_id() != highest_applied_update_id {
2149                                 return;
2150                         }
2151
2152                         let (raa, commitment_update, order, pending_forwards, mut pending_failures, needs_broadcast_safe, funding_locked) = channel.monitor_updating_restored(&self.logger);
2153                         if !pending_forwards.is_empty() {
2154                                 htlc_forwards.push((channel.get_short_channel_id().expect("We can't have pending forwards before funding confirmation"), pending_forwards));
2155                         }
2156                         htlc_failures.append(&mut pending_failures);
2157
2158                         macro_rules! handle_cs { () => {
2159                                 if let Some(update) = commitment_update {
2160                                         pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
2161                                                 node_id: channel.get_their_node_id(),
2162                                                 updates: update,
2163                                         });
2164                                 }
2165                         } }
2166                         macro_rules! handle_raa { () => {
2167                                 if let Some(revoke_and_ack) = raa {
2168                                         pending_msg_events.push(events::MessageSendEvent::SendRevokeAndACK {
2169                                                 node_id: channel.get_their_node_id(),
2170                                                 msg: revoke_and_ack,
2171                                         });
2172                                 }
2173                         } }
2174                         match order {
2175                                 RAACommitmentOrder::CommitmentFirst => {
2176                                         handle_cs!();
2177                                         handle_raa!();
2178                                 },
2179                                 RAACommitmentOrder::RevokeAndACKFirst => {
2180                                         handle_raa!();
2181                                         handle_cs!();
2182                                 },
2183                         }
2184                         if needs_broadcast_safe {
2185                                 pending_events.push(events::Event::FundingBroadcastSafe {
2186                                         funding_txo: channel.get_funding_txo().unwrap(),
2187                                         user_channel_id: channel.get_user_id(),
2188                                 });
2189                         }
2190                         if let Some(msg) = funding_locked {
2191                                 pending_msg_events.push(events::MessageSendEvent::SendFundingLocked {
2192                                         node_id: channel.get_their_node_id(),
2193                                         msg,
2194                                 });
2195                                 if let Some(announcement_sigs) = self.get_announcement_sigs(channel) {
2196                                         pending_msg_events.push(events::MessageSendEvent::SendAnnouncementSignatures {
2197                                                 node_id: channel.get_their_node_id(),
2198                                                 msg: announcement_sigs,
2199                                         });
2200                                 }
2201                                 short_to_id.insert(channel.get_short_channel_id().unwrap(), channel.channel_id());
2202                         }
2203                 }
2204
2205                 self.pending_events.lock().unwrap().append(&mut pending_events);
2206
2207                 for failure in htlc_failures.drain(..) {
2208                         self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), failure.0, &failure.1, failure.2);
2209                 }
2210                 self.forward_htlcs(&mut htlc_forwards[..]);
2211
2212                 for res in close_results.drain(..) {
2213                         self.finish_force_close_channel(res);
2214                 }
2215         }
2216
2217         fn internal_open_channel(&self, their_node_id: &PublicKey, their_features: InitFeatures, msg: &msgs::OpenChannel) -> Result<(), MsgHandleErrInternal> {
2218                 if msg.chain_hash != self.genesis_hash {
2219                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Unknown genesis block hash".to_owned(), msg.temporary_channel_id.clone()));
2220                 }
2221
2222                 let channel = Channel::new_from_req(&self.fee_estimator, &self.keys_manager, their_node_id.clone(), their_features, msg, 0, &self.default_configuration)
2223                         .map_err(|e| MsgHandleErrInternal::from_chan_no_close(e, msg.temporary_channel_id))?;
2224                 let mut channel_state_lock = self.channel_state.lock().unwrap();
2225                 let channel_state = &mut *channel_state_lock;
2226                 match channel_state.by_id.entry(channel.channel_id()) {
2227                         hash_map::Entry::Occupied(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("temporary_channel_id collision!".to_owned(), msg.temporary_channel_id.clone())),
2228                         hash_map::Entry::Vacant(entry) => {
2229                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendAcceptChannel {
2230                                         node_id: their_node_id.clone(),
2231                                         msg: channel.get_accept_channel(),
2232                                 });
2233                                 entry.insert(channel);
2234                         }
2235                 }
2236                 Ok(())
2237         }
2238
2239         fn internal_accept_channel(&self, their_node_id: &PublicKey, their_features: InitFeatures, msg: &msgs::AcceptChannel) -> Result<(), MsgHandleErrInternal> {
2240                 let (value, output_script, user_id) = {
2241                         let mut channel_lock = self.channel_state.lock().unwrap();
2242                         let channel_state = &mut *channel_lock;
2243                         match channel_state.by_id.entry(msg.temporary_channel_id) {
2244                                 hash_map::Entry::Occupied(mut chan) => {
2245                                         if chan.get().get_their_node_id() != *their_node_id {
2246                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.temporary_channel_id));
2247                                         }
2248                                         try_chan_entry!(self, chan.get_mut().accept_channel(&msg, &self.default_configuration, their_features), channel_state, chan);
2249                                         (chan.get().get_value_satoshis(), chan.get().get_funding_redeemscript().to_v0_p2wsh(), chan.get().get_user_id())
2250                                 },
2251                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.temporary_channel_id))
2252                         }
2253                 };
2254                 let mut pending_events = self.pending_events.lock().unwrap();
2255                 pending_events.push(events::Event::FundingGenerationReady {
2256                         temporary_channel_id: msg.temporary_channel_id,
2257                         channel_value_satoshis: value,
2258                         output_script: output_script,
2259                         user_channel_id: user_id,
2260                 });
2261                 Ok(())
2262         }
2263
2264         fn internal_funding_created(&self, their_node_id: &PublicKey, msg: &msgs::FundingCreated) -> Result<(), MsgHandleErrInternal> {
2265                 let ((funding_msg, monitor_update), mut chan) = {
2266                         let mut channel_lock = self.channel_state.lock().unwrap();
2267                         let channel_state = &mut *channel_lock;
2268                         match channel_state.by_id.entry(msg.temporary_channel_id.clone()) {
2269                                 hash_map::Entry::Occupied(mut chan) => {
2270                                         if chan.get().get_their_node_id() != *their_node_id {
2271                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.temporary_channel_id));
2272                                         }
2273                                         (try_chan_entry!(self, chan.get_mut().funding_created(msg, &self.logger), channel_state, chan), chan.remove())
2274                                 },
2275                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.temporary_channel_id))
2276                         }
2277                 };
2278                 // Because we have exclusive ownership of the channel here we can release the channel_state
2279                 // lock before add_monitor
2280                 if let Err(e) = self.monitor.add_monitor(monitor_update.get_funding_txo().0, monitor_update) {
2281                         match e {
2282                                 ChannelMonitorUpdateErr::PermanentFailure => {
2283                                         // Note that we reply with the new channel_id in error messages if we gave up on the
2284                                         // channel, not the temporary_channel_id. This is compatible with ourselves, but the
2285                                         // spec is somewhat ambiguous here. Not a huge deal since we'll send error messages for
2286                                         // any messages referencing a previously-closed channel anyway.
2287                                         return Err(MsgHandleErrInternal::from_finish_shutdown("ChannelMonitor storage failure".to_owned(), funding_msg.channel_id, chan.force_shutdown(true), None));
2288                                 },
2289                                 ChannelMonitorUpdateErr::TemporaryFailure => {
2290                                         // There's no problem signing a counterparty's funding transaction if our monitor
2291                                         // hasn't persisted to disk yet - we can't lose money on a transaction that we haven't
2292                                         // accepted payment from yet. We do, however, need to wait to send our funding_locked
2293                                         // until we have persisted our monitor.
2294                                         chan.monitor_update_failed(false, false, Vec::new(), Vec::new());
2295                                 },
2296                         }
2297                 }
2298                 let mut channel_state_lock = self.channel_state.lock().unwrap();
2299                 let channel_state = &mut *channel_state_lock;
2300                 match channel_state.by_id.entry(funding_msg.channel_id) {
2301                         hash_map::Entry::Occupied(_) => {
2302                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Already had channel with the new channel_id".to_owned(), funding_msg.channel_id))
2303                         },
2304                         hash_map::Entry::Vacant(e) => {
2305                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendFundingSigned {
2306                                         node_id: their_node_id.clone(),
2307                                         msg: funding_msg,
2308                                 });
2309                                 e.insert(chan);
2310                         }
2311                 }
2312                 Ok(())
2313         }
2314
2315         fn internal_funding_signed(&self, their_node_id: &PublicKey, msg: &msgs::FundingSigned) -> Result<(), MsgHandleErrInternal> {
2316                 let (funding_txo, user_id) = {
2317                         let mut channel_lock = self.channel_state.lock().unwrap();
2318                         let channel_state = &mut *channel_lock;
2319                         match channel_state.by_id.entry(msg.channel_id) {
2320                                 hash_map::Entry::Occupied(mut chan) => {
2321                                         if chan.get().get_their_node_id() != *their_node_id {
2322                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
2323                                         }
2324                                         let monitor = match chan.get_mut().funding_signed(&msg, &self.logger) {
2325                                                 Ok(update) => update,
2326                                                 Err(e) => try_chan_entry!(self, Err(e), channel_state, chan),
2327                                         };
2328                                         if let Err(e) = self.monitor.add_monitor(chan.get().get_funding_txo().unwrap(), monitor) {
2329                                                 return_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::RevokeAndACKFirst, false, false);
2330                                         }
2331                                         (chan.get().get_funding_txo().unwrap(), chan.get().get_user_id())
2332                                 },
2333                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
2334                         }
2335                 };
2336                 let mut pending_events = self.pending_events.lock().unwrap();
2337                 pending_events.push(events::Event::FundingBroadcastSafe {
2338                         funding_txo: funding_txo,
2339                         user_channel_id: user_id,
2340                 });
2341                 Ok(())
2342         }
2343
2344         fn internal_funding_locked(&self, their_node_id: &PublicKey, msg: &msgs::FundingLocked) -> Result<(), MsgHandleErrInternal> {
2345                 let mut channel_state_lock = self.channel_state.lock().unwrap();
2346                 let channel_state = &mut *channel_state_lock;
2347                 match channel_state.by_id.entry(msg.channel_id) {
2348                         hash_map::Entry::Occupied(mut chan) => {
2349                                 if chan.get().get_their_node_id() != *their_node_id {
2350                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
2351                                 }
2352                                 try_chan_entry!(self, chan.get_mut().funding_locked(&msg), channel_state, chan);
2353                                 if let Some(announcement_sigs) = self.get_announcement_sigs(chan.get()) {
2354                                         log_trace!(self.logger, "Sending announcement_signatures for {} in response to funding_locked", log_bytes!(chan.get().channel_id()));
2355                                         // If we see locking block before receiving remote funding_locked, we broadcast our
2356                                         // announcement_sigs at remote funding_locked reception. If we receive remote
2357                                         // funding_locked before seeing locking block, we broadcast our announcement_sigs at locking
2358                                         // block connection. We should guanrantee to broadcast announcement_sigs to our peer whatever
2359                                         // the order of the events but our peer may not receive it due to disconnection. The specs
2360                                         // lacking an acknowledgement for announcement_sigs we may have to re-send them at peer
2361                                         // connection in the future if simultaneous misses by both peers due to network/hardware
2362                                         // failures is an issue. Note, to achieve its goal, only one of the announcement_sigs needs
2363                                         // to be received, from then sigs are going to be flood to the whole network.
2364                                         channel_state.pending_msg_events.push(events::MessageSendEvent::SendAnnouncementSignatures {
2365                                                 node_id: their_node_id.clone(),
2366                                                 msg: announcement_sigs,
2367                                         });
2368                                 }
2369                                 Ok(())
2370                         },
2371                         hash_map::Entry::Vacant(_) => Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
2372                 }
2373         }
2374
2375         fn internal_shutdown(&self, their_node_id: &PublicKey, msg: &msgs::Shutdown) -> Result<(), MsgHandleErrInternal> {
2376                 let (mut dropped_htlcs, chan_option) = {
2377                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2378                         let channel_state = &mut *channel_state_lock;
2379
2380                         match channel_state.by_id.entry(msg.channel_id.clone()) {
2381                                 hash_map::Entry::Occupied(mut chan_entry) => {
2382                                         if chan_entry.get().get_their_node_id() != *their_node_id {
2383                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
2384                                         }
2385                                         let (shutdown, closing_signed, dropped_htlcs) = try_chan_entry!(self, chan_entry.get_mut().shutdown(&self.fee_estimator, &msg), channel_state, chan_entry);
2386                                         if let Some(msg) = shutdown {
2387                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendShutdown {
2388                                                         node_id: their_node_id.clone(),
2389                                                         msg,
2390                                                 });
2391                                         }
2392                                         if let Some(msg) = closing_signed {
2393                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendClosingSigned {
2394                                                         node_id: their_node_id.clone(),
2395                                                         msg,
2396                                                 });
2397                                         }
2398                                         if chan_entry.get().is_shutdown() {
2399                                                 if let Some(short_id) = chan_entry.get().get_short_channel_id() {
2400                                                         channel_state.short_to_id.remove(&short_id);
2401                                                 }
2402                                                 (dropped_htlcs, Some(chan_entry.remove_entry().1))
2403                                         } else { (dropped_htlcs, None) }
2404                                 },
2405                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
2406                         }
2407                 };
2408                 for htlc_source in dropped_htlcs.drain(..) {
2409                         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() });
2410                 }
2411                 if let Some(chan) = chan_option {
2412                         if let Ok(update) = self.get_channel_update(&chan) {
2413                                 let mut channel_state = self.channel_state.lock().unwrap();
2414                                 channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
2415                                         msg: update
2416                                 });
2417                         }
2418                 }
2419                 Ok(())
2420         }
2421
2422         fn internal_closing_signed(&self, their_node_id: &PublicKey, msg: &msgs::ClosingSigned) -> Result<(), MsgHandleErrInternal> {
2423                 let (tx, chan_option) = {
2424                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2425                         let channel_state = &mut *channel_state_lock;
2426                         match channel_state.by_id.entry(msg.channel_id.clone()) {
2427                                 hash_map::Entry::Occupied(mut chan_entry) => {
2428                                         if chan_entry.get().get_their_node_id() != *their_node_id {
2429                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
2430                                         }
2431                                         let (closing_signed, tx) = try_chan_entry!(self, chan_entry.get_mut().closing_signed(&self.fee_estimator, &msg), channel_state, chan_entry);
2432                                         if let Some(msg) = closing_signed {
2433                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendClosingSigned {
2434                                                         node_id: their_node_id.clone(),
2435                                                         msg,
2436                                                 });
2437                                         }
2438                                         if tx.is_some() {
2439                                                 // We're done with this channel, we've got a signed closing transaction and
2440                                                 // will send the closing_signed back to the remote peer upon return. This
2441                                                 // also implies there are no pending HTLCs left on the channel, so we can
2442                                                 // fully delete it from tracking (the channel monitor is still around to
2443                                                 // watch for old state broadcasts)!
2444                                                 if let Some(short_id) = chan_entry.get().get_short_channel_id() {
2445                                                         channel_state.short_to_id.remove(&short_id);
2446                                                 }
2447                                                 (tx, Some(chan_entry.remove_entry().1))
2448                                         } else { (tx, None) }
2449                                 },
2450                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
2451                         }
2452                 };
2453                 if let Some(broadcast_tx) = tx {
2454                         log_trace!(self.logger, "Broadcast onchain {}", log_tx!(broadcast_tx));
2455                         self.tx_broadcaster.broadcast_transaction(&broadcast_tx);
2456                 }
2457                 if let Some(chan) = chan_option {
2458                         if let Ok(update) = self.get_channel_update(&chan) {
2459                                 let mut channel_state = self.channel_state.lock().unwrap();
2460                                 channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
2461                                         msg: update
2462                                 });
2463                         }
2464                 }
2465                 Ok(())
2466         }
2467
2468         fn internal_update_add_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateAddHTLC) -> Result<(), MsgHandleErrInternal> {
2469                 //TODO: BOLT 4 points out a specific attack where a peer may re-send an onion packet and
2470                 //determine the state of the payment based on our response/if we forward anything/the time
2471                 //we take to respond. We should take care to avoid allowing such an attack.
2472                 //
2473                 //TODO: There exists a further attack where a node may garble the onion data, forward it to
2474                 //us repeatedly garbled in different ways, and compare our error messages, which are
2475                 //encrypted with the same key. It's not immediately obvious how to usefully exploit that,
2476                 //but we should prevent it anyway.
2477
2478                 let (pending_forward_info, mut channel_state_lock) = self.decode_update_add_htlc_onion(msg);
2479                 let channel_state = &mut *channel_state_lock;
2480
2481                 match channel_state.by_id.entry(msg.channel_id) {
2482                         hash_map::Entry::Occupied(mut chan) => {
2483                                 if chan.get().get_their_node_id() != *their_node_id {
2484                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
2485                                 }
2486
2487                                 let create_pending_htlc_status = |chan: &Channel<ChanSigner>, pending_forward_info: PendingHTLCStatus, error_code: u16| {
2488                                         // Ensure error_code has the UPDATE flag set, since by default we send a
2489                                         // channel update along as part of failing the HTLC.
2490                                         assert!((error_code & 0x1000) != 0);
2491                                         // If the update_add is completely bogus, the call will Err and we will close,
2492                                         // but if we've sent a shutdown and they haven't acknowledged it yet, we just
2493                                         // want to reject the new HTLC and fail it backwards instead of forwarding.
2494                                         match pending_forward_info {
2495                                                 PendingHTLCStatus::Forward(PendingHTLCInfo { ref incoming_shared_secret, .. }) => {
2496                                                         let reason = if let Ok(upd) = self.get_channel_update(chan) {
2497                                                                 onion_utils::build_first_hop_failure_packet(incoming_shared_secret, error_code, &{
2498                                                                         let mut res = Vec::with_capacity(8 + 128);
2499                                                                         // TODO: underspecified, follow https://github.com/lightningnetwork/lightning-rfc/issues/791
2500                                                                         res.extend_from_slice(&byte_utils::be16_to_array(0));
2501                                                                         res.extend_from_slice(&upd.encode_with_len()[..]);
2502                                                                         res
2503                                                                 }[..])
2504                                                         } else {
2505                                                                 // The only case where we'd be unable to
2506                                                                 // successfully get a channel update is if the
2507                                                                 // channel isn't in the fully-funded state yet,
2508                                                                 // implying our counterparty is trying to route
2509                                                                 // payments over the channel back to themselves
2510                                                                 // (cause no one else should know the short_id
2511                                                                 // is a lightning channel yet). We should have
2512                                                                 // no problem just calling this
2513                                                                 // unknown_next_peer (0x4000|10).
2514                                                                 onion_utils::build_first_hop_failure_packet(incoming_shared_secret, 0x4000|10, &[])
2515                                                         };
2516                                                         let msg = msgs::UpdateFailHTLC {
2517                                                                 channel_id: msg.channel_id,
2518                                                                 htlc_id: msg.htlc_id,
2519                                                                 reason
2520                                                         };
2521                                                         PendingHTLCStatus::Fail(HTLCFailureMsg::Relay(msg))
2522                                                 },
2523                                                 _ => pending_forward_info
2524                                         }
2525                                 };
2526                                 try_chan_entry!(self, chan.get_mut().update_add_htlc(&msg, pending_forward_info, create_pending_htlc_status, &self.logger), channel_state, chan);
2527                         },
2528                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
2529                 }
2530                 Ok(())
2531         }
2532
2533         fn internal_update_fulfill_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFulfillHTLC) -> Result<(), MsgHandleErrInternal> {
2534                 let mut channel_lock = self.channel_state.lock().unwrap();
2535                 let htlc_source = {
2536                         let channel_state = &mut *channel_lock;
2537                         match channel_state.by_id.entry(msg.channel_id) {
2538                                 hash_map::Entry::Occupied(mut chan) => {
2539                                         if chan.get().get_their_node_id() != *their_node_id {
2540                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
2541                                         }
2542                                         try_chan_entry!(self, chan.get_mut().update_fulfill_htlc(&msg), channel_state, chan)
2543                                 },
2544                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
2545                         }
2546                 };
2547                 self.claim_funds_internal(channel_lock, htlc_source, msg.payment_preimage.clone());
2548                 Ok(())
2549         }
2550
2551         fn internal_update_fail_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFailHTLC) -> Result<(), MsgHandleErrInternal> {
2552                 let mut channel_lock = self.channel_state.lock().unwrap();
2553                 let channel_state = &mut *channel_lock;
2554                 match channel_state.by_id.entry(msg.channel_id) {
2555                         hash_map::Entry::Occupied(mut chan) => {
2556                                 if chan.get().get_their_node_id() != *their_node_id {
2557                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
2558                                 }
2559                                 try_chan_entry!(self, chan.get_mut().update_fail_htlc(&msg, HTLCFailReason::LightningError { err: msg.reason.clone() }), channel_state, chan);
2560                         },
2561                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
2562                 }
2563                 Ok(())
2564         }
2565
2566         fn internal_update_fail_malformed_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFailMalformedHTLC) -> Result<(), MsgHandleErrInternal> {
2567                 let mut channel_lock = self.channel_state.lock().unwrap();
2568                 let channel_state = &mut *channel_lock;
2569                 match channel_state.by_id.entry(msg.channel_id) {
2570                         hash_map::Entry::Occupied(mut chan) => {
2571                                 if chan.get().get_their_node_id() != *their_node_id {
2572                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
2573                                 }
2574                                 if (msg.failure_code & 0x8000) == 0 {
2575                                         let chan_err: ChannelError = ChannelError::Close("Got update_fail_malformed_htlc with BADONION not set".to_owned());
2576                                         try_chan_entry!(self, Err(chan_err), channel_state, chan);
2577                                 }
2578                                 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);
2579                                 Ok(())
2580                         },
2581                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
2582                 }
2583         }
2584
2585         fn internal_commitment_signed(&self, their_node_id: &PublicKey, msg: &msgs::CommitmentSigned) -> Result<(), MsgHandleErrInternal> {
2586                 let mut channel_state_lock = self.channel_state.lock().unwrap();
2587                 let channel_state = &mut *channel_state_lock;
2588                 match channel_state.by_id.entry(msg.channel_id) {
2589                         hash_map::Entry::Occupied(mut chan) => {
2590                                 if chan.get().get_their_node_id() != *their_node_id {
2591                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
2592                                 }
2593                                 let (revoke_and_ack, commitment_signed, closing_signed, monitor_update) =
2594                                         match chan.get_mut().commitment_signed(&msg, &self.fee_estimator, &self.logger) {
2595                                                 Err((None, e)) => try_chan_entry!(self, Err(e), channel_state, chan),
2596                                                 Err((Some(update), e)) => {
2597                                                         assert!(chan.get().is_awaiting_monitor_update());
2598                                                         let _ = self.monitor.update_monitor(chan.get().get_funding_txo().unwrap(), update);
2599                                                         try_chan_entry!(self, Err(e), channel_state, chan);
2600                                                         unreachable!();
2601                                                 },
2602                                                 Ok(res) => res
2603                                         };
2604                                 if let Err(e) = self.monitor.update_monitor(chan.get().get_funding_txo().unwrap(), monitor_update) {
2605                                         return_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::RevokeAndACKFirst, true, commitment_signed.is_some());
2606                                         //TODO: Rebroadcast closing_signed if present on monitor update restoration
2607                                 }
2608                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendRevokeAndACK {
2609                                         node_id: their_node_id.clone(),
2610                                         msg: revoke_and_ack,
2611                                 });
2612                                 if let Some(msg) = commitment_signed {
2613                                         channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
2614                                                 node_id: their_node_id.clone(),
2615                                                 updates: msgs::CommitmentUpdate {
2616                                                         update_add_htlcs: Vec::new(),
2617                                                         update_fulfill_htlcs: Vec::new(),
2618                                                         update_fail_htlcs: Vec::new(),
2619                                                         update_fail_malformed_htlcs: Vec::new(),
2620                                                         update_fee: None,
2621                                                         commitment_signed: msg,
2622                                                 },
2623                                         });
2624                                 }
2625                                 if let Some(msg) = closing_signed {
2626                                         channel_state.pending_msg_events.push(events::MessageSendEvent::SendClosingSigned {
2627                                                 node_id: their_node_id.clone(),
2628                                                 msg,
2629                                         });
2630                                 }
2631                                 Ok(())
2632                         },
2633                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
2634                 }
2635         }
2636
2637         #[inline]
2638         fn forward_htlcs(&self, per_source_pending_forwards: &mut [(u64, Vec<(PendingHTLCInfo, u64)>)]) {
2639                 for &mut (prev_short_channel_id, ref mut pending_forwards) in per_source_pending_forwards {
2640                         let mut forward_event = None;
2641                         if !pending_forwards.is_empty() {
2642                                 let mut channel_state = self.channel_state.lock().unwrap();
2643                                 if channel_state.forward_htlcs.is_empty() {
2644                                         forward_event = Some(Duration::from_millis(MIN_HTLC_RELAY_HOLDING_CELL_MILLIS))
2645                                 }
2646                                 for (forward_info, prev_htlc_id) in pending_forwards.drain(..) {
2647                                         match channel_state.forward_htlcs.entry(match forward_info.routing {
2648                                                         PendingHTLCRouting::Forward { short_channel_id, .. } => short_channel_id,
2649                                                         PendingHTLCRouting::Receive { .. } => 0,
2650                                         }) {
2651                                                 hash_map::Entry::Occupied(mut entry) => {
2652                                                         entry.get_mut().push(HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info });
2653                                                 },
2654                                                 hash_map::Entry::Vacant(entry) => {
2655                                                         entry.insert(vec!(HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info }));
2656                                                 }
2657                                         }
2658                                 }
2659                         }
2660                         match forward_event {
2661                                 Some(time) => {
2662                                         let mut pending_events = self.pending_events.lock().unwrap();
2663                                         pending_events.push(events::Event::PendingHTLCsForwardable {
2664                                                 time_forwardable: time
2665                                         });
2666                                 }
2667                                 None => {},
2668                         }
2669                 }
2670         }
2671
2672         fn internal_revoke_and_ack(&self, their_node_id: &PublicKey, msg: &msgs::RevokeAndACK) -> Result<(), MsgHandleErrInternal> {
2673                 let (pending_forwards, mut pending_failures, short_channel_id) = {
2674                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2675                         let channel_state = &mut *channel_state_lock;
2676                         match channel_state.by_id.entry(msg.channel_id) {
2677                                 hash_map::Entry::Occupied(mut chan) => {
2678                                         if chan.get().get_their_node_id() != *their_node_id {
2679                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
2680                                         }
2681                                         let was_frozen_for_monitor = chan.get().is_awaiting_monitor_update();
2682                                         let (commitment_update, pending_forwards, pending_failures, closing_signed, monitor_update) =
2683                                                 try_chan_entry!(self, chan.get_mut().revoke_and_ack(&msg, &self.fee_estimator, &self.logger), channel_state, chan);
2684                                         if let Err(e) = self.monitor.update_monitor(chan.get().get_funding_txo().unwrap(), monitor_update) {
2685                                                 if was_frozen_for_monitor {
2686                                                         assert!(commitment_update.is_none() && closing_signed.is_none() && pending_forwards.is_empty() && pending_failures.is_empty());
2687                                                         return Err(MsgHandleErrInternal::ignore_no_close("Previous monitor update failure prevented responses to RAA".to_owned()));
2688                                                 } else {
2689                                                         return_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::CommitmentFirst, false, commitment_update.is_some(), pending_forwards, pending_failures);
2690                                                 }
2691                                         }
2692                                         if let Some(updates) = commitment_update {
2693                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
2694                                                         node_id: their_node_id.clone(),
2695                                                         updates,
2696                                                 });
2697                                         }
2698                                         if let Some(msg) = closing_signed {
2699                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendClosingSigned {
2700                                                         node_id: their_node_id.clone(),
2701                                                         msg,
2702                                                 });
2703                                         }
2704                                         (pending_forwards, pending_failures, chan.get().get_short_channel_id().expect("RAA should only work on a short-id-available channel"))
2705                                 },
2706                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
2707                         }
2708                 };
2709                 for failure in pending_failures.drain(..) {
2710                         self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), failure.0, &failure.1, failure.2);
2711                 }
2712                 self.forward_htlcs(&mut [(short_channel_id, pending_forwards)]);
2713
2714                 Ok(())
2715         }
2716
2717         fn internal_update_fee(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFee) -> Result<(), MsgHandleErrInternal> {
2718                 let mut channel_lock = self.channel_state.lock().unwrap();
2719                 let channel_state = &mut *channel_lock;
2720                 match channel_state.by_id.entry(msg.channel_id) {
2721                         hash_map::Entry::Occupied(mut chan) => {
2722                                 if chan.get().get_their_node_id() != *their_node_id {
2723                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
2724                                 }
2725                                 try_chan_entry!(self, chan.get_mut().update_fee(&self.fee_estimator, &msg), channel_state, chan);
2726                         },
2727                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
2728                 }
2729                 Ok(())
2730         }
2731
2732         fn internal_announcement_signatures(&self, their_node_id: &PublicKey, msg: &msgs::AnnouncementSignatures) -> Result<(), MsgHandleErrInternal> {
2733                 let mut channel_state_lock = self.channel_state.lock().unwrap();
2734                 let channel_state = &mut *channel_state_lock;
2735
2736                 match channel_state.by_id.entry(msg.channel_id) {
2737                         hash_map::Entry::Occupied(mut chan) => {
2738                                 if chan.get().get_their_node_id() != *their_node_id {
2739                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
2740                                 }
2741                                 if !chan.get().is_usable() {
2742                                         return Err(MsgHandleErrInternal::from_no_close(LightningError{err: "Got an announcement_signatures before we were ready for it".to_owned(), action: msgs::ErrorAction::IgnoreError}));
2743                                 }
2744
2745                                 let our_node_id = self.get_our_node_id();
2746                                 let (announcement, our_bitcoin_sig) =
2747                                         try_chan_entry!(self, chan.get_mut().get_channel_announcement(our_node_id.clone(), self.genesis_hash.clone()), channel_state, chan);
2748
2749                                 let were_node_one = announcement.node_id_1 == our_node_id;
2750                                 let msghash = hash_to_message!(&Sha256dHash::hash(&announcement.encode()[..])[..]);
2751                                 {
2752                                         let their_node_key = if were_node_one { &announcement.node_id_2 } else { &announcement.node_id_1 };
2753                                         let their_bitcoin_key = if were_node_one { &announcement.bitcoin_key_2 } else { &announcement.bitcoin_key_1 };
2754                                         match (self.secp_ctx.verify(&msghash, &msg.node_signature, their_node_key),
2755                                                    self.secp_ctx.verify(&msghash, &msg.bitcoin_signature, their_bitcoin_key)) {
2756                                                 (Err(e), _) => {
2757                                                         let chan_err: ChannelError = ChannelError::Close(format!("Bad announcement_signatures. Failed to verify node_signature: {:?}. Maybe using different node_secret for transport and routing msg? UnsignedChannelAnnouncement used for verification is {:?}. their_node_key is {:?}", e, &announcement, their_node_key));
2758                                                         try_chan_entry!(self, Err(chan_err), channel_state, chan);
2759                                                 },
2760                                                 (_, Err(e)) => {
2761                                                         let chan_err: ChannelError = ChannelError::Close(format!("Bad announcement_signatures. Failed to verify bitcoin_signature: {:?}. UnsignedChannelAnnouncement used for verification is {:?}. their_bitcoin_key is ({:?})", e, &announcement, their_bitcoin_key));
2762                                                         try_chan_entry!(self, Err(chan_err), channel_state, chan);
2763                                                 },
2764                                                 _ => {}
2765                                         }
2766                                 }
2767
2768                                 let our_node_sig = self.secp_ctx.sign(&msghash, &self.our_network_key);
2769
2770                                 channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelAnnouncement {
2771                                         msg: msgs::ChannelAnnouncement {
2772                                                 node_signature_1: if were_node_one { our_node_sig } else { msg.node_signature },
2773                                                 node_signature_2: if were_node_one { msg.node_signature } else { our_node_sig },
2774                                                 bitcoin_signature_1: if were_node_one { our_bitcoin_sig } else { msg.bitcoin_signature },
2775                                                 bitcoin_signature_2: if were_node_one { msg.bitcoin_signature } else { our_bitcoin_sig },
2776                                                 contents: announcement,
2777                                         },
2778                                         update_msg: self.get_channel_update(chan.get()).unwrap(), // can only fail if we're not in a ready state
2779                                 });
2780                         },
2781                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
2782                 }
2783                 Ok(())
2784         }
2785
2786         fn internal_channel_reestablish(&self, their_node_id: &PublicKey, msg: &msgs::ChannelReestablish) -> Result<(), MsgHandleErrInternal> {
2787                 let mut channel_state_lock = self.channel_state.lock().unwrap();
2788                 let channel_state = &mut *channel_state_lock;
2789
2790                 match channel_state.by_id.entry(msg.channel_id) {
2791                         hash_map::Entry::Occupied(mut chan) => {
2792                                 if chan.get().get_their_node_id() != *their_node_id {
2793                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
2794                                 }
2795                                 let (funding_locked, revoke_and_ack, commitment_update, monitor_update_opt, mut order, shutdown) =
2796                                         try_chan_entry!(self, chan.get_mut().channel_reestablish(msg, &self.logger), channel_state, chan);
2797                                 if let Some(monitor_update) = monitor_update_opt {
2798                                         if let Err(e) = self.monitor.update_monitor(chan.get().get_funding_txo().unwrap(), monitor_update) {
2799                                                 // channel_reestablish doesn't guarantee the order it returns is sensical
2800                                                 // for the messages it returns, but if we're setting what messages to
2801                                                 // re-transmit on monitor update success, we need to make sure it is sane.
2802                                                 if revoke_and_ack.is_none() {
2803                                                         order = RAACommitmentOrder::CommitmentFirst;
2804                                                 }
2805                                                 if commitment_update.is_none() {
2806                                                         order = RAACommitmentOrder::RevokeAndACKFirst;
2807                                                 }
2808                                                 return_monitor_err!(self, e, channel_state, chan, order, revoke_and_ack.is_some(), commitment_update.is_some());
2809                                                 //TODO: Resend the funding_locked if needed once we get the monitor running again
2810                                         }
2811                                 }
2812                                 if let Some(msg) = funding_locked {
2813                                         channel_state.pending_msg_events.push(events::MessageSendEvent::SendFundingLocked {
2814                                                 node_id: their_node_id.clone(),
2815                                                 msg
2816                                         });
2817                                 }
2818                                 macro_rules! send_raa { () => {
2819                                         if let Some(msg) = revoke_and_ack {
2820                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendRevokeAndACK {
2821                                                         node_id: their_node_id.clone(),
2822                                                         msg
2823                                                 });
2824                                         }
2825                                 } }
2826                                 macro_rules! send_cu { () => {
2827                                         if let Some(updates) = commitment_update {
2828                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
2829                                                         node_id: their_node_id.clone(),
2830                                                         updates
2831                                                 });
2832                                         }
2833                                 } }
2834                                 match order {
2835                                         RAACommitmentOrder::RevokeAndACKFirst => {
2836                                                 send_raa!();
2837                                                 send_cu!();
2838                                         },
2839                                         RAACommitmentOrder::CommitmentFirst => {
2840                                                 send_cu!();
2841                                                 send_raa!();
2842                                         },
2843                                 }
2844                                 if let Some(msg) = shutdown {
2845                                         channel_state.pending_msg_events.push(events::MessageSendEvent::SendShutdown {
2846                                                 node_id: their_node_id.clone(),
2847                                                 msg,
2848                                         });
2849                                 }
2850                                 Ok(())
2851                         },
2852                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
2853                 }
2854         }
2855
2856         /// Begin Update fee process. Allowed only on an outbound channel.
2857         /// If successful, will generate a UpdateHTLCs event, so you should probably poll
2858         /// PeerManager::process_events afterwards.
2859         /// Note: This API is likely to change!
2860         #[doc(hidden)]
2861         pub fn update_fee(&self, channel_id: [u8;32], feerate_per_kw: u32) -> Result<(), APIError> {
2862                 let _ = self.total_consistency_lock.read().unwrap();
2863                 let their_node_id;
2864                 let err: Result<(), _> = loop {
2865                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2866                         let channel_state = &mut *channel_state_lock;
2867
2868                         match channel_state.by_id.entry(channel_id) {
2869                                 hash_map::Entry::Vacant(_) => return Err(APIError::APIMisuseError{err: format!("Failed to find corresponding channel for id {}", channel_id.to_hex())}),
2870                                 hash_map::Entry::Occupied(mut chan) => {
2871                                         if !chan.get().is_outbound() {
2872                                                 return Err(APIError::APIMisuseError{err: "update_fee cannot be sent for an inbound channel".to_owned()});
2873                                         }
2874                                         if chan.get().is_awaiting_monitor_update() {
2875                                                 return Err(APIError::MonitorUpdateFailed);
2876                                         }
2877                                         if !chan.get().is_live() {
2878                                                 return Err(APIError::ChannelUnavailable{err: "Channel is either not yet fully established or peer is currently disconnected".to_owned()});
2879                                         }
2880                                         their_node_id = chan.get().get_their_node_id();
2881                                         if let Some((update_fee, commitment_signed, monitor_update)) =
2882                                                         break_chan_entry!(self, chan.get_mut().send_update_fee_and_commit(feerate_per_kw, &self.logger), channel_state, chan)
2883                                         {
2884                                                 if let Err(_e) = self.monitor.update_monitor(chan.get().get_funding_txo().unwrap(), monitor_update) {
2885                                                         unimplemented!();
2886                                                 }
2887                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
2888                                                         node_id: chan.get().get_their_node_id(),
2889                                                         updates: msgs::CommitmentUpdate {
2890                                                                 update_add_htlcs: Vec::new(),
2891                                                                 update_fulfill_htlcs: Vec::new(),
2892                                                                 update_fail_htlcs: Vec::new(),
2893                                                                 update_fail_malformed_htlcs: Vec::new(),
2894                                                                 update_fee: Some(update_fee),
2895                                                                 commitment_signed,
2896                                                         },
2897                                                 });
2898                                         }
2899                                 },
2900                         }
2901                         return Ok(())
2902                 };
2903
2904                 match handle_error!(self, err, their_node_id) {
2905                         Ok(_) => unreachable!(),
2906                         Err(e) => { Err(APIError::APIMisuseError { err: e.err })}
2907                 }
2908         }
2909 }
2910
2911 impl<ChanSigner: ChannelKeys, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> events::MessageSendEventsProvider for ChannelManager<ChanSigner, M, T, K, F, L>
2912         where M::Target: ManyChannelMonitor<Keys=ChanSigner>,
2913         T::Target: BroadcasterInterface,
2914         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
2915         F::Target: FeeEstimator,
2916                                 L::Target: Logger,
2917 {
2918         fn get_and_clear_pending_msg_events(&self) -> Vec<events::MessageSendEvent> {
2919                 // TODO: Event release to users and serialization is currently race-y: it's very easy for a
2920                 // user to serialize a ChannelManager with pending events in it and lose those events on
2921                 // restart. This is doubly true for the fail/fulfill-backs from monitor events!
2922                 {
2923                         //TODO: This behavior should be documented.
2924                         for htlc_update in self.monitor.get_and_clear_pending_htlcs_updated() {
2925                                 if let Some(preimage) = htlc_update.payment_preimage {
2926                                         log_trace!(self.logger, "Claiming HTLC with preimage {} from our monitor", log_bytes!(preimage.0));
2927                                         self.claim_funds_internal(self.channel_state.lock().unwrap(), htlc_update.source, preimage);
2928                                 } else {
2929                                         log_trace!(self.logger, "Failing HTLC with hash {} from our monitor", log_bytes!(htlc_update.payment_hash.0));
2930                                         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() });
2931                                 }
2932                         }
2933                 }
2934
2935                 let mut ret = Vec::new();
2936                 let mut channel_state = self.channel_state.lock().unwrap();
2937                 mem::swap(&mut ret, &mut channel_state.pending_msg_events);
2938                 ret
2939         }
2940 }
2941
2942 impl<ChanSigner: ChannelKeys, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> events::EventsProvider for ChannelManager<ChanSigner, M, T, K, F, L>
2943         where M::Target: ManyChannelMonitor<Keys=ChanSigner>,
2944         T::Target: BroadcasterInterface,
2945         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
2946         F::Target: FeeEstimator,
2947                                 L::Target: Logger,
2948 {
2949         fn get_and_clear_pending_events(&self) -> Vec<events::Event> {
2950                 // TODO: Event release to users and serialization is currently race-y: it's very easy for a
2951                 // user to serialize a ChannelManager with pending events in it and lose those events on
2952                 // restart. This is doubly true for the fail/fulfill-backs from monitor events!
2953                 {
2954                         //TODO: This behavior should be documented.
2955                         for htlc_update in self.monitor.get_and_clear_pending_htlcs_updated() {
2956                                 if let Some(preimage) = htlc_update.payment_preimage {
2957                                         log_trace!(self.logger, "Claiming HTLC with preimage {} from our monitor", log_bytes!(preimage.0));
2958                                         self.claim_funds_internal(self.channel_state.lock().unwrap(), htlc_update.source, preimage);
2959                                 } else {
2960                                         log_trace!(self.logger, "Failing HTLC with hash {} from our monitor", log_bytes!(htlc_update.payment_hash.0));
2961                                         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() });
2962                                 }
2963                         }
2964                 }
2965
2966                 let mut ret = Vec::new();
2967                 let mut pending_events = self.pending_events.lock().unwrap();
2968                 mem::swap(&mut ret, &mut *pending_events);
2969                 ret
2970         }
2971 }
2972
2973 impl<ChanSigner: ChannelKeys, M: Deref + Sync + Send, T: Deref + Sync + Send, K: Deref + Sync + Send, F: Deref + Sync + Send, L: Deref + Sync + Send>
2974         ChainListener for ChannelManager<ChanSigner, M, T, K, F, L>
2975         where M::Target: ManyChannelMonitor<Keys=ChanSigner>,
2976         T::Target: BroadcasterInterface,
2977         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
2978         F::Target: FeeEstimator,
2979                                 L::Target: Logger,
2980 {
2981         fn block_connected(&self, header: &BlockHeader, height: u32, txn_matched: &[&Transaction], indexes_of_txn_matched: &[usize]) {
2982                 let header_hash = header.bitcoin_hash();
2983                 log_trace!(self.logger, "Block {} at height {} connected with {} txn matched", header_hash, height, txn_matched.len());
2984                 let _ = self.total_consistency_lock.read().unwrap();
2985                 let mut failed_channels = Vec::new();
2986                 let mut timed_out_htlcs = Vec::new();
2987                 {
2988                         let mut channel_lock = self.channel_state.lock().unwrap();
2989                         let channel_state = &mut *channel_lock;
2990                         let short_to_id = &mut channel_state.short_to_id;
2991                         let pending_msg_events = &mut channel_state.pending_msg_events;
2992                         channel_state.by_id.retain(|_, channel| {
2993                                 let res = channel.block_connected(header, height, txn_matched, indexes_of_txn_matched);
2994                                 if let Ok((chan_res, mut timed_out_pending_htlcs)) = res {
2995                                         for (source, payment_hash) in timed_out_pending_htlcs.drain(..) {
2996                                                 let chan_update = self.get_channel_update(&channel).map(|u| u.encode_with_len()).unwrap(); // Cannot add/recv HTLCs before we have a short_id so unwrap is safe
2997                                                 timed_out_htlcs.push((source, payment_hash,  HTLCFailReason::Reason {
2998                                                         failure_code: 0x1000 | 14, // expiry_too_soon, or at least it is now
2999                                                         data: chan_update,
3000                                                 }));
3001                                         }
3002                                         if let Some(funding_locked) = chan_res {
3003                                                 pending_msg_events.push(events::MessageSendEvent::SendFundingLocked {
3004                                                         node_id: channel.get_their_node_id(),
3005                                                         msg: funding_locked,
3006                                                 });
3007                                                 if let Some(announcement_sigs) = self.get_announcement_sigs(channel) {
3008                                                         log_trace!(self.logger, "Sending funding_locked and announcement_signatures for {}", log_bytes!(channel.channel_id()));
3009                                                         pending_msg_events.push(events::MessageSendEvent::SendAnnouncementSignatures {
3010                                                                 node_id: channel.get_their_node_id(),
3011                                                                 msg: announcement_sigs,
3012                                                         });
3013                                                 } else {
3014                                                         log_trace!(self.logger, "Sending funding_locked WITHOUT announcement_signatures for {}", log_bytes!(channel.channel_id()));
3015                                                 }
3016                                                 short_to_id.insert(channel.get_short_channel_id().unwrap(), channel.channel_id());
3017                                         }
3018                                 } else if let Err(e) = res {
3019                                         pending_msg_events.push(events::MessageSendEvent::HandleError {
3020                                                 node_id: channel.get_their_node_id(),
3021                                                 action: msgs::ErrorAction::SendErrorMessage { msg: e },
3022                                         });
3023                                         return false;
3024                                 }
3025                                 if let Some(funding_txo) = channel.get_funding_txo() {
3026                                         for tx in txn_matched {
3027                                                 for inp in tx.input.iter() {
3028                                                         if inp.previous_output == funding_txo.into_bitcoin_outpoint() {
3029                                                                 log_trace!(self.logger, "Detected channel-closing tx {} spending {}:{}, closing channel {}", tx.txid(), inp.previous_output.txid, inp.previous_output.vout, log_bytes!(channel.channel_id()));
3030                                                                 if let Some(short_id) = channel.get_short_channel_id() {
3031                                                                         short_to_id.remove(&short_id);
3032                                                                 }
3033                                                                 // It looks like our counterparty went on-chain. We go ahead and
3034                                                                 // broadcast our latest local state as well here, just in case its
3035                                                                 // some kind of SPV attack, though we expect these to be dropped.
3036                                                                 failed_channels.push(channel.force_shutdown(true));
3037                                                                 if let Ok(update) = self.get_channel_update(&channel) {
3038                                                                         pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
3039                                                                                 msg: update
3040                                                                         });
3041                                                                 }
3042                                                                 return false;
3043                                                         }
3044                                                 }
3045                                         }
3046                                 }
3047                                 if channel.is_funding_initiated() && channel.channel_monitor().would_broadcast_at_height(height, &self.logger) {
3048                                         if let Some(short_id) = channel.get_short_channel_id() {
3049                                                 short_to_id.remove(&short_id);
3050                                         }
3051                                         // If would_broadcast_at_height() is true, the channel_monitor will broadcast
3052                                         // the latest local tx for us, so we should skip that here (it doesn't really
3053                                         // hurt anything, but does make tests a bit simpler).
3054                                         failed_channels.push(channel.force_shutdown(false));
3055                                         if let Ok(update) = self.get_channel_update(&channel) {
3056                                                 pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
3057                                                         msg: update
3058                                                 });
3059                                         }
3060                                         return false;
3061                                 }
3062                                 true
3063                         });
3064
3065                         channel_state.claimable_htlcs.retain(|&(ref payment_hash, _), htlcs| {
3066                                 htlcs.retain(|htlc| {
3067                                         // If height is approaching the number of blocks we think it takes us to get
3068                                         // our commitment transaction confirmed before the HTLC expires, plus the
3069                                         // number of blocks we generally consider it to take to do a commitment update,
3070                                         // just give up on it and fail the HTLC.
3071                                         if height >= htlc.cltv_expiry - HTLC_FAIL_BACK_BUFFER {
3072                                                 let mut htlc_msat_height_data = byte_utils::be64_to_array(htlc.value).to_vec();
3073                                                 htlc_msat_height_data.extend_from_slice(&byte_utils::be32_to_array(height));
3074                                                 timed_out_htlcs.push((HTLCSource::PreviousHopData(htlc.prev_hop.clone()), payment_hash.clone(), HTLCFailReason::Reason {
3075                                                         failure_code: 0x4000 | 15,
3076                                                         data: htlc_msat_height_data
3077                                                 }));
3078                                                 false
3079                                         } else { true }
3080                                 });
3081                                 !htlcs.is_empty() // Only retain this entry if htlcs has at least one entry.
3082                         });
3083                 }
3084                 for failure in failed_channels.drain(..) {
3085                         self.finish_force_close_channel(failure);
3086                 }
3087
3088                 for (source, payment_hash, reason) in timed_out_htlcs.drain(..) {
3089                         self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), source, &payment_hash, reason);
3090                 }
3091                 self.latest_block_height.store(height as usize, Ordering::Release);
3092                 *self.last_block_hash.try_lock().expect("block_(dis)connected must not be called in parallel") = header_hash;
3093                 loop {
3094                         // Update last_node_announcement_serial to be the max of its current value and the
3095                         // block timestamp. This should keep us close to the current time without relying on
3096                         // having an explicit local time source.
3097                         // Just in case we end up in a race, we loop until we either successfully update
3098                         // last_node_announcement_serial or decide we don't need to.
3099                         let old_serial = self.last_node_announcement_serial.load(Ordering::Acquire);
3100                         if old_serial >= header.time as usize { break; }
3101                         if self.last_node_announcement_serial.compare_exchange(old_serial, header.time as usize, Ordering::AcqRel, Ordering::Relaxed).is_ok() {
3102                                 break;
3103                         }
3104                 }
3105         }
3106
3107         /// We force-close the channel without letting our counterparty participate in the shutdown
3108         fn block_disconnected(&self, header: &BlockHeader, _: u32) {
3109                 let _ = self.total_consistency_lock.read().unwrap();
3110                 let mut failed_channels = Vec::new();
3111                 {
3112                         let mut channel_lock = self.channel_state.lock().unwrap();
3113                         let channel_state = &mut *channel_lock;
3114                         let short_to_id = &mut channel_state.short_to_id;
3115                         let pending_msg_events = &mut channel_state.pending_msg_events;
3116                         channel_state.by_id.retain(|_,  v| {
3117                                 if v.block_disconnected(header) {
3118                                         if let Some(short_id) = v.get_short_channel_id() {
3119                                                 short_to_id.remove(&short_id);
3120                                         }
3121                                         failed_channels.push(v.force_shutdown(true));
3122                                         if let Ok(update) = self.get_channel_update(&v) {
3123                                                 pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
3124                                                         msg: update
3125                                                 });
3126                                         }
3127                                         false
3128                                 } else {
3129                                         true
3130                                 }
3131                         });
3132                 }
3133                 for failure in failed_channels.drain(..) {
3134                         self.finish_force_close_channel(failure);
3135                 }
3136                 self.latest_block_height.fetch_sub(1, Ordering::AcqRel);
3137                 *self.last_block_hash.try_lock().expect("block_(dis)connected must not be called in parallel") = header.bitcoin_hash();
3138         }
3139 }
3140
3141 impl<ChanSigner: ChannelKeys, M: Deref + Sync + Send, T: Deref + Sync + Send, K: Deref + Sync + Send, F: Deref + Sync + Send, L: Deref + Sync + Send>
3142         ChannelMessageHandler for ChannelManager<ChanSigner, M, T, K, F, L>
3143         where M::Target: ManyChannelMonitor<Keys=ChanSigner>,
3144         T::Target: BroadcasterInterface,
3145         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
3146         F::Target: FeeEstimator,
3147         L::Target: Logger,
3148 {
3149         fn handle_open_channel(&self, their_node_id: &PublicKey, their_features: InitFeatures, msg: &msgs::OpenChannel) {
3150                 let _ = self.total_consistency_lock.read().unwrap();
3151                 let _ = handle_error!(self, self.internal_open_channel(their_node_id, their_features, msg), *their_node_id);
3152         }
3153
3154         fn handle_accept_channel(&self, their_node_id: &PublicKey, their_features: InitFeatures, msg: &msgs::AcceptChannel) {
3155                 let _ = self.total_consistency_lock.read().unwrap();
3156                 let _ = handle_error!(self, self.internal_accept_channel(their_node_id, their_features, msg), *their_node_id);
3157         }
3158
3159         fn handle_funding_created(&self, their_node_id: &PublicKey, msg: &msgs::FundingCreated) {
3160                 let _ = self.total_consistency_lock.read().unwrap();
3161                 let _ = handle_error!(self, self.internal_funding_created(their_node_id, msg), *their_node_id);
3162         }
3163
3164         fn handle_funding_signed(&self, their_node_id: &PublicKey, msg: &msgs::FundingSigned) {
3165                 let _ = self.total_consistency_lock.read().unwrap();
3166                 let _ = handle_error!(self, self.internal_funding_signed(their_node_id, msg), *their_node_id);
3167         }
3168
3169         fn handle_funding_locked(&self, their_node_id: &PublicKey, msg: &msgs::FundingLocked) {
3170                 let _ = self.total_consistency_lock.read().unwrap();
3171                 let _ = handle_error!(self, self.internal_funding_locked(their_node_id, msg), *their_node_id);
3172         }
3173
3174         fn handle_shutdown(&self, their_node_id: &PublicKey, msg: &msgs::Shutdown) {
3175                 let _ = self.total_consistency_lock.read().unwrap();
3176                 let _ = handle_error!(self, self.internal_shutdown(their_node_id, msg), *their_node_id);
3177         }
3178
3179         fn handle_closing_signed(&self, their_node_id: &PublicKey, msg: &msgs::ClosingSigned) {
3180                 let _ = self.total_consistency_lock.read().unwrap();
3181                 let _ = handle_error!(self, self.internal_closing_signed(their_node_id, msg), *their_node_id);
3182         }
3183
3184         fn handle_update_add_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateAddHTLC) {
3185                 let _ = self.total_consistency_lock.read().unwrap();
3186                 let _ = handle_error!(self, self.internal_update_add_htlc(their_node_id, msg), *their_node_id);
3187         }
3188
3189         fn handle_update_fulfill_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFulfillHTLC) {
3190                 let _ = self.total_consistency_lock.read().unwrap();
3191                 let _ = handle_error!(self, self.internal_update_fulfill_htlc(their_node_id, msg), *their_node_id);
3192         }
3193
3194         fn handle_update_fail_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFailHTLC) {
3195                 let _ = self.total_consistency_lock.read().unwrap();
3196                 let _ = handle_error!(self, self.internal_update_fail_htlc(their_node_id, msg), *their_node_id);
3197         }
3198
3199         fn handle_update_fail_malformed_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFailMalformedHTLC) {
3200                 let _ = self.total_consistency_lock.read().unwrap();
3201                 let _ = handle_error!(self, self.internal_update_fail_malformed_htlc(their_node_id, msg), *their_node_id);
3202         }
3203
3204         fn handle_commitment_signed(&self, their_node_id: &PublicKey, msg: &msgs::CommitmentSigned) {
3205                 let _ = self.total_consistency_lock.read().unwrap();
3206                 let _ = handle_error!(self, self.internal_commitment_signed(their_node_id, msg), *their_node_id);
3207         }
3208
3209         fn handle_revoke_and_ack(&self, their_node_id: &PublicKey, msg: &msgs::RevokeAndACK) {
3210                 let _ = self.total_consistency_lock.read().unwrap();
3211                 let _ = handle_error!(self, self.internal_revoke_and_ack(their_node_id, msg), *their_node_id);
3212         }
3213
3214         fn handle_update_fee(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFee) {
3215                 let _ = self.total_consistency_lock.read().unwrap();
3216                 let _ = handle_error!(self, self.internal_update_fee(their_node_id, msg), *their_node_id);
3217         }
3218
3219         fn handle_announcement_signatures(&self, their_node_id: &PublicKey, msg: &msgs::AnnouncementSignatures) {
3220                 let _ = self.total_consistency_lock.read().unwrap();
3221                 let _ = handle_error!(self, self.internal_announcement_signatures(their_node_id, msg), *their_node_id);
3222         }
3223
3224         fn handle_channel_reestablish(&self, their_node_id: &PublicKey, msg: &msgs::ChannelReestablish) {
3225                 let _ = self.total_consistency_lock.read().unwrap();
3226                 let _ = handle_error!(self, self.internal_channel_reestablish(their_node_id, msg), *their_node_id);
3227         }
3228
3229         fn peer_disconnected(&self, their_node_id: &PublicKey, no_connection_possible: bool) {
3230                 let _ = self.total_consistency_lock.read().unwrap();
3231                 let mut failed_channels = Vec::new();
3232                 let mut failed_payments = Vec::new();
3233                 let mut no_channels_remain = true;
3234                 {
3235                         let mut channel_state_lock = self.channel_state.lock().unwrap();
3236                         let channel_state = &mut *channel_state_lock;
3237                         let short_to_id = &mut channel_state.short_to_id;
3238                         let pending_msg_events = &mut channel_state.pending_msg_events;
3239                         if no_connection_possible {
3240                                 log_debug!(self.logger, "Failing all channels with {} due to no_connection_possible", log_pubkey!(their_node_id));
3241                                 channel_state.by_id.retain(|_, chan| {
3242                                         if chan.get_their_node_id() == *their_node_id {
3243                                                 if let Some(short_id) = chan.get_short_channel_id() {
3244                                                         short_to_id.remove(&short_id);
3245                                                 }
3246                                                 failed_channels.push(chan.force_shutdown(true));
3247                                                 if let Ok(update) = self.get_channel_update(&chan) {
3248                                                         pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
3249                                                                 msg: update
3250                                                         });
3251                                                 }
3252                                                 false
3253                                         } else {
3254                                                 true
3255                                         }
3256                                 });
3257                         } else {
3258                                 log_debug!(self.logger, "Marking channels with {} disconnected and generating channel_updates", log_pubkey!(their_node_id));
3259                                 channel_state.by_id.retain(|_, chan| {
3260                                         if chan.get_their_node_id() == *their_node_id {
3261                                                 let failed_adds = chan.remove_uncommitted_htlcs_and_mark_paused(&self.logger);
3262                                                 chan.to_disabled_marked();
3263                                                 if !failed_adds.is_empty() {
3264                                                         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
3265                                                         failed_payments.push((chan_update, failed_adds));
3266                                                 }
3267                                                 if chan.is_shutdown() {
3268                                                         if let Some(short_id) = chan.get_short_channel_id() {
3269                                                                 short_to_id.remove(&short_id);
3270                                                         }
3271                                                         return false;
3272                                                 } else {
3273                                                         no_channels_remain = false;
3274                                                 }
3275                                         }
3276                                         true
3277                                 })
3278                         }
3279                         pending_msg_events.retain(|msg| {
3280                                 match msg {
3281                                         &events::MessageSendEvent::SendAcceptChannel { ref node_id, .. } => node_id != their_node_id,
3282                                         &events::MessageSendEvent::SendOpenChannel { ref node_id, .. } => node_id != their_node_id,
3283                                         &events::MessageSendEvent::SendFundingCreated { ref node_id, .. } => node_id != their_node_id,
3284                                         &events::MessageSendEvent::SendFundingSigned { ref node_id, .. } => node_id != their_node_id,
3285                                         &events::MessageSendEvent::SendFundingLocked { ref node_id, .. } => node_id != their_node_id,
3286                                         &events::MessageSendEvent::SendAnnouncementSignatures { ref node_id, .. } => node_id != their_node_id,
3287                                         &events::MessageSendEvent::UpdateHTLCs { ref node_id, .. } => node_id != their_node_id,
3288                                         &events::MessageSendEvent::SendRevokeAndACK { ref node_id, .. } => node_id != their_node_id,
3289                                         &events::MessageSendEvent::SendClosingSigned { ref node_id, .. } => node_id != their_node_id,
3290                                         &events::MessageSendEvent::SendShutdown { ref node_id, .. } => node_id != their_node_id,
3291                                         &events::MessageSendEvent::SendChannelReestablish { ref node_id, .. } => node_id != their_node_id,
3292                                         &events::MessageSendEvent::BroadcastChannelAnnouncement { .. } => true,
3293                                         &events::MessageSendEvent::BroadcastNodeAnnouncement { .. } => true,
3294                                         &events::MessageSendEvent::BroadcastChannelUpdate { .. } => true,
3295                                         &events::MessageSendEvent::HandleError { ref node_id, .. } => node_id != their_node_id,
3296                                         &events::MessageSendEvent::PaymentFailureNetworkUpdate { .. } => true,
3297                                 }
3298                         });
3299                 }
3300                 if no_channels_remain {
3301                         self.per_peer_state.write().unwrap().remove(their_node_id);
3302                 }
3303
3304                 for failure in failed_channels.drain(..) {
3305                         self.finish_force_close_channel(failure);
3306                 }
3307                 for (chan_update, mut htlc_sources) in failed_payments {
3308                         for (htlc_source, payment_hash) in htlc_sources.drain(..) {
3309                                 self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), htlc_source, &payment_hash, HTLCFailReason::Reason { failure_code: 0x1000 | 7, data: chan_update.clone() });
3310                         }
3311                 }
3312         }
3313
3314         fn peer_connected(&self, their_node_id: &PublicKey, init_msg: &msgs::Init) {
3315                 log_debug!(self.logger, "Generating channel_reestablish events for {}", log_pubkey!(their_node_id));
3316
3317                 let _ = self.total_consistency_lock.read().unwrap();
3318
3319                 {
3320                         let mut peer_state_lock = self.per_peer_state.write().unwrap();
3321                         match peer_state_lock.entry(their_node_id.clone()) {
3322                                 hash_map::Entry::Vacant(e) => {
3323                                         e.insert(Mutex::new(PeerState {
3324                                                 latest_features: init_msg.features.clone(),
3325                                         }));
3326                                 },
3327                                 hash_map::Entry::Occupied(e) => {
3328                                         e.get().lock().unwrap().latest_features = init_msg.features.clone();
3329                                 },
3330                         }
3331                 }
3332
3333                 let mut channel_state_lock = self.channel_state.lock().unwrap();
3334                 let channel_state = &mut *channel_state_lock;
3335                 let pending_msg_events = &mut channel_state.pending_msg_events;
3336                 channel_state.by_id.retain(|_, chan| {
3337                         if chan.get_their_node_id() == *their_node_id {
3338                                 if !chan.have_received_message() {
3339                                         // If we created this (outbound) channel while we were disconnected from the
3340                                         // peer we probably failed to send the open_channel message, which is now
3341                                         // lost. We can't have had anything pending related to this channel, so we just
3342                                         // drop it.
3343                                         false
3344                                 } else {
3345                                         pending_msg_events.push(events::MessageSendEvent::SendChannelReestablish {
3346                                                 node_id: chan.get_their_node_id(),
3347                                                 msg: chan.get_channel_reestablish(&self.logger),
3348                                         });
3349                                         true
3350                                 }
3351                         } else { true }
3352                 });
3353                 //TODO: Also re-broadcast announcement_signatures
3354         }
3355
3356         fn handle_error(&self, their_node_id: &PublicKey, msg: &msgs::ErrorMessage) {
3357                 let _ = self.total_consistency_lock.read().unwrap();
3358
3359                 if msg.channel_id == [0; 32] {
3360                         for chan in self.list_channels() {
3361                                 if chan.remote_network_id == *their_node_id {
3362                                         self.force_close_channel(&chan.channel_id);
3363                                 }
3364                         }
3365                 } else {
3366                         self.force_close_channel(&msg.channel_id);
3367                 }
3368         }
3369 }
3370
3371 const SERIALIZATION_VERSION: u8 = 1;
3372 const MIN_SERIALIZATION_VERSION: u8 = 1;
3373
3374 impl Writeable for PendingHTLCInfo {
3375         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3376                 match &self.routing {
3377                         &PendingHTLCRouting::Forward { ref onion_packet, ref short_channel_id } => {
3378                                 0u8.write(writer)?;
3379                                 onion_packet.write(writer)?;
3380                                 short_channel_id.write(writer)?;
3381                         },
3382                         &PendingHTLCRouting::Receive { ref payment_data, ref incoming_cltv_expiry } => {
3383                                 1u8.write(writer)?;
3384                                 payment_data.write(writer)?;
3385                                 incoming_cltv_expiry.write(writer)?;
3386                         },
3387                 }
3388                 self.incoming_shared_secret.write(writer)?;
3389                 self.payment_hash.write(writer)?;
3390                 self.amt_to_forward.write(writer)?;
3391                 self.outgoing_cltv_value.write(writer)?;
3392                 Ok(())
3393         }
3394 }
3395
3396 impl Readable for PendingHTLCInfo {
3397         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<PendingHTLCInfo, DecodeError> {
3398                 Ok(PendingHTLCInfo {
3399                         routing: match Readable::read(reader)? {
3400                                 0u8 => PendingHTLCRouting::Forward {
3401                                         onion_packet: Readable::read(reader)?,
3402                                         short_channel_id: Readable::read(reader)?,
3403                                 },
3404                                 1u8 => PendingHTLCRouting::Receive {
3405                                         payment_data: Readable::read(reader)?,
3406                                         incoming_cltv_expiry: Readable::read(reader)?,
3407                                 },
3408                                 _ => return Err(DecodeError::InvalidValue),
3409                         },
3410                         incoming_shared_secret: Readable::read(reader)?,
3411                         payment_hash: Readable::read(reader)?,
3412                         amt_to_forward: Readable::read(reader)?,
3413                         outgoing_cltv_value: Readable::read(reader)?,
3414                 })
3415         }
3416 }
3417
3418 impl Writeable for HTLCFailureMsg {
3419         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3420                 match self {
3421                         &HTLCFailureMsg::Relay(ref fail_msg) => {
3422                                 0u8.write(writer)?;
3423                                 fail_msg.write(writer)?;
3424                         },
3425                         &HTLCFailureMsg::Malformed(ref fail_msg) => {
3426                                 1u8.write(writer)?;
3427                                 fail_msg.write(writer)?;
3428                         }
3429                 }
3430                 Ok(())
3431         }
3432 }
3433
3434 impl Readable for HTLCFailureMsg {
3435         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<HTLCFailureMsg, DecodeError> {
3436                 match <u8 as Readable>::read(reader)? {
3437                         0 => Ok(HTLCFailureMsg::Relay(Readable::read(reader)?)),
3438                         1 => Ok(HTLCFailureMsg::Malformed(Readable::read(reader)?)),
3439                         _ => Err(DecodeError::InvalidValue),
3440                 }
3441         }
3442 }
3443
3444 impl Writeable for PendingHTLCStatus {
3445         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3446                 match self {
3447                         &PendingHTLCStatus::Forward(ref forward_info) => {
3448                                 0u8.write(writer)?;
3449                                 forward_info.write(writer)?;
3450                         },
3451                         &PendingHTLCStatus::Fail(ref fail_msg) => {
3452                                 1u8.write(writer)?;
3453                                 fail_msg.write(writer)?;
3454                         }
3455                 }
3456                 Ok(())
3457         }
3458 }
3459
3460 impl Readable for PendingHTLCStatus {
3461         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<PendingHTLCStatus, DecodeError> {
3462                 match <u8 as Readable>::read(reader)? {
3463                         0 => Ok(PendingHTLCStatus::Forward(Readable::read(reader)?)),
3464                         1 => Ok(PendingHTLCStatus::Fail(Readable::read(reader)?)),
3465                         _ => Err(DecodeError::InvalidValue),
3466                 }
3467         }
3468 }
3469
3470 impl_writeable!(HTLCPreviousHopData, 0, {
3471         short_channel_id,
3472         htlc_id,
3473         incoming_packet_shared_secret
3474 });
3475
3476 impl_writeable!(ClaimableHTLC, 0, {
3477         prev_hop,
3478         value,
3479         payment_data,
3480         cltv_expiry
3481 });
3482
3483 impl Writeable for HTLCSource {
3484         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3485                 match self {
3486                         &HTLCSource::PreviousHopData(ref hop_data) => {
3487                                 0u8.write(writer)?;
3488                                 hop_data.write(writer)?;
3489                         },
3490                         &HTLCSource::OutboundRoute { ref path, ref session_priv, ref first_hop_htlc_msat } => {
3491                                 1u8.write(writer)?;
3492                                 path.write(writer)?;
3493                                 session_priv.write(writer)?;
3494                                 first_hop_htlc_msat.write(writer)?;
3495                         }
3496                 }
3497                 Ok(())
3498         }
3499 }
3500
3501 impl Readable for HTLCSource {
3502         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<HTLCSource, DecodeError> {
3503                 match <u8 as Readable>::read(reader)? {
3504                         0 => Ok(HTLCSource::PreviousHopData(Readable::read(reader)?)),
3505                         1 => Ok(HTLCSource::OutboundRoute {
3506                                 path: Readable::read(reader)?,
3507                                 session_priv: Readable::read(reader)?,
3508                                 first_hop_htlc_msat: Readable::read(reader)?,
3509                         }),
3510                         _ => Err(DecodeError::InvalidValue),
3511                 }
3512         }
3513 }
3514
3515 impl Writeable for HTLCFailReason {
3516         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3517                 match self {
3518                         &HTLCFailReason::LightningError { ref err } => {
3519                                 0u8.write(writer)?;
3520                                 err.write(writer)?;
3521                         },
3522                         &HTLCFailReason::Reason { ref failure_code, ref data } => {
3523                                 1u8.write(writer)?;
3524                                 failure_code.write(writer)?;
3525                                 data.write(writer)?;
3526                         }
3527                 }
3528                 Ok(())
3529         }
3530 }
3531
3532 impl Readable for HTLCFailReason {
3533         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<HTLCFailReason, DecodeError> {
3534                 match <u8 as Readable>::read(reader)? {
3535                         0 => Ok(HTLCFailReason::LightningError { err: Readable::read(reader)? }),
3536                         1 => Ok(HTLCFailReason::Reason {
3537                                 failure_code: Readable::read(reader)?,
3538                                 data: Readable::read(reader)?,
3539                         }),
3540                         _ => Err(DecodeError::InvalidValue),
3541                 }
3542         }
3543 }
3544
3545 impl Writeable for HTLCForwardInfo {
3546         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3547                 match self {
3548                         &HTLCForwardInfo::AddHTLC { ref prev_short_channel_id, ref prev_htlc_id, ref forward_info } => {
3549                                 0u8.write(writer)?;
3550                                 prev_short_channel_id.write(writer)?;
3551                                 prev_htlc_id.write(writer)?;
3552                                 forward_info.write(writer)?;
3553                         },
3554                         &HTLCForwardInfo::FailHTLC { ref htlc_id, ref err_packet } => {
3555                                 1u8.write(writer)?;
3556                                 htlc_id.write(writer)?;
3557                                 err_packet.write(writer)?;
3558                         },
3559                 }
3560                 Ok(())
3561         }
3562 }
3563
3564 impl Readable for HTLCForwardInfo {
3565         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<HTLCForwardInfo, DecodeError> {
3566                 match <u8 as Readable>::read(reader)? {
3567                         0 => Ok(HTLCForwardInfo::AddHTLC {
3568                                 prev_short_channel_id: Readable::read(reader)?,
3569                                 prev_htlc_id: Readable::read(reader)?,
3570                                 forward_info: Readable::read(reader)?,
3571                         }),
3572                         1 => Ok(HTLCForwardInfo::FailHTLC {
3573                                 htlc_id: Readable::read(reader)?,
3574                                 err_packet: Readable::read(reader)?,
3575                         }),
3576                         _ => Err(DecodeError::InvalidValue),
3577                 }
3578         }
3579 }
3580
3581 impl<ChanSigner: ChannelKeys + Writeable, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> Writeable for ChannelManager<ChanSigner, M, T, K, F, L>
3582         where M::Target: ManyChannelMonitor<Keys=ChanSigner>,
3583         T::Target: BroadcasterInterface,
3584         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
3585         F::Target: FeeEstimator,
3586         L::Target: Logger,
3587 {
3588         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3589                 let _ = self.total_consistency_lock.write().unwrap();
3590
3591                 writer.write_all(&[SERIALIZATION_VERSION; 1])?;
3592                 writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
3593
3594                 self.genesis_hash.write(writer)?;
3595                 (self.latest_block_height.load(Ordering::Acquire) as u32).write(writer)?;
3596                 self.last_block_hash.lock().unwrap().write(writer)?;
3597
3598                 let channel_state = self.channel_state.lock().unwrap();
3599                 let mut unfunded_channels = 0;
3600                 for (_, channel) in channel_state.by_id.iter() {
3601                         if !channel.is_funding_initiated() {
3602                                 unfunded_channels += 1;
3603                         }
3604                 }
3605                 ((channel_state.by_id.len() - unfunded_channels) as u64).write(writer)?;
3606                 for (_, channel) in channel_state.by_id.iter() {
3607                         if channel.is_funding_initiated() {
3608                                 channel.write(writer)?;
3609                         }
3610                 }
3611
3612                 (channel_state.forward_htlcs.len() as u64).write(writer)?;
3613                 for (short_channel_id, pending_forwards) in channel_state.forward_htlcs.iter() {
3614                         short_channel_id.write(writer)?;
3615                         (pending_forwards.len() as u64).write(writer)?;
3616                         for forward in pending_forwards {
3617                                 forward.write(writer)?;
3618                         }
3619                 }
3620
3621                 (channel_state.claimable_htlcs.len() as u64).write(writer)?;
3622                 for (payment_hash, previous_hops) in channel_state.claimable_htlcs.iter() {
3623                         payment_hash.write(writer)?;
3624                         (previous_hops.len() as u64).write(writer)?;
3625                         for htlc in previous_hops.iter() {
3626                                 htlc.write(writer)?;
3627                         }
3628                 }
3629
3630                 let per_peer_state = self.per_peer_state.write().unwrap();
3631                 (per_peer_state.len() as u64).write(writer)?;
3632                 for (peer_pubkey, peer_state_mutex) in per_peer_state.iter() {
3633                         peer_pubkey.write(writer)?;
3634                         let peer_state = peer_state_mutex.lock().unwrap();
3635                         peer_state.latest_features.write(writer)?;
3636                 }
3637
3638                 let events = self.pending_events.lock().unwrap();
3639                 (events.len() as u64).write(writer)?;
3640                 for event in events.iter() {
3641                         event.write(writer)?;
3642                 }
3643
3644                 (self.last_node_announcement_serial.load(Ordering::Acquire) as u32).write(writer)?;
3645
3646                 Ok(())
3647         }
3648 }
3649
3650 /// Arguments for the creation of a ChannelManager that are not deserialized.
3651 ///
3652 /// At a high-level, the process for deserializing a ChannelManager and resuming normal operation
3653 /// is:
3654 /// 1) Deserialize all stored ChannelMonitors.
3655 /// 2) Deserialize the ChannelManager by filling in this struct and calling <(Sha256dHash,
3656 ///    ChannelManager)>::read(reader, args).
3657 ///    This may result in closing some Channels if the ChannelMonitor is newer than the stored
3658 ///    ChannelManager state to ensure no loss of funds. Thus, transactions may be broadcasted.
3659 /// 3) Register all relevant ChannelMonitor outpoints with your chain watch mechanism using
3660 ///    ChannelMonitor::get_monitored_outpoints and ChannelMonitor::get_funding_txo().
3661 /// 4) Reconnect blocks on your ChannelMonitors.
3662 /// 5) Move the ChannelMonitors into your local ManyChannelMonitor.
3663 /// 6) Disconnect/connect blocks on the ChannelManager.
3664 /// 7) Register the new ChannelManager with your ChainWatchInterface.
3665 pub struct ChannelManagerReadArgs<'a, ChanSigner: 'a + ChannelKeys, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
3666         where M::Target: ManyChannelMonitor<Keys=ChanSigner>,
3667         T::Target: BroadcasterInterface,
3668         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
3669         F::Target: FeeEstimator,
3670         L::Target: Logger,
3671 {
3672
3673         /// The keys provider which will give us relevant keys. Some keys will be loaded during
3674         /// deserialization.
3675         pub keys_manager: K,
3676
3677         /// The fee_estimator for use in the ChannelManager in the future.
3678         ///
3679         /// No calls to the FeeEstimator will be made during deserialization.
3680         pub fee_estimator: F,
3681         /// The ManyChannelMonitor for use in the ChannelManager in the future.
3682         ///
3683         /// No calls to the ManyChannelMonitor will be made during deserialization. It is assumed that
3684         /// you have deserialized ChannelMonitors separately and will add them to your
3685         /// ManyChannelMonitor after deserializing this ChannelManager.
3686         pub monitor: M,
3687
3688         /// The BroadcasterInterface which will be used in the ChannelManager in the future and may be
3689         /// used to broadcast the latest local commitment transactions of channels which must be
3690         /// force-closed during deserialization.
3691         pub tx_broadcaster: T,
3692         /// The Logger for use in the ChannelManager and which may be used to log information during
3693         /// deserialization.
3694         pub logger: L,
3695         /// Default settings used for new channels. Any existing channels will continue to use the
3696         /// runtime settings which were stored when the ChannelManager was serialized.
3697         pub default_config: UserConfig,
3698
3699         /// A map from channel funding outpoints to ChannelMonitors for those channels (ie
3700         /// value.get_funding_txo() should be the key).
3701         ///
3702         /// If a monitor is inconsistent with the channel state during deserialization the channel will
3703         /// be force-closed using the data in the ChannelMonitor and the channel will be dropped. This
3704         /// is true for missing channels as well. If there is a monitor missing for which we find
3705         /// channel data Err(DecodeError::InvalidValue) will be returned.
3706         ///
3707         /// In such cases the latest local transactions will be sent to the tx_broadcaster included in
3708         /// this struct.
3709         pub channel_monitors: &'a mut HashMap<OutPoint, &'a mut ChannelMonitor<ChanSigner>>,
3710 }
3711
3712 // Implement ReadableArgs for an Arc'd ChannelManager to make it a bit easier to work with the
3713 // SipmleArcChannelManager type:
3714 impl<'a, ChanSigner: ChannelKeys + Readable, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
3715         ReadableArgs<ChannelManagerReadArgs<'a, ChanSigner, M, T, K, F, L>> for (BlockHash, Arc<ChannelManager<ChanSigner, M, T, K, F, L>>)
3716         where M::Target: ManyChannelMonitor<Keys=ChanSigner>,
3717         T::Target: BroadcasterInterface,
3718         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
3719         F::Target: FeeEstimator,
3720         L::Target: Logger,
3721 {
3722         fn read<R: ::std::io::Read>(reader: &mut R, args: ChannelManagerReadArgs<'a, ChanSigner, M, T, K, F, L>) -> Result<Self, DecodeError> {
3723                 let (blockhash, chan_manager) = <(BlockHash, ChannelManager<ChanSigner, M, T, K, F, L>)>::read(reader, args)?;
3724                 Ok((blockhash, Arc::new(chan_manager)))
3725         }
3726 }
3727
3728 impl<'a, ChanSigner: ChannelKeys + Readable, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
3729         ReadableArgs<ChannelManagerReadArgs<'a, ChanSigner, M, T, K, F, L>> for (BlockHash, ChannelManager<ChanSigner, M, T, K, F, L>)
3730         where M::Target: ManyChannelMonitor<Keys=ChanSigner>,
3731         T::Target: BroadcasterInterface,
3732         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
3733         F::Target: FeeEstimator,
3734         L::Target: Logger,
3735 {
3736         fn read<R: ::std::io::Read>(reader: &mut R, args: ChannelManagerReadArgs<'a, ChanSigner, M, T, K, F, L>) -> Result<Self, DecodeError> {
3737                 let _ver: u8 = Readable::read(reader)?;
3738                 let min_ver: u8 = Readable::read(reader)?;
3739                 if min_ver > SERIALIZATION_VERSION {
3740                         return Err(DecodeError::UnknownVersion);
3741                 }
3742
3743                 let genesis_hash: BlockHash = Readable::read(reader)?;
3744                 let latest_block_height: u32 = Readable::read(reader)?;
3745                 let last_block_hash: BlockHash = Readable::read(reader)?;
3746
3747                 let mut failed_htlcs = Vec::new();
3748
3749                 let channel_count: u64 = Readable::read(reader)?;
3750                 let mut funding_txo_set = HashSet::with_capacity(cmp::min(channel_count as usize, 128));
3751                 let mut by_id = HashMap::with_capacity(cmp::min(channel_count as usize, 128));
3752                 let mut short_to_id = HashMap::with_capacity(cmp::min(channel_count as usize, 128));
3753                 for _ in 0..channel_count {
3754                         let mut channel: Channel<ChanSigner> = Readable::read(reader)?;
3755                         if channel.last_block_connected != Default::default() && channel.last_block_connected != last_block_hash {
3756                                 return Err(DecodeError::InvalidValue);
3757                         }
3758
3759                         let funding_txo = channel.get_funding_txo().ok_or(DecodeError::InvalidValue)?;
3760                         funding_txo_set.insert(funding_txo.clone());
3761                         if let Some(ref mut monitor) = args.channel_monitors.get_mut(&funding_txo) {
3762                                 if channel.get_cur_local_commitment_transaction_number() < monitor.get_cur_local_commitment_number() ||
3763                                                 channel.get_revoked_remote_commitment_transaction_number() < monitor.get_min_seen_secret() ||
3764                                                 channel.get_cur_remote_commitment_transaction_number() < monitor.get_cur_remote_commitment_number() ||
3765                                                 channel.get_latest_monitor_update_id() > monitor.get_latest_update_id() {
3766                                         // If the channel is ahead of the monitor, return InvalidValue:
3767                                         return Err(DecodeError::InvalidValue);
3768                                 } else if channel.get_cur_local_commitment_transaction_number() > monitor.get_cur_local_commitment_number() ||
3769                                                 channel.get_revoked_remote_commitment_transaction_number() > monitor.get_min_seen_secret() ||
3770                                                 channel.get_cur_remote_commitment_transaction_number() > monitor.get_cur_remote_commitment_number() ||
3771                                                 channel.get_latest_monitor_update_id() < monitor.get_latest_update_id() {
3772                                         // But if the channel is behind of the monitor, close the channel:
3773                                         let (_, _, mut new_failed_htlcs) = channel.force_shutdown(true);
3774                                         failed_htlcs.append(&mut new_failed_htlcs);
3775                                         monitor.broadcast_latest_local_commitment_txn(&args.tx_broadcaster, &args.logger);
3776                                 } else {
3777                                         if let Some(short_channel_id) = channel.get_short_channel_id() {
3778                                                 short_to_id.insert(short_channel_id, channel.channel_id());
3779                                         }
3780                                         by_id.insert(channel.channel_id(), channel);
3781                                 }
3782                         } else {
3783                                 return Err(DecodeError::InvalidValue);
3784                         }
3785                 }
3786
3787                 for (ref funding_txo, ref mut monitor) in args.channel_monitors.iter_mut() {
3788                         if !funding_txo_set.contains(funding_txo) {
3789                                 monitor.broadcast_latest_local_commitment_txn(&args.tx_broadcaster, &args.logger);
3790                         }
3791                 }
3792
3793                 const MAX_ALLOC_SIZE: usize = 1024 * 64;
3794                 let forward_htlcs_count: u64 = Readable::read(reader)?;
3795                 let mut forward_htlcs = HashMap::with_capacity(cmp::min(forward_htlcs_count as usize, 128));
3796                 for _ in 0..forward_htlcs_count {
3797                         let short_channel_id = Readable::read(reader)?;
3798                         let pending_forwards_count: u64 = Readable::read(reader)?;
3799                         let mut pending_forwards = Vec::with_capacity(cmp::min(pending_forwards_count as usize, MAX_ALLOC_SIZE/mem::size_of::<HTLCForwardInfo>()));
3800                         for _ in 0..pending_forwards_count {
3801                                 pending_forwards.push(Readable::read(reader)?);
3802                         }
3803                         forward_htlcs.insert(short_channel_id, pending_forwards);
3804                 }
3805
3806                 let claimable_htlcs_count: u64 = Readable::read(reader)?;
3807                 let mut claimable_htlcs = HashMap::with_capacity(cmp::min(claimable_htlcs_count as usize, 128));
3808                 for _ in 0..claimable_htlcs_count {
3809                         let payment_hash = Readable::read(reader)?;
3810                         let previous_hops_len: u64 = Readable::read(reader)?;
3811                         let mut previous_hops = Vec::with_capacity(cmp::min(previous_hops_len as usize, MAX_ALLOC_SIZE/mem::size_of::<ClaimableHTLC>()));
3812                         for _ in 0..previous_hops_len {
3813                                 previous_hops.push(Readable::read(reader)?);
3814                         }
3815                         claimable_htlcs.insert(payment_hash, previous_hops);
3816                 }
3817
3818                 let peer_count: u64 = Readable::read(reader)?;
3819                 let mut per_peer_state = HashMap::with_capacity(cmp::min(peer_count as usize, MAX_ALLOC_SIZE/mem::size_of::<(PublicKey, Mutex<PeerState>)>()));
3820                 for _ in 0..peer_count {
3821                         let peer_pubkey = Readable::read(reader)?;
3822                         let peer_state = PeerState {
3823                                 latest_features: Readable::read(reader)?,
3824                         };
3825                         per_peer_state.insert(peer_pubkey, Mutex::new(peer_state));
3826                 }
3827
3828                 let event_count: u64 = Readable::read(reader)?;
3829                 let mut pending_events_read: Vec<events::Event> = Vec::with_capacity(cmp::min(event_count as usize, MAX_ALLOC_SIZE/mem::size_of::<events::Event>()));
3830                 for _ in 0..event_count {
3831                         match MaybeReadable::read(reader)? {
3832                                 Some(event) => pending_events_read.push(event),
3833                                 None => continue,
3834                         }
3835                 }
3836
3837                 let last_node_announcement_serial: u32 = Readable::read(reader)?;
3838
3839                 let channel_manager = ChannelManager {
3840                         genesis_hash,
3841                         fee_estimator: args.fee_estimator,
3842                         monitor: args.monitor,
3843                         tx_broadcaster: args.tx_broadcaster,
3844
3845                         latest_block_height: AtomicUsize::new(latest_block_height as usize),
3846                         last_block_hash: Mutex::new(last_block_hash),
3847                         secp_ctx: Secp256k1::new(),
3848
3849                         channel_state: Mutex::new(ChannelHolder {
3850                                 by_id,
3851                                 short_to_id,
3852                                 forward_htlcs,
3853                                 claimable_htlcs,
3854                                 pending_msg_events: Vec::new(),
3855                         }),
3856                         our_network_key: args.keys_manager.get_node_secret(),
3857
3858                         last_node_announcement_serial: AtomicUsize::new(last_node_announcement_serial as usize),
3859
3860                         per_peer_state: RwLock::new(per_peer_state),
3861
3862                         pending_events: Mutex::new(pending_events_read),
3863                         total_consistency_lock: RwLock::new(()),
3864                         keys_manager: args.keys_manager,
3865                         logger: args.logger,
3866                         default_configuration: args.default_config,
3867                 };
3868
3869                 for htlc_source in failed_htlcs.drain(..) {
3870                         channel_manager.fail_htlc_backwards_internal(channel_manager.channel_state.lock().unwrap(), htlc_source.0, &htlc_source.1, HTLCFailReason::Reason { failure_code: 0x4000 | 8, data: Vec::new() });
3871                 }
3872
3873                 //TODO: Broadcast channel update for closed channels, but only after we've made a
3874                 //connection or two.
3875
3876                 Ok((last_block_hash.clone(), channel_manager))
3877         }
3878 }