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

   1 //! The top-level channel management and payment tracking stuff lives here.
   2 //!
   3 //! The ChannelManager is the main chunk of logic implementing the lightning protocol and is
   4 //! responsible for tracking which channels are open, HTLCs are in flight and reestablishing those
   5 //! upon reconnect to the relevant peer(s).
   6 //!
   7 //! It does not manage routing logic (see ln::router for that) nor does it manage constructing
   8 //! on-chain transactions (it only monitors the chain to watch for any force-closes that might
   9 //! imply it needs to fail HTLCs/payments/channels it manages).
  10
  11 use bitcoin::blockdata::block::BlockHeader;
  12 use bitcoin::blockdata::transaction::Transaction;
  13 use bitcoin::blockdata::constants::genesis_block;
  14 use bitcoin::network::constants::Network;
  15 use bitcoin::util::hash::{BitcoinHash, Sha256dHash};
  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::cmp::fixed_time_eq;
  21
  22 use secp256k1::key::{SecretKey,PublicKey};
  23 use secp256k1::{Secp256k1,Message};
  24 use secp256k1::ecdh::SharedSecret;
  25 use secp256k1;
  26
  27 use chain::chaininterface::{BroadcasterInterface,ChainListener,ChainWatchInterface,FeeEstimator};
  28 use chain::transaction::OutPoint;
  29 use ln::channel::{Channel, ChannelError};
  30 use ln::channelmonitor::{ChannelMonitor, ChannelMonitorUpdateErr, ManyChannelMonitor, CLTV_CLAIM_BUFFER, HTLC_FAIL_TIMEOUT_BLOCKS, HTLC_FAIL_ANTI_REORG_DELAY};
  31 use ln::router::Route;
  32 use ln::msgs;
  33 use ln::onion_utils;
  34 use ln::msgs::{ChannelMessageHandler, DecodeError, HandleError};
  35 use chain::keysinterface::KeysInterface;
  36 use util::config::UserConfig;
  37 use util::{byte_utils, events, rng};
  38 use util::ser::{Readable, ReadableArgs, Writeable, Writer};
  39 use util::chacha20::ChaCha20;
  40 use util::logger::Logger;
  41 use util::errors::APIError;
  42
  43 use std::{cmp, mem};
  44 use std::collections::{HashMap, hash_map, HashSet};
  45 use std::io::Cursor;
  46 use std::sync::{Arc, Mutex, MutexGuard, RwLock};
  47 use std::sync::atomic::{AtomicUsize, Ordering};
  48 use std::time::{Instant,Duration};
  49
  50 // We hold various information about HTLC relay in the HTLC objects in Channel itself:
  51 //
  52 // Upon receipt of an HTLC from a peer, we'll give it a PendingHTLCStatus indicating if it should
  53 // forward the HTLC with information it will give back to us when it does so, or if it should Fail
  54 // the HTLC with the relevant message for the Channel to handle giving to the remote peer.
  55 //
  56 // When a Channel forwards an HTLC to its peer, it will give us back the PendingForwardHTLCInfo
  57 // which we will use to construct an outbound HTLC, with a relevant HTLCSource::PreviousHopData
  58 // filled in to indicate where it came from (which we can use to either fail-backwards or fulfill
  59 // the HTLC backwards along the relevant path).
  60 // Alternatively, we can fill an outbound HTLC with a HTLCSource::OutboundRoute indicating this is
  61 // our payment, which we can use to decode errors or inform the user that the payment was sent.
  62 /// Stores the info we will need to send when we want to forward an HTLC onwards
  63 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
  64 pub(super) struct PendingForwardHTLCInfo {
  65         onion_packet: Option<msgs::OnionPacket>,
  66         incoming_shared_secret: [u8; 32],
  67         payment_hash: PaymentHash,
  68         short_channel_id: u64,
  69         pub(super) amt_to_forward: u64,
  70         pub(super) outgoing_cltv_value: u32,
  71 }
  72
  73 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
  74 pub(super) enum HTLCFailureMsg {
  75         Relay(msgs::UpdateFailHTLC),
  76         Malformed(msgs::UpdateFailMalformedHTLC),
  77 }
  78
  79 /// Stores whether we can't forward an HTLC or relevant forwarding info
  80 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
  81 pub(super) enum PendingHTLCStatus {
  82         Forward(PendingForwardHTLCInfo),
  83         Fail(HTLCFailureMsg),
  84 }
  85
  86 /// Tracks the inbound corresponding to an outbound HTLC
  87 #[derive(Clone, PartialEq)]
  88 pub(super) struct HTLCPreviousHopData {
  89         short_channel_id: u64,
  90         htlc_id: u64,
  91         incoming_packet_shared_secret: [u8; 32],
  92 }
  93
  94 /// Tracks the inbound corresponding to an outbound HTLC
  95 #[derive(Clone, PartialEq)]
  96 pub(super) enum HTLCSource {
  97         PreviousHopData(HTLCPreviousHopData),
  98         OutboundRoute {
  99                 route: Route,
 100                 session_priv: SecretKey,
 101                 /// Technically we can recalculate this from the route, but we cache it here to avoid
 102                 /// doing a double-pass on route when we get a failure back
 103                 first_hop_htlc_msat: u64,
 104         },
 105 }
 106 #[cfg(test)]
 107 impl HTLCSource {
 108         pub fn dummy() -> Self {
 109                 HTLCSource::OutboundRoute {
 110                         route: Route { hops: Vec::new() },
 111                         session_priv: SecretKey::from_slice(&::secp256k1::Secp256k1::without_caps(), &[1; 32]).unwrap(),
 112                         first_hop_htlc_msat: 0,
 113                 }
 114         }
 115 }
 116
 117 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
 118 pub(super) enum HTLCFailReason {
 119         ErrorPacket {
 120                 err: msgs::OnionErrorPacket,
 121         },
 122         Reason {
 123                 failure_code: u16,
 124                 data: Vec<u8>,
 125         }
 126 }
 127
 128 /// payment_hash type, use to cross-lock hop
 129 #[derive(Hash, Copy, Clone, PartialEq, Eq, Debug)]
 130 pub struct PaymentHash(pub [u8;32]);
 131 /// payment_preimage type, use to route payment between hop
 132 #[derive(Hash, Copy, Clone, PartialEq, Eq, Debug)]
 133 pub struct PaymentPreimage(pub [u8;32]);
 134
 135 type ShutdownResult = (Vec<Transaction>, Vec<(HTLCSource, PaymentHash)>);
 136
 137 /// Error type returned across the channel_state mutex boundary. When an Err is generated for a
 138 /// Channel, we generally end up with a ChannelError::Close for which we have to close the channel
 139 /// immediately (ie with no further calls on it made). Thus, this step happens inside a
 140 /// channel_state lock. We then return the set of things that need to be done outside the lock in
 141 /// this struct and call handle_error!() on it.
 142
 143 struct MsgHandleErrInternal {
 144         err: msgs::HandleError,
 145         shutdown_finish: Option<(ShutdownResult, Option<msgs::ChannelUpdate>)>,
 146 }
 147 impl MsgHandleErrInternal {
 148         #[inline]
 149         fn send_err_msg_no_close(err: &'static str, channel_id: [u8; 32]) -> Self {
 150                 Self {
 151                         err: HandleError {
 152                                 err,
 153                                 action: Some(msgs::ErrorAction::SendErrorMessage {
 154                                         msg: msgs::ErrorMessage {
 155                                                 channel_id,
 156                                                 data: err.to_string()
 157                                         },
 158                                 }),
 159                         },
 160                         shutdown_finish: None,
 161                 }
 162         }
 163         #[inline]
 164         fn from_no_close(err: msgs::HandleError) -> Self {
 165                 Self { err, shutdown_finish: None }
 166         }
 167         #[inline]
 168         fn from_finish_shutdown(err: &'static str, channel_id: [u8; 32], shutdown_res: ShutdownResult, channel_update: Option<msgs::ChannelUpdate>) -> Self {
 169                 Self {
 170                         err: HandleError {
 171                                 err,
 172                                 action: Some(msgs::ErrorAction::SendErrorMessage {
 173                                         msg: msgs::ErrorMessage {
 174                                                 channel_id,
 175                                                 data: err.to_string()
 176                                         },
 177                                 }),
 178                         },
 179                         shutdown_finish: Some((shutdown_res, channel_update)),
 180                 }
 181         }
 182         #[inline]
 183         fn from_chan_no_close(err: ChannelError, channel_id: [u8; 32]) -> Self {
 184                 Self {
 185                         err: match err {
 186                                 ChannelError::Ignore(msg) => HandleError {
 187                                         err: msg,
 188                                         action: Some(msgs::ErrorAction::IgnoreError),
 189                                 },
 190                                 ChannelError::Close(msg) => HandleError {
 191                                         err: msg,
 192                                         action: Some(msgs::ErrorAction::SendErrorMessage {
 193                                                 msg: msgs::ErrorMessage {
 194                                                         channel_id,
 195                                                         data: msg.to_string()
 196                                                 },
 197                                         }),
 198                                 },
 199                         },
 200                         shutdown_finish: None,
 201                 }
 202         }
 203 }
 204
 205 /// We hold back HTLCs we intend to relay for a random interval in the range (this, 5*this). This
 206 /// provides some limited amount of privacy. Ideally this would range from somewhere like 1 second
 207 /// to 30 seconds, but people expect lightning to be, you know, kinda fast, sadly. We could
 208 /// probably increase this significantly.
 209 const MIN_HTLC_RELAY_HOLDING_CELL_MILLIS: u32 = 50;
 210
 211 pub(super) enum HTLCForwardInfo {
 212         AddHTLC {
 213                 prev_short_channel_id: u64,
 214                 prev_htlc_id: u64,
 215                 forward_info: PendingForwardHTLCInfo,
 216         },
 217         FailHTLC {
 218                 htlc_id: u64,
 219                 err_packet: msgs::OnionErrorPacket,
 220         },
 221 }
 222
 223 /// For events which result in both a RevokeAndACK and a CommitmentUpdate, by default they should
 224 /// be sent in the order they appear in the return value, however sometimes the order needs to be
 225 /// variable at runtime (eg Channel::channel_reestablish needs to re-send messages in the order
 226 /// they were originally sent). In those cases, this enum is also returned.
 227 #[derive(Clone, PartialEq)]
 228 pub(super) enum RAACommitmentOrder {
 229         /// Send the CommitmentUpdate messages first
 230         CommitmentFirst,
 231         /// Send the RevokeAndACK message first
 232         RevokeAndACKFirst,
 233 }
 234
 235 // Note this is only exposed in cfg(test):
 236 pub(super) struct ChannelHolder {
 237         pub(super) by_id: HashMap<[u8; 32], Channel>,
 238         pub(super) short_to_id: HashMap<u64, [u8; 32]>,
 239         pub(super) next_forward: Instant,
 240         /// short channel id -> forward infos. Key of 0 means payments received
 241         /// Note that while this is held in the same mutex as the channels themselves, no consistency
 242         /// guarantees are made about there existing a channel with the short id here, nor the short
 243         /// ids in the PendingForwardHTLCInfo!
 244         pub(super) forward_htlcs: HashMap<u64, Vec<HTLCForwardInfo>>,
 245         /// Note that while this is held in the same mutex as the channels themselves, no consistency
 246         /// guarantees are made about the channels given here actually existing anymore by the time you
 247         /// go to read them!
 248         pub(super) claimable_htlcs: HashMap<PaymentHash, Vec<HTLCPreviousHopData>>,
 249         /// Messages to send to peers - pushed to in the same lock that they are generated in (except
 250         /// for broadcast messages, where ordering isn't as strict).
 251         pub(super) pending_msg_events: Vec<events::MessageSendEvent>,
 252 }
 253 pub(super) struct MutChannelHolder<'a> {
 254         pub(super) by_id: &'a mut HashMap<[u8; 32], Channel>,
 255         pub(super) short_to_id: &'a mut HashMap<u64, [u8; 32]>,
 256         pub(super) next_forward: &'a mut Instant,
 257         pub(super) forward_htlcs: &'a mut HashMap<u64, Vec<HTLCForwardInfo>>,
 258         pub(super) claimable_htlcs: &'a mut HashMap<PaymentHash, Vec<HTLCPreviousHopData>>,
 259         pub(super) pending_msg_events: &'a mut Vec<events::MessageSendEvent>,
 260 }
 261 impl ChannelHolder {
 262         pub(super) fn borrow_parts(&mut self) -> MutChannelHolder {
 263                 MutChannelHolder {
 264                         by_id: &mut self.by_id,
 265                         short_to_id: &mut self.short_to_id,
 266                         next_forward: &mut self.next_forward,
 267                         forward_htlcs: &mut self.forward_htlcs,
 268                         claimable_htlcs: &mut self.claimable_htlcs,
 269                         pending_msg_events: &mut self.pending_msg_events,
 270                 }
 271         }
 272 }
 273
 274 #[cfg(not(any(target_pointer_width = "32", target_pointer_width = "64")))]
 275 const ERR: () = "You need at least 32 bit pointers (well, usize, but we'll assume they're the same) for ChannelManager::latest_block_height";
 276
 277 /// Manager which keeps track of a number of channels and sends messages to the appropriate
 278 /// channel, also tracking HTLC preimages and forwarding onion packets appropriately.
 279 ///
 280 /// Implements ChannelMessageHandler, handling the multi-channel parts and passing things through
 281 /// to individual Channels.
 282 ///
 283 /// Implements Writeable to write out all channel state to disk. Implies peer_disconnected() for
 284 /// all peers during write/read (though does not modify this instance, only the instance being
 285 /// serialized). This will result in any channels which have not yet exchanged funding_created (ie
 286 /// called funding_transaction_generated for outbound channels).
 287 ///
 288 /// Note that you can be a bit lazier about writing out ChannelManager than you can be with
 289 /// ChannelMonitors. With ChannelMonitors you MUST write each monitor update out to disk before
 290 /// returning from ManyChannelMonitor::add_update_monitor, with ChannelManagers, writing updates
 291 /// happens out-of-band (and will prevent any other ChannelManager operations from occurring during
 292 /// the serialization process). If the deserialized version is out-of-date compared to the
 293 /// ChannelMonitors passed by reference to read(), those channels will be force-closed based on the
 294 /// ChannelMonitor state and no funds will be lost (mod on-chain transaction fees).
 295 ///
 296 /// Note that the deserializer is only implemented for (Sha256dHash, ChannelManager), which
 297 /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
 298 /// the "reorg path" (ie call block_disconnected() until you get to a common block and then call
 299 /// block_connected() to step towards your best block) upon deserialization before using the
 300 /// object!
 301 pub struct ChannelManager {
 302         default_configuration: UserConfig,
 303         genesis_hash: Sha256dHash,
 304         fee_estimator: Arc<FeeEstimator>,
 305         monitor: Arc<ManyChannelMonitor>,
 306         chain_monitor: Arc<ChainWatchInterface>,
 307         tx_broadcaster: Arc<BroadcasterInterface>,
 308
 309         #[cfg(test)]
 310         pub(super) latest_block_height: AtomicUsize,
 311         #[cfg(not(test))]
 312         latest_block_height: AtomicUsize,
 313         last_block_hash: Mutex<Sha256dHash>,
 314         secp_ctx: Secp256k1<secp256k1::All>,
 315
 316         #[cfg(test)]
 317         pub(super) channel_state: Mutex<ChannelHolder>,
 318         #[cfg(not(test))]
 319         channel_state: Mutex<ChannelHolder>,
 320         our_network_key: SecretKey,
 321
 322         pending_events: Mutex<Vec<events::Event>>,
 323         /// Used when we have to take a BIG lock to make sure everything is self-consistent.
 324         /// Essentially just when we're serializing ourselves out.
 325         /// Taken first everywhere where we are making changes before any other locks.
 326         total_consistency_lock: RwLock<()>,
 327
 328         keys_manager: Arc<KeysInterface>,
 329
 330         logger: Arc<Logger>,
 331 }
 332
 333 /// The minimum number of blocks between an inbound HTLC's CLTV and the corresponding outbound
 334 /// HTLC's CLTV. This should always be a few blocks greater than channelmonitor::CLTV_CLAIM_BUFFER,
 335 /// ie the node we forwarded the payment on to should always have enough room to reliably time out
 336 /// the HTLC via a full update_fail_htlc/commitment_signed dance before we hit the
 337 /// CLTV_CLAIM_BUFFER point (we static assert that its at least 3 blocks more).
 338 const CLTV_EXPIRY_DELTA: u16 = 6 * 12; //TODO?
 339 pub(super) const CLTV_FAR_FAR_AWAY: u32 = 6 * 24 * 7; //TODO?
 340
 341 // Check that our CLTV_EXPIRY is at least CLTV_CLAIM_BUFFER + 2*HTLC_FAIL_TIMEOUT_BLOCKS +
 342 // HTLC_FAIL_ANTI_REORG_DELAY, ie that if the next-hop peer fails the HTLC within
 343 // HTLC_FAIL_TIMEOUT_BLOCKS then we'll still have HTLC_FAIL_TIMEOUT_BLOCKS left to fail it
 344 // backwards ourselves before hitting the CLTV_CLAIM_BUFFER point and failing the channel
 345 // on-chain to time out the HTLC.
 346 #[deny(const_err)]
 347 #[allow(dead_code)]
 348 const CHECK_CLTV_EXPIRY_SANITY: u32 = CLTV_EXPIRY_DELTA as u32 - 2*HTLC_FAIL_TIMEOUT_BLOCKS - CLTV_CLAIM_BUFFER - HTLC_FAIL_ANTI_REORG_DELAY;
 349
 350 // Check for ability of an attacker to make us fail on-chain by delaying inbound claim. See
 351 // ChannelMontior::would_broadcast_at_height for a description of why this is needed.
 352 #[deny(const_err)]
 353 #[allow(dead_code)]
 354 const CHECK_CLTV_EXPIRY_SANITY_2: u32 = CLTV_EXPIRY_DELTA as u32 - HTLC_FAIL_TIMEOUT_BLOCKS - 2*CLTV_CLAIM_BUFFER;
 355
 356 macro_rules! secp_call {
 357         ( $res: expr, $err: expr ) => {
 358                 match $res {
 359                         Ok(key) => key,
 360                         Err(_) => return Err($err),
 361                 }
 362         };
 363 }
 364
 365 /// Details of a channel, as returned by ChannelManager::list_channels and ChannelManager::list_usable_channels
 366 pub struct ChannelDetails {
 367         /// The channel's ID (prior to funding transaction generation, this is a random 32 bytes,
 368         /// thereafter this is the txid of the funding transaction xor the funding transaction output).
 369         /// Note that this means this value is *not* persistent - it can change once during the
 370         /// lifetime of the channel.
 371         pub channel_id: [u8; 32],
 372         /// The position of the funding transaction in the chain. None if the funding transaction has
 373         /// not yet been confirmed and the channel fully opened.
 374         pub short_channel_id: Option<u64>,
 375         /// The node_id of our counterparty
 376         pub remote_network_id: PublicKey,
 377         /// The value, in satoshis, of this channel as appears in the funding output
 378         pub channel_value_satoshis: u64,
 379         /// The user_id passed in to create_channel, or 0 if the channel was inbound.
 380         pub user_id: u64,
 381 }
 382
 383 macro_rules! handle_error {
 384         ($self: ident, $internal: expr, $their_node_id: expr) => {
 385                 match $internal {
 386                         Ok(msg) => Ok(msg),
 387                         Err(MsgHandleErrInternal { err, shutdown_finish }) => {
 388                                 if let Some((shutdown_res, update_option)) = shutdown_finish {
 389                                         $self.finish_force_close_channel(shutdown_res);
 390                                         if let Some(update) = update_option {
 391                                                 let mut channel_state = $self.channel_state.lock().unwrap();
 392                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
 393                                                         msg: update
 394                                                 });
 395                                         }
 396                                 }
 397                                 Err(err)
 398                         },
 399                 }
 400         }
 401 }
 402
 403 macro_rules! break_chan_entry {
 404         ($self: ident, $res: expr, $channel_state: expr, $entry: expr) => {
 405                 match $res {
 406                         Ok(res) => res,
 407                         Err(ChannelError::Ignore(msg)) => {
 408                                 break Err(MsgHandleErrInternal::from_chan_no_close(ChannelError::Ignore(msg), $entry.key().clone()))
 409                         },
 410                         Err(ChannelError::Close(msg)) => {
 411                                 log_trace!($self, "Closing channel {} due to Close-required error: {}", log_bytes!($entry.key()[..]), msg);
 412                                 let (channel_id, mut chan) = $entry.remove_entry();
 413                                 if let Some(short_id) = chan.get_short_channel_id() {
 414                                         $channel_state.short_to_id.remove(&short_id);
 415                                 }
 416                                 break Err(MsgHandleErrInternal::from_finish_shutdown(msg, channel_id, chan.force_shutdown(), $self.get_channel_update(&chan).ok()))
 417                         },
 418                 }
 419         }
 420 }
 421
 422 macro_rules! try_chan_entry {
 423         ($self: ident, $res: expr, $channel_state: expr, $entry: expr) => {
 424                 match $res {
 425                         Ok(res) => res,
 426                         Err(ChannelError::Ignore(msg)) => {
 427                                 return Err(MsgHandleErrInternal::from_chan_no_close(ChannelError::Ignore(msg), $entry.key().clone()))
 428                         },
 429                         Err(ChannelError::Close(msg)) => {
 430                                 log_trace!($self, "Closing channel {} due to Close-required error: {}", log_bytes!($entry.key()[..]), msg);
 431                                 let (channel_id, mut chan) = $entry.remove_entry();
 432                                 if let Some(short_id) = chan.get_short_channel_id() {
 433                                         $channel_state.short_to_id.remove(&short_id);
 434                                 }
 435                                 return Err(MsgHandleErrInternal::from_finish_shutdown(msg, channel_id, chan.force_shutdown(), $self.get_channel_update(&chan).ok()))
 436                         },
 437                 }
 438         }
 439 }
 440
 441 macro_rules! return_monitor_err {
 442         ($self: expr, $err: expr, $channel_state: expr, $entry: expr, $action_type: path) => {
 443                 return_monitor_err!($self, $err, $channel_state, $entry, $action_type, Vec::new(), Vec::new())
 444         };
 445         ($self: expr, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $raa_first_dropped_cs: expr) => {
 446                 if $action_type != RAACommitmentOrder::RevokeAndACKFirst { panic!("Bad return_monitor_err call!"); }
 447                 return_monitor_err!($self, $err, $channel_state, $entry, $action_type, Vec::new(), Vec::new(), $raa_first_dropped_cs)
 448         };
 449         ($self: expr, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $failed_forwards: expr, $failed_fails: expr) => {
 450                 return_monitor_err!($self, $err, $channel_state, $entry, $action_type, $failed_forwards, $failed_fails, false)
 451         };
 452         ($self: expr, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $failed_forwards: expr, $failed_fails: expr, $raa_first_dropped_cs: expr) => {
 453                 match $err {
 454                         ChannelMonitorUpdateErr::PermanentFailure => {
 455                                 let (channel_id, mut chan) = $entry.remove_entry();
 456                                 if let Some(short_id) = chan.get_short_channel_id() {
 457                                         $channel_state.short_to_id.remove(&short_id);
 458                                 }
 459                                 // TODO: $failed_fails is dropped here, which will cause other channels to hit the
 460                                 // chain in a confused state! We need to move them into the ChannelMonitor which
 461                                 // will be responsible for failing backwards once things confirm on-chain.
 462                                 // It's ok that we drop $failed_forwards here - at this point we'd rather they
 463                                 // broadcast HTLC-Timeout and pay the associated fees to get their funds back than
 464                                 // us bother trying to claim it just to forward on to another peer. If we're
 465                                 // splitting hairs we'd prefer to claim payments that were to us, but we haven't
 466                                 // given up the preimage yet, so might as well just wait until the payment is
 467                                 // retried, avoiding the on-chain fees.
 468                                 return Err(MsgHandleErrInternal::from_finish_shutdown("ChannelMonitor storage failure", channel_id, chan.force_shutdown(), $self.get_channel_update(&chan).ok()))
 469                         },
 470                         ChannelMonitorUpdateErr::TemporaryFailure => {
 471                                 $entry.get_mut().monitor_update_failed($action_type, $failed_forwards, $failed_fails, $raa_first_dropped_cs);
 472                                 return Err(MsgHandleErrInternal::from_chan_no_close(ChannelError::Ignore("Failed to update ChannelMonitor"), *$entry.key()));
 473                         },
 474                 }
 475         }
 476 }
 477
 478 // Does not break in case of TemporaryFailure!
 479 macro_rules! maybe_break_monitor_err {
 480         ($self: expr, $err: expr, $channel_state: expr, $entry: expr, $action_type: path) => {
 481                 match $err {
 482                         ChannelMonitorUpdateErr::PermanentFailure => {
 483                                 let (channel_id, mut chan) = $entry.remove_entry();
 484                                 if let Some(short_id) = chan.get_short_channel_id() {
 485                                         $channel_state.short_to_id.remove(&short_id);
 486                                 }
 487                                 break Err(MsgHandleErrInternal::from_finish_shutdown("ChannelMonitor storage failure", channel_id, chan.force_shutdown(), $self.get_channel_update(&chan).ok()))
 488                         },
 489                         ChannelMonitorUpdateErr::TemporaryFailure => {
 490                                 $entry.get_mut().monitor_update_failed($action_type, Vec::new(), Vec::new(), false);
 491                         },
 492                 }
 493         }
 494 }
 495
 496 impl ChannelManager {
 497         /// Constructs a new ChannelManager to hold several channels and route between them.
 498         ///
 499         /// This is the main "logic hub" for all channel-related actions, and implements
 500         /// ChannelMessageHandler.
 501         ///
 502         /// Non-proportional fees are fixed according to our risk using the provided fee estimator.
 503         ///
 504         /// panics if channel_value_satoshis is >= `MAX_FUNDING_SATOSHIS`!
 505         pub fn new(network: Network, feeest: Arc<FeeEstimator>, monitor: Arc<ManyChannelMonitor>, chain_monitor: Arc<ChainWatchInterface>, tx_broadcaster: Arc<BroadcasterInterface>, logger: Arc<Logger>,keys_manager: Arc<KeysInterface>, config: UserConfig) -> Result<Arc<ChannelManager>, secp256k1::Error> {
 506                 let secp_ctx = Secp256k1::new();
 507
 508                 let res = Arc::new(ChannelManager {
 509                         default_configuration: config.clone(),
 510                         genesis_hash: genesis_block(network).header.bitcoin_hash(),
 511                         fee_estimator: feeest.clone(),
 512                         monitor: monitor.clone(),
 513                         chain_monitor,
 514                         tx_broadcaster,
 515
 516                         latest_block_height: AtomicUsize::new(0), //TODO: Get an init value
 517                         last_block_hash: Mutex::new(Default::default()),
 518                         secp_ctx,
 519
 520                         channel_state: Mutex::new(ChannelHolder{
 521                                 by_id: HashMap::new(),
 522                                 short_to_id: HashMap::new(),
 523                                 next_forward: Instant::now(),
 524                                 forward_htlcs: HashMap::new(),
 525                                 claimable_htlcs: HashMap::new(),
 526                                 pending_msg_events: Vec::new(),
 527                         }),
 528                         our_network_key: keys_manager.get_node_secret(),
 529
 530                         pending_events: Mutex::new(Vec::new()),
 531                         total_consistency_lock: RwLock::new(()),
 532
 533                         keys_manager,
 534
 535                         logger,
 536                 });
 537                 let weak_res = Arc::downgrade(&res);
 538                 res.chain_monitor.register_listener(weak_res);
 539                 Ok(res)
 540         }
 541
 542         /// Creates a new outbound channel to the given remote node and with the given value.
 543         ///
 544         /// user_id will be provided back as user_channel_id in FundingGenerationReady and
 545         /// FundingBroadcastSafe events to allow tracking of which events correspond with which
 546         /// create_channel call. Note that user_channel_id defaults to 0 for inbound channels, so you
 547         /// may wish to avoid using 0 for user_id here.
 548         ///
 549         /// If successful, will generate a SendOpenChannel message event, so you should probably poll
 550         /// PeerManager::process_events afterwards.
 551         ///
 552         /// Raises APIError::APIMisuseError when channel_value_satoshis > 2**24 or push_msat is
 553         /// greater than channel_value_satoshis * 1k or channel_value_satoshis is < 1000.
 554         pub fn create_channel(&self, their_network_key: PublicKey, channel_value_satoshis: u64, push_msat: u64, user_id: u64) -> Result<(), APIError> {
 555                 if channel_value_satoshis < 1000 {
 556                         return Err(APIError::APIMisuseError { err: "channel_value must be at least 1000 satoshis" });
 557                 }
 558
 559                 let channel = Channel::new_outbound(&*self.fee_estimator, &self.keys_manager, their_network_key, channel_value_satoshis, push_msat, user_id, Arc::clone(&self.logger), &self.default_configuration)?;
 560                 let res = channel.get_open_channel(self.genesis_hash.clone(), &*self.fee_estimator);
 561
 562                 let _ = self.total_consistency_lock.read().unwrap();
 563                 let mut channel_state = self.channel_state.lock().unwrap();
 564                 match channel_state.by_id.entry(channel.channel_id()) {
 565                         hash_map::Entry::Occupied(_) => {
 566                                 if cfg!(feature = "fuzztarget") {
 567                                         return Err(APIError::APIMisuseError { err: "Fuzzy bad RNG" });
 568                                 } else {
 569                                         panic!("RNG is bad???");
 570                                 }
 571                         },
 572                         hash_map::Entry::Vacant(entry) => { entry.insert(channel); }
 573                 }
 574                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendOpenChannel {
 575                         node_id: their_network_key,
 576                         msg: res,
 577                 });
 578                 Ok(())
 579         }
 580
 581         /// Gets the list of open channels, in random order. See ChannelDetail field documentation for
 582         /// more information.
 583         pub fn list_channels(&self) -> Vec<ChannelDetails> {
 584                 let channel_state = self.channel_state.lock().unwrap();
 585                 let mut res = Vec::with_capacity(channel_state.by_id.len());
 586                 for (channel_id, channel) in channel_state.by_id.iter() {
 587                         res.push(ChannelDetails {
 588                                 channel_id: (*channel_id).clone(),
 589                                 short_channel_id: channel.get_short_channel_id(),
 590                                 remote_network_id: channel.get_their_node_id(),
 591                                 channel_value_satoshis: channel.get_value_satoshis(),
 592                                 user_id: channel.get_user_id(),
 593                         });
 594                 }
 595                 res
 596         }
 597
 598         /// Gets the list of usable channels, in random order. Useful as an argument to
 599         /// Router::get_route to ensure non-announced channels are used.
 600         pub fn list_usable_channels(&self) -> Vec<ChannelDetails> {
 601                 let channel_state = self.channel_state.lock().unwrap();
 602                 let mut res = Vec::with_capacity(channel_state.by_id.len());
 603                 for (channel_id, channel) in channel_state.by_id.iter() {
 604                         // Note we use is_live here instead of usable which leads to somewhat confused
 605                         // internal/external nomenclature, but that's ok cause that's probably what the user
 606                         // really wanted anyway.
 607                         if channel.is_live() {
 608                                 res.push(ChannelDetails {
 609                                         channel_id: (*channel_id).clone(),
 610                                         short_channel_id: channel.get_short_channel_id(),
 611                                         remote_network_id: channel.get_their_node_id(),
 612                                         channel_value_satoshis: channel.get_value_satoshis(),
 613                                         user_id: channel.get_user_id(),
 614                                 });
 615                         }
 616                 }
 617                 res
 618         }
 619
 620         /// Begins the process of closing a channel. After this call (plus some timeout), no new HTLCs
 621         /// will be accepted on the given channel, and after additional timeout/the closing of all
 622         /// pending HTLCs, the channel will be closed on chain.
 623         ///
 624         /// May generate a SendShutdown message event on success, which should be relayed.
 625         pub fn close_channel(&self, channel_id: &[u8; 32]) -> Result<(), APIError> {
 626                 let _ = self.total_consistency_lock.read().unwrap();
 627
 628                 let (mut failed_htlcs, chan_option) = {
 629                         let mut channel_state_lock = self.channel_state.lock().unwrap();
 630                         let channel_state = channel_state_lock.borrow_parts();
 631                         match channel_state.by_id.entry(channel_id.clone()) {
 632                                 hash_map::Entry::Occupied(mut chan_entry) => {
 633                                         let (shutdown_msg, failed_htlcs) = chan_entry.get_mut().get_shutdown()?;
 634                                         channel_state.pending_msg_events.push(events::MessageSendEvent::SendShutdown {
 635                                                 node_id: chan_entry.get().get_their_node_id(),
 636                                                 msg: shutdown_msg
 637                                         });
 638                                         if chan_entry.get().is_shutdown() {
 639                                                 if let Some(short_id) = chan_entry.get().get_short_channel_id() {
 640                                                         channel_state.short_to_id.remove(&short_id);
 641                                                 }
 642                                                 (failed_htlcs, Some(chan_entry.remove_entry().1))
 643                                         } else { (failed_htlcs, None) }
 644                                 },
 645                                 hash_map::Entry::Vacant(_) => return Err(APIError::ChannelUnavailable{err: "No such channel"})
 646                         }
 647                 };
 648                 for htlc_source in failed_htlcs.drain(..) {
 649                         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() });
 650                 }
 651                 let chan_update = if let Some(chan) = chan_option {
 652                         if let Ok(update) = self.get_channel_update(&chan) {
 653                                 Some(update)
 654                         } else { None }
 655                 } else { None };
 656
 657                 if let Some(update) = chan_update {
 658                         let mut channel_state = self.channel_state.lock().unwrap();
 659                         channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
 660                                 msg: update
 661                         });
 662                 }
 663
 664                 Ok(())
 665         }
 666
 667         #[inline]
 668         fn finish_force_close_channel(&self, shutdown_res: ShutdownResult) {
 669                 let (local_txn, mut failed_htlcs) = shutdown_res;
 670                 log_trace!(self, "Finishing force-closure of channel with {} transactions to broadcast and {} HTLCs to fail", local_txn.len(), failed_htlcs.len());
 671                 for htlc_source in failed_htlcs.drain(..) {
 672                         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() });
 673                 }
 674                 for tx in local_txn {
 675                         self.tx_broadcaster.broadcast_transaction(&tx);
 676                 }
 677         }
 678
 679         /// Force closes a channel, immediately broadcasting the latest local commitment transaction to
 680         /// the chain and rejecting new HTLCs on the given channel.
 681         pub fn force_close_channel(&self, channel_id: &[u8; 32]) {
 682                 let _ = self.total_consistency_lock.read().unwrap();
 683
 684                 let mut chan = {
 685                         let mut channel_state_lock = self.channel_state.lock().unwrap();
 686                         let channel_state = channel_state_lock.borrow_parts();
 687                         if let Some(chan) = channel_state.by_id.remove(channel_id) {
 688                                 if let Some(short_id) = chan.get_short_channel_id() {
 689                                         channel_state.short_to_id.remove(&short_id);
 690                                 }
 691                                 chan
 692                         } else {
 693                                 return;
 694                         }
 695                 };
 696                 log_trace!(self, "Force-closing channel {}", log_bytes!(channel_id[..]));
 697                 self.finish_force_close_channel(chan.force_shutdown());
 698                 if let Ok(update) = self.get_channel_update(&chan) {
 699                         let mut channel_state = self.channel_state.lock().unwrap();
 700                         channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
 701                                 msg: update
 702                         });
 703                 }
 704         }
 705
 706         /// Force close all channels, immediately broadcasting the latest local commitment transaction
 707         /// for each to the chain and rejecting new HTLCs on each.
 708         pub fn force_close_all_channels(&self) {
 709                 for chan in self.list_channels() {
 710                         self.force_close_channel(&chan.channel_id);
 711                 }
 712         }
 713
 714         const ZERO:[u8; 65] = [0; 65];
 715         fn decode_update_add_htlc_onion(&self, msg: &msgs::UpdateAddHTLC) -> (PendingHTLCStatus, MutexGuard<ChannelHolder>) {
 716                 macro_rules! return_malformed_err {
 717                         ($msg: expr, $err_code: expr) => {
 718                                 {
 719                                         log_info!(self, "Failed to accept/forward incoming HTLC: {}", $msg);
 720                                         return (PendingHTLCStatus::Fail(HTLCFailureMsg::Malformed(msgs::UpdateFailMalformedHTLC {
 721                                                 channel_id: msg.channel_id,
 722                                                 htlc_id: msg.htlc_id,
 723                                                 sha256_of_onion: Sha256::hash(&msg.onion_routing_packet.hop_data).into_inner(),
 724                                                 failure_code: $err_code,
 725                                         })), self.channel_state.lock().unwrap());
 726                                 }
 727                         }
 728                 }
 729
 730                 if let Err(_) = msg.onion_routing_packet.public_key {
 731                         return_malformed_err!("invalid ephemeral pubkey", 0x8000 | 0x4000 | 6);
 732                 }
 733
 734                 let shared_secret = {
 735                         let mut arr = [0; 32];
 736                         arr.copy_from_slice(&SharedSecret::new(&self.secp_ctx, &msg.onion_routing_packet.public_key.unwrap(), &self.our_network_key)[..]);
 737                         arr
 738                 };
 739                 let (rho, mu) = onion_utils::gen_rho_mu_from_shared_secret(&shared_secret);
 740
 741                 if msg.onion_routing_packet.version != 0 {
 742                         //TODO: Spec doesn't indicate if we should only hash hop_data here (and in other
 743                         //sha256_of_onion error data packets), or the entire onion_routing_packet. Either way,
 744                         //the hash doesn't really serve any purpuse - in the case of hashing all data, the
 745                         //receiving node would have to brute force to figure out which version was put in the
 746                         //packet by the node that send us the message, in the case of hashing the hop_data, the
 747                         //node knows the HMAC matched, so they already know what is there...
 748                         return_malformed_err!("Unknown onion packet version", 0x8000 | 0x4000 | 4);
 749                 }
 750
 751                 let mut hmac = HmacEngine::<Sha256>::new(&mu);
 752                 hmac.input(&msg.onion_routing_packet.hop_data);
 753                 hmac.input(&msg.payment_hash.0[..]);
 754                 if !fixed_time_eq(&Hmac::from_engine(hmac).into_inner(), &msg.onion_routing_packet.hmac) {
 755                         return_malformed_err!("HMAC Check failed", 0x8000 | 0x4000 | 5);
 756                 }
 757
 758                 let mut channel_state = None;
 759                 macro_rules! return_err {
 760                         ($msg: expr, $err_code: expr, $data: expr) => {
 761                                 {
 762                                         log_info!(self, "Failed to accept/forward incoming HTLC: {}", $msg);
 763                                         if channel_state.is_none() {
 764                                                 channel_state = Some(self.channel_state.lock().unwrap());
 765                                         }
 766                                         return (PendingHTLCStatus::Fail(HTLCFailureMsg::Relay(msgs::UpdateFailHTLC {
 767                                                 channel_id: msg.channel_id,
 768                                                 htlc_id: msg.htlc_id,
 769                                                 reason: onion_utils::build_first_hop_failure_packet(&shared_secret, $err_code, $data),
 770                                         })), channel_state.unwrap());
 771                                 }
 772                         }
 773                 }
 774
 775                 let mut chacha = ChaCha20::new(&rho, &[0u8; 8]);
 776                 let next_hop_data = {
 777                         let mut decoded = [0; 65];
 778                         chacha.process(&msg.onion_routing_packet.hop_data[0..65], &mut decoded);
 779                         match msgs::OnionHopData::read(&mut Cursor::new(&decoded[..])) {
 780                                 Err(err) => {
 781                                         let error_code = match err {
 782                                                 msgs::DecodeError::UnknownVersion => 0x4000 | 1, // unknown realm byte
 783                                                 _ => 0x2000 | 2, // Should never happen
 784                                         };
 785                                         return_err!("Unable to decode our hop data", error_code, &[0;0]);
 786                                 },
 787                                 Ok(msg) => msg
 788                         }
 789                 };
 790
 791                 let pending_forward_info = if next_hop_data.hmac == [0; 32] {
 792                                 // OUR PAYMENT!
 793                                 // final_expiry_too_soon
 794                                 if (msg.cltv_expiry as u64) < self.latest_block_height.load(Ordering::Acquire) as u64 + (CLTV_CLAIM_BUFFER + HTLC_FAIL_TIMEOUT_BLOCKS) as u64 {
 795                                         return_err!("The final CLTV expiry is too soon to handle", 17, &[0;0]);
 796                                 }
 797                                 // final_incorrect_htlc_amount
 798                                 if next_hop_data.data.amt_to_forward > msg.amount_msat {
 799                                         return_err!("Upstream node sent less than we were supposed to receive in payment", 19, &byte_utils::be64_to_array(msg.amount_msat));
 800                                 }
 801                                 // final_incorrect_cltv_expiry
 802                                 if next_hop_data.data.outgoing_cltv_value != msg.cltv_expiry {
 803                                         return_err!("Upstream node set CLTV to the wrong value", 18, &byte_utils::be32_to_array(msg.cltv_expiry));
 804                                 }
 805
 806                                 // Note that we could obviously respond immediately with an update_fulfill_htlc
 807                                 // message, however that would leak that we are the recipient of this payment, so
 808                                 // instead we stay symmetric with the forwarding case, only responding (after a
 809                                 // delay) once they've send us a commitment_signed!
 810
 811                                 PendingHTLCStatus::Forward(PendingForwardHTLCInfo {
 812                                         onion_packet: None,
 813                                         payment_hash: msg.payment_hash.clone(),
 814                                         short_channel_id: 0,
 815                                         incoming_shared_secret: shared_secret,
 816                                         amt_to_forward: next_hop_data.data.amt_to_forward,
 817                                         outgoing_cltv_value: next_hop_data.data.outgoing_cltv_value,
 818                                 })
 819                         } else {
 820                                 let mut new_packet_data = [0; 20*65];
 821                                 chacha.process(&msg.onion_routing_packet.hop_data[65..], &mut new_packet_data[0..19*65]);
 822                                 chacha.process(&ChannelManager::ZERO[..], &mut new_packet_data[19*65..]);
 823
 824                                 let mut new_pubkey = msg.onion_routing_packet.public_key.unwrap();
 825
 826                                 let blinding_factor = {
 827                                         let mut sha = Sha256::engine();
 828                                         sha.input(&new_pubkey.serialize()[..]);
 829                                         sha.input(&shared_secret);
 830                                         SecretKey::from_slice(&self.secp_ctx, &Sha256::from_engine(sha).into_inner()).expect("SHA-256 is broken?")
 831                                 };
 832
 833                                 let public_key = if let Err(e) = new_pubkey.mul_assign(&self.secp_ctx, &blinding_factor) {
 834                                         Err(e)
 835                                 } else { Ok(new_pubkey) };
 836
 837                                 let outgoing_packet = msgs::OnionPacket {
 838                                         version: 0,
 839                                         public_key,
 840                                         hop_data: new_packet_data,
 841                                         hmac: next_hop_data.hmac.clone(),
 842                                 };
 843
 844                                 PendingHTLCStatus::Forward(PendingForwardHTLCInfo {
 845                                         onion_packet: Some(outgoing_packet),
 846                                         payment_hash: msg.payment_hash.clone(),
 847                                         short_channel_id: next_hop_data.data.short_channel_id,
 848                                         incoming_shared_secret: shared_secret,
 849                                         amt_to_forward: next_hop_data.data.amt_to_forward,
 850                                         outgoing_cltv_value: next_hop_data.data.outgoing_cltv_value,
 851                                 })
 852                         };
 853
 854                 channel_state = Some(self.channel_state.lock().unwrap());
 855                 if let &PendingHTLCStatus::Forward(PendingForwardHTLCInfo { ref onion_packet, ref short_channel_id, ref amt_to_forward, ref outgoing_cltv_value, .. }) = &pending_forward_info {
 856                         if onion_packet.is_some() { // If short_channel_id is 0 here, we'll reject them in the body here
 857                                 let id_option = channel_state.as_ref().unwrap().short_to_id.get(&short_channel_id).cloned();
 858                                 let forwarding_id = match id_option {
 859                                         None => { // unknown_next_peer
 860                                                 return_err!("Don't have available channel for forwarding as requested.", 0x4000 | 10, &[0;0]);
 861                                         },
 862                                         Some(id) => id.clone(),
 863                                 };
 864                                 if let Some((err, code, chan_update)) = loop {
 865                                         let chan = channel_state.as_mut().unwrap().by_id.get_mut(&forwarding_id).unwrap();
 866
 867                                         // Note that we could technically not return an error yet here and just hope
 868                                         // that the connection is reestablished or monitor updated by the time we get
 869                                         // around to doing the actual forward, but better to fail early if we can and
 870                                         // hopefully an attacker trying to path-trace payments cannot make this occur
 871                                         // on a small/per-node/per-channel scale.
 872                                         if !chan.is_live() { // channel_disabled
 873                                                 break Some(("Forwarding channel is not in a ready state.", 0x1000 | 20, Some(self.get_channel_update(chan).unwrap())));
 874                                         }
 875                                         if *amt_to_forward < chan.get_their_htlc_minimum_msat() { // amount_below_minimum
 876                                                 break Some(("HTLC amount was below the htlc_minimum_msat", 0x1000 | 11, Some(self.get_channel_update(chan).unwrap())));
 877                                         }
 878                                         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) });
 879                                         if fee.is_none() || msg.amount_msat < fee.unwrap() || (msg.amount_msat - fee.unwrap()) < *amt_to_forward { // fee_insufficient
 880                                                 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())));
 881                                         }
 882                                         if (msg.cltv_expiry as u64) < (*outgoing_cltv_value) as u64 + CLTV_EXPIRY_DELTA as u64 { // incorrect_cltv_expiry
 883                                                 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())));
 884                                         }
 885                                         let cur_height = self.latest_block_height.load(Ordering::Acquire) as u32 + 1;
 886                                         // We want to have at least HTLC_FAIL_TIMEOUT_BLOCKS to fail prior to going on chain CLAIM_BUFFER blocks before expiration
 887                                         if msg.cltv_expiry <= cur_height + CLTV_CLAIM_BUFFER + HTLC_FAIL_TIMEOUT_BLOCKS as u32 { // expiry_too_soon
 888                                                 break Some(("CLTV expiry is too close", 0x1000 | 14, Some(self.get_channel_update(chan).unwrap())));
 889                                         }
 890                                         if msg.cltv_expiry > cur_height + CLTV_FAR_FAR_AWAY as u32 { // expiry_too_far
 891                                                 break Some(("CLTV expiry is too far in the future", 21, None));
 892                                         }
 893                                         break None;
 894                                 }
 895                                 {
 896                                         let mut res = Vec::with_capacity(8 + 128);
 897                                         if let Some(chan_update) = chan_update {
 898                                                 if code == 0x1000 | 11 || code == 0x1000 | 12 {
 899                                                         res.extend_from_slice(&byte_utils::be64_to_array(msg.amount_msat));
 900                                                 }
 901                                                 else if code == 0x1000 | 13 {
 902                                                         res.extend_from_slice(&byte_utils::be32_to_array(msg.cltv_expiry));
 903                                                 }
 904                                                 else if code == 0x1000 | 20 {
 905                                                         res.extend_from_slice(&byte_utils::be16_to_array(chan_update.contents.flags));
 906                                                 }
 907                                                 res.extend_from_slice(&chan_update.encode_with_len()[..]);
 908                                         }
 909                                         return_err!(err, code, &res[..]);
 910                                 }
 911                         }
 912                 }
 913
 914                 (pending_forward_info, channel_state.unwrap())
 915         }
 916
 917         /// only fails if the channel does not yet have an assigned short_id
 918         /// May be called with channel_state already locked!
 919         fn get_channel_update(&self, chan: &Channel) -> Result<msgs::ChannelUpdate, HandleError> {
 920                 let short_channel_id = match chan.get_short_channel_id() {
 921                         None => return Err(HandleError{err: "Channel not yet established", action: None}),
 922                         Some(id) => id,
 923                 };
 924
 925                 let were_node_one = PublicKey::from_secret_key(&self.secp_ctx, &self.our_network_key).serialize()[..] < chan.get_their_node_id().serialize()[..];
 926
 927                 let unsigned = msgs::UnsignedChannelUpdate {
 928                         chain_hash: self.genesis_hash,
 929                         short_channel_id: short_channel_id,
 930                         timestamp: chan.get_channel_update_count(),
 931                         flags: (!were_node_one) as u16 | ((!chan.is_live() as u16) << 1),
 932                         cltv_expiry_delta: CLTV_EXPIRY_DELTA,
 933                         htlc_minimum_msat: chan.get_our_htlc_minimum_msat(),
 934                         fee_base_msat: chan.get_our_fee_base_msat(&*self.fee_estimator),
 935                         fee_proportional_millionths: chan.get_fee_proportional_millionths(),
 936                         excess_data: Vec::new(),
 937                 };
 938
 939                 let msg_hash = Sha256dHash::from_data(&unsigned.encode()[..]);
 940                 let sig = self.secp_ctx.sign(&Message::from_slice(&msg_hash[..]).unwrap(), &self.our_network_key);
 941
 942                 Ok(msgs::ChannelUpdate {
 943                         signature: sig,
 944                         contents: unsigned
 945                 })
 946         }
 947
 948         /// Sends a payment along a given route.
 949         ///
 950         /// Value parameters are provided via the last hop in route, see documentation for RouteHop
 951         /// fields for more info.
 952         ///
 953         /// Note that if the payment_hash already exists elsewhere (eg you're sending a duplicative
 954         /// payment), we don't do anything to stop you! We always try to ensure that if the provided
 955         /// next hop knows the preimage to payment_hash they can claim an additional amount as
 956         /// specified in the last hop in the route! Thus, you should probably do your own
 957         /// payment_preimage tracking (which you should already be doing as they represent "proof of
 958         /// payment") and prevent double-sends yourself.
 959         ///
 960         /// May generate a SendHTLCs message event on success, which should be relayed.
 961         ///
 962         /// Raises APIError::RoutError when invalid route or forward parameter
 963         /// (cltv_delta, fee, node public key) is specified.
 964         /// Raises APIError::ChannelUnavailable if the next-hop channel is not available for updates
 965         /// (including due to previous monitor update failure or new permanent monitor update failure).
 966         /// Raised APIError::MonitorUpdateFailed if a new monitor update failure prevented sending the
 967         /// relevant updates.
 968         ///
 969         /// In case of APIError::RouteError/APIError::ChannelUnavailable, the payment send has failed
 970         /// and you may wish to retry via a different route immediately.
 971         /// In case of APIError::MonitorUpdateFailed, the commitment update has been irrevocably
 972         /// committed on our end and we're just waiting for a monitor update to send it. Do NOT retry
 973         /// the payment via a different route unless you intend to pay twice!
 974         pub fn send_payment(&self, route: Route, payment_hash: PaymentHash) -> Result<(), APIError> {
 975                 if route.hops.len() < 1 || route.hops.len() > 20 {
 976                         return Err(APIError::RouteError{err: "Route didn't go anywhere/had bogus size"});
 977                 }
 978                 let our_node_id = self.get_our_node_id();
 979                 for (idx, hop) in route.hops.iter().enumerate() {
 980                         if idx != route.hops.len() - 1 && hop.pubkey == our_node_id {
 981                                 return Err(APIError::RouteError{err: "Route went through us but wasn't a simple rebalance loop to us"});
 982                         }
 983                 }
 984
 985                 let session_priv = self.keys_manager.get_session_key();
 986
 987                 let cur_height = self.latest_block_height.load(Ordering::Acquire) as u32 + 1;
 988
 989                 let onion_keys = secp_call!(onion_utils::construct_onion_keys(&self.secp_ctx, &route, &session_priv),
 990                                 APIError::RouteError{err: "Pubkey along hop was maliciously selected"});
 991                 let (onion_payloads, htlc_msat, htlc_cltv) = onion_utils::build_onion_payloads(&route, cur_height)?;
 992                 let onion_packet = onion_utils::construct_onion_packet(onion_payloads, onion_keys, &payment_hash);
 993
 994                 let _ = self.total_consistency_lock.read().unwrap();
 995
 996                 let err: Result<(), _> = loop {
 997                         let mut channel_lock = self.channel_state.lock().unwrap();
 998
 999                         let id = match channel_lock.short_to_id.get(&route.hops.first().unwrap().short_channel_id) {
1000                                 None => return Err(APIError::ChannelUnavailable{err: "No channel available with first hop!"}),
1001                                 Some(id) => id.clone(),
1002                         };
1003
1004                         let channel_state = channel_lock.borrow_parts();
1005                         if let hash_map::Entry::Occupied(mut chan) = channel_state.by_id.entry(id) {
1006                                 match {
1007                                         if chan.get().get_their_node_id() != route.hops.first().unwrap().pubkey {
1008                                                 return Err(APIError::RouteError{err: "Node ID mismatch on first hop!"});
1009                                         }
1010                                         if !chan.get().is_live() {
1011                                                 return Err(APIError::ChannelUnavailable{err: "Peer for first hop currently disconnected/pending monitor update!"});
1012                                         }
1013                                         break_chan_entry!(self, chan.get_mut().send_htlc_and_commit(htlc_msat, payment_hash.clone(), htlc_cltv, HTLCSource::OutboundRoute {
1014                                                 route: route.clone(),
1015                                                 session_priv: session_priv.clone(),
1016                                                 first_hop_htlc_msat: htlc_msat,
1017                                         }, onion_packet), channel_state, chan)
1018                                 } {
1019                                         Some((update_add, commitment_signed, chan_monitor)) => {
1020                                                 if let Err(e) = self.monitor.add_update_monitor(chan_monitor.get_funding_txo().unwrap(), chan_monitor) {
1021                                                         maybe_break_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::CommitmentFirst);
1022                                                         // Note that MonitorUpdateFailed here indicates (per function docs)
1023                                                         // that we will resent the commitment update once we unfree monitor
1024                                                         // updating, so we have to take special care that we don't return
1025                                                         // something else in case we will resend later!
1026                                                         return Err(APIError::MonitorUpdateFailed);
1027                                                 }
1028
1029                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
1030                                                         node_id: route.hops.first().unwrap().pubkey,
1031                                                         updates: msgs::CommitmentUpdate {
1032                                                                 update_add_htlcs: vec![update_add],
1033                                                                 update_fulfill_htlcs: Vec::new(),
1034                                                                 update_fail_htlcs: Vec::new(),
1035                                                                 update_fail_malformed_htlcs: Vec::new(),
1036                                                                 update_fee: None,
1037                                                                 commitment_signed,
1038                                                         },
1039                                                 });
1040                                         },
1041                                         None => {},
1042                                 }
1043                         } else { unreachable!(); }
1044                         return Ok(());
1045                 };
1046
1047                 match handle_error!(self, err, route.hops.first().unwrap().pubkey) {
1048                         Ok(_) => unreachable!(),
1049                         Err(e) => {
1050                                 if let Some(msgs::ErrorAction::IgnoreError) = e.action {
1051                                 } else {
1052                                         log_error!(self, "Got bad keys: {}!", e.err);
1053                                         let mut channel_state = self.channel_state.lock().unwrap();
1054                                         channel_state.pending_msg_events.push(events::MessageSendEvent::HandleError {
1055                                                 node_id: route.hops.first().unwrap().pubkey,
1056                                                 action: e.action,
1057                                         });
1058                                 }
1059                                 Err(APIError::ChannelUnavailable { err: e.err })
1060                         },
1061                 }
1062         }
1063
1064         /// Call this upon creation of a funding transaction for the given channel.
1065         ///
1066         /// Note that ALL inputs in the transaction pointed to by funding_txo MUST spend SegWit outputs
1067         /// or your counterparty can steal your funds!
1068         ///
1069         /// Panics if a funding transaction has already been provided for this channel.
1070         ///
1071         /// May panic if the funding_txo is duplicative with some other channel (note that this should
1072         /// be trivially prevented by using unique funding transaction keys per-channel).
1073         pub fn funding_transaction_generated(&self, temporary_channel_id: &[u8; 32], funding_txo: OutPoint) {
1074                 let _ = self.total_consistency_lock.read().unwrap();
1075
1076                 let (chan, msg, chan_monitor) = {
1077                         let (res, chan) = {
1078                                 let mut channel_state = self.channel_state.lock().unwrap();
1079                                 match channel_state.by_id.remove(temporary_channel_id) {
1080                                         Some(mut chan) => {
1081                                                 (chan.get_outbound_funding_created(funding_txo)
1082                                                         .map_err(|e| if let ChannelError::Close(msg) = e {
1083                                                                 MsgHandleErrInternal::from_finish_shutdown(msg, chan.channel_id(), chan.force_shutdown(), None)
1084                                                         } else { unreachable!(); })
1085                                                 , chan)
1086                                         },
1087                                         None => return
1088                                 }
1089                         };
1090                         match handle_error!(self, res, chan.get_their_node_id()) {
1091                                 Ok(funding_msg) => {
1092                                         (chan, funding_msg.0, funding_msg.1)
1093                                 },
1094                                 Err(e) => {
1095                                         log_error!(self, "Got bad signatures: {}!", e.err);
1096                                         let mut channel_state = self.channel_state.lock().unwrap();
1097                                         channel_state.pending_msg_events.push(events::MessageSendEvent::HandleError {
1098                                                 node_id: chan.get_their_node_id(),
1099                                                 action: e.action,
1100                                         });
1101                                         return;
1102                                 },
1103                         }
1104                 };
1105                 // Because we have exclusive ownership of the channel here we can release the channel_state
1106                 // lock before add_update_monitor
1107                 if let Err(_e) = self.monitor.add_update_monitor(chan_monitor.get_funding_txo().unwrap(), chan_monitor) {
1108                         unimplemented!();
1109                 }
1110
1111                 let mut channel_state = self.channel_state.lock().unwrap();
1112                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendFundingCreated {
1113                         node_id: chan.get_their_node_id(),
1114                         msg: msg,
1115                 });
1116                 match channel_state.by_id.entry(chan.channel_id()) {
1117                         hash_map::Entry::Occupied(_) => {
1118                                 panic!("Generated duplicate funding txid?");
1119                         },
1120                         hash_map::Entry::Vacant(e) => {
1121                                 e.insert(chan);
1122                         }
1123                 }
1124         }
1125
1126         fn get_announcement_sigs(&self, chan: &Channel) -> Option<msgs::AnnouncementSignatures> {
1127                 if !chan.should_announce() { return None }
1128
1129                 let (announcement, our_bitcoin_sig) = match chan.get_channel_announcement(self.get_our_node_id(), self.genesis_hash.clone()) {
1130                         Ok(res) => res,
1131                         Err(_) => return None, // Only in case of state precondition violations eg channel is closing
1132                 };
1133                 let msghash = Message::from_slice(&Sha256dHash::from_data(&announcement.encode()[..])[..]).unwrap();
1134                 let our_node_sig = self.secp_ctx.sign(&msghash, &self.our_network_key);
1135
1136                 Some(msgs::AnnouncementSignatures {
1137                         channel_id: chan.channel_id(),
1138                         short_channel_id: chan.get_short_channel_id().unwrap(),
1139                         node_signature: our_node_sig,
1140                         bitcoin_signature: our_bitcoin_sig,
1141                 })
1142         }
1143
1144         /// Processes HTLCs which are pending waiting on random forward delay.
1145         ///
1146         /// Should only really ever be called in response to an PendingHTLCsForwardable event.
1147         /// Will likely generate further events.
1148         pub fn process_pending_htlc_forwards(&self) {
1149                 let _ = self.total_consistency_lock.read().unwrap();
1150
1151                 let mut new_events = Vec::new();
1152                 let mut failed_forwards = Vec::new();
1153                 {
1154                         let mut channel_state_lock = self.channel_state.lock().unwrap();
1155                         let channel_state = channel_state_lock.borrow_parts();
1156
1157                         if cfg!(not(feature = "fuzztarget")) && Instant::now() < *channel_state.next_forward {
1158                                 return;
1159                         }
1160
1161                         for (short_chan_id, mut pending_forwards) in channel_state.forward_htlcs.drain() {
1162                                 if short_chan_id != 0 {
1163                                         let forward_chan_id = match channel_state.short_to_id.get(&short_chan_id) {
1164                                                 Some(chan_id) => chan_id.clone(),
1165                                                 None => {
1166                                                         failed_forwards.reserve(pending_forwards.len());
1167                                                         for forward_info in pending_forwards.drain(..) {
1168                                                                 match forward_info {
1169                                                                         HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info } => {
1170                                                                                 let htlc_source = HTLCSource::PreviousHopData(HTLCPreviousHopData {
1171                                                                                         short_channel_id: prev_short_channel_id,
1172                                                                                         htlc_id: prev_htlc_id,
1173                                                                                         incoming_packet_shared_secret: forward_info.incoming_shared_secret,
1174                                                                                 });
1175                                                                                 failed_forwards.push((htlc_source, forward_info.payment_hash, 0x4000 | 10, None));
1176                                                                         },
1177                                                                         HTLCForwardInfo::FailHTLC { .. } => {
1178                                                                                 // Channel went away before we could fail it. This implies
1179                                                                                 // the channel is now on chain and our counterparty is
1180                                                                                 // trying to broadcast the HTLC-Timeout, but that's their
1181                                                                                 // problem, not ours.
1182                                                                         }
1183                                                                 }
1184                                                         }
1185                                                         continue;
1186                                                 }
1187                                         };
1188                                         let forward_chan = &mut channel_state.by_id.get_mut(&forward_chan_id).unwrap();
1189
1190                                         let mut add_htlc_msgs = Vec::new();
1191                                         let mut fail_htlc_msgs = Vec::new();
1192                                         for forward_info in pending_forwards.drain(..) {
1193                                                 match forward_info {
1194                                                         HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info } => {
1195                                                                 log_trace!(self, "Adding HTLC from short id {} with payment_hash {} to channel with short id {} after delay", log_bytes!(forward_info.payment_hash.0), prev_short_channel_id, short_chan_id);
1196                                                                 let htlc_source = HTLCSource::PreviousHopData(HTLCPreviousHopData {
1197                                                                         short_channel_id: prev_short_channel_id,
1198                                                                         htlc_id: prev_htlc_id,
1199                                                                         incoming_packet_shared_secret: forward_info.incoming_shared_secret,
1200                                                                 });
1201                                                                 match forward_chan.send_htlc(forward_info.amt_to_forward, forward_info.payment_hash, forward_info.outgoing_cltv_value, htlc_source.clone(), forward_info.onion_packet.unwrap()) {
1202                                                                         Err(e) => {
1203                                                                                 if let ChannelError::Ignore(_) = e {} else {
1204                                                                                         panic!("Stated return value requirements in send_htlc() were not met");
1205                                                                                 }
1206                                                                                 let chan_update = self.get_channel_update(forward_chan).unwrap();
1207                                                                                 failed_forwards.push((htlc_source, forward_info.payment_hash, 0x1000 | 7, Some(chan_update)));
1208                                                                                 continue;
1209                                                                         },
1210                                                                         Ok(update_add) => {
1211                                                                                 match update_add {
1212                                                                                         Some(msg) => { add_htlc_msgs.push(msg); },
1213                                                                                         None => {
1214                                                                                                 // Nothing to do here...we're waiting on a remote
1215                                                                                                 // revoke_and_ack before we can add anymore HTLCs. The Channel
1216                                                                                                 // will automatically handle building the update_add_htlc and
1217                                                                                                 // commitment_signed messages when we can.
1218                                                                                                 // TODO: Do some kind of timer to set the channel as !is_live()
1219                                                                                                 // as we don't really want others relying on us relaying through
1220                                                                                                 // this channel currently :/.
1221                                                                                         }
1222                                                                                 }
1223                                                                         }
1224                                                                 }
1225                                                         },
1226                                                         HTLCForwardInfo::FailHTLC { htlc_id, err_packet } => {
1227                                                                 log_trace!(self, "Failing HTLC back to channel with short id {} after delay", short_chan_id);
1228                                                                 match forward_chan.get_update_fail_htlc(htlc_id, err_packet) {
1229                                                                         Err(e) => {
1230                                                                                 if let ChannelError::Ignore(_) = e {} else {
1231                                                                                         panic!("Stated return value requirements in get_update_fail_htlc() were not met");
1232                                                                                 }
1233                                                                                 // fail-backs are best-effort, we probably already have one
1234                                                                                 // pending, and if not that's OK, if not, the channel is on
1235                                                                                 // the chain and sending the HTLC-Timeout is their problem.
1236                                                                                 continue;
1237                                                                         },
1238                                                                         Ok(Some(msg)) => { fail_htlc_msgs.push(msg); },
1239                                                                         Ok(None) => {
1240                                                                                 // Nothing to do here...we're waiting on a remote
1241                                                                                 // revoke_and_ack before we can update the commitment
1242                                                                                 // transaction. The Channel will automatically handle
1243                                                                                 // building the update_fail_htlc and commitment_signed
1244                                                                                 // messages when we can.
1245                                                                                 // We don't need any kind of timer here as they should fail
1246                                                                                 // the channel onto the chain if they can't get our
1247                                                                                 // update_fail_htlc in time, its not our problem.
1248                                                                         }
1249                                                                 }
1250                                                         },
1251                                                 }
1252                                         }
1253
1254                                         if !add_htlc_msgs.is_empty() || !fail_htlc_msgs.is_empty() {
1255                                                 let (commitment_msg, monitor) = match forward_chan.send_commitment() {
1256                                                         Ok(res) => res,
1257                                                         Err(e) => {
1258                                                                 if let ChannelError::Ignore(_) = e {
1259                                                                         panic!("Stated return value requirements in send_commitment() were not met");
1260                                                                 }
1261                                                                 //TODO: Handle...this is bad!
1262                                                                 continue;
1263                                                         },
1264                                                 };
1265                                                 if let Err(_e) = self.monitor.add_update_monitor(monitor.get_funding_txo().unwrap(), monitor) {
1266                                                         unimplemented!();
1267                                                 }
1268                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
1269                                                         node_id: forward_chan.get_their_node_id(),
1270                                                         updates: msgs::CommitmentUpdate {
1271                                                                 update_add_htlcs: add_htlc_msgs,
1272                                                                 update_fulfill_htlcs: Vec::new(),
1273                                                                 update_fail_htlcs: fail_htlc_msgs,
1274                                                                 update_fail_malformed_htlcs: Vec::new(),
1275                                                                 update_fee: None,
1276                                                                 commitment_signed: commitment_msg,
1277                                                         },
1278                                                 });
1279                                         }
1280                                 } else {
1281                                         for forward_info in pending_forwards.drain(..) {
1282                                                 match forward_info {
1283                                                         HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info } => {
1284                                                                 let prev_hop_data = HTLCPreviousHopData {
1285                                                                         short_channel_id: prev_short_channel_id,
1286                                                                         htlc_id: prev_htlc_id,
1287                                                                         incoming_packet_shared_secret: forward_info.incoming_shared_secret,
1288                                                                 };
1289                                                                 match channel_state.claimable_htlcs.entry(forward_info.payment_hash) {
1290                                                                         hash_map::Entry::Occupied(mut entry) => entry.get_mut().push(prev_hop_data),
1291                                                                         hash_map::Entry::Vacant(entry) => { entry.insert(vec![prev_hop_data]); },
1292                                                                 };
1293                                                                 new_events.push(events::Event::PaymentReceived {
1294                                                                         payment_hash: forward_info.payment_hash,
1295                                                                         amt: forward_info.amt_to_forward,
1296                                                                 });
1297                                                         },
1298                                                         HTLCForwardInfo::FailHTLC { .. } => {
1299                                                                 panic!("Got pending fail of our own HTLC");
1300                                                         }
1301                                                 }
1302                                         }
1303                                 }
1304                         }
1305                 }
1306
1307                 for (htlc_source, payment_hash, failure_code, update) in failed_forwards.drain(..) {
1308                         match update {
1309                                 None => self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), htlc_source, &payment_hash, HTLCFailReason::Reason { failure_code, data: Vec::new() }),
1310                                 Some(chan_update) => self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), htlc_source, &payment_hash, HTLCFailReason::Reason { failure_code, data: chan_update.encode_with_len() }),
1311                         };
1312                 }
1313
1314                 if new_events.is_empty() { return }
1315                 let mut events = self.pending_events.lock().unwrap();
1316                 events.append(&mut new_events);
1317         }
1318
1319         /// Indicates that the preimage for payment_hash is unknown or the received amount is incorrect
1320         /// after a PaymentReceived event.
1321         /// expected_value is the value you expected the payment to be for (not the amount it actually
1322         /// was for from the PaymentReceived event).
1323         pub fn fail_htlc_backwards(&self, payment_hash: &PaymentHash, expected_value: u64) -> bool {
1324                 let _ = self.total_consistency_lock.read().unwrap();
1325
1326                 let mut channel_state = Some(self.channel_state.lock().unwrap());
1327                 let removed_source = channel_state.as_mut().unwrap().claimable_htlcs.remove(payment_hash);
1328                 if let Some(mut sources) = removed_source {
1329                         for htlc_with_hash in sources.drain(..) {
1330                                 if channel_state.is_none() { channel_state = Some(self.channel_state.lock().unwrap()); }
1331                                 self.fail_htlc_backwards_internal(channel_state.take().unwrap(),
1332                                                 HTLCSource::PreviousHopData(htlc_with_hash), payment_hash,
1333                                                 HTLCFailReason::Reason { failure_code: 0x4000 | 15, data: byte_utils::be64_to_array(expected_value).to_vec() });
1334                         }
1335                         true
1336                 } else { false }
1337         }
1338
1339         /// Fails an HTLC backwards to the sender of it to us.
1340         /// Note that while we take a channel_state lock as input, we do *not* assume consistency here.
1341         /// There are several callsites that do stupid things like loop over a list of payment_hashes
1342         /// to fail and take the channel_state lock for each iteration (as we take ownership and may
1343         /// drop it). In other words, no assumptions are made that entries in claimable_htlcs point to
1344         /// still-available channels.
1345         fn fail_htlc_backwards_internal(&self, mut channel_state_lock: MutexGuard<ChannelHolder>, source: HTLCSource, payment_hash: &PaymentHash, onion_error: HTLCFailReason) {
1346                 //TODO: There is a timing attack here where if a node fails an HTLC back to us they can
1347                 //identify whether we sent it or not based on the (I presume) very different runtime
1348                 //between the branches here. We should make this async and move it into the forward HTLCs
1349                 //timer handling.
1350                 match source {
1351                         HTLCSource::OutboundRoute { ref route, .. } => {
1352                                 log_trace!(self, "Failing outbound payment HTLC with payment_hash {}", log_bytes!(payment_hash.0));
1353                                 mem::drop(channel_state_lock);
1354                                 match &onion_error {
1355                                         &HTLCFailReason::ErrorPacket { ref err } => {
1356 #[cfg(test)]
1357                                                 let (channel_update, payment_retryable, onion_error_code) = onion_utils::process_onion_failure(&self.secp_ctx, &self.logger, &source, err.data.clone());
1358 #[cfg(not(test))]
1359                                                 let (channel_update, payment_retryable, _) = onion_utils::process_onion_failure(&self.secp_ctx, &self.logger, &source, err.data.clone());
1360                                                 // TODO: If we decided to blame ourselves (or one of our channels) in
1361                                                 // process_onion_failure we should close that channel as it implies our
1362                                                 // next-hop is needlessly blaming us!
1363                                                 if let Some(update) = channel_update {
1364                                                         self.channel_state.lock().unwrap().pending_msg_events.push(
1365                                                                 events::MessageSendEvent::PaymentFailureNetworkUpdate {
1366                                                                         update,
1367                                                                 }
1368                                                         );
1369                                                 }
1370                                                 self.pending_events.lock().unwrap().push(
1371                                                         events::Event::PaymentFailed {
1372                                                                 payment_hash: payment_hash.clone(),
1373                                                                 rejected_by_dest: !payment_retryable,
1374 #[cfg(test)]
1375                                                                 error_code: onion_error_code
1376                                                         }
1377                                                 );
1378                                         },
1379                                         &HTLCFailReason::Reason {
1380 #[cfg(test)]
1381                                                         ref failure_code,
1382                                                         .. } => {
1383                                                 // we get a fail_malformed_htlc from the first hop
1384                                                 // TODO: We'd like to generate a PaymentFailureNetworkUpdate for temporary
1385                                                 // failures here, but that would be insufficient as Router::get_route
1386                                                 // generally ignores its view of our own channels as we provide them via
1387                                                 // ChannelDetails.
1388                                                 // TODO: For non-temporary failures, we really should be closing the
1389                                                 // channel here as we apparently can't relay through them anyway.
1390                                                 self.pending_events.lock().unwrap().push(
1391                                                         events::Event::PaymentFailed {
1392                                                                 payment_hash: payment_hash.clone(),
1393                                                                 rejected_by_dest: route.hops.len() == 1,
1394 #[cfg(test)]
1395                                                                 error_code: Some(*failure_code),
1396                                                         }
1397                                                 );
1398                                         }
1399                                 }
1400                         },
1401                         HTLCSource::PreviousHopData(HTLCPreviousHopData { short_channel_id, htlc_id, incoming_packet_shared_secret }) => {
1402                                 let err_packet = match onion_error {
1403                                         HTLCFailReason::Reason { failure_code, data } => {
1404                                                 log_trace!(self, "Failing HTLC with payment_hash {} backwards from us with code {}", log_bytes!(payment_hash.0), failure_code);
1405                                                 let packet = onion_utils::build_failure_packet(&incoming_packet_shared_secret, failure_code, &data[..]).encode();
1406                                                 onion_utils::encrypt_failure_packet(&incoming_packet_shared_secret, &packet)
1407                                         },
1408                                         HTLCFailReason::ErrorPacket { err } => {
1409                                                 log_trace!(self, "Failing HTLC with payment_hash {} backwards with pre-built ErrorPacket", log_bytes!(payment_hash.0));
1410                                                 onion_utils::encrypt_failure_packet(&incoming_packet_shared_secret, &err.data)
1411                                         }
1412                                 };
1413
1414                                 let mut forward_event = None;
1415                                 if channel_state_lock.forward_htlcs.is_empty() {
1416                                         forward_event = Some(Instant::now() + Duration::from_millis(((rng::rand_f32() * 4.0 + 1.0) * MIN_HTLC_RELAY_HOLDING_CELL_MILLIS as f32) as u64));
1417                                         channel_state_lock.next_forward = forward_event.unwrap();
1418                                 }
1419                                 match channel_state_lock.forward_htlcs.entry(short_channel_id) {
1420                                         hash_map::Entry::Occupied(mut entry) => {
1421                                                 entry.get_mut().push(HTLCForwardInfo::FailHTLC { htlc_id, err_packet });
1422                                         },
1423                                         hash_map::Entry::Vacant(entry) => {
1424                                                 entry.insert(vec!(HTLCForwardInfo::FailHTLC { htlc_id, err_packet }));
1425                                         }
1426                                 }
1427                                 mem::drop(channel_state_lock);
1428                                 if let Some(time) = forward_event {
1429                                         let mut pending_events = self.pending_events.lock().unwrap();
1430                                         pending_events.push(events::Event::PendingHTLCsForwardable {
1431                                                 time_forwardable: time
1432                                         });
1433                                 }
1434                         },
1435                 }
1436         }
1437
1438         /// Provides a payment preimage in response to a PaymentReceived event, returning true and
1439         /// generating message events for the net layer to claim the payment, if possible. Thus, you
1440         /// should probably kick the net layer to go send messages if this returns true!
1441         ///
1442         /// May panic if called except in response to a PaymentReceived event.
1443         pub fn claim_funds(&self, payment_preimage: PaymentPreimage) -> bool {
1444                 let payment_hash = PaymentHash(Sha256::hash(&payment_preimage.0).into_inner());
1445
1446                 let _ = self.total_consistency_lock.read().unwrap();
1447
1448                 let mut channel_state = Some(self.channel_state.lock().unwrap());
1449                 let removed_source = channel_state.as_mut().unwrap().claimable_htlcs.remove(&payment_hash);
1450                 if let Some(mut sources) = removed_source {
1451                         for htlc_with_hash in sources.drain(..) {
1452                                 if channel_state.is_none() { channel_state = Some(self.channel_state.lock().unwrap()); }
1453                                 self.claim_funds_internal(channel_state.take().unwrap(), HTLCSource::PreviousHopData(htlc_with_hash), payment_preimage);
1454                         }
1455                         true
1456                 } else { false }
1457         }
1458         fn claim_funds_internal(&self, mut channel_state_lock: MutexGuard<ChannelHolder>, source: HTLCSource, payment_preimage: PaymentPreimage) {
1459                 match source {
1460                         HTLCSource::OutboundRoute { .. } => {
1461                                 mem::drop(channel_state_lock);
1462                                 let mut pending_events = self.pending_events.lock().unwrap();
1463                                 pending_events.push(events::Event::PaymentSent {
1464                                         payment_preimage
1465                                 });
1466                         },
1467                         HTLCSource::PreviousHopData(HTLCPreviousHopData { short_channel_id, htlc_id, .. }) => {
1468                                 //TODO: Delay the claimed_funds relaying just like we do outbound relay!
1469                                 let channel_state = channel_state_lock.borrow_parts();
1470
1471                                 let chan_id = match channel_state.short_to_id.get(&short_channel_id) {
1472                                         Some(chan_id) => chan_id.clone(),
1473                                         None => {
1474                                                 // TODO: There is probably a channel manager somewhere that needs to
1475                                                 // learn the preimage as the channel already hit the chain and that's
1476                                                 // why its missing.
1477                                                 return
1478                                         }
1479                                 };
1480
1481                                 let chan = channel_state.by_id.get_mut(&chan_id).unwrap();
1482                                 match chan.get_update_fulfill_htlc_and_commit(htlc_id, payment_preimage) {
1483                                         Ok((msgs, monitor_option)) => {
1484                                                 if let Some(chan_monitor) = monitor_option {
1485                                                         if let Err(_e) = self.monitor.add_update_monitor(chan_monitor.get_funding_txo().unwrap(), chan_monitor) {
1486                                                                 unimplemented!();// but def dont push the event...
1487                                                         }
1488                                                 }
1489                                                 if let Some((msg, commitment_signed)) = msgs {
1490                                                         channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
1491                                                                 node_id: chan.get_their_node_id(),
1492                                                                 updates: msgs::CommitmentUpdate {
1493                                                                         update_add_htlcs: Vec::new(),
1494                                                                         update_fulfill_htlcs: vec![msg],
1495                                                                         update_fail_htlcs: Vec::new(),
1496                                                                         update_fail_malformed_htlcs: Vec::new(),
1497                                                                         update_fee: None,
1498                                                                         commitment_signed,
1499                                                                 }
1500                                                         });
1501                                                 }
1502                                         },
1503                                         Err(_e) => {
1504                                                 // TODO: There is probably a channel manager somewhere that needs to
1505                                                 // learn the preimage as the channel may be about to hit the chain.
1506                                                 //TODO: Do something with e?
1507                                                 return
1508                                         },
1509                                 }
1510                         },
1511                 }
1512         }
1513
1514         /// Gets the node_id held by this ChannelManager
1515         pub fn get_our_node_id(&self) -> PublicKey {
1516                 PublicKey::from_secret_key(&self.secp_ctx, &self.our_network_key)
1517         }
1518
1519         /// Used to restore channels to normal operation after a
1520         /// ChannelMonitorUpdateErr::TemporaryFailure was returned from a channel monitor update
1521         /// operation.
1522         pub fn test_restore_channel_monitor(&self) {
1523                 let mut close_results = Vec::new();
1524                 let mut htlc_forwards = Vec::new();
1525                 let mut htlc_failures = Vec::new();
1526                 let _ = self.total_consistency_lock.read().unwrap();
1527
1528                 {
1529                         let mut channel_lock = self.channel_state.lock().unwrap();
1530                         let channel_state = channel_lock.borrow_parts();
1531                         let short_to_id = channel_state.short_to_id;
1532                         let pending_msg_events = channel_state.pending_msg_events;
1533                         channel_state.by_id.retain(|_, channel| {
1534                                 if channel.is_awaiting_monitor_update() {
1535                                         let chan_monitor = channel.channel_monitor();
1536                                         if let Err(e) = self.monitor.add_update_monitor(chan_monitor.get_funding_txo().unwrap(), chan_monitor) {
1537                                                 match e {
1538                                                         ChannelMonitorUpdateErr::PermanentFailure => {
1539                                                                 // TODO: There may be some pending HTLCs that we intended to fail
1540                                                                 // backwards when a monitor update failed. We should make sure
1541                                                                 // knowledge of those gets moved into the appropriate in-memory
1542                                                                 // ChannelMonitor and they get failed backwards once we get
1543                                                                 // on-chain confirmations.
1544                                                                 // Note I think #198 addresses this, so once its merged a test
1545                                                                 // should be written.
1546                                                                 if let Some(short_id) = channel.get_short_channel_id() {
1547                                                                         short_to_id.remove(&short_id);
1548                                                                 }
1549                                                                 close_results.push(channel.force_shutdown());
1550                                                                 if let Ok(update) = self.get_channel_update(&channel) {
1551                                                                         pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
1552                                                                                 msg: update
1553                                                                         });
1554                                                                 }
1555                                                                 false
1556                                                         },
1557                                                         ChannelMonitorUpdateErr::TemporaryFailure => true,
1558                                                 }
1559                                         } else {
1560                                                 let (raa, commitment_update, order, pending_forwards, mut pending_failures) = channel.monitor_updating_restored();
1561                                                 if !pending_forwards.is_empty() {
1562                                                         htlc_forwards.push((channel.get_short_channel_id().expect("We can't have pending forwards before funding confirmation"), pending_forwards));
1563                                                 }
1564                                                 htlc_failures.append(&mut pending_failures);
1565
1566                                                 macro_rules! handle_cs { () => {
1567                                                         if let Some(update) = commitment_update {
1568                                                                 pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
1569                                                                         node_id: channel.get_their_node_id(),
1570                                                                         updates: update,
1571                                                                 });
1572                                                         }
1573                                                 } }
1574                                                 macro_rules! handle_raa { () => {
1575                                                         if let Some(revoke_and_ack) = raa {
1576                                                                 pending_msg_events.push(events::MessageSendEvent::SendRevokeAndACK {
1577                                                                         node_id: channel.get_their_node_id(),
1578                                                                         msg: revoke_and_ack,
1579                                                                 });
1580                                                         }
1581                                                 } }
1582                                                 match order {
1583                                                         RAACommitmentOrder::CommitmentFirst => {
1584                                                                 handle_cs!();
1585                                                                 handle_raa!();
1586                                                         },
1587                                                         RAACommitmentOrder::RevokeAndACKFirst => {
1588                                                                 handle_raa!();
1589                                                                 handle_cs!();
1590                                                         },
1591                                                 }
1592                                                 true
1593                                         }
1594                                 } else { true }
1595                         });
1596                 }
1597
1598                 for failure in htlc_failures.drain(..) {
1599                         self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), failure.0, &failure.1, failure.2);
1600                 }
1601                 self.forward_htlcs(&mut htlc_forwards[..]);
1602
1603                 for res in close_results.drain(..) {
1604                         self.finish_force_close_channel(res);
1605                 }
1606         }
1607
1608         fn internal_open_channel(&self, their_node_id: &PublicKey, msg: &msgs::OpenChannel) -> Result<(), MsgHandleErrInternal> {
1609                 if msg.chain_hash != self.genesis_hash {
1610                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Unknown genesis block hash", msg.temporary_channel_id.clone()));
1611                 }
1612
1613                 let channel = Channel::new_from_req(&*self.fee_estimator, &self.keys_manager, their_node_id.clone(), msg, 0, Arc::clone(&self.logger), &self.default_configuration)
1614                         .map_err(|e| MsgHandleErrInternal::from_chan_no_close(e, msg.temporary_channel_id))?;
1615                 let mut channel_state_lock = self.channel_state.lock().unwrap();
1616                 let channel_state = channel_state_lock.borrow_parts();
1617                 match channel_state.by_id.entry(channel.channel_id()) {
1618                         hash_map::Entry::Occupied(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("temporary_channel_id collision!", msg.temporary_channel_id.clone())),
1619                         hash_map::Entry::Vacant(entry) => {
1620                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendAcceptChannel {
1621                                         node_id: their_node_id.clone(),
1622                                         msg: channel.get_accept_channel(),
1623                                 });
1624                                 entry.insert(channel);
1625                         }
1626                 }
1627                 Ok(())
1628         }
1629
1630         fn internal_accept_channel(&self, their_node_id: &PublicKey, msg: &msgs::AcceptChannel) -> Result<(), MsgHandleErrInternal> {
1631                 let (value, output_script, user_id) = {
1632                         let mut channel_lock = self.channel_state.lock().unwrap();
1633                         let channel_state = channel_lock.borrow_parts();
1634                         match channel_state.by_id.entry(msg.temporary_channel_id) {
1635                                 hash_map::Entry::Occupied(mut chan) => {
1636                                         if chan.get().get_their_node_id() != *their_node_id {
1637                                                 //TODO: see issue #153, need a consistent behavior on obnoxious behavior from random node
1638                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.temporary_channel_id));
1639                                         }
1640                                         try_chan_entry!(self, chan.get_mut().accept_channel(&msg, &self.default_configuration), channel_state, chan);
1641                                         (chan.get().get_value_satoshis(), chan.get().get_funding_redeemscript().to_v0_p2wsh(), chan.get().get_user_id())
1642                                 },
1643                                 //TODO: same as above
1644                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.temporary_channel_id))
1645                         }
1646                 };
1647                 let mut pending_events = self.pending_events.lock().unwrap();
1648                 pending_events.push(events::Event::FundingGenerationReady {
1649                         temporary_channel_id: msg.temporary_channel_id,
1650                         channel_value_satoshis: value,
1651                         output_script: output_script,
1652                         user_channel_id: user_id,
1653                 });
1654                 Ok(())
1655         }
1656
1657         fn internal_funding_created(&self, their_node_id: &PublicKey, msg: &msgs::FundingCreated) -> Result<(), MsgHandleErrInternal> {
1658                 let ((funding_msg, monitor_update), chan) = {
1659                         let mut channel_lock = self.channel_state.lock().unwrap();
1660                         let channel_state = channel_lock.borrow_parts();
1661                         match channel_state.by_id.entry(msg.temporary_channel_id.clone()) {
1662                                 hash_map::Entry::Occupied(mut chan) => {
1663                                         if chan.get().get_their_node_id() != *their_node_id {
1664                                                 //TODO: here and below MsgHandleErrInternal, #153 case
1665                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.temporary_channel_id));
1666                                         }
1667                                         (try_chan_entry!(self, chan.get_mut().funding_created(msg), channel_state, chan), chan.remove())
1668                                 },
1669                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.temporary_channel_id))
1670                         }
1671                 };
1672                 // Because we have exclusive ownership of the channel here we can release the channel_state
1673                 // lock before add_update_monitor
1674                 if let Err(_e) = self.monitor.add_update_monitor(monitor_update.get_funding_txo().unwrap(), monitor_update) {
1675                         unimplemented!();
1676                 }
1677                 let mut channel_state_lock = self.channel_state.lock().unwrap();
1678                 let channel_state = channel_state_lock.borrow_parts();
1679                 match channel_state.by_id.entry(funding_msg.channel_id) {
1680                         hash_map::Entry::Occupied(_) => {
1681                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Already had channel with the new channel_id", funding_msg.channel_id))
1682                         },
1683                         hash_map::Entry::Vacant(e) => {
1684                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendFundingSigned {
1685                                         node_id: their_node_id.clone(),
1686                                         msg: funding_msg,
1687                                 });
1688                                 e.insert(chan);
1689                         }
1690                 }
1691                 Ok(())
1692         }
1693
1694         fn internal_funding_signed(&self, their_node_id: &PublicKey, msg: &msgs::FundingSigned) -> Result<(), MsgHandleErrInternal> {
1695                 let (funding_txo, user_id) = {
1696                         let mut channel_lock = self.channel_state.lock().unwrap();
1697                         let channel_state = channel_lock.borrow_parts();
1698                         match channel_state.by_id.entry(msg.channel_id) {
1699                                 hash_map::Entry::Occupied(mut chan) => {
1700                                         if chan.get().get_their_node_id() != *their_node_id {
1701                                                 //TODO: here and below MsgHandleErrInternal, #153 case
1702                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
1703                                         }
1704                                         let chan_monitor = try_chan_entry!(self, chan.get_mut().funding_signed(&msg), channel_state, chan);
1705                                         if let Err(_e) = self.monitor.add_update_monitor(chan_monitor.get_funding_txo().unwrap(), chan_monitor) {
1706                                                 unimplemented!();
1707                                         }
1708                                         (chan.get().get_funding_txo().unwrap(), chan.get().get_user_id())
1709                                 },
1710                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
1711                         }
1712                 };
1713                 let mut pending_events = self.pending_events.lock().unwrap();
1714                 pending_events.push(events::Event::FundingBroadcastSafe {
1715                         funding_txo: funding_txo,
1716                         user_channel_id: user_id,
1717                 });
1718                 Ok(())
1719         }
1720
1721         fn internal_funding_locked(&self, their_node_id: &PublicKey, msg: &msgs::FundingLocked) -> Result<(), MsgHandleErrInternal> {
1722                 let mut channel_state_lock = self.channel_state.lock().unwrap();
1723                 let channel_state = channel_state_lock.borrow_parts();
1724                 match channel_state.by_id.entry(msg.channel_id) {
1725                         hash_map::Entry::Occupied(mut chan) => {
1726                                 if chan.get().get_their_node_id() != *their_node_id {
1727                                         //TODO: here and below MsgHandleErrInternal, #153 case
1728                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
1729                                 }
1730                                 try_chan_entry!(self, chan.get_mut().funding_locked(&msg), channel_state, chan);
1731                                 if let Some(announcement_sigs) = self.get_announcement_sigs(chan.get()) {
1732                                         channel_state.pending_msg_events.push(events::MessageSendEvent::SendAnnouncementSignatures {
1733                                                 node_id: their_node_id.clone(),
1734                                                 msg: announcement_sigs,
1735                                         });
1736                                 }
1737                                 Ok(())
1738                         },
1739                         hash_map::Entry::Vacant(_) => Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
1740                 }
1741         }
1742
1743         fn internal_shutdown(&self, their_node_id: &PublicKey, msg: &msgs::Shutdown) -> Result<(), MsgHandleErrInternal> {
1744                 let (mut dropped_htlcs, chan_option) = {
1745                         let mut channel_state_lock = self.channel_state.lock().unwrap();
1746                         let channel_state = channel_state_lock.borrow_parts();
1747
1748                         match channel_state.by_id.entry(msg.channel_id.clone()) {
1749                                 hash_map::Entry::Occupied(mut chan_entry) => {
1750                                         if chan_entry.get().get_their_node_id() != *their_node_id {
1751                                                 //TODO: here and below MsgHandleErrInternal, #153 case
1752                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
1753                                         }
1754                                         let (shutdown, closing_signed, dropped_htlcs) = try_chan_entry!(self, chan_entry.get_mut().shutdown(&*self.fee_estimator, &msg), channel_state, chan_entry);
1755                                         if let Some(msg) = shutdown {
1756                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendShutdown {
1757                                                         node_id: their_node_id.clone(),
1758                                                         msg,
1759                                                 });
1760                                         }
1761                                         if let Some(msg) = closing_signed {
1762                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendClosingSigned {
1763                                                         node_id: their_node_id.clone(),
1764                                                         msg,
1765                                                 });
1766                                         }
1767                                         if chan_entry.get().is_shutdown() {
1768                                                 if let Some(short_id) = chan_entry.get().get_short_channel_id() {
1769                                                         channel_state.short_to_id.remove(&short_id);
1770                                                 }
1771                                                 (dropped_htlcs, Some(chan_entry.remove_entry().1))
1772                                         } else { (dropped_htlcs, None) }
1773                                 },
1774                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
1775                         }
1776                 };
1777                 for htlc_source in dropped_htlcs.drain(..) {
1778                         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() });
1779                 }
1780                 if let Some(chan) = chan_option {
1781                         if let Ok(update) = self.get_channel_update(&chan) {
1782                                 let mut channel_state = self.channel_state.lock().unwrap();
1783                                 channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
1784                                         msg: update
1785                                 });
1786                         }
1787                 }
1788                 Ok(())
1789         }
1790
1791         fn internal_closing_signed(&self, their_node_id: &PublicKey, msg: &msgs::ClosingSigned) -> Result<(), MsgHandleErrInternal> {
1792                 let (tx, chan_option) = {
1793                         let mut channel_state_lock = self.channel_state.lock().unwrap();
1794                         let channel_state = channel_state_lock.borrow_parts();
1795                         match channel_state.by_id.entry(msg.channel_id.clone()) {
1796                                 hash_map::Entry::Occupied(mut chan_entry) => {
1797                                         if chan_entry.get().get_their_node_id() != *their_node_id {
1798                                                 //TODO: here and below MsgHandleErrInternal, #153 case
1799                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
1800                                         }
1801                                         let (closing_signed, tx) = try_chan_entry!(self, chan_entry.get_mut().closing_signed(&*self.fee_estimator, &msg), channel_state, chan_entry);
1802                                         if let Some(msg) = closing_signed {
1803                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendClosingSigned {
1804                                                         node_id: their_node_id.clone(),
1805                                                         msg,
1806                                                 });
1807                                         }
1808                                         if tx.is_some() {
1809                                                 // We're done with this channel, we've got a signed closing transaction and
1810                                                 // will send the closing_signed back to the remote peer upon return. This
1811                                                 // also implies there are no pending HTLCs left on the channel, so we can
1812                                                 // fully delete it from tracking (the channel monitor is still around to
1813                                                 // watch for old state broadcasts)!
1814                                                 if let Some(short_id) = chan_entry.get().get_short_channel_id() {
1815                                                         channel_state.short_to_id.remove(&short_id);
1816                                                 }
1817                                                 (tx, Some(chan_entry.remove_entry().1))
1818                                         } else { (tx, None) }
1819                                 },
1820                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
1821                         }
1822                 };
1823                 if let Some(broadcast_tx) = tx {
1824                         self.tx_broadcaster.broadcast_transaction(&broadcast_tx);
1825                 }
1826                 if let Some(chan) = chan_option {
1827                         if let Ok(update) = self.get_channel_update(&chan) {
1828                                 let mut channel_state = self.channel_state.lock().unwrap();
1829                                 channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
1830                                         msg: update
1831                                 });
1832                         }
1833                 }
1834                 Ok(())
1835         }
1836
1837         fn internal_update_add_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateAddHTLC) -> Result<(), MsgHandleErrInternal> {
1838                 //TODO: BOLT 4 points out a specific attack where a peer may re-send an onion packet and
1839                 //determine the state of the payment based on our response/if we forward anything/the time
1840                 //we take to respond. We should take care to avoid allowing such an attack.
1841                 //
1842                 //TODO: There exists a further attack where a node may garble the onion data, forward it to
1843                 //us repeatedly garbled in different ways, and compare our error messages, which are
1844                 //encrypted with the same key. Its not immediately obvious how to usefully exploit that,
1845                 //but we should prevent it anyway.
1846
1847                 let (mut pending_forward_info, mut channel_state_lock) = self.decode_update_add_htlc_onion(msg);
1848                 let channel_state = channel_state_lock.borrow_parts();
1849
1850                 match channel_state.by_id.entry(msg.channel_id) {
1851                         hash_map::Entry::Occupied(mut chan) => {
1852                                 if chan.get().get_their_node_id() != *their_node_id {
1853                                         //TODO: here MsgHandleErrInternal, #153 case
1854                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
1855                                 }
1856                                 if !chan.get().is_usable() {
1857                                         // If the update_add is completely bogus, the call will Err and we will close,
1858                                         // but if we've sent a shutdown and they haven't acknowledged it yet, we just
1859                                         // want to reject the new HTLC and fail it backwards instead of forwarding.
1860                                         if let PendingHTLCStatus::Forward(PendingForwardHTLCInfo { incoming_shared_secret, .. }) = pending_forward_info {
1861                                                 let chan_update = self.get_channel_update(chan.get());
1862                                                 pending_forward_info = PendingHTLCStatus::Fail(HTLCFailureMsg::Relay(msgs::UpdateFailHTLC {
1863                                                         channel_id: msg.channel_id,
1864                                                         htlc_id: msg.htlc_id,
1865                                                         reason: if let Ok(update) = chan_update {
1866                                                                 // TODO: Note that |20 is defined as "channel FROM the processing
1867                                                                 // node has been disabled" (emphasis mine), which seems to imply
1868                                                                 // that we can't return |20 for an inbound channel being disabled.
1869                                                                 // This probably needs a spec update but should definitely be
1870                                                                 // allowed.
1871                                                                 onion_utils::build_first_hop_failure_packet(&incoming_shared_secret, 0x1000|20, &{
1872                                                                         let mut res = Vec::with_capacity(8 + 128);
1873                                                                         res.extend_from_slice(&byte_utils::be16_to_array(update.contents.flags));
1874                                                                         res.extend_from_slice(&update.encode_with_len()[..]);
1875                                                                         res
1876                                                                 }[..])
1877                                                         } else {
1878                                                                 // This can only happen if the channel isn't in the fully-funded
1879                                                                 // state yet, implying our counterparty is trying to route payments
1880                                                                 // over the channel back to themselves (cause no one else should
1881                                                                 // know the short_id is a lightning channel yet). We should have no
1882                                                                 // problem just calling this unknown_next_peer
1883                                                                 onion_utils::build_first_hop_failure_packet(&incoming_shared_secret, 0x4000|10, &[])
1884                                                         },
1885                                                 }));
1886                                         }
1887                                 }
1888                                 try_chan_entry!(self, chan.get_mut().update_add_htlc(&msg, pending_forward_info), channel_state, chan);
1889                         },
1890                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
1891                 }
1892                 Ok(())
1893         }
1894
1895         fn internal_update_fulfill_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFulfillHTLC) -> Result<(), MsgHandleErrInternal> {
1896                 let mut channel_lock = self.channel_state.lock().unwrap();
1897                 let htlc_source = {
1898                         let channel_state = channel_lock.borrow_parts();
1899                         match channel_state.by_id.entry(msg.channel_id) {
1900                                 hash_map::Entry::Occupied(mut chan) => {
1901                                         if chan.get().get_their_node_id() != *their_node_id {
1902                                                 //TODO: here and below MsgHandleErrInternal, #153 case
1903                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
1904                                         }
1905                                         try_chan_entry!(self, chan.get_mut().update_fulfill_htlc(&msg), channel_state, chan)
1906                                 },
1907                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
1908                         }
1909                 };
1910                 self.claim_funds_internal(channel_lock, htlc_source, msg.payment_preimage.clone());
1911                 Ok(())
1912         }
1913
1914         fn internal_update_fail_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFailHTLC) -> Result<(), MsgHandleErrInternal> {
1915                 let mut channel_lock = self.channel_state.lock().unwrap();
1916                 let channel_state = channel_lock.borrow_parts();
1917                 match channel_state.by_id.entry(msg.channel_id) {
1918                         hash_map::Entry::Occupied(mut chan) => {
1919                                 if chan.get().get_their_node_id() != *their_node_id {
1920                                         //TODO: here and below MsgHandleErrInternal, #153 case
1921                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
1922                                 }
1923                                 try_chan_entry!(self, chan.get_mut().update_fail_htlc(&msg, HTLCFailReason::ErrorPacket { err: msg.reason.clone() }), channel_state, chan);
1924                         },
1925                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
1926                 }
1927                 Ok(())
1928         }
1929
1930         fn internal_update_fail_malformed_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFailMalformedHTLC) -> Result<(), MsgHandleErrInternal> {
1931                 let mut channel_lock = self.channel_state.lock().unwrap();
1932                 let channel_state = channel_lock.borrow_parts();
1933                 match channel_state.by_id.entry(msg.channel_id) {
1934                         hash_map::Entry::Occupied(mut chan) => {
1935                                 if chan.get().get_their_node_id() != *their_node_id {
1936                                         //TODO: here and below MsgHandleErrInternal, #153 case
1937                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
1938                                 }
1939                                 if (msg.failure_code & 0x8000) == 0 {
1940                                         try_chan_entry!(self, Err(ChannelError::Close("Got update_fail_malformed_htlc with BADONION not set")), channel_state, chan);
1941                                 }
1942                                 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);
1943                                 Ok(())
1944                         },
1945                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
1946                 }
1947         }
1948
1949         fn internal_commitment_signed(&self, their_node_id: &PublicKey, msg: &msgs::CommitmentSigned) -> Result<(), MsgHandleErrInternal> {
1950                 let mut channel_state_lock = self.channel_state.lock().unwrap();
1951                 let channel_state = channel_state_lock.borrow_parts();
1952                 match channel_state.by_id.entry(msg.channel_id) {
1953                         hash_map::Entry::Occupied(mut chan) => {
1954                                 if chan.get().get_their_node_id() != *their_node_id {
1955                                         //TODO: here and below MsgHandleErrInternal, #153 case
1956                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
1957                                 }
1958                                 let (revoke_and_ack, commitment_signed, closing_signed, chan_monitor) =
1959                                         try_chan_entry!(self, chan.get_mut().commitment_signed(&msg, &*self.fee_estimator), channel_state, chan);
1960                                 if let Err(e) = self.monitor.add_update_monitor(chan_monitor.get_funding_txo().unwrap(), chan_monitor) {
1961                                         return_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::RevokeAndACKFirst, commitment_signed.is_some());
1962                                         //TODO: Rebroadcast closing_signed if present on monitor update restoration
1963                                 }
1964                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendRevokeAndACK {
1965                                         node_id: their_node_id.clone(),
1966                                         msg: revoke_and_ack,
1967                                 });
1968                                 if let Some(msg) = commitment_signed {
1969                                         channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
1970                                                 node_id: their_node_id.clone(),
1971                                                 updates: msgs::CommitmentUpdate {
1972                                                         update_add_htlcs: Vec::new(),
1973                                                         update_fulfill_htlcs: Vec::new(),
1974                                                         update_fail_htlcs: Vec::new(),
1975                                                         update_fail_malformed_htlcs: Vec::new(),
1976                                                         update_fee: None,
1977                                                         commitment_signed: msg,
1978                                                 },
1979                                         });
1980                                 }
1981                                 if let Some(msg) = closing_signed {
1982                                         channel_state.pending_msg_events.push(events::MessageSendEvent::SendClosingSigned {
1983                                                 node_id: their_node_id.clone(),
1984                                                 msg,
1985                                         });
1986                                 }
1987                                 Ok(())
1988                         },
1989                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
1990                 }
1991         }
1992
1993         #[inline]
1994         fn forward_htlcs(&self, per_source_pending_forwards: &mut [(u64, Vec<(PendingForwardHTLCInfo, u64)>)]) {
1995                 for &mut (prev_short_channel_id, ref mut pending_forwards) in per_source_pending_forwards {
1996                         let mut forward_event = None;
1997                         if !pending_forwards.is_empty() {
1998                                 let mut channel_state = self.channel_state.lock().unwrap();
1999                                 if channel_state.forward_htlcs.is_empty() {
2000                                         forward_event = Some(Instant::now() + Duration::from_millis(((rng::rand_f32() * 4.0 + 1.0) * MIN_HTLC_RELAY_HOLDING_CELL_MILLIS as f32) as u64));
2001                                         channel_state.next_forward = forward_event.unwrap();
2002                                 }
2003                                 for (forward_info, prev_htlc_id) in pending_forwards.drain(..) {
2004                                         match channel_state.forward_htlcs.entry(forward_info.short_channel_id) {
2005                                                 hash_map::Entry::Occupied(mut entry) => {
2006                                                         entry.get_mut().push(HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info });
2007                                                 },
2008                                                 hash_map::Entry::Vacant(entry) => {
2009                                                         entry.insert(vec!(HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info }));
2010                                                 }
2011                                         }
2012                                 }
2013                         }
2014                         match forward_event {
2015                                 Some(time) => {
2016                                         let mut pending_events = self.pending_events.lock().unwrap();
2017                                         pending_events.push(events::Event::PendingHTLCsForwardable {
2018                                                 time_forwardable: time
2019                                         });
2020                                 }
2021                                 None => {},
2022                         }
2023                 }
2024         }
2025
2026         fn internal_revoke_and_ack(&self, their_node_id: &PublicKey, msg: &msgs::RevokeAndACK) -> Result<(), MsgHandleErrInternal> {
2027                 let (pending_forwards, mut pending_failures, short_channel_id) = {
2028                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2029                         let channel_state = channel_state_lock.borrow_parts();
2030                         match channel_state.by_id.entry(msg.channel_id) {
2031                                 hash_map::Entry::Occupied(mut chan) => {
2032                                         if chan.get().get_their_node_id() != *their_node_id {
2033                                                 //TODO: here and below MsgHandleErrInternal, #153 case
2034                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2035                                         }
2036                                         let (commitment_update, pending_forwards, pending_failures, closing_signed, chan_monitor) =
2037                                                 try_chan_entry!(self, chan.get_mut().revoke_and_ack(&msg, &*self.fee_estimator), channel_state, chan);
2038                                         if let Err(e) = self.monitor.add_update_monitor(chan_monitor.get_funding_txo().unwrap(), chan_monitor) {
2039                                                 return_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::CommitmentFirst, pending_forwards, pending_failures);
2040                                         }
2041                                         if let Some(updates) = commitment_update {
2042                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
2043                                                         node_id: their_node_id.clone(),
2044                                                         updates,
2045                                                 });
2046                                         }
2047                                         if let Some(msg) = closing_signed {
2048                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendClosingSigned {
2049                                                         node_id: their_node_id.clone(),
2050                                                         msg,
2051                                                 });
2052                                         }
2053                                         (pending_forwards, pending_failures, chan.get().get_short_channel_id().expect("RAA should only work on a short-id-available channel"))
2054                                 },
2055                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2056                         }
2057                 };
2058                 for failure in pending_failures.drain(..) {
2059                         self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), failure.0, &failure.1, failure.2);
2060                 }
2061                 self.forward_htlcs(&mut [(short_channel_id, pending_forwards)]);
2062
2063                 Ok(())
2064         }
2065
2066         fn internal_update_fee(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFee) -> Result<(), MsgHandleErrInternal> {
2067                 let mut channel_lock = self.channel_state.lock().unwrap();
2068                 let channel_state = channel_lock.borrow_parts();
2069                 match channel_state.by_id.entry(msg.channel_id) {
2070                         hash_map::Entry::Occupied(mut chan) => {
2071                                 if chan.get().get_their_node_id() != *their_node_id {
2072                                         //TODO: here and below MsgHandleErrInternal, #153 case
2073                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2074                                 }
2075                                 try_chan_entry!(self, chan.get_mut().update_fee(&*self.fee_estimator, &msg), channel_state, chan);
2076                         },
2077                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2078                 }
2079                 Ok(())
2080         }
2081
2082         fn internal_announcement_signatures(&self, their_node_id: &PublicKey, msg: &msgs::AnnouncementSignatures) -> Result<(), MsgHandleErrInternal> {
2083                 let mut channel_state_lock = self.channel_state.lock().unwrap();
2084                 let channel_state = channel_state_lock.borrow_parts();
2085
2086                 match channel_state.by_id.entry(msg.channel_id) {
2087                         hash_map::Entry::Occupied(mut chan) => {
2088                                 if chan.get().get_their_node_id() != *their_node_id {
2089                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2090                                 }
2091                                 if !chan.get().is_usable() {
2092                                         return Err(MsgHandleErrInternal::from_no_close(HandleError{err: "Got an announcement_signatures before we were ready for it", action: Some(msgs::ErrorAction::IgnoreError)}));
2093                                 }
2094
2095                                 let our_node_id = self.get_our_node_id();
2096                                 let (announcement, our_bitcoin_sig) =
2097                                         try_chan_entry!(self, chan.get_mut().get_channel_announcement(our_node_id.clone(), self.genesis_hash.clone()), channel_state, chan);
2098
2099                                 let were_node_one = announcement.node_id_1 == our_node_id;
2100                                 let msghash = Message::from_slice(&Sha256dHash::from_data(&announcement.encode()[..])[..]).unwrap();
2101                                 if self.secp_ctx.verify(&msghash, &msg.node_signature, if were_node_one { &announcement.node_id_2 } else { &announcement.node_id_1 }).is_err() ||
2102                                                 self.secp_ctx.verify(&msghash, &msg.bitcoin_signature, if were_node_one { &announcement.bitcoin_key_2 } else { &announcement.bitcoin_key_1 }).is_err() {
2103                                         try_chan_entry!(self, Err(ChannelError::Close("Bad announcement_signatures node_signature")), channel_state, chan);
2104                                 }
2105
2106                                 let our_node_sig = self.secp_ctx.sign(&msghash, &self.our_network_key);
2107
2108                                 channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelAnnouncement {
2109                                         msg: msgs::ChannelAnnouncement {
2110                                                 node_signature_1: if were_node_one { our_node_sig } else { msg.node_signature },
2111                                                 node_signature_2: if were_node_one { msg.node_signature } else { our_node_sig },
2112                                                 bitcoin_signature_1: if were_node_one { our_bitcoin_sig } else { msg.bitcoin_signature },
2113                                                 bitcoin_signature_2: if were_node_one { msg.bitcoin_signature } else { our_bitcoin_sig },
2114                                                 contents: announcement,
2115                                         },
2116                                         update_msg: self.get_channel_update(chan.get()).unwrap(), // can only fail if we're not in a ready state
2117                                 });
2118                         },
2119                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2120                 }
2121                 Ok(())
2122         }
2123
2124         fn internal_channel_reestablish(&self, their_node_id: &PublicKey, msg: &msgs::ChannelReestablish) -> Result<(), MsgHandleErrInternal> {
2125                 let mut channel_state_lock = self.channel_state.lock().unwrap();
2126                 let channel_state = channel_state_lock.borrow_parts();
2127
2128                 match channel_state.by_id.entry(msg.channel_id) {
2129                         hash_map::Entry::Occupied(mut chan) => {
2130                                 if chan.get().get_their_node_id() != *their_node_id {
2131                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2132                                 }
2133                                 let (funding_locked, revoke_and_ack, commitment_update, channel_monitor, mut order, shutdown) =
2134                                         try_chan_entry!(self, chan.get_mut().channel_reestablish(msg), channel_state, chan);
2135                                 if let Some(monitor) = channel_monitor {
2136                                         if let Err(e) = self.monitor.add_update_monitor(monitor.get_funding_txo().unwrap(), monitor) {
2137                                                 // channel_reestablish doesn't guarantee the order it returns is sensical
2138                                                 // for the messages it returns, but if we're setting what messages to
2139                                                 // re-transmit on monitor update success, we need to make sure it is sane.
2140                                                 if revoke_and_ack.is_none() {
2141                                                         order = RAACommitmentOrder::CommitmentFirst;
2142                                                 }
2143                                                 if commitment_update.is_none() {
2144                                                         order = RAACommitmentOrder::RevokeAndACKFirst;
2145                                                 }
2146                                                 return_monitor_err!(self, e, channel_state, chan, order);
2147                                                 //TODO: Resend the funding_locked if needed once we get the monitor running again
2148                                         }
2149                                 }
2150                                 if let Some(msg) = funding_locked {
2151                                         channel_state.pending_msg_events.push(events::MessageSendEvent::SendFundingLocked {
2152                                                 node_id: their_node_id.clone(),
2153                                                 msg
2154                                         });
2155                                 }
2156                                 macro_rules! send_raa { () => {
2157                                         if let Some(msg) = revoke_and_ack {
2158                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendRevokeAndACK {
2159                                                         node_id: their_node_id.clone(),
2160                                                         msg
2161                                                 });
2162                                         }
2163                                 } }
2164                                 macro_rules! send_cu { () => {
2165                                         if let Some(updates) = commitment_update {
2166                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
2167                                                         node_id: their_node_id.clone(),
2168                                                         updates
2169                                                 });
2170                                         }
2171                                 } }
2172                                 match order {
2173                                         RAACommitmentOrder::RevokeAndACKFirst => {
2174                                                 send_raa!();
2175                                                 send_cu!();
2176                                         },
2177                                         RAACommitmentOrder::CommitmentFirst => {
2178                                                 send_cu!();
2179                                                 send_raa!();
2180                                         },
2181                                 }
2182                                 if let Some(msg) = shutdown {
2183                                         channel_state.pending_msg_events.push(events::MessageSendEvent::SendShutdown {
2184                                                 node_id: their_node_id.clone(),
2185                                                 msg,
2186                                         });
2187                                 }
2188                                 Ok(())
2189                         },
2190                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2191                 }
2192         }
2193
2194         /// Begin Update fee process. Allowed only on an outbound channel.
2195         /// If successful, will generate a UpdateHTLCs event, so you should probably poll
2196         /// PeerManager::process_events afterwards.
2197         /// Note: This API is likely to change!
2198         #[doc(hidden)]
2199         pub fn update_fee(&self, channel_id: [u8;32], feerate_per_kw: u64) -> Result<(), APIError> {
2200                 let _ = self.total_consistency_lock.read().unwrap();
2201                 let their_node_id;
2202                 let err: Result<(), _> = loop {
2203                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2204                         let channel_state = channel_state_lock.borrow_parts();
2205
2206                         match channel_state.by_id.entry(channel_id) {
2207                                 hash_map::Entry::Vacant(_) => return Err(APIError::APIMisuseError{err: "Failed to find corresponding channel"}),
2208                                 hash_map::Entry::Occupied(mut chan) => {
2209                                         if !chan.get().is_outbound() {
2210                                                 return Err(APIError::APIMisuseError{err: "update_fee cannot be sent for an inbound channel"});
2211                                         }
2212                                         if chan.get().is_awaiting_monitor_update() {
2213                                                 return Err(APIError::MonitorUpdateFailed);
2214                                         }
2215                                         if !chan.get().is_live() {
2216                                                 return Err(APIError::ChannelUnavailable{err: "Channel is either not yet fully established or peer is currently disconnected"});
2217                                         }
2218                                         their_node_id = chan.get().get_their_node_id();
2219                                         if let Some((update_fee, commitment_signed, chan_monitor)) =
2220                                                         break_chan_entry!(self, chan.get_mut().send_update_fee_and_commit(feerate_per_kw), channel_state, chan)
2221                                         {
2222                                                 if let Err(_e) = self.monitor.add_update_monitor(chan_monitor.get_funding_txo().unwrap(), chan_monitor) {
2223                                                         unimplemented!();
2224                                                 }
2225                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
2226                                                         node_id: chan.get().get_their_node_id(),
2227                                                         updates: msgs::CommitmentUpdate {
2228                                                                 update_add_htlcs: Vec::new(),
2229                                                                 update_fulfill_htlcs: Vec::new(),
2230                                                                 update_fail_htlcs: Vec::new(),
2231                                                                 update_fail_malformed_htlcs: Vec::new(),
2232                                                                 update_fee: Some(update_fee),
2233                                                                 commitment_signed,
2234                                                         },
2235                                                 });
2236                                         }
2237                                 },
2238                         }
2239                         return Ok(())
2240                 };
2241
2242                 match handle_error!(self, err, their_node_id) {
2243                         Ok(_) => unreachable!(),
2244                         Err(e) => {
2245                                 if let Some(msgs::ErrorAction::IgnoreError) = e.action {
2246                                 } else {
2247                                         log_error!(self, "Got bad keys: {}!", e.err);
2248                                         let mut channel_state = self.channel_state.lock().unwrap();
2249                                         channel_state.pending_msg_events.push(events::MessageSendEvent::HandleError {
2250                                                 node_id: their_node_id,
2251                                                 action: e.action,
2252                                         });
2253                                 }
2254                                 Err(APIError::APIMisuseError { err: e.err })
2255                         },
2256                 }
2257         }
2258 }
2259
2260 impl events::MessageSendEventsProvider for ChannelManager {
2261         fn get_and_clear_pending_msg_events(&self) -> Vec<events::MessageSendEvent> {
2262                 // TODO: Event release to users and serialization is currently race-y: its very easy for a
2263                 // user to serialize a ChannelManager with pending events in it and lose those events on
2264                 // restart. This is doubly true for the fail/fulfill-backs from monitor events!
2265                 {
2266                         //TODO: This behavior should be documented.
2267                         for htlc_update in self.monitor.fetch_pending_htlc_updated() {
2268                                 if let Some(preimage) = htlc_update.payment_preimage {
2269                                         log_trace!(self, "Claiming HTLC with preimage {} from our monitor", log_bytes!(preimage.0));
2270                                         self.claim_funds_internal(self.channel_state.lock().unwrap(), htlc_update.source, preimage);
2271                                 } else {
2272                                         log_trace!(self, "Failing HTLC with hash {} from our monitor", log_bytes!(htlc_update.payment_hash.0));
2273                                         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() });
2274                                 }
2275                         }
2276                 }
2277
2278                 let mut ret = Vec::new();
2279                 let mut channel_state = self.channel_state.lock().unwrap();
2280                 mem::swap(&mut ret, &mut channel_state.pending_msg_events);
2281                 ret
2282         }
2283 }
2284
2285 impl events::EventsProvider for ChannelManager {
2286         fn get_and_clear_pending_events(&self) -> Vec<events::Event> {
2287                 // TODO: Event release to users and serialization is currently race-y: its very easy for a
2288                 // user to serialize a ChannelManager with pending events in it and lose those events on
2289                 // restart. This is doubly true for the fail/fulfill-backs from monitor events!
2290                 {
2291                         //TODO: This behavior should be documented.
2292                         for htlc_update in self.monitor.fetch_pending_htlc_updated() {
2293                                 if let Some(preimage) = htlc_update.payment_preimage {
2294                                         log_trace!(self, "Claiming HTLC with preimage {} from our monitor", log_bytes!(preimage.0));
2295                                         self.claim_funds_internal(self.channel_state.lock().unwrap(), htlc_update.source, preimage);
2296                                 } else {
2297                                         log_trace!(self, "Failing HTLC with hash {} from our monitor", log_bytes!(htlc_update.payment_hash.0));
2298                                         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() });
2299                                 }
2300                         }
2301                 }
2302
2303                 let mut ret = Vec::new();
2304                 let mut pending_events = self.pending_events.lock().unwrap();
2305                 mem::swap(&mut ret, &mut *pending_events);
2306                 ret
2307         }
2308 }
2309
2310 impl ChainListener for ChannelManager {
2311         fn block_connected(&self, header: &BlockHeader, height: u32, txn_matched: &[&Transaction], indexes_of_txn_matched: &[u32]) {
2312                 let header_hash = header.bitcoin_hash();
2313                 log_trace!(self, "Block {} at height {} connected with {} txn matched", header_hash, height, txn_matched.len());
2314                 let _ = self.total_consistency_lock.read().unwrap();
2315                 let mut failed_channels = Vec::new();
2316                 {
2317                         let mut channel_lock = self.channel_state.lock().unwrap();
2318                         let channel_state = channel_lock.borrow_parts();
2319                         let short_to_id = channel_state.short_to_id;
2320                         let pending_msg_events = channel_state.pending_msg_events;
2321                         channel_state.by_id.retain(|_, channel| {
2322                                 let chan_res = channel.block_connected(header, height, txn_matched, indexes_of_txn_matched);
2323                                 if let Ok(Some(funding_locked)) = chan_res {
2324                                         pending_msg_events.push(events::MessageSendEvent::SendFundingLocked {
2325                                                 node_id: channel.get_their_node_id(),
2326                                                 msg: funding_locked,
2327                                         });
2328                                         if let Some(announcement_sigs) = self.get_announcement_sigs(channel) {
2329                                                 pending_msg_events.push(events::MessageSendEvent::SendAnnouncementSignatures {
2330                                                         node_id: channel.get_their_node_id(),
2331                                                         msg: announcement_sigs,
2332                                                 });
2333                                         }
2334                                         short_to_id.insert(channel.get_short_channel_id().unwrap(), channel.channel_id());
2335                                 } else if let Err(e) = chan_res {
2336                                         pending_msg_events.push(events::MessageSendEvent::HandleError {
2337                                                 node_id: channel.get_their_node_id(),
2338                                                 action: Some(msgs::ErrorAction::SendErrorMessage { msg: e }),
2339                                         });
2340                                         return false;
2341                                 }
2342                                 if let Some(funding_txo) = channel.get_funding_txo() {
2343                                         for tx in txn_matched {
2344                                                 for inp in tx.input.iter() {
2345                                                         if inp.previous_output == funding_txo.into_bitcoin_outpoint() {
2346                                                                 log_trace!(self, "Detected channel-closing tx {} spending {}:{}, closing channel {}", tx.txid(), inp.previous_output.txid, inp.previous_output.vout, log_bytes!(channel.channel_id()));
2347                                                                 if let Some(short_id) = channel.get_short_channel_id() {
2348                                                                         short_to_id.remove(&short_id);
2349                                                                 }
2350                                                                 // It looks like our counterparty went on-chain. We go ahead and
2351                                                                 // broadcast our latest local state as well here, just in case its
2352                                                                 // some kind of SPV attack, though we expect these to be dropped.
2353                                                                 failed_channels.push(channel.force_shutdown());
2354                                                                 if let Ok(update) = self.get_channel_update(&channel) {
2355                                                                         pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
2356                                                                                 msg: update
2357                                                                         });
2358                                                                 }
2359                                                                 return false;
2360                                                         }
2361                                                 }
2362                                         }
2363                                 }
2364                                 if channel.is_funding_initiated() && channel.channel_monitor().would_broadcast_at_height(height) {
2365                                         if let Some(short_id) = channel.get_short_channel_id() {
2366                                                 short_to_id.remove(&short_id);
2367                                         }
2368                                         failed_channels.push(channel.force_shutdown());
2369                                         // If would_broadcast_at_height() is true, the channel_monitor will broadcast
2370                                         // the latest local tx for us, so we should skip that here (it doesn't really
2371                                         // hurt anything, but does make tests a bit simpler).
2372                                         failed_channels.last_mut().unwrap().0 = Vec::new();
2373                                         if let Ok(update) = self.get_channel_update(&channel) {
2374                                                 pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
2375                                                         msg: update
2376                                                 });
2377                                         }
2378                                         return false;
2379                                 }
2380                                 true
2381                         });
2382                 }
2383                 for failure in failed_channels.drain(..) {
2384                         self.finish_force_close_channel(failure);
2385                 }
2386                 self.latest_block_height.store(height as usize, Ordering::Release);
2387                 *self.last_block_hash.try_lock().expect("block_(dis)connected must not be called in parallel") = header_hash;
2388         }
2389
2390         /// We force-close the channel without letting our counterparty participate in the shutdown
2391         fn block_disconnected(&self, header: &BlockHeader) {
2392                 let _ = self.total_consistency_lock.read().unwrap();
2393                 let mut failed_channels = Vec::new();
2394                 {
2395                         let mut channel_lock = self.channel_state.lock().unwrap();
2396                         let channel_state = channel_lock.borrow_parts();
2397                         let short_to_id = channel_state.short_to_id;
2398                         let pending_msg_events = channel_state.pending_msg_events;
2399                         channel_state.by_id.retain(|_,  v| {
2400                                 if v.block_disconnected(header) {
2401                                         if let Some(short_id) = v.get_short_channel_id() {
2402                                                 short_to_id.remove(&short_id);
2403                                         }
2404                                         failed_channels.push(v.force_shutdown());
2405                                         if let Ok(update) = self.get_channel_update(&v) {
2406                                                 pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
2407                                                         msg: update
2408                                                 });
2409                                         }
2410                                         false
2411                                 } else {
2412                                         true
2413                                 }
2414                         });
2415                 }
2416                 for failure in failed_channels.drain(..) {
2417                         self.finish_force_close_channel(failure);
2418                 }
2419                 self.latest_block_height.fetch_sub(1, Ordering::AcqRel);
2420                 *self.last_block_hash.try_lock().expect("block_(dis)connected must not be called in parallel") = header.bitcoin_hash();
2421         }
2422 }
2423
2424 impl ChannelMessageHandler for ChannelManager {
2425         //TODO: Handle errors and close channel (or so)
2426         fn handle_open_channel(&self, their_node_id: &PublicKey, msg: &msgs::OpenChannel) -> Result<(), HandleError> {
2427                 let _ = self.total_consistency_lock.read().unwrap();
2428                 handle_error!(self, self.internal_open_channel(their_node_id, msg), their_node_id)
2429         }
2430
2431         fn handle_accept_channel(&self, their_node_id: &PublicKey, msg: &msgs::AcceptChannel) -> Result<(), HandleError> {
2432                 let _ = self.total_consistency_lock.read().unwrap();
2433                 handle_error!(self, self.internal_accept_channel(their_node_id, msg), their_node_id)
2434         }
2435
2436         fn handle_funding_created(&self, their_node_id: &PublicKey, msg: &msgs::FundingCreated) -> Result<(), HandleError> {
2437                 let _ = self.total_consistency_lock.read().unwrap();
2438                 handle_error!(self, self.internal_funding_created(their_node_id, msg), their_node_id)
2439         }
2440
2441         fn handle_funding_signed(&self, their_node_id: &PublicKey, msg: &msgs::FundingSigned) -> Result<(), HandleError> {
2442                 let _ = self.total_consistency_lock.read().unwrap();
2443                 handle_error!(self, self.internal_funding_signed(their_node_id, msg), their_node_id)
2444         }
2445
2446         fn handle_funding_locked(&self, their_node_id: &PublicKey, msg: &msgs::FundingLocked) -> Result<(), HandleError> {
2447                 let _ = self.total_consistency_lock.read().unwrap();
2448                 handle_error!(self, self.internal_funding_locked(their_node_id, msg), their_node_id)
2449         }
2450
2451         fn handle_shutdown(&self, their_node_id: &PublicKey, msg: &msgs::Shutdown) -> Result<(), HandleError> {
2452                 let _ = self.total_consistency_lock.read().unwrap();
2453                 handle_error!(self, self.internal_shutdown(their_node_id, msg), their_node_id)
2454         }
2455
2456         fn handle_closing_signed(&self, their_node_id: &PublicKey, msg: &msgs::ClosingSigned) -> Result<(), HandleError> {
2457                 let _ = self.total_consistency_lock.read().unwrap();
2458                 handle_error!(self, self.internal_closing_signed(their_node_id, msg), their_node_id)
2459         }
2460
2461         fn handle_update_add_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateAddHTLC) -> Result<(), msgs::HandleError> {
2462                 let _ = self.total_consistency_lock.read().unwrap();
2463                 handle_error!(self, self.internal_update_add_htlc(their_node_id, msg), their_node_id)
2464         }
2465
2466         fn handle_update_fulfill_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFulfillHTLC) -> Result<(), HandleError> {
2467                 let _ = self.total_consistency_lock.read().unwrap();
2468                 handle_error!(self, self.internal_update_fulfill_htlc(their_node_id, msg), their_node_id)
2469         }
2470
2471         fn handle_update_fail_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFailHTLC) -> Result<(), HandleError> {
2472                 let _ = self.total_consistency_lock.read().unwrap();
2473                 handle_error!(self, self.internal_update_fail_htlc(their_node_id, msg), their_node_id)
2474         }
2475
2476         fn handle_update_fail_malformed_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFailMalformedHTLC) -> Result<(), HandleError> {
2477                 let _ = self.total_consistency_lock.read().unwrap();
2478                 handle_error!(self, self.internal_update_fail_malformed_htlc(their_node_id, msg), their_node_id)
2479         }
2480
2481         fn handle_commitment_signed(&self, their_node_id: &PublicKey, msg: &msgs::CommitmentSigned) -> Result<(), HandleError> {
2482                 let _ = self.total_consistency_lock.read().unwrap();
2483                 handle_error!(self, self.internal_commitment_signed(their_node_id, msg), their_node_id)
2484         }
2485
2486         fn handle_revoke_and_ack(&self, their_node_id: &PublicKey, msg: &msgs::RevokeAndACK) -> Result<(), HandleError> {
2487                 let _ = self.total_consistency_lock.read().unwrap();
2488                 handle_error!(self, self.internal_revoke_and_ack(their_node_id, msg), their_node_id)
2489         }
2490
2491         fn handle_update_fee(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFee) -> Result<(), HandleError> {
2492                 let _ = self.total_consistency_lock.read().unwrap();
2493                 handle_error!(self, self.internal_update_fee(their_node_id, msg), their_node_id)
2494         }
2495
2496         fn handle_announcement_signatures(&self, their_node_id: &PublicKey, msg: &msgs::AnnouncementSignatures) -> Result<(), HandleError> {
2497                 let _ = self.total_consistency_lock.read().unwrap();
2498                 handle_error!(self, self.internal_announcement_signatures(their_node_id, msg), their_node_id)
2499         }
2500
2501         fn handle_channel_reestablish(&self, their_node_id: &PublicKey, msg: &msgs::ChannelReestablish) -> Result<(), HandleError> {
2502                 let _ = self.total_consistency_lock.read().unwrap();
2503                 handle_error!(self, self.internal_channel_reestablish(their_node_id, msg), their_node_id)
2504         }
2505
2506         fn peer_disconnected(&self, their_node_id: &PublicKey, no_connection_possible: bool) {
2507                 let _ = self.total_consistency_lock.read().unwrap();
2508                 let mut failed_channels = Vec::new();
2509                 let mut failed_payments = Vec::new();
2510                 {
2511                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2512                         let channel_state = channel_state_lock.borrow_parts();
2513                         let short_to_id = channel_state.short_to_id;
2514                         let pending_msg_events = channel_state.pending_msg_events;
2515                         if no_connection_possible {
2516                                 log_debug!(self, "Failing all channels with {} due to no_connection_possible", log_pubkey!(their_node_id));
2517                                 channel_state.by_id.retain(|_, chan| {
2518                                         if chan.get_their_node_id() == *their_node_id {
2519                                                 if let Some(short_id) = chan.get_short_channel_id() {
2520                                                         short_to_id.remove(&short_id);
2521                                                 }
2522                                                 failed_channels.push(chan.force_shutdown());
2523                                                 if let Ok(update) = self.get_channel_update(&chan) {
2524                                                         pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
2525                                                                 msg: update
2526                                                         });
2527                                                 }
2528                                                 false
2529                                         } else {
2530                                                 true
2531                                         }
2532                                 });
2533                         } else {
2534                                 log_debug!(self, "Marking channels with {} disconnected and generating channel_updates", log_pubkey!(their_node_id));
2535                                 channel_state.by_id.retain(|_, chan| {
2536                                         if chan.get_their_node_id() == *their_node_id {
2537                                                 //TODO: mark channel disabled (and maybe announce such after a timeout).
2538                                                 let failed_adds = chan.remove_uncommitted_htlcs_and_mark_paused();
2539                                                 if !failed_adds.is_empty() {
2540                                                         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
2541                                                         failed_payments.push((chan_update, failed_adds));
2542                                                 }
2543                                                 if chan.is_shutdown() {
2544                                                         if let Some(short_id) = chan.get_short_channel_id() {
2545                                                                 short_to_id.remove(&short_id);
2546                                                         }
2547                                                         return false;
2548                                                 }
2549                                         }
2550                                         true
2551                                 })
2552                         }
2553                 }
2554                 for failure in failed_channels.drain(..) {
2555                         self.finish_force_close_channel(failure);
2556                 }
2557                 for (chan_update, mut htlc_sources) in failed_payments {
2558                         for (htlc_source, payment_hash) in htlc_sources.drain(..) {
2559                                 self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), htlc_source, &payment_hash, HTLCFailReason::Reason { failure_code: 0x1000 | 7, data: chan_update.clone() });
2560                         }
2561                 }
2562         }
2563
2564         fn peer_connected(&self, their_node_id: &PublicKey) {
2565                 log_debug!(self, "Generating channel_reestablish events for {}", log_pubkey!(their_node_id));
2566
2567                 let _ = self.total_consistency_lock.read().unwrap();
2568                 let mut channel_state_lock = self.channel_state.lock().unwrap();
2569                 let channel_state = channel_state_lock.borrow_parts();
2570                 let pending_msg_events = channel_state.pending_msg_events;
2571                 channel_state.by_id.retain(|_, chan| {
2572                         if chan.get_their_node_id() == *their_node_id {
2573                                 if !chan.have_received_message() {
2574                                         // If we created this (outbound) channel while we were disconnected from the
2575                                         // peer we probably failed to send the open_channel message, which is now
2576                                         // lost. We can't have had anything pending related to this channel, so we just
2577                                         // drop it.
2578                                         false
2579                                 } else {
2580                                         pending_msg_events.push(events::MessageSendEvent::SendChannelReestablish {
2581                                                 node_id: chan.get_their_node_id(),
2582                                                 msg: chan.get_channel_reestablish(),
2583                                         });
2584                                         true
2585                                 }
2586                         } else { true }
2587                 });
2588                 //TODO: Also re-broadcast announcement_signatures
2589         }
2590
2591         fn handle_error(&self, their_node_id: &PublicKey, msg: &msgs::ErrorMessage) {
2592                 let _ = self.total_consistency_lock.read().unwrap();
2593
2594                 if msg.channel_id == [0; 32] {
2595                         for chan in self.list_channels() {
2596                                 if chan.remote_network_id == *their_node_id {
2597                                         self.force_close_channel(&chan.channel_id);
2598                                 }
2599                         }
2600                 } else {
2601                         self.force_close_channel(&msg.channel_id);
2602                 }
2603         }
2604 }
2605
2606 const SERIALIZATION_VERSION: u8 = 1;
2607 const MIN_SERIALIZATION_VERSION: u8 = 1;
2608
2609 impl Writeable for PendingForwardHTLCInfo {
2610         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
2611                 if let &Some(ref onion) = &self.onion_packet {
2612                         1u8.write(writer)?;
2613                         onion.write(writer)?;
2614                 } else {
2615                         0u8.write(writer)?;
2616                 }
2617                 self.incoming_shared_secret.write(writer)?;
2618                 self.payment_hash.write(writer)?;
2619                 self.short_channel_id.write(writer)?;
2620                 self.amt_to_forward.write(writer)?;
2621                 self.outgoing_cltv_value.write(writer)?;
2622                 Ok(())
2623         }
2624 }
2625
2626 impl<R: ::std::io::Read> Readable<R> for PendingForwardHTLCInfo {
2627         fn read(reader: &mut R) -> Result<PendingForwardHTLCInfo, DecodeError> {
2628                 let onion_packet = match <u8 as Readable<R>>::read(reader)? {
2629                         0 => None,
2630                         1 => Some(msgs::OnionPacket::read(reader)?),
2631                         _ => return Err(DecodeError::InvalidValue),
2632                 };
2633                 Ok(PendingForwardHTLCInfo {
2634                         onion_packet,
2635                         incoming_shared_secret: Readable::read(reader)?,
2636                         payment_hash: Readable::read(reader)?,
2637                         short_channel_id: Readable::read(reader)?,
2638                         amt_to_forward: Readable::read(reader)?,
2639                         outgoing_cltv_value: Readable::read(reader)?,
2640                 })
2641         }
2642 }
2643
2644 impl Writeable for HTLCFailureMsg {
2645         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
2646                 match self {
2647                         &HTLCFailureMsg::Relay(ref fail_msg) => {
2648                                 0u8.write(writer)?;
2649                                 fail_msg.write(writer)?;
2650                         },
2651                         &HTLCFailureMsg::Malformed(ref fail_msg) => {
2652                                 1u8.write(writer)?;
2653                                 fail_msg.write(writer)?;
2654                         }
2655                 }
2656                 Ok(())
2657         }
2658 }
2659
2660 impl<R: ::std::io::Read> Readable<R> for HTLCFailureMsg {
2661         fn read(reader: &mut R) -> Result<HTLCFailureMsg, DecodeError> {
2662                 match <u8 as Readable<R>>::read(reader)? {
2663                         0 => Ok(HTLCFailureMsg::Relay(Readable::read(reader)?)),
2664                         1 => Ok(HTLCFailureMsg::Malformed(Readable::read(reader)?)),
2665                         _ => Err(DecodeError::InvalidValue),
2666                 }
2667         }
2668 }
2669
2670 impl Writeable for PendingHTLCStatus {
2671         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
2672                 match self {
2673                         &PendingHTLCStatus::Forward(ref forward_info) => {
2674                                 0u8.write(writer)?;
2675                                 forward_info.write(writer)?;
2676                         },
2677                         &PendingHTLCStatus::Fail(ref fail_msg) => {
2678                                 1u8.write(writer)?;
2679                                 fail_msg.write(writer)?;
2680                         }
2681                 }
2682                 Ok(())
2683         }
2684 }
2685
2686 impl<R: ::std::io::Read> Readable<R> for PendingHTLCStatus {
2687         fn read(reader: &mut R) -> Result<PendingHTLCStatus, DecodeError> {
2688                 match <u8 as Readable<R>>::read(reader)? {
2689                         0 => Ok(PendingHTLCStatus::Forward(Readable::read(reader)?)),
2690                         1 => Ok(PendingHTLCStatus::Fail(Readable::read(reader)?)),
2691                         _ => Err(DecodeError::InvalidValue),
2692                 }
2693         }
2694 }
2695
2696 impl_writeable!(HTLCPreviousHopData, 0, {
2697         short_channel_id,
2698         htlc_id,
2699         incoming_packet_shared_secret
2700 });
2701
2702 impl Writeable for HTLCSource {
2703         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
2704                 match self {
2705                         &HTLCSource::PreviousHopData(ref hop_data) => {
2706                                 0u8.write(writer)?;
2707                                 hop_data.write(writer)?;
2708                         },
2709                         &HTLCSource::OutboundRoute { ref route, ref session_priv, ref first_hop_htlc_msat } => {
2710                                 1u8.write(writer)?;
2711                                 route.write(writer)?;
2712                                 session_priv.write(writer)?;
2713                                 first_hop_htlc_msat.write(writer)?;
2714                         }
2715                 }
2716                 Ok(())
2717         }
2718 }
2719
2720 impl<R: ::std::io::Read> Readable<R> for HTLCSource {
2721         fn read(reader: &mut R) -> Result<HTLCSource, DecodeError> {
2722                 match <u8 as Readable<R>>::read(reader)? {
2723                         0 => Ok(HTLCSource::PreviousHopData(Readable::read(reader)?)),
2724                         1 => Ok(HTLCSource::OutboundRoute {
2725                                 route: Readable::read(reader)?,
2726                                 session_priv: Readable::read(reader)?,
2727                                 first_hop_htlc_msat: Readable::read(reader)?,
2728                         }),
2729                         _ => Err(DecodeError::InvalidValue),
2730                 }
2731         }
2732 }
2733
2734 impl Writeable for HTLCFailReason {
2735         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
2736                 match self {
2737                         &HTLCFailReason::ErrorPacket { ref err } => {
2738                                 0u8.write(writer)?;
2739                                 err.write(writer)?;
2740                         },
2741                         &HTLCFailReason::Reason { ref failure_code, ref data } => {
2742                                 1u8.write(writer)?;
2743                                 failure_code.write(writer)?;
2744                                 data.write(writer)?;
2745                         }
2746                 }
2747                 Ok(())
2748         }
2749 }
2750
2751 impl<R: ::std::io::Read> Readable<R> for HTLCFailReason {
2752         fn read(reader: &mut R) -> Result<HTLCFailReason, DecodeError> {
2753                 match <u8 as Readable<R>>::read(reader)? {
2754                         0 => Ok(HTLCFailReason::ErrorPacket { err: Readable::read(reader)? }),
2755                         1 => Ok(HTLCFailReason::Reason {
2756                                 failure_code: Readable::read(reader)?,
2757                                 data: Readable::read(reader)?,
2758                         }),
2759                         _ => Err(DecodeError::InvalidValue),
2760                 }
2761         }
2762 }
2763
2764 impl Writeable for HTLCForwardInfo {
2765         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
2766                 match self {
2767                         &HTLCForwardInfo::AddHTLC { ref prev_short_channel_id, ref prev_htlc_id, ref forward_info } => {
2768                                 0u8.write(writer)?;
2769                                 prev_short_channel_id.write(writer)?;
2770                                 prev_htlc_id.write(writer)?;
2771                                 forward_info.write(writer)?;
2772                         },
2773                         &HTLCForwardInfo::FailHTLC { ref htlc_id, ref err_packet } => {
2774                                 1u8.write(writer)?;
2775                                 htlc_id.write(writer)?;
2776                                 err_packet.write(writer)?;
2777                         },
2778                 }
2779                 Ok(())
2780         }
2781 }
2782
2783 impl<R: ::std::io::Read> Readable<R> for HTLCForwardInfo {
2784         fn read(reader: &mut R) -> Result<HTLCForwardInfo, DecodeError> {
2785                 match <u8 as Readable<R>>::read(reader)? {
2786                         0 => Ok(HTLCForwardInfo::AddHTLC {
2787                                 prev_short_channel_id: Readable::read(reader)?,
2788                                 prev_htlc_id: Readable::read(reader)?,
2789                                 forward_info: Readable::read(reader)?,
2790                         }),
2791                         1 => Ok(HTLCForwardInfo::FailHTLC {
2792                                 htlc_id: Readable::read(reader)?,
2793                                 err_packet: Readable::read(reader)?,
2794                         }),
2795                         _ => Err(DecodeError::InvalidValue),
2796                 }
2797         }
2798 }
2799
2800 impl Writeable for ChannelManager {
2801         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
2802                 let _ = self.total_consistency_lock.write().unwrap();
2803
2804                 writer.write_all(&[SERIALIZATION_VERSION; 1])?;
2805                 writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
2806
2807                 self.genesis_hash.write(writer)?;
2808                 (self.latest_block_height.load(Ordering::Acquire) as u32).write(writer)?;
2809                 self.last_block_hash.lock().unwrap().write(writer)?;
2810
2811                 let channel_state = self.channel_state.lock().unwrap();
2812                 let mut unfunded_channels = 0;
2813                 for (_, channel) in channel_state.by_id.iter() {
2814                         if !channel.is_funding_initiated() {
2815                                 unfunded_channels += 1;
2816                         }
2817                 }
2818                 ((channel_state.by_id.len() - unfunded_channels) as u64).write(writer)?;
2819                 for (_, channel) in channel_state.by_id.iter() {
2820                         if channel.is_funding_initiated() {
2821                                 channel.write(writer)?;
2822                         }
2823                 }
2824
2825                 (channel_state.forward_htlcs.len() as u64).write(writer)?;
2826                 for (short_channel_id, pending_forwards) in channel_state.forward_htlcs.iter() {
2827                         short_channel_id.write(writer)?;
2828                         (pending_forwards.len() as u64).write(writer)?;
2829                         for forward in pending_forwards {
2830                                 forward.write(writer)?;
2831                         }
2832                 }
2833
2834                 (channel_state.claimable_htlcs.len() as u64).write(writer)?;
2835                 for (payment_hash, previous_hops) in channel_state.claimable_htlcs.iter() {
2836                         payment_hash.write(writer)?;
2837                         (previous_hops.len() as u64).write(writer)?;
2838                         for previous_hop in previous_hops {
2839                                 previous_hop.write(writer)?;
2840                         }
2841                 }
2842
2843                 Ok(())
2844         }
2845 }
2846
2847 /// Arguments for the creation of a ChannelManager that are not deserialized.
2848 ///
2849 /// At a high-level, the process for deserializing a ChannelManager and resuming normal operation
2850 /// is:
2851 /// 1) Deserialize all stored ChannelMonitors.
2852 /// 2) Deserialize the ChannelManager by filling in this struct and calling <(Sha256dHash,
2853 ///    ChannelManager)>::read(reader, args).
2854 ///    This may result in closing some Channels if the ChannelMonitor is newer than the stored
2855 ///    ChannelManager state to ensure no loss of funds. Thus, transactions may be broadcasted.
2856 /// 3) Register all relevant ChannelMonitor outpoints with your chain watch mechanism using
2857 ///    ChannelMonitor::get_monitored_outpoints and ChannelMonitor::get_funding_txo().
2858 /// 4) Reconnect blocks on your ChannelMonitors.
2859 /// 5) Move the ChannelMonitors into your local ManyChannelMonitor.
2860 /// 6) Disconnect/connect blocks on the ChannelManager.
2861 /// 7) Register the new ChannelManager with your ChainWatchInterface (this does not happen
2862 ///    automatically as it does in ChannelManager::new()).
2863 pub struct ChannelManagerReadArgs<'a> {
2864         /// The keys provider which will give us relevant keys. Some keys will be loaded during
2865         /// deserialization.
2866         pub keys_manager: Arc<KeysInterface>,
2867
2868         /// The fee_estimator for use in the ChannelManager in the future.
2869         ///
2870         /// No calls to the FeeEstimator will be made during deserialization.
2871         pub fee_estimator: Arc<FeeEstimator>,
2872         /// The ManyChannelMonitor for use in the ChannelManager in the future.
2873         ///
2874         /// No calls to the ManyChannelMonitor will be made during deserialization. It is assumed that
2875         /// you have deserialized ChannelMonitors separately and will add them to your
2876         /// ManyChannelMonitor after deserializing this ChannelManager.
2877         pub monitor: Arc<ManyChannelMonitor>,
2878         /// The ChainWatchInterface for use in the ChannelManager in the future.
2879         ///
2880         /// No calls to the ChainWatchInterface will be made during deserialization.
2881         pub chain_monitor: Arc<ChainWatchInterface>,
2882         /// The BroadcasterInterface which will be used in the ChannelManager in the future and may be
2883         /// used to broadcast the latest local commitment transactions of channels which must be
2884         /// force-closed during deserialization.
2885         pub tx_broadcaster: Arc<BroadcasterInterface>,
2886         /// The Logger for use in the ChannelManager and which may be used to log information during
2887         /// deserialization.
2888         pub logger: Arc<Logger>,
2889         /// Default settings used for new channels. Any existing channels will continue to use the
2890         /// runtime settings which were stored when the ChannelManager was serialized.
2891         pub default_config: UserConfig,
2892
2893         /// A map from channel funding outpoints to ChannelMonitors for those channels (ie
2894         /// value.get_funding_txo() should be the key).
2895         ///
2896         /// If a monitor is inconsistent with the channel state during deserialization the channel will
2897         /// be force-closed using the data in the channelmonitor and the Channel will be dropped. This
2898         /// is true for missing channels as well. If there is a monitor missing for which we find
2899         /// channel data Err(DecodeError::InvalidValue) will be returned.
2900         ///
2901         /// In such cases the latest local transactions will be sent to the tx_broadcaster included in
2902         /// this struct.
2903         pub channel_monitors: &'a HashMap<OutPoint, &'a ChannelMonitor>,
2904 }
2905
2906 impl<'a, R : ::std::io::Read> ReadableArgs<R, ChannelManagerReadArgs<'a>> for (Sha256dHash, ChannelManager) {
2907         fn read(reader: &mut R, args: ChannelManagerReadArgs<'a>) -> Result<Self, DecodeError> {
2908                 let _ver: u8 = Readable::read(reader)?;
2909                 let min_ver: u8 = Readable::read(reader)?;
2910                 if min_ver > SERIALIZATION_VERSION {
2911                         return Err(DecodeError::UnknownVersion);
2912                 }
2913
2914                 let genesis_hash: Sha256dHash = Readable::read(reader)?;
2915                 let latest_block_height: u32 = Readable::read(reader)?;
2916                 let last_block_hash: Sha256dHash = Readable::read(reader)?;
2917
2918                 let mut closed_channels = Vec::new();
2919
2920                 let channel_count: u64 = Readable::read(reader)?;
2921                 let mut funding_txo_set = HashSet::with_capacity(cmp::min(channel_count as usize, 128));
2922                 let mut by_id = HashMap::with_capacity(cmp::min(channel_count as usize, 128));
2923                 let mut short_to_id = HashMap::with_capacity(cmp::min(channel_count as usize, 128));
2924                 for _ in 0..channel_count {
2925                         let mut channel: Channel = ReadableArgs::read(reader, args.logger.clone())?;
2926                         if channel.last_block_connected != last_block_hash {
2927                                 return Err(DecodeError::InvalidValue);
2928                         }
2929
2930                         let funding_txo = channel.channel_monitor().get_funding_txo().ok_or(DecodeError::InvalidValue)?;
2931                         funding_txo_set.insert(funding_txo.clone());
2932                         if let Some(monitor) = args.channel_monitors.get(&funding_txo) {
2933                                 if channel.get_cur_local_commitment_transaction_number() != monitor.get_cur_local_commitment_number() ||
2934                                                 channel.get_revoked_remote_commitment_transaction_number() != monitor.get_min_seen_secret() ||
2935                                                 channel.get_cur_remote_commitment_transaction_number() != monitor.get_cur_remote_commitment_number() {
2936                                         let mut force_close_res = channel.force_shutdown();
2937                                         force_close_res.0 = monitor.get_latest_local_commitment_txn();
2938                                         closed_channels.push(force_close_res);
2939                                 } else {
2940                                         if let Some(short_channel_id) = channel.get_short_channel_id() {
2941                                                 short_to_id.insert(short_channel_id, channel.channel_id());
2942                                         }
2943                                         by_id.insert(channel.channel_id(), channel);
2944                                 }
2945                         } else {
2946                                 return Err(DecodeError::InvalidValue);
2947                         }
2948                 }
2949
2950                 for (ref funding_txo, ref monitor) in args.channel_monitors.iter() {
2951                         if !funding_txo_set.contains(funding_txo) {
2952                                 closed_channels.push((monitor.get_latest_local_commitment_txn(), Vec::new()));
2953                         }
2954                 }
2955
2956                 let forward_htlcs_count: u64 = Readable::read(reader)?;
2957                 let mut forward_htlcs = HashMap::with_capacity(cmp::min(forward_htlcs_count as usize, 128));
2958                 for _ in 0..forward_htlcs_count {
2959                         let short_channel_id = Readable::read(reader)?;
2960                         let pending_forwards_count: u64 = Readable::read(reader)?;
2961                         let mut pending_forwards = Vec::with_capacity(cmp::min(pending_forwards_count as usize, 128));
2962                         for _ in 0..pending_forwards_count {
2963                                 pending_forwards.push(Readable::read(reader)?);
2964                         }
2965                         forward_htlcs.insert(short_channel_id, pending_forwards);
2966                 }
2967
2968                 let claimable_htlcs_count: u64 = Readable::read(reader)?;
2969                 let mut claimable_htlcs = HashMap::with_capacity(cmp::min(claimable_htlcs_count as usize, 128));
2970                 for _ in 0..claimable_htlcs_count {
2971                         let payment_hash = Readable::read(reader)?;
2972                         let previous_hops_len: u64 = Readable::read(reader)?;
2973                         let mut previous_hops = Vec::with_capacity(cmp::min(previous_hops_len as usize, 2));
2974                         for _ in 0..previous_hops_len {
2975                                 previous_hops.push(Readable::read(reader)?);
2976                         }
2977                         claimable_htlcs.insert(payment_hash, previous_hops);
2978                 }
2979
2980                 let channel_manager = ChannelManager {
2981                         genesis_hash,
2982                         fee_estimator: args.fee_estimator,
2983                         monitor: args.monitor,
2984                         chain_monitor: args.chain_monitor,
2985                         tx_broadcaster: args.tx_broadcaster,
2986
2987                         latest_block_height: AtomicUsize::new(latest_block_height as usize),
2988                         last_block_hash: Mutex::new(last_block_hash),
2989                         secp_ctx: Secp256k1::new(),
2990
2991                         channel_state: Mutex::new(ChannelHolder {
2992                                 by_id,
2993                                 short_to_id,
2994                                 next_forward: Instant::now(),
2995                                 forward_htlcs,
2996                                 claimable_htlcs,
2997                                 pending_msg_events: Vec::new(),
2998                         }),
2999                         our_network_key: args.keys_manager.get_node_secret(),
3000
3001                         pending_events: Mutex::new(Vec::new()),
3002                         total_consistency_lock: RwLock::new(()),
3003                         keys_manager: args.keys_manager,
3004                         logger: args.logger,
3005                         default_configuration: args.default_config,
3006                 };
3007
3008                 for close_res in closed_channels.drain(..) {
3009                         channel_manager.finish_force_close_channel(close_res);
3010                         //TODO: Broadcast channel update for closed channels, but only after we've made a
3011                         //connection or two.
3012                 }
3013
3014                 Ok((last_block_hash.clone(), channel_manager))
3015         }
3016 }