913bbd62d3b946f061cb7b5148539e5382e004ce
[rust-lightning] / lightning / src / ln / channelmanager.rs
1 // This file is Copyright its original authors, visible in version control
2 // history.
3 //
4 // This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
5 // or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
6 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
7 // You may not use this file except in accordance with one or both of these
8 // licenses.
9
10 //! The top-level channel management and payment tracking stuff lives here.
11 //!
12 //! The ChannelManager is the main chunk of logic implementing the lightning protocol and is
13 //! responsible for tracking which channels are open, HTLCs are in flight and reestablishing those
14 //! upon reconnect to the relevant peer(s).
15 //!
16 //! It does not manage routing logic (see routing::router::get_route for that) nor does it manage constructing
17 //! on-chain transactions (it only monitors the chain to watch for any force-closes that might
18 //! imply it needs to fail HTLCs/payments/channels it manages).
19
20 use bitcoin::blockdata::block::BlockHeader;
21 use bitcoin::blockdata::constants::genesis_block;
22 use bitcoin::blockdata::transaction::Transaction;
23 use bitcoin::network::constants::Network;
24
25 use bitcoin::hashes::{Hash, HashEngine};
26 use bitcoin::hashes::hmac::{Hmac, HmacEngine};
27 use bitcoin::hashes::sha256::Hash as Sha256;
28 use bitcoin::hashes::sha256d::Hash as Sha256dHash;
29 use bitcoin::hashes::cmp::fixed_time_eq;
30 use bitcoin::hash_types::BlockHash;
31
32 use bitcoin::secp256k1::key::{SecretKey,PublicKey};
33 use bitcoin::secp256k1::Secp256k1;
34 use bitcoin::secp256k1::ecdh::SharedSecret;
35 use bitcoin::secp256k1;
36
37 use chain;
38 use chain::Watch;
39 use chain::chaininterface::{BroadcasterInterface,ChainListener,FeeEstimator};
40 use chain::transaction::OutPoint;
41 use ln::channel::{Channel, ChannelError};
42 use ln::channelmonitor::{ChannelMonitor, ChannelMonitorUpdate, ChannelMonitorUpdateErr, HTLC_FAIL_BACK_BUFFER, CLTV_CLAIM_BUFFER, LATENCY_GRACE_PERIOD_BLOCKS, ANTI_REORG_DELAY, MonitorEvent};
43 use ln::features::{InitFeatures, NodeFeatures};
44 use routing::router::{Route, RouteHop};
45 use ln::msgs;
46 use ln::msgs::NetAddress;
47 use ln::onion_utils;
48 use ln::msgs::{ChannelMessageHandler, DecodeError, LightningError, OptionalField};
49 use chain::keysinterface::{ChannelKeys, KeysInterface, KeysManager, InMemoryChannelKeys};
50 use util::config::UserConfig;
51 use util::events::{Event, EventsProvider, MessageSendEvent, MessageSendEventsProvider};
52 use util::{byte_utils, events};
53 use util::ser::{Readable, ReadableArgs, MaybeReadable, Writeable, Writer};
54 use util::chacha20::{ChaCha20, ChaChaReader};
55 use util::logger::Logger;
56 use util::errors::APIError;
57
58 use std::{cmp, mem};
59 use std::collections::{HashMap, hash_map, HashSet};
60 use std::io::{Cursor, Read};
61 use std::sync::{Arc, Mutex, MutexGuard, RwLock};
62 use std::sync::atomic::{AtomicUsize, Ordering};
63 use std::time::Duration;
64 use std::marker::{Sync, Send};
65 use std::ops::Deref;
66 use bitcoin::hashes::hex::ToHex;
67
68 // We hold various information about HTLC relay in the HTLC objects in Channel itself:
69 //
70 // Upon receipt of an HTLC from a peer, we'll give it a PendingHTLCStatus indicating if it should
71 // forward the HTLC with information it will give back to us when it does so, or if it should Fail
72 // the HTLC with the relevant message for the Channel to handle giving to the remote peer.
73 //
74 // Once said HTLC is committed in the Channel, if the PendingHTLCStatus indicated Forward, the
75 // Channel will return the PendingHTLCInfo back to us, and we will create an HTLCForwardInfo
76 // with it to track where it came from (in case of onwards-forward error), waiting a random delay
77 // before we forward it.
78 //
79 // We will then use HTLCForwardInfo's PendingHTLCInfo to construct an outbound HTLC, with a
80 // relevant HTLCSource::PreviousHopData filled in to indicate where it came from (which we can use
81 // to either fail-backwards or fulfill the HTLC backwards along the relevant path).
82 // Alternatively, we can fill an outbound HTLC with a HTLCSource::OutboundRoute indicating this is
83 // our payment, which we can use to decode errors or inform the user that the payment was sent.
84
85 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
86 enum PendingHTLCRouting {
87         Forward {
88                 onion_packet: msgs::OnionPacket,
89                 short_channel_id: u64, // This should be NonZero<u64> eventually when we bump MSRV
90         },
91         Receive {
92                 payment_data: Option<msgs::FinalOnionHopData>,
93                 incoming_cltv_expiry: u32, // Used to track when we should expire pending HTLCs that go unclaimed
94         },
95 }
96
97 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
98 pub(super) struct PendingHTLCInfo {
99         routing: PendingHTLCRouting,
100         incoming_shared_secret: [u8; 32],
101         payment_hash: PaymentHash,
102         pub(super) amt_to_forward: u64,
103         pub(super) outgoing_cltv_value: u32,
104 }
105
106 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
107 pub(super) enum HTLCFailureMsg {
108         Relay(msgs::UpdateFailHTLC),
109         Malformed(msgs::UpdateFailMalformedHTLC),
110 }
111
112 /// Stores whether we can't forward an HTLC or relevant forwarding info
113 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
114 pub(super) enum PendingHTLCStatus {
115         Forward(PendingHTLCInfo),
116         Fail(HTLCFailureMsg),
117 }
118
119 pub(super) enum HTLCForwardInfo {
120         AddHTLC {
121                 prev_short_channel_id: u64,
122                 prev_htlc_id: u64,
123                 forward_info: PendingHTLCInfo,
124         },
125         FailHTLC {
126                 htlc_id: u64,
127                 err_packet: msgs::OnionErrorPacket,
128         },
129 }
130
131 /// Tracks the inbound corresponding to an outbound HTLC
132 #[derive(Clone, PartialEq)]
133 pub(super) struct HTLCPreviousHopData {
134         short_channel_id: u64,
135         htlc_id: u64,
136         incoming_packet_shared_secret: [u8; 32],
137 }
138
139 struct ClaimableHTLC {
140         prev_hop: HTLCPreviousHopData,
141         value: u64,
142         /// Filled in when the HTLC was received with a payment_secret packet, which contains a
143         /// total_msat (which may differ from value if this is a Multi-Path Payment) and a
144         /// payment_secret which prevents path-probing attacks and can associate different HTLCs which
145         /// are part of the same payment.
146         payment_data: Option<msgs::FinalOnionHopData>,
147         cltv_expiry: u32,
148 }
149
150 /// Tracks the inbound corresponding to an outbound HTLC
151 #[derive(Clone, PartialEq)]
152 pub(super) enum HTLCSource {
153         PreviousHopData(HTLCPreviousHopData),
154         OutboundRoute {
155                 path: Vec<RouteHop>,
156                 session_priv: SecretKey,
157                 /// Technically we can recalculate this from the route, but we cache it here to avoid
158                 /// doing a double-pass on route when we get a failure back
159                 first_hop_htlc_msat: u64,
160         },
161 }
162 #[cfg(test)]
163 impl HTLCSource {
164         pub fn dummy() -> Self {
165                 HTLCSource::OutboundRoute {
166                         path: Vec::new(),
167                         session_priv: SecretKey::from_slice(&[1; 32]).unwrap(),
168                         first_hop_htlc_msat: 0,
169                 }
170         }
171 }
172
173 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
174 pub(super) enum HTLCFailReason {
175         LightningError {
176                 err: msgs::OnionErrorPacket,
177         },
178         Reason {
179                 failure_code: u16,
180                 data: Vec<u8>,
181         }
182 }
183
184 /// payment_hash type, use to cross-lock hop
185 /// (C-not exported) as we just use [u8; 32] directly
186 #[derive(Hash, Copy, Clone, PartialEq, Eq, Debug)]
187 pub struct PaymentHash(pub [u8;32]);
188 /// payment_preimage type, use to route payment between hop
189 /// (C-not exported) as we just use [u8; 32] directly
190 #[derive(Hash, Copy, Clone, PartialEq, Eq, Debug)]
191 pub struct PaymentPreimage(pub [u8;32]);
192 /// payment_secret type, use to authenticate sender to the receiver and tie MPP HTLCs together
193 /// (C-not exported) as we just use [u8; 32] directly
194 #[derive(Hash, Copy, Clone, PartialEq, Eq, Debug)]
195 pub struct PaymentSecret(pub [u8;32]);
196
197 type ShutdownResult = (Option<OutPoint>, ChannelMonitorUpdate, Vec<(HTLCSource, PaymentHash)>);
198
199 /// Error type returned across the channel_state mutex boundary. When an Err is generated for a
200 /// Channel, we generally end up with a ChannelError::Close for which we have to close the channel
201 /// immediately (ie with no further calls on it made). Thus, this step happens inside a
202 /// channel_state lock. We then return the set of things that need to be done outside the lock in
203 /// this struct and call handle_error!() on it.
204
205 struct MsgHandleErrInternal {
206         err: msgs::LightningError,
207         shutdown_finish: Option<(ShutdownResult, Option<msgs::ChannelUpdate>)>,
208 }
209 impl MsgHandleErrInternal {
210         #[inline]
211         fn send_err_msg_no_close(err: String, channel_id: [u8; 32]) -> Self {
212                 Self {
213                         err: LightningError {
214                                 err: err.clone(),
215                                 action: msgs::ErrorAction::SendErrorMessage {
216                                         msg: msgs::ErrorMessage {
217                                                 channel_id,
218                                                 data: err
219                                         },
220                                 },
221                         },
222                         shutdown_finish: None,
223                 }
224         }
225         #[inline]
226         fn ignore_no_close(err: String) -> Self {
227                 Self {
228                         err: LightningError {
229                                 err,
230                                 action: msgs::ErrorAction::IgnoreError,
231                         },
232                         shutdown_finish: None,
233                 }
234         }
235         #[inline]
236         fn from_no_close(err: msgs::LightningError) -> Self {
237                 Self { err, shutdown_finish: None }
238         }
239         #[inline]
240         fn from_finish_shutdown(err: String, channel_id: [u8; 32], shutdown_res: ShutdownResult, channel_update: Option<msgs::ChannelUpdate>) -> Self {
241                 Self {
242                         err: LightningError {
243                                 err: err.clone(),
244                                 action: msgs::ErrorAction::SendErrorMessage {
245                                         msg: msgs::ErrorMessage {
246                                                 channel_id,
247                                                 data: err
248                                         },
249                                 },
250                         },
251                         shutdown_finish: Some((shutdown_res, channel_update)),
252                 }
253         }
254         #[inline]
255         fn from_chan_no_close(err: ChannelError, channel_id: [u8; 32]) -> Self {
256                 Self {
257                         err: match err {
258                                 ChannelError::Ignore(msg) => LightningError {
259                                         err: msg,
260                                         action: msgs::ErrorAction::IgnoreError,
261                                 },
262                                 ChannelError::Close(msg) => LightningError {
263                                         err: msg.clone(),
264                                         action: msgs::ErrorAction::SendErrorMessage {
265                                                 msg: msgs::ErrorMessage {
266                                                         channel_id,
267                                                         data: msg
268                                                 },
269                                         },
270                                 },
271                                 ChannelError::CloseDelayBroadcast(msg) => LightningError {
272                                         err: msg.clone(),
273                                         action: msgs::ErrorAction::SendErrorMessage {
274                                                 msg: msgs::ErrorMessage {
275                                                         channel_id,
276                                                         data: msg
277                                                 },
278                                         },
279                                 },
280                         },
281                         shutdown_finish: None,
282                 }
283         }
284 }
285
286 /// We hold back HTLCs we intend to relay for a random interval greater than this (see
287 /// Event::PendingHTLCsForwardable for the API guidelines indicating how long should be waited).
288 /// This provides some limited amount of privacy. Ideally this would range from somewhere like one
289 /// second to 30 seconds, but people expect lightning to be, you know, kinda fast, sadly.
290 const MIN_HTLC_RELAY_HOLDING_CELL_MILLIS: u64 = 100;
291
292 /// For events which result in both a RevokeAndACK and a CommitmentUpdate, by default they should
293 /// be sent in the order they appear in the return value, however sometimes the order needs to be
294 /// variable at runtime (eg Channel::channel_reestablish needs to re-send messages in the order
295 /// they were originally sent). In those cases, this enum is also returned.
296 #[derive(Clone, PartialEq)]
297 pub(super) enum RAACommitmentOrder {
298         /// Send the CommitmentUpdate messages first
299         CommitmentFirst,
300         /// Send the RevokeAndACK message first
301         RevokeAndACKFirst,
302 }
303
304 // Note this is only exposed in cfg(test):
305 pub(super) struct ChannelHolder<ChanSigner: ChannelKeys> {
306         pub(super) by_id: HashMap<[u8; 32], Channel<ChanSigner>>,
307         pub(super) short_to_id: HashMap<u64, [u8; 32]>,
308         /// short channel id -> forward infos. Key of 0 means payments received
309         /// Note that while this is held in the same mutex as the channels themselves, no consistency
310         /// guarantees are made about the existence of a channel with the short id here, nor the short
311         /// ids in the PendingHTLCInfo!
312         pub(super) forward_htlcs: HashMap<u64, Vec<HTLCForwardInfo>>,
313         /// (payment_hash, payment_secret) -> Vec<HTLCs> for tracking HTLCs that
314         /// were to us and can be failed/claimed by the user
315         /// Note that while this is held in the same mutex as the channels themselves, no consistency
316         /// guarantees are made about the channels given here actually existing anymore by the time you
317         /// go to read them!
318         claimable_htlcs: HashMap<(PaymentHash, Option<PaymentSecret>), Vec<ClaimableHTLC>>,
319         /// Messages to send to peers - pushed to in the same lock that they are generated in (except
320         /// for broadcast messages, where ordering isn't as strict).
321         pub(super) pending_msg_events: Vec<MessageSendEvent>,
322 }
323
324 /// State we hold per-peer. In the future we should put channels in here, but for now we only hold
325 /// the latest Init features we heard from the peer.
326 struct PeerState {
327         latest_features: InitFeatures,
328 }
329
330 #[cfg(not(any(target_pointer_width = "32", target_pointer_width = "64")))]
331 const ERR: () = "You need at least 32 bit pointers (well, usize, but we'll assume they're the same) for ChannelManager::latest_block_height";
332
333 /// SimpleArcChannelManager is useful when you need a ChannelManager with a static lifetime, e.g.
334 /// when you're using lightning-net-tokio (since tokio::spawn requires parameters with static
335 /// lifetimes). Other times you can afford a reference, which is more efficient, in which case
336 /// SimpleRefChannelManager is the more appropriate type. Defining these type aliases prevents
337 /// issues such as overly long function definitions. Note that the ChannelManager can take any
338 /// type that implements KeysInterface for its keys manager, but this type alias chooses the
339 /// concrete type of the KeysManager.
340 pub type SimpleArcChannelManager<M, T, F, L> = Arc<ChannelManager<InMemoryChannelKeys, Arc<M>, Arc<T>, Arc<KeysManager>, Arc<F>, Arc<L>>>;
341
342 /// SimpleRefChannelManager is a type alias for a ChannelManager reference, and is the reference
343 /// counterpart to the SimpleArcChannelManager type alias. Use this type by default when you don't
344 /// need a ChannelManager with a static lifetime. You'll need a static lifetime in cases such as
345 /// usage of lightning-net-tokio (since tokio::spawn requires parameters with static lifetimes).
346 /// But if this is not necessary, using a reference is more efficient. Defining these type aliases
347 /// helps with issues such as long function definitions. Note that the ChannelManager can take any
348 /// type that implements KeysInterface for its keys manager, but this type alias chooses the
349 /// concrete type of the KeysManager.
350 pub type SimpleRefChannelManager<'a, 'b, 'c, 'd, 'e, M, T, F, L> = ChannelManager<InMemoryChannelKeys, &'a M, &'b T, &'c KeysManager, &'d F, &'e L>;
351
352 /// Manager which keeps track of a number of channels and sends messages to the appropriate
353 /// channel, also tracking HTLC preimages and forwarding onion packets appropriately.
354 ///
355 /// Implements ChannelMessageHandler, handling the multi-channel parts and passing things through
356 /// to individual Channels.
357 ///
358 /// Implements Writeable to write out all channel state to disk. Implies peer_disconnected() for
359 /// all peers during write/read (though does not modify this instance, only the instance being
360 /// serialized). This will result in any channels which have not yet exchanged funding_created (ie
361 /// called funding_transaction_generated for outbound channels).
362 ///
363 /// Note that you can be a bit lazier about writing out ChannelManager than you can be with
364 /// ChannelMonitors. With ChannelMonitors you MUST write each monitor update out to disk before
365 /// returning from chain::Watch::watch_/update_channel, with ChannelManagers, writing updates
366 /// happens out-of-band (and will prevent any other ChannelManager operations from occurring during
367 /// the serialization process). If the deserialized version is out-of-date compared to the
368 /// ChannelMonitors passed by reference to read(), those channels will be force-closed based on the
369 /// ChannelMonitor state and no funds will be lost (mod on-chain transaction fees).
370 ///
371 /// Note that the deserializer is only implemented for (Sha256dHash, ChannelManager), which
372 /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
373 /// the "reorg path" (ie call block_disconnected() until you get to a common block and then call
374 /// block_connected() to step towards your best block) upon deserialization before using the
375 /// object!
376 ///
377 /// Note that ChannelManager is responsible for tracking liveness of its channels and generating
378 /// ChannelUpdate messages informing peers that the channel is temporarily disabled. To avoid
379 /// spam due to quick disconnection/reconnection, updates are not sent until the channel has been
380 /// offline for a full minute. In order to track this, you must call
381 /// timer_chan_freshness_every_min roughly once per minute, though it doesn't have to be perfect.
382 ///
383 /// Rather than using a plain ChannelManager, it is preferable to use either a SimpleArcChannelManager
384 /// a SimpleRefChannelManager, for conciseness. See their documentation for more details, but
385 /// essentially you should default to using a SimpleRefChannelManager, and use a
386 /// SimpleArcChannelManager when you require a ChannelManager with a static lifetime, such as when
387 /// you're using lightning-net-tokio.
388 pub struct ChannelManager<ChanSigner: ChannelKeys, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
389         where M::Target: chain::Watch<Keys=ChanSigner>,
390         T::Target: BroadcasterInterface,
391         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
392         F::Target: FeeEstimator,
393                                 L::Target: Logger,
394 {
395         default_configuration: UserConfig,
396         genesis_hash: BlockHash,
397         fee_estimator: F,
398         chain_monitor: M,
399         tx_broadcaster: T,
400
401         #[cfg(test)]
402         pub(super) latest_block_height: AtomicUsize,
403         #[cfg(not(test))]
404         latest_block_height: AtomicUsize,
405         last_block_hash: Mutex<BlockHash>,
406         secp_ctx: Secp256k1<secp256k1::All>,
407
408         #[cfg(test)]
409         pub(super) channel_state: Mutex<ChannelHolder<ChanSigner>>,
410         #[cfg(not(test))]
411         channel_state: Mutex<ChannelHolder<ChanSigner>>,
412         our_network_key: SecretKey,
413
414         /// Used to track the last value sent in a node_announcement "timestamp" field. We ensure this
415         /// value increases strictly since we don't assume access to a time source.
416         last_node_announcement_serial: AtomicUsize,
417
418         /// The bulk of our storage will eventually be here (channels and message queues and the like).
419         /// If we are connected to a peer we always at least have an entry here, even if no channels
420         /// are currently open with that peer.
421         /// Because adding or removing an entry is rare, we usually take an outer read lock and then
422         /// operate on the inner value freely. Sadly, this prevents parallel operation when opening a
423         /// new channel.
424         per_peer_state: RwLock<HashMap<PublicKey, Mutex<PeerState>>>,
425
426         pending_events: Mutex<Vec<events::Event>>,
427         /// Used when we have to take a BIG lock to make sure everything is self-consistent.
428         /// Essentially just when we're serializing ourselves out.
429         /// Taken first everywhere where we are making changes before any other locks.
430         total_consistency_lock: RwLock<()>,
431
432         keys_manager: K,
433
434         logger: L,
435 }
436
437 /// The amount of time we require our counterparty wait to claim their money (ie time between when
438 /// we, or our watchtower, must check for them having broadcast a theft transaction).
439 pub(crate) const BREAKDOWN_TIMEOUT: u16 = 6 * 24;
440 /// The amount of time we're willing to wait to claim money back to us
441 pub(crate) const MAX_LOCAL_BREAKDOWN_TIMEOUT: u16 = 6 * 24 * 7;
442
443 /// The minimum number of blocks between an inbound HTLC's CLTV and the corresponding outbound
444 /// HTLC's CLTV. This should always be a few blocks greater than channelmonitor::CLTV_CLAIM_BUFFER,
445 /// ie the node we forwarded the payment on to should always have enough room to reliably time out
446 /// the HTLC via a full update_fail_htlc/commitment_signed dance before we hit the
447 /// CLTV_CLAIM_BUFFER point (we static assert that it's at least 3 blocks more).
448 const CLTV_EXPIRY_DELTA: u16 = 6 * 12; //TODO?
449 pub(super) const CLTV_FAR_FAR_AWAY: u32 = 6 * 24 * 7; //TODO?
450
451 // Check that our CLTV_EXPIRY is at least CLTV_CLAIM_BUFFER + ANTI_REORG_DELAY + LATENCY_GRACE_PERIOD_BLOCKS,
452 // ie that if the next-hop peer fails the HTLC within
453 // LATENCY_GRACE_PERIOD_BLOCKS then we'll still have CLTV_CLAIM_BUFFER left to timeout it onchain,
454 // then waiting ANTI_REORG_DELAY to be reorg-safe on the outbound HLTC and
455 // failing the corresponding htlc backward, and us now seeing the last block of ANTI_REORG_DELAY before
456 // LATENCY_GRACE_PERIOD_BLOCKS.
457 #[deny(const_err)]
458 #[allow(dead_code)]
459 const CHECK_CLTV_EXPIRY_SANITY: u32 = CLTV_EXPIRY_DELTA as u32 - LATENCY_GRACE_PERIOD_BLOCKS - CLTV_CLAIM_BUFFER - ANTI_REORG_DELAY - LATENCY_GRACE_PERIOD_BLOCKS;
460
461 // Check for ability of an attacker to make us fail on-chain by delaying inbound claim. See
462 // ChannelMontior::would_broadcast_at_height for a description of why this is needed.
463 #[deny(const_err)]
464 #[allow(dead_code)]
465 const CHECK_CLTV_EXPIRY_SANITY_2: u32 = CLTV_EXPIRY_DELTA as u32 - LATENCY_GRACE_PERIOD_BLOCKS - 2*CLTV_CLAIM_BUFFER;
466
467 /// Details of a channel, as returned by ChannelManager::list_channels and ChannelManager::list_usable_channels
468 pub struct ChannelDetails {
469         /// The channel's ID (prior to funding transaction generation, this is a random 32 bytes,
470         /// thereafter this is the txid of the funding transaction xor the funding transaction output).
471         /// Note that this means this value is *not* persistent - it can change once during the
472         /// lifetime of the channel.
473         pub channel_id: [u8; 32],
474         /// The position of the funding transaction in the chain. None if the funding transaction has
475         /// not yet been confirmed and the channel fully opened.
476         pub short_channel_id: Option<u64>,
477         /// The node_id of our counterparty
478         pub remote_network_id: PublicKey,
479         /// The Features the channel counterparty provided upon last connection.
480         /// Useful for routing as it is the most up-to-date copy of the counterparty's features and
481         /// many routing-relevant features are present in the init context.
482         pub counterparty_features: InitFeatures,
483         /// The value, in satoshis, of this channel as appears in the funding output
484         pub channel_value_satoshis: u64,
485         /// The user_id passed in to create_channel, or 0 if the channel was inbound.
486         pub user_id: u64,
487         /// The available outbound capacity for sending HTLCs to the remote peer. This does not include
488         /// any pending HTLCs which are not yet fully resolved (and, thus, who's balance is not
489         /// available for inclusion in new outbound HTLCs). This further does not include any pending
490         /// outgoing HTLCs which are awaiting some other resolution to be sent.
491         pub outbound_capacity_msat: u64,
492         /// The available inbound capacity for the remote peer to send HTLCs to us. This does not
493         /// include any pending HTLCs which are not yet fully resolved (and, thus, who's balance is not
494         /// available for inclusion in new inbound HTLCs).
495         /// Note that there are some corner cases not fully handled here, so the actual available
496         /// inbound capacity may be slightly higher than this.
497         pub inbound_capacity_msat: u64,
498         /// True if the channel is (a) confirmed and funding_locked messages have been exchanged, (b)
499         /// the peer is connected, and (c) no monitor update failure is pending resolution.
500         pub is_live: bool,
501 }
502
503 /// If a payment fails to send, it can be in one of several states. This enum is returned as the
504 /// Err() type describing which state the payment is in, see the description of individual enum
505 /// states for more.
506 #[derive(Debug)]
507 pub enum PaymentSendFailure {
508         /// A parameter which was passed to send_payment was invalid, preventing us from attempting to
509         /// send the payment at all. No channel state has been changed or messages sent to peers, and
510         /// once you've changed the parameter at error, you can freely retry the payment in full.
511         ParameterError(APIError),
512         /// A parameter in a single path which was passed to send_payment was invalid, preventing us
513         /// from attempting to send the payment at all. No channel state has been changed or messages
514         /// sent to peers, and once you've changed the parameter at error, you can freely retry the
515         /// payment in full.
516         ///
517         /// The results here are ordered the same as the paths in the route object which was passed to
518         /// send_payment.
519         PathParameterError(Vec<Result<(), APIError>>),
520         /// All paths which were attempted failed to send, with no channel state change taking place.
521         /// You can freely retry the payment in full (though you probably want to do so over different
522         /// paths than the ones selected).
523         AllFailedRetrySafe(Vec<APIError>),
524         /// Some paths which were attempted failed to send, though possibly not all. At least some
525         /// paths have irrevocably committed to the HTLC and retrying the payment in full would result
526         /// in over-/re-payment.
527         ///
528         /// The results here are ordered the same as the paths in the route object which was passed to
529         /// send_payment, and any Errs which are not APIError::MonitorUpdateFailed can be safely
530         /// retried (though there is currently no API with which to do so).
531         ///
532         /// Any entries which contain Err(APIError::MonitorUpdateFailed) or Ok(()) MUST NOT be retried
533         /// as they will result in over-/re-payment. These HTLCs all either successfully sent (in the
534         /// case of Ok(())) or will send once channel_monitor_updated is called on the next-hop channel
535         /// with the latest update_id.
536         PartialFailure(Vec<Result<(), APIError>>),
537 }
538
539 macro_rules! handle_error {
540         ($self: ident, $internal: expr, $counterparty_node_id: expr) => {
541                 match $internal {
542                         Ok(msg) => Ok(msg),
543                         Err(MsgHandleErrInternal { err, shutdown_finish }) => {
544                                 #[cfg(debug_assertions)]
545                                 {
546                                         // In testing, ensure there are no deadlocks where the lock is already held upon
547                                         // entering the macro.
548                                         assert!($self.channel_state.try_lock().is_ok());
549                                 }
550
551                                 let mut msg_events = Vec::with_capacity(2);
552
553                                 if let Some((shutdown_res, update_option)) = shutdown_finish {
554                                         $self.finish_force_close_channel(shutdown_res);
555                                         if let Some(update) = update_option {
556                                                 msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
557                                                         msg: update
558                                                 });
559                                         }
560                                 }
561
562                                 log_error!($self.logger, "{}", err.err);
563                                 if let msgs::ErrorAction::IgnoreError = err.action {
564                                 } else {
565                                         msg_events.push(events::MessageSendEvent::HandleError {
566                                                 node_id: $counterparty_node_id,
567                                                 action: err.action.clone()
568                                         });
569                                 }
570
571                                 if !msg_events.is_empty() {
572                                         $self.channel_state.lock().unwrap().pending_msg_events.append(&mut msg_events);
573                                 }
574
575                                 // Return error in case higher-API need one
576                                 Err(err)
577                         },
578                 }
579         }
580 }
581
582 macro_rules! break_chan_entry {
583         ($self: ident, $res: expr, $channel_state: expr, $entry: expr) => {
584                 match $res {
585                         Ok(res) => res,
586                         Err(ChannelError::Ignore(msg)) => {
587                                 break Err(MsgHandleErrInternal::from_chan_no_close(ChannelError::Ignore(msg), $entry.key().clone()))
588                         },
589                         Err(ChannelError::Close(msg)) => {
590                                 log_trace!($self.logger, "Closing channel {} due to Close-required error: {}", log_bytes!($entry.key()[..]), msg);
591                                 let (channel_id, mut chan) = $entry.remove_entry();
592                                 if let Some(short_id) = chan.get_short_channel_id() {
593                                         $channel_state.short_to_id.remove(&short_id);
594                                 }
595                                 break Err(MsgHandleErrInternal::from_finish_shutdown(msg, channel_id, chan.force_shutdown(true), $self.get_channel_update(&chan).ok()))
596                         },
597                         Err(ChannelError::CloseDelayBroadcast(_)) => { panic!("Wait is only generated on receipt of channel_reestablish, which is handled by try_chan_entry, we don't bother to support it here"); }
598                 }
599         }
600 }
601
602 macro_rules! try_chan_entry {
603         ($self: ident, $res: expr, $channel_state: expr, $entry: expr) => {
604                 match $res {
605                         Ok(res) => res,
606                         Err(ChannelError::Ignore(msg)) => {
607                                 return Err(MsgHandleErrInternal::from_chan_no_close(ChannelError::Ignore(msg), $entry.key().clone()))
608                         },
609                         Err(ChannelError::Close(msg)) => {
610                                 log_trace!($self.logger, "Closing channel {} due to Close-required error: {}", log_bytes!($entry.key()[..]), msg);
611                                 let (channel_id, mut chan) = $entry.remove_entry();
612                                 if let Some(short_id) = chan.get_short_channel_id() {
613                                         $channel_state.short_to_id.remove(&short_id);
614                                 }
615                                 return Err(MsgHandleErrInternal::from_finish_shutdown(msg, channel_id, chan.force_shutdown(true), $self.get_channel_update(&chan).ok()))
616                         },
617                         Err(ChannelError::CloseDelayBroadcast(msg)) => {
618                                 log_error!($self.logger, "Channel {} need to be shutdown but closing transactions not broadcast due to {}", log_bytes!($entry.key()[..]), msg);
619                                 let (channel_id, mut chan) = $entry.remove_entry();
620                                 if let Some(short_id) = chan.get_short_channel_id() {
621                                         $channel_state.short_to_id.remove(&short_id);
622                                 }
623                                 let shutdown_res = chan.force_shutdown(false);
624                                 return Err(MsgHandleErrInternal::from_finish_shutdown(msg, channel_id, shutdown_res, $self.get_channel_update(&chan).ok()))
625                         }
626                 }
627         }
628 }
629
630 macro_rules! handle_monitor_err {
631         ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $resend_raa: expr, $resend_commitment: expr) => {
632                 handle_monitor_err!($self, $err, $channel_state, $entry, $action_type, $resend_raa, $resend_commitment, Vec::new(), Vec::new())
633         };
634         ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $resend_raa: expr, $resend_commitment: expr, $failed_forwards: expr, $failed_fails: expr) => {
635                 match $err {
636                         ChannelMonitorUpdateErr::PermanentFailure => {
637                                 log_error!($self.logger, "Closing channel {} due to monitor update PermanentFailure", log_bytes!($entry.key()[..]));
638                                 let (channel_id, mut chan) = $entry.remove_entry();
639                                 if let Some(short_id) = chan.get_short_channel_id() {
640                                         $channel_state.short_to_id.remove(&short_id);
641                                 }
642                                 // TODO: $failed_fails is dropped here, which will cause other channels to hit the
643                                 // chain in a confused state! We need to move them into the ChannelMonitor which
644                                 // will be responsible for failing backwards once things confirm on-chain.
645                                 // It's ok that we drop $failed_forwards here - at this point we'd rather they
646                                 // broadcast HTLC-Timeout and pay the associated fees to get their funds back than
647                                 // us bother trying to claim it just to forward on to another peer. If we're
648                                 // splitting hairs we'd prefer to claim payments that were to us, but we haven't
649                                 // given up the preimage yet, so might as well just wait until the payment is
650                                 // retried, avoiding the on-chain fees.
651                                 let res: Result<(), _> = Err(MsgHandleErrInternal::from_finish_shutdown("ChannelMonitor storage failure".to_owned(), channel_id, chan.force_shutdown(true), $self.get_channel_update(&chan).ok()));
652                                 res
653                         },
654                         ChannelMonitorUpdateErr::TemporaryFailure => {
655                                 log_info!($self.logger, "Disabling channel {} due to monitor update TemporaryFailure. On restore will send {} and process {} forwards and {} fails",
656                                                 log_bytes!($entry.key()[..]),
657                                                 if $resend_commitment && $resend_raa {
658                                                                 match $action_type {
659                                                                         RAACommitmentOrder::CommitmentFirst => { "commitment then RAA" },
660                                                                         RAACommitmentOrder::RevokeAndACKFirst => { "RAA then commitment" },
661                                                                 }
662                                                         } else if $resend_commitment { "commitment" }
663                                                         else if $resend_raa { "RAA" }
664                                                         else { "nothing" },
665                                                 (&$failed_forwards as &Vec<(PendingHTLCInfo, u64)>).len(),
666                                                 (&$failed_fails as &Vec<(HTLCSource, PaymentHash, HTLCFailReason)>).len());
667                                 if !$resend_commitment {
668                                         debug_assert!($action_type == RAACommitmentOrder::RevokeAndACKFirst || !$resend_raa);
669                                 }
670                                 if !$resend_raa {
671                                         debug_assert!($action_type == RAACommitmentOrder::CommitmentFirst || !$resend_commitment);
672                                 }
673                                 $entry.get_mut().monitor_update_failed($resend_raa, $resend_commitment, $failed_forwards, $failed_fails);
674                                 Err(MsgHandleErrInternal::from_chan_no_close(ChannelError::Ignore("Failed to update ChannelMonitor".to_owned()), *$entry.key()))
675                         },
676                 }
677         }
678 }
679
680 macro_rules! return_monitor_err {
681         ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $resend_raa: expr, $resend_commitment: expr) => {
682                 return handle_monitor_err!($self, $err, $channel_state, $entry, $action_type, $resend_raa, $resend_commitment);
683         };
684         ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $resend_raa: expr, $resend_commitment: expr, $failed_forwards: expr, $failed_fails: expr) => {
685                 return handle_monitor_err!($self, $err, $channel_state, $entry, $action_type, $resend_raa, $resend_commitment, $failed_forwards, $failed_fails);
686         }
687 }
688
689 // Does not break in case of TemporaryFailure!
690 macro_rules! maybe_break_monitor_err {
691         ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $resend_raa: expr, $resend_commitment: expr) => {
692                 match (handle_monitor_err!($self, $err, $channel_state, $entry, $action_type, $resend_raa, $resend_commitment), $err) {
693                         (e, ChannelMonitorUpdateErr::PermanentFailure) => {
694                                 break e;
695                         },
696                         (_, ChannelMonitorUpdateErr::TemporaryFailure) => { },
697                 }
698         }
699 }
700
701 impl<ChanSigner: ChannelKeys, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelManager<ChanSigner, M, T, K, F, L>
702         where M::Target: chain::Watch<Keys=ChanSigner>,
703         T::Target: BroadcasterInterface,
704         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
705         F::Target: FeeEstimator,
706         L::Target: Logger,
707 {
708         /// Constructs a new ChannelManager to hold several channels and route between them.
709         ///
710         /// This is the main "logic hub" for all channel-related actions, and implements
711         /// ChannelMessageHandler.
712         ///
713         /// Non-proportional fees are fixed according to our risk using the provided fee estimator.
714         ///
715         /// panics if channel_value_satoshis is >= `MAX_FUNDING_SATOSHIS`!
716         ///
717         /// Users must provide the current blockchain height from which to track onchain channel
718         /// funding outpoints and send payments with reliable timelocks.
719         ///
720         /// Users need to notify the new ChannelManager when a new block is connected or
721         /// disconnected using its `block_connected` and `block_disconnected` methods.
722         /// However, rather than calling these methods directly, the user should register
723         /// the ChannelManager as a listener to the BlockNotifier and call the BlockNotifier's
724         /// `block_(dis)connected` methods, which will notify all registered listeners in one
725         /// go.
726         pub fn new(network: Network, fee_est: F, chain_monitor: M, tx_broadcaster: T, logger: L, keys_manager: K, config: UserConfig, current_blockchain_height: usize) -> Self {
727                 let secp_ctx = Secp256k1::new();
728
729                 ChannelManager {
730                         default_configuration: config.clone(),
731                         genesis_hash: genesis_block(network).header.block_hash(),
732                         fee_estimator: fee_est,
733                         chain_monitor,
734                         tx_broadcaster,
735
736                         latest_block_height: AtomicUsize::new(current_blockchain_height),
737                         last_block_hash: Mutex::new(Default::default()),
738                         secp_ctx,
739
740                         channel_state: Mutex::new(ChannelHolder{
741                                 by_id: HashMap::new(),
742                                 short_to_id: HashMap::new(),
743                                 forward_htlcs: HashMap::new(),
744                                 claimable_htlcs: HashMap::new(),
745                                 pending_msg_events: Vec::new(),
746                         }),
747                         our_network_key: keys_manager.get_node_secret(),
748
749                         last_node_announcement_serial: AtomicUsize::new(0),
750
751                         per_peer_state: RwLock::new(HashMap::new()),
752
753                         pending_events: Mutex::new(Vec::new()),
754                         total_consistency_lock: RwLock::new(()),
755
756                         keys_manager,
757
758                         logger,
759                 }
760         }
761
762         /// Creates a new outbound channel to the given remote node and with the given value.
763         ///
764         /// user_id will be provided back as user_channel_id in FundingGenerationReady and
765         /// FundingBroadcastSafe events to allow tracking of which events correspond with which
766         /// create_channel call. Note that user_channel_id defaults to 0 for inbound channels, so you
767         /// may wish to avoid using 0 for user_id here.
768         ///
769         /// If successful, will generate a SendOpenChannel message event, so you should probably poll
770         /// PeerManager::process_events afterwards.
771         ///
772         /// Raises APIError::APIMisuseError when channel_value_satoshis > 2**24 or push_msat is
773         /// greater than channel_value_satoshis * 1k or channel_value_satoshis is < 1000.
774         pub fn create_channel(&self, their_network_key: PublicKey, channel_value_satoshis: u64, push_msat: u64, user_id: u64, override_config: Option<UserConfig>) -> Result<(), APIError> {
775                 if channel_value_satoshis < 1000 {
776                         return Err(APIError::APIMisuseError { err: format!("Channel value must be at least 1000 satoshis. It was {}", channel_value_satoshis) });
777                 }
778
779                 let config = if override_config.is_some() { override_config.as_ref().unwrap() } else { &self.default_configuration };
780                 let channel = Channel::new_outbound(&self.fee_estimator, &self.keys_manager, their_network_key, channel_value_satoshis, push_msat, user_id, config)?;
781                 let res = channel.get_open_channel(self.genesis_hash.clone());
782
783                 let _ = self.total_consistency_lock.read().unwrap();
784                 let mut channel_state = self.channel_state.lock().unwrap();
785                 match channel_state.by_id.entry(channel.channel_id()) {
786                         hash_map::Entry::Occupied(_) => {
787                                 if cfg!(feature = "fuzztarget") {
788                                         return Err(APIError::APIMisuseError { err: "Fuzzy bad RNG".to_owned() });
789                                 } else {
790                                         panic!("RNG is bad???");
791                                 }
792                         },
793                         hash_map::Entry::Vacant(entry) => { entry.insert(channel); }
794                 }
795                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendOpenChannel {
796                         node_id: their_network_key,
797                         msg: res,
798                 });
799                 Ok(())
800         }
801
802         fn list_channels_with_filter<Fn: FnMut(&(&[u8; 32], &Channel<ChanSigner>)) -> bool>(&self, f: Fn) -> Vec<ChannelDetails> {
803                 let mut res = Vec::new();
804                 {
805                         let channel_state = self.channel_state.lock().unwrap();
806                         res.reserve(channel_state.by_id.len());
807                         for (channel_id, channel) in channel_state.by_id.iter().filter(f) {
808                                 let (inbound_capacity_msat, outbound_capacity_msat) = channel.get_inbound_outbound_available_balance_msat();
809                                 res.push(ChannelDetails {
810                                         channel_id: (*channel_id).clone(),
811                                         short_channel_id: channel.get_short_channel_id(),
812                                         remote_network_id: channel.get_counterparty_node_id(),
813                                         counterparty_features: InitFeatures::empty(),
814                                         channel_value_satoshis: channel.get_value_satoshis(),
815                                         inbound_capacity_msat,
816                                         outbound_capacity_msat,
817                                         user_id: channel.get_user_id(),
818                                         is_live: channel.is_live(),
819                                 });
820                         }
821                 }
822                 let per_peer_state = self.per_peer_state.read().unwrap();
823                 for chan in res.iter_mut() {
824                         if let Some(peer_state) = per_peer_state.get(&chan.remote_network_id) {
825                                 chan.counterparty_features = peer_state.lock().unwrap().latest_features.clone();
826                         }
827                 }
828                 res
829         }
830
831         /// Gets the list of open channels, in random order. See ChannelDetail field documentation for
832         /// more information.
833         pub fn list_channels(&self) -> Vec<ChannelDetails> {
834                 self.list_channels_with_filter(|_| true)
835         }
836
837         /// Gets the list of usable channels, in random order. Useful as an argument to
838         /// get_route to ensure non-announced channels are used.
839         ///
840         /// These are guaranteed to have their is_live value set to true, see the documentation for
841         /// ChannelDetails::is_live for more info on exactly what the criteria are.
842         pub fn list_usable_channels(&self) -> Vec<ChannelDetails> {
843                 // Note we use is_live here instead of usable which leads to somewhat confused
844                 // internal/external nomenclature, but that's ok cause that's probably what the user
845                 // really wanted anyway.
846                 self.list_channels_with_filter(|&(_, ref channel)| channel.is_live())
847         }
848
849         /// Begins the process of closing a channel. After this call (plus some timeout), no new HTLCs
850         /// will be accepted on the given channel, and after additional timeout/the closing of all
851         /// pending HTLCs, the channel will be closed on chain.
852         ///
853         /// May generate a SendShutdown message event on success, which should be relayed.
854         pub fn close_channel(&self, channel_id: &[u8; 32]) -> Result<(), APIError> {
855                 let _ = self.total_consistency_lock.read().unwrap();
856
857                 let (mut failed_htlcs, chan_option) = {
858                         let mut channel_state_lock = self.channel_state.lock().unwrap();
859                         let channel_state = &mut *channel_state_lock;
860                         match channel_state.by_id.entry(channel_id.clone()) {
861                                 hash_map::Entry::Occupied(mut chan_entry) => {
862                                         let (shutdown_msg, failed_htlcs) = chan_entry.get_mut().get_shutdown()?;
863                                         channel_state.pending_msg_events.push(events::MessageSendEvent::SendShutdown {
864                                                 node_id: chan_entry.get().get_counterparty_node_id(),
865                                                 msg: shutdown_msg
866                                         });
867                                         if chan_entry.get().is_shutdown() {
868                                                 if let Some(short_id) = chan_entry.get().get_short_channel_id() {
869                                                         channel_state.short_to_id.remove(&short_id);
870                                                 }
871                                                 (failed_htlcs, Some(chan_entry.remove_entry().1))
872                                         } else { (failed_htlcs, None) }
873                                 },
874                                 hash_map::Entry::Vacant(_) => return Err(APIError::ChannelUnavailable{err: "No such channel".to_owned()})
875                         }
876                 };
877                 for htlc_source in failed_htlcs.drain(..) {
878                         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() });
879                 }
880                 let chan_update = if let Some(chan) = chan_option {
881                         if let Ok(update) = self.get_channel_update(&chan) {
882                                 Some(update)
883                         } else { None }
884                 } else { None };
885
886                 if let Some(update) = chan_update {
887                         let mut channel_state = self.channel_state.lock().unwrap();
888                         channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
889                                 msg: update
890                         });
891                 }
892
893                 Ok(())
894         }
895
896         #[inline]
897         fn finish_force_close_channel(&self, shutdown_res: ShutdownResult) {
898                 let (funding_txo_option, monitor_update, mut failed_htlcs) = shutdown_res;
899                 log_trace!(self.logger, "Finishing force-closure of channel {} HTLCs to fail", failed_htlcs.len());
900                 for htlc_source in failed_htlcs.drain(..) {
901                         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() });
902                 }
903                 if let Some(funding_txo) = funding_txo_option {
904                         // There isn't anything we can do if we get an update failure - we're already
905                         // force-closing. The monitor update on the required in-memory copy should broadcast
906                         // the latest local state, which is the best we can do anyway. Thus, it is safe to
907                         // ignore the result here.
908                         let _ = self.chain_monitor.update_channel(funding_txo, monitor_update);
909                 }
910         }
911
912         /// Force closes a channel, immediately broadcasting the latest local commitment transaction to
913         /// the chain and rejecting new HTLCs on the given channel.
914         pub fn force_close_channel(&self, channel_id: &[u8; 32]) {
915                 let _ = self.total_consistency_lock.read().unwrap();
916
917                 let mut chan = {
918                         let mut channel_state_lock = self.channel_state.lock().unwrap();
919                         let channel_state = &mut *channel_state_lock;
920                         if let Some(chan) = channel_state.by_id.remove(channel_id) {
921                                 if let Some(short_id) = chan.get_short_channel_id() {
922                                         channel_state.short_to_id.remove(&short_id);
923                                 }
924                                 chan
925                         } else {
926                                 return;
927                         }
928                 };
929                 log_trace!(self.logger, "Force-closing channel {}", log_bytes!(channel_id[..]));
930                 self.finish_force_close_channel(chan.force_shutdown(true));
931                 if let Ok(update) = self.get_channel_update(&chan) {
932                         let mut channel_state = self.channel_state.lock().unwrap();
933                         channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
934                                 msg: update
935                         });
936                 }
937         }
938
939         /// Force close all channels, immediately broadcasting the latest local commitment transaction
940         /// for each to the chain and rejecting new HTLCs on each.
941         pub fn force_close_all_channels(&self) {
942                 for chan in self.list_channels() {
943                         self.force_close_channel(&chan.channel_id);
944                 }
945         }
946
947         fn decode_update_add_htlc_onion(&self, msg: &msgs::UpdateAddHTLC) -> (PendingHTLCStatus, MutexGuard<ChannelHolder<ChanSigner>>) {
948                 macro_rules! return_malformed_err {
949                         ($msg: expr, $err_code: expr) => {
950                                 {
951                                         log_info!(self.logger, "Failed to accept/forward incoming HTLC: {}", $msg);
952                                         return (PendingHTLCStatus::Fail(HTLCFailureMsg::Malformed(msgs::UpdateFailMalformedHTLC {
953                                                 channel_id: msg.channel_id,
954                                                 htlc_id: msg.htlc_id,
955                                                 sha256_of_onion: Sha256::hash(&msg.onion_routing_packet.hop_data).into_inner(),
956                                                 failure_code: $err_code,
957                                         })), self.channel_state.lock().unwrap());
958                                 }
959                         }
960                 }
961
962                 if let Err(_) = msg.onion_routing_packet.public_key {
963                         return_malformed_err!("invalid ephemeral pubkey", 0x8000 | 0x4000 | 6);
964                 }
965
966                 let shared_secret = {
967                         let mut arr = [0; 32];
968                         arr.copy_from_slice(&SharedSecret::new(&msg.onion_routing_packet.public_key.unwrap(), &self.our_network_key)[..]);
969                         arr
970                 };
971                 let (rho, mu) = onion_utils::gen_rho_mu_from_shared_secret(&shared_secret);
972
973                 if msg.onion_routing_packet.version != 0 {
974                         //TODO: Spec doesn't indicate if we should only hash hop_data here (and in other
975                         //sha256_of_onion error data packets), or the entire onion_routing_packet. Either way,
976                         //the hash doesn't really serve any purpose - in the case of hashing all data, the
977                         //receiving node would have to brute force to figure out which version was put in the
978                         //packet by the node that send us the message, in the case of hashing the hop_data, the
979                         //node knows the HMAC matched, so they already know what is there...
980                         return_malformed_err!("Unknown onion packet version", 0x8000 | 0x4000 | 4);
981                 }
982
983                 let mut hmac = HmacEngine::<Sha256>::new(&mu);
984                 hmac.input(&msg.onion_routing_packet.hop_data);
985                 hmac.input(&msg.payment_hash.0[..]);
986                 if !fixed_time_eq(&Hmac::from_engine(hmac).into_inner(), &msg.onion_routing_packet.hmac) {
987                         return_malformed_err!("HMAC Check failed", 0x8000 | 0x4000 | 5);
988                 }
989
990                 let mut channel_state = None;
991                 macro_rules! return_err {
992                         ($msg: expr, $err_code: expr, $data: expr) => {
993                                 {
994                                         log_info!(self.logger, "Failed to accept/forward incoming HTLC: {}", $msg);
995                                         if channel_state.is_none() {
996                                                 channel_state = Some(self.channel_state.lock().unwrap());
997                                         }
998                                         return (PendingHTLCStatus::Fail(HTLCFailureMsg::Relay(msgs::UpdateFailHTLC {
999                                                 channel_id: msg.channel_id,
1000                                                 htlc_id: msg.htlc_id,
1001                                                 reason: onion_utils::build_first_hop_failure_packet(&shared_secret, $err_code, $data),
1002                                         })), channel_state.unwrap());
1003                                 }
1004                         }
1005                 }
1006
1007                 let mut chacha = ChaCha20::new(&rho, &[0u8; 8]);
1008                 let mut chacha_stream = ChaChaReader { chacha: &mut chacha, read: Cursor::new(&msg.onion_routing_packet.hop_data[..]) };
1009                 let (next_hop_data, next_hop_hmac) = {
1010                         match msgs::OnionHopData::read(&mut chacha_stream) {
1011                                 Err(err) => {
1012                                         let error_code = match err {
1013                                                 msgs::DecodeError::UnknownVersion => 0x4000 | 1, // unknown realm byte
1014                                                 msgs::DecodeError::UnknownRequiredFeature|
1015                                                 msgs::DecodeError::InvalidValue|
1016                                                 msgs::DecodeError::ShortRead => 0x4000 | 22, // invalid_onion_payload
1017                                                 _ => 0x2000 | 2, // Should never happen
1018                                         };
1019                                         return_err!("Unable to decode our hop data", error_code, &[0;0]);
1020                                 },
1021                                 Ok(msg) => {
1022                                         let mut hmac = [0; 32];
1023                                         if let Err(_) = chacha_stream.read_exact(&mut hmac[..]) {
1024                                                 return_err!("Unable to decode hop data", 0x4000 | 22, &[0;0]);
1025                                         }
1026                                         (msg, hmac)
1027                                 },
1028                         }
1029                 };
1030
1031                 let pending_forward_info = if next_hop_hmac == [0; 32] {
1032                                 #[cfg(test)]
1033                                 {
1034                                         // In tests, make sure that the initial onion pcket data is, at least, non-0.
1035                                         // We could do some fancy randomness test here, but, ehh, whatever.
1036                                         // This checks for the issue where you can calculate the path length given the
1037                                         // onion data as all the path entries that the originator sent will be here
1038                                         // as-is (and were originally 0s).
1039                                         // Of course reverse path calculation is still pretty easy given naive routing
1040                                         // algorithms, but this fixes the most-obvious case.
1041                                         let mut next_bytes = [0; 32];
1042                                         chacha_stream.read_exact(&mut next_bytes).unwrap();
1043                                         assert_ne!(next_bytes[..], [0; 32][..]);
1044                                         chacha_stream.read_exact(&mut next_bytes).unwrap();
1045                                         assert_ne!(next_bytes[..], [0; 32][..]);
1046                                 }
1047
1048                                 // OUR PAYMENT!
1049                                 // final_expiry_too_soon
1050                                 // We have to have some headroom to broadcast on chain if we have the preimage, so make sure we have at least
1051                                 // HTLC_FAIL_BACK_BUFFER blocks to go.
1052                                 // Also, ensure that, in the case of an unknown payment hash, our payment logic has enough time to fail the HTLC backward
1053                                 // before our onchain logic triggers a channel closure (see HTLC_FAIL_BACK_BUFFER rational).
1054                                 if (msg.cltv_expiry as u64) <= self.latest_block_height.load(Ordering::Acquire) as u64 + HTLC_FAIL_BACK_BUFFER as u64 + 1 {
1055                                         return_err!("The final CLTV expiry is too soon to handle", 17, &[0;0]);
1056                                 }
1057                                 // final_incorrect_htlc_amount
1058                                 if next_hop_data.amt_to_forward > msg.amount_msat {
1059                                         return_err!("Upstream node sent less than we were supposed to receive in payment", 19, &byte_utils::be64_to_array(msg.amount_msat));
1060                                 }
1061                                 // final_incorrect_cltv_expiry
1062                                 if next_hop_data.outgoing_cltv_value != msg.cltv_expiry {
1063                                         return_err!("Upstream node set CLTV to the wrong value", 18, &byte_utils::be32_to_array(msg.cltv_expiry));
1064                                 }
1065
1066                                 let payment_data = match next_hop_data.format {
1067                                         msgs::OnionHopDataFormat::Legacy { .. } => None,
1068                                         msgs::OnionHopDataFormat::NonFinalNode { .. } => return_err!("Got non final data with an HMAC of 0", 0x4000 | 22, &[0;0]),
1069                                         msgs::OnionHopDataFormat::FinalNode { payment_data } => payment_data,
1070                                 };
1071
1072                                 // Note that we could obviously respond immediately with an update_fulfill_htlc
1073                                 // message, however that would leak that we are the recipient of this payment, so
1074                                 // instead we stay symmetric with the forwarding case, only responding (after a
1075                                 // delay) once they've send us a commitment_signed!
1076
1077                                 PendingHTLCStatus::Forward(PendingHTLCInfo {
1078                                         routing: PendingHTLCRouting::Receive {
1079                                                 payment_data,
1080                                                 incoming_cltv_expiry: msg.cltv_expiry,
1081                                         },
1082                                         payment_hash: msg.payment_hash.clone(),
1083                                         incoming_shared_secret: shared_secret,
1084                                         amt_to_forward: next_hop_data.amt_to_forward,
1085                                         outgoing_cltv_value: next_hop_data.outgoing_cltv_value,
1086                                 })
1087                         } else {
1088                                 let mut new_packet_data = [0; 20*65];
1089                                 let read_pos = chacha_stream.read(&mut new_packet_data).unwrap();
1090                                 #[cfg(debug_assertions)]
1091                                 {
1092                                         // Check two things:
1093                                         // a) that the behavior of our stream here will return Ok(0) even if the TLV
1094                                         //    read above emptied out our buffer and the unwrap() wont needlessly panic
1095                                         // b) that we didn't somehow magically end up with extra data.
1096                                         let mut t = [0; 1];
1097                                         debug_assert!(chacha_stream.read(&mut t).unwrap() == 0);
1098                                 }
1099                                 // Once we've emptied the set of bytes our peer gave us, encrypt 0 bytes until we
1100                                 // fill the onion hop data we'll forward to our next-hop peer.
1101                                 chacha_stream.chacha.process_in_place(&mut new_packet_data[read_pos..]);
1102
1103                                 let mut new_pubkey = msg.onion_routing_packet.public_key.unwrap();
1104
1105                                 let blinding_factor = {
1106                                         let mut sha = Sha256::engine();
1107                                         sha.input(&new_pubkey.serialize()[..]);
1108                                         sha.input(&shared_secret);
1109                                         Sha256::from_engine(sha).into_inner()
1110                                 };
1111
1112                                 let public_key = if let Err(e) = new_pubkey.mul_assign(&self.secp_ctx, &blinding_factor[..]) {
1113                                         Err(e)
1114                                 } else { Ok(new_pubkey) };
1115
1116                                 let outgoing_packet = msgs::OnionPacket {
1117                                         version: 0,
1118                                         public_key,
1119                                         hop_data: new_packet_data,
1120                                         hmac: next_hop_hmac.clone(),
1121                                 };
1122
1123                                 let short_channel_id = match next_hop_data.format {
1124                                         msgs::OnionHopDataFormat::Legacy { short_channel_id } => short_channel_id,
1125                                         msgs::OnionHopDataFormat::NonFinalNode { short_channel_id } => short_channel_id,
1126                                         msgs::OnionHopDataFormat::FinalNode { .. } => {
1127                                                 return_err!("Final Node OnionHopData provided for us as an intermediary node", 0x4000 | 22, &[0;0]);
1128                                         },
1129                                 };
1130
1131                                 PendingHTLCStatus::Forward(PendingHTLCInfo {
1132                                         routing: PendingHTLCRouting::Forward {
1133                                                 onion_packet: outgoing_packet,
1134                                                 short_channel_id: short_channel_id,
1135                                         },
1136                                         payment_hash: msg.payment_hash.clone(),
1137                                         incoming_shared_secret: shared_secret,
1138                                         amt_to_forward: next_hop_data.amt_to_forward,
1139                                         outgoing_cltv_value: next_hop_data.outgoing_cltv_value,
1140                                 })
1141                         };
1142
1143                 channel_state = Some(self.channel_state.lock().unwrap());
1144                 if let &PendingHTLCStatus::Forward(PendingHTLCInfo { ref routing, ref amt_to_forward, ref outgoing_cltv_value, .. }) = &pending_forward_info {
1145                         // If short_channel_id is 0 here, we'll reject the HTLC as there cannot be a channel
1146                         // with a short_channel_id of 0. This is important as various things later assume
1147                         // short_channel_id is non-0 in any ::Forward.
1148                         if let &PendingHTLCRouting::Forward { ref short_channel_id, .. } = routing {
1149                                 let id_option = channel_state.as_ref().unwrap().short_to_id.get(&short_channel_id).cloned();
1150                                 let forwarding_id = match id_option {
1151                                         None => { // unknown_next_peer
1152                                                 return_err!("Don't have available channel for forwarding as requested.", 0x4000 | 10, &[0;0]);
1153                                         },
1154                                         Some(id) => id.clone(),
1155                                 };
1156                                 if let Some((err, code, chan_update)) = loop {
1157                                         let chan = channel_state.as_mut().unwrap().by_id.get_mut(&forwarding_id).unwrap();
1158
1159                                         // Note that we could technically not return an error yet here and just hope
1160                                         // that the connection is reestablished or monitor updated by the time we get
1161                                         // around to doing the actual forward, but better to fail early if we can and
1162                                         // hopefully an attacker trying to path-trace payments cannot make this occur
1163                                         // on a small/per-node/per-channel scale.
1164                                         if !chan.is_live() { // channel_disabled
1165                                                 break Some(("Forwarding channel is not in a ready state.", 0x1000 | 20, Some(self.get_channel_update(chan).unwrap())));
1166                                         }
1167                                         if *amt_to_forward < chan.get_counterparty_htlc_minimum_msat() { // amount_below_minimum
1168                                                 break Some(("HTLC amount was below the htlc_minimum_msat", 0x1000 | 11, Some(self.get_channel_update(chan).unwrap())));
1169                                         }
1170                                         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_holder_fee_base_msat(&self.fee_estimator) as u64) });
1171                                         if fee.is_none() || msg.amount_msat < fee.unwrap() || (msg.amount_msat - fee.unwrap()) < *amt_to_forward { // fee_insufficient
1172                                                 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())));
1173                                         }
1174                                         if (msg.cltv_expiry as u64) < (*outgoing_cltv_value) as u64 + CLTV_EXPIRY_DELTA as u64 { // incorrect_cltv_expiry
1175                                                 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())));
1176                                         }
1177                                         let cur_height = self.latest_block_height.load(Ordering::Acquire) as u32 + 1;
1178                                         // Theoretically, channel counterparty shouldn't send us a HTLC expiring now, but we want to be robust wrt to counterparty
1179                                         // packet sanitization (see HTLC_FAIL_BACK_BUFFER rational)
1180                                         if msg.cltv_expiry <= cur_height + HTLC_FAIL_BACK_BUFFER as u32 { // expiry_too_soon
1181                                                 break Some(("CLTV expiry is too close", 0x1000 | 14, Some(self.get_channel_update(chan).unwrap())));
1182                                         }
1183                                         if msg.cltv_expiry > cur_height + CLTV_FAR_FAR_AWAY as u32 { // expiry_too_far
1184                                                 break Some(("CLTV expiry is too far in the future", 21, None));
1185                                         }
1186                                         // In theory, we would be safe against unitentional channel-closure, if we only required a margin of LATENCY_GRACE_PERIOD_BLOCKS.
1187                                         // But, to be safe against policy reception, we use a longuer delay.
1188                                         if (*outgoing_cltv_value) as u64 <= (cur_height + HTLC_FAIL_BACK_BUFFER) as u64 {
1189                                                 break Some(("Outgoing CLTV value is too soon", 0x1000 | 14, Some(self.get_channel_update(chan).unwrap())));
1190                                         }
1191
1192                                         break None;
1193                                 }
1194                                 {
1195                                         let mut res = Vec::with_capacity(8 + 128);
1196                                         if let Some(chan_update) = chan_update {
1197                                                 if code == 0x1000 | 11 || code == 0x1000 | 12 {
1198                                                         res.extend_from_slice(&byte_utils::be64_to_array(msg.amount_msat));
1199                                                 }
1200                                                 else if code == 0x1000 | 13 {
1201                                                         res.extend_from_slice(&byte_utils::be32_to_array(msg.cltv_expiry));
1202                                                 }
1203                                                 else if code == 0x1000 | 20 {
1204                                                         // TODO: underspecified, follow https://github.com/lightningnetwork/lightning-rfc/issues/791
1205                                                         res.extend_from_slice(&byte_utils::be16_to_array(0));
1206                                                 }
1207                                                 res.extend_from_slice(&chan_update.encode_with_len()[..]);
1208                                         }
1209                                         return_err!(err, code, &res[..]);
1210                                 }
1211                         }
1212                 }
1213
1214                 (pending_forward_info, channel_state.unwrap())
1215         }
1216
1217         /// only fails if the channel does not yet have an assigned short_id
1218         /// May be called with channel_state already locked!
1219         fn get_channel_update(&self, chan: &Channel<ChanSigner>) -> Result<msgs::ChannelUpdate, LightningError> {
1220                 let short_channel_id = match chan.get_short_channel_id() {
1221                         None => return Err(LightningError{err: "Channel not yet established".to_owned(), action: msgs::ErrorAction::IgnoreError}),
1222                         Some(id) => id,
1223                 };
1224
1225                 let were_node_one = PublicKey::from_secret_key(&self.secp_ctx, &self.our_network_key).serialize()[..] < chan.get_counterparty_node_id().serialize()[..];
1226
1227                 let unsigned = msgs::UnsignedChannelUpdate {
1228                         chain_hash: self.genesis_hash,
1229                         short_channel_id: short_channel_id,
1230                         timestamp: chan.get_update_time_counter(),
1231                         flags: (!were_node_one) as u8 | ((!chan.is_live() as u8) << 1),
1232                         cltv_expiry_delta: CLTV_EXPIRY_DELTA,
1233                         htlc_minimum_msat: chan.get_counterparty_htlc_minimum_msat(),
1234                         htlc_maximum_msat: OptionalField::Present(chan.get_announced_htlc_max_msat()),
1235                         fee_base_msat: chan.get_holder_fee_base_msat(&self.fee_estimator),
1236                         fee_proportional_millionths: chan.get_fee_proportional_millionths(),
1237                         excess_data: Vec::new(),
1238                 };
1239
1240                 let msg_hash = Sha256dHash::hash(&unsigned.encode()[..]);
1241                 let sig = self.secp_ctx.sign(&hash_to_message!(&msg_hash[..]), &self.our_network_key);
1242
1243                 Ok(msgs::ChannelUpdate {
1244                         signature: sig,
1245                         contents: unsigned
1246                 })
1247         }
1248
1249         // Only public for testing, this should otherwise never be called direcly
1250         pub(crate) fn send_payment_along_path(&self, path: &Vec<RouteHop>, payment_hash: &PaymentHash, payment_secret: &Option<PaymentSecret>, total_value: u64, cur_height: u32) -> Result<(), APIError> {
1251                 log_trace!(self.logger, "Attempting to send payment for path with next hop {}", path.first().unwrap().short_channel_id);
1252                 let prng_seed = self.keys_manager.get_secure_random_bytes();
1253                 let session_priv = SecretKey::from_slice(&self.keys_manager.get_secure_random_bytes()[..]).expect("RNG is busted");
1254
1255                 let onion_keys = onion_utils::construct_onion_keys(&self.secp_ctx, &path, &session_priv)
1256                         .map_err(|_| APIError::RouteError{err: "Pubkey along hop was maliciously selected"})?;
1257                 let (onion_payloads, htlc_msat, htlc_cltv) = onion_utils::build_onion_payloads(path, total_value, payment_secret, cur_height)?;
1258                 if onion_utils::route_size_insane(&onion_payloads) {
1259                         return Err(APIError::RouteError{err: "Route size too large considering onion data"});
1260                 }
1261                 let onion_packet = onion_utils::construct_onion_packet(onion_payloads, onion_keys, prng_seed, payment_hash);
1262
1263                 let _ = self.total_consistency_lock.read().unwrap();
1264
1265                 let err: Result<(), _> = loop {
1266                         let mut channel_lock = self.channel_state.lock().unwrap();
1267                         let id = match channel_lock.short_to_id.get(&path.first().unwrap().short_channel_id) {
1268                                 None => return Err(APIError::ChannelUnavailable{err: "No channel available with first hop!".to_owned()}),
1269                                 Some(id) => id.clone(),
1270                         };
1271
1272                         let channel_state = &mut *channel_lock;
1273                         if let hash_map::Entry::Occupied(mut chan) = channel_state.by_id.entry(id) {
1274                                 match {
1275                                         if chan.get().get_counterparty_node_id() != path.first().unwrap().pubkey {
1276                                                 return Err(APIError::RouteError{err: "Node ID mismatch on first hop!"});
1277                                         }
1278                                         if !chan.get().is_live() {
1279                                                 return Err(APIError::ChannelUnavailable{err: "Peer for first hop currently disconnected/pending monitor update!".to_owned()});
1280                                         }
1281                                         break_chan_entry!(self, chan.get_mut().send_htlc_and_commit(htlc_msat, payment_hash.clone(), htlc_cltv, HTLCSource::OutboundRoute {
1282                                                 path: path.clone(),
1283                                                 session_priv: session_priv.clone(),
1284                                                 first_hop_htlc_msat: htlc_msat,
1285                                         }, onion_packet, &self.logger), channel_state, chan)
1286                                 } {
1287                                         Some((update_add, commitment_signed, monitor_update)) => {
1288                                                 if let Err(e) = self.chain_monitor.update_channel(chan.get().get_funding_txo().unwrap(), monitor_update) {
1289                                                         maybe_break_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::CommitmentFirst, false, true);
1290                                                         // Note that MonitorUpdateFailed here indicates (per function docs)
1291                                                         // that we will resend the commitment update once monitor updating
1292                                                         // is restored. Therefore, we must return an error indicating that
1293                                                         // it is unsafe to retry the payment wholesale, which we do in the
1294                                                         // send_payment check for MonitorUpdateFailed, below.
1295                                                         return Err(APIError::MonitorUpdateFailed);
1296                                                 }
1297
1298                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
1299                                                         node_id: path.first().unwrap().pubkey,
1300                                                         updates: msgs::CommitmentUpdate {
1301                                                                 update_add_htlcs: vec![update_add],
1302                                                                 update_fulfill_htlcs: Vec::new(),
1303                                                                 update_fail_htlcs: Vec::new(),
1304                                                                 update_fail_malformed_htlcs: Vec::new(),
1305                                                                 update_fee: None,
1306                                                                 commitment_signed,
1307                                                         },
1308                                                 });
1309                                         },
1310                                         None => {},
1311                                 }
1312                         } else { unreachable!(); }
1313                         return Ok(());
1314                 };
1315
1316                 match handle_error!(self, err, path.first().unwrap().pubkey) {
1317                         Ok(_) => unreachable!(),
1318                         Err(e) => {
1319                                 Err(APIError::ChannelUnavailable { err: e.err })
1320                         },
1321                 }
1322         }
1323
1324         /// Sends a payment along a given route.
1325         ///
1326         /// Value parameters are provided via the last hop in route, see documentation for RouteHop
1327         /// fields for more info.
1328         ///
1329         /// Note that if the payment_hash already exists elsewhere (eg you're sending a duplicative
1330         /// payment), we don't do anything to stop you! We always try to ensure that if the provided
1331         /// next hop knows the preimage to payment_hash they can claim an additional amount as
1332         /// specified in the last hop in the route! Thus, you should probably do your own
1333         /// payment_preimage tracking (which you should already be doing as they represent "proof of
1334         /// payment") and prevent double-sends yourself.
1335         ///
1336         /// May generate SendHTLCs message(s) event on success, which should be relayed.
1337         ///
1338         /// Each path may have a different return value, and PaymentSendValue may return a Vec with
1339         /// each entry matching the corresponding-index entry in the route paths, see
1340         /// PaymentSendFailure for more info.
1341         ///
1342         /// In general, a path may raise:
1343         ///  * APIError::RouteError when an invalid route or forwarding parameter (cltv_delta, fee,
1344         ///    node public key) is specified.
1345         ///  * APIError::ChannelUnavailable if the next-hop channel is not available for updates
1346         ///    (including due to previous monitor update failure or new permanent monitor update
1347         ///    failure).
1348         ///  * APIError::MonitorUpdateFailed if a new monitor update failure prevented sending the
1349         ///    relevant updates.
1350         ///
1351         /// Note that depending on the type of the PaymentSendFailure the HTLC may have been
1352         /// irrevocably committed to on our end. In such a case, do NOT retry the payment with a
1353         /// different route unless you intend to pay twice!
1354         ///
1355         /// payment_secret is unrelated to payment_hash (or PaymentPreimage) and exists to authenticate
1356         /// the sender to the recipient and prevent payment-probing (deanonymization) attacks. For
1357         /// newer nodes, it will be provided to you in the invoice. If you do not have one, the Route
1358         /// must not contain multiple paths as multi-path payments require a recipient-provided
1359         /// payment_secret.
1360         /// If a payment_secret *is* provided, we assume that the invoice had the payment_secret feature
1361         /// bit set (either as required or as available). If multiple paths are present in the Route,
1362         /// we assume the invoice had the basic_mpp feature set.
1363         pub fn send_payment(&self, route: &Route, payment_hash: PaymentHash, payment_secret: &Option<PaymentSecret>) -> Result<(), PaymentSendFailure> {
1364                 if route.paths.len() < 1 {
1365                         return Err(PaymentSendFailure::ParameterError(APIError::RouteError{err: "There must be at least one path to send over"}));
1366                 }
1367                 if route.paths.len() > 10 {
1368                         // This limit is completely arbitrary - there aren't any real fundamental path-count
1369                         // limits. After we support retrying individual paths we should likely bump this, but
1370                         // for now more than 10 paths likely carries too much one-path failure.
1371                         return Err(PaymentSendFailure::ParameterError(APIError::RouteError{err: "Sending over more than 10 paths is not currently supported"}));
1372                 }
1373                 let mut total_value = 0;
1374                 let our_node_id = self.get_our_node_id();
1375                 let mut path_errs = Vec::with_capacity(route.paths.len());
1376                 'path_check: for path in route.paths.iter() {
1377                         if path.len() < 1 || path.len() > 20 {
1378                                 path_errs.push(Err(APIError::RouteError{err: "Path didn't go anywhere/had bogus size"}));
1379                                 continue 'path_check;
1380                         }
1381                         for (idx, hop) in path.iter().enumerate() {
1382                                 if idx != path.len() - 1 && hop.pubkey == our_node_id {
1383                                         path_errs.push(Err(APIError::RouteError{err: "Path went through us but wasn't a simple rebalance loop to us"}));
1384                                         continue 'path_check;
1385                                 }
1386                         }
1387                         total_value += path.last().unwrap().fee_msat;
1388                         path_errs.push(Ok(()));
1389                 }
1390                 if path_errs.iter().any(|e| e.is_err()) {
1391                         return Err(PaymentSendFailure::PathParameterError(path_errs));
1392                 }
1393
1394                 let cur_height = self.latest_block_height.load(Ordering::Acquire) as u32 + 1;
1395                 let mut results = Vec::new();
1396                 for path in route.paths.iter() {
1397                         results.push(self.send_payment_along_path(&path, &payment_hash, payment_secret, total_value, cur_height));
1398                 }
1399                 let mut has_ok = false;
1400                 let mut has_err = false;
1401                 for res in results.iter() {
1402                         if res.is_ok() { has_ok = true; }
1403                         if res.is_err() { has_err = true; }
1404                         if let &Err(APIError::MonitorUpdateFailed) = res {
1405                                 // MonitorUpdateFailed is inherently unsafe to retry, so we call it a
1406                                 // PartialFailure.
1407                                 has_err = true;
1408                                 has_ok = true;
1409                                 break;
1410                         }
1411                 }
1412                 if has_err && has_ok {
1413                         Err(PaymentSendFailure::PartialFailure(results))
1414                 } else if has_err {
1415                         Err(PaymentSendFailure::AllFailedRetrySafe(results.drain(..).map(|r| r.unwrap_err()).collect()))
1416                 } else {
1417                         Ok(())
1418                 }
1419         }
1420
1421         /// Call this upon creation of a funding transaction for the given channel.
1422         ///
1423         /// Note that ALL inputs in the transaction pointed to by funding_txo MUST spend SegWit outputs
1424         /// or your counterparty can steal your funds!
1425         ///
1426         /// Panics if a funding transaction has already been provided for this channel.
1427         ///
1428         /// May panic if the funding_txo is duplicative with some other channel (note that this should
1429         /// be trivially prevented by using unique funding transaction keys per-channel).
1430         pub fn funding_transaction_generated(&self, temporary_channel_id: &[u8; 32], funding_txo: OutPoint) {
1431                 let _ = self.total_consistency_lock.read().unwrap();
1432
1433                 let (chan, msg) = {
1434                         let (res, chan) = match self.channel_state.lock().unwrap().by_id.remove(temporary_channel_id) {
1435                                 Some(mut chan) => {
1436                                         (chan.get_outbound_funding_created(funding_txo, &self.logger)
1437                                                 .map_err(|e| if let ChannelError::Close(msg) = e {
1438                                                         MsgHandleErrInternal::from_finish_shutdown(msg, chan.channel_id(), chan.force_shutdown(true), None)
1439                                                 } else { unreachable!(); })
1440                                         , chan)
1441                                 },
1442                                 None => return
1443                         };
1444                         match handle_error!(self, res, chan.get_counterparty_node_id()) {
1445                                 Ok(funding_msg) => {
1446                                         (chan, funding_msg)
1447                                 },
1448                                 Err(_) => { return; }
1449                         }
1450                 };
1451
1452                 let mut channel_state = self.channel_state.lock().unwrap();
1453                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendFundingCreated {
1454                         node_id: chan.get_counterparty_node_id(),
1455                         msg: msg,
1456                 });
1457                 match channel_state.by_id.entry(chan.channel_id()) {
1458                         hash_map::Entry::Occupied(_) => {
1459                                 panic!("Generated duplicate funding txid?");
1460                         },
1461                         hash_map::Entry::Vacant(e) => {
1462                                 e.insert(chan);
1463                         }
1464                 }
1465         }
1466
1467         fn get_announcement_sigs(&self, chan: &Channel<ChanSigner>) -> Option<msgs::AnnouncementSignatures> {
1468                 if !chan.should_announce() {
1469                         log_trace!(self.logger, "Can't send announcement_signatures for private channel {}", log_bytes!(chan.channel_id()));
1470                         return None
1471                 }
1472
1473                 let (announcement, our_bitcoin_sig) = match chan.get_channel_announcement(self.get_our_node_id(), self.genesis_hash.clone()) {
1474                         Ok(res) => res,
1475                         Err(_) => return None, // Only in case of state precondition violations eg channel is closing
1476                 };
1477                 let msghash = hash_to_message!(&Sha256dHash::hash(&announcement.encode()[..])[..]);
1478                 let our_node_sig = self.secp_ctx.sign(&msghash, &self.our_network_key);
1479
1480                 Some(msgs::AnnouncementSignatures {
1481                         channel_id: chan.channel_id(),
1482                         short_channel_id: chan.get_short_channel_id().unwrap(),
1483                         node_signature: our_node_sig,
1484                         bitcoin_signature: our_bitcoin_sig,
1485                 })
1486         }
1487
1488         #[allow(dead_code)]
1489         // Messages of up to 64KB should never end up more than half full with addresses, as that would
1490         // be absurd. We ensure this by checking that at least 500 (our stated public contract on when
1491         // broadcast_node_announcement panics) of the maximum-length addresses would fit in a 64KB
1492         // message...
1493         const HALF_MESSAGE_IS_ADDRS: u32 = ::std::u16::MAX as u32 / (NetAddress::MAX_LEN as u32 + 1) / 2;
1494         #[deny(const_err)]
1495         #[allow(dead_code)]
1496         // ...by failing to compile if the number of addresses that would be half of a message is
1497         // smaller than 500:
1498         const STATIC_ASSERT: u32 = Self::HALF_MESSAGE_IS_ADDRS - 500;
1499
1500         /// Generates a signed node_announcement from the given arguments and creates a
1501         /// BroadcastNodeAnnouncement event. Note that such messages will be ignored unless peers have
1502         /// seen a channel_announcement from us (ie unless we have public channels open).
1503         ///
1504         /// RGB is a node "color" and alias is a printable human-readable string to describe this node
1505         /// to humans. They carry no in-protocol meaning.
1506         ///
1507         /// addresses represent the set (possibly empty) of socket addresses on which this node accepts
1508         /// incoming connections. These will be broadcast to the network, publicly tying these
1509         /// addresses together. If you wish to preserve user privacy, addresses should likely contain
1510         /// only Tor Onion addresses.
1511         ///
1512         /// Panics if addresses is absurdly large (more than 500).
1513         pub fn broadcast_node_announcement(&self, rgb: [u8; 3], alias: [u8; 32], addresses: Vec<NetAddress>) {
1514                 let _ = self.total_consistency_lock.read().unwrap();
1515
1516                 if addresses.len() > 500 {
1517                         panic!("More than half the message size was taken up by public addresses!");
1518                 }
1519
1520                 let announcement = msgs::UnsignedNodeAnnouncement {
1521                         features: NodeFeatures::known(),
1522                         timestamp: self.last_node_announcement_serial.fetch_add(1, Ordering::AcqRel) as u32,
1523                         node_id: self.get_our_node_id(),
1524                         rgb, alias, addresses,
1525                         excess_address_data: Vec::new(),
1526                         excess_data: Vec::new(),
1527                 };
1528                 let msghash = hash_to_message!(&Sha256dHash::hash(&announcement.encode()[..])[..]);
1529
1530                 let mut channel_state = self.channel_state.lock().unwrap();
1531                 channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastNodeAnnouncement {
1532                         msg: msgs::NodeAnnouncement {
1533                                 signature: self.secp_ctx.sign(&msghash, &self.our_network_key),
1534                                 contents: announcement
1535                         },
1536                 });
1537         }
1538
1539         /// Processes HTLCs which are pending waiting on random forward delay.
1540         ///
1541         /// Should only really ever be called in response to a PendingHTLCsForwardable event.
1542         /// Will likely generate further events.
1543         pub fn process_pending_htlc_forwards(&self) {
1544                 let _ = self.total_consistency_lock.read().unwrap();
1545
1546                 let mut new_events = Vec::new();
1547                 let mut failed_forwards = Vec::new();
1548                 let mut handle_errors = Vec::new();
1549                 {
1550                         let mut channel_state_lock = self.channel_state.lock().unwrap();
1551                         let channel_state = &mut *channel_state_lock;
1552
1553                         for (short_chan_id, mut pending_forwards) in channel_state.forward_htlcs.drain() {
1554                                 if short_chan_id != 0 {
1555                                         let forward_chan_id = match channel_state.short_to_id.get(&short_chan_id) {
1556                                                 Some(chan_id) => chan_id.clone(),
1557                                                 None => {
1558                                                         failed_forwards.reserve(pending_forwards.len());
1559                                                         for forward_info in pending_forwards.drain(..) {
1560                                                                 match forward_info {
1561                                                                         HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info } => {
1562                                                                                 let htlc_source = HTLCSource::PreviousHopData(HTLCPreviousHopData {
1563                                                                                         short_channel_id: prev_short_channel_id,
1564                                                                                         htlc_id: prev_htlc_id,
1565                                                                                         incoming_packet_shared_secret: forward_info.incoming_shared_secret,
1566                                                                                 });
1567                                                                                 failed_forwards.push((htlc_source, forward_info.payment_hash,
1568                                                                                         HTLCFailReason::Reason { failure_code: 0x4000 | 10, data: Vec::new() }
1569                                                                                 ));
1570                                                                         },
1571                                                                         HTLCForwardInfo::FailHTLC { .. } => {
1572                                                                                 // Channel went away before we could fail it. This implies
1573                                                                                 // the channel is now on chain and our counterparty is
1574                                                                                 // trying to broadcast the HTLC-Timeout, but that's their
1575                                                                                 // problem, not ours.
1576                                                                         }
1577                                                                 }
1578                                                         }
1579                                                         continue;
1580                                                 }
1581                                         };
1582                                         if let hash_map::Entry::Occupied(mut chan) = channel_state.by_id.entry(forward_chan_id) {
1583                                                 let mut add_htlc_msgs = Vec::new();
1584                                                 let mut fail_htlc_msgs = Vec::new();
1585                                                 for forward_info in pending_forwards.drain(..) {
1586                                                         match forward_info {
1587                                                                 HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info: PendingHTLCInfo {
1588                                                                                 routing: PendingHTLCRouting::Forward {
1589                                                                                         onion_packet, ..
1590                                                                                 }, incoming_shared_secret, payment_hash, amt_to_forward, outgoing_cltv_value }, } => {
1591                                                                         log_trace!(self.logger, "Adding HTLC from short id {} with payment_hash {} to channel with short id {} after delay", log_bytes!(payment_hash.0), prev_short_channel_id, short_chan_id);
1592                                                                         let htlc_source = HTLCSource::PreviousHopData(HTLCPreviousHopData {
1593                                                                                 short_channel_id: prev_short_channel_id,
1594                                                                                 htlc_id: prev_htlc_id,
1595                                                                                 incoming_packet_shared_secret: incoming_shared_secret,
1596                                                                         });
1597                                                                         match chan.get_mut().send_htlc(amt_to_forward, payment_hash, outgoing_cltv_value, htlc_source.clone(), onion_packet) {
1598                                                                                 Err(e) => {
1599                                                                                         if let ChannelError::Ignore(msg) = e {
1600                                                                                                 log_trace!(self.logger, "Failed to forward HTLC with payment_hash {}: {}", log_bytes!(payment_hash.0), msg);
1601                                                                                         } else {
1602                                                                                                 panic!("Stated return value requirements in send_htlc() were not met");
1603                                                                                         }
1604                                                                                         let chan_update = self.get_channel_update(chan.get()).unwrap();
1605                                                                                         failed_forwards.push((htlc_source, payment_hash,
1606                                                                                                 HTLCFailReason::Reason { failure_code: 0x1000 | 7, data: chan_update.encode_with_len() }
1607                                                                                         ));
1608                                                                                         continue;
1609                                                                                 },
1610                                                                                 Ok(update_add) => {
1611                                                                                         match update_add {
1612                                                                                                 Some(msg) => { add_htlc_msgs.push(msg); },
1613                                                                                                 None => {
1614                                                                                                         // Nothing to do here...we're waiting on a remote
1615                                                                                                         // revoke_and_ack before we can add anymore HTLCs. The Channel
1616                                                                                                         // will automatically handle building the update_add_htlc and
1617                                                                                                         // commitment_signed messages when we can.
1618                                                                                                         // TODO: Do some kind of timer to set the channel as !is_live()
1619                                                                                                         // as we don't really want others relying on us relaying through
1620                                                                                                         // this channel currently :/.
1621                                                                                                 }
1622                                                                                         }
1623                                                                                 }
1624                                                                         }
1625                                                                 },
1626                                                                 HTLCForwardInfo::AddHTLC { .. } => {
1627                                                                         panic!("short_channel_id != 0 should imply any pending_forward entries are of type Forward");
1628                                                                 },
1629                                                                 HTLCForwardInfo::FailHTLC { htlc_id, err_packet } => {
1630                                                                         log_trace!(self.logger, "Failing HTLC back to channel with short id {} after delay", short_chan_id);
1631                                                                         match chan.get_mut().get_update_fail_htlc(htlc_id, err_packet) {
1632                                                                                 Err(e) => {
1633                                                                                         if let ChannelError::Ignore(msg) = e {
1634                                                                                                 log_trace!(self.logger, "Failed to fail backwards to short_id {}: {}", short_chan_id, msg);
1635                                                                                         } else {
1636                                                                                                 panic!("Stated return value requirements in get_update_fail_htlc() were not met");
1637                                                                                         }
1638                                                                                         // fail-backs are best-effort, we probably already have one
1639                                                                                         // pending, and if not that's OK, if not, the channel is on
1640                                                                                         // the chain and sending the HTLC-Timeout is their problem.
1641                                                                                         continue;
1642                                                                                 },
1643                                                                                 Ok(Some(msg)) => { fail_htlc_msgs.push(msg); },
1644                                                                                 Ok(None) => {
1645                                                                                         // Nothing to do here...we're waiting on a remote
1646                                                                                         // revoke_and_ack before we can update the commitment
1647                                                                                         // transaction. The Channel will automatically handle
1648                                                                                         // building the update_fail_htlc and commitment_signed
1649                                                                                         // messages when we can.
1650                                                                                         // We don't need any kind of timer here as they should fail
1651                                                                                         // the channel onto the chain if they can't get our
1652                                                                                         // update_fail_htlc in time, it's not our problem.
1653                                                                                 }
1654                                                                         }
1655                                                                 },
1656                                                         }
1657                                                 }
1658
1659                                                 if !add_htlc_msgs.is_empty() || !fail_htlc_msgs.is_empty() {
1660                                                         let (commitment_msg, monitor_update) = match chan.get_mut().send_commitment(&self.logger) {
1661                                                                 Ok(res) => res,
1662                                                                 Err(e) => {
1663                                                                         // We surely failed send_commitment due to bad keys, in that case
1664                                                                         // close channel and then send error message to peer.
1665                                                                         let counterparty_node_id = chan.get().get_counterparty_node_id();
1666                                                                         let err: Result<(), _>  = match e {
1667                                                                                 ChannelError::Ignore(_) => {
1668                                                                                         panic!("Stated return value requirements in send_commitment() were not met");
1669                                                                                 },
1670                                                                                 ChannelError::Close(msg) => {
1671                                                                                         log_trace!(self.logger, "Closing channel {} due to Close-required error: {}", log_bytes!(chan.key()[..]), msg);
1672                                                                                         let (channel_id, mut channel) = chan.remove_entry();
1673                                                                                         if let Some(short_id) = channel.get_short_channel_id() {
1674                                                                                                 channel_state.short_to_id.remove(&short_id);
1675                                                                                         }
1676                                                                                         Err(MsgHandleErrInternal::from_finish_shutdown(msg, channel_id, channel.force_shutdown(true), self.get_channel_update(&channel).ok()))
1677                                                                                 },
1678                                                                                 ChannelError::CloseDelayBroadcast(_) => { panic!("Wait is only generated on receipt of channel_reestablish, which is handled by try_chan_entry, we don't bother to support it here"); }
1679                                                                         };
1680                                                                         handle_errors.push((counterparty_node_id, err));
1681                                                                         continue;
1682                                                                 }
1683                                                         };
1684                                                         if let Err(e) = self.chain_monitor.update_channel(chan.get().get_funding_txo().unwrap(), monitor_update) {
1685                                                                 handle_errors.push((chan.get().get_counterparty_node_id(), handle_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::CommitmentFirst, false, true)));
1686                                                                 continue;
1687                                                         }
1688                                                         channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
1689                                                                 node_id: chan.get().get_counterparty_node_id(),
1690                                                                 updates: msgs::CommitmentUpdate {
1691                                                                         update_add_htlcs: add_htlc_msgs,
1692                                                                         update_fulfill_htlcs: Vec::new(),
1693                                                                         update_fail_htlcs: fail_htlc_msgs,
1694                                                                         update_fail_malformed_htlcs: Vec::new(),
1695                                                                         update_fee: None,
1696                                                                         commitment_signed: commitment_msg,
1697                                                                 },
1698                                                         });
1699                                                 }
1700                                         } else {
1701                                                 unreachable!();
1702                                         }
1703                                 } else {
1704                                         for forward_info in pending_forwards.drain(..) {
1705                                                 match forward_info {
1706                                                         HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info: PendingHTLCInfo {
1707                                                                         routing: PendingHTLCRouting::Receive { payment_data, incoming_cltv_expiry },
1708                                                                         incoming_shared_secret, payment_hash, amt_to_forward, .. }, } => {
1709                                                                 let prev_hop = HTLCPreviousHopData {
1710                                                                         short_channel_id: prev_short_channel_id,
1711                                                                         htlc_id: prev_htlc_id,
1712                                                                         incoming_packet_shared_secret: incoming_shared_secret,
1713                                                                 };
1714
1715                                                                 let mut total_value = 0;
1716                                                                 let payment_secret_opt =
1717                                                                         if let &Some(ref data) = &payment_data { Some(data.payment_secret.clone()) } else { None };
1718                                                                 let htlcs = channel_state.claimable_htlcs.entry((payment_hash, payment_secret_opt))
1719                                                                         .or_insert(Vec::new());
1720                                                                 htlcs.push(ClaimableHTLC {
1721                                                                         prev_hop,
1722                                                                         value: amt_to_forward,
1723                                                                         payment_data: payment_data.clone(),
1724                                                                         cltv_expiry: incoming_cltv_expiry,
1725                                                                 });
1726                                                                 if let &Some(ref data) = &payment_data {
1727                                                                         for htlc in htlcs.iter() {
1728                                                                                 total_value += htlc.value;
1729                                                                                 if htlc.payment_data.as_ref().unwrap().total_msat != data.total_msat {
1730                                                                                         total_value = msgs::MAX_VALUE_MSAT;
1731                                                                                 }
1732                                                                                 if total_value >= msgs::MAX_VALUE_MSAT { break; }
1733                                                                         }
1734                                                                         if total_value >= msgs::MAX_VALUE_MSAT || total_value > data.total_msat  {
1735                                                                                 for htlc in htlcs.iter() {
1736                                                                                         let mut htlc_msat_height_data = byte_utils::be64_to_array(htlc.value).to_vec();
1737                                                                                         htlc_msat_height_data.extend_from_slice(
1738                                                                                                 &byte_utils::be32_to_array(
1739                                                                                                         self.latest_block_height.load(Ordering::Acquire)
1740                                                                                                                 as u32,
1741                                                                                                 ),
1742                                                                                         );
1743                                                                                         failed_forwards.push((HTLCSource::PreviousHopData(HTLCPreviousHopData {
1744                                                                                                         short_channel_id: htlc.prev_hop.short_channel_id,
1745                                                                                                         htlc_id: htlc.prev_hop.htlc_id,
1746                                                                                                         incoming_packet_shared_secret: htlc.prev_hop.incoming_packet_shared_secret,
1747                                                                                                 }), payment_hash,
1748                                                                                                 HTLCFailReason::Reason { failure_code: 0x4000 | 15, data: htlc_msat_height_data }
1749                                                                                         ));
1750                                                                                 }
1751                                                                         } else if total_value == data.total_msat {
1752                                                                                 new_events.push(events::Event::PaymentReceived {
1753                                                                                         payment_hash: payment_hash,
1754                                                                                         payment_secret: Some(data.payment_secret),
1755                                                                                         amt: total_value,
1756                                                                                 });
1757                                                                         }
1758                                                                 } else {
1759                                                                         new_events.push(events::Event::PaymentReceived {
1760                                                                                 payment_hash: payment_hash,
1761                                                                                 payment_secret: None,
1762                                                                                 amt: amt_to_forward,
1763                                                                         });
1764                                                                 }
1765                                                         },
1766                                                         HTLCForwardInfo::AddHTLC { .. } => {
1767                                                                 panic!("short_channel_id == 0 should imply any pending_forward entries are of type Receive");
1768                                                         },
1769                                                         HTLCForwardInfo::FailHTLC { .. } => {
1770                                                                 panic!("Got pending fail of our own HTLC");
1771                                                         }
1772                                                 }
1773                                         }
1774                                 }
1775                         }
1776                 }
1777
1778                 for (htlc_source, payment_hash, failure_reason) in failed_forwards.drain(..) {
1779                         self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), htlc_source, &payment_hash, failure_reason);
1780                 }
1781
1782                 for (counterparty_node_id, err) in handle_errors.drain(..) {
1783                         let _ = handle_error!(self, err, counterparty_node_id);
1784                 }
1785
1786                 if new_events.is_empty() { return }
1787                 let mut events = self.pending_events.lock().unwrap();
1788                 events.append(&mut new_events);
1789         }
1790
1791         /// If a peer is disconnected we mark any channels with that peer as 'disabled'.
1792         /// After some time, if channels are still disabled we need to broadcast a ChannelUpdate
1793         /// to inform the network about the uselessness of these channels.
1794         ///
1795         /// This method handles all the details, and must be called roughly once per minute.
1796         pub fn timer_chan_freshness_every_min(&self) {
1797                 let _ = self.total_consistency_lock.read().unwrap();
1798                 let mut channel_state_lock = self.channel_state.lock().unwrap();
1799                 let channel_state = &mut *channel_state_lock;
1800                 for (_, chan) in channel_state.by_id.iter_mut() {
1801                         if chan.is_disabled_staged() && !chan.is_live() {
1802                                 if let Ok(update) = self.get_channel_update(&chan) {
1803                                         channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
1804                                                 msg: update
1805                                         });
1806                                 }
1807                                 chan.to_fresh();
1808                         } else if chan.is_disabled_staged() && chan.is_live() {
1809                                 chan.to_fresh();
1810                         } else if chan.is_disabled_marked() {
1811                                 chan.to_disabled_staged();
1812                         }
1813                 }
1814         }
1815
1816         /// Indicates that the preimage for payment_hash is unknown or the received amount is incorrect
1817         /// after a PaymentReceived event, failing the HTLC back to its origin and freeing resources
1818         /// along the path (including in our own channel on which we received it).
1819         /// Returns false if no payment was found to fail backwards, true if the process of failing the
1820         /// HTLC backwards has been started.
1821         pub fn fail_htlc_backwards(&self, payment_hash: &PaymentHash, payment_secret: &Option<PaymentSecret>) -> bool {
1822                 let _ = self.total_consistency_lock.read().unwrap();
1823
1824                 let mut channel_state = Some(self.channel_state.lock().unwrap());
1825                 let removed_source = channel_state.as_mut().unwrap().claimable_htlcs.remove(&(*payment_hash, *payment_secret));
1826                 if let Some(mut sources) = removed_source {
1827                         for htlc in sources.drain(..) {
1828                                 if channel_state.is_none() { channel_state = Some(self.channel_state.lock().unwrap()); }
1829                                 let mut htlc_msat_height_data = byte_utils::be64_to_array(htlc.value).to_vec();
1830                                 htlc_msat_height_data.extend_from_slice(&byte_utils::be32_to_array(
1831                                         self.latest_block_height.load(Ordering::Acquire) as u32,
1832                                 ));
1833                                 self.fail_htlc_backwards_internal(channel_state.take().unwrap(),
1834                                                 HTLCSource::PreviousHopData(htlc.prev_hop), payment_hash,
1835                                                 HTLCFailReason::Reason { failure_code: 0x4000 | 15, data: htlc_msat_height_data });
1836                         }
1837                         true
1838                 } else { false }
1839         }
1840
1841         // Fail a list of HTLCs that were just freed from the holding cell. The HTLCs need to be
1842         // failed backwards or, if they were one of our outgoing HTLCs, then their failure needs to
1843         // be surfaced to the user.
1844         fn fail_holding_cell_htlcs(&self, mut htlcs_to_fail: Vec<(HTLCSource, PaymentHash)>, channel_id: [u8; 32]) {
1845                 for (htlc_src, payment_hash) in htlcs_to_fail.drain(..) {
1846                         match htlc_src {
1847                                 HTLCSource::PreviousHopData(HTLCPreviousHopData { .. }) => {
1848                                         let (failure_code, onion_failure_data) =
1849                                                 match self.channel_state.lock().unwrap().by_id.entry(channel_id) {
1850                                                         hash_map::Entry::Occupied(chan_entry) => {
1851                                                                 if let Ok(upd) = self.get_channel_update(&chan_entry.get()) {
1852                                                                         (0x1000|7, upd.encode_with_len())
1853                                                                 } else {
1854                                                                         (0x4000|10, Vec::new())
1855                                                                 }
1856                                                         },
1857                                                         hash_map::Entry::Vacant(_) => (0x4000|10, Vec::new())
1858                                                 };
1859                                         let channel_state = self.channel_state.lock().unwrap();
1860                                         self.fail_htlc_backwards_internal(channel_state,
1861                                                 htlc_src, &payment_hash, HTLCFailReason::Reason { failure_code, data: onion_failure_data});
1862                                 },
1863                                 HTLCSource::OutboundRoute { .. } => {
1864                                         self.pending_events.lock().unwrap().push(
1865                                                 events::Event::PaymentFailed {
1866                                                         payment_hash,
1867                                                         rejected_by_dest: false,
1868 #[cfg(test)]
1869                                                         error_code: None,
1870 #[cfg(test)]
1871                                                         error_data: None,
1872                                                 }
1873                                         )
1874                                 },
1875                         };
1876                 }
1877         }
1878
1879         /// Fails an HTLC backwards to the sender of it to us.
1880         /// Note that while we take a channel_state lock as input, we do *not* assume consistency here.
1881         /// There are several callsites that do stupid things like loop over a list of payment_hashes
1882         /// to fail and take the channel_state lock for each iteration (as we take ownership and may
1883         /// drop it). In other words, no assumptions are made that entries in claimable_htlcs point to
1884         /// still-available channels.
1885         fn fail_htlc_backwards_internal(&self, mut channel_state_lock: MutexGuard<ChannelHolder<ChanSigner>>, source: HTLCSource, payment_hash: &PaymentHash, onion_error: HTLCFailReason) {
1886                 //TODO: There is a timing attack here where if a node fails an HTLC back to us they can
1887                 //identify whether we sent it or not based on the (I presume) very different runtime
1888                 //between the branches here. We should make this async and move it into the forward HTLCs
1889                 //timer handling.
1890                 match source {
1891                         HTLCSource::OutboundRoute { ref path, .. } => {
1892                                 log_trace!(self.logger, "Failing outbound payment HTLC with payment_hash {}", log_bytes!(payment_hash.0));
1893                                 mem::drop(channel_state_lock);
1894                                 match &onion_error {
1895                                         &HTLCFailReason::LightningError { ref err } => {
1896 #[cfg(test)]
1897                                                 let (channel_update, payment_retryable, onion_error_code, onion_error_data) = onion_utils::process_onion_failure(&self.secp_ctx, &self.logger, &source, err.data.clone());
1898 #[cfg(not(test))]
1899                                                 let (channel_update, payment_retryable, _, _) = onion_utils::process_onion_failure(&self.secp_ctx, &self.logger, &source, err.data.clone());
1900                                                 // TODO: If we decided to blame ourselves (or one of our channels) in
1901                                                 // process_onion_failure we should close that channel as it implies our
1902                                                 // next-hop is needlessly blaming us!
1903                                                 if let Some(update) = channel_update {
1904                                                         self.channel_state.lock().unwrap().pending_msg_events.push(
1905                                                                 events::MessageSendEvent::PaymentFailureNetworkUpdate {
1906                                                                         update,
1907                                                                 }
1908                                                         );
1909                                                 }
1910                                                 self.pending_events.lock().unwrap().push(
1911                                                         events::Event::PaymentFailed {
1912                                                                 payment_hash: payment_hash.clone(),
1913                                                                 rejected_by_dest: !payment_retryable,
1914 #[cfg(test)]
1915                                                                 error_code: onion_error_code,
1916 #[cfg(test)]
1917                                                                 error_data: onion_error_data
1918                                                         }
1919                                                 );
1920                                         },
1921                                         &HTLCFailReason::Reason {
1922 #[cfg(test)]
1923                                                         ref failure_code,
1924 #[cfg(test)]
1925                                                         ref data,
1926                                                         .. } => {
1927                                                 // we get a fail_malformed_htlc from the first hop
1928                                                 // TODO: We'd like to generate a PaymentFailureNetworkUpdate for temporary
1929                                                 // failures here, but that would be insufficient as get_route
1930                                                 // generally ignores its view of our own channels as we provide them via
1931                                                 // ChannelDetails.
1932                                                 // TODO: For non-temporary failures, we really should be closing the
1933                                                 // channel here as we apparently can't relay through them anyway.
1934                                                 self.pending_events.lock().unwrap().push(
1935                                                         events::Event::PaymentFailed {
1936                                                                 payment_hash: payment_hash.clone(),
1937                                                                 rejected_by_dest: path.len() == 1,
1938 #[cfg(test)]
1939                                                                 error_code: Some(*failure_code),
1940 #[cfg(test)]
1941                                                                 error_data: Some(data.clone()),
1942                                                         }
1943                                                 );
1944                                         }
1945                                 }
1946                         },
1947                         HTLCSource::PreviousHopData(HTLCPreviousHopData { short_channel_id, htlc_id, incoming_packet_shared_secret }) => {
1948                                 let err_packet = match onion_error {
1949                                         HTLCFailReason::Reason { failure_code, data } => {
1950                                                 log_trace!(self.logger, "Failing HTLC with payment_hash {} backwards from us with code {}", log_bytes!(payment_hash.0), failure_code);
1951                                                 let packet = onion_utils::build_failure_packet(&incoming_packet_shared_secret, failure_code, &data[..]).encode();
1952                                                 onion_utils::encrypt_failure_packet(&incoming_packet_shared_secret, &packet)
1953                                         },
1954                                         HTLCFailReason::LightningError { err } => {
1955                                                 log_trace!(self.logger, "Failing HTLC with payment_hash {} backwards with pre-built LightningError", log_bytes!(payment_hash.0));
1956                                                 onion_utils::encrypt_failure_packet(&incoming_packet_shared_secret, &err.data)
1957                                         }
1958                                 };
1959
1960                                 let mut forward_event = None;
1961                                 if channel_state_lock.forward_htlcs.is_empty() {
1962                                         forward_event = Some(Duration::from_millis(MIN_HTLC_RELAY_HOLDING_CELL_MILLIS));
1963                                 }
1964                                 match channel_state_lock.forward_htlcs.entry(short_channel_id) {
1965                                         hash_map::Entry::Occupied(mut entry) => {
1966                                                 entry.get_mut().push(HTLCForwardInfo::FailHTLC { htlc_id, err_packet });
1967                                         },
1968                                         hash_map::Entry::Vacant(entry) => {
1969                                                 entry.insert(vec!(HTLCForwardInfo::FailHTLC { htlc_id, err_packet }));
1970                                         }
1971                                 }
1972                                 mem::drop(channel_state_lock);
1973                                 if let Some(time) = forward_event {
1974                                         let mut pending_events = self.pending_events.lock().unwrap();
1975                                         pending_events.push(events::Event::PendingHTLCsForwardable {
1976                                                 time_forwardable: time
1977                                         });
1978                                 }
1979                         },
1980                 }
1981         }
1982
1983         /// Provides a payment preimage in response to a PaymentReceived event, returning true and
1984         /// generating message events for the net layer to claim the payment, if possible. Thus, you
1985         /// should probably kick the net layer to go send messages if this returns true!
1986         ///
1987         /// You must specify the expected amounts for this HTLC, and we will only claim HTLCs
1988         /// available within a few percent of the expected amount. This is critical for several
1989         /// reasons : a) it avoids providing senders with `proof-of-payment` (in the form of the
1990         /// payment_preimage without having provided the full value and b) it avoids certain
1991         /// privacy-breaking recipient-probing attacks which may reveal payment activity to
1992         /// motivated attackers.
1993         ///
1994         /// Note that the privacy concerns in (b) are not relevant in payments with a payment_secret
1995         /// set. Thus, for such payments we will claim any payments which do not under-pay.
1996         ///
1997         /// May panic if called except in response to a PaymentReceived event.
1998         pub fn claim_funds(&self, payment_preimage: PaymentPreimage, payment_secret: &Option<PaymentSecret>, expected_amount: u64) -> bool {
1999                 let payment_hash = PaymentHash(Sha256::hash(&payment_preimage.0).into_inner());
2000
2001                 let _ = self.total_consistency_lock.read().unwrap();
2002
2003                 let mut channel_state = Some(self.channel_state.lock().unwrap());
2004                 let removed_source = channel_state.as_mut().unwrap().claimable_htlcs.remove(&(payment_hash, *payment_secret));
2005                 if let Some(mut sources) = removed_source {
2006                         assert!(!sources.is_empty());
2007
2008                         // If we are claiming an MPP payment, we have to take special care to ensure that each
2009                         // channel exists before claiming all of the payments (inside one lock).
2010                         // Note that channel existance is sufficient as we should always get a monitor update
2011                         // which will take care of the real HTLC claim enforcement.
2012                         //
2013                         // If we find an HTLC which we would need to claim but for which we do not have a
2014                         // channel, we will fail all parts of the MPP payment. While we could wait and see if
2015                         // the sender retries the already-failed path(s), it should be a pretty rare case where
2016                         // we got all the HTLCs and then a channel closed while we were waiting for the user to
2017                         // provide the preimage, so worrying too much about the optimal handling isn't worth
2018                         // it.
2019
2020                         let (is_mpp, mut valid_mpp) = if let &Some(ref data) = &sources[0].payment_data {
2021                                 assert!(payment_secret.is_some());
2022                                 (true, data.total_msat >= expected_amount)
2023                         } else {
2024                                 assert!(payment_secret.is_none());
2025                                 (false, false)
2026                         };
2027
2028                         for htlc in sources.iter() {
2029                                 if !is_mpp || !valid_mpp { break; }
2030                                 if let None = channel_state.as_ref().unwrap().short_to_id.get(&htlc.prev_hop.short_channel_id) {
2031                                         valid_mpp = false;
2032                                 }
2033                         }
2034
2035                         let mut errs = Vec::new();
2036                         let mut claimed_any_htlcs = false;
2037                         for htlc in sources.drain(..) {
2038                                 if channel_state.is_none() { channel_state = Some(self.channel_state.lock().unwrap()); }
2039                                 if (is_mpp && !valid_mpp) || (!is_mpp && (htlc.value < expected_amount || htlc.value > expected_amount * 2)) {
2040                                         let mut htlc_msat_height_data = byte_utils::be64_to_array(htlc.value).to_vec();
2041                                         htlc_msat_height_data.extend_from_slice(&byte_utils::be32_to_array(
2042                                                 self.latest_block_height.load(Ordering::Acquire) as u32,
2043                                         ));
2044                                         self.fail_htlc_backwards_internal(channel_state.take().unwrap(),
2045                                                                          HTLCSource::PreviousHopData(htlc.prev_hop), &payment_hash,
2046                                                                          HTLCFailReason::Reason { failure_code: 0x4000|15, data: htlc_msat_height_data });
2047                                 } else {
2048                                         match self.claim_funds_from_hop(channel_state.as_mut().unwrap(), htlc.prev_hop, payment_preimage) {
2049                                                 Err(Some(e)) => {
2050                                                         if let msgs::ErrorAction::IgnoreError = e.1.err.action {
2051                                                                 // We got a temporary failure updating monitor, but will claim the
2052                                                                 // HTLC when the monitor updating is restored (or on chain).
2053                                                                 log_error!(self.logger, "Temporary failure claiming HTLC, treating as success: {}", e.1.err.err);
2054                                                                 claimed_any_htlcs = true;
2055                                                         } else { errs.push(e); }
2056                                                 },
2057                                                 Err(None) if is_mpp => unreachable!("We already checked for channel existence, we can't fail here!"),
2058                                                 Err(None) => {
2059                                                         log_warn!(self.logger, "Channel we expected to claim an HTLC from was closed.");
2060                                                 },
2061                                                 Ok(()) => claimed_any_htlcs = true,
2062                                         }
2063                                 }
2064                         }
2065
2066                         // Now that we've done the entire above loop in one lock, we can handle any errors
2067                         // which were generated.
2068                         channel_state.take();
2069
2070                         for (counterparty_node_id, err) in errs.drain(..) {
2071                                 let res: Result<(), _> = Err(err);
2072                                 let _ = handle_error!(self, res, counterparty_node_id);
2073                         }
2074
2075                         claimed_any_htlcs
2076                 } else { false }
2077         }
2078
2079         fn claim_funds_from_hop(&self, channel_state_lock: &mut MutexGuard<ChannelHolder<ChanSigner>>, prev_hop: HTLCPreviousHopData, payment_preimage: PaymentPreimage) -> Result<(), Option<(PublicKey, MsgHandleErrInternal)>> {
2080                 //TODO: Delay the claimed_funds relaying just like we do outbound relay!
2081                 let channel_state = &mut **channel_state_lock;
2082                 let chan_id = match channel_state.short_to_id.get(&prev_hop.short_channel_id) {
2083                         Some(chan_id) => chan_id.clone(),
2084                         None => {
2085                                 return Err(None)
2086                         }
2087                 };
2088
2089                 if let hash_map::Entry::Occupied(mut chan) = channel_state.by_id.entry(chan_id) {
2090                         let was_frozen_for_monitor = chan.get().is_awaiting_monitor_update();
2091                         match chan.get_mut().get_update_fulfill_htlc_and_commit(prev_hop.htlc_id, payment_preimage, &self.logger) {
2092                                 Ok((msgs, monitor_option)) => {
2093                                         if let Some(monitor_update) = monitor_option {
2094                                                 if let Err(e) = self.chain_monitor.update_channel(chan.get().get_funding_txo().unwrap(), monitor_update) {
2095                                                         if was_frozen_for_monitor {
2096                                                                 assert!(msgs.is_none());
2097                                                         } else {
2098                                                                 return Err(Some((chan.get().get_counterparty_node_id(), handle_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::CommitmentFirst, false, msgs.is_some()).unwrap_err())));
2099                                                         }
2100                                                 }
2101                                         }
2102                                         if let Some((msg, commitment_signed)) = msgs {
2103                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
2104                                                         node_id: chan.get().get_counterparty_node_id(),
2105                                                         updates: msgs::CommitmentUpdate {
2106                                                                 update_add_htlcs: Vec::new(),
2107                                                                 update_fulfill_htlcs: vec![msg],
2108                                                                 update_fail_htlcs: Vec::new(),
2109                                                                 update_fail_malformed_htlcs: Vec::new(),
2110                                                                 update_fee: None,
2111                                                                 commitment_signed,
2112                                                         }
2113                                                 });
2114                                         }
2115                                         return Ok(())
2116                                 },
2117                                 Err(e) => {
2118                                         // TODO: Do something with e?
2119                                         // This should only occur if we are claiming an HTLC at the same time as the
2120                                         // HTLC is being failed (eg because a block is being connected and this caused
2121                                         // an HTLC to time out). This should, of course, only occur if the user is the
2122                                         // one doing the claiming (as it being a part of a peer claim would imply we're
2123                                         // about to lose funds) and only if the lock in claim_funds was dropped as a
2124                                         // previous HTLC was failed (thus not for an MPP payment).
2125                                         debug_assert!(false, "This shouldn't be reachable except in absurdly rare cases between monitor updates and HTLC timeouts: {:?}", e);
2126                                         return Err(None)
2127                                 },
2128                         }
2129                 } else { unreachable!(); }
2130         }
2131
2132         fn claim_funds_internal(&self, mut channel_state_lock: MutexGuard<ChannelHolder<ChanSigner>>, source: HTLCSource, payment_preimage: PaymentPreimage) {
2133                 match source {
2134                         HTLCSource::OutboundRoute { .. } => {
2135                                 mem::drop(channel_state_lock);
2136                                 let mut pending_events = self.pending_events.lock().unwrap();
2137                                 pending_events.push(events::Event::PaymentSent {
2138                                         payment_preimage
2139                                 });
2140                         },
2141                         HTLCSource::PreviousHopData(hop_data) => {
2142                                 if let Err((counterparty_node_id, err)) = match self.claim_funds_from_hop(&mut channel_state_lock, hop_data, payment_preimage) {
2143                                         Ok(()) => Ok(()),
2144                                         Err(None) => {
2145                                                 // TODO: There is probably a channel monitor somewhere that needs to
2146                                                 // learn the preimage as the channel already hit the chain and that's
2147                                                 // why it's missing.
2148                                                 Ok(())
2149                                         },
2150                                         Err(Some(res)) => Err(res),
2151                                 } {
2152                                         mem::drop(channel_state_lock);
2153                                         let res: Result<(), _> = Err(err);
2154                                         let _ = handle_error!(self, res, counterparty_node_id);
2155                                 }
2156                         },
2157                 }
2158         }
2159
2160         /// Gets the node_id held by this ChannelManager
2161         pub fn get_our_node_id(&self) -> PublicKey {
2162                 PublicKey::from_secret_key(&self.secp_ctx, &self.our_network_key)
2163         }
2164
2165         /// Restores a single, given channel to normal operation after a
2166         /// ChannelMonitorUpdateErr::TemporaryFailure was returned from a channel monitor update
2167         /// operation.
2168         ///
2169         /// All ChannelMonitor updates up to and including highest_applied_update_id must have been
2170         /// fully committed in every copy of the given channels' ChannelMonitors.
2171         ///
2172         /// Note that there is no effect to calling with a highest_applied_update_id other than the
2173         /// current latest ChannelMonitorUpdate and one call to this function after multiple
2174         /// ChannelMonitorUpdateErr::TemporaryFailures is fine. The highest_applied_update_id field
2175         /// exists largely only to prevent races between this and concurrent update_monitor calls.
2176         ///
2177         /// Thus, the anticipated use is, at a high level:
2178         ///  1) You register a chain::Watch with this ChannelManager,
2179         ///  2) it stores each update to disk, and begins updating any remote (eg watchtower) copies of
2180         ///     said ChannelMonitors as it can, returning ChannelMonitorUpdateErr::TemporaryFailures
2181         ///     any time it cannot do so instantly,
2182         ///  3) update(s) are applied to each remote copy of a ChannelMonitor,
2183         ///  4) once all remote copies are updated, you call this function with the update_id that
2184         ///     completed, and once it is the latest the Channel will be re-enabled.
2185         pub fn channel_monitor_updated(&self, funding_txo: &OutPoint, highest_applied_update_id: u64) {
2186                 let _ = self.total_consistency_lock.read().unwrap();
2187
2188                 let mut close_results = Vec::new();
2189                 let mut htlc_forwards = Vec::new();
2190                 let mut htlc_failures = Vec::new();
2191                 let mut pending_events = Vec::new();
2192
2193                 {
2194                         let mut channel_lock = self.channel_state.lock().unwrap();
2195                         let channel_state = &mut *channel_lock;
2196                         let short_to_id = &mut channel_state.short_to_id;
2197                         let pending_msg_events = &mut channel_state.pending_msg_events;
2198                         let channel = match channel_state.by_id.get_mut(&funding_txo.to_channel_id()) {
2199                                 Some(chan) => chan,
2200                                 None => return,
2201                         };
2202                         if !channel.is_awaiting_monitor_update() || channel.get_latest_monitor_update_id() != highest_applied_update_id {
2203                                 return;
2204                         }
2205
2206                         let (raa, commitment_update, order, pending_forwards, mut pending_failures, needs_broadcast_safe, funding_locked) = channel.monitor_updating_restored(&self.logger);
2207                         if !pending_forwards.is_empty() {
2208                                 htlc_forwards.push((channel.get_short_channel_id().expect("We can't have pending forwards before funding confirmation"), pending_forwards));
2209                         }
2210                         htlc_failures.append(&mut pending_failures);
2211
2212                         macro_rules! handle_cs { () => {
2213                                 if let Some(update) = commitment_update {
2214                                         pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
2215                                                 node_id: channel.get_counterparty_node_id(),
2216                                                 updates: update,
2217                                         });
2218                                 }
2219                         } }
2220                         macro_rules! handle_raa { () => {
2221                                 if let Some(revoke_and_ack) = raa {
2222                                         pending_msg_events.push(events::MessageSendEvent::SendRevokeAndACK {
2223                                                 node_id: channel.get_counterparty_node_id(),
2224                                                 msg: revoke_and_ack,
2225                                         });
2226                                 }
2227                         } }
2228                         match order {
2229                                 RAACommitmentOrder::CommitmentFirst => {
2230                                         handle_cs!();
2231                                         handle_raa!();
2232                                 },
2233                                 RAACommitmentOrder::RevokeAndACKFirst => {
2234                                         handle_raa!();
2235                                         handle_cs!();
2236                                 },
2237                         }
2238                         if needs_broadcast_safe {
2239                                 pending_events.push(events::Event::FundingBroadcastSafe {
2240                                         funding_txo: channel.get_funding_txo().unwrap(),
2241                                         user_channel_id: channel.get_user_id(),
2242                                 });
2243                         }
2244                         if let Some(msg) = funding_locked {
2245                                 pending_msg_events.push(events::MessageSendEvent::SendFundingLocked {
2246                                         node_id: channel.get_counterparty_node_id(),
2247                                         msg,
2248                                 });
2249                                 if let Some(announcement_sigs) = self.get_announcement_sigs(channel) {
2250                                         pending_msg_events.push(events::MessageSendEvent::SendAnnouncementSignatures {
2251                                                 node_id: channel.get_counterparty_node_id(),
2252                                                 msg: announcement_sigs,
2253                                         });
2254                                 }
2255                                 short_to_id.insert(channel.get_short_channel_id().unwrap(), channel.channel_id());
2256                         }
2257                 }
2258
2259                 self.pending_events.lock().unwrap().append(&mut pending_events);
2260
2261                 for failure in htlc_failures.drain(..) {
2262                         self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), failure.0, &failure.1, failure.2);
2263                 }
2264                 self.forward_htlcs(&mut htlc_forwards[..]);
2265
2266                 for res in close_results.drain(..) {
2267                         self.finish_force_close_channel(res);
2268                 }
2269         }
2270
2271         fn internal_open_channel(&self, counterparty_node_id: &PublicKey, their_features: InitFeatures, msg: &msgs::OpenChannel) -> Result<(), MsgHandleErrInternal> {
2272                 if msg.chain_hash != self.genesis_hash {
2273                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Unknown genesis block hash".to_owned(), msg.temporary_channel_id.clone()));
2274                 }
2275
2276                 let channel = Channel::new_from_req(&self.fee_estimator, &self.keys_manager, counterparty_node_id.clone(), their_features, msg, 0, &self.default_configuration)
2277                         .map_err(|e| MsgHandleErrInternal::from_chan_no_close(e, msg.temporary_channel_id))?;
2278                 let mut channel_state_lock = self.channel_state.lock().unwrap();
2279                 let channel_state = &mut *channel_state_lock;
2280                 match channel_state.by_id.entry(channel.channel_id()) {
2281                         hash_map::Entry::Occupied(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("temporary_channel_id collision!".to_owned(), msg.temporary_channel_id.clone())),
2282                         hash_map::Entry::Vacant(entry) => {
2283                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendAcceptChannel {
2284                                         node_id: counterparty_node_id.clone(),
2285                                         msg: channel.get_accept_channel(),
2286                                 });
2287                                 entry.insert(channel);
2288                         }
2289                 }
2290                 Ok(())
2291         }
2292
2293         fn internal_accept_channel(&self, counterparty_node_id: &PublicKey, their_features: InitFeatures, msg: &msgs::AcceptChannel) -> Result<(), MsgHandleErrInternal> {
2294                 let (value, output_script, user_id) = {
2295                         let mut channel_lock = self.channel_state.lock().unwrap();
2296                         let channel_state = &mut *channel_lock;
2297                         match channel_state.by_id.entry(msg.temporary_channel_id) {
2298                                 hash_map::Entry::Occupied(mut chan) => {
2299                                         if chan.get().get_counterparty_node_id() != *counterparty_node_id {
2300                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.temporary_channel_id));
2301                                         }
2302                                         try_chan_entry!(self, chan.get_mut().accept_channel(&msg, &self.default_configuration, their_features), channel_state, chan);
2303                                         (chan.get().get_value_satoshis(), chan.get().get_funding_redeemscript().to_v0_p2wsh(), chan.get().get_user_id())
2304                                 },
2305                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.temporary_channel_id))
2306                         }
2307                 };
2308                 let mut pending_events = self.pending_events.lock().unwrap();
2309                 pending_events.push(events::Event::FundingGenerationReady {
2310                         temporary_channel_id: msg.temporary_channel_id,
2311                         channel_value_satoshis: value,
2312                         output_script: output_script,
2313                         user_channel_id: user_id,
2314                 });
2315                 Ok(())
2316         }
2317
2318         fn internal_funding_created(&self, counterparty_node_id: &PublicKey, msg: &msgs::FundingCreated) -> Result<(), MsgHandleErrInternal> {
2319                 let ((funding_msg, monitor), mut chan) = {
2320                         let mut channel_lock = self.channel_state.lock().unwrap();
2321                         let channel_state = &mut *channel_lock;
2322                         match channel_state.by_id.entry(msg.temporary_channel_id.clone()) {
2323                                 hash_map::Entry::Occupied(mut chan) => {
2324                                         if chan.get().get_counterparty_node_id() != *counterparty_node_id {
2325                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.temporary_channel_id));
2326                                         }
2327                                         (try_chan_entry!(self, chan.get_mut().funding_created(msg, &self.logger), channel_state, chan), chan.remove())
2328                                 },
2329                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.temporary_channel_id))
2330                         }
2331                 };
2332                 // Because we have exclusive ownership of the channel here we can release the channel_state
2333                 // lock before watch_channel
2334                 if let Err(e) = self.chain_monitor.watch_channel(monitor.get_funding_txo().0, monitor) {
2335                         match e {
2336                                 ChannelMonitorUpdateErr::PermanentFailure => {
2337                                         // Note that we reply with the new channel_id in error messages if we gave up on the
2338                                         // channel, not the temporary_channel_id. This is compatible with ourselves, but the
2339                                         // spec is somewhat ambiguous here. Not a huge deal since we'll send error messages for
2340                                         // any messages referencing a previously-closed channel anyway.
2341                                         return Err(MsgHandleErrInternal::from_finish_shutdown("ChannelMonitor storage failure".to_owned(), funding_msg.channel_id, chan.force_shutdown(true), None));
2342                                 },
2343                                 ChannelMonitorUpdateErr::TemporaryFailure => {
2344                                         // There's no problem signing a counterparty's funding transaction if our monitor
2345                                         // hasn't persisted to disk yet - we can't lose money on a transaction that we haven't
2346                                         // accepted payment from yet. We do, however, need to wait to send our funding_locked
2347                                         // until we have persisted our monitor.
2348                                         chan.monitor_update_failed(false, false, Vec::new(), Vec::new());
2349                                 },
2350                         }
2351                 }
2352                 let mut channel_state_lock = self.channel_state.lock().unwrap();
2353                 let channel_state = &mut *channel_state_lock;
2354                 match channel_state.by_id.entry(funding_msg.channel_id) {
2355                         hash_map::Entry::Occupied(_) => {
2356                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Already had channel with the new channel_id".to_owned(), funding_msg.channel_id))
2357                         },
2358                         hash_map::Entry::Vacant(e) => {
2359                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendFundingSigned {
2360                                         node_id: counterparty_node_id.clone(),
2361                                         msg: funding_msg,
2362                                 });
2363                                 e.insert(chan);
2364                         }
2365                 }
2366                 Ok(())
2367         }
2368
2369         fn internal_funding_signed(&self, counterparty_node_id: &PublicKey, msg: &msgs::FundingSigned) -> Result<(), MsgHandleErrInternal> {
2370                 let (funding_txo, user_id) = {
2371                         let mut channel_lock = self.channel_state.lock().unwrap();
2372                         let channel_state = &mut *channel_lock;
2373                         match channel_state.by_id.entry(msg.channel_id) {
2374                                 hash_map::Entry::Occupied(mut chan) => {
2375                                         if chan.get().get_counterparty_node_id() != *counterparty_node_id {
2376                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
2377                                         }
2378                                         let monitor = match chan.get_mut().funding_signed(&msg, &self.logger) {
2379                                                 Ok(update) => update,
2380                                                 Err(e) => try_chan_entry!(self, Err(e), channel_state, chan),
2381                                         };
2382                                         if let Err(e) = self.chain_monitor.watch_channel(chan.get().get_funding_txo().unwrap(), monitor) {
2383                                                 return_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::RevokeAndACKFirst, false, false);
2384                                         }
2385                                         (chan.get().get_funding_txo().unwrap(), chan.get().get_user_id())
2386                                 },
2387                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
2388                         }
2389                 };
2390                 let mut pending_events = self.pending_events.lock().unwrap();
2391                 pending_events.push(events::Event::FundingBroadcastSafe {
2392                         funding_txo: funding_txo,
2393                         user_channel_id: user_id,
2394                 });
2395                 Ok(())
2396         }
2397
2398         fn internal_funding_locked(&self, counterparty_node_id: &PublicKey, msg: &msgs::FundingLocked) -> Result<(), MsgHandleErrInternal> {
2399                 let mut channel_state_lock = self.channel_state.lock().unwrap();
2400                 let channel_state = &mut *channel_state_lock;
2401                 match channel_state.by_id.entry(msg.channel_id) {
2402                         hash_map::Entry::Occupied(mut chan) => {
2403                                 if chan.get().get_counterparty_node_id() != *counterparty_node_id {
2404                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
2405                                 }
2406                                 try_chan_entry!(self, chan.get_mut().funding_locked(&msg), channel_state, chan);
2407                                 if let Some(announcement_sigs) = self.get_announcement_sigs(chan.get()) {
2408                                         log_trace!(self.logger, "Sending announcement_signatures for {} in response to funding_locked", log_bytes!(chan.get().channel_id()));
2409                                         // If we see locking block before receiving remote funding_locked, we broadcast our
2410                                         // announcement_sigs at remote funding_locked reception. If we receive remote
2411                                         // funding_locked before seeing locking block, we broadcast our announcement_sigs at locking
2412                                         // block connection. We should guanrantee to broadcast announcement_sigs to our peer whatever
2413                                         // the order of the events but our peer may not receive it due to disconnection. The specs
2414                                         // lacking an acknowledgement for announcement_sigs we may have to re-send them at peer
2415                                         // connection in the future if simultaneous misses by both peers due to network/hardware
2416                                         // failures is an issue. Note, to achieve its goal, only one of the announcement_sigs needs
2417                                         // to be received, from then sigs are going to be flood to the whole network.
2418                                         channel_state.pending_msg_events.push(events::MessageSendEvent::SendAnnouncementSignatures {
2419                                                 node_id: counterparty_node_id.clone(),
2420                                                 msg: announcement_sigs,
2421                                         });
2422                                 }
2423                                 Ok(())
2424                         },
2425                         hash_map::Entry::Vacant(_) => Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
2426                 }
2427         }
2428
2429         fn internal_shutdown(&self, counterparty_node_id: &PublicKey, msg: &msgs::Shutdown) -> Result<(), MsgHandleErrInternal> {
2430                 let (mut dropped_htlcs, chan_option) = {
2431                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2432                         let channel_state = &mut *channel_state_lock;
2433
2434                         match channel_state.by_id.entry(msg.channel_id.clone()) {
2435                                 hash_map::Entry::Occupied(mut chan_entry) => {
2436                                         if chan_entry.get().get_counterparty_node_id() != *counterparty_node_id {
2437                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
2438                                         }
2439                                         let (shutdown, closing_signed, dropped_htlcs) = try_chan_entry!(self, chan_entry.get_mut().shutdown(&self.fee_estimator, &msg), channel_state, chan_entry);
2440                                         if let Some(msg) = shutdown {
2441                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendShutdown {
2442                                                         node_id: counterparty_node_id.clone(),
2443                                                         msg,
2444                                                 });
2445                                         }
2446                                         if let Some(msg) = closing_signed {
2447                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendClosingSigned {
2448                                                         node_id: counterparty_node_id.clone(),
2449                                                         msg,
2450                                                 });
2451                                         }
2452                                         if chan_entry.get().is_shutdown() {
2453                                                 if let Some(short_id) = chan_entry.get().get_short_channel_id() {
2454                                                         channel_state.short_to_id.remove(&short_id);
2455                                                 }
2456                                                 (dropped_htlcs, Some(chan_entry.remove_entry().1))
2457                                         } else { (dropped_htlcs, None) }
2458                                 },
2459                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
2460                         }
2461                 };
2462                 for htlc_source in dropped_htlcs.drain(..) {
2463                         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() });
2464                 }
2465                 if let Some(chan) = chan_option {
2466                         if let Ok(update) = self.get_channel_update(&chan) {
2467                                 let mut channel_state = self.channel_state.lock().unwrap();
2468                                 channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
2469                                         msg: update
2470                                 });
2471                         }
2472                 }
2473                 Ok(())
2474         }
2475
2476         fn internal_closing_signed(&self, counterparty_node_id: &PublicKey, msg: &msgs::ClosingSigned) -> Result<(), MsgHandleErrInternal> {
2477                 let (tx, chan_option) = {
2478                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2479                         let channel_state = &mut *channel_state_lock;
2480                         match channel_state.by_id.entry(msg.channel_id.clone()) {
2481                                 hash_map::Entry::Occupied(mut chan_entry) => {
2482                                         if chan_entry.get().get_counterparty_node_id() != *counterparty_node_id {
2483                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
2484                                         }
2485                                         let (closing_signed, tx) = try_chan_entry!(self, chan_entry.get_mut().closing_signed(&self.fee_estimator, &msg), channel_state, chan_entry);
2486                                         if let Some(msg) = closing_signed {
2487                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendClosingSigned {
2488                                                         node_id: counterparty_node_id.clone(),
2489                                                         msg,
2490                                                 });
2491                                         }
2492                                         if tx.is_some() {
2493                                                 // We're done with this channel, we've got a signed closing transaction and
2494                                                 // will send the closing_signed back to the remote peer upon return. This
2495                                                 // also implies there are no pending HTLCs left on the channel, so we can
2496                                                 // fully delete it from tracking (the channel monitor is still around to
2497                                                 // watch for old state broadcasts)!
2498                                                 if let Some(short_id) = chan_entry.get().get_short_channel_id() {
2499                                                         channel_state.short_to_id.remove(&short_id);
2500                                                 }
2501                                                 (tx, Some(chan_entry.remove_entry().1))
2502                                         } else { (tx, None) }
2503                                 },
2504                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
2505                         }
2506                 };
2507                 if let Some(broadcast_tx) = tx {
2508                         log_trace!(self.logger, "Broadcast onchain {}", log_tx!(broadcast_tx));
2509                         self.tx_broadcaster.broadcast_transaction(&broadcast_tx);
2510                 }
2511                 if let Some(chan) = chan_option {
2512                         if let Ok(update) = self.get_channel_update(&chan) {
2513                                 let mut channel_state = self.channel_state.lock().unwrap();
2514                                 channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
2515                                         msg: update
2516                                 });
2517                         }
2518                 }
2519                 Ok(())
2520         }
2521
2522         fn internal_update_add_htlc(&self, counterparty_node_id: &PublicKey, msg: &msgs::UpdateAddHTLC) -> Result<(), MsgHandleErrInternal> {
2523                 //TODO: BOLT 4 points out a specific attack where a peer may re-send an onion packet and
2524                 //determine the state of the payment based on our response/if we forward anything/the time
2525                 //we take to respond. We should take care to avoid allowing such an attack.
2526                 //
2527                 //TODO: There exists a further attack where a node may garble the onion data, forward it to
2528                 //us repeatedly garbled in different ways, and compare our error messages, which are
2529                 //encrypted with the same key. It's not immediately obvious how to usefully exploit that,
2530                 //but we should prevent it anyway.
2531
2532                 let (pending_forward_info, mut channel_state_lock) = self.decode_update_add_htlc_onion(msg);
2533                 let channel_state = &mut *channel_state_lock;
2534
2535                 match channel_state.by_id.entry(msg.channel_id) {
2536                         hash_map::Entry::Occupied(mut chan) => {
2537                                 if chan.get().get_counterparty_node_id() != *counterparty_node_id {
2538                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
2539                                 }
2540
2541                                 let create_pending_htlc_status = |chan: &Channel<ChanSigner>, pending_forward_info: PendingHTLCStatus, error_code: u16| {
2542                                         // Ensure error_code has the UPDATE flag set, since by default we send a
2543                                         // channel update along as part of failing the HTLC.
2544                                         assert!((error_code & 0x1000) != 0);
2545                                         // If the update_add is completely bogus, the call will Err and we will close,
2546                                         // but if we've sent a shutdown and they haven't acknowledged it yet, we just
2547                                         // want to reject the new HTLC and fail it backwards instead of forwarding.
2548                                         match pending_forward_info {
2549                                                 PendingHTLCStatus::Forward(PendingHTLCInfo { ref incoming_shared_secret, .. }) => {
2550                                                         let reason = if let Ok(upd) = self.get_channel_update(chan) {
2551                                                                 onion_utils::build_first_hop_failure_packet(incoming_shared_secret, error_code, &{
2552                                                                         let mut res = Vec::with_capacity(8 + 128);
2553                                                                         // TODO: underspecified, follow https://github.com/lightningnetwork/lightning-rfc/issues/791
2554                                                                         res.extend_from_slice(&byte_utils::be16_to_array(0));
2555                                                                         res.extend_from_slice(&upd.encode_with_len()[..]);
2556                                                                         res
2557                                                                 }[..])
2558                                                         } else {
2559                                                                 // The only case where we'd be unable to
2560                                                                 // successfully get a channel update is if the
2561                                                                 // channel isn't in the fully-funded state yet,
2562                                                                 // implying our counterparty is trying to route
2563                                                                 // payments over the channel back to themselves
2564                                                                 // (cause no one else should know the short_id
2565                                                                 // is a lightning channel yet). We should have
2566                                                                 // no problem just calling this
2567                                                                 // unknown_next_peer (0x4000|10).
2568                                                                 onion_utils::build_first_hop_failure_packet(incoming_shared_secret, 0x4000|10, &[])
2569                                                         };
2570                                                         let msg = msgs::UpdateFailHTLC {
2571                                                                 channel_id: msg.channel_id,
2572                                                                 htlc_id: msg.htlc_id,
2573                                                                 reason
2574                                                         };
2575                                                         PendingHTLCStatus::Fail(HTLCFailureMsg::Relay(msg))
2576                                                 },
2577                                                 _ => pending_forward_info
2578                                         }
2579                                 };
2580                                 try_chan_entry!(self, chan.get_mut().update_add_htlc(&msg, pending_forward_info, create_pending_htlc_status, &self.logger), channel_state, chan);
2581                         },
2582                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
2583                 }
2584                 Ok(())
2585         }
2586
2587         fn internal_update_fulfill_htlc(&self, counterparty_node_id: &PublicKey, msg: &msgs::UpdateFulfillHTLC) -> Result<(), MsgHandleErrInternal> {
2588                 let mut channel_lock = self.channel_state.lock().unwrap();
2589                 let htlc_source = {
2590                         let channel_state = &mut *channel_lock;
2591                         match channel_state.by_id.entry(msg.channel_id) {
2592                                 hash_map::Entry::Occupied(mut chan) => {
2593                                         if chan.get().get_counterparty_node_id() != *counterparty_node_id {
2594                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
2595                                         }
2596                                         try_chan_entry!(self, chan.get_mut().update_fulfill_htlc(&msg), channel_state, chan)
2597                                 },
2598                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
2599                         }
2600                 };
2601                 self.claim_funds_internal(channel_lock, htlc_source, msg.payment_preimage.clone());
2602                 Ok(())
2603         }
2604
2605         fn internal_update_fail_htlc(&self, counterparty_node_id: &PublicKey, msg: &msgs::UpdateFailHTLC) -> Result<(), MsgHandleErrInternal> {
2606                 let mut channel_lock = self.channel_state.lock().unwrap();
2607                 let channel_state = &mut *channel_lock;
2608                 match channel_state.by_id.entry(msg.channel_id) {
2609                         hash_map::Entry::Occupied(mut chan) => {
2610                                 if chan.get().get_counterparty_node_id() != *counterparty_node_id {
2611                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
2612                                 }
2613                                 try_chan_entry!(self, chan.get_mut().update_fail_htlc(&msg, HTLCFailReason::LightningError { err: msg.reason.clone() }), channel_state, chan);
2614                         },
2615                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
2616                 }
2617                 Ok(())
2618         }
2619
2620         fn internal_update_fail_malformed_htlc(&self, counterparty_node_id: &PublicKey, msg: &msgs::UpdateFailMalformedHTLC) -> Result<(), MsgHandleErrInternal> {
2621                 let mut channel_lock = self.channel_state.lock().unwrap();
2622                 let channel_state = &mut *channel_lock;
2623                 match channel_state.by_id.entry(msg.channel_id) {
2624                         hash_map::Entry::Occupied(mut chan) => {
2625                                 if chan.get().get_counterparty_node_id() != *counterparty_node_id {
2626                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
2627                                 }
2628                                 if (msg.failure_code & 0x8000) == 0 {
2629                                         let chan_err: ChannelError = ChannelError::Close("Got update_fail_malformed_htlc with BADONION not set".to_owned());
2630                                         try_chan_entry!(self, Err(chan_err), channel_state, chan);
2631                                 }
2632                                 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);
2633                                 Ok(())
2634                         },
2635                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
2636                 }
2637         }
2638
2639         fn internal_commitment_signed(&self, counterparty_node_id: &PublicKey, msg: &msgs::CommitmentSigned) -> Result<(), MsgHandleErrInternal> {
2640                 let mut channel_state_lock = self.channel_state.lock().unwrap();
2641                 let channel_state = &mut *channel_state_lock;
2642                 match channel_state.by_id.entry(msg.channel_id) {
2643                         hash_map::Entry::Occupied(mut chan) => {
2644                                 if chan.get().get_counterparty_node_id() != *counterparty_node_id {
2645                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
2646                                 }
2647                                 let (revoke_and_ack, commitment_signed, closing_signed, monitor_update) =
2648                                         match chan.get_mut().commitment_signed(&msg, &self.fee_estimator, &self.logger) {
2649                                                 Err((None, e)) => try_chan_entry!(self, Err(e), channel_state, chan),
2650                                                 Err((Some(update), e)) => {
2651                                                         assert!(chan.get().is_awaiting_monitor_update());
2652                                                         let _ = self.chain_monitor.update_channel(chan.get().get_funding_txo().unwrap(), update);
2653                                                         try_chan_entry!(self, Err(e), channel_state, chan);
2654                                                         unreachable!();
2655                                                 },
2656                                                 Ok(res) => res
2657                                         };
2658                                 if let Err(e) = self.chain_monitor.update_channel(chan.get().get_funding_txo().unwrap(), monitor_update) {
2659                                         return_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::RevokeAndACKFirst, true, commitment_signed.is_some());
2660                                         //TODO: Rebroadcast closing_signed if present on monitor update restoration
2661                                 }
2662                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendRevokeAndACK {
2663                                         node_id: counterparty_node_id.clone(),
2664                                         msg: revoke_and_ack,
2665                                 });
2666                                 if let Some(msg) = commitment_signed {
2667                                         channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
2668                                                 node_id: counterparty_node_id.clone(),
2669                                                 updates: msgs::CommitmentUpdate {
2670                                                         update_add_htlcs: Vec::new(),
2671                                                         update_fulfill_htlcs: Vec::new(),
2672                                                         update_fail_htlcs: Vec::new(),
2673                                                         update_fail_malformed_htlcs: Vec::new(),
2674                                                         update_fee: None,
2675                                                         commitment_signed: msg,
2676                                                 },
2677                                         });
2678                                 }
2679                                 if let Some(msg) = closing_signed {
2680                                         channel_state.pending_msg_events.push(events::MessageSendEvent::SendClosingSigned {
2681                                                 node_id: counterparty_node_id.clone(),
2682                                                 msg,
2683                                         });
2684                                 }
2685                                 Ok(())
2686                         },
2687                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
2688                 }
2689         }
2690
2691         #[inline]
2692         fn forward_htlcs(&self, per_source_pending_forwards: &mut [(u64, Vec<(PendingHTLCInfo, u64)>)]) {
2693                 for &mut (prev_short_channel_id, ref mut pending_forwards) in per_source_pending_forwards {
2694                         let mut forward_event = None;
2695                         if !pending_forwards.is_empty() {
2696                                 let mut channel_state = self.channel_state.lock().unwrap();
2697                                 if channel_state.forward_htlcs.is_empty() {
2698                                         forward_event = Some(Duration::from_millis(MIN_HTLC_RELAY_HOLDING_CELL_MILLIS))
2699                                 }
2700                                 for (forward_info, prev_htlc_id) in pending_forwards.drain(..) {
2701                                         match channel_state.forward_htlcs.entry(match forward_info.routing {
2702                                                         PendingHTLCRouting::Forward { short_channel_id, .. } => short_channel_id,
2703                                                         PendingHTLCRouting::Receive { .. } => 0,
2704                                         }) {
2705                                                 hash_map::Entry::Occupied(mut entry) => {
2706                                                         entry.get_mut().push(HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info });
2707                                                 },
2708                                                 hash_map::Entry::Vacant(entry) => {
2709                                                         entry.insert(vec!(HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info }));
2710                                                 }
2711                                         }
2712                                 }
2713                         }
2714                         match forward_event {
2715                                 Some(time) => {
2716                                         let mut pending_events = self.pending_events.lock().unwrap();
2717                                         pending_events.push(events::Event::PendingHTLCsForwardable {
2718                                                 time_forwardable: time
2719                                         });
2720                                 }
2721                                 None => {},
2722                         }
2723                 }
2724         }
2725
2726         fn internal_revoke_and_ack(&self, counterparty_node_id: &PublicKey, msg: &msgs::RevokeAndACK) -> Result<(), MsgHandleErrInternal> {
2727                 let mut htlcs_to_fail = Vec::new();
2728                 let res = loop {
2729                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2730                         let channel_state = &mut *channel_state_lock;
2731                         match channel_state.by_id.entry(msg.channel_id) {
2732                                 hash_map::Entry::Occupied(mut chan) => {
2733                                         if chan.get().get_counterparty_node_id() != *counterparty_node_id {
2734                                                 break Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
2735                                         }
2736                                         let was_frozen_for_monitor = chan.get().is_awaiting_monitor_update();
2737                                         let (commitment_update, pending_forwards, pending_failures, closing_signed, monitor_update, htlcs_to_fail_in) =
2738                                                 break_chan_entry!(self, chan.get_mut().revoke_and_ack(&msg, &self.fee_estimator, &self.logger), channel_state, chan);
2739                                         htlcs_to_fail = htlcs_to_fail_in;
2740                                         if let Err(e) = self.chain_monitor.update_channel(chan.get().get_funding_txo().unwrap(), monitor_update) {
2741                                                 if was_frozen_for_monitor {
2742                                                         assert!(commitment_update.is_none() && closing_signed.is_none() && pending_forwards.is_empty() && pending_failures.is_empty());
2743                                                         break Err(MsgHandleErrInternal::ignore_no_close("Previous monitor update failure prevented responses to RAA".to_owned()));
2744                                                 } else {
2745                                                         if let Err(e) = handle_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::CommitmentFirst, false, commitment_update.is_some(), pending_forwards, pending_failures) {
2746                                                                 break Err(e);
2747                                                         } else { unreachable!(); }
2748                                                 }
2749                                         }
2750                                         if let Some(updates) = commitment_update {
2751                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
2752                                                         node_id: counterparty_node_id.clone(),
2753                                                         updates,
2754                                                 });
2755                                         }
2756                                         if let Some(msg) = closing_signed {
2757                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendClosingSigned {
2758                                                         node_id: counterparty_node_id.clone(),
2759                                                         msg,
2760                                                 });
2761                                         }
2762                                         break Ok((pending_forwards, pending_failures, chan.get().get_short_channel_id().expect("RAA should only work on a short-id-available channel")))
2763                                 },
2764                                 hash_map::Entry::Vacant(_) => break Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
2765                         }
2766                 };
2767                 self.fail_holding_cell_htlcs(htlcs_to_fail, msg.channel_id);
2768                 match res {
2769                         Ok((pending_forwards, mut pending_failures, short_channel_id)) => {
2770                                 for failure in pending_failures.drain(..) {
2771                                         self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), failure.0, &failure.1, failure.2);
2772                                 }
2773                                 self.forward_htlcs(&mut [(short_channel_id, pending_forwards)]);
2774                                 Ok(())
2775                         },
2776                         Err(e) => Err(e)
2777                 }
2778         }
2779
2780         fn internal_update_fee(&self, counterparty_node_id: &PublicKey, msg: &msgs::UpdateFee) -> Result<(), MsgHandleErrInternal> {
2781                 let mut channel_lock = self.channel_state.lock().unwrap();
2782                 let channel_state = &mut *channel_lock;
2783                 match channel_state.by_id.entry(msg.channel_id) {
2784                         hash_map::Entry::Occupied(mut chan) => {
2785                                 if chan.get().get_counterparty_node_id() != *counterparty_node_id {
2786                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
2787                                 }
2788                                 try_chan_entry!(self, chan.get_mut().update_fee(&self.fee_estimator, &msg), channel_state, chan);
2789                         },
2790                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
2791                 }
2792                 Ok(())
2793         }
2794
2795         fn internal_announcement_signatures(&self, counterparty_node_id: &PublicKey, msg: &msgs::AnnouncementSignatures) -> Result<(), MsgHandleErrInternal> {
2796                 let mut channel_state_lock = self.channel_state.lock().unwrap();
2797                 let channel_state = &mut *channel_state_lock;
2798
2799                 match channel_state.by_id.entry(msg.channel_id) {
2800                         hash_map::Entry::Occupied(mut chan) => {
2801                                 if chan.get().get_counterparty_node_id() != *counterparty_node_id {
2802                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
2803                                 }
2804                                 if !chan.get().is_usable() {
2805                                         return Err(MsgHandleErrInternal::from_no_close(LightningError{err: "Got an announcement_signatures before we were ready for it".to_owned(), action: msgs::ErrorAction::IgnoreError}));
2806                                 }
2807
2808                                 let our_node_id = self.get_our_node_id();
2809                                 let (announcement, our_bitcoin_sig) =
2810                                         try_chan_entry!(self, chan.get_mut().get_channel_announcement(our_node_id.clone(), self.genesis_hash.clone()), channel_state, chan);
2811
2812                                 let were_node_one = announcement.node_id_1 == our_node_id;
2813                                 let msghash = hash_to_message!(&Sha256dHash::hash(&announcement.encode()[..])[..]);
2814                                 {
2815                                         let their_node_key = if were_node_one { &announcement.node_id_2 } else { &announcement.node_id_1 };
2816                                         let their_bitcoin_key = if were_node_one { &announcement.bitcoin_key_2 } else { &announcement.bitcoin_key_1 };
2817                                         match (self.secp_ctx.verify(&msghash, &msg.node_signature, their_node_key),
2818                                                    self.secp_ctx.verify(&msghash, &msg.bitcoin_signature, their_bitcoin_key)) {
2819                                                 (Err(e), _) => {
2820                                                         let chan_err: ChannelError = ChannelError::Close(format!("Bad announcement_signatures. Failed to verify node_signature: {:?}. Maybe using different node_secret for transport and routing msg? UnsignedChannelAnnouncement used for verification is {:?}. their_node_key is {:?}", e, &announcement, their_node_key));
2821                                                         try_chan_entry!(self, Err(chan_err), channel_state, chan);
2822                                                 },
2823                                                 (_, Err(e)) => {
2824                                                         let chan_err: ChannelError = ChannelError::Close(format!("Bad announcement_signatures. Failed to verify bitcoin_signature: {:?}. UnsignedChannelAnnouncement used for verification is {:?}. their_bitcoin_key is ({:?})", e, &announcement, their_bitcoin_key));
2825                                                         try_chan_entry!(self, Err(chan_err), channel_state, chan);
2826                                                 },
2827                                                 _ => {}
2828                                         }
2829                                 }
2830
2831                                 let our_node_sig = self.secp_ctx.sign(&msghash, &self.our_network_key);
2832
2833                                 channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelAnnouncement {
2834                                         msg: msgs::ChannelAnnouncement {
2835                                                 node_signature_1: if were_node_one { our_node_sig } else { msg.node_signature },
2836                                                 node_signature_2: if were_node_one { msg.node_signature } else { our_node_sig },
2837                                                 bitcoin_signature_1: if were_node_one { our_bitcoin_sig } else { msg.bitcoin_signature },
2838                                                 bitcoin_signature_2: if were_node_one { msg.bitcoin_signature } else { our_bitcoin_sig },
2839                                                 contents: announcement,
2840                                         },
2841                                         update_msg: self.get_channel_update(chan.get()).unwrap(), // can only fail if we're not in a ready state
2842                                 });
2843                         },
2844                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
2845                 }
2846                 Ok(())
2847         }
2848
2849         fn internal_channel_reestablish(&self, counterparty_node_id: &PublicKey, msg: &msgs::ChannelReestablish) -> Result<(), MsgHandleErrInternal> {
2850                 let mut channel_state_lock = self.channel_state.lock().unwrap();
2851                 let channel_state = &mut *channel_state_lock;
2852
2853                 match channel_state.by_id.entry(msg.channel_id) {
2854                         hash_map::Entry::Occupied(mut chan) => {
2855                                 if chan.get().get_counterparty_node_id() != *counterparty_node_id {
2856                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
2857                                 }
2858                                 // Currently, we expect all holding cell update_adds to be dropped on peer
2859                                 // disconnect, so Channel's reestablish will never hand us any holding cell
2860                                 // freed HTLCs to fail backwards. If in the future we no longer drop pending
2861                                 // add-HTLCs on disconnect, we may be handed HTLCs to fail backwards here.
2862                                 let (funding_locked, revoke_and_ack, commitment_update, monitor_update_opt, mut order, shutdown) =
2863                                         try_chan_entry!(self, chan.get_mut().channel_reestablish(msg, &self.logger), channel_state, chan);
2864                                 if let Some(monitor_update) = monitor_update_opt {
2865                                         if let Err(e) = self.chain_monitor.update_channel(chan.get().get_funding_txo().unwrap(), monitor_update) {
2866                                                 // channel_reestablish doesn't guarantee the order it returns is sensical
2867                                                 // for the messages it returns, but if we're setting what messages to
2868                                                 // re-transmit on monitor update success, we need to make sure it is sane.
2869                                                 if revoke_and_ack.is_none() {
2870                                                         order = RAACommitmentOrder::CommitmentFirst;
2871                                                 }
2872                                                 if commitment_update.is_none() {
2873                                                         order = RAACommitmentOrder::RevokeAndACKFirst;
2874                                                 }
2875                                                 return_monitor_err!(self, e, channel_state, chan, order, revoke_and_ack.is_some(), commitment_update.is_some());
2876                                                 //TODO: Resend the funding_locked if needed once we get the monitor running again
2877                                         }
2878                                 }
2879                                 if let Some(msg) = funding_locked {
2880                                         channel_state.pending_msg_events.push(events::MessageSendEvent::SendFundingLocked {
2881                                                 node_id: counterparty_node_id.clone(),
2882                                                 msg
2883                                         });
2884                                 }
2885                                 macro_rules! send_raa { () => {
2886                                         if let Some(msg) = revoke_and_ack {
2887                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendRevokeAndACK {
2888                                                         node_id: counterparty_node_id.clone(),
2889                                                         msg
2890                                                 });
2891                                         }
2892                                 } }
2893                                 macro_rules! send_cu { () => {
2894                                         if let Some(updates) = commitment_update {
2895                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
2896                                                         node_id: counterparty_node_id.clone(),
2897                                                         updates
2898                                                 });
2899                                         }
2900                                 } }
2901                                 match order {
2902                                         RAACommitmentOrder::RevokeAndACKFirst => {
2903                                                 send_raa!();
2904                                                 send_cu!();
2905                                         },
2906                                         RAACommitmentOrder::CommitmentFirst => {
2907                                                 send_cu!();
2908                                                 send_raa!();
2909                                         },
2910                                 }
2911                                 if let Some(msg) = shutdown {
2912                                         channel_state.pending_msg_events.push(events::MessageSendEvent::SendShutdown {
2913                                                 node_id: counterparty_node_id.clone(),
2914                                                 msg,
2915                                         });
2916                                 }
2917                                 Ok(())
2918                         },
2919                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
2920                 }
2921         }
2922
2923         /// Begin Update fee process. Allowed only on an outbound channel.
2924         /// If successful, will generate a UpdateHTLCs event, so you should probably poll
2925         /// PeerManager::process_events afterwards.
2926         /// Note: This API is likely to change!
2927         /// (C-not exported) Cause its doc(hidden) anyway
2928         #[doc(hidden)]
2929         pub fn update_fee(&self, channel_id: [u8;32], feerate_per_kw: u32) -> Result<(), APIError> {
2930                 let _ = self.total_consistency_lock.read().unwrap();
2931                 let counterparty_node_id;
2932                 let err: Result<(), _> = loop {
2933                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2934                         let channel_state = &mut *channel_state_lock;
2935
2936                         match channel_state.by_id.entry(channel_id) {
2937                                 hash_map::Entry::Vacant(_) => return Err(APIError::APIMisuseError{err: format!("Failed to find corresponding channel for id {}", channel_id.to_hex())}),
2938                                 hash_map::Entry::Occupied(mut chan) => {
2939                                         if !chan.get().is_outbound() {
2940                                                 return Err(APIError::APIMisuseError{err: "update_fee cannot be sent for an inbound channel".to_owned()});
2941                                         }
2942                                         if chan.get().is_awaiting_monitor_update() {
2943                                                 return Err(APIError::MonitorUpdateFailed);
2944                                         }
2945                                         if !chan.get().is_live() {
2946                                                 return Err(APIError::ChannelUnavailable{err: "Channel is either not yet fully established or peer is currently disconnected".to_owned()});
2947                                         }
2948                                         counterparty_node_id = chan.get().get_counterparty_node_id();
2949                                         if let Some((update_fee, commitment_signed, monitor_update)) =
2950                                                         break_chan_entry!(self, chan.get_mut().send_update_fee_and_commit(feerate_per_kw, &self.logger), channel_state, chan)
2951                                         {
2952                                                 if let Err(_e) = self.chain_monitor.update_channel(chan.get().get_funding_txo().unwrap(), monitor_update) {
2953                                                         unimplemented!();
2954                                                 }
2955                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
2956                                                         node_id: chan.get().get_counterparty_node_id(),
2957                                                         updates: msgs::CommitmentUpdate {
2958                                                                 update_add_htlcs: Vec::new(),
2959                                                                 update_fulfill_htlcs: Vec::new(),
2960                                                                 update_fail_htlcs: Vec::new(),
2961                                                                 update_fail_malformed_htlcs: Vec::new(),
2962                                                                 update_fee: Some(update_fee),
2963                                                                 commitment_signed,
2964                                                         },
2965                                                 });
2966                                         }
2967                                 },
2968                         }
2969                         return Ok(())
2970                 };
2971
2972                 match handle_error!(self, err, counterparty_node_id) {
2973                         Ok(_) => unreachable!(),
2974                         Err(e) => { Err(APIError::APIMisuseError { err: e.err })}
2975                 }
2976         }
2977
2978         /// Process pending events from the `chain::Watch`.
2979         fn process_pending_monitor_events(&self) {
2980                 let mut failed_channels = Vec::new();
2981                 {
2982                         for monitor_event in self.chain_monitor.release_pending_monitor_events() {
2983                                 match monitor_event {
2984                                         MonitorEvent::HTLCEvent(htlc_update) => {
2985                                                 if let Some(preimage) = htlc_update.payment_preimage {
2986                                                         log_trace!(self.logger, "Claiming HTLC with preimage {} from our monitor", log_bytes!(preimage.0));
2987                                                         self.claim_funds_internal(self.channel_state.lock().unwrap(), htlc_update.source, preimage);
2988                                                 } else {
2989                                                         log_trace!(self.logger, "Failing HTLC with hash {} from our monitor", log_bytes!(htlc_update.payment_hash.0));
2990                                                         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() });
2991                                                 }
2992                                         },
2993                                         MonitorEvent::CommitmentTxBroadcasted(funding_outpoint) => {
2994                                                 let mut channel_lock = self.channel_state.lock().unwrap();
2995                                                 let channel_state = &mut *channel_lock;
2996                                                 let by_id = &mut channel_state.by_id;
2997                                                 let short_to_id = &mut channel_state.short_to_id;
2998                                                 let pending_msg_events = &mut channel_state.pending_msg_events;
2999                                                 if let Some(mut chan) = by_id.remove(&funding_outpoint.to_channel_id()) {
3000                                                         if let Some(short_id) = chan.get_short_channel_id() {
3001                                                                 short_to_id.remove(&short_id);
3002                                                         }
3003                                                         failed_channels.push(chan.force_shutdown(false));
3004                                                         if let Ok(update) = self.get_channel_update(&chan) {
3005                                                                 pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
3006                                                                         msg: update
3007                                                                 });
3008                                                         }
3009                                                 }
3010                                         },
3011                                 }
3012                         }
3013                 }
3014
3015                 for failure in failed_channels.drain(..) {
3016                         self.finish_force_close_channel(failure);
3017                 }
3018         }
3019 }
3020
3021 impl<ChanSigner: ChannelKeys, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> MessageSendEventsProvider for ChannelManager<ChanSigner, M, T, K, F, L>
3022         where M::Target: chain::Watch<Keys=ChanSigner>,
3023         T::Target: BroadcasterInterface,
3024         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
3025         F::Target: FeeEstimator,
3026                                 L::Target: Logger,
3027 {
3028         fn get_and_clear_pending_msg_events(&self) -> Vec<MessageSendEvent> {
3029                 //TODO: This behavior should be documented. It's non-intuitive that we query
3030                 // ChannelMonitors when clearing other events.
3031                 self.process_pending_monitor_events();
3032
3033                 let mut ret = Vec::new();
3034                 let mut channel_state = self.channel_state.lock().unwrap();
3035                 mem::swap(&mut ret, &mut channel_state.pending_msg_events);
3036                 ret
3037         }
3038 }
3039
3040 impl<ChanSigner: ChannelKeys, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> EventsProvider for ChannelManager<ChanSigner, M, T, K, F, L>
3041         where M::Target: chain::Watch<Keys=ChanSigner>,
3042         T::Target: BroadcasterInterface,
3043         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
3044         F::Target: FeeEstimator,
3045                                 L::Target: Logger,
3046 {
3047         fn get_and_clear_pending_events(&self) -> Vec<Event> {
3048                 //TODO: This behavior should be documented. It's non-intuitive that we query
3049                 // ChannelMonitors when clearing other events.
3050                 self.process_pending_monitor_events();
3051
3052                 let mut ret = Vec::new();
3053                 let mut pending_events = self.pending_events.lock().unwrap();
3054                 mem::swap(&mut ret, &mut *pending_events);
3055                 ret
3056         }
3057 }
3058
3059 impl<ChanSigner: ChannelKeys, M: Deref + Sync + Send, T: Deref + Sync + Send, K: Deref + Sync + Send, F: Deref + Sync + Send, L: Deref + Sync + Send>
3060         ChainListener for ChannelManager<ChanSigner, M, T, K, F, L>
3061         where M::Target: chain::Watch<Keys=ChanSigner>,
3062         T::Target: BroadcasterInterface,
3063         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
3064         F::Target: FeeEstimator,
3065                                 L::Target: Logger,
3066 {
3067         fn block_connected(&self, header: &BlockHeader, txdata: &[(usize, &Transaction)], height: u32) {
3068                 let header_hash = header.block_hash();
3069                 log_trace!(self.logger, "Block {} at height {} connected", header_hash, height);
3070                 let _ = self.total_consistency_lock.read().unwrap();
3071                 let mut failed_channels = Vec::new();
3072                 let mut timed_out_htlcs = Vec::new();
3073                 {
3074                         let mut channel_lock = self.channel_state.lock().unwrap();
3075                         let channel_state = &mut *channel_lock;
3076                         let short_to_id = &mut channel_state.short_to_id;
3077                         let pending_msg_events = &mut channel_state.pending_msg_events;
3078                         channel_state.by_id.retain(|_, channel| {
3079                                 let res = channel.block_connected(header, txdata, height);
3080                                 if let Ok((chan_res, mut timed_out_pending_htlcs)) = res {
3081                                         for (source, payment_hash) in timed_out_pending_htlcs.drain(..) {
3082                                                 let chan_update = self.get_channel_update(&channel).map(|u| u.encode_with_len()).unwrap(); // Cannot add/recv HTLCs before we have a short_id so unwrap is safe
3083                                                 timed_out_htlcs.push((source, payment_hash,  HTLCFailReason::Reason {
3084                                                         failure_code: 0x1000 | 14, // expiry_too_soon, or at least it is now
3085                                                         data: chan_update,
3086                                                 }));
3087                                         }
3088                                         if let Some(funding_locked) = chan_res {
3089                                                 pending_msg_events.push(events::MessageSendEvent::SendFundingLocked {
3090                                                         node_id: channel.get_counterparty_node_id(),
3091                                                         msg: funding_locked,
3092                                                 });
3093                                                 if let Some(announcement_sigs) = self.get_announcement_sigs(channel) {
3094                                                         log_trace!(self.logger, "Sending funding_locked and announcement_signatures for {}", log_bytes!(channel.channel_id()));
3095                                                         pending_msg_events.push(events::MessageSendEvent::SendAnnouncementSignatures {
3096                                                                 node_id: channel.get_counterparty_node_id(),
3097                                                                 msg: announcement_sigs,
3098                                                         });
3099                                                 } else {
3100                                                         log_trace!(self.logger, "Sending funding_locked WITHOUT announcement_signatures for {}", log_bytes!(channel.channel_id()));
3101                                                 }
3102                                                 short_to_id.insert(channel.get_short_channel_id().unwrap(), channel.channel_id());
3103                                         }
3104                                 } else if let Err(e) = res {
3105                                         pending_msg_events.push(events::MessageSendEvent::HandleError {
3106                                                 node_id: channel.get_counterparty_node_id(),
3107                                                 action: msgs::ErrorAction::SendErrorMessage { msg: e },
3108                                         });
3109                                         return false;
3110                                 }
3111                                 if let Some(funding_txo) = channel.get_funding_txo() {
3112                                         for &(_, tx) in txdata.iter() {
3113                                                 for inp in tx.input.iter() {
3114                                                         if inp.previous_output == funding_txo.into_bitcoin_outpoint() {
3115                                                                 log_trace!(self.logger, "Detected channel-closing tx {} spending {}:{}, closing channel {}", tx.txid(), inp.previous_output.txid, inp.previous_output.vout, log_bytes!(channel.channel_id()));
3116                                                                 if let Some(short_id) = channel.get_short_channel_id() {
3117                                                                         short_to_id.remove(&short_id);
3118                                                                 }
3119                                                                 // It looks like our counterparty went on-chain. We go ahead and
3120                                                                 // broadcast our latest local state as well here, just in case its
3121                                                                 // some kind of SPV attack, though we expect these to be dropped.
3122                                                                 failed_channels.push(channel.force_shutdown(true));
3123                                                                 if let Ok(update) = self.get_channel_update(&channel) {
3124                                                                         pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
3125                                                                                 msg: update
3126                                                                         });
3127                                                                 }
3128                                                                 return false;
3129                                                         }
3130                                                 }
3131                                         }
3132                                 }
3133                                 true
3134                         });
3135
3136                         channel_state.claimable_htlcs.retain(|&(ref payment_hash, _), htlcs| {
3137                                 htlcs.retain(|htlc| {
3138                                         // If height is approaching the number of blocks we think it takes us to get
3139                                         // our commitment transaction confirmed before the HTLC expires, plus the
3140                                         // number of blocks we generally consider it to take to do a commitment update,
3141                                         // just give up on it and fail the HTLC.
3142                                         if height >= htlc.cltv_expiry - HTLC_FAIL_BACK_BUFFER {
3143                                                 let mut htlc_msat_height_data = byte_utils::be64_to_array(htlc.value).to_vec();
3144                                                 htlc_msat_height_data.extend_from_slice(&byte_utils::be32_to_array(height));
3145                                                 timed_out_htlcs.push((HTLCSource::PreviousHopData(htlc.prev_hop.clone()), payment_hash.clone(), HTLCFailReason::Reason {
3146                                                         failure_code: 0x4000 | 15,
3147                                                         data: htlc_msat_height_data
3148                                                 }));
3149                                                 false
3150                                         } else { true }
3151                                 });
3152                                 !htlcs.is_empty() // Only retain this entry if htlcs has at least one entry.
3153                         });
3154                 }
3155                 for failure in failed_channels.drain(..) {
3156                         self.finish_force_close_channel(failure);
3157                 }
3158
3159                 for (source, payment_hash, reason) in timed_out_htlcs.drain(..) {
3160                         self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), source, &payment_hash, reason);
3161                 }
3162                 self.latest_block_height.store(height as usize, Ordering::Release);
3163                 *self.last_block_hash.try_lock().expect("block_(dis)connected must not be called in parallel") = header_hash;
3164                 loop {
3165                         // Update last_node_announcement_serial to be the max of its current value and the
3166                         // block timestamp. This should keep us close to the current time without relying on
3167                         // having an explicit local time source.
3168                         // Just in case we end up in a race, we loop until we either successfully update
3169                         // last_node_announcement_serial or decide we don't need to.
3170                         let old_serial = self.last_node_announcement_serial.load(Ordering::Acquire);
3171                         if old_serial >= header.time as usize { break; }
3172                         if self.last_node_announcement_serial.compare_exchange(old_serial, header.time as usize, Ordering::AcqRel, Ordering::Relaxed).is_ok() {
3173                                 break;
3174                         }
3175                 }
3176         }
3177
3178         /// We force-close the channel without letting our counterparty participate in the shutdown
3179         fn block_disconnected(&self, header: &BlockHeader, _: u32) {
3180                 let _ = self.total_consistency_lock.read().unwrap();
3181                 let mut failed_channels = Vec::new();
3182                 {
3183                         let mut channel_lock = self.channel_state.lock().unwrap();
3184                         let channel_state = &mut *channel_lock;
3185                         let short_to_id = &mut channel_state.short_to_id;
3186                         let pending_msg_events = &mut channel_state.pending_msg_events;
3187                         channel_state.by_id.retain(|_,  v| {
3188                                 if v.block_disconnected(header) {
3189                                         if let Some(short_id) = v.get_short_channel_id() {
3190                                                 short_to_id.remove(&short_id);
3191                                         }
3192                                         failed_channels.push(v.force_shutdown(true));
3193                                         if let Ok(update) = self.get_channel_update(&v) {
3194                                                 pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
3195                                                         msg: update
3196                                                 });
3197                                         }
3198                                         false
3199                                 } else {
3200                                         true
3201                                 }
3202                         });
3203                 }
3204                 for failure in failed_channels.drain(..) {
3205                         self.finish_force_close_channel(failure);
3206                 }
3207                 self.latest_block_height.fetch_sub(1, Ordering::AcqRel);
3208                 *self.last_block_hash.try_lock().expect("block_(dis)connected must not be called in parallel") = header.block_hash();
3209         }
3210 }
3211
3212 impl<ChanSigner: ChannelKeys, M: Deref + Sync + Send, T: Deref + Sync + Send, K: Deref + Sync + Send, F: Deref + Sync + Send, L: Deref + Sync + Send>
3213         ChannelMessageHandler for ChannelManager<ChanSigner, M, T, K, F, L>
3214         where M::Target: chain::Watch<Keys=ChanSigner>,
3215         T::Target: BroadcasterInterface,
3216         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
3217         F::Target: FeeEstimator,
3218         L::Target: Logger,
3219 {
3220         fn handle_open_channel(&self, counterparty_node_id: &PublicKey, their_features: InitFeatures, msg: &msgs::OpenChannel) {
3221                 let _ = self.total_consistency_lock.read().unwrap();
3222                 let _ = handle_error!(self, self.internal_open_channel(counterparty_node_id, their_features, msg), *counterparty_node_id);
3223         }
3224
3225         fn handle_accept_channel(&self, counterparty_node_id: &PublicKey, their_features: InitFeatures, msg: &msgs::AcceptChannel) {
3226                 let _ = self.total_consistency_lock.read().unwrap();
3227                 let _ = handle_error!(self, self.internal_accept_channel(counterparty_node_id, their_features, msg), *counterparty_node_id);
3228         }
3229
3230         fn handle_funding_created(&self, counterparty_node_id: &PublicKey, msg: &msgs::FundingCreated) {
3231                 let _ = self.total_consistency_lock.read().unwrap();
3232                 let _ = handle_error!(self, self.internal_funding_created(counterparty_node_id, msg), *counterparty_node_id);
3233         }
3234
3235         fn handle_funding_signed(&self, counterparty_node_id: &PublicKey, msg: &msgs::FundingSigned) {
3236                 let _ = self.total_consistency_lock.read().unwrap();
3237                 let _ = handle_error!(self, self.internal_funding_signed(counterparty_node_id, msg), *counterparty_node_id);
3238         }
3239
3240         fn handle_funding_locked(&self, counterparty_node_id: &PublicKey, msg: &msgs::FundingLocked) {
3241                 let _ = self.total_consistency_lock.read().unwrap();
3242                 let _ = handle_error!(self, self.internal_funding_locked(counterparty_node_id, msg), *counterparty_node_id);
3243         }
3244
3245         fn handle_shutdown(&self, counterparty_node_id: &PublicKey, msg: &msgs::Shutdown) {
3246                 let _ = self.total_consistency_lock.read().unwrap();
3247                 let _ = handle_error!(self, self.internal_shutdown(counterparty_node_id, msg), *counterparty_node_id);
3248         }
3249
3250         fn handle_closing_signed(&self, counterparty_node_id: &PublicKey, msg: &msgs::ClosingSigned) {
3251                 let _ = self.total_consistency_lock.read().unwrap();
3252                 let _ = handle_error!(self, self.internal_closing_signed(counterparty_node_id, msg), *counterparty_node_id);
3253         }
3254
3255         fn handle_update_add_htlc(&self, counterparty_node_id: &PublicKey, msg: &msgs::UpdateAddHTLC) {
3256                 let _ = self.total_consistency_lock.read().unwrap();
3257                 let _ = handle_error!(self, self.internal_update_add_htlc(counterparty_node_id, msg), *counterparty_node_id);
3258         }
3259
3260         fn handle_update_fulfill_htlc(&self, counterparty_node_id: &PublicKey, msg: &msgs::UpdateFulfillHTLC) {
3261                 let _ = self.total_consistency_lock.read().unwrap();
3262                 let _ = handle_error!(self, self.internal_update_fulfill_htlc(counterparty_node_id, msg), *counterparty_node_id);
3263         }
3264
3265         fn handle_update_fail_htlc(&self, counterparty_node_id: &PublicKey, msg: &msgs::UpdateFailHTLC) {
3266                 let _ = self.total_consistency_lock.read().unwrap();
3267                 let _ = handle_error!(self, self.internal_update_fail_htlc(counterparty_node_id, msg), *counterparty_node_id);
3268         }
3269
3270         fn handle_update_fail_malformed_htlc(&self, counterparty_node_id: &PublicKey, msg: &msgs::UpdateFailMalformedHTLC) {
3271                 let _ = self.total_consistency_lock.read().unwrap();
3272                 let _ = handle_error!(self, self.internal_update_fail_malformed_htlc(counterparty_node_id, msg), *counterparty_node_id);
3273         }
3274
3275         fn handle_commitment_signed(&self, counterparty_node_id: &PublicKey, msg: &msgs::CommitmentSigned) {
3276                 let _ = self.total_consistency_lock.read().unwrap();
3277                 let _ = handle_error!(self, self.internal_commitment_signed(counterparty_node_id, msg), *counterparty_node_id);
3278         }
3279
3280         fn handle_revoke_and_ack(&self, counterparty_node_id: &PublicKey, msg: &msgs::RevokeAndACK) {
3281                 let _ = self.total_consistency_lock.read().unwrap();
3282                 let _ = handle_error!(self, self.internal_revoke_and_ack(counterparty_node_id, msg), *counterparty_node_id);
3283         }
3284
3285         fn handle_update_fee(&self, counterparty_node_id: &PublicKey, msg: &msgs::UpdateFee) {
3286                 let _ = self.total_consistency_lock.read().unwrap();
3287                 let _ = handle_error!(self, self.internal_update_fee(counterparty_node_id, msg), *counterparty_node_id);
3288         }
3289
3290         fn handle_announcement_signatures(&self, counterparty_node_id: &PublicKey, msg: &msgs::AnnouncementSignatures) {
3291                 let _ = self.total_consistency_lock.read().unwrap();
3292                 let _ = handle_error!(self, self.internal_announcement_signatures(counterparty_node_id, msg), *counterparty_node_id);
3293         }
3294
3295         fn handle_channel_reestablish(&self, counterparty_node_id: &PublicKey, msg: &msgs::ChannelReestablish) {
3296                 let _ = self.total_consistency_lock.read().unwrap();
3297                 let _ = handle_error!(self, self.internal_channel_reestablish(counterparty_node_id, msg), *counterparty_node_id);
3298         }
3299
3300         fn peer_disconnected(&self, counterparty_node_id: &PublicKey, no_connection_possible: bool) {
3301                 let _ = self.total_consistency_lock.read().unwrap();
3302                 let mut failed_channels = Vec::new();
3303                 let mut failed_payments = Vec::new();
3304                 let mut no_channels_remain = true;
3305                 {
3306                         let mut channel_state_lock = self.channel_state.lock().unwrap();
3307                         let channel_state = &mut *channel_state_lock;
3308                         let short_to_id = &mut channel_state.short_to_id;
3309                         let pending_msg_events = &mut channel_state.pending_msg_events;
3310                         if no_connection_possible {
3311                                 log_debug!(self.logger, "Failing all channels with {} due to no_connection_possible", log_pubkey!(counterparty_node_id));
3312                                 channel_state.by_id.retain(|_, chan| {
3313                                         if chan.get_counterparty_node_id() == *counterparty_node_id {
3314                                                 if let Some(short_id) = chan.get_short_channel_id() {
3315                                                         short_to_id.remove(&short_id);
3316                                                 }
3317                                                 failed_channels.push(chan.force_shutdown(true));
3318                                                 if let Ok(update) = self.get_channel_update(&chan) {
3319                                                         pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
3320                                                                 msg: update
3321                                                         });
3322                                                 }
3323                                                 false
3324                                         } else {
3325                                                 true
3326                                         }
3327                                 });
3328                         } else {
3329                                 log_debug!(self.logger, "Marking channels with {} disconnected and generating channel_updates", log_pubkey!(counterparty_node_id));
3330                                 channel_state.by_id.retain(|_, chan| {
3331                                         if chan.get_counterparty_node_id() == *counterparty_node_id {
3332                                                 // Note that currently on channel reestablish we assert that there are no
3333                                                 // holding cell add-HTLCs, so if in the future we stop removing uncommitted HTLCs
3334                                                 // on peer disconnect here, there will need to be corresponding changes in
3335                                                 // reestablish logic.
3336                                                 let failed_adds = chan.remove_uncommitted_htlcs_and_mark_paused(&self.logger);
3337                                                 chan.to_disabled_marked();
3338                                                 if !failed_adds.is_empty() {
3339                                                         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
3340                                                         failed_payments.push((chan_update, failed_adds));
3341                                                 }
3342                                                 if chan.is_shutdown() {
3343                                                         if let Some(short_id) = chan.get_short_channel_id() {
3344                                                                 short_to_id.remove(&short_id);
3345                                                         }
3346                                                         return false;
3347                                                 } else {
3348                                                         no_channels_remain = false;
3349                                                 }
3350                                         }
3351                                         true
3352                                 })
3353                         }
3354                         pending_msg_events.retain(|msg| {
3355                                 match msg {
3356                                         &events::MessageSendEvent::SendAcceptChannel { ref node_id, .. } => node_id != counterparty_node_id,
3357                                         &events::MessageSendEvent::SendOpenChannel { ref node_id, .. } => node_id != counterparty_node_id,
3358                                         &events::MessageSendEvent::SendFundingCreated { ref node_id, .. } => node_id != counterparty_node_id,
3359                                         &events::MessageSendEvent::SendFundingSigned { ref node_id, .. } => node_id != counterparty_node_id,
3360                                         &events::MessageSendEvent::SendFundingLocked { ref node_id, .. } => node_id != counterparty_node_id,
3361                                         &events::MessageSendEvent::SendAnnouncementSignatures { ref node_id, .. } => node_id != counterparty_node_id,
3362                                         &events::MessageSendEvent::UpdateHTLCs { ref node_id, .. } => node_id != counterparty_node_id,
3363                                         &events::MessageSendEvent::SendRevokeAndACK { ref node_id, .. } => node_id != counterparty_node_id,
3364                                         &events::MessageSendEvent::SendClosingSigned { ref node_id, .. } => node_id != counterparty_node_id,
3365                                         &events::MessageSendEvent::SendShutdown { ref node_id, .. } => node_id != counterparty_node_id,
3366                                         &events::MessageSendEvent::SendChannelReestablish { ref node_id, .. } => node_id != counterparty_node_id,
3367                                         &events::MessageSendEvent::BroadcastChannelAnnouncement { .. } => true,
3368                                         &events::MessageSendEvent::BroadcastNodeAnnouncement { .. } => true,
3369                                         &events::MessageSendEvent::BroadcastChannelUpdate { .. } => true,
3370                                         &events::MessageSendEvent::HandleError { ref node_id, .. } => node_id != counterparty_node_id,
3371                                         &events::MessageSendEvent::PaymentFailureNetworkUpdate { .. } => true,
3372                                 }
3373                         });
3374                 }
3375                 if no_channels_remain {
3376                         self.per_peer_state.write().unwrap().remove(counterparty_node_id);
3377                 }
3378
3379                 for failure in failed_channels.drain(..) {
3380                         self.finish_force_close_channel(failure);
3381                 }
3382                 for (chan_update, mut htlc_sources) in failed_payments {
3383                         for (htlc_source, payment_hash) in htlc_sources.drain(..) {
3384                                 self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), htlc_source, &payment_hash, HTLCFailReason::Reason { failure_code: 0x1000 | 7, data: chan_update.clone() });
3385                         }
3386                 }
3387         }
3388
3389         fn peer_connected(&self, counterparty_node_id: &PublicKey, init_msg: &msgs::Init) {
3390                 log_debug!(self.logger, "Generating channel_reestablish events for {}", log_pubkey!(counterparty_node_id));
3391
3392                 let _ = self.total_consistency_lock.read().unwrap();
3393
3394                 {
3395                         let mut peer_state_lock = self.per_peer_state.write().unwrap();
3396                         match peer_state_lock.entry(counterparty_node_id.clone()) {
3397                                 hash_map::Entry::Vacant(e) => {
3398                                         e.insert(Mutex::new(PeerState {
3399                                                 latest_features: init_msg.features.clone(),
3400                                         }));
3401                                 },
3402                                 hash_map::Entry::Occupied(e) => {
3403                                         e.get().lock().unwrap().latest_features = init_msg.features.clone();
3404                                 },
3405                         }
3406                 }
3407
3408                 let mut channel_state_lock = self.channel_state.lock().unwrap();
3409                 let channel_state = &mut *channel_state_lock;
3410                 let pending_msg_events = &mut channel_state.pending_msg_events;
3411                 channel_state.by_id.retain(|_, chan| {
3412                         if chan.get_counterparty_node_id() == *counterparty_node_id {
3413                                 if !chan.have_received_message() {
3414                                         // If we created this (outbound) channel while we were disconnected from the
3415                                         // peer we probably failed to send the open_channel message, which is now
3416                                         // lost. We can't have had anything pending related to this channel, so we just
3417                                         // drop it.
3418                                         false
3419                                 } else {
3420                                         pending_msg_events.push(events::MessageSendEvent::SendChannelReestablish {
3421                                                 node_id: chan.get_counterparty_node_id(),
3422                                                 msg: chan.get_channel_reestablish(&self.logger),
3423                                         });
3424                                         true
3425                                 }
3426                         } else { true }
3427                 });
3428                 //TODO: Also re-broadcast announcement_signatures
3429         }
3430
3431         fn handle_error(&self, counterparty_node_id: &PublicKey, msg: &msgs::ErrorMessage) {
3432                 let _ = self.total_consistency_lock.read().unwrap();
3433
3434                 if msg.channel_id == [0; 32] {
3435                         for chan in self.list_channels() {
3436                                 if chan.remote_network_id == *counterparty_node_id {
3437                                         self.force_close_channel(&chan.channel_id);
3438                                 }
3439                         }
3440                 } else {
3441                         self.force_close_channel(&msg.channel_id);
3442                 }
3443         }
3444 }
3445
3446 const SERIALIZATION_VERSION: u8 = 1;
3447 const MIN_SERIALIZATION_VERSION: u8 = 1;
3448
3449 impl Writeable for PendingHTLCInfo {
3450         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3451                 match &self.routing {
3452                         &PendingHTLCRouting::Forward { ref onion_packet, ref short_channel_id } => {
3453                                 0u8.write(writer)?;
3454                                 onion_packet.write(writer)?;
3455                                 short_channel_id.write(writer)?;
3456                         },
3457                         &PendingHTLCRouting::Receive { ref payment_data, ref incoming_cltv_expiry } => {
3458                                 1u8.write(writer)?;
3459                                 payment_data.write(writer)?;
3460                                 incoming_cltv_expiry.write(writer)?;
3461                         },
3462                 }
3463                 self.incoming_shared_secret.write(writer)?;
3464                 self.payment_hash.write(writer)?;
3465                 self.amt_to_forward.write(writer)?;
3466                 self.outgoing_cltv_value.write(writer)?;
3467                 Ok(())
3468         }
3469 }
3470
3471 impl Readable for PendingHTLCInfo {
3472         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<PendingHTLCInfo, DecodeError> {
3473                 Ok(PendingHTLCInfo {
3474                         routing: match Readable::read(reader)? {
3475                                 0u8 => PendingHTLCRouting::Forward {
3476                                         onion_packet: Readable::read(reader)?,
3477                                         short_channel_id: Readable::read(reader)?,
3478                                 },
3479                                 1u8 => PendingHTLCRouting::Receive {
3480                                         payment_data: Readable::read(reader)?,
3481                                         incoming_cltv_expiry: Readable::read(reader)?,
3482                                 },
3483                                 _ => return Err(DecodeError::InvalidValue),
3484                         },
3485                         incoming_shared_secret: Readable::read(reader)?,
3486                         payment_hash: Readable::read(reader)?,
3487                         amt_to_forward: Readable::read(reader)?,
3488                         outgoing_cltv_value: Readable::read(reader)?,
3489                 })
3490         }
3491 }
3492
3493 impl Writeable for HTLCFailureMsg {
3494         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3495                 match self {
3496                         &HTLCFailureMsg::Relay(ref fail_msg) => {
3497                                 0u8.write(writer)?;
3498                                 fail_msg.write(writer)?;
3499                         },
3500                         &HTLCFailureMsg::Malformed(ref fail_msg) => {
3501                                 1u8.write(writer)?;
3502                                 fail_msg.write(writer)?;
3503                         }
3504                 }
3505                 Ok(())
3506         }
3507 }
3508
3509 impl Readable for HTLCFailureMsg {
3510         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<HTLCFailureMsg, DecodeError> {
3511                 match <u8 as Readable>::read(reader)? {
3512                         0 => Ok(HTLCFailureMsg::Relay(Readable::read(reader)?)),
3513                         1 => Ok(HTLCFailureMsg::Malformed(Readable::read(reader)?)),
3514                         _ => Err(DecodeError::InvalidValue),
3515                 }
3516         }
3517 }
3518
3519 impl Writeable for PendingHTLCStatus {
3520         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3521                 match self {
3522                         &PendingHTLCStatus::Forward(ref forward_info) => {
3523                                 0u8.write(writer)?;
3524                                 forward_info.write(writer)?;
3525                         },
3526                         &PendingHTLCStatus::Fail(ref fail_msg) => {
3527                                 1u8.write(writer)?;
3528                                 fail_msg.write(writer)?;
3529                         }
3530                 }
3531                 Ok(())
3532         }
3533 }
3534
3535 impl Readable for PendingHTLCStatus {
3536         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<PendingHTLCStatus, DecodeError> {
3537                 match <u8 as Readable>::read(reader)? {
3538                         0 => Ok(PendingHTLCStatus::Forward(Readable::read(reader)?)),
3539                         1 => Ok(PendingHTLCStatus::Fail(Readable::read(reader)?)),
3540                         _ => Err(DecodeError::InvalidValue),
3541                 }
3542         }
3543 }
3544
3545 impl_writeable!(HTLCPreviousHopData, 0, {
3546         short_channel_id,
3547         htlc_id,
3548         incoming_packet_shared_secret
3549 });
3550
3551 impl_writeable!(ClaimableHTLC, 0, {
3552         prev_hop,
3553         value,
3554         payment_data,
3555         cltv_expiry
3556 });
3557
3558 impl Writeable for HTLCSource {
3559         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3560                 match self {
3561                         &HTLCSource::PreviousHopData(ref hop_data) => {
3562                                 0u8.write(writer)?;
3563                                 hop_data.write(writer)?;
3564                         },
3565                         &HTLCSource::OutboundRoute { ref path, ref session_priv, ref first_hop_htlc_msat } => {
3566                                 1u8.write(writer)?;
3567                                 path.write(writer)?;
3568                                 session_priv.write(writer)?;
3569                                 first_hop_htlc_msat.write(writer)?;
3570                         }
3571                 }
3572                 Ok(())
3573         }
3574 }
3575
3576 impl Readable for HTLCSource {
3577         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<HTLCSource, DecodeError> {
3578                 match <u8 as Readable>::read(reader)? {
3579                         0 => Ok(HTLCSource::PreviousHopData(Readable::read(reader)?)),
3580                         1 => Ok(HTLCSource::OutboundRoute {
3581                                 path: Readable::read(reader)?,
3582                                 session_priv: Readable::read(reader)?,
3583                                 first_hop_htlc_msat: Readable::read(reader)?,
3584                         }),
3585                         _ => Err(DecodeError::InvalidValue),
3586                 }
3587         }
3588 }
3589
3590 impl Writeable for HTLCFailReason {
3591         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3592                 match self {
3593                         &HTLCFailReason::LightningError { ref err } => {
3594                                 0u8.write(writer)?;
3595                                 err.write(writer)?;
3596                         },
3597                         &HTLCFailReason::Reason { ref failure_code, ref data } => {
3598                                 1u8.write(writer)?;
3599                                 failure_code.write(writer)?;
3600                                 data.write(writer)?;
3601                         }
3602                 }
3603                 Ok(())
3604         }
3605 }
3606
3607 impl Readable for HTLCFailReason {
3608         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<HTLCFailReason, DecodeError> {
3609                 match <u8 as Readable>::read(reader)? {
3610                         0 => Ok(HTLCFailReason::LightningError { err: Readable::read(reader)? }),
3611                         1 => Ok(HTLCFailReason::Reason {
3612                                 failure_code: Readable::read(reader)?,
3613                                 data: Readable::read(reader)?,
3614                         }),
3615                         _ => Err(DecodeError::InvalidValue),
3616                 }
3617         }
3618 }
3619
3620 impl Writeable for HTLCForwardInfo {
3621         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3622                 match self {
3623                         &HTLCForwardInfo::AddHTLC { ref prev_short_channel_id, ref prev_htlc_id, ref forward_info } => {
3624                                 0u8.write(writer)?;
3625                                 prev_short_channel_id.write(writer)?;
3626                                 prev_htlc_id.write(writer)?;
3627                                 forward_info.write(writer)?;
3628                         },
3629                         &HTLCForwardInfo::FailHTLC { ref htlc_id, ref err_packet } => {
3630                                 1u8.write(writer)?;
3631                                 htlc_id.write(writer)?;
3632                                 err_packet.write(writer)?;
3633                         },
3634                 }
3635                 Ok(())
3636         }
3637 }
3638
3639 impl Readable for HTLCForwardInfo {
3640         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<HTLCForwardInfo, DecodeError> {
3641                 match <u8 as Readable>::read(reader)? {
3642                         0 => Ok(HTLCForwardInfo::AddHTLC {
3643                                 prev_short_channel_id: Readable::read(reader)?,
3644                                 prev_htlc_id: Readable::read(reader)?,
3645                                 forward_info: Readable::read(reader)?,
3646                         }),
3647                         1 => Ok(HTLCForwardInfo::FailHTLC {
3648                                 htlc_id: Readable::read(reader)?,
3649                                 err_packet: Readable::read(reader)?,
3650                         }),
3651                         _ => Err(DecodeError::InvalidValue),
3652                 }
3653         }
3654 }
3655
3656 impl<ChanSigner: ChannelKeys + Writeable, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> Writeable for ChannelManager<ChanSigner, M, T, K, F, L>
3657         where M::Target: chain::Watch<Keys=ChanSigner>,
3658         T::Target: BroadcasterInterface,
3659         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
3660         F::Target: FeeEstimator,
3661         L::Target: Logger,
3662 {
3663         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3664                 let _ = self.total_consistency_lock.write().unwrap();
3665
3666                 writer.write_all(&[SERIALIZATION_VERSION; 1])?;
3667                 writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
3668
3669                 self.genesis_hash.write(writer)?;
3670                 (self.latest_block_height.load(Ordering::Acquire) as u32).write(writer)?;
3671                 self.last_block_hash.lock().unwrap().write(writer)?;
3672
3673                 let channel_state = self.channel_state.lock().unwrap();
3674                 let mut unfunded_channels = 0;
3675                 for (_, channel) in channel_state.by_id.iter() {
3676                         if !channel.is_funding_initiated() {
3677                                 unfunded_channels += 1;
3678                         }
3679                 }
3680                 ((channel_state.by_id.len() - unfunded_channels) as u64).write(writer)?;
3681                 for (_, channel) in channel_state.by_id.iter() {
3682                         if channel.is_funding_initiated() {
3683                                 channel.write(writer)?;
3684                         }
3685                 }
3686
3687                 (channel_state.forward_htlcs.len() as u64).write(writer)?;
3688                 for (short_channel_id, pending_forwards) in channel_state.forward_htlcs.iter() {
3689                         short_channel_id.write(writer)?;
3690                         (pending_forwards.len() as u64).write(writer)?;
3691                         for forward in pending_forwards {
3692                                 forward.write(writer)?;
3693                         }
3694                 }
3695
3696                 (channel_state.claimable_htlcs.len() as u64).write(writer)?;
3697                 for (payment_hash, previous_hops) in channel_state.claimable_htlcs.iter() {
3698                         payment_hash.write(writer)?;
3699                         (previous_hops.len() as u64).write(writer)?;
3700                         for htlc in previous_hops.iter() {
3701                                 htlc.write(writer)?;
3702                         }
3703                 }
3704
3705                 let per_peer_state = self.per_peer_state.write().unwrap();
3706                 (per_peer_state.len() as u64).write(writer)?;
3707                 for (peer_pubkey, peer_state_mutex) in per_peer_state.iter() {
3708                         peer_pubkey.write(writer)?;
3709                         let peer_state = peer_state_mutex.lock().unwrap();
3710                         peer_state.latest_features.write(writer)?;
3711                 }
3712
3713                 let events = self.pending_events.lock().unwrap();
3714                 (events.len() as u64).write(writer)?;
3715                 for event in events.iter() {
3716                         event.write(writer)?;
3717                 }
3718
3719                 (self.last_node_announcement_serial.load(Ordering::Acquire) as u32).write(writer)?;
3720
3721                 Ok(())
3722         }
3723 }
3724
3725 /// Arguments for the creation of a ChannelManager that are not deserialized.
3726 ///
3727 /// At a high-level, the process for deserializing a ChannelManager and resuming normal operation
3728 /// is:
3729 /// 1) Deserialize all stored ChannelMonitors.
3730 /// 2) Deserialize the ChannelManager by filling in this struct and calling <(Sha256dHash,
3731 ///    ChannelManager)>::read(reader, args).
3732 ///    This may result in closing some Channels if the ChannelMonitor is newer than the stored
3733 ///    ChannelManager state to ensure no loss of funds. Thus, transactions may be broadcasted.
3734 /// 3) Register all relevant ChannelMonitor outpoints with your chain watch mechanism using
3735 ///    ChannelMonitor::get_monitored_outpoints and ChannelMonitor::get_funding_txo().
3736 /// 4) Reconnect blocks on your ChannelMonitors.
3737 /// 5) Move the ChannelMonitors into your local chain::Watch.
3738 /// 6) Disconnect/connect blocks on the ChannelManager.
3739 pub struct ChannelManagerReadArgs<'a, ChanSigner: 'a + ChannelKeys, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
3740         where M::Target: chain::Watch<Keys=ChanSigner>,
3741         T::Target: BroadcasterInterface,
3742         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
3743         F::Target: FeeEstimator,
3744         L::Target: Logger,
3745 {
3746         /// The keys provider which will give us relevant keys. Some keys will be loaded during
3747         /// deserialization.
3748         pub keys_manager: K,
3749
3750         /// The fee_estimator for use in the ChannelManager in the future.
3751         ///
3752         /// No calls to the FeeEstimator will be made during deserialization.
3753         pub fee_estimator: F,
3754         /// The chain::Watch for use in the ChannelManager in the future.
3755         ///
3756         /// No calls to the chain::Watch will be made during deserialization. It is assumed that
3757         /// you have deserialized ChannelMonitors separately and will add them to your
3758         /// chain::Watch after deserializing this ChannelManager.
3759         pub chain_monitor: M,
3760
3761         /// The BroadcasterInterface which will be used in the ChannelManager in the future and may be
3762         /// used to broadcast the latest local commitment transactions of channels which must be
3763         /// force-closed during deserialization.
3764         pub tx_broadcaster: T,
3765         /// The Logger for use in the ChannelManager and which may be used to log information during
3766         /// deserialization.
3767         pub logger: L,
3768         /// Default settings used for new channels. Any existing channels will continue to use the
3769         /// runtime settings which were stored when the ChannelManager was serialized.
3770         pub default_config: UserConfig,
3771
3772         /// A map from channel funding outpoints to ChannelMonitors for those channels (ie
3773         /// value.get_funding_txo() should be the key).
3774         ///
3775         /// If a monitor is inconsistent with the channel state during deserialization the channel will
3776         /// be force-closed using the data in the ChannelMonitor and the channel will be dropped. This
3777         /// is true for missing channels as well. If there is a monitor missing for which we find
3778         /// channel data Err(DecodeError::InvalidValue) will be returned.
3779         ///
3780         /// In such cases the latest local transactions will be sent to the tx_broadcaster included in
3781         /// this struct.
3782         ///
3783         /// (C-not exported) because we have no HashMap bindings
3784         pub channel_monitors: HashMap<OutPoint, &'a mut ChannelMonitor<ChanSigner>>,
3785 }
3786
3787 impl<'a, ChanSigner: 'a + ChannelKeys, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
3788                 ChannelManagerReadArgs<'a, ChanSigner, M, T, K, F, L>
3789         where M::Target: chain::Watch<Keys=ChanSigner>,
3790                 T::Target: BroadcasterInterface,
3791                 K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
3792                 F::Target: FeeEstimator,
3793                 L::Target: Logger,
3794         {
3795         /// Simple utility function to create a ChannelManagerReadArgs which creates the monitor
3796         /// HashMap for you. This is primarily useful for C bindings where it is not practical to
3797         /// populate a HashMap directly from C.
3798         pub fn new(keys_manager: K, fee_estimator: F, chain_monitor: M, tx_broadcaster: T, logger: L, default_config: UserConfig,
3799                         mut channel_monitors: Vec<&'a mut ChannelMonitor<ChanSigner>>) -> Self {
3800                 Self {
3801                         keys_manager, fee_estimator, chain_monitor, tx_broadcaster, logger, default_config,
3802                         channel_monitors: channel_monitors.drain(..).map(|monitor| { (monitor.get_funding_txo().0, monitor) }).collect()
3803                 }
3804         }
3805 }
3806
3807 // Implement ReadableArgs for an Arc'd ChannelManager to make it a bit easier to work with the
3808 // SipmleArcChannelManager type:
3809 impl<'a, ChanSigner: ChannelKeys + Readable, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
3810         ReadableArgs<ChannelManagerReadArgs<'a, ChanSigner, M, T, K, F, L>> for (BlockHash, Arc<ChannelManager<ChanSigner, M, T, K, F, L>>)
3811         where M::Target: chain::Watch<Keys=ChanSigner>,
3812         T::Target: BroadcasterInterface,
3813         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
3814         F::Target: FeeEstimator,
3815         L::Target: Logger,
3816 {
3817         fn read<R: ::std::io::Read>(reader: &mut R, args: ChannelManagerReadArgs<'a, ChanSigner, M, T, K, F, L>) -> Result<Self, DecodeError> {
3818                 let (blockhash, chan_manager) = <(BlockHash, ChannelManager<ChanSigner, M, T, K, F, L>)>::read(reader, args)?;
3819                 Ok((blockhash, Arc::new(chan_manager)))
3820         }
3821 }
3822
3823 impl<'a, ChanSigner: ChannelKeys + Readable, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
3824         ReadableArgs<ChannelManagerReadArgs<'a, ChanSigner, M, T, K, F, L>> for (BlockHash, ChannelManager<ChanSigner, M, T, K, F, L>)
3825         where M::Target: chain::Watch<Keys=ChanSigner>,
3826         T::Target: BroadcasterInterface,
3827         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
3828         F::Target: FeeEstimator,
3829         L::Target: Logger,
3830 {
3831         fn read<R: ::std::io::Read>(reader: &mut R, mut args: ChannelManagerReadArgs<'a, ChanSigner, M, T, K, F, L>) -> Result<Self, DecodeError> {
3832                 let _ver: u8 = Readable::read(reader)?;
3833                 let min_ver: u8 = Readable::read(reader)?;
3834                 if min_ver > SERIALIZATION_VERSION {
3835                         return Err(DecodeError::UnknownVersion);
3836                 }
3837
3838                 let genesis_hash: BlockHash = Readable::read(reader)?;
3839                 let latest_block_height: u32 = Readable::read(reader)?;
3840                 let last_block_hash: BlockHash = Readable::read(reader)?;
3841
3842                 let mut failed_htlcs = Vec::new();
3843
3844                 let channel_count: u64 = Readable::read(reader)?;
3845                 let mut funding_txo_set = HashSet::with_capacity(cmp::min(channel_count as usize, 128));
3846                 let mut by_id = HashMap::with_capacity(cmp::min(channel_count as usize, 128));
3847                 let mut short_to_id = HashMap::with_capacity(cmp::min(channel_count as usize, 128));
3848                 for _ in 0..channel_count {
3849                         let mut channel: Channel<ChanSigner> = Readable::read(reader)?;
3850                         if channel.last_block_connected != Default::default() && channel.last_block_connected != last_block_hash {
3851                                 return Err(DecodeError::InvalidValue);
3852                         }
3853
3854                         let funding_txo = channel.get_funding_txo().ok_or(DecodeError::InvalidValue)?;
3855                         funding_txo_set.insert(funding_txo.clone());
3856                         if let Some(ref mut monitor) = args.channel_monitors.get_mut(&funding_txo) {
3857                                 if channel.get_cur_holder_commitment_transaction_number() < monitor.get_cur_holder_commitment_number() ||
3858                                                 channel.get_revoked_counterparty_commitment_transaction_number() < monitor.get_min_seen_secret() ||
3859                                                 channel.get_cur_counterparty_commitment_transaction_number() < monitor.get_cur_counterparty_commitment_number() ||
3860                                                 channel.get_latest_monitor_update_id() > monitor.get_latest_update_id() {
3861                                         // If the channel is ahead of the monitor, return InvalidValue:
3862                                         return Err(DecodeError::InvalidValue);
3863                                 } else if channel.get_cur_holder_commitment_transaction_number() > monitor.get_cur_holder_commitment_number() ||
3864                                                 channel.get_revoked_counterparty_commitment_transaction_number() > monitor.get_min_seen_secret() ||
3865                                                 channel.get_cur_counterparty_commitment_transaction_number() > monitor.get_cur_counterparty_commitment_number() ||
3866                                                 channel.get_latest_monitor_update_id() < monitor.get_latest_update_id() {
3867                                         // But if the channel is behind of the monitor, close the channel:
3868                                         let (_, _, mut new_failed_htlcs) = channel.force_shutdown(true);
3869                                         failed_htlcs.append(&mut new_failed_htlcs);
3870                                         monitor.broadcast_latest_holder_commitment_txn(&args.tx_broadcaster, &args.logger);
3871                                 } else {
3872                                         if let Some(short_channel_id) = channel.get_short_channel_id() {
3873                                                 short_to_id.insert(short_channel_id, channel.channel_id());
3874                                         }
3875                                         by_id.insert(channel.channel_id(), channel);
3876                                 }
3877                         } else {
3878                                 return Err(DecodeError::InvalidValue);
3879                         }
3880                 }
3881
3882                 for (ref funding_txo, ref mut monitor) in args.channel_monitors.iter_mut() {
3883                         if !funding_txo_set.contains(funding_txo) {
3884                                 monitor.broadcast_latest_holder_commitment_txn(&args.tx_broadcaster, &args.logger);
3885                         }
3886                 }
3887
3888                 const MAX_ALLOC_SIZE: usize = 1024 * 64;
3889                 let forward_htlcs_count: u64 = Readable::read(reader)?;
3890                 let mut forward_htlcs = HashMap::with_capacity(cmp::min(forward_htlcs_count as usize, 128));
3891                 for _ in 0..forward_htlcs_count {
3892                         let short_channel_id = Readable::read(reader)?;
3893                         let pending_forwards_count: u64 = Readable::read(reader)?;
3894                         let mut pending_forwards = Vec::with_capacity(cmp::min(pending_forwards_count as usize, MAX_ALLOC_SIZE/mem::size_of::<HTLCForwardInfo>()));
3895                         for _ in 0..pending_forwards_count {
3896                                 pending_forwards.push(Readable::read(reader)?);
3897                         }
3898                         forward_htlcs.insert(short_channel_id, pending_forwards);
3899                 }
3900
3901                 let claimable_htlcs_count: u64 = Readable::read(reader)?;
3902                 let mut claimable_htlcs = HashMap::with_capacity(cmp::min(claimable_htlcs_count as usize, 128));
3903                 for _ in 0..claimable_htlcs_count {
3904                         let payment_hash = Readable::read(reader)?;
3905                         let previous_hops_len: u64 = Readable::read(reader)?;
3906                         let mut previous_hops = Vec::with_capacity(cmp::min(previous_hops_len as usize, MAX_ALLOC_SIZE/mem::size_of::<ClaimableHTLC>()));
3907                         for _ in 0..previous_hops_len {
3908                                 previous_hops.push(Readable::read(reader)?);
3909                         }
3910                         claimable_htlcs.insert(payment_hash, previous_hops);
3911                 }
3912
3913                 let peer_count: u64 = Readable::read(reader)?;
3914                 let mut per_peer_state = HashMap::with_capacity(cmp::min(peer_count as usize, MAX_ALLOC_SIZE/mem::size_of::<(PublicKey, Mutex<PeerState>)>()));
3915                 for _ in 0..peer_count {
3916                         let peer_pubkey = Readable::read(reader)?;
3917                         let peer_state = PeerState {
3918                                 latest_features: Readable::read(reader)?,
3919                         };
3920                         per_peer_state.insert(peer_pubkey, Mutex::new(peer_state));
3921                 }
3922
3923                 let event_count: u64 = Readable::read(reader)?;
3924                 let mut pending_events_read: Vec<events::Event> = Vec::with_capacity(cmp::min(event_count as usize, MAX_ALLOC_SIZE/mem::size_of::<events::Event>()));
3925                 for _ in 0..event_count {
3926                         match MaybeReadable::read(reader)? {
3927                                 Some(event) => pending_events_read.push(event),
3928                                 None => continue,
3929                         }
3930                 }
3931
3932                 let last_node_announcement_serial: u32 = Readable::read(reader)?;
3933
3934                 let channel_manager = ChannelManager {
3935                         genesis_hash,
3936                         fee_estimator: args.fee_estimator,
3937                         chain_monitor: args.chain_monitor,
3938                         tx_broadcaster: args.tx_broadcaster,
3939
3940                         latest_block_height: AtomicUsize::new(latest_block_height as usize),
3941                         last_block_hash: Mutex::new(last_block_hash),
3942                         secp_ctx: Secp256k1::new(),
3943
3944                         channel_state: Mutex::new(ChannelHolder {
3945                                 by_id,
3946                                 short_to_id,
3947                                 forward_htlcs,
3948                                 claimable_htlcs,
3949                                 pending_msg_events: Vec::new(),
3950                         }),
3951                         our_network_key: args.keys_manager.get_node_secret(),
3952
3953                         last_node_announcement_serial: AtomicUsize::new(last_node_announcement_serial as usize),
3954
3955                         per_peer_state: RwLock::new(per_peer_state),
3956
3957                         pending_events: Mutex::new(pending_events_read),
3958                         total_consistency_lock: RwLock::new(()),
3959                         keys_manager: args.keys_manager,
3960                         logger: args.logger,
3961                         default_configuration: args.default_config,
3962                 };
3963
3964                 for htlc_source in failed_htlcs.drain(..) {
3965                         channel_manager.fail_htlc_backwards_internal(channel_manager.channel_state.lock().unwrap(), htlc_source.0, &htlc_source.1, HTLCFailReason::Reason { failure_code: 0x4000 | 8, data: Vec::new() });
3966                 }
3967
3968                 //TODO: Broadcast channel update for closed channels, but only after we've made a
3969                 //connection or two.
3970
3971                 Ok((last_block_hash.clone(), channel_manager))
3972         }
3973 }