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[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
21 use bitcoin::blockdata::block::{Block, BlockHeader};
22 use bitcoin::blockdata::transaction::Transaction;
23 use bitcoin::blockdata::constants::genesis_block;
24 use bitcoin::network::constants::Network;
25
26 use bitcoin::hashes::{Hash, HashEngine};
27 use bitcoin::hashes::hmac::{Hmac, HmacEngine};
28 use bitcoin::hashes::sha256::Hash as Sha256;
29 use bitcoin::hashes::sha256d::Hash as Sha256dHash;
30 use bitcoin::hashes::cmp::fixed_time_eq;
31 use bitcoin::hash_types::{BlockHash, Txid};
32
33 use bitcoin::secp256k1::key::{SecretKey,PublicKey};
34 use bitcoin::secp256k1::Secp256k1;
35 use bitcoin::secp256k1::ecdh::SharedSecret;
36 use bitcoin::secp256k1;
37
38 use chain;
39 use chain::Confirm;
40 use chain::Watch;
41 use chain::chaininterface::{BroadcasterInterface, FeeEstimator};
42 use chain::channelmonitor::{ChannelMonitor, ChannelMonitorUpdate, ChannelMonitorUpdateStep, ChannelMonitorUpdateErr, HTLC_FAIL_BACK_BUFFER, CLTV_CLAIM_BUFFER, LATENCY_GRACE_PERIOD_BLOCKS, ANTI_REORG_DELAY, MonitorEvent, CLOSED_CHANNEL_UPDATE_ID};
43 use chain::transaction::{OutPoint, TransactionData};
44 // Since this struct is returned in `list_channels` methods, expose it here in case users want to
45 // construct one themselves.
46 pub use ln::channel::CounterpartyForwardingInfo;
47 use ln::channel::{Channel, ChannelError};
48 use ln::features::{InitFeatures, NodeFeatures};
49 use routing::router::{Route, RouteHop};
50 use ln::msgs;
51 use ln::msgs::NetAddress;
52 use ln::onion_utils;
53 use ln::msgs::{ChannelMessageHandler, DecodeError, LightningError, OptionalField};
54 use chain::keysinterface::{Sign, KeysInterface, KeysManager, InMemorySigner};
55 use util::config::UserConfig;
56 use util::events::{Event, EventsProvider, MessageSendEvent, MessageSendEventsProvider};
57 use util::{byte_utils, events};
58 use util::ser::{Readable, ReadableArgs, MaybeReadable, Writeable, Writer};
59 use util::chacha20::{ChaCha20, ChaChaReader};
60 use util::logger::Logger;
61 use util::errors::APIError;
62
63 use std::{cmp, mem};
64 use std::collections::{HashMap, hash_map, HashSet};
65 use std::io::{Cursor, Read};
66 use std::sync::{Arc, Condvar, Mutex, MutexGuard, RwLock, RwLockReadGuard};
67 use std::sync::atomic::{AtomicUsize, Ordering};
68 use std::time::Duration;
69 #[cfg(any(test, feature = "allow_wallclock_use"))]
70 use std::time::Instant;
71 use std::marker::{Sync, Send};
72 use std::ops::Deref;
73 use bitcoin::hashes::hex::ToHex;
74
75 // We hold various information about HTLC relay in the HTLC objects in Channel itself:
76 //
77 // Upon receipt of an HTLC from a peer, we'll give it a PendingHTLCStatus indicating if it should
78 // forward the HTLC with information it will give back to us when it does so, or if it should Fail
79 // the HTLC with the relevant message for the Channel to handle giving to the remote peer.
80 //
81 // Once said HTLC is committed in the Channel, if the PendingHTLCStatus indicated Forward, the
82 // Channel will return the PendingHTLCInfo back to us, and we will create an HTLCForwardInfo
83 // with it to track where it came from (in case of onwards-forward error), waiting a random delay
84 // before we forward it.
85 //
86 // We will then use HTLCForwardInfo's PendingHTLCInfo to construct an outbound HTLC, with a
87 // relevant HTLCSource::PreviousHopData filled in to indicate where it came from (which we can use
88 // to either fail-backwards or fulfill the HTLC backwards along the relevant path).
89 // Alternatively, we can fill an outbound HTLC with a HTLCSource::OutboundRoute indicating this is
90 // our payment, which we can use to decode errors or inform the user that the payment was sent.
91
92 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
93 enum PendingHTLCRouting {
94         Forward {
95                 onion_packet: msgs::OnionPacket,
96                 short_channel_id: u64, // This should be NonZero<u64> eventually when we bump MSRV
97         },
98         Receive {
99                 payment_data: msgs::FinalOnionHopData,
100                 incoming_cltv_expiry: u32, // Used to track when we should expire pending HTLCs that go unclaimed
101         },
102 }
103
104 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
105 pub(super) struct PendingHTLCInfo {
106         routing: PendingHTLCRouting,
107         incoming_shared_secret: [u8; 32],
108         payment_hash: PaymentHash,
109         pub(super) amt_to_forward: u64,
110         pub(super) outgoing_cltv_value: u32,
111 }
112
113 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
114 pub(super) enum HTLCFailureMsg {
115         Relay(msgs::UpdateFailHTLC),
116         Malformed(msgs::UpdateFailMalformedHTLC),
117 }
118
119 /// Stores whether we can't forward an HTLC or relevant forwarding info
120 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
121 pub(super) enum PendingHTLCStatus {
122         Forward(PendingHTLCInfo),
123         Fail(HTLCFailureMsg),
124 }
125
126 pub(super) enum HTLCForwardInfo {
127         AddHTLC {
128                 forward_info: PendingHTLCInfo,
129
130                 // These fields are produced in `forward_htlcs()` and consumed in
131                 // `process_pending_htlc_forwards()` for constructing the
132                 // `HTLCSource::PreviousHopData` for failed and forwarded
133                 // HTLCs.
134                 prev_short_channel_id: u64,
135                 prev_htlc_id: u64,
136                 prev_funding_outpoint: OutPoint,
137         },
138         FailHTLC {
139                 htlc_id: u64,
140                 err_packet: msgs::OnionErrorPacket,
141         },
142 }
143
144 /// Tracks the inbound corresponding to an outbound HTLC
145 #[derive(Clone, PartialEq)]
146 pub(crate) struct HTLCPreviousHopData {
147         short_channel_id: u64,
148         htlc_id: u64,
149         incoming_packet_shared_secret: [u8; 32],
150
151         // This field is consumed by `claim_funds_from_hop()` when updating a force-closed backwards
152         // channel with a preimage provided by the forward channel.
153         outpoint: OutPoint,
154 }
155
156 struct ClaimableHTLC {
157         prev_hop: HTLCPreviousHopData,
158         value: u64,
159         /// Contains a total_msat (which may differ from value if this is a Multi-Path Payment) and a
160         /// payment_secret which prevents path-probing attacks and can associate different HTLCs which
161         /// are part of the same payment.
162         payment_data: msgs::FinalOnionHopData,
163         cltv_expiry: u32,
164 }
165
166 /// Tracks the inbound corresponding to an outbound HTLC
167 #[derive(Clone, PartialEq)]
168 pub(crate) enum HTLCSource {
169         PreviousHopData(HTLCPreviousHopData),
170         OutboundRoute {
171                 path: Vec<RouteHop>,
172                 session_priv: SecretKey,
173                 /// Technically we can recalculate this from the route, but we cache it here to avoid
174                 /// doing a double-pass on route when we get a failure back
175                 first_hop_htlc_msat: u64,
176         },
177 }
178 #[cfg(test)]
179 impl HTLCSource {
180         pub fn dummy() -> Self {
181                 HTLCSource::OutboundRoute {
182                         path: Vec::new(),
183                         session_priv: SecretKey::from_slice(&[1; 32]).unwrap(),
184                         first_hop_htlc_msat: 0,
185                 }
186         }
187 }
188
189 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
190 pub(super) enum HTLCFailReason {
191         LightningError {
192                 err: msgs::OnionErrorPacket,
193         },
194         Reason {
195                 failure_code: u16,
196                 data: Vec<u8>,
197         }
198 }
199
200 /// payment_hash type, use to cross-lock hop
201 /// (C-not exported) as we just use [u8; 32] directly
202 #[derive(Hash, Copy, Clone, PartialEq, Eq, Debug)]
203 pub struct PaymentHash(pub [u8;32]);
204 /// payment_preimage type, use to route payment between hop
205 /// (C-not exported) as we just use [u8; 32] directly
206 #[derive(Hash, Copy, Clone, PartialEq, Eq, Debug)]
207 pub struct PaymentPreimage(pub [u8;32]);
208 /// payment_secret type, use to authenticate sender to the receiver and tie MPP HTLCs together
209 /// (C-not exported) as we just use [u8; 32] directly
210 #[derive(Hash, Copy, Clone, PartialEq, Eq, Debug)]
211 pub struct PaymentSecret(pub [u8;32]);
212
213 type ShutdownResult = (Option<(OutPoint, ChannelMonitorUpdate)>, Vec<(HTLCSource, PaymentHash)>);
214
215 /// Error type returned across the channel_state mutex boundary. When an Err is generated for a
216 /// Channel, we generally end up with a ChannelError::Close for which we have to close the channel
217 /// immediately (ie with no further calls on it made). Thus, this step happens inside a
218 /// channel_state lock. We then return the set of things that need to be done outside the lock in
219 /// this struct and call handle_error!() on it.
220
221 struct MsgHandleErrInternal {
222         err: msgs::LightningError,
223         shutdown_finish: Option<(ShutdownResult, Option<msgs::ChannelUpdate>)>,
224 }
225 impl MsgHandleErrInternal {
226         #[inline]
227         fn send_err_msg_no_close(err: String, channel_id: [u8; 32]) -> Self {
228                 Self {
229                         err: LightningError {
230                                 err: err.clone(),
231                                 action: msgs::ErrorAction::SendErrorMessage {
232                                         msg: msgs::ErrorMessage {
233                                                 channel_id,
234                                                 data: err
235                                         },
236                                 },
237                         },
238                         shutdown_finish: None,
239                 }
240         }
241         #[inline]
242         fn ignore_no_close(err: String) -> Self {
243                 Self {
244                         err: LightningError {
245                                 err,
246                                 action: msgs::ErrorAction::IgnoreError,
247                         },
248                         shutdown_finish: None,
249                 }
250         }
251         #[inline]
252         fn from_no_close(err: msgs::LightningError) -> Self {
253                 Self { err, shutdown_finish: None }
254         }
255         #[inline]
256         fn from_finish_shutdown(err: String, channel_id: [u8; 32], shutdown_res: ShutdownResult, channel_update: Option<msgs::ChannelUpdate>) -> Self {
257                 Self {
258                         err: LightningError {
259                                 err: err.clone(),
260                                 action: msgs::ErrorAction::SendErrorMessage {
261                                         msg: msgs::ErrorMessage {
262                                                 channel_id,
263                                                 data: err
264                                         },
265                                 },
266                         },
267                         shutdown_finish: Some((shutdown_res, channel_update)),
268                 }
269         }
270         #[inline]
271         fn from_chan_no_close(err: ChannelError, channel_id: [u8; 32]) -> Self {
272                 Self {
273                         err: match err {
274                                 ChannelError::Ignore(msg) => LightningError {
275                                         err: msg,
276                                         action: msgs::ErrorAction::IgnoreError,
277                                 },
278                                 ChannelError::Close(msg) => LightningError {
279                                         err: msg.clone(),
280                                         action: msgs::ErrorAction::SendErrorMessage {
281                                                 msg: msgs::ErrorMessage {
282                                                         channel_id,
283                                                         data: msg
284                                                 },
285                                         },
286                                 },
287                                 ChannelError::CloseDelayBroadcast(msg) => LightningError {
288                                         err: msg.clone(),
289                                         action: msgs::ErrorAction::SendErrorMessage {
290                                                 msg: msgs::ErrorMessage {
291                                                         channel_id,
292                                                         data: msg
293                                                 },
294                                         },
295                                 },
296                         },
297                         shutdown_finish: None,
298                 }
299         }
300 }
301
302 /// We hold back HTLCs we intend to relay for a random interval greater than this (see
303 /// Event::PendingHTLCsForwardable for the API guidelines indicating how long should be waited).
304 /// This provides some limited amount of privacy. Ideally this would range from somewhere like one
305 /// second to 30 seconds, but people expect lightning to be, you know, kinda fast, sadly.
306 const MIN_HTLC_RELAY_HOLDING_CELL_MILLIS: u64 = 100;
307
308 /// For events which result in both a RevokeAndACK and a CommitmentUpdate, by default they should
309 /// be sent in the order they appear in the return value, however sometimes the order needs to be
310 /// variable at runtime (eg Channel::channel_reestablish needs to re-send messages in the order
311 /// they were originally sent). In those cases, this enum is also returned.
312 #[derive(Clone, PartialEq)]
313 pub(super) enum RAACommitmentOrder {
314         /// Send the CommitmentUpdate messages first
315         CommitmentFirst,
316         /// Send the RevokeAndACK message first
317         RevokeAndACKFirst,
318 }
319
320 // Note this is only exposed in cfg(test):
321 pub(super) struct ChannelHolder<Signer: Sign> {
322         pub(super) by_id: HashMap<[u8; 32], Channel<Signer>>,
323         pub(super) short_to_id: HashMap<u64, [u8; 32]>,
324         /// short channel id -> forward infos. Key of 0 means payments received
325         /// Note that while this is held in the same mutex as the channels themselves, no consistency
326         /// guarantees are made about the existence of a channel with the short id here, nor the short
327         /// ids in the PendingHTLCInfo!
328         pub(super) forward_htlcs: HashMap<u64, Vec<HTLCForwardInfo>>,
329         /// Map from payment hash to any HTLCs which are to us and can be failed/claimed by the user.
330         /// Note that while this is held in the same mutex as the channels themselves, no consistency
331         /// guarantees are made about the channels given here actually existing anymore by the time you
332         /// go to read them!
333         claimable_htlcs: HashMap<PaymentHash, Vec<ClaimableHTLC>>,
334         /// Messages to send to peers - pushed to in the same lock that they are generated in (except
335         /// for broadcast messages, where ordering isn't as strict).
336         pub(super) pending_msg_events: Vec<MessageSendEvent>,
337 }
338
339 /// Events which we process internally but cannot be procsesed immediately at the generation site
340 /// for some reason. They are handled in timer_tick_occurred, so may be processed with
341 /// quite some time lag.
342 enum BackgroundEvent {
343         /// Handle a ChannelMonitorUpdate that closes a channel, broadcasting its current latest holder
344         /// commitment transaction.
345         ClosingMonitorUpdate((OutPoint, ChannelMonitorUpdate)),
346 }
347
348 /// State we hold per-peer. In the future we should put channels in here, but for now we only hold
349 /// the latest Init features we heard from the peer.
350 struct PeerState {
351         latest_features: InitFeatures,
352 }
353
354 /// Stores a PaymentSecret and any other data we may need to validate an inbound payment is
355 /// actually ours and not some duplicate HTLC sent to us by a node along the route.
356 ///
357 /// For users who don't want to bother doing their own payment preimage storage, we also store that
358 /// here.
359 struct PendingInboundPayment {
360         /// The payment secret that the sender must use for us to accept this payment
361         payment_secret: PaymentSecret,
362         /// Time at which this HTLC expires - blocks with a header time above this value will result in
363         /// this payment being removed.
364         expiry_time: u64,
365         /// Arbitrary identifier the user specifies (or not)
366         user_payment_id: u64,
367         // Other required attributes of the payment, optionally enforced:
368         payment_preimage: Option<PaymentPreimage>,
369         min_value_msat: Option<u64>,
370 }
371
372 /// SimpleArcChannelManager is useful when you need a ChannelManager with a static lifetime, e.g.
373 /// when you're using lightning-net-tokio (since tokio::spawn requires parameters with static
374 /// lifetimes). Other times you can afford a reference, which is more efficient, in which case
375 /// SimpleRefChannelManager is the more appropriate type. Defining these type aliases prevents
376 /// issues such as overly long function definitions. Note that the ChannelManager can take any
377 /// type that implements KeysInterface for its keys manager, but this type alias chooses the
378 /// concrete type of the KeysManager.
379 pub type SimpleArcChannelManager<M, T, F, L> = ChannelManager<InMemorySigner, Arc<M>, Arc<T>, Arc<KeysManager>, Arc<F>, Arc<L>>;
380
381 /// SimpleRefChannelManager is a type alias for a ChannelManager reference, and is the reference
382 /// counterpart to the SimpleArcChannelManager type alias. Use this type by default when you don't
383 /// need a ChannelManager with a static lifetime. You'll need a static lifetime in cases such as
384 /// usage of lightning-net-tokio (since tokio::spawn requires parameters with static lifetimes).
385 /// But if this is not necessary, using a reference is more efficient. Defining these type aliases
386 /// helps with issues such as long function definitions. Note that the ChannelManager can take any
387 /// type that implements KeysInterface for its keys manager, but this type alias chooses the
388 /// concrete type of the KeysManager.
389 pub type SimpleRefChannelManager<'a, 'b, 'c, 'd, 'e, M, T, F, L> = ChannelManager<InMemorySigner, &'a M, &'b T, &'c KeysManager, &'d F, &'e L>;
390
391 /// Manager which keeps track of a number of channels and sends messages to the appropriate
392 /// channel, also tracking HTLC preimages and forwarding onion packets appropriately.
393 ///
394 /// Implements ChannelMessageHandler, handling the multi-channel parts and passing things through
395 /// to individual Channels.
396 ///
397 /// Implements Writeable to write out all channel state to disk. Implies peer_disconnected() for
398 /// all peers during write/read (though does not modify this instance, only the instance being
399 /// serialized). This will result in any channels which have not yet exchanged funding_created (ie
400 /// called funding_transaction_generated for outbound channels).
401 ///
402 /// Note that you can be a bit lazier about writing out ChannelManager than you can be with
403 /// ChannelMonitors. With ChannelMonitors you MUST write each monitor update out to disk before
404 /// returning from chain::Watch::watch_/update_channel, with ChannelManagers, writing updates
405 /// happens out-of-band (and will prevent any other ChannelManager operations from occurring during
406 /// the serialization process). If the deserialized version is out-of-date compared to the
407 /// ChannelMonitors passed by reference to read(), those channels will be force-closed based on the
408 /// ChannelMonitor state and no funds will be lost (mod on-chain transaction fees).
409 ///
410 /// Note that the deserializer is only implemented for (BlockHash, ChannelManager), which
411 /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
412 /// the "reorg path" (ie call block_disconnected() until you get to a common block and then call
413 /// block_connected() to step towards your best block) upon deserialization before using the
414 /// object!
415 ///
416 /// Note that ChannelManager is responsible for tracking liveness of its channels and generating
417 /// ChannelUpdate messages informing peers that the channel is temporarily disabled. To avoid
418 /// spam due to quick disconnection/reconnection, updates are not sent until the channel has been
419 /// offline for a full minute. In order to track this, you must call
420 /// timer_tick_occurred roughly once per minute, though it doesn't have to be perfect.
421 ///
422 /// Rather than using a plain ChannelManager, it is preferable to use either a SimpleArcChannelManager
423 /// a SimpleRefChannelManager, for conciseness. See their documentation for more details, but
424 /// essentially you should default to using a SimpleRefChannelManager, and use a
425 /// SimpleArcChannelManager when you require a ChannelManager with a static lifetime, such as when
426 /// you're using lightning-net-tokio.
427 pub struct ChannelManager<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
428         where M::Target: chain::Watch<Signer>,
429         T::Target: BroadcasterInterface,
430         K::Target: KeysInterface<Signer = Signer>,
431         F::Target: FeeEstimator,
432                                 L::Target: Logger,
433 {
434         default_configuration: UserConfig,
435         genesis_hash: BlockHash,
436         fee_estimator: F,
437         chain_monitor: M,
438         tx_broadcaster: T,
439
440         #[cfg(test)]
441         pub(super) best_block: RwLock<BestBlock>,
442         #[cfg(not(test))]
443         best_block: RwLock<BestBlock>,
444         secp_ctx: Secp256k1<secp256k1::All>,
445
446         #[cfg(any(test, feature = "_test_utils"))]
447         pub(super) channel_state: Mutex<ChannelHolder<Signer>>,
448         #[cfg(not(any(test, feature = "_test_utils")))]
449         channel_state: Mutex<ChannelHolder<Signer>>,
450
451         /// Storage for PaymentSecrets and any requirements on future inbound payments before we will
452         /// expose them to users via a PaymentReceived event. HTLCs which do not meet the requirements
453         /// here are failed when we process them as pending-forwardable-HTLCs, and entries are removed
454         /// after we generate a PaymentReceived upon receipt of all MPP parts or when they time out.
455         /// Locked *after* channel_state.
456         pending_inbound_payments: Mutex<HashMap<PaymentHash, PendingInboundPayment>>,
457
458         our_network_key: SecretKey,
459         our_network_pubkey: PublicKey,
460
461         /// Used to track the last value sent in a node_announcement "timestamp" field. We ensure this
462         /// value increases strictly since we don't assume access to a time source.
463         last_node_announcement_serial: AtomicUsize,
464
465         /// The highest block timestamp we've seen, which is usually a good guess at the current time.
466         /// Assuming most miners are generating blocks with reasonable timestamps, this shouldn't be
467         /// very far in the past, and can only ever be up to two hours in the future.
468         highest_seen_timestamp: AtomicUsize,
469
470         /// The bulk of our storage will eventually be here (channels and message queues and the like).
471         /// If we are connected to a peer we always at least have an entry here, even if no channels
472         /// are currently open with that peer.
473         /// Because adding or removing an entry is rare, we usually take an outer read lock and then
474         /// operate on the inner value freely. Sadly, this prevents parallel operation when opening a
475         /// new channel.
476         per_peer_state: RwLock<HashMap<PublicKey, Mutex<PeerState>>>,
477
478         pending_events: Mutex<Vec<events::Event>>,
479         pending_background_events: Mutex<Vec<BackgroundEvent>>,
480         /// Used when we have to take a BIG lock to make sure everything is self-consistent.
481         /// Essentially just when we're serializing ourselves out.
482         /// Taken first everywhere where we are making changes before any other locks.
483         /// When acquiring this lock in read mode, rather than acquiring it directly, call
484         /// `PersistenceNotifierGuard::new(..)` and pass the lock to it, to ensure the PersistenceNotifier
485         /// the lock contains sends out a notification when the lock is released.
486         total_consistency_lock: RwLock<()>,
487
488         persistence_notifier: PersistenceNotifier,
489
490         keys_manager: K,
491
492         logger: L,
493 }
494
495 /// Chain-related parameters used to construct a new `ChannelManager`.
496 ///
497 /// Typically, the block-specific parameters are derived from the best block hash for the network,
498 /// as a newly constructed `ChannelManager` will not have created any channels yet. These parameters
499 /// are not needed when deserializing a previously constructed `ChannelManager`.
500 pub struct ChainParameters {
501         /// The network for determining the `chain_hash` in Lightning messages.
502         pub network: Network,
503
504         /// The hash and height of the latest block successfully connected.
505         ///
506         /// Used to track on-chain channel funding outputs and send payments with reliable timelocks.
507         pub best_block: BestBlock,
508 }
509
510 /// The best known block as identified by its hash and height.
511 #[derive(Clone, Copy)]
512 pub struct BestBlock {
513         block_hash: BlockHash,
514         height: u32,
515 }
516
517 impl BestBlock {
518         /// Returns the best block from the genesis of the given network.
519         pub fn from_genesis(network: Network) -> Self {
520                 BestBlock {
521                         block_hash: genesis_block(network).header.block_hash(),
522                         height: 0,
523                 }
524         }
525
526         /// Returns the best block as identified by the given block hash and height.
527         pub fn new(block_hash: BlockHash, height: u32) -> Self {
528                 BestBlock { block_hash, height }
529         }
530
531         /// Returns the best block hash.
532         pub fn block_hash(&self) -> BlockHash { self.block_hash }
533
534         /// Returns the best block height.
535         pub fn height(&self) -> u32 { self.height }
536 }
537
538 /// Whenever we release the `ChannelManager`'s `total_consistency_lock`, from read mode, it is
539 /// desirable to notify any listeners on `await_persistable_update_timeout`/
540 /// `await_persistable_update` that new updates are available for persistence. Therefore, this
541 /// struct is responsible for locking the total consistency lock and, upon going out of scope,
542 /// sending the aforementioned notification (since the lock being released indicates that the
543 /// updates are ready for persistence).
544 struct PersistenceNotifierGuard<'a> {
545         persistence_notifier: &'a PersistenceNotifier,
546         // We hold onto this result so the lock doesn't get released immediately.
547         _read_guard: RwLockReadGuard<'a, ()>,
548 }
549
550 impl<'a> PersistenceNotifierGuard<'a> {
551         fn new(lock: &'a RwLock<()>, notifier: &'a PersistenceNotifier) -> Self {
552                 let read_guard = lock.read().unwrap();
553
554                 Self {
555                         persistence_notifier: notifier,
556                         _read_guard: read_guard,
557                 }
558         }
559 }
560
561 impl<'a> Drop for PersistenceNotifierGuard<'a> {
562         fn drop(&mut self) {
563                 self.persistence_notifier.notify();
564         }
565 }
566
567 /// The amount of time in blocks we require our counterparty wait to claim their money (ie time
568 /// between when we, or our watchtower, must check for them having broadcast a theft transaction).
569 ///
570 /// This can be increased (but not decreased) through [`ChannelHandshakeConfig::our_to_self_delay`]
571 ///
572 /// [`ChannelHandshakeConfig::our_to_self_delay`]: crate::util::config::ChannelHandshakeConfig::our_to_self_delay
573 pub const BREAKDOWN_TIMEOUT: u16 = 6 * 24;
574 /// The amount of time in blocks we're willing to wait to claim money back to us. This matches
575 /// the maximum required amount in lnd as of March 2021.
576 pub(crate) const MAX_LOCAL_BREAKDOWN_TIMEOUT: u16 = 2 * 6 * 24 * 7;
577
578 /// The minimum number of blocks between an inbound HTLC's CLTV and the corresponding outbound
579 /// HTLC's CLTV. The current default represents roughly six hours of blocks at six blocks/hour.
580 ///
581 /// This can be increased (but not decreased) through [`ChannelConfig::cltv_expiry_delta`]
582 ///
583 /// [`ChannelConfig::cltv_expiry_delta`]: crate::util::config::ChannelConfig::cltv_expiry_delta
584 // This should always be a few blocks greater than channelmonitor::CLTV_CLAIM_BUFFER,
585 // i.e. the node we forwarded the payment on to should always have enough room to reliably time out
586 // the HTLC via a full update_fail_htlc/commitment_signed dance before we hit the
587 // CLTV_CLAIM_BUFFER point (we static assert that it's at least 3 blocks more).
588 pub const MIN_CLTV_EXPIRY_DELTA: u16 = 6 * 6;
589 pub(super) const CLTV_FAR_FAR_AWAY: u32 = 6 * 24 * 7; //TODO?
590
591 /// Minimum CLTV difference between the current block height and received inbound payments.
592 /// Invoices generated for payment to us must set their `min_final_cltv_expiry` field to at least
593 /// this value.
594 pub const MIN_FINAL_CLTV_EXPIRY: u32 = HTLC_FAIL_BACK_BUFFER;
595
596 // Check that our CLTV_EXPIRY is at least CLTV_CLAIM_BUFFER + ANTI_REORG_DELAY + LATENCY_GRACE_PERIOD_BLOCKS,
597 // ie that if the next-hop peer fails the HTLC within
598 // LATENCY_GRACE_PERIOD_BLOCKS then we'll still have CLTV_CLAIM_BUFFER left to timeout it onchain,
599 // then waiting ANTI_REORG_DELAY to be reorg-safe on the outbound HLTC and
600 // failing the corresponding htlc backward, and us now seeing the last block of ANTI_REORG_DELAY before
601 // LATENCY_GRACE_PERIOD_BLOCKS.
602 #[deny(const_err)]
603 #[allow(dead_code)]
604 const CHECK_CLTV_EXPIRY_SANITY: u32 = MIN_CLTV_EXPIRY_DELTA as u32 - LATENCY_GRACE_PERIOD_BLOCKS - CLTV_CLAIM_BUFFER - ANTI_REORG_DELAY - LATENCY_GRACE_PERIOD_BLOCKS;
605
606 // Check for ability of an attacker to make us fail on-chain by delaying inbound claim. See
607 // ChannelMontior::would_broadcast_at_height for a description of why this is needed.
608 #[deny(const_err)]
609 #[allow(dead_code)]
610 const CHECK_CLTV_EXPIRY_SANITY_2: u32 = MIN_CLTV_EXPIRY_DELTA as u32 - LATENCY_GRACE_PERIOD_BLOCKS - 2*CLTV_CLAIM_BUFFER;
611
612 /// Details of a channel, as returned by ChannelManager::list_channels and ChannelManager::list_usable_channels
613 #[derive(Clone)]
614 pub struct ChannelDetails {
615         /// The channel's ID (prior to funding transaction generation, this is a random 32 bytes,
616         /// thereafter this is the txid of the funding transaction xor the funding transaction output).
617         /// Note that this means this value is *not* persistent - it can change once during the
618         /// lifetime of the channel.
619         pub channel_id: [u8; 32],
620         /// The position of the funding transaction in the chain. None if the funding transaction has
621         /// not yet been confirmed and the channel fully opened.
622         pub short_channel_id: Option<u64>,
623         /// The node_id of our counterparty
624         pub remote_network_id: PublicKey,
625         /// The Features the channel counterparty provided upon last connection.
626         /// Useful for routing as it is the most up-to-date copy of the counterparty's features and
627         /// many routing-relevant features are present in the init context.
628         pub counterparty_features: InitFeatures,
629         /// The value, in satoshis, of this channel as appears in the funding output
630         pub channel_value_satoshis: u64,
631         /// The user_id passed in to create_channel, or 0 if the channel was inbound.
632         pub user_id: u64,
633         /// The available outbound capacity for sending HTLCs to the remote peer. This does not include
634         /// any pending HTLCs which are not yet fully resolved (and, thus, who's balance is not
635         /// available for inclusion in new outbound HTLCs). This further does not include any pending
636         /// outgoing HTLCs which are awaiting some other resolution to be sent.
637         pub outbound_capacity_msat: u64,
638         /// The available inbound capacity for the remote peer to send HTLCs to us. This does not
639         /// include any pending HTLCs which are not yet fully resolved (and, thus, who's balance is not
640         /// available for inclusion in new inbound HTLCs).
641         /// Note that there are some corner cases not fully handled here, so the actual available
642         /// inbound capacity may be slightly higher than this.
643         pub inbound_capacity_msat: u64,
644         /// True if the channel is (a) confirmed and funding_locked messages have been exchanged, (b)
645         /// the peer is connected, and (c) no monitor update failure is pending resolution.
646         pub is_live: bool,
647
648         /// Information on the fees and requirements that the counterparty requires when forwarding
649         /// payments to us through this channel.
650         pub counterparty_forwarding_info: Option<CounterpartyForwardingInfo>,
651 }
652
653 /// If a payment fails to send, it can be in one of several states. This enum is returned as the
654 /// Err() type describing which state the payment is in, see the description of individual enum
655 /// states for more.
656 #[derive(Clone, Debug)]
657 pub enum PaymentSendFailure {
658         /// A parameter which was passed to send_payment was invalid, preventing us from attempting to
659         /// send the payment at all. No channel state has been changed or messages sent to peers, and
660         /// once you've changed the parameter at error, you can freely retry the payment in full.
661         ParameterError(APIError),
662         /// A parameter in a single path which was passed to send_payment was invalid, preventing us
663         /// from attempting to send the payment at all. No channel state has been changed or messages
664         /// sent to peers, and once you've changed the parameter at error, you can freely retry the
665         /// payment in full.
666         ///
667         /// The results here are ordered the same as the paths in the route object which was passed to
668         /// send_payment.
669         PathParameterError(Vec<Result<(), APIError>>),
670         /// All paths which were attempted failed to send, with no channel state change taking place.
671         /// You can freely retry the payment in full (though you probably want to do so over different
672         /// paths than the ones selected).
673         AllFailedRetrySafe(Vec<APIError>),
674         /// Some paths which were attempted failed to send, though possibly not all. At least some
675         /// paths have irrevocably committed to the HTLC and retrying the payment in full would result
676         /// in over-/re-payment.
677         ///
678         /// The results here are ordered the same as the paths in the route object which was passed to
679         /// send_payment, and any Errs which are not APIError::MonitorUpdateFailed can be safely
680         /// retried (though there is currently no API with which to do so).
681         ///
682         /// Any entries which contain Err(APIError::MonitorUpdateFailed) or Ok(()) MUST NOT be retried
683         /// as they will result in over-/re-payment. These HTLCs all either successfully sent (in the
684         /// case of Ok(())) or will send once channel_monitor_updated is called on the next-hop channel
685         /// with the latest update_id.
686         PartialFailure(Vec<Result<(), APIError>>),
687 }
688
689 macro_rules! handle_error {
690         ($self: ident, $internal: expr, $counterparty_node_id: expr) => {
691                 match $internal {
692                         Ok(msg) => Ok(msg),
693                         Err(MsgHandleErrInternal { err, shutdown_finish }) => {
694                                 #[cfg(debug_assertions)]
695                                 {
696                                         // In testing, ensure there are no deadlocks where the lock is already held upon
697                                         // entering the macro.
698                                         assert!($self.channel_state.try_lock().is_ok());
699                                 }
700
701                                 let mut msg_events = Vec::with_capacity(2);
702
703                                 if let Some((shutdown_res, update_option)) = shutdown_finish {
704                                         $self.finish_force_close_channel(shutdown_res);
705                                         if let Some(update) = update_option {
706                                                 msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
707                                                         msg: update
708                                                 });
709                                         }
710                                 }
711
712                                 log_error!($self.logger, "{}", err.err);
713                                 if let msgs::ErrorAction::IgnoreError = err.action {
714                                 } else {
715                                         msg_events.push(events::MessageSendEvent::HandleError {
716                                                 node_id: $counterparty_node_id,
717                                                 action: err.action.clone()
718                                         });
719                                 }
720
721                                 if !msg_events.is_empty() {
722                                         $self.channel_state.lock().unwrap().pending_msg_events.append(&mut msg_events);
723                                 }
724
725                                 // Return error in case higher-API need one
726                                 Err(err)
727                         },
728                 }
729         }
730 }
731
732 macro_rules! break_chan_entry {
733         ($self: ident, $res: expr, $channel_state: expr, $entry: expr) => {
734                 match $res {
735                         Ok(res) => res,
736                         Err(ChannelError::Ignore(msg)) => {
737                                 break Err(MsgHandleErrInternal::from_chan_no_close(ChannelError::Ignore(msg), $entry.key().clone()))
738                         },
739                         Err(ChannelError::Close(msg)) => {
740                                 log_trace!($self.logger, "Closing channel {} due to Close-required error: {}", log_bytes!($entry.key()[..]), msg);
741                                 let (channel_id, mut chan) = $entry.remove_entry();
742                                 if let Some(short_id) = chan.get_short_channel_id() {
743                                         $channel_state.short_to_id.remove(&short_id);
744                                 }
745                                 break Err(MsgHandleErrInternal::from_finish_shutdown(msg, channel_id, chan.force_shutdown(true), $self.get_channel_update(&chan).ok()))
746                         },
747                         Err(ChannelError::CloseDelayBroadcast(_)) => { panic!("Wait is only generated on receipt of channel_reestablish, which is handled by try_chan_entry, we don't bother to support it here"); }
748                 }
749         }
750 }
751
752 macro_rules! try_chan_entry {
753         ($self: ident, $res: expr, $channel_state: expr, $entry: expr) => {
754                 match $res {
755                         Ok(res) => res,
756                         Err(ChannelError::Ignore(msg)) => {
757                                 return Err(MsgHandleErrInternal::from_chan_no_close(ChannelError::Ignore(msg), $entry.key().clone()))
758                         },
759                         Err(ChannelError::Close(msg)) => {
760                                 log_trace!($self.logger, "Closing channel {} due to Close-required error: {}", log_bytes!($entry.key()[..]), msg);
761                                 let (channel_id, mut chan) = $entry.remove_entry();
762                                 if let Some(short_id) = chan.get_short_channel_id() {
763                                         $channel_state.short_to_id.remove(&short_id);
764                                 }
765                                 return Err(MsgHandleErrInternal::from_finish_shutdown(msg, channel_id, chan.force_shutdown(true), $self.get_channel_update(&chan).ok()))
766                         },
767                         Err(ChannelError::CloseDelayBroadcast(msg)) => {
768                                 log_error!($self.logger, "Channel {} need to be shutdown but closing transactions not broadcast due to {}", log_bytes!($entry.key()[..]), msg);
769                                 let (channel_id, mut chan) = $entry.remove_entry();
770                                 if let Some(short_id) = chan.get_short_channel_id() {
771                                         $channel_state.short_to_id.remove(&short_id);
772                                 }
773                                 let shutdown_res = chan.force_shutdown(false);
774                                 return Err(MsgHandleErrInternal::from_finish_shutdown(msg, channel_id, shutdown_res, $self.get_channel_update(&chan).ok()))
775                         }
776                 }
777         }
778 }
779
780 macro_rules! handle_monitor_err {
781         ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $resend_raa: expr, $resend_commitment: expr) => {
782                 handle_monitor_err!($self, $err, $channel_state, $entry, $action_type, $resend_raa, $resend_commitment, Vec::new(), Vec::new())
783         };
784         ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $resend_raa: expr, $resend_commitment: expr, $failed_forwards: expr, $failed_fails: expr) => {
785                 match $err {
786                         ChannelMonitorUpdateErr::PermanentFailure => {
787                                 log_error!($self.logger, "Closing channel {} due to monitor update PermanentFailure", log_bytes!($entry.key()[..]));
788                                 let (channel_id, mut chan) = $entry.remove_entry();
789                                 if let Some(short_id) = chan.get_short_channel_id() {
790                                         $channel_state.short_to_id.remove(&short_id);
791                                 }
792                                 // TODO: $failed_fails is dropped here, which will cause other channels to hit the
793                                 // chain in a confused state! We need to move them into the ChannelMonitor which
794                                 // will be responsible for failing backwards once things confirm on-chain.
795                                 // It's ok that we drop $failed_forwards here - at this point we'd rather they
796                                 // broadcast HTLC-Timeout and pay the associated fees to get their funds back than
797                                 // us bother trying to claim it just to forward on to another peer. If we're
798                                 // splitting hairs we'd prefer to claim payments that were to us, but we haven't
799                                 // given up the preimage yet, so might as well just wait until the payment is
800                                 // retried, avoiding the on-chain fees.
801                                 let res: Result<(), _> = Err(MsgHandleErrInternal::from_finish_shutdown("ChannelMonitor storage failure".to_owned(), channel_id, chan.force_shutdown(true), $self.get_channel_update(&chan).ok()));
802                                 res
803                         },
804                         ChannelMonitorUpdateErr::TemporaryFailure => {
805                                 log_info!($self.logger, "Disabling channel {} due to monitor update TemporaryFailure. On restore will send {} and process {} forwards and {} fails",
806                                                 log_bytes!($entry.key()[..]),
807                                                 if $resend_commitment && $resend_raa {
808                                                                 match $action_type {
809                                                                         RAACommitmentOrder::CommitmentFirst => { "commitment then RAA" },
810                                                                         RAACommitmentOrder::RevokeAndACKFirst => { "RAA then commitment" },
811                                                                 }
812                                                         } else if $resend_commitment { "commitment" }
813                                                         else if $resend_raa { "RAA" }
814                                                         else { "nothing" },
815                                                 (&$failed_forwards as &Vec<(PendingHTLCInfo, u64)>).len(),
816                                                 (&$failed_fails as &Vec<(HTLCSource, PaymentHash, HTLCFailReason)>).len());
817                                 if !$resend_commitment {
818                                         debug_assert!($action_type == RAACommitmentOrder::RevokeAndACKFirst || !$resend_raa);
819                                 }
820                                 if !$resend_raa {
821                                         debug_assert!($action_type == RAACommitmentOrder::CommitmentFirst || !$resend_commitment);
822                                 }
823                                 $entry.get_mut().monitor_update_failed($resend_raa, $resend_commitment, $failed_forwards, $failed_fails);
824                                 Err(MsgHandleErrInternal::from_chan_no_close(ChannelError::Ignore("Failed to update ChannelMonitor".to_owned()), *$entry.key()))
825                         },
826                 }
827         }
828 }
829
830 macro_rules! return_monitor_err {
831         ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $resend_raa: expr, $resend_commitment: expr) => {
832                 return handle_monitor_err!($self, $err, $channel_state, $entry, $action_type, $resend_raa, $resend_commitment);
833         };
834         ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $resend_raa: expr, $resend_commitment: expr, $failed_forwards: expr, $failed_fails: expr) => {
835                 return handle_monitor_err!($self, $err, $channel_state, $entry, $action_type, $resend_raa, $resend_commitment, $failed_forwards, $failed_fails);
836         }
837 }
838
839 // Does not break in case of TemporaryFailure!
840 macro_rules! maybe_break_monitor_err {
841         ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $resend_raa: expr, $resend_commitment: expr) => {
842                 match (handle_monitor_err!($self, $err, $channel_state, $entry, $action_type, $resend_raa, $resend_commitment), $err) {
843                         (e, ChannelMonitorUpdateErr::PermanentFailure) => {
844                                 break e;
845                         },
846                         (_, ChannelMonitorUpdateErr::TemporaryFailure) => { },
847                 }
848         }
849 }
850
851 impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelManager<Signer, M, T, K, F, L>
852         where M::Target: chain::Watch<Signer>,
853         T::Target: BroadcasterInterface,
854         K::Target: KeysInterface<Signer = Signer>,
855         F::Target: FeeEstimator,
856         L::Target: Logger,
857 {
858         /// Constructs a new ChannelManager to hold several channels and route between them.
859         ///
860         /// This is the main "logic hub" for all channel-related actions, and implements
861         /// ChannelMessageHandler.
862         ///
863         /// Non-proportional fees are fixed according to our risk using the provided fee estimator.
864         ///
865         /// panics if channel_value_satoshis is >= `MAX_FUNDING_SATOSHIS`!
866         ///
867         /// Users need to notify the new ChannelManager when a new block is connected or
868         /// disconnected using its `block_connected` and `block_disconnected` methods, starting
869         /// from after `params.latest_hash`.
870         pub fn new(fee_est: F, chain_monitor: M, tx_broadcaster: T, logger: L, keys_manager: K, config: UserConfig, params: ChainParameters) -> Self {
871                 let mut secp_ctx = Secp256k1::new();
872                 secp_ctx.seeded_randomize(&keys_manager.get_secure_random_bytes());
873
874                 ChannelManager {
875                         default_configuration: config.clone(),
876                         genesis_hash: genesis_block(params.network).header.block_hash(),
877                         fee_estimator: fee_est,
878                         chain_monitor,
879                         tx_broadcaster,
880
881                         best_block: RwLock::new(params.best_block),
882
883                         channel_state: Mutex::new(ChannelHolder{
884                                 by_id: HashMap::new(),
885                                 short_to_id: HashMap::new(),
886                                 forward_htlcs: HashMap::new(),
887                                 claimable_htlcs: HashMap::new(),
888                                 pending_msg_events: Vec::new(),
889                         }),
890                         pending_inbound_payments: Mutex::new(HashMap::new()),
891
892                         our_network_key: keys_manager.get_node_secret(),
893                         our_network_pubkey: PublicKey::from_secret_key(&secp_ctx, &keys_manager.get_node_secret()),
894                         secp_ctx,
895
896                         last_node_announcement_serial: AtomicUsize::new(0),
897                         highest_seen_timestamp: AtomicUsize::new(0),
898
899                         per_peer_state: RwLock::new(HashMap::new()),
900
901                         pending_events: Mutex::new(Vec::new()),
902                         pending_background_events: Mutex::new(Vec::new()),
903                         total_consistency_lock: RwLock::new(()),
904                         persistence_notifier: PersistenceNotifier::new(),
905
906                         keys_manager,
907
908                         logger,
909                 }
910         }
911
912         /// Gets the current configuration applied to all new channels,  as
913         pub fn get_current_default_configuration(&self) -> &UserConfig {
914                 &self.default_configuration
915         }
916
917         /// Creates a new outbound channel to the given remote node and with the given value.
918         ///
919         /// user_id will be provided back as user_channel_id in FundingGenerationReady events to allow
920         /// tracking of which events correspond with which create_channel call. Note that the
921         /// user_channel_id defaults to 0 for inbound channels, so you may wish to avoid using 0 for
922         /// user_id here. user_id has no meaning inside of LDK, it is simply copied to events and
923         /// otherwise ignored.
924         ///
925         /// If successful, will generate a SendOpenChannel message event, so you should probably poll
926         /// PeerManager::process_events afterwards.
927         ///
928         /// Raises APIError::APIMisuseError when channel_value_satoshis > 2**24 or push_msat is
929         /// greater than channel_value_satoshis * 1k or channel_value_satoshis is < 1000.
930         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> {
931                 if channel_value_satoshis < 1000 {
932                         return Err(APIError::APIMisuseError { err: format!("Channel value must be at least 1000 satoshis. It was {}", channel_value_satoshis) });
933                 }
934
935                 let config = if override_config.is_some() { override_config.as_ref().unwrap() } else { &self.default_configuration };
936                 let channel = Channel::new_outbound(&self.fee_estimator, &self.keys_manager, their_network_key, channel_value_satoshis, push_msat, user_id, config)?;
937                 let res = channel.get_open_channel(self.genesis_hash.clone());
938
939                 let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
940                 // We want to make sure the lock is actually acquired by PersistenceNotifierGuard.
941                 debug_assert!(&self.total_consistency_lock.try_write().is_err());
942
943                 let mut channel_state = self.channel_state.lock().unwrap();
944                 match channel_state.by_id.entry(channel.channel_id()) {
945                         hash_map::Entry::Occupied(_) => {
946                                 if cfg!(feature = "fuzztarget") {
947                                         return Err(APIError::APIMisuseError { err: "Fuzzy bad RNG".to_owned() });
948                                 } else {
949                                         panic!("RNG is bad???");
950                                 }
951                         },
952                         hash_map::Entry::Vacant(entry) => { entry.insert(channel); }
953                 }
954                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendOpenChannel {
955                         node_id: their_network_key,
956                         msg: res,
957                 });
958                 Ok(())
959         }
960
961         fn list_channels_with_filter<Fn: FnMut(&(&[u8; 32], &Channel<Signer>)) -> bool>(&self, f: Fn) -> Vec<ChannelDetails> {
962                 let mut res = Vec::new();
963                 {
964                         let channel_state = self.channel_state.lock().unwrap();
965                         res.reserve(channel_state.by_id.len());
966                         for (channel_id, channel) in channel_state.by_id.iter().filter(f) {
967                                 let (inbound_capacity_msat, outbound_capacity_msat) = channel.get_inbound_outbound_available_balance_msat();
968                                 res.push(ChannelDetails {
969                                         channel_id: (*channel_id).clone(),
970                                         short_channel_id: channel.get_short_channel_id(),
971                                         remote_network_id: channel.get_counterparty_node_id(),
972                                         counterparty_features: InitFeatures::empty(),
973                                         channel_value_satoshis: channel.get_value_satoshis(),
974                                         inbound_capacity_msat,
975                                         outbound_capacity_msat,
976                                         user_id: channel.get_user_id(),
977                                         is_live: channel.is_live(),
978                                         counterparty_forwarding_info: channel.counterparty_forwarding_info(),
979                                 });
980                         }
981                 }
982                 let per_peer_state = self.per_peer_state.read().unwrap();
983                 for chan in res.iter_mut() {
984                         if let Some(peer_state) = per_peer_state.get(&chan.remote_network_id) {
985                                 chan.counterparty_features = peer_state.lock().unwrap().latest_features.clone();
986                         }
987                 }
988                 res
989         }
990
991         /// Gets the list of open channels, in random order. See ChannelDetail field documentation for
992         /// more information.
993         pub fn list_channels(&self) -> Vec<ChannelDetails> {
994                 self.list_channels_with_filter(|_| true)
995         }
996
997         /// Gets the list of usable channels, in random order. Useful as an argument to
998         /// get_route to ensure non-announced channels are used.
999         ///
1000         /// These are guaranteed to have their is_live value set to true, see the documentation for
1001         /// ChannelDetails::is_live for more info on exactly what the criteria are.
1002         pub fn list_usable_channels(&self) -> Vec<ChannelDetails> {
1003                 // Note we use is_live here instead of usable which leads to somewhat confused
1004                 // internal/external nomenclature, but that's ok cause that's probably what the user
1005                 // really wanted anyway.
1006                 self.list_channels_with_filter(|&(_, ref channel)| channel.is_live())
1007         }
1008
1009         /// Begins the process of closing a channel. After this call (plus some timeout), no new HTLCs
1010         /// will be accepted on the given channel, and after additional timeout/the closing of all
1011         /// pending HTLCs, the channel will be closed on chain.
1012         ///
1013         /// May generate a SendShutdown message event on success, which should be relayed.
1014         pub fn close_channel(&self, channel_id: &[u8; 32]) -> Result<(), APIError> {
1015                 let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
1016
1017                 let (mut failed_htlcs, chan_option) = {
1018                         let mut channel_state_lock = self.channel_state.lock().unwrap();
1019                         let channel_state = &mut *channel_state_lock;
1020                         match channel_state.by_id.entry(channel_id.clone()) {
1021                                 hash_map::Entry::Occupied(mut chan_entry) => {
1022                                         let (shutdown_msg, failed_htlcs) = chan_entry.get_mut().get_shutdown()?;
1023                                         channel_state.pending_msg_events.push(events::MessageSendEvent::SendShutdown {
1024                                                 node_id: chan_entry.get().get_counterparty_node_id(),
1025                                                 msg: shutdown_msg
1026                                         });
1027                                         if chan_entry.get().is_shutdown() {
1028                                                 if let Some(short_id) = chan_entry.get().get_short_channel_id() {
1029                                                         channel_state.short_to_id.remove(&short_id);
1030                                                 }
1031                                                 (failed_htlcs, Some(chan_entry.remove_entry().1))
1032                                         } else { (failed_htlcs, None) }
1033                                 },
1034                                 hash_map::Entry::Vacant(_) => return Err(APIError::ChannelUnavailable{err: "No such channel".to_owned()})
1035                         }
1036                 };
1037                 for htlc_source in failed_htlcs.drain(..) {
1038                         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() });
1039                 }
1040                 let chan_update = if let Some(chan) = chan_option {
1041                         if let Ok(update) = self.get_channel_update(&chan) {
1042                                 Some(update)
1043                         } else { None }
1044                 } else { None };
1045
1046                 if let Some(update) = chan_update {
1047                         let mut channel_state = self.channel_state.lock().unwrap();
1048                         channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
1049                                 msg: update
1050                         });
1051                 }
1052
1053                 Ok(())
1054         }
1055
1056         #[inline]
1057         fn finish_force_close_channel(&self, shutdown_res: ShutdownResult) {
1058                 let (monitor_update_option, mut failed_htlcs) = shutdown_res;
1059                 log_trace!(self.logger, "Finishing force-closure of channel {} HTLCs to fail", failed_htlcs.len());
1060                 for htlc_source in failed_htlcs.drain(..) {
1061                         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() });
1062                 }
1063                 if let Some((funding_txo, monitor_update)) = monitor_update_option {
1064                         // There isn't anything we can do if we get an update failure - we're already
1065                         // force-closing. The monitor update on the required in-memory copy should broadcast
1066                         // the latest local state, which is the best we can do anyway. Thus, it is safe to
1067                         // ignore the result here.
1068                         let _ = self.chain_monitor.update_channel(funding_txo, monitor_update);
1069                 }
1070         }
1071
1072         fn force_close_channel_with_peer(&self, channel_id: &[u8; 32], peer_node_id: Option<&PublicKey>) -> Result<PublicKey, APIError> {
1073                 let mut chan = {
1074                         let mut channel_state_lock = self.channel_state.lock().unwrap();
1075                         let channel_state = &mut *channel_state_lock;
1076                         if let hash_map::Entry::Occupied(chan) = channel_state.by_id.entry(channel_id.clone()) {
1077                                 if let Some(node_id) = peer_node_id {
1078                                         if chan.get().get_counterparty_node_id() != *node_id {
1079                                                 return Err(APIError::ChannelUnavailable{err: "No such channel".to_owned()});
1080                                         }
1081                                 }
1082                                 if let Some(short_id) = chan.get().get_short_channel_id() {
1083                                         channel_state.short_to_id.remove(&short_id);
1084                                 }
1085                                 chan.remove_entry().1
1086                         } else {
1087                                 return Err(APIError::ChannelUnavailable{err: "No such channel".to_owned()});
1088                         }
1089                 };
1090                 log_trace!(self.logger, "Force-closing channel {}", log_bytes!(channel_id[..]));
1091                 self.finish_force_close_channel(chan.force_shutdown(true));
1092                 if let Ok(update) = self.get_channel_update(&chan) {
1093                         let mut channel_state = self.channel_state.lock().unwrap();
1094                         channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
1095                                 msg: update
1096                         });
1097                 }
1098
1099                 Ok(chan.get_counterparty_node_id())
1100         }
1101
1102         /// Force closes a channel, immediately broadcasting the latest local commitment transaction to
1103         /// the chain and rejecting new HTLCs on the given channel. Fails if channel_id is unknown to the manager.
1104         pub fn force_close_channel(&self, channel_id: &[u8; 32]) -> Result<(), APIError> {
1105                 let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
1106                 match self.force_close_channel_with_peer(channel_id, None) {
1107                         Ok(counterparty_node_id) => {
1108                                 self.channel_state.lock().unwrap().pending_msg_events.push(
1109                                         events::MessageSendEvent::HandleError {
1110                                                 node_id: counterparty_node_id,
1111                                                 action: msgs::ErrorAction::SendErrorMessage {
1112                                                         msg: msgs::ErrorMessage { channel_id: *channel_id, data: "Channel force-closed".to_owned() }
1113                                                 },
1114                                         }
1115                                 );
1116                                 Ok(())
1117                         },
1118                         Err(e) => Err(e)
1119                 }
1120         }
1121
1122         /// Force close all channels, immediately broadcasting the latest local commitment transaction
1123         /// for each to the chain and rejecting new HTLCs on each.
1124         pub fn force_close_all_channels(&self) {
1125                 for chan in self.list_channels() {
1126                         let _ = self.force_close_channel(&chan.channel_id);
1127                 }
1128         }
1129
1130         fn decode_update_add_htlc_onion(&self, msg: &msgs::UpdateAddHTLC) -> (PendingHTLCStatus, MutexGuard<ChannelHolder<Signer>>) {
1131                 macro_rules! return_malformed_err {
1132                         ($msg: expr, $err_code: expr) => {
1133                                 {
1134                                         log_info!(self.logger, "Failed to accept/forward incoming HTLC: {}", $msg);
1135                                         return (PendingHTLCStatus::Fail(HTLCFailureMsg::Malformed(msgs::UpdateFailMalformedHTLC {
1136                                                 channel_id: msg.channel_id,
1137                                                 htlc_id: msg.htlc_id,
1138                                                 sha256_of_onion: Sha256::hash(&msg.onion_routing_packet.hop_data).into_inner(),
1139                                                 failure_code: $err_code,
1140                                         })), self.channel_state.lock().unwrap());
1141                                 }
1142                         }
1143                 }
1144
1145                 if let Err(_) = msg.onion_routing_packet.public_key {
1146                         return_malformed_err!("invalid ephemeral pubkey", 0x8000 | 0x4000 | 6);
1147                 }
1148
1149                 let shared_secret = {
1150                         let mut arr = [0; 32];
1151                         arr.copy_from_slice(&SharedSecret::new(&msg.onion_routing_packet.public_key.unwrap(), &self.our_network_key)[..]);
1152                         arr
1153                 };
1154                 let (rho, mu) = onion_utils::gen_rho_mu_from_shared_secret(&shared_secret);
1155
1156                 if msg.onion_routing_packet.version != 0 {
1157                         //TODO: Spec doesn't indicate if we should only hash hop_data here (and in other
1158                         //sha256_of_onion error data packets), or the entire onion_routing_packet. Either way,
1159                         //the hash doesn't really serve any purpose - in the case of hashing all data, the
1160                         //receiving node would have to brute force to figure out which version was put in the
1161                         //packet by the node that send us the message, in the case of hashing the hop_data, the
1162                         //node knows the HMAC matched, so they already know what is there...
1163                         return_malformed_err!("Unknown onion packet version", 0x8000 | 0x4000 | 4);
1164                 }
1165
1166                 let mut hmac = HmacEngine::<Sha256>::new(&mu);
1167                 hmac.input(&msg.onion_routing_packet.hop_data);
1168                 hmac.input(&msg.payment_hash.0[..]);
1169                 if !fixed_time_eq(&Hmac::from_engine(hmac).into_inner(), &msg.onion_routing_packet.hmac) {
1170                         return_malformed_err!("HMAC Check failed", 0x8000 | 0x4000 | 5);
1171                 }
1172
1173                 let mut channel_state = None;
1174                 macro_rules! return_err {
1175                         ($msg: expr, $err_code: expr, $data: expr) => {
1176                                 {
1177                                         log_info!(self.logger, "Failed to accept/forward incoming HTLC: {}", $msg);
1178                                         if channel_state.is_none() {
1179                                                 channel_state = Some(self.channel_state.lock().unwrap());
1180                                         }
1181                                         return (PendingHTLCStatus::Fail(HTLCFailureMsg::Relay(msgs::UpdateFailHTLC {
1182                                                 channel_id: msg.channel_id,
1183                                                 htlc_id: msg.htlc_id,
1184                                                 reason: onion_utils::build_first_hop_failure_packet(&shared_secret, $err_code, $data),
1185                                         })), channel_state.unwrap());
1186                                 }
1187                         }
1188                 }
1189
1190                 let mut chacha = ChaCha20::new(&rho, &[0u8; 8]);
1191                 let mut chacha_stream = ChaChaReader { chacha: &mut chacha, read: Cursor::new(&msg.onion_routing_packet.hop_data[..]) };
1192                 let (next_hop_data, next_hop_hmac) = {
1193                         match msgs::OnionHopData::read(&mut chacha_stream) {
1194                                 Err(err) => {
1195                                         let error_code = match err {
1196                                                 msgs::DecodeError::UnknownVersion => 0x4000 | 1, // unknown realm byte
1197                                                 msgs::DecodeError::UnknownRequiredFeature|
1198                                                 msgs::DecodeError::InvalidValue|
1199                                                 msgs::DecodeError::ShortRead => 0x4000 | 22, // invalid_onion_payload
1200                                                 _ => 0x2000 | 2, // Should never happen
1201                                         };
1202                                         return_err!("Unable to decode our hop data", error_code, &[0;0]);
1203                                 },
1204                                 Ok(msg) => {
1205                                         let mut hmac = [0; 32];
1206                                         if let Err(_) = chacha_stream.read_exact(&mut hmac[..]) {
1207                                                 return_err!("Unable to decode hop data", 0x4000 | 22, &[0;0]);
1208                                         }
1209                                         (msg, hmac)
1210                                 },
1211                         }
1212                 };
1213
1214                 let pending_forward_info = if next_hop_hmac == [0; 32] {
1215                                 #[cfg(test)]
1216                                 {
1217                                         // In tests, make sure that the initial onion pcket data is, at least, non-0.
1218                                         // We could do some fancy randomness test here, but, ehh, whatever.
1219                                         // This checks for the issue where you can calculate the path length given the
1220                                         // onion data as all the path entries that the originator sent will be here
1221                                         // as-is (and were originally 0s).
1222                                         // Of course reverse path calculation is still pretty easy given naive routing
1223                                         // algorithms, but this fixes the most-obvious case.
1224                                         let mut next_bytes = [0; 32];
1225                                         chacha_stream.read_exact(&mut next_bytes).unwrap();
1226                                         assert_ne!(next_bytes[..], [0; 32][..]);
1227                                         chacha_stream.read_exact(&mut next_bytes).unwrap();
1228                                         assert_ne!(next_bytes[..], [0; 32][..]);
1229                                 }
1230
1231                                 // OUR PAYMENT!
1232                                 // final_expiry_too_soon
1233                                 // We have to have some headroom to broadcast on chain if we have the preimage, so make sure we have at least
1234                                 // HTLC_FAIL_BACK_BUFFER blocks to go.
1235                                 // Also, ensure that, in the case of an unknown payment hash, our payment logic has enough time to fail the HTLC backward
1236                                 // before our onchain logic triggers a channel closure (see HTLC_FAIL_BACK_BUFFER rational).
1237                                 if (msg.cltv_expiry as u64) <= self.best_block.read().unwrap().height() as u64 + HTLC_FAIL_BACK_BUFFER as u64 + 1 {
1238                                         return_err!("The final CLTV expiry is too soon to handle", 17, &[0;0]);
1239                                 }
1240                                 // final_incorrect_htlc_amount
1241                                 if next_hop_data.amt_to_forward > msg.amount_msat {
1242                                         return_err!("Upstream node sent less than we were supposed to receive in payment", 19, &byte_utils::be64_to_array(msg.amount_msat));
1243                                 }
1244                                 // final_incorrect_cltv_expiry
1245                                 if next_hop_data.outgoing_cltv_value != msg.cltv_expiry {
1246                                         return_err!("Upstream node set CLTV to the wrong value", 18, &byte_utils::be32_to_array(msg.cltv_expiry));
1247                                 }
1248
1249                                 let payment_data = match next_hop_data.format {
1250                                         msgs::OnionHopDataFormat::Legacy { .. } => None,
1251                                         msgs::OnionHopDataFormat::NonFinalNode { .. } => return_err!("Got non final data with an HMAC of 0", 0x4000 | 22, &[0;0]),
1252                                         msgs::OnionHopDataFormat::FinalNode { payment_data } => payment_data,
1253                                 };
1254
1255                                 if payment_data.is_none() {
1256                                         return_err!("We require payment_secrets", 0x4000|0x2000|3, &[0;0]);
1257                                 }
1258
1259                                 // Note that we could obviously respond immediately with an update_fulfill_htlc
1260                                 // message, however that would leak that we are the recipient of this payment, so
1261                                 // instead we stay symmetric with the forwarding case, only responding (after a
1262                                 // delay) once they've send us a commitment_signed!
1263
1264                                 PendingHTLCStatus::Forward(PendingHTLCInfo {
1265                                         routing: PendingHTLCRouting::Receive {
1266                                                 payment_data: payment_data.unwrap(),
1267                                                 incoming_cltv_expiry: msg.cltv_expiry,
1268                                         },
1269                                         payment_hash: msg.payment_hash.clone(),
1270                                         incoming_shared_secret: shared_secret,
1271                                         amt_to_forward: next_hop_data.amt_to_forward,
1272                                         outgoing_cltv_value: next_hop_data.outgoing_cltv_value,
1273                                 })
1274                         } else {
1275                                 let mut new_packet_data = [0; 20*65];
1276                                 let read_pos = chacha_stream.read(&mut new_packet_data).unwrap();
1277                                 #[cfg(debug_assertions)]
1278                                 {
1279                                         // Check two things:
1280                                         // a) that the behavior of our stream here will return Ok(0) even if the TLV
1281                                         //    read above emptied out our buffer and the unwrap() wont needlessly panic
1282                                         // b) that we didn't somehow magically end up with extra data.
1283                                         let mut t = [0; 1];
1284                                         debug_assert!(chacha_stream.read(&mut t).unwrap() == 0);
1285                                 }
1286                                 // Once we've emptied the set of bytes our peer gave us, encrypt 0 bytes until we
1287                                 // fill the onion hop data we'll forward to our next-hop peer.
1288                                 chacha_stream.chacha.process_in_place(&mut new_packet_data[read_pos..]);
1289
1290                                 let mut new_pubkey = msg.onion_routing_packet.public_key.unwrap();
1291
1292                                 let blinding_factor = {
1293                                         let mut sha = Sha256::engine();
1294                                         sha.input(&new_pubkey.serialize()[..]);
1295                                         sha.input(&shared_secret);
1296                                         Sha256::from_engine(sha).into_inner()
1297                                 };
1298
1299                                 let public_key = if let Err(e) = new_pubkey.mul_assign(&self.secp_ctx, &blinding_factor[..]) {
1300                                         Err(e)
1301                                 } else { Ok(new_pubkey) };
1302
1303                                 let outgoing_packet = msgs::OnionPacket {
1304                                         version: 0,
1305                                         public_key,
1306                                         hop_data: new_packet_data,
1307                                         hmac: next_hop_hmac.clone(),
1308                                 };
1309
1310                                 let short_channel_id = match next_hop_data.format {
1311                                         msgs::OnionHopDataFormat::Legacy { short_channel_id } => short_channel_id,
1312                                         msgs::OnionHopDataFormat::NonFinalNode { short_channel_id } => short_channel_id,
1313                                         msgs::OnionHopDataFormat::FinalNode { .. } => {
1314                                                 return_err!("Final Node OnionHopData provided for us as an intermediary node", 0x4000 | 22, &[0;0]);
1315                                         },
1316                                 };
1317
1318                                 PendingHTLCStatus::Forward(PendingHTLCInfo {
1319                                         routing: PendingHTLCRouting::Forward {
1320                                                 onion_packet: outgoing_packet,
1321                                                 short_channel_id,
1322                                         },
1323                                         payment_hash: msg.payment_hash.clone(),
1324                                         incoming_shared_secret: shared_secret,
1325                                         amt_to_forward: next_hop_data.amt_to_forward,
1326                                         outgoing_cltv_value: next_hop_data.outgoing_cltv_value,
1327                                 })
1328                         };
1329
1330                 channel_state = Some(self.channel_state.lock().unwrap());
1331                 if let &PendingHTLCStatus::Forward(PendingHTLCInfo { ref routing, ref amt_to_forward, ref outgoing_cltv_value, .. }) = &pending_forward_info {
1332                         // If short_channel_id is 0 here, we'll reject the HTLC as there cannot be a channel
1333                         // with a short_channel_id of 0. This is important as various things later assume
1334                         // short_channel_id is non-0 in any ::Forward.
1335                         if let &PendingHTLCRouting::Forward { ref short_channel_id, .. } = routing {
1336                                 let id_option = channel_state.as_ref().unwrap().short_to_id.get(&short_channel_id).cloned();
1337                                 let forwarding_id = match id_option {
1338                                         None => { // unknown_next_peer
1339                                                 return_err!("Don't have available channel for forwarding as requested.", 0x4000 | 10, &[0;0]);
1340                                         },
1341                                         Some(id) => id.clone(),
1342                                 };
1343                                 if let Some((err, code, chan_update)) = loop {
1344                                         let chan = channel_state.as_mut().unwrap().by_id.get_mut(&forwarding_id).unwrap();
1345
1346                                         // Note that we could technically not return an error yet here and just hope
1347                                         // that the connection is reestablished or monitor updated by the time we get
1348                                         // around to doing the actual forward, but better to fail early if we can and
1349                                         // hopefully an attacker trying to path-trace payments cannot make this occur
1350                                         // on a small/per-node/per-channel scale.
1351                                         if !chan.is_live() { // channel_disabled
1352                                                 break Some(("Forwarding channel is not in a ready state.", 0x1000 | 20, Some(self.get_channel_update(chan).unwrap())));
1353                                         }
1354                                         if *amt_to_forward < chan.get_counterparty_htlc_minimum_msat() { // amount_below_minimum
1355                                                 break Some(("HTLC amount was below the htlc_minimum_msat", 0x1000 | 11, Some(self.get_channel_update(chan).unwrap())));
1356                                         }
1357                                         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) });
1358                                         if fee.is_none() || msg.amount_msat < fee.unwrap() || (msg.amount_msat - fee.unwrap()) < *amt_to_forward { // fee_insufficient
1359                                                 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())));
1360                                         }
1361                                         if (msg.cltv_expiry as u64) < (*outgoing_cltv_value) as u64 + chan.get_cltv_expiry_delta() as u64 { // incorrect_cltv_expiry
1362                                                 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())));
1363                                         }
1364                                         let cur_height = self.best_block.read().unwrap().height() + 1;
1365                                         // Theoretically, channel counterparty shouldn't send us a HTLC expiring now, but we want to be robust wrt to counterparty
1366                                         // packet sanitization (see HTLC_FAIL_BACK_BUFFER rational)
1367                                         if msg.cltv_expiry <= cur_height + HTLC_FAIL_BACK_BUFFER as u32 { // expiry_too_soon
1368                                                 break Some(("CLTV expiry is too close", 0x1000 | 14, Some(self.get_channel_update(chan).unwrap())));
1369                                         }
1370                                         if msg.cltv_expiry > cur_height + CLTV_FAR_FAR_AWAY as u32 { // expiry_too_far
1371                                                 break Some(("CLTV expiry is too far in the future", 21, None));
1372                                         }
1373                                         // In theory, we would be safe against unitentional channel-closure, if we only required a margin of LATENCY_GRACE_PERIOD_BLOCKS.
1374                                         // But, to be safe against policy reception, we use a longuer delay.
1375                                         if (*outgoing_cltv_value) as u64 <= (cur_height + HTLC_FAIL_BACK_BUFFER) as u64 {
1376                                                 break Some(("Outgoing CLTV value is too soon", 0x1000 | 14, Some(self.get_channel_update(chan).unwrap())));
1377                                         }
1378
1379                                         break None;
1380                                 }
1381                                 {
1382                                         let mut res = Vec::with_capacity(8 + 128);
1383                                         if let Some(chan_update) = chan_update {
1384                                                 if code == 0x1000 | 11 || code == 0x1000 | 12 {
1385                                                         res.extend_from_slice(&byte_utils::be64_to_array(msg.amount_msat));
1386                                                 }
1387                                                 else if code == 0x1000 | 13 {
1388                                                         res.extend_from_slice(&byte_utils::be32_to_array(msg.cltv_expiry));
1389                                                 }
1390                                                 else if code == 0x1000 | 20 {
1391                                                         // TODO: underspecified, follow https://github.com/lightningnetwork/lightning-rfc/issues/791
1392                                                         res.extend_from_slice(&byte_utils::be16_to_array(0));
1393                                                 }
1394                                                 res.extend_from_slice(&chan_update.encode_with_len()[..]);
1395                                         }
1396                                         return_err!(err, code, &res[..]);
1397                                 }
1398                         }
1399                 }
1400
1401                 (pending_forward_info, channel_state.unwrap())
1402         }
1403
1404         /// only fails if the channel does not yet have an assigned short_id
1405         /// May be called with channel_state already locked!
1406         fn get_channel_update(&self, chan: &Channel<Signer>) -> Result<msgs::ChannelUpdate, LightningError> {
1407                 let short_channel_id = match chan.get_short_channel_id() {
1408                         None => return Err(LightningError{err: "Channel not yet established".to_owned(), action: msgs::ErrorAction::IgnoreError}),
1409                         Some(id) => id,
1410                 };
1411
1412                 let were_node_one = PublicKey::from_secret_key(&self.secp_ctx, &self.our_network_key).serialize()[..] < chan.get_counterparty_node_id().serialize()[..];
1413
1414                 let unsigned = msgs::UnsignedChannelUpdate {
1415                         chain_hash: self.genesis_hash,
1416                         short_channel_id,
1417                         timestamp: chan.get_update_time_counter(),
1418                         flags: (!were_node_one) as u8 | ((!chan.is_live() as u8) << 1),
1419                         cltv_expiry_delta: chan.get_cltv_expiry_delta(),
1420                         htlc_minimum_msat: chan.get_counterparty_htlc_minimum_msat(),
1421                         htlc_maximum_msat: OptionalField::Present(chan.get_announced_htlc_max_msat()),
1422                         fee_base_msat: chan.get_holder_fee_base_msat(&self.fee_estimator),
1423                         fee_proportional_millionths: chan.get_fee_proportional_millionths(),
1424                         excess_data: Vec::new(),
1425                 };
1426
1427                 let msg_hash = Sha256dHash::hash(&unsigned.encode()[..]);
1428                 let sig = self.secp_ctx.sign(&hash_to_message!(&msg_hash[..]), &self.our_network_key);
1429
1430                 Ok(msgs::ChannelUpdate {
1431                         signature: sig,
1432                         contents: unsigned
1433                 })
1434         }
1435
1436         // Only public for testing, this should otherwise never be called direcly
1437         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> {
1438                 log_trace!(self.logger, "Attempting to send payment for path with next hop {}", path.first().unwrap().short_channel_id);
1439                 let prng_seed = self.keys_manager.get_secure_random_bytes();
1440                 let session_priv = SecretKey::from_slice(&self.keys_manager.get_secure_random_bytes()[..]).expect("RNG is busted");
1441
1442                 let onion_keys = onion_utils::construct_onion_keys(&self.secp_ctx, &path, &session_priv)
1443                         .map_err(|_| APIError::RouteError{err: "Pubkey along hop was maliciously selected"})?;
1444                 let (onion_payloads, htlc_msat, htlc_cltv) = onion_utils::build_onion_payloads(path, total_value, payment_secret, cur_height)?;
1445                 if onion_utils::route_size_insane(&onion_payloads) {
1446                         return Err(APIError::RouteError{err: "Route size too large considering onion data"});
1447                 }
1448                 let onion_packet = onion_utils::construct_onion_packet(onion_payloads, onion_keys, prng_seed, payment_hash);
1449
1450                 let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
1451
1452                 let err: Result<(), _> = loop {
1453                         let mut channel_lock = self.channel_state.lock().unwrap();
1454                         let id = match channel_lock.short_to_id.get(&path.first().unwrap().short_channel_id) {
1455                                 None => return Err(APIError::ChannelUnavailable{err: "No channel available with first hop!".to_owned()}),
1456                                 Some(id) => id.clone(),
1457                         };
1458
1459                         let channel_state = &mut *channel_lock;
1460                         if let hash_map::Entry::Occupied(mut chan) = channel_state.by_id.entry(id) {
1461                                 match {
1462                                         if chan.get().get_counterparty_node_id() != path.first().unwrap().pubkey {
1463                                                 return Err(APIError::RouteError{err: "Node ID mismatch on first hop!"});
1464                                         }
1465                                         if !chan.get().is_live() {
1466                                                 return Err(APIError::ChannelUnavailable{err: "Peer for first hop currently disconnected/pending monitor update!".to_owned()});
1467                                         }
1468                                         break_chan_entry!(self, chan.get_mut().send_htlc_and_commit(htlc_msat, payment_hash.clone(), htlc_cltv, HTLCSource::OutboundRoute {
1469                                                 path: path.clone(),
1470                                                 session_priv: session_priv.clone(),
1471                                                 first_hop_htlc_msat: htlc_msat,
1472                                         }, onion_packet, &self.logger), channel_state, chan)
1473                                 } {
1474                                         Some((update_add, commitment_signed, monitor_update)) => {
1475                                                 if let Err(e) = self.chain_monitor.update_channel(chan.get().get_funding_txo().unwrap(), monitor_update) {
1476                                                         maybe_break_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::CommitmentFirst, false, true);
1477                                                         // Note that MonitorUpdateFailed here indicates (per function docs)
1478                                                         // that we will resend the commitment update once monitor updating
1479                                                         // is restored. Therefore, we must return an error indicating that
1480                                                         // it is unsafe to retry the payment wholesale, which we do in the
1481                                                         // send_payment check for MonitorUpdateFailed, below.
1482                                                         return Err(APIError::MonitorUpdateFailed);
1483                                                 }
1484
1485                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
1486                                                         node_id: path.first().unwrap().pubkey,
1487                                                         updates: msgs::CommitmentUpdate {
1488                                                                 update_add_htlcs: vec![update_add],
1489                                                                 update_fulfill_htlcs: Vec::new(),
1490                                                                 update_fail_htlcs: Vec::new(),
1491                                                                 update_fail_malformed_htlcs: Vec::new(),
1492                                                                 update_fee: None,
1493                                                                 commitment_signed,
1494                                                         },
1495                                                 });
1496                                         },
1497                                         None => {},
1498                                 }
1499                         } else { unreachable!(); }
1500                         return Ok(());
1501                 };
1502
1503                 match handle_error!(self, err, path.first().unwrap().pubkey) {
1504                         Ok(_) => unreachable!(),
1505                         Err(e) => {
1506                                 Err(APIError::ChannelUnavailable { err: e.err })
1507                         },
1508                 }
1509         }
1510
1511         /// Sends a payment along a given route.
1512         ///
1513         /// Value parameters are provided via the last hop in route, see documentation for RouteHop
1514         /// fields for more info.
1515         ///
1516         /// Note that if the payment_hash already exists elsewhere (eg you're sending a duplicative
1517         /// payment), we don't do anything to stop you! We always try to ensure that if the provided
1518         /// next hop knows the preimage to payment_hash they can claim an additional amount as
1519         /// specified in the last hop in the route! Thus, you should probably do your own
1520         /// payment_preimage tracking (which you should already be doing as they represent "proof of
1521         /// payment") and prevent double-sends yourself.
1522         ///
1523         /// May generate SendHTLCs message(s) event on success, which should be relayed.
1524         ///
1525         /// Each path may have a different return value, and PaymentSendValue may return a Vec with
1526         /// each entry matching the corresponding-index entry in the route paths, see
1527         /// PaymentSendFailure for more info.
1528         ///
1529         /// In general, a path may raise:
1530         ///  * APIError::RouteError when an invalid route or forwarding parameter (cltv_delta, fee,
1531         ///    node public key) is specified.
1532         ///  * APIError::ChannelUnavailable if the next-hop channel is not available for updates
1533         ///    (including due to previous monitor update failure or new permanent monitor update
1534         ///    failure).
1535         ///  * APIError::MonitorUpdateFailed if a new monitor update failure prevented sending the
1536         ///    relevant updates.
1537         ///
1538         /// Note that depending on the type of the PaymentSendFailure the HTLC may have been
1539         /// irrevocably committed to on our end. In such a case, do NOT retry the payment with a
1540         /// different route unless you intend to pay twice!
1541         ///
1542         /// payment_secret is unrelated to payment_hash (or PaymentPreimage) and exists to authenticate
1543         /// the sender to the recipient and prevent payment-probing (deanonymization) attacks. For
1544         /// newer nodes, it will be provided to you in the invoice. If you do not have one, the Route
1545         /// must not contain multiple paths as multi-path payments require a recipient-provided
1546         /// payment_secret.
1547         /// If a payment_secret *is* provided, we assume that the invoice had the payment_secret feature
1548         /// bit set (either as required or as available). If multiple paths are present in the Route,
1549         /// we assume the invoice had the basic_mpp feature set.
1550         pub fn send_payment(&self, route: &Route, payment_hash: PaymentHash, payment_secret: &Option<PaymentSecret>) -> Result<(), PaymentSendFailure> {
1551                 if route.paths.len() < 1 {
1552                         return Err(PaymentSendFailure::ParameterError(APIError::RouteError{err: "There must be at least one path to send over"}));
1553                 }
1554                 if route.paths.len() > 10 {
1555                         // This limit is completely arbitrary - there aren't any real fundamental path-count
1556                         // limits. After we support retrying individual paths we should likely bump this, but
1557                         // for now more than 10 paths likely carries too much one-path failure.
1558                         return Err(PaymentSendFailure::ParameterError(APIError::RouteError{err: "Sending over more than 10 paths is not currently supported"}));
1559                 }
1560                 let mut total_value = 0;
1561                 let our_node_id = self.get_our_node_id();
1562                 let mut path_errs = Vec::with_capacity(route.paths.len());
1563                 'path_check: for path in route.paths.iter() {
1564                         if path.len() < 1 || path.len() > 20 {
1565                                 path_errs.push(Err(APIError::RouteError{err: "Path didn't go anywhere/had bogus size"}));
1566                                 continue 'path_check;
1567                         }
1568                         for (idx, hop) in path.iter().enumerate() {
1569                                 if idx != path.len() - 1 && hop.pubkey == our_node_id {
1570                                         path_errs.push(Err(APIError::RouteError{err: "Path went through us but wasn't a simple rebalance loop to us"}));
1571                                         continue 'path_check;
1572                                 }
1573                         }
1574                         total_value += path.last().unwrap().fee_msat;
1575                         path_errs.push(Ok(()));
1576                 }
1577                 if path_errs.iter().any(|e| e.is_err()) {
1578                         return Err(PaymentSendFailure::PathParameterError(path_errs));
1579                 }
1580
1581                 let cur_height = self.best_block.read().unwrap().height() + 1;
1582                 let mut results = Vec::new();
1583                 for path in route.paths.iter() {
1584                         results.push(self.send_payment_along_path(&path, &payment_hash, payment_secret, total_value, cur_height));
1585                 }
1586                 let mut has_ok = false;
1587                 let mut has_err = false;
1588                 for res in results.iter() {
1589                         if res.is_ok() { has_ok = true; }
1590                         if res.is_err() { has_err = true; }
1591                         if let &Err(APIError::MonitorUpdateFailed) = res {
1592                                 // MonitorUpdateFailed is inherently unsafe to retry, so we call it a
1593                                 // PartialFailure.
1594                                 has_err = true;
1595                                 has_ok = true;
1596                                 break;
1597                         }
1598                 }
1599                 if has_err && has_ok {
1600                         Err(PaymentSendFailure::PartialFailure(results))
1601                 } else if has_err {
1602                         Err(PaymentSendFailure::AllFailedRetrySafe(results.drain(..).map(|r| r.unwrap_err()).collect()))
1603                 } else {
1604                         Ok(())
1605                 }
1606         }
1607
1608         /// Handles the generation of a funding transaction, optionally (for tests) with a function
1609         /// which checks the correctness of the funding transaction given the associated channel.
1610         fn funding_transaction_generated_intern<FundingOutput: Fn(&Channel<Signer>, &Transaction) -> Result<OutPoint, APIError>>
1611                         (&self, temporary_channel_id: &[u8; 32], funding_transaction: Transaction, find_funding_output: FundingOutput) -> Result<(), APIError> {
1612                 let (chan, msg) = {
1613                         let (res, chan) = match self.channel_state.lock().unwrap().by_id.remove(temporary_channel_id) {
1614                                 Some(mut chan) => {
1615                                         let funding_txo = find_funding_output(&chan, &funding_transaction)?;
1616
1617                                         (chan.get_outbound_funding_created(funding_transaction, funding_txo, &self.logger)
1618                                                 .map_err(|e| if let ChannelError::Close(msg) = e {
1619                                                         MsgHandleErrInternal::from_finish_shutdown(msg, chan.channel_id(), chan.force_shutdown(true), None)
1620                                                 } else { unreachable!(); })
1621                                         , chan)
1622                                 },
1623                                 None => { return Err(APIError::ChannelUnavailable { err: "No such channel".to_owned() }) },
1624                         };
1625                         match handle_error!(self, res, chan.get_counterparty_node_id()) {
1626                                 Ok(funding_msg) => {
1627                                         (chan, funding_msg)
1628                                 },
1629                                 Err(_) => { return Err(APIError::ChannelUnavailable {
1630                                         err: "Error deriving keys or signing initial commitment transactions - either our RNG or our counterparty's RNG is broken or the Signer refused to sign".to_owned()
1631                                 }) },
1632                         }
1633                 };
1634
1635                 let mut channel_state = self.channel_state.lock().unwrap();
1636                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendFundingCreated {
1637                         node_id: chan.get_counterparty_node_id(),
1638                         msg,
1639                 });
1640                 match channel_state.by_id.entry(chan.channel_id()) {
1641                         hash_map::Entry::Occupied(_) => {
1642                                 panic!("Generated duplicate funding txid?");
1643                         },
1644                         hash_map::Entry::Vacant(e) => {
1645                                 e.insert(chan);
1646                         }
1647                 }
1648                 Ok(())
1649         }
1650
1651         #[cfg(test)]
1652         pub(crate) fn funding_transaction_generated_unchecked(&self, temporary_channel_id: &[u8; 32], funding_transaction: Transaction, output_index: u16) -> Result<(), APIError> {
1653                 self.funding_transaction_generated_intern(temporary_channel_id, funding_transaction, |_, tx| {
1654                         Ok(OutPoint { txid: tx.txid(), index: output_index })
1655                 })
1656         }
1657
1658         /// Call this upon creation of a funding transaction for the given channel.
1659         ///
1660         /// Returns an [`APIError::APIMisuseError`] if the funding_transaction spent non-SegWit outputs
1661         /// or if no output was found which matches the parameters in [`Event::FundingGenerationReady`].
1662         ///
1663         /// Panics if a funding transaction has already been provided for this channel.
1664         ///
1665         /// May panic if the output found in the funding transaction is duplicative with some other
1666         /// channel (note that this should be trivially prevented by using unique funding transaction
1667         /// keys per-channel).
1668         ///
1669         /// Do NOT broadcast the funding transaction yourself. When we have safely received our
1670         /// counterparty's signature the funding transaction will automatically be broadcast via the
1671         /// [`BroadcasterInterface`] provided when this `ChannelManager` was constructed.
1672         ///
1673         /// Note that this includes RBF or similar transaction replacement strategies - lightning does
1674         /// not currently support replacing a funding transaction on an existing channel. Instead,
1675         /// create a new channel with a conflicting funding transaction.
1676         pub fn funding_transaction_generated(&self, temporary_channel_id: &[u8; 32], funding_transaction: Transaction) -> Result<(), APIError> {
1677                 let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
1678
1679                 for inp in funding_transaction.input.iter() {
1680                         if inp.witness.is_empty() {
1681                                 return Err(APIError::APIMisuseError {
1682                                         err: "Funding transaction must be fully signed and spend Segwit outputs".to_owned()
1683                                 });
1684                         }
1685                 }
1686                 self.funding_transaction_generated_intern(temporary_channel_id, funding_transaction, |chan, tx| {
1687                         let mut output_index = None;
1688                         let expected_spk = chan.get_funding_redeemscript().to_v0_p2wsh();
1689                         for (idx, outp) in tx.output.iter().enumerate() {
1690                                 if outp.script_pubkey == expected_spk && outp.value == chan.get_value_satoshis() {
1691                                         if output_index.is_some() {
1692                                                 return Err(APIError::APIMisuseError {
1693                                                         err: "Multiple outputs matched the expected script and value".to_owned()
1694                                                 });
1695                                         }
1696                                         if idx > u16::max_value() as usize {
1697                                                 return Err(APIError::APIMisuseError {
1698                                                         err: "Transaction had more than 2^16 outputs, which is not supported".to_owned()
1699                                                 });
1700                                         }
1701                                         output_index = Some(idx as u16);
1702                                 }
1703                         }
1704                         if output_index.is_none() {
1705                                 return Err(APIError::APIMisuseError {
1706                                         err: "No output matched the script_pubkey and value in the FundingGenerationReady event".to_owned()
1707                                 });
1708                         }
1709                         Ok(OutPoint { txid: tx.txid(), index: output_index.unwrap() })
1710                 })
1711         }
1712
1713         fn get_announcement_sigs(&self, chan: &Channel<Signer>) -> Option<msgs::AnnouncementSignatures> {
1714                 if !chan.should_announce() {
1715                         log_trace!(self.logger, "Can't send announcement_signatures for private channel {}", log_bytes!(chan.channel_id()));
1716                         return None
1717                 }
1718
1719                 let (announcement, our_bitcoin_sig) = match chan.get_channel_announcement(self.get_our_node_id(), self.genesis_hash.clone()) {
1720                         Ok(res) => res,
1721                         Err(_) => return None, // Only in case of state precondition violations eg channel is closing
1722                 };
1723                 let msghash = hash_to_message!(&Sha256dHash::hash(&announcement.encode()[..])[..]);
1724                 let our_node_sig = self.secp_ctx.sign(&msghash, &self.our_network_key);
1725
1726                 Some(msgs::AnnouncementSignatures {
1727                         channel_id: chan.channel_id(),
1728                         short_channel_id: chan.get_short_channel_id().unwrap(),
1729                         node_signature: our_node_sig,
1730                         bitcoin_signature: our_bitcoin_sig,
1731                 })
1732         }
1733
1734         #[allow(dead_code)]
1735         // Messages of up to 64KB should never end up more than half full with addresses, as that would
1736         // be absurd. We ensure this by checking that at least 500 (our stated public contract on when
1737         // broadcast_node_announcement panics) of the maximum-length addresses would fit in a 64KB
1738         // message...
1739         const HALF_MESSAGE_IS_ADDRS: u32 = ::std::u16::MAX as u32 / (NetAddress::MAX_LEN as u32 + 1) / 2;
1740         #[deny(const_err)]
1741         #[allow(dead_code)]
1742         // ...by failing to compile if the number of addresses that would be half of a message is
1743         // smaller than 500:
1744         const STATIC_ASSERT: u32 = Self::HALF_MESSAGE_IS_ADDRS - 500;
1745
1746         /// Generates a signed node_announcement from the given arguments and creates a
1747         /// BroadcastNodeAnnouncement event. Note that such messages will be ignored unless peers have
1748         /// seen a channel_announcement from us (ie unless we have public channels open).
1749         ///
1750         /// RGB is a node "color" and alias is a printable human-readable string to describe this node
1751         /// to humans. They carry no in-protocol meaning.
1752         ///
1753         /// addresses represent the set (possibly empty) of socket addresses on which this node accepts
1754         /// incoming connections. These will be broadcast to the network, publicly tying these
1755         /// addresses together. If you wish to preserve user privacy, addresses should likely contain
1756         /// only Tor Onion addresses.
1757         ///
1758         /// Panics if addresses is absurdly large (more than 500).
1759         pub fn broadcast_node_announcement(&self, rgb: [u8; 3], alias: [u8; 32], addresses: Vec<NetAddress>) {
1760                 let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
1761
1762                 if addresses.len() > 500 {
1763                         panic!("More than half the message size was taken up by public addresses!");
1764                 }
1765
1766                 let announcement = msgs::UnsignedNodeAnnouncement {
1767                         features: NodeFeatures::known(),
1768                         timestamp: self.last_node_announcement_serial.fetch_add(1, Ordering::AcqRel) as u32,
1769                         node_id: self.get_our_node_id(),
1770                         rgb, alias, addresses,
1771                         excess_address_data: Vec::new(),
1772                         excess_data: Vec::new(),
1773                 };
1774                 let msghash = hash_to_message!(&Sha256dHash::hash(&announcement.encode()[..])[..]);
1775
1776                 let mut channel_state = self.channel_state.lock().unwrap();
1777                 channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastNodeAnnouncement {
1778                         msg: msgs::NodeAnnouncement {
1779                                 signature: self.secp_ctx.sign(&msghash, &self.our_network_key),
1780                                 contents: announcement
1781                         },
1782                 });
1783         }
1784
1785         /// Processes HTLCs which are pending waiting on random forward delay.
1786         ///
1787         /// Should only really ever be called in response to a PendingHTLCsForwardable event.
1788         /// Will likely generate further events.
1789         pub fn process_pending_htlc_forwards(&self) {
1790                 let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
1791
1792                 let mut new_events = Vec::new();
1793                 let mut failed_forwards = Vec::new();
1794                 let mut handle_errors = Vec::new();
1795                 {
1796                         let mut channel_state_lock = self.channel_state.lock().unwrap();
1797                         let channel_state = &mut *channel_state_lock;
1798
1799                         for (short_chan_id, mut pending_forwards) in channel_state.forward_htlcs.drain() {
1800                                 if short_chan_id != 0 {
1801                                         let forward_chan_id = match channel_state.short_to_id.get(&short_chan_id) {
1802                                                 Some(chan_id) => chan_id.clone(),
1803                                                 None => {
1804                                                         failed_forwards.reserve(pending_forwards.len());
1805                                                         for forward_info in pending_forwards.drain(..) {
1806                                                                 match forward_info {
1807                                                                         HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info,
1808                                                                                                    prev_funding_outpoint } => {
1809                                                                                 let htlc_source = HTLCSource::PreviousHopData(HTLCPreviousHopData {
1810                                                                                         short_channel_id: prev_short_channel_id,
1811                                                                                         outpoint: prev_funding_outpoint,
1812                                                                                         htlc_id: prev_htlc_id,
1813                                                                                         incoming_packet_shared_secret: forward_info.incoming_shared_secret,
1814                                                                                 });
1815                                                                                 failed_forwards.push((htlc_source, forward_info.payment_hash,
1816                                                                                         HTLCFailReason::Reason { failure_code: 0x4000 | 10, data: Vec::new() }
1817                                                                                 ));
1818                                                                         },
1819                                                                         HTLCForwardInfo::FailHTLC { .. } => {
1820                                                                                 // Channel went away before we could fail it. This implies
1821                                                                                 // the channel is now on chain and our counterparty is
1822                                                                                 // trying to broadcast the HTLC-Timeout, but that's their
1823                                                                                 // problem, not ours.
1824                                                                         }
1825                                                                 }
1826                                                         }
1827                                                         continue;
1828                                                 }
1829                                         };
1830                                         if let hash_map::Entry::Occupied(mut chan) = channel_state.by_id.entry(forward_chan_id) {
1831                                                 let mut add_htlc_msgs = Vec::new();
1832                                                 let mut fail_htlc_msgs = Vec::new();
1833                                                 for forward_info in pending_forwards.drain(..) {
1834                                                         match forward_info {
1835                                                                 HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info: PendingHTLCInfo {
1836                                                                                 routing: PendingHTLCRouting::Forward {
1837                                                                                         onion_packet, ..
1838                                                                                 }, incoming_shared_secret, payment_hash, amt_to_forward, outgoing_cltv_value },
1839                                                                                 prev_funding_outpoint } => {
1840                                                                         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);
1841                                                                         let htlc_source = HTLCSource::PreviousHopData(HTLCPreviousHopData {
1842                                                                                 short_channel_id: prev_short_channel_id,
1843                                                                                 outpoint: prev_funding_outpoint,
1844                                                                                 htlc_id: prev_htlc_id,
1845                                                                                 incoming_packet_shared_secret: incoming_shared_secret,
1846                                                                         });
1847                                                                         match chan.get_mut().send_htlc(amt_to_forward, payment_hash, outgoing_cltv_value, htlc_source.clone(), onion_packet) {
1848                                                                                 Err(e) => {
1849                                                                                         if let ChannelError::Ignore(msg) = e {
1850                                                                                                 log_trace!(self.logger, "Failed to forward HTLC with payment_hash {}: {}", log_bytes!(payment_hash.0), msg);
1851                                                                                         } else {
1852                                                                                                 panic!("Stated return value requirements in send_htlc() were not met");
1853                                                                                         }
1854                                                                                         let chan_update = self.get_channel_update(chan.get()).unwrap();
1855                                                                                         failed_forwards.push((htlc_source, payment_hash,
1856                                                                                                 HTLCFailReason::Reason { failure_code: 0x1000 | 7, data: chan_update.encode_with_len() }
1857                                                                                         ));
1858                                                                                         continue;
1859                                                                                 },
1860                                                                                 Ok(update_add) => {
1861                                                                                         match update_add {
1862                                                                                                 Some(msg) => { add_htlc_msgs.push(msg); },
1863                                                                                                 None => {
1864                                                                                                         // Nothing to do here...we're waiting on a remote
1865                                                                                                         // revoke_and_ack before we can add anymore HTLCs. The Channel
1866                                                                                                         // will automatically handle building the update_add_htlc and
1867                                                                                                         // commitment_signed messages when we can.
1868                                                                                                         // TODO: Do some kind of timer to set the channel as !is_live()
1869                                                                                                         // as we don't really want others relying on us relaying through
1870                                                                                                         // this channel currently :/.
1871                                                                                                 }
1872                                                                                         }
1873                                                                                 }
1874                                                                         }
1875                                                                 },
1876                                                                 HTLCForwardInfo::AddHTLC { .. } => {
1877                                                                         panic!("short_channel_id != 0 should imply any pending_forward entries are of type Forward");
1878                                                                 },
1879                                                                 HTLCForwardInfo::FailHTLC { htlc_id, err_packet } => {
1880                                                                         log_trace!(self.logger, "Failing HTLC back to channel with short id {} after delay", short_chan_id);
1881                                                                         match chan.get_mut().get_update_fail_htlc(htlc_id, err_packet) {
1882                                                                                 Err(e) => {
1883                                                                                         if let ChannelError::Ignore(msg) = e {
1884                                                                                                 log_trace!(self.logger, "Failed to fail backwards to short_id {}: {}", short_chan_id, msg);
1885                                                                                         } else {
1886                                                                                                 panic!("Stated return value requirements in get_update_fail_htlc() were not met");
1887                                                                                         }
1888                                                                                         // fail-backs are best-effort, we probably already have one
1889                                                                                         // pending, and if not that's OK, if not, the channel is on
1890                                                                                         // the chain and sending the HTLC-Timeout is their problem.
1891                                                                                         continue;
1892                                                                                 },
1893                                                                                 Ok(Some(msg)) => { fail_htlc_msgs.push(msg); },
1894                                                                                 Ok(None) => {
1895                                                                                         // Nothing to do here...we're waiting on a remote
1896                                                                                         // revoke_and_ack before we can update the commitment
1897                                                                                         // transaction. The Channel will automatically handle
1898                                                                                         // building the update_fail_htlc and commitment_signed
1899                                                                                         // messages when we can.
1900                                                                                         // We don't need any kind of timer here as they should fail
1901                                                                                         // the channel onto the chain if they can't get our
1902                                                                                         // update_fail_htlc in time, it's not our problem.
1903                                                                                 }
1904                                                                         }
1905                                                                 },
1906                                                         }
1907                                                 }
1908
1909                                                 if !add_htlc_msgs.is_empty() || !fail_htlc_msgs.is_empty() {
1910                                                         let (commitment_msg, monitor_update) = match chan.get_mut().send_commitment(&self.logger) {
1911                                                                 Ok(res) => res,
1912                                                                 Err(e) => {
1913                                                                         // We surely failed send_commitment due to bad keys, in that case
1914                                                                         // close channel and then send error message to peer.
1915                                                                         let counterparty_node_id = chan.get().get_counterparty_node_id();
1916                                                                         let err: Result<(), _>  = match e {
1917                                                                                 ChannelError::Ignore(_) => {
1918                                                                                         panic!("Stated return value requirements in send_commitment() were not met");
1919                                                                                 },
1920                                                                                 ChannelError::Close(msg) => {
1921                                                                                         log_trace!(self.logger, "Closing channel {} due to Close-required error: {}", log_bytes!(chan.key()[..]), msg);
1922                                                                                         let (channel_id, mut channel) = chan.remove_entry();
1923                                                                                         if let Some(short_id) = channel.get_short_channel_id() {
1924                                                                                                 channel_state.short_to_id.remove(&short_id);
1925                                                                                         }
1926                                                                                         Err(MsgHandleErrInternal::from_finish_shutdown(msg, channel_id, channel.force_shutdown(true), self.get_channel_update(&channel).ok()))
1927                                                                                 },
1928                                                                                 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"); }
1929                                                                         };
1930                                                                         handle_errors.push((counterparty_node_id, err));
1931                                                                         continue;
1932                                                                 }
1933                                                         };
1934                                                         if let Err(e) = self.chain_monitor.update_channel(chan.get().get_funding_txo().unwrap(), monitor_update) {
1935                                                                 handle_errors.push((chan.get().get_counterparty_node_id(), handle_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::CommitmentFirst, false, true)));
1936                                                                 continue;
1937                                                         }
1938                                                         channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
1939                                                                 node_id: chan.get().get_counterparty_node_id(),
1940                                                                 updates: msgs::CommitmentUpdate {
1941                                                                         update_add_htlcs: add_htlc_msgs,
1942                                                                         update_fulfill_htlcs: Vec::new(),
1943                                                                         update_fail_htlcs: fail_htlc_msgs,
1944                                                                         update_fail_malformed_htlcs: Vec::new(),
1945                                                                         update_fee: None,
1946                                                                         commitment_signed: commitment_msg,
1947                                                                 },
1948                                                         });
1949                                                 }
1950                                         } else {
1951                                                 unreachable!();
1952                                         }
1953                                 } else {
1954                                         for forward_info in pending_forwards.drain(..) {
1955                                                 match forward_info {
1956                                                         HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info: PendingHTLCInfo {
1957                                                                         routing: PendingHTLCRouting::Receive { payment_data, incoming_cltv_expiry },
1958                                                                         incoming_shared_secret, payment_hash, amt_to_forward, .. },
1959                                                                         prev_funding_outpoint } => {
1960                                                                 let claimable_htlc = ClaimableHTLC {
1961                                                                         prev_hop: HTLCPreviousHopData {
1962                                                                                 short_channel_id: prev_short_channel_id,
1963                                                                                 outpoint: prev_funding_outpoint,
1964                                                                                 htlc_id: prev_htlc_id,
1965                                                                                 incoming_packet_shared_secret: incoming_shared_secret,
1966                                                                         },
1967                                                                         value: amt_to_forward,
1968                                                                         payment_data: payment_data.clone(),
1969                                                                         cltv_expiry: incoming_cltv_expiry,
1970                                                                 };
1971
1972                                                                 macro_rules! fail_htlc {
1973                                                                         ($htlc: expr) => {
1974                                                                                 let mut htlc_msat_height_data = byte_utils::be64_to_array($htlc.value).to_vec();
1975                                                                                 htlc_msat_height_data.extend_from_slice(
1976                                                                                         &byte_utils::be32_to_array(self.best_block.read().unwrap().height()),
1977                                                                                 );
1978                                                                                 failed_forwards.push((HTLCSource::PreviousHopData(HTLCPreviousHopData {
1979                                                                                                 short_channel_id: $htlc.prev_hop.short_channel_id,
1980                                                                                                 outpoint: prev_funding_outpoint,
1981                                                                                                 htlc_id: $htlc.prev_hop.htlc_id,
1982                                                                                                 incoming_packet_shared_secret: $htlc.prev_hop.incoming_packet_shared_secret,
1983                                                                                         }), payment_hash,
1984                                                                                         HTLCFailReason::Reason { failure_code: 0x4000 | 15, data: htlc_msat_height_data }
1985                                                                                 ));
1986                                                                         }
1987                                                                 }
1988
1989                                                                 // Check that the payment hash and secret are known. Note that we
1990                                                                 // MUST take care to handle the "unknown payment hash" and
1991                                                                 // "incorrect payment secret" cases here identically or we'd expose
1992                                                                 // that we are the ultimate recipient of the given payment hash.
1993                                                                 // Further, we must not expose whether we have any other HTLCs
1994                                                                 // associated with the same payment_hash pending or not.
1995                                                                 let mut payment_secrets = self.pending_inbound_payments.lock().unwrap();
1996                                                                 match payment_secrets.entry(payment_hash) {
1997                                                                         hash_map::Entry::Vacant(_) => {
1998                                                                                 log_trace!(self.logger, "Failing new HTLC with payment_hash {} as we didn't have a corresponding inbound payment.", log_bytes!(payment_hash.0));
1999                                                                                 fail_htlc!(claimable_htlc);
2000                                                                         },
2001                                                                         hash_map::Entry::Occupied(inbound_payment) => {
2002                                                                                 if inbound_payment.get().payment_secret != payment_data.payment_secret {
2003                                                                                         log_trace!(self.logger, "Failing new HTLC with payment_hash {} as it didn't match our expected payment secret.", log_bytes!(payment_hash.0));
2004                                                                                         fail_htlc!(claimable_htlc);
2005                                                                                 } else if inbound_payment.get().min_value_msat.is_some() && payment_data.total_msat < inbound_payment.get().min_value_msat.unwrap() {
2006                                                                                         log_trace!(self.logger, "Failing new HTLC with payment_hash {} as it didn't match our minimum value (had {}, needed {}).",
2007                                                                                                 log_bytes!(payment_hash.0), payment_data.total_msat, inbound_payment.get().min_value_msat.unwrap());
2008                                                                                         fail_htlc!(claimable_htlc);
2009                                                                                 } else {
2010                                                                                         let mut total_value = 0;
2011                                                                                         let htlcs = channel_state.claimable_htlcs.entry(payment_hash)
2012                                                                                                 .or_insert(Vec::new());
2013                                                                                         htlcs.push(claimable_htlc);
2014                                                                                         for htlc in htlcs.iter() {
2015                                                                                                 total_value += htlc.value;
2016                                                                                                 if htlc.payment_data.total_msat != payment_data.total_msat {
2017                                                                                                         log_trace!(self.logger, "Failing HTLCs with payment_hash {} as the HTLCs had inconsistent total values (eg {} and {})",
2018                                                                                                                 log_bytes!(payment_hash.0), payment_data.total_msat, htlc.payment_data.total_msat);
2019                                                                                                         total_value = msgs::MAX_VALUE_MSAT;
2020                                                                                                 }
2021                                                                                                 if total_value >= msgs::MAX_VALUE_MSAT { break; }
2022                                                                                         }
2023                                                                                         if total_value >= msgs::MAX_VALUE_MSAT || total_value > payment_data.total_msat {
2024                                                                                                 log_trace!(self.logger, "Failing HTLCs with payment_hash {} as the total value {} ran over expected value {} (or HTLCs were inconsistent)",
2025                                                                                                         log_bytes!(payment_hash.0), total_value, payment_data.total_msat);
2026                                                                                                 for htlc in htlcs.iter() {
2027                                                                                                         fail_htlc!(htlc);
2028                                                                                                 }
2029                                                                                         } else if total_value == payment_data.total_msat {
2030                                                                                                 new_events.push(events::Event::PaymentReceived {
2031                                                                                                         payment_hash,
2032                                                                                                         payment_preimage: inbound_payment.get().payment_preimage,
2033                                                                                                         payment_secret: payment_data.payment_secret,
2034                                                                                                         amt: total_value,
2035                                                                                                         user_payment_id: inbound_payment.get().user_payment_id,
2036                                                                                                 });
2037                                                                                                 // Only ever generate at most one PaymentReceived
2038                                                                                                 // per registered payment_hash, even if it isn't
2039                                                                                                 // claimed.
2040                                                                                                 inbound_payment.remove_entry();
2041                                                                                         } else {
2042                                                                                                 // Nothing to do - we haven't reached the total
2043                                                                                                 // payment value yet, wait until we receive more
2044                                                                                                 // MPP parts.
2045                                                                                         }
2046                                                                                 }
2047                                                                         },
2048                                                                 };
2049                                                         },
2050                                                         HTLCForwardInfo::AddHTLC { .. } => {
2051                                                                 panic!("short_channel_id == 0 should imply any pending_forward entries are of type Receive");
2052                                                         },
2053                                                         HTLCForwardInfo::FailHTLC { .. } => {
2054                                                                 panic!("Got pending fail of our own HTLC");
2055                                                         }
2056                                                 }
2057                                         }
2058                                 }
2059                         }
2060                 }
2061
2062                 for (htlc_source, payment_hash, failure_reason) in failed_forwards.drain(..) {
2063                         self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), htlc_source, &payment_hash, failure_reason);
2064                 }
2065
2066                 for (counterparty_node_id, err) in handle_errors.drain(..) {
2067                         let _ = handle_error!(self, err, counterparty_node_id);
2068                 }
2069
2070                 if new_events.is_empty() { return }
2071                 let mut events = self.pending_events.lock().unwrap();
2072                 events.append(&mut new_events);
2073         }
2074
2075         /// Free the background events, generally called from timer_tick_occurred.
2076         ///
2077         /// Exposed for testing to allow us to process events quickly without generating accidental
2078         /// BroadcastChannelUpdate events in timer_tick_occurred.
2079         ///
2080         /// Expects the caller to have a total_consistency_lock read lock.
2081         fn process_background_events(&self) {
2082                 let mut background_events = Vec::new();
2083                 mem::swap(&mut *self.pending_background_events.lock().unwrap(), &mut background_events);
2084                 for event in background_events.drain(..) {
2085                         match event {
2086                                 BackgroundEvent::ClosingMonitorUpdate((funding_txo, update)) => {
2087                                         // The channel has already been closed, so no use bothering to care about the
2088                                         // monitor updating completing.
2089                                         let _ = self.chain_monitor.update_channel(funding_txo, update);
2090                                 },
2091                         }
2092                 }
2093         }
2094
2095         #[cfg(any(test, feature = "_test_utils"))]
2096         pub(crate) fn test_process_background_events(&self) {
2097                 self.process_background_events();
2098         }
2099
2100         /// If a peer is disconnected we mark any channels with that peer as 'disabled'.
2101         /// After some time, if channels are still disabled we need to broadcast a ChannelUpdate
2102         /// to inform the network about the uselessness of these channels.
2103         ///
2104         /// This method handles all the details, and must be called roughly once per minute.
2105         ///
2106         /// Note that in some rare cases this may generate a `chain::Watch::update_channel` call.
2107         pub fn timer_tick_occurred(&self) {
2108                 let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
2109                 self.process_background_events();
2110
2111                 let mut channel_state_lock = self.channel_state.lock().unwrap();
2112                 let channel_state = &mut *channel_state_lock;
2113                 for (_, chan) in channel_state.by_id.iter_mut() {
2114                         if chan.is_disabled_staged() && !chan.is_live() {
2115                                 if let Ok(update) = self.get_channel_update(&chan) {
2116                                         channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
2117                                                 msg: update
2118                                         });
2119                                 }
2120                                 chan.to_fresh();
2121                         } else if chan.is_disabled_staged() && chan.is_live() {
2122                                 chan.to_fresh();
2123                         } else if chan.is_disabled_marked() {
2124                                 chan.to_disabled_staged();
2125                         }
2126                 }
2127         }
2128
2129         /// Indicates that the preimage for payment_hash is unknown or the received amount is incorrect
2130         /// after a PaymentReceived event, failing the HTLC back to its origin and freeing resources
2131         /// along the path (including in our own channel on which we received it).
2132         /// Returns false if no payment was found to fail backwards, true if the process of failing the
2133         /// HTLC backwards has been started.
2134         pub fn fail_htlc_backwards(&self, payment_hash: &PaymentHash) -> bool {
2135                 let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
2136
2137                 let mut channel_state = Some(self.channel_state.lock().unwrap());
2138                 let removed_source = channel_state.as_mut().unwrap().claimable_htlcs.remove(payment_hash);
2139                 if let Some(mut sources) = removed_source {
2140                         for htlc in sources.drain(..) {
2141                                 if channel_state.is_none() { channel_state = Some(self.channel_state.lock().unwrap()); }
2142                                 let mut htlc_msat_height_data = byte_utils::be64_to_array(htlc.value).to_vec();
2143                                 htlc_msat_height_data.extend_from_slice(&byte_utils::be32_to_array(
2144                                                 self.best_block.read().unwrap().height()));
2145                                 self.fail_htlc_backwards_internal(channel_state.take().unwrap(),
2146                                                 HTLCSource::PreviousHopData(htlc.prev_hop), payment_hash,
2147                                                 HTLCFailReason::Reason { failure_code: 0x4000 | 15, data: htlc_msat_height_data });
2148                         }
2149                         true
2150                 } else { false }
2151         }
2152
2153         // Fail a list of HTLCs that were just freed from the holding cell. The HTLCs need to be
2154         // failed backwards or, if they were one of our outgoing HTLCs, then their failure needs to
2155         // be surfaced to the user.
2156         fn fail_holding_cell_htlcs(&self, mut htlcs_to_fail: Vec<(HTLCSource, PaymentHash)>, channel_id: [u8; 32]) {
2157                 for (htlc_src, payment_hash) in htlcs_to_fail.drain(..) {
2158                         match htlc_src {
2159                                 HTLCSource::PreviousHopData(HTLCPreviousHopData { .. }) => {
2160                                         let (failure_code, onion_failure_data) =
2161                                                 match self.channel_state.lock().unwrap().by_id.entry(channel_id) {
2162                                                         hash_map::Entry::Occupied(chan_entry) => {
2163                                                                 if let Ok(upd) = self.get_channel_update(&chan_entry.get()) {
2164                                                                         (0x1000|7, upd.encode_with_len())
2165                                                                 } else {
2166                                                                         (0x4000|10, Vec::new())
2167                                                                 }
2168                                                         },
2169                                                         hash_map::Entry::Vacant(_) => (0x4000|10, Vec::new())
2170                                                 };
2171                                         let channel_state = self.channel_state.lock().unwrap();
2172                                         self.fail_htlc_backwards_internal(channel_state,
2173                                                 htlc_src, &payment_hash, HTLCFailReason::Reason { failure_code, data: onion_failure_data});
2174                                 },
2175                                 HTLCSource::OutboundRoute { .. } => {
2176                                         self.pending_events.lock().unwrap().push(
2177                                                 events::Event::PaymentFailed {
2178                                                         payment_hash,
2179                                                         rejected_by_dest: false,
2180 #[cfg(test)]
2181                                                         error_code: None,
2182 #[cfg(test)]
2183                                                         error_data: None,
2184                                                 }
2185                                         )
2186                                 },
2187                         };
2188                 }
2189         }
2190
2191         /// Fails an HTLC backwards to the sender of it to us.
2192         /// Note that while we take a channel_state lock as input, we do *not* assume consistency here.
2193         /// There are several callsites that do stupid things like loop over a list of payment_hashes
2194         /// to fail and take the channel_state lock for each iteration (as we take ownership and may
2195         /// drop it). In other words, no assumptions are made that entries in claimable_htlcs point to
2196         /// still-available channels.
2197         fn fail_htlc_backwards_internal(&self, mut channel_state_lock: MutexGuard<ChannelHolder<Signer>>, source: HTLCSource, payment_hash: &PaymentHash, onion_error: HTLCFailReason) {
2198                 //TODO: There is a timing attack here where if a node fails an HTLC back to us they can
2199                 //identify whether we sent it or not based on the (I presume) very different runtime
2200                 //between the branches here. We should make this async and move it into the forward HTLCs
2201                 //timer handling.
2202
2203                 // Note that we MUST NOT end up calling methods on self.chain_monitor here - we're called
2204                 // from block_connected which may run during initialization prior to the chain_monitor
2205                 // being fully configured. See the docs for `ChannelManagerReadArgs` for more.
2206                 match source {
2207                         HTLCSource::OutboundRoute { ref path, .. } => {
2208                                 log_trace!(self.logger, "Failing outbound payment HTLC with payment_hash {}", log_bytes!(payment_hash.0));
2209                                 mem::drop(channel_state_lock);
2210                                 match &onion_error {
2211                                         &HTLCFailReason::LightningError { ref err } => {
2212 #[cfg(test)]
2213                                                 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());
2214 #[cfg(not(test))]
2215                                                 let (channel_update, payment_retryable, _, _) = onion_utils::process_onion_failure(&self.secp_ctx, &self.logger, &source, err.data.clone());
2216                                                 // TODO: If we decided to blame ourselves (or one of our channels) in
2217                                                 // process_onion_failure we should close that channel as it implies our
2218                                                 // next-hop is needlessly blaming us!
2219                                                 if let Some(update) = channel_update {
2220                                                         self.channel_state.lock().unwrap().pending_msg_events.push(
2221                                                                 events::MessageSendEvent::PaymentFailureNetworkUpdate {
2222                                                                         update,
2223                                                                 }
2224                                                         );
2225                                                 }
2226                                                 self.pending_events.lock().unwrap().push(
2227                                                         events::Event::PaymentFailed {
2228                                                                 payment_hash: payment_hash.clone(),
2229                                                                 rejected_by_dest: !payment_retryable,
2230 #[cfg(test)]
2231                                                                 error_code: onion_error_code,
2232 #[cfg(test)]
2233                                                                 error_data: onion_error_data
2234                                                         }
2235                                                 );
2236                                         },
2237                                         &HTLCFailReason::Reason {
2238 #[cfg(test)]
2239                                                         ref failure_code,
2240 #[cfg(test)]
2241                                                         ref data,
2242                                                         .. } => {
2243                                                 // we get a fail_malformed_htlc from the first hop
2244                                                 // TODO: We'd like to generate a PaymentFailureNetworkUpdate for temporary
2245                                                 // failures here, but that would be insufficient as get_route
2246                                                 // generally ignores its view of our own channels as we provide them via
2247                                                 // ChannelDetails.
2248                                                 // TODO: For non-temporary failures, we really should be closing the
2249                                                 // channel here as we apparently can't relay through them anyway.
2250                                                 self.pending_events.lock().unwrap().push(
2251                                                         events::Event::PaymentFailed {
2252                                                                 payment_hash: payment_hash.clone(),
2253                                                                 rejected_by_dest: path.len() == 1,
2254 #[cfg(test)]
2255                                                                 error_code: Some(*failure_code),
2256 #[cfg(test)]
2257                                                                 error_data: Some(data.clone()),
2258                                                         }
2259                                                 );
2260                                         }
2261                                 }
2262                         },
2263                         HTLCSource::PreviousHopData(HTLCPreviousHopData { short_channel_id, htlc_id, incoming_packet_shared_secret, .. }) => {
2264                                 let err_packet = match onion_error {
2265                                         HTLCFailReason::Reason { failure_code, data } => {
2266                                                 log_trace!(self.logger, "Failing HTLC with payment_hash {} backwards from us with code {}", log_bytes!(payment_hash.0), failure_code);
2267                                                 let packet = onion_utils::build_failure_packet(&incoming_packet_shared_secret, failure_code, &data[..]).encode();
2268                                                 onion_utils::encrypt_failure_packet(&incoming_packet_shared_secret, &packet)
2269                                         },
2270                                         HTLCFailReason::LightningError { err } => {
2271                                                 log_trace!(self.logger, "Failing HTLC with payment_hash {} backwards with pre-built LightningError", log_bytes!(payment_hash.0));
2272                                                 onion_utils::encrypt_failure_packet(&incoming_packet_shared_secret, &err.data)
2273                                         }
2274                                 };
2275
2276                                 let mut forward_event = None;
2277                                 if channel_state_lock.forward_htlcs.is_empty() {
2278                                         forward_event = Some(Duration::from_millis(MIN_HTLC_RELAY_HOLDING_CELL_MILLIS));
2279                                 }
2280                                 match channel_state_lock.forward_htlcs.entry(short_channel_id) {
2281                                         hash_map::Entry::Occupied(mut entry) => {
2282                                                 entry.get_mut().push(HTLCForwardInfo::FailHTLC { htlc_id, err_packet });
2283                                         },
2284                                         hash_map::Entry::Vacant(entry) => {
2285                                                 entry.insert(vec!(HTLCForwardInfo::FailHTLC { htlc_id, err_packet }));
2286                                         }
2287                                 }
2288                                 mem::drop(channel_state_lock);
2289                                 if let Some(time) = forward_event {
2290                                         let mut pending_events = self.pending_events.lock().unwrap();
2291                                         pending_events.push(events::Event::PendingHTLCsForwardable {
2292                                                 time_forwardable: time
2293                                         });
2294                                 }
2295                         },
2296                 }
2297         }
2298
2299         /// Provides a payment preimage in response to a PaymentReceived event, returning true and
2300         /// generating message events for the net layer to claim the payment, if possible. Thus, you
2301         /// should probably kick the net layer to go send messages if this returns true!
2302         ///
2303         /// Note that if you did not set an `amount_msat` when calling [`create_inbound_payment`] or
2304         /// [`create_inbound_payment_for_hash`] you must check that the amount in the `PaymentReceived`
2305         /// event matches your expectation. If you fail to do so and call this method, you may provide
2306         /// the sender "proof-of-payment" when they did not fulfill the full expected payment.
2307         ///
2308         /// May panic if called except in response to a PaymentReceived event.
2309         ///
2310         /// [`create_inbound_payment`]: Self::create_inbound_payment
2311         /// [`create_inbound_payment_for_hash`]: Self::create_inbound_payment_for_hash
2312         pub fn claim_funds(&self, payment_preimage: PaymentPreimage) -> bool {
2313                 let payment_hash = PaymentHash(Sha256::hash(&payment_preimage.0).into_inner());
2314
2315                 let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
2316
2317                 let mut channel_state = Some(self.channel_state.lock().unwrap());
2318                 let removed_source = channel_state.as_mut().unwrap().claimable_htlcs.remove(&payment_hash);
2319                 if let Some(mut sources) = removed_source {
2320                         assert!(!sources.is_empty());
2321
2322                         // If we are claiming an MPP payment, we have to take special care to ensure that each
2323                         // channel exists before claiming all of the payments (inside one lock).
2324                         // Note that channel existance is sufficient as we should always get a monitor update
2325                         // which will take care of the real HTLC claim enforcement.
2326                         //
2327                         // If we find an HTLC which we would need to claim but for which we do not have a
2328                         // channel, we will fail all parts of the MPP payment. While we could wait and see if
2329                         // the sender retries the already-failed path(s), it should be a pretty rare case where
2330                         // we got all the HTLCs and then a channel closed while we were waiting for the user to
2331                         // provide the preimage, so worrying too much about the optimal handling isn't worth
2332                         // it.
2333                         let mut valid_mpp = true;
2334                         for htlc in sources.iter() {
2335                                 if let None = channel_state.as_ref().unwrap().short_to_id.get(&htlc.prev_hop.short_channel_id) {
2336                                         valid_mpp = false;
2337                                         break;
2338                                 }
2339                         }
2340
2341                         let mut errs = Vec::new();
2342                         let mut claimed_any_htlcs = false;
2343                         for htlc in sources.drain(..) {
2344                                 if !valid_mpp {
2345                                         if channel_state.is_none() { channel_state = Some(self.channel_state.lock().unwrap()); }
2346                                         let mut htlc_msat_height_data = byte_utils::be64_to_array(htlc.value).to_vec();
2347                                         htlc_msat_height_data.extend_from_slice(&byte_utils::be32_to_array(
2348                                                         self.best_block.read().unwrap().height()));
2349                                         self.fail_htlc_backwards_internal(channel_state.take().unwrap(),
2350                                                                          HTLCSource::PreviousHopData(htlc.prev_hop), &payment_hash,
2351                                                                          HTLCFailReason::Reason { failure_code: 0x4000|15, data: htlc_msat_height_data });
2352                                 } else {
2353                                         match self.claim_funds_from_hop(channel_state.as_mut().unwrap(), htlc.prev_hop, payment_preimage) {
2354                                                 Err(Some(e)) => {
2355                                                         if let msgs::ErrorAction::IgnoreError = e.1.err.action {
2356                                                                 // We got a temporary failure updating monitor, but will claim the
2357                                                                 // HTLC when the monitor updating is restored (or on chain).
2358                                                                 log_error!(self.logger, "Temporary failure claiming HTLC, treating as success: {}", e.1.err.err);
2359                                                                 claimed_any_htlcs = true;
2360                                                         } else { errs.push(e); }
2361                                                 },
2362                                                 Err(None) => unreachable!("We already checked for channel existence, we can't fail here!"),
2363                                                 Ok(()) => claimed_any_htlcs = true,
2364                                         }
2365                                 }
2366                         }
2367
2368                         // Now that we've done the entire above loop in one lock, we can handle any errors
2369                         // which were generated.
2370                         channel_state.take();
2371
2372                         for (counterparty_node_id, err) in errs.drain(..) {
2373                                 let res: Result<(), _> = Err(err);
2374                                 let _ = handle_error!(self, res, counterparty_node_id);
2375                         }
2376
2377                         claimed_any_htlcs
2378                 } else { false }
2379         }
2380
2381         fn claim_funds_from_hop(&self, channel_state_lock: &mut MutexGuard<ChannelHolder<Signer>>, prev_hop: HTLCPreviousHopData, payment_preimage: PaymentPreimage) -> Result<(), Option<(PublicKey, MsgHandleErrInternal)>> {
2382                 //TODO: Delay the claimed_funds relaying just like we do outbound relay!
2383                 let channel_state = &mut **channel_state_lock;
2384                 let chan_id = match channel_state.short_to_id.get(&prev_hop.short_channel_id) {
2385                         Some(chan_id) => chan_id.clone(),
2386                         None => {
2387                                 return Err(None)
2388                         }
2389                 };
2390
2391                 if let hash_map::Entry::Occupied(mut chan) = channel_state.by_id.entry(chan_id) {
2392                         let was_frozen_for_monitor = chan.get().is_awaiting_monitor_update();
2393                         match chan.get_mut().get_update_fulfill_htlc_and_commit(prev_hop.htlc_id, payment_preimage, &self.logger) {
2394                                 Ok((msgs, monitor_option)) => {
2395                                         if let Some(monitor_update) = monitor_option {
2396                                                 if let Err(e) = self.chain_monitor.update_channel(chan.get().get_funding_txo().unwrap(), monitor_update) {
2397                                                         if was_frozen_for_monitor {
2398                                                                 assert!(msgs.is_none());
2399                                                         } else {
2400                                                                 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())));
2401                                                         }
2402                                                 }
2403                                         }
2404                                         if let Some((msg, commitment_signed)) = msgs {
2405                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
2406                                                         node_id: chan.get().get_counterparty_node_id(),
2407                                                         updates: msgs::CommitmentUpdate {
2408                                                                 update_add_htlcs: Vec::new(),
2409                                                                 update_fulfill_htlcs: vec![msg],
2410                                                                 update_fail_htlcs: Vec::new(),
2411                                                                 update_fail_malformed_htlcs: Vec::new(),
2412                                                                 update_fee: None,
2413                                                                 commitment_signed,
2414                                                         }
2415                                                 });
2416                                         }
2417                                         return Ok(())
2418                                 },
2419                                 Err(e) => {
2420                                         // TODO: Do something with e?
2421                                         // This should only occur if we are claiming an HTLC at the same time as the
2422                                         // HTLC is being failed (eg because a block is being connected and this caused
2423                                         // an HTLC to time out). This should, of course, only occur if the user is the
2424                                         // one doing the claiming (as it being a part of a peer claim would imply we're
2425                                         // about to lose funds) and only if the lock in claim_funds was dropped as a
2426                                         // previous HTLC was failed (thus not for an MPP payment).
2427                                         debug_assert!(false, "This shouldn't be reachable except in absurdly rare cases between monitor updates and HTLC timeouts: {:?}", e);
2428                                         return Err(None)
2429                                 },
2430                         }
2431                 } else { unreachable!(); }
2432         }
2433
2434         fn claim_funds_internal(&self, mut channel_state_lock: MutexGuard<ChannelHolder<Signer>>, source: HTLCSource, payment_preimage: PaymentPreimage) {
2435                 match source {
2436                         HTLCSource::OutboundRoute { .. } => {
2437                                 mem::drop(channel_state_lock);
2438                                 let mut pending_events = self.pending_events.lock().unwrap();
2439                                 pending_events.push(events::Event::PaymentSent {
2440                                         payment_preimage
2441                                 });
2442                         },
2443                         HTLCSource::PreviousHopData(hop_data) => {
2444                                 let prev_outpoint = hop_data.outpoint;
2445                                 if let Err((counterparty_node_id, err)) = match self.claim_funds_from_hop(&mut channel_state_lock, hop_data, payment_preimage) {
2446                                         Ok(()) => Ok(()),
2447                                         Err(None) => {
2448                                                 let preimage_update = ChannelMonitorUpdate {
2449                                                         update_id: CLOSED_CHANNEL_UPDATE_ID,
2450                                                         updates: vec![ChannelMonitorUpdateStep::PaymentPreimage {
2451                                                                 payment_preimage: payment_preimage.clone(),
2452                                                         }],
2453                                                 };
2454                                                 // We update the ChannelMonitor on the backward link, after
2455                                                 // receiving an offchain preimage event from the forward link (the
2456                                                 // event being update_fulfill_htlc).
2457                                                 if let Err(e) = self.chain_monitor.update_channel(prev_outpoint, preimage_update) {
2458                                                         log_error!(self.logger, "Critical error: failed to update channel monitor with preimage {:?}: {:?}",
2459                                                                    payment_preimage, e);
2460                                                 }
2461                                                 Ok(())
2462                                         },
2463                                         Err(Some(res)) => Err(res),
2464                                 } {
2465                                         mem::drop(channel_state_lock);
2466                                         let res: Result<(), _> = Err(err);
2467                                         let _ = handle_error!(self, res, counterparty_node_id);
2468                                 }
2469                         },
2470                 }
2471         }
2472
2473         /// Gets the node_id held by this ChannelManager
2474         pub fn get_our_node_id(&self) -> PublicKey {
2475                 self.our_network_pubkey.clone()
2476         }
2477
2478         /// Restores a single, given channel to normal operation after a
2479         /// ChannelMonitorUpdateErr::TemporaryFailure was returned from a channel monitor update
2480         /// operation.
2481         ///
2482         /// All ChannelMonitor updates up to and including highest_applied_update_id must have been
2483         /// fully committed in every copy of the given channels' ChannelMonitors.
2484         ///
2485         /// Note that there is no effect to calling with a highest_applied_update_id other than the
2486         /// current latest ChannelMonitorUpdate and one call to this function after multiple
2487         /// ChannelMonitorUpdateErr::TemporaryFailures is fine. The highest_applied_update_id field
2488         /// exists largely only to prevent races between this and concurrent update_monitor calls.
2489         ///
2490         /// Thus, the anticipated use is, at a high level:
2491         ///  1) You register a chain::Watch with this ChannelManager,
2492         ///  2) it stores each update to disk, and begins updating any remote (eg watchtower) copies of
2493         ///     said ChannelMonitors as it can, returning ChannelMonitorUpdateErr::TemporaryFailures
2494         ///     any time it cannot do so instantly,
2495         ///  3) update(s) are applied to each remote copy of a ChannelMonitor,
2496         ///  4) once all remote copies are updated, you call this function with the update_id that
2497         ///     completed, and once it is the latest the Channel will be re-enabled.
2498         pub fn channel_monitor_updated(&self, funding_txo: &OutPoint, highest_applied_update_id: u64) {
2499                 let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
2500
2501                 let mut close_results = Vec::new();
2502                 let mut htlc_forwards = Vec::new();
2503                 let mut htlc_failures = Vec::new();
2504                 let mut pending_events = Vec::new();
2505
2506                 {
2507                         let mut channel_lock = self.channel_state.lock().unwrap();
2508                         let channel_state = &mut *channel_lock;
2509                         let short_to_id = &mut channel_state.short_to_id;
2510                         let pending_msg_events = &mut channel_state.pending_msg_events;
2511                         let channel = match channel_state.by_id.get_mut(&funding_txo.to_channel_id()) {
2512                                 Some(chan) => chan,
2513                                 None => return,
2514                         };
2515                         if !channel.is_awaiting_monitor_update() || channel.get_latest_monitor_update_id() != highest_applied_update_id {
2516                                 return;
2517                         }
2518
2519                         let (raa, commitment_update, order, pending_forwards, mut pending_failures, funding_broadcastable, funding_locked) = channel.monitor_updating_restored(&self.logger);
2520                         if !pending_forwards.is_empty() {
2521                                 htlc_forwards.push((channel.get_short_channel_id().expect("We can't have pending forwards before funding confirmation"), funding_txo.clone(), pending_forwards));
2522                         }
2523                         htlc_failures.append(&mut pending_failures);
2524
2525                         macro_rules! handle_cs { () => {
2526                                 if let Some(update) = commitment_update {
2527                                         pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
2528                                                 node_id: channel.get_counterparty_node_id(),
2529                                                 updates: update,
2530                                         });
2531                                 }
2532                         } }
2533                         macro_rules! handle_raa { () => {
2534                                 if let Some(revoke_and_ack) = raa {
2535                                         pending_msg_events.push(events::MessageSendEvent::SendRevokeAndACK {
2536                                                 node_id: channel.get_counterparty_node_id(),
2537                                                 msg: revoke_and_ack,
2538                                         });
2539                                 }
2540                         } }
2541                         match order {
2542                                 RAACommitmentOrder::CommitmentFirst => {
2543                                         handle_cs!();
2544                                         handle_raa!();
2545                                 },
2546                                 RAACommitmentOrder::RevokeAndACKFirst => {
2547                                         handle_raa!();
2548                                         handle_cs!();
2549                                 },
2550                         }
2551                         if let Some(tx) = funding_broadcastable {
2552                                 self.tx_broadcaster.broadcast_transaction(&tx);
2553                         }
2554                         if let Some(msg) = funding_locked {
2555                                 pending_msg_events.push(events::MessageSendEvent::SendFundingLocked {
2556                                         node_id: channel.get_counterparty_node_id(),
2557                                         msg,
2558                                 });
2559                                 if let Some(announcement_sigs) = self.get_announcement_sigs(channel) {
2560                                         pending_msg_events.push(events::MessageSendEvent::SendAnnouncementSignatures {
2561                                                 node_id: channel.get_counterparty_node_id(),
2562                                                 msg: announcement_sigs,
2563                                         });
2564                                 }
2565                                 short_to_id.insert(channel.get_short_channel_id().unwrap(), channel.channel_id());
2566                         }
2567                 }
2568
2569                 self.pending_events.lock().unwrap().append(&mut pending_events);
2570
2571                 for failure in htlc_failures.drain(..) {
2572                         self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), failure.0, &failure.1, failure.2);
2573                 }
2574                 self.forward_htlcs(&mut htlc_forwards[..]);
2575
2576                 for res in close_results.drain(..) {
2577                         self.finish_force_close_channel(res);
2578                 }
2579         }
2580
2581         fn internal_open_channel(&self, counterparty_node_id: &PublicKey, their_features: InitFeatures, msg: &msgs::OpenChannel) -> Result<(), MsgHandleErrInternal> {
2582                 if msg.chain_hash != self.genesis_hash {
2583                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Unknown genesis block hash".to_owned(), msg.temporary_channel_id.clone()));
2584                 }
2585
2586                 let channel = Channel::new_from_req(&self.fee_estimator, &self.keys_manager, counterparty_node_id.clone(), their_features, msg, 0, &self.default_configuration)
2587                         .map_err(|e| MsgHandleErrInternal::from_chan_no_close(e, msg.temporary_channel_id))?;
2588                 let mut channel_state_lock = self.channel_state.lock().unwrap();
2589                 let channel_state = &mut *channel_state_lock;
2590                 match channel_state.by_id.entry(channel.channel_id()) {
2591                         hash_map::Entry::Occupied(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("temporary_channel_id collision!".to_owned(), msg.temporary_channel_id.clone())),
2592                         hash_map::Entry::Vacant(entry) => {
2593                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendAcceptChannel {
2594                                         node_id: counterparty_node_id.clone(),
2595                                         msg: channel.get_accept_channel(),
2596                                 });
2597                                 entry.insert(channel);
2598                         }
2599                 }
2600                 Ok(())
2601         }
2602
2603         fn internal_accept_channel(&self, counterparty_node_id: &PublicKey, their_features: InitFeatures, msg: &msgs::AcceptChannel) -> Result<(), MsgHandleErrInternal> {
2604                 let (value, output_script, user_id) = {
2605                         let mut channel_lock = self.channel_state.lock().unwrap();
2606                         let channel_state = &mut *channel_lock;
2607                         match channel_state.by_id.entry(msg.temporary_channel_id) {
2608                                 hash_map::Entry::Occupied(mut chan) => {
2609                                         if chan.get().get_counterparty_node_id() != *counterparty_node_id {
2610                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.temporary_channel_id));
2611                                         }
2612                                         try_chan_entry!(self, chan.get_mut().accept_channel(&msg, &self.default_configuration, their_features), channel_state, chan);
2613                                         (chan.get().get_value_satoshis(), chan.get().get_funding_redeemscript().to_v0_p2wsh(), chan.get().get_user_id())
2614                                 },
2615                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.temporary_channel_id))
2616                         }
2617                 };
2618                 let mut pending_events = self.pending_events.lock().unwrap();
2619                 pending_events.push(events::Event::FundingGenerationReady {
2620                         temporary_channel_id: msg.temporary_channel_id,
2621                         channel_value_satoshis: value,
2622                         output_script,
2623                         user_channel_id: user_id,
2624                 });
2625                 Ok(())
2626         }
2627
2628         fn internal_funding_created(&self, counterparty_node_id: &PublicKey, msg: &msgs::FundingCreated) -> Result<(), MsgHandleErrInternal> {
2629                 let ((funding_msg, monitor), mut chan) = {
2630                         let best_block = *self.best_block.read().unwrap();
2631                         let mut channel_lock = self.channel_state.lock().unwrap();
2632                         let channel_state = &mut *channel_lock;
2633                         match channel_state.by_id.entry(msg.temporary_channel_id.clone()) {
2634                                 hash_map::Entry::Occupied(mut chan) => {
2635                                         if chan.get().get_counterparty_node_id() != *counterparty_node_id {
2636                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.temporary_channel_id));
2637                                         }
2638                                         (try_chan_entry!(self, chan.get_mut().funding_created(msg, best_block, &self.logger), channel_state, chan), chan.remove())
2639                                 },
2640                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.temporary_channel_id))
2641                         }
2642                 };
2643                 // Because we have exclusive ownership of the channel here we can release the channel_state
2644                 // lock before watch_channel
2645                 if let Err(e) = self.chain_monitor.watch_channel(monitor.get_funding_txo().0, monitor) {
2646                         match e {
2647                                 ChannelMonitorUpdateErr::PermanentFailure => {
2648                                         // Note that we reply with the new channel_id in error messages if we gave up on the
2649                                         // channel, not the temporary_channel_id. This is compatible with ourselves, but the
2650                                         // spec is somewhat ambiguous here. Not a huge deal since we'll send error messages for
2651                                         // any messages referencing a previously-closed channel anyway.
2652                                         // We do not do a force-close here as that would generate a monitor update for
2653                                         // a monitor that we didn't manage to store (and that we don't care about - we
2654                                         // don't respond with the funding_signed so the channel can never go on chain).
2655                                         let (_monitor_update, failed_htlcs) = chan.force_shutdown(true);
2656                                         assert!(failed_htlcs.is_empty());
2657                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("ChannelMonitor storage failure".to_owned(), funding_msg.channel_id));
2658                                 },
2659                                 ChannelMonitorUpdateErr::TemporaryFailure => {
2660                                         // There's no problem signing a counterparty's funding transaction if our monitor
2661                                         // hasn't persisted to disk yet - we can't lose money on a transaction that we haven't
2662                                         // accepted payment from yet. We do, however, need to wait to send our funding_locked
2663                                         // until we have persisted our monitor.
2664                                         chan.monitor_update_failed(false, false, Vec::new(), Vec::new());
2665                                 },
2666                         }
2667                 }
2668                 let mut channel_state_lock = self.channel_state.lock().unwrap();
2669                 let channel_state = &mut *channel_state_lock;
2670                 match channel_state.by_id.entry(funding_msg.channel_id) {
2671                         hash_map::Entry::Occupied(_) => {
2672                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Already had channel with the new channel_id".to_owned(), funding_msg.channel_id))
2673                         },
2674                         hash_map::Entry::Vacant(e) => {
2675                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendFundingSigned {
2676                                         node_id: counterparty_node_id.clone(),
2677                                         msg: funding_msg,
2678                                 });
2679                                 e.insert(chan);
2680                         }
2681                 }
2682                 Ok(())
2683         }
2684
2685         fn internal_funding_signed(&self, counterparty_node_id: &PublicKey, msg: &msgs::FundingSigned) -> Result<(), MsgHandleErrInternal> {
2686                 let funding_tx = {
2687                         let best_block = *self.best_block.read().unwrap();
2688                         let mut channel_lock = self.channel_state.lock().unwrap();
2689                         let channel_state = &mut *channel_lock;
2690                         match channel_state.by_id.entry(msg.channel_id) {
2691                                 hash_map::Entry::Occupied(mut chan) => {
2692                                         if chan.get().get_counterparty_node_id() != *counterparty_node_id {
2693                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
2694                                         }
2695                                         let (monitor, funding_tx) = match chan.get_mut().funding_signed(&msg, best_block, &self.logger) {
2696                                                 Ok(update) => update,
2697                                                 Err(e) => try_chan_entry!(self, Err(e), channel_state, chan),
2698                                         };
2699                                         if let Err(e) = self.chain_monitor.watch_channel(chan.get().get_funding_txo().unwrap(), monitor) {
2700                                                 return_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::RevokeAndACKFirst, false, false);
2701                                         }
2702                                         funding_tx
2703                                 },
2704                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
2705                         }
2706                 };
2707                 self.tx_broadcaster.broadcast_transaction(&funding_tx);
2708                 Ok(())
2709         }
2710
2711         fn internal_funding_locked(&self, counterparty_node_id: &PublicKey, msg: &msgs::FundingLocked) -> Result<(), MsgHandleErrInternal> {
2712                 let mut channel_state_lock = self.channel_state.lock().unwrap();
2713                 let channel_state = &mut *channel_state_lock;
2714                 match channel_state.by_id.entry(msg.channel_id) {
2715                         hash_map::Entry::Occupied(mut chan) => {
2716                                 if chan.get().get_counterparty_node_id() != *counterparty_node_id {
2717                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
2718                                 }
2719                                 try_chan_entry!(self, chan.get_mut().funding_locked(&msg), channel_state, chan);
2720                                 if let Some(announcement_sigs) = self.get_announcement_sigs(chan.get()) {
2721                                         log_trace!(self.logger, "Sending announcement_signatures for {} in response to funding_locked", log_bytes!(chan.get().channel_id()));
2722                                         // If we see locking block before receiving remote funding_locked, we broadcast our
2723                                         // announcement_sigs at remote funding_locked reception. If we receive remote
2724                                         // funding_locked before seeing locking block, we broadcast our announcement_sigs at locking
2725                                         // block connection. We should guanrantee to broadcast announcement_sigs to our peer whatever
2726                                         // the order of the events but our peer may not receive it due to disconnection. The specs
2727                                         // lacking an acknowledgement for announcement_sigs we may have to re-send them at peer
2728                                         // connection in the future if simultaneous misses by both peers due to network/hardware
2729                                         // failures is an issue. Note, to achieve its goal, only one of the announcement_sigs needs
2730                                         // to be received, from then sigs are going to be flood to the whole network.
2731                                         channel_state.pending_msg_events.push(events::MessageSendEvent::SendAnnouncementSignatures {
2732                                                 node_id: counterparty_node_id.clone(),
2733                                                 msg: announcement_sigs,
2734                                         });
2735                                 }
2736                                 Ok(())
2737                         },
2738                         hash_map::Entry::Vacant(_) => Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
2739                 }
2740         }
2741
2742         fn internal_shutdown(&self, counterparty_node_id: &PublicKey, their_features: &InitFeatures, msg: &msgs::Shutdown) -> Result<(), MsgHandleErrInternal> {
2743                 let (mut dropped_htlcs, chan_option) = {
2744                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2745                         let channel_state = &mut *channel_state_lock;
2746
2747                         match channel_state.by_id.entry(msg.channel_id.clone()) {
2748                                 hash_map::Entry::Occupied(mut chan_entry) => {
2749                                         if chan_entry.get().get_counterparty_node_id() != *counterparty_node_id {
2750                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
2751                                         }
2752                                         let (shutdown, closing_signed, dropped_htlcs) = try_chan_entry!(self, chan_entry.get_mut().shutdown(&self.fee_estimator, &their_features, &msg), channel_state, chan_entry);
2753                                         if let Some(msg) = shutdown {
2754                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendShutdown {
2755                                                         node_id: counterparty_node_id.clone(),
2756                                                         msg,
2757                                                 });
2758                                         }
2759                                         if let Some(msg) = closing_signed {
2760                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendClosingSigned {
2761                                                         node_id: counterparty_node_id.clone(),
2762                                                         msg,
2763                                                 });
2764                                         }
2765                                         if chan_entry.get().is_shutdown() {
2766                                                 if let Some(short_id) = chan_entry.get().get_short_channel_id() {
2767                                                         channel_state.short_to_id.remove(&short_id);
2768                                                 }
2769                                                 (dropped_htlcs, Some(chan_entry.remove_entry().1))
2770                                         } else { (dropped_htlcs, None) }
2771                                 },
2772                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
2773                         }
2774                 };
2775                 for htlc_source in dropped_htlcs.drain(..) {
2776                         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() });
2777                 }
2778                 if let Some(chan) = chan_option {
2779                         if let Ok(update) = self.get_channel_update(&chan) {
2780                                 let mut channel_state = self.channel_state.lock().unwrap();
2781                                 channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
2782                                         msg: update
2783                                 });
2784                         }
2785                 }
2786                 Ok(())
2787         }
2788
2789         fn internal_closing_signed(&self, counterparty_node_id: &PublicKey, msg: &msgs::ClosingSigned) -> Result<(), MsgHandleErrInternal> {
2790                 let (tx, chan_option) = {
2791                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2792                         let channel_state = &mut *channel_state_lock;
2793                         match channel_state.by_id.entry(msg.channel_id.clone()) {
2794                                 hash_map::Entry::Occupied(mut chan_entry) => {
2795                                         if chan_entry.get().get_counterparty_node_id() != *counterparty_node_id {
2796                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
2797                                         }
2798                                         let (closing_signed, tx) = try_chan_entry!(self, chan_entry.get_mut().closing_signed(&self.fee_estimator, &msg), channel_state, chan_entry);
2799                                         if let Some(msg) = closing_signed {
2800                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendClosingSigned {
2801                                                         node_id: counterparty_node_id.clone(),
2802                                                         msg,
2803                                                 });
2804                                         }
2805                                         if tx.is_some() {
2806                                                 // We're done with this channel, we've got a signed closing transaction and
2807                                                 // will send the closing_signed back to the remote peer upon return. This
2808                                                 // also implies there are no pending HTLCs left on the channel, so we can
2809                                                 // fully delete it from tracking (the channel monitor is still around to
2810                                                 // watch for old state broadcasts)!
2811                                                 if let Some(short_id) = chan_entry.get().get_short_channel_id() {
2812                                                         channel_state.short_to_id.remove(&short_id);
2813                                                 }
2814                                                 (tx, Some(chan_entry.remove_entry().1))
2815                                         } else { (tx, None) }
2816                                 },
2817                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
2818                         }
2819                 };
2820                 if let Some(broadcast_tx) = tx {
2821                         log_trace!(self.logger, "Broadcast onchain {}", log_tx!(broadcast_tx));
2822                         self.tx_broadcaster.broadcast_transaction(&broadcast_tx);
2823                 }
2824                 if let Some(chan) = chan_option {
2825                         if let Ok(update) = self.get_channel_update(&chan) {
2826                                 let mut channel_state = self.channel_state.lock().unwrap();
2827                                 channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
2828                                         msg: update
2829                                 });
2830                         }
2831                 }
2832                 Ok(())
2833         }
2834
2835         fn internal_update_add_htlc(&self, counterparty_node_id: &PublicKey, msg: &msgs::UpdateAddHTLC) -> Result<(), MsgHandleErrInternal> {
2836                 //TODO: BOLT 4 points out a specific attack where a peer may re-send an onion packet and
2837                 //determine the state of the payment based on our response/if we forward anything/the time
2838                 //we take to respond. We should take care to avoid allowing such an attack.
2839                 //
2840                 //TODO: There exists a further attack where a node may garble the onion data, forward it to
2841                 //us repeatedly garbled in different ways, and compare our error messages, which are
2842                 //encrypted with the same key. It's not immediately obvious how to usefully exploit that,
2843                 //but we should prevent it anyway.
2844
2845                 let (pending_forward_info, mut channel_state_lock) = self.decode_update_add_htlc_onion(msg);
2846                 let channel_state = &mut *channel_state_lock;
2847
2848                 match channel_state.by_id.entry(msg.channel_id) {
2849                         hash_map::Entry::Occupied(mut chan) => {
2850                                 if chan.get().get_counterparty_node_id() != *counterparty_node_id {
2851                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
2852                                 }
2853
2854                                 let create_pending_htlc_status = |chan: &Channel<Signer>, pending_forward_info: PendingHTLCStatus, error_code: u16| {
2855                                         // Ensure error_code has the UPDATE flag set, since by default we send a
2856                                         // channel update along as part of failing the HTLC.
2857                                         assert!((error_code & 0x1000) != 0);
2858                                         // If the update_add is completely bogus, the call will Err and we will close,
2859                                         // but if we've sent a shutdown and they haven't acknowledged it yet, we just
2860                                         // want to reject the new HTLC and fail it backwards instead of forwarding.
2861                                         match pending_forward_info {
2862                                                 PendingHTLCStatus::Forward(PendingHTLCInfo { ref incoming_shared_secret, .. }) => {
2863                                                         let reason = if let Ok(upd) = self.get_channel_update(chan) {
2864                                                                 onion_utils::build_first_hop_failure_packet(incoming_shared_secret, error_code, &{
2865                                                                         let mut res = Vec::with_capacity(8 + 128);
2866                                                                         // TODO: underspecified, follow https://github.com/lightningnetwork/lightning-rfc/issues/791
2867                                                                         res.extend_from_slice(&byte_utils::be16_to_array(0));
2868                                                                         res.extend_from_slice(&upd.encode_with_len()[..]);
2869                                                                         res
2870                                                                 }[..])
2871                                                         } else {
2872                                                                 // The only case where we'd be unable to
2873                                                                 // successfully get a channel update is if the
2874                                                                 // channel isn't in the fully-funded state yet,
2875                                                                 // implying our counterparty is trying to route
2876                                                                 // payments over the channel back to themselves
2877                                                                 // (cause no one else should know the short_id
2878                                                                 // is a lightning channel yet). We should have
2879                                                                 // no problem just calling this
2880                                                                 // unknown_next_peer (0x4000|10).
2881                                                                 onion_utils::build_first_hop_failure_packet(incoming_shared_secret, 0x4000|10, &[])
2882                                                         };
2883                                                         let msg = msgs::UpdateFailHTLC {
2884                                                                 channel_id: msg.channel_id,
2885                                                                 htlc_id: msg.htlc_id,
2886                                                                 reason
2887                                                         };
2888                                                         PendingHTLCStatus::Fail(HTLCFailureMsg::Relay(msg))
2889                                                 },
2890                                                 _ => pending_forward_info
2891                                         }
2892                                 };
2893                                 try_chan_entry!(self, chan.get_mut().update_add_htlc(&msg, pending_forward_info, create_pending_htlc_status, &self.logger), channel_state, chan);
2894                         },
2895                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
2896                 }
2897                 Ok(())
2898         }
2899
2900         fn internal_update_fulfill_htlc(&self, counterparty_node_id: &PublicKey, msg: &msgs::UpdateFulfillHTLC) -> Result<(), MsgHandleErrInternal> {
2901                 let mut channel_lock = self.channel_state.lock().unwrap();
2902                 let htlc_source = {
2903                         let channel_state = &mut *channel_lock;
2904                         match channel_state.by_id.entry(msg.channel_id) {
2905                                 hash_map::Entry::Occupied(mut chan) => {
2906                                         if chan.get().get_counterparty_node_id() != *counterparty_node_id {
2907                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
2908                                         }
2909                                         try_chan_entry!(self, chan.get_mut().update_fulfill_htlc(&msg), channel_state, chan)
2910                                 },
2911                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
2912                         }
2913                 };
2914                 self.claim_funds_internal(channel_lock, htlc_source, msg.payment_preimage.clone());
2915                 Ok(())
2916         }
2917
2918         fn internal_update_fail_htlc(&self, counterparty_node_id: &PublicKey, msg: &msgs::UpdateFailHTLC) -> Result<(), MsgHandleErrInternal> {
2919                 let mut channel_lock = self.channel_state.lock().unwrap();
2920                 let channel_state = &mut *channel_lock;
2921                 match channel_state.by_id.entry(msg.channel_id) {
2922                         hash_map::Entry::Occupied(mut chan) => {
2923                                 if chan.get().get_counterparty_node_id() != *counterparty_node_id {
2924                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
2925                                 }
2926                                 try_chan_entry!(self, chan.get_mut().update_fail_htlc(&msg, HTLCFailReason::LightningError { err: msg.reason.clone() }), channel_state, chan);
2927                         },
2928                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
2929                 }
2930                 Ok(())
2931         }
2932
2933         fn internal_update_fail_malformed_htlc(&self, counterparty_node_id: &PublicKey, msg: &msgs::UpdateFailMalformedHTLC) -> Result<(), MsgHandleErrInternal> {
2934                 let mut channel_lock = self.channel_state.lock().unwrap();
2935                 let channel_state = &mut *channel_lock;
2936                 match channel_state.by_id.entry(msg.channel_id) {
2937                         hash_map::Entry::Occupied(mut chan) => {
2938                                 if chan.get().get_counterparty_node_id() != *counterparty_node_id {
2939                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
2940                                 }
2941                                 if (msg.failure_code & 0x8000) == 0 {
2942                                         let chan_err: ChannelError = ChannelError::Close("Got update_fail_malformed_htlc with BADONION not set".to_owned());
2943                                         try_chan_entry!(self, Err(chan_err), channel_state, chan);
2944                                 }
2945                                 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);
2946                                 Ok(())
2947                         },
2948                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
2949                 }
2950         }
2951
2952         fn internal_commitment_signed(&self, counterparty_node_id: &PublicKey, msg: &msgs::CommitmentSigned) -> Result<(), MsgHandleErrInternal> {
2953                 let mut channel_state_lock = self.channel_state.lock().unwrap();
2954                 let channel_state = &mut *channel_state_lock;
2955                 match channel_state.by_id.entry(msg.channel_id) {
2956                         hash_map::Entry::Occupied(mut chan) => {
2957                                 if chan.get().get_counterparty_node_id() != *counterparty_node_id {
2958                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
2959                                 }
2960                                 let (revoke_and_ack, commitment_signed, closing_signed, monitor_update) =
2961                                         match chan.get_mut().commitment_signed(&msg, &self.fee_estimator, &self.logger) {
2962                                                 Err((None, e)) => try_chan_entry!(self, Err(e), channel_state, chan),
2963                                                 Err((Some(update), e)) => {
2964                                                         assert!(chan.get().is_awaiting_monitor_update());
2965                                                         let _ = self.chain_monitor.update_channel(chan.get().get_funding_txo().unwrap(), update);
2966                                                         try_chan_entry!(self, Err(e), channel_state, chan);
2967                                                         unreachable!();
2968                                                 },
2969                                                 Ok(res) => res
2970                                         };
2971                                 if let Err(e) = self.chain_monitor.update_channel(chan.get().get_funding_txo().unwrap(), monitor_update) {
2972                                         return_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::RevokeAndACKFirst, true, commitment_signed.is_some());
2973                                         //TODO: Rebroadcast closing_signed if present on monitor update restoration
2974                                 }
2975                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendRevokeAndACK {
2976                                         node_id: counterparty_node_id.clone(),
2977                                         msg: revoke_and_ack,
2978                                 });
2979                                 if let Some(msg) = commitment_signed {
2980                                         channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
2981                                                 node_id: counterparty_node_id.clone(),
2982                                                 updates: msgs::CommitmentUpdate {
2983                                                         update_add_htlcs: Vec::new(),
2984                                                         update_fulfill_htlcs: Vec::new(),
2985                                                         update_fail_htlcs: Vec::new(),
2986                                                         update_fail_malformed_htlcs: Vec::new(),
2987                                                         update_fee: None,
2988                                                         commitment_signed: msg,
2989                                                 },
2990                                         });
2991                                 }
2992                                 if let Some(msg) = closing_signed {
2993                                         channel_state.pending_msg_events.push(events::MessageSendEvent::SendClosingSigned {
2994                                                 node_id: counterparty_node_id.clone(),
2995                                                 msg,
2996                                         });
2997                                 }
2998                                 Ok(())
2999                         },
3000                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
3001                 }
3002         }
3003
3004         #[inline]
3005         fn forward_htlcs(&self, per_source_pending_forwards: &mut [(u64, OutPoint, Vec<(PendingHTLCInfo, u64)>)]) {
3006                 for &mut (prev_short_channel_id, prev_funding_outpoint, ref mut pending_forwards) in per_source_pending_forwards {
3007                         let mut forward_event = None;
3008                         if !pending_forwards.is_empty() {
3009                                 let mut channel_state = self.channel_state.lock().unwrap();
3010                                 if channel_state.forward_htlcs.is_empty() {
3011                                         forward_event = Some(Duration::from_millis(MIN_HTLC_RELAY_HOLDING_CELL_MILLIS))
3012                                 }
3013                                 for (forward_info, prev_htlc_id) in pending_forwards.drain(..) {
3014                                         match channel_state.forward_htlcs.entry(match forward_info.routing {
3015                                                         PendingHTLCRouting::Forward { short_channel_id, .. } => short_channel_id,
3016                                                         PendingHTLCRouting::Receive { .. } => 0,
3017                                         }) {
3018                                                 hash_map::Entry::Occupied(mut entry) => {
3019                                                         entry.get_mut().push(HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_funding_outpoint,
3020                                                                                                         prev_htlc_id, forward_info });
3021                                                 },
3022                                                 hash_map::Entry::Vacant(entry) => {
3023                                                         entry.insert(vec!(HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_funding_outpoint,
3024                                                                                                      prev_htlc_id, forward_info }));
3025                                                 }
3026                                         }
3027                                 }
3028                         }
3029                         match forward_event {
3030                                 Some(time) => {
3031                                         let mut pending_events = self.pending_events.lock().unwrap();
3032                                         pending_events.push(events::Event::PendingHTLCsForwardable {
3033                                                 time_forwardable: time
3034                                         });
3035                                 }
3036                                 None => {},
3037                         }
3038                 }
3039         }
3040
3041         fn internal_revoke_and_ack(&self, counterparty_node_id: &PublicKey, msg: &msgs::RevokeAndACK) -> Result<(), MsgHandleErrInternal> {
3042                 let mut htlcs_to_fail = Vec::new();
3043                 let res = loop {
3044                         let mut channel_state_lock = self.channel_state.lock().unwrap();
3045                         let channel_state = &mut *channel_state_lock;
3046                         match channel_state.by_id.entry(msg.channel_id) {
3047                                 hash_map::Entry::Occupied(mut chan) => {
3048                                         if chan.get().get_counterparty_node_id() != *counterparty_node_id {
3049                                                 break Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
3050                                         }
3051                                         let was_frozen_for_monitor = chan.get().is_awaiting_monitor_update();
3052                                         let (commitment_update, pending_forwards, pending_failures, closing_signed, monitor_update, htlcs_to_fail_in) =
3053                                                 break_chan_entry!(self, chan.get_mut().revoke_and_ack(&msg, &self.fee_estimator, &self.logger), channel_state, chan);
3054                                         htlcs_to_fail = htlcs_to_fail_in;
3055                                         if let Err(e) = self.chain_monitor.update_channel(chan.get().get_funding_txo().unwrap(), monitor_update) {
3056                                                 if was_frozen_for_monitor {
3057                                                         assert!(commitment_update.is_none() && closing_signed.is_none() && pending_forwards.is_empty() && pending_failures.is_empty());
3058                                                         break Err(MsgHandleErrInternal::ignore_no_close("Previous monitor update failure prevented responses to RAA".to_owned()));
3059                                                 } else {
3060                                                         if let Err(e) = handle_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::CommitmentFirst, false, commitment_update.is_some(), pending_forwards, pending_failures) {
3061                                                                 break Err(e);
3062                                                         } else { unreachable!(); }
3063                                                 }
3064                                         }
3065                                         if let Some(updates) = commitment_update {
3066                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
3067                                                         node_id: counterparty_node_id.clone(),
3068                                                         updates,
3069                                                 });
3070                                         }
3071                                         if let Some(msg) = closing_signed {
3072                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendClosingSigned {
3073                                                         node_id: counterparty_node_id.clone(),
3074                                                         msg,
3075                                                 });
3076                                         }
3077                                         break Ok((pending_forwards, pending_failures, chan.get().get_short_channel_id().expect("RAA should only work on a short-id-available channel"), chan.get().get_funding_txo().unwrap()))
3078                                 },
3079                                 hash_map::Entry::Vacant(_) => break Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
3080                         }
3081                 };
3082                 self.fail_holding_cell_htlcs(htlcs_to_fail, msg.channel_id);
3083                 match res {
3084                         Ok((pending_forwards, mut pending_failures, short_channel_id, channel_outpoint)) => {
3085                                 for failure in pending_failures.drain(..) {
3086                                         self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), failure.0, &failure.1, failure.2);
3087                                 }
3088                                 self.forward_htlcs(&mut [(short_channel_id, channel_outpoint, pending_forwards)]);
3089                                 Ok(())
3090                         },
3091                         Err(e) => Err(e)
3092                 }
3093         }
3094
3095         fn internal_update_fee(&self, counterparty_node_id: &PublicKey, msg: &msgs::UpdateFee) -> Result<(), MsgHandleErrInternal> {
3096                 let mut channel_lock = self.channel_state.lock().unwrap();
3097                 let channel_state = &mut *channel_lock;
3098                 match channel_state.by_id.entry(msg.channel_id) {
3099                         hash_map::Entry::Occupied(mut chan) => {
3100                                 if chan.get().get_counterparty_node_id() != *counterparty_node_id {
3101                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
3102                                 }
3103                                 try_chan_entry!(self, chan.get_mut().update_fee(&self.fee_estimator, &msg), channel_state, chan);
3104                         },
3105                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
3106                 }
3107                 Ok(())
3108         }
3109
3110         fn internal_announcement_signatures(&self, counterparty_node_id: &PublicKey, msg: &msgs::AnnouncementSignatures) -> Result<(), MsgHandleErrInternal> {
3111                 let mut channel_state_lock = self.channel_state.lock().unwrap();
3112                 let channel_state = &mut *channel_state_lock;
3113
3114                 match channel_state.by_id.entry(msg.channel_id) {
3115                         hash_map::Entry::Occupied(mut chan) => {
3116                                 if chan.get().get_counterparty_node_id() != *counterparty_node_id {
3117                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
3118                                 }
3119                                 if !chan.get().is_usable() {
3120                                         return Err(MsgHandleErrInternal::from_no_close(LightningError{err: "Got an announcement_signatures before we were ready for it".to_owned(), action: msgs::ErrorAction::IgnoreError}));
3121                                 }
3122
3123                                 let our_node_id = self.get_our_node_id();
3124                                 let (announcement, our_bitcoin_sig) =
3125                                         try_chan_entry!(self, chan.get_mut().get_channel_announcement(our_node_id.clone(), self.genesis_hash.clone()), channel_state, chan);
3126
3127                                 let were_node_one = announcement.node_id_1 == our_node_id;
3128                                 let msghash = hash_to_message!(&Sha256dHash::hash(&announcement.encode()[..])[..]);
3129                                 {
3130                                         let their_node_key = if were_node_one { &announcement.node_id_2 } else { &announcement.node_id_1 };
3131                                         let their_bitcoin_key = if were_node_one { &announcement.bitcoin_key_2 } else { &announcement.bitcoin_key_1 };
3132                                         match (self.secp_ctx.verify(&msghash, &msg.node_signature, their_node_key),
3133                                                    self.secp_ctx.verify(&msghash, &msg.bitcoin_signature, their_bitcoin_key)) {
3134                                                 (Err(e), _) => {
3135                                                         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));
3136                                                         try_chan_entry!(self, Err(chan_err), channel_state, chan);
3137                                                 },
3138                                                 (_, Err(e)) => {
3139                                                         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));
3140                                                         try_chan_entry!(self, Err(chan_err), channel_state, chan);
3141                                                 },
3142                                                 _ => {}
3143                                         }
3144                                 }
3145
3146                                 let our_node_sig = self.secp_ctx.sign(&msghash, &self.our_network_key);
3147
3148                                 channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelAnnouncement {
3149                                         msg: msgs::ChannelAnnouncement {
3150                                                 node_signature_1: if were_node_one { our_node_sig } else { msg.node_signature },
3151                                                 node_signature_2: if were_node_one { msg.node_signature } else { our_node_sig },
3152                                                 bitcoin_signature_1: if were_node_one { our_bitcoin_sig } else { msg.bitcoin_signature },
3153                                                 bitcoin_signature_2: if were_node_one { msg.bitcoin_signature } else { our_bitcoin_sig },
3154                                                 contents: announcement,
3155                                         },
3156                                         update_msg: self.get_channel_update(chan.get()).unwrap(), // can only fail if we're not in a ready state
3157                                 });
3158                         },
3159                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
3160                 }
3161                 Ok(())
3162         }
3163
3164         fn internal_channel_update(&self, counterparty_node_id: &PublicKey, msg: &msgs::ChannelUpdate) -> Result<(), MsgHandleErrInternal> {
3165                 let mut channel_state_lock = self.channel_state.lock().unwrap();
3166                 let channel_state = &mut *channel_state_lock;
3167                 let chan_id = match channel_state.short_to_id.get(&msg.contents.short_channel_id) {
3168                         Some(chan_id) => chan_id.clone(),
3169                         None => {
3170                                 // It's not a local channel
3171                                 return Ok(())
3172                         }
3173                 };
3174                 match channel_state.by_id.entry(chan_id) {
3175                         hash_map::Entry::Occupied(mut chan) => {
3176                                 if chan.get().get_counterparty_node_id() != *counterparty_node_id {
3177                                         // TODO: see issue #153, need a consistent behavior on obnoxious behavior from random node
3178                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), chan_id));
3179                                 }
3180                                 try_chan_entry!(self, chan.get_mut().channel_update(&msg), channel_state, chan);
3181                         },
3182                         hash_map::Entry::Vacant(_) => unreachable!()
3183                 }
3184                 Ok(())
3185         }
3186
3187         fn internal_channel_reestablish(&self, counterparty_node_id: &PublicKey, msg: &msgs::ChannelReestablish) -> Result<(), MsgHandleErrInternal> {
3188                 let mut channel_state_lock = self.channel_state.lock().unwrap();
3189                 let channel_state = &mut *channel_state_lock;
3190
3191                 match channel_state.by_id.entry(msg.channel_id) {
3192                         hash_map::Entry::Occupied(mut chan) => {
3193                                 if chan.get().get_counterparty_node_id() != *counterparty_node_id {
3194                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
3195                                 }
3196                                 // Currently, we expect all holding cell update_adds to be dropped on peer
3197                                 // disconnect, so Channel's reestablish will never hand us any holding cell
3198                                 // freed HTLCs to fail backwards. If in the future we no longer drop pending
3199                                 // add-HTLCs on disconnect, we may be handed HTLCs to fail backwards here.
3200                                 let (funding_locked, revoke_and_ack, commitment_update, monitor_update_opt, mut order, shutdown) =
3201                                         try_chan_entry!(self, chan.get_mut().channel_reestablish(msg, &self.logger), channel_state, chan);
3202                                 if let Some(monitor_update) = monitor_update_opt {
3203                                         if let Err(e) = self.chain_monitor.update_channel(chan.get().get_funding_txo().unwrap(), monitor_update) {
3204                                                 // channel_reestablish doesn't guarantee the order it returns is sensical
3205                                                 // for the messages it returns, but if we're setting what messages to
3206                                                 // re-transmit on monitor update success, we need to make sure it is sane.
3207                                                 if revoke_and_ack.is_none() {
3208                                                         order = RAACommitmentOrder::CommitmentFirst;
3209                                                 }
3210                                                 if commitment_update.is_none() {
3211                                                         order = RAACommitmentOrder::RevokeAndACKFirst;
3212                                                 }
3213                                                 return_monitor_err!(self, e, channel_state, chan, order, revoke_and_ack.is_some(), commitment_update.is_some());
3214                                                 //TODO: Resend the funding_locked if needed once we get the monitor running again
3215                                         }
3216                                 }
3217                                 if let Some(msg) = funding_locked {
3218                                         channel_state.pending_msg_events.push(events::MessageSendEvent::SendFundingLocked {
3219                                                 node_id: counterparty_node_id.clone(),
3220                                                 msg
3221                                         });
3222                                 }
3223                                 macro_rules! send_raa { () => {
3224                                         if let Some(msg) = revoke_and_ack {
3225                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendRevokeAndACK {
3226                                                         node_id: counterparty_node_id.clone(),
3227                                                         msg
3228                                                 });
3229                                         }
3230                                 } }
3231                                 macro_rules! send_cu { () => {
3232                                         if let Some(updates) = commitment_update {
3233                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
3234                                                         node_id: counterparty_node_id.clone(),
3235                                                         updates
3236                                                 });
3237                                         }
3238                                 } }
3239                                 match order {
3240                                         RAACommitmentOrder::RevokeAndACKFirst => {
3241                                                 send_raa!();
3242                                                 send_cu!();
3243                                         },
3244                                         RAACommitmentOrder::CommitmentFirst => {
3245                                                 send_cu!();
3246                                                 send_raa!();
3247                                         },
3248                                 }
3249                                 if let Some(msg) = shutdown {
3250                                         channel_state.pending_msg_events.push(events::MessageSendEvent::SendShutdown {
3251                                                 node_id: counterparty_node_id.clone(),
3252                                                 msg,
3253                                         });
3254                                 }
3255                                 Ok(())
3256                         },
3257                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
3258                 }
3259         }
3260
3261         /// Begin Update fee process. Allowed only on an outbound channel.
3262         /// If successful, will generate a UpdateHTLCs event, so you should probably poll
3263         /// PeerManager::process_events afterwards.
3264         /// Note: This API is likely to change!
3265         /// (C-not exported) Cause its doc(hidden) anyway
3266         #[doc(hidden)]
3267         pub fn update_fee(&self, channel_id: [u8;32], feerate_per_kw: u32) -> Result<(), APIError> {
3268                 let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
3269                 let counterparty_node_id;
3270                 let err: Result<(), _> = loop {
3271                         let mut channel_state_lock = self.channel_state.lock().unwrap();
3272                         let channel_state = &mut *channel_state_lock;
3273
3274                         match channel_state.by_id.entry(channel_id) {
3275                                 hash_map::Entry::Vacant(_) => return Err(APIError::APIMisuseError{err: format!("Failed to find corresponding channel for id {}", channel_id.to_hex())}),
3276                                 hash_map::Entry::Occupied(mut chan) => {
3277                                         if !chan.get().is_outbound() {
3278                                                 return Err(APIError::APIMisuseError{err: "update_fee cannot be sent for an inbound channel".to_owned()});
3279                                         }
3280                                         if chan.get().is_awaiting_monitor_update() {
3281                                                 return Err(APIError::MonitorUpdateFailed);
3282                                         }
3283                                         if !chan.get().is_live() {
3284                                                 return Err(APIError::ChannelUnavailable{err: "Channel is either not yet fully established or peer is currently disconnected".to_owned()});
3285                                         }
3286                                         counterparty_node_id = chan.get().get_counterparty_node_id();
3287                                         if let Some((update_fee, commitment_signed, monitor_update)) =
3288                                                         break_chan_entry!(self, chan.get_mut().send_update_fee_and_commit(feerate_per_kw, &self.logger), channel_state, chan)
3289                                         {
3290                                                 if let Err(_e) = self.chain_monitor.update_channel(chan.get().get_funding_txo().unwrap(), monitor_update) {
3291                                                         unimplemented!();
3292                                                 }
3293                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
3294                                                         node_id: chan.get().get_counterparty_node_id(),
3295                                                         updates: msgs::CommitmentUpdate {
3296                                                                 update_add_htlcs: Vec::new(),
3297                                                                 update_fulfill_htlcs: Vec::new(),
3298                                                                 update_fail_htlcs: Vec::new(),
3299                                                                 update_fail_malformed_htlcs: Vec::new(),
3300                                                                 update_fee: Some(update_fee),
3301                                                                 commitment_signed,
3302                                                         },
3303                                                 });
3304                                         }
3305                                 },
3306                         }
3307                         return Ok(())
3308                 };
3309
3310                 match handle_error!(self, err, counterparty_node_id) {
3311                         Ok(_) => unreachable!(),
3312                         Err(e) => { Err(APIError::APIMisuseError { err: e.err })}
3313                 }
3314         }
3315
3316         /// Process pending events from the `chain::Watch`.
3317         fn process_pending_monitor_events(&self) {
3318                 let mut failed_channels = Vec::new();
3319                 {
3320                         for monitor_event in self.chain_monitor.release_pending_monitor_events() {
3321                                 match monitor_event {
3322                                         MonitorEvent::HTLCEvent(htlc_update) => {
3323                                                 if let Some(preimage) = htlc_update.payment_preimage {
3324                                                         log_trace!(self.logger, "Claiming HTLC with preimage {} from our monitor", log_bytes!(preimage.0));
3325                                                         self.claim_funds_internal(self.channel_state.lock().unwrap(), htlc_update.source, preimage);
3326                                                 } else {
3327                                                         log_trace!(self.logger, "Failing HTLC with hash {} from our monitor", log_bytes!(htlc_update.payment_hash.0));
3328                                                         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() });
3329                                                 }
3330                                         },
3331                                         MonitorEvent::CommitmentTxBroadcasted(funding_outpoint) => {
3332                                                 let mut channel_lock = self.channel_state.lock().unwrap();
3333                                                 let channel_state = &mut *channel_lock;
3334                                                 let by_id = &mut channel_state.by_id;
3335                                                 let short_to_id = &mut channel_state.short_to_id;
3336                                                 let pending_msg_events = &mut channel_state.pending_msg_events;
3337                                                 if let Some(mut chan) = by_id.remove(&funding_outpoint.to_channel_id()) {
3338                                                         if let Some(short_id) = chan.get_short_channel_id() {
3339                                                                 short_to_id.remove(&short_id);
3340                                                         }
3341                                                         failed_channels.push(chan.force_shutdown(false));
3342                                                         if let Ok(update) = self.get_channel_update(&chan) {
3343                                                                 pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
3344                                                                         msg: update
3345                                                                 });
3346                                                         }
3347                                                         pending_msg_events.push(events::MessageSendEvent::HandleError {
3348                                                                 node_id: chan.get_counterparty_node_id(),
3349                                                                 action: msgs::ErrorAction::SendErrorMessage {
3350                                                                         msg: msgs::ErrorMessage { channel_id: chan.channel_id(), data: "Channel force-closed".to_owned() }
3351                                                                 },
3352                                                         });
3353                                                 }
3354                                         },
3355                                 }
3356                         }
3357                 }
3358
3359                 for failure in failed_channels.drain(..) {
3360                         self.finish_force_close_channel(failure);
3361                 }
3362         }
3363
3364         /// Handle a list of channel failures during a block_connected or block_disconnected call,
3365         /// pushing the channel monitor update (if any) to the background events queue and removing the
3366         /// Channel object.
3367         fn handle_init_event_channel_failures(&self, mut failed_channels: Vec<ShutdownResult>) {
3368                 for mut failure in failed_channels.drain(..) {
3369                         // Either a commitment transactions has been confirmed on-chain or
3370                         // Channel::block_disconnected detected that the funding transaction has been
3371                         // reorganized out of the main chain.
3372                         // We cannot broadcast our latest local state via monitor update (as
3373                         // Channel::force_shutdown tries to make us do) as we may still be in initialization,
3374                         // so we track the update internally and handle it when the user next calls
3375                         // timer_tick_occurred, guaranteeing we're running normally.
3376                         if let Some((funding_txo, update)) = failure.0.take() {
3377                                 assert_eq!(update.updates.len(), 1);
3378                                 if let ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast } = update.updates[0] {
3379                                         assert!(should_broadcast);
3380                                 } else { unreachable!(); }
3381                                 self.pending_background_events.lock().unwrap().push(BackgroundEvent::ClosingMonitorUpdate((funding_txo, update)));
3382                         }
3383                         self.finish_force_close_channel(failure);
3384                 }
3385         }
3386
3387         fn set_payment_hash_secret_map(&self, payment_hash: PaymentHash, payment_preimage: Option<PaymentPreimage>, min_value_msat: Option<u64>, invoice_expiry_delta_secs: u32, user_payment_id: u64) -> Result<PaymentSecret, APIError> {
3388                 assert!(invoice_expiry_delta_secs <= 60*60*24*365); // Sadly bitcoin timestamps are u32s, so panic before 2106
3389
3390                 let payment_secret = PaymentSecret(self.keys_manager.get_secure_random_bytes());
3391
3392                 let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
3393                 let mut payment_secrets = self.pending_inbound_payments.lock().unwrap();
3394                 match payment_secrets.entry(payment_hash) {
3395                         hash_map::Entry::Vacant(e) => {
3396                                 e.insert(PendingInboundPayment {
3397                                         payment_secret, min_value_msat, user_payment_id, payment_preimage,
3398                                         // We assume that highest_seen_timestamp is pretty close to the current time -
3399                                         // its updated when we receive a new block with the maximum time we've seen in
3400                                         // a header. It should never be more than two hours in the future.
3401                                         // Thus, we add two hours here as a buffer to ensure we absolutely
3402                                         // never fail a payment too early.
3403                                         // Note that we assume that received blocks have reasonably up-to-date
3404                                         // timestamps.
3405                                         expiry_time: self.highest_seen_timestamp.load(Ordering::Acquire) as u64 + invoice_expiry_delta_secs as u64 + 7200,
3406                                 });
3407                         },
3408                         hash_map::Entry::Occupied(_) => return Err(APIError::APIMisuseError { err: "Duplicate payment hash".to_owned() }),
3409                 }
3410                 Ok(payment_secret)
3411         }
3412
3413         /// Gets a payment secret and payment hash for use in an invoice given to a third party wishing
3414         /// to pay us.
3415         ///
3416         /// This differs from [`create_inbound_payment_for_hash`] only in that it generates the
3417         /// [`PaymentHash`] and [`PaymentPreimage`] for you, returning the first and storing the second.
3418         ///
3419         /// The [`PaymentPreimage`] will ultimately be returned to you in the [`PaymentReceived`], which
3420         /// will have the [`PaymentReceived::payment_preimage`] field filled in. That should then be
3421         /// passed directly to [`claim_funds`].
3422         ///
3423         /// See [`create_inbound_payment_for_hash`] for detailed documentation on behavior and requirements.
3424         ///
3425         /// [`claim_funds`]: Self::claim_funds
3426         /// [`PaymentReceived`]: events::Event::PaymentReceived
3427         /// [`PaymentReceived::payment_preimage`]: events::Event::PaymentReceived::payment_preimage
3428         /// [`create_inbound_payment_for_hash`]: Self::create_inbound_payment_for_hash
3429         pub fn create_inbound_payment(&self, min_value_msat: Option<u64>, invoice_expiry_delta_secs: u32, user_payment_id: u64) -> (PaymentHash, PaymentSecret) {
3430                 let payment_preimage = PaymentPreimage(self.keys_manager.get_secure_random_bytes());
3431                 let payment_hash = PaymentHash(Sha256::hash(&payment_preimage.0).into_inner());
3432
3433                 (payment_hash,
3434                         self.set_payment_hash_secret_map(payment_hash, Some(payment_preimage), min_value_msat, invoice_expiry_delta_secs, user_payment_id)
3435                                 .expect("RNG Generated Duplicate PaymentHash"))
3436         }
3437
3438         /// Gets a [`PaymentSecret`] for a given [`PaymentHash`], for which the payment preimage is
3439         /// stored external to LDK.
3440         ///
3441         /// A [`PaymentReceived`] event will only be generated if the [`PaymentSecret`] matches a
3442         /// payment secret fetched via this method or [`create_inbound_payment`], and which is at least
3443         /// the `min_value_msat` provided here, if one is provided.
3444         ///
3445         /// The [`PaymentHash`] (and corresponding [`PaymentPreimage`]) must be globally unique. This
3446         /// method may return an Err if another payment with the same payment_hash is still pending.
3447         ///
3448         /// `user_payment_id` will be provided back in [`PaymentReceived::user_payment_id`] events to
3449         /// allow tracking of which events correspond with which calls to this and
3450         /// [`create_inbound_payment`]. `user_payment_id` has no meaning inside of LDK, it is simply
3451         /// copied to events and otherwise ignored. It may be used to correlate PaymentReceived events
3452         /// with invoice metadata stored elsewhere.
3453         ///
3454         /// `min_value_msat` should be set if the invoice being generated contains a value. Any payment
3455         /// received for the returned [`PaymentHash`] will be required to be at least `min_value_msat`
3456         /// before a [`PaymentReceived`] event will be generated, ensuring that we do not provide the
3457         /// sender "proof-of-payment" unless they have paid the required amount.
3458         ///
3459         /// `invoice_expiry_delta_secs` describes the number of seconds that the invoice is valid for
3460         /// in excess of the current time. This should roughly match the expiry time set in the invoice.
3461         /// After this many seconds, we will remove the inbound payment, resulting in any attempts to
3462         /// pay the invoice failing. The BOLT spec suggests 7,200 secs as a default validity time for
3463         /// invoices when no timeout is set.
3464         ///
3465         /// Note that we use block header time to time-out pending inbound payments (with some margin
3466         /// to compensate for the inaccuracy of block header timestamps). Thus, in practice we will
3467         /// accept a payment and generate a [`PaymentReceived`] event for some time after the expiry.
3468         /// If you need exact expiry semantics, you should enforce them upon receipt of
3469         /// [`PaymentReceived`].
3470         ///
3471         /// May panic if `invoice_expiry_delta_secs` is greater than one year.
3472         ///
3473         /// Note that invoices generated for inbound payments should have their `min_final_cltv_expiry`
3474         /// set to at least [`MIN_FINAL_CLTV_EXPIRY`].
3475         ///
3476         /// [`create_inbound_payment`]: Self::create_inbound_payment
3477         /// [`PaymentReceived`]: events::Event::PaymentReceived
3478         /// [`PaymentReceived::user_payment_id`]: events::Event::PaymentReceived::user_payment_id
3479         pub fn create_inbound_payment_for_hash(&self, payment_hash: PaymentHash, min_value_msat: Option<u64>, invoice_expiry_delta_secs: u32, user_payment_id: u64) -> Result<PaymentSecret, APIError> {
3480                 self.set_payment_hash_secret_map(payment_hash, None, min_value_msat, invoice_expiry_delta_secs, user_payment_id)
3481         }
3482 }
3483
3484 impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> MessageSendEventsProvider for ChannelManager<Signer, M, T, K, F, L>
3485         where M::Target: chain::Watch<Signer>,
3486         T::Target: BroadcasterInterface,
3487         K::Target: KeysInterface<Signer = Signer>,
3488         F::Target: FeeEstimator,
3489                                 L::Target: Logger,
3490 {
3491         fn get_and_clear_pending_msg_events(&self) -> Vec<MessageSendEvent> {
3492                 //TODO: This behavior should be documented. It's non-intuitive that we query
3493                 // ChannelMonitors when clearing other events.
3494                 self.process_pending_monitor_events();
3495
3496                 let mut ret = Vec::new();
3497                 let mut channel_state = self.channel_state.lock().unwrap();
3498                 mem::swap(&mut ret, &mut channel_state.pending_msg_events);
3499                 ret
3500         }
3501 }
3502
3503 impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> EventsProvider for ChannelManager<Signer, M, T, K, F, L>
3504         where M::Target: chain::Watch<Signer>,
3505         T::Target: BroadcasterInterface,
3506         K::Target: KeysInterface<Signer = Signer>,
3507         F::Target: FeeEstimator,
3508                                 L::Target: Logger,
3509 {
3510         fn get_and_clear_pending_events(&self) -> Vec<Event> {
3511                 //TODO: This behavior should be documented. It's non-intuitive that we query
3512                 // ChannelMonitors when clearing other events.
3513                 self.process_pending_monitor_events();
3514
3515                 let mut ret = Vec::new();
3516                 let mut pending_events = self.pending_events.lock().unwrap();
3517                 mem::swap(&mut ret, &mut *pending_events);
3518                 ret
3519         }
3520 }
3521
3522 impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> chain::Listen for ChannelManager<Signer, M, T, K, F, L>
3523 where
3524         M::Target: chain::Watch<Signer>,
3525         T::Target: BroadcasterInterface,
3526         K::Target: KeysInterface<Signer = Signer>,
3527         F::Target: FeeEstimator,
3528         L::Target: Logger,
3529 {
3530         fn block_connected(&self, block: &Block, height: u32) {
3531                 {
3532                         let best_block = self.best_block.read().unwrap();
3533                         assert_eq!(best_block.block_hash(), block.header.prev_blockhash,
3534                                 "Blocks must be connected in chain-order - the connected header must build on the last connected header");
3535                         assert_eq!(best_block.height(), height - 1,
3536                                 "Blocks must be connected in chain-order - the connected block height must be one greater than the previous height");
3537                 }
3538
3539                 let txdata: Vec<_> = block.txdata.iter().enumerate().collect();
3540                 self.transactions_confirmed(&block.header, &txdata, height);
3541                 self.best_block_updated(&block.header, height);
3542         }
3543
3544         fn block_disconnected(&self, header: &BlockHeader, height: u32) {
3545                 let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
3546                 let new_height = height - 1;
3547                 {
3548                         let mut best_block = self.best_block.write().unwrap();
3549                         assert_eq!(best_block.block_hash(), header.block_hash(),
3550                                 "Blocks must be disconnected in chain-order - the disconnected header must be the last connected header");
3551                         assert_eq!(best_block.height(), height,
3552                                 "Blocks must be disconnected in chain-order - the disconnected block must have the correct height");
3553                         *best_block = BestBlock::new(header.prev_blockhash, new_height)
3554                 }
3555
3556                 self.do_chain_event(Some(new_height), |channel| channel.best_block_updated(new_height, header.time));
3557         }
3558 }
3559
3560 impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> chain::Confirm for ChannelManager<Signer, M, T, K, F, L>
3561 where
3562         M::Target: chain::Watch<Signer>,
3563         T::Target: BroadcasterInterface,
3564         K::Target: KeysInterface<Signer = Signer>,
3565         F::Target: FeeEstimator,
3566         L::Target: Logger,
3567 {
3568         fn transactions_confirmed(&self, header: &BlockHeader, txdata: &TransactionData, height: u32) {
3569                 // Note that we MUST NOT end up calling methods on self.chain_monitor here - we're called
3570                 // during initialization prior to the chain_monitor being fully configured in some cases.
3571                 // See the docs for `ChannelManagerReadArgs` for more.
3572
3573                 let block_hash = header.block_hash();
3574                 log_trace!(self.logger, "{} transactions included in block {} at height {} provided", txdata.len(), block_hash, height);
3575
3576                 let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
3577                 self.do_chain_event(Some(height), |channel| channel.transactions_confirmed(&block_hash, height, txdata, &self.logger).map(|a| (a, Vec::new())));
3578         }
3579
3580         fn best_block_updated(&self, header: &BlockHeader, height: u32) {
3581                 // Note that we MUST NOT end up calling methods on self.chain_monitor here - we're called
3582                 // during initialization prior to the chain_monitor being fully configured in some cases.
3583                 // See the docs for `ChannelManagerReadArgs` for more.
3584
3585                 let block_hash = header.block_hash();
3586                 log_trace!(self.logger, "New best block: {} at height {}", block_hash, height);
3587
3588                 let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
3589
3590                 *self.best_block.write().unwrap() = BestBlock::new(block_hash, height);
3591
3592                 self.do_chain_event(Some(height), |channel| channel.best_block_updated(height, header.time));
3593
3594                 macro_rules! max_time {
3595                         ($timestamp: expr) => {
3596                                 loop {
3597                                         // Update $timestamp to be the max of its current value and the block
3598                                         // timestamp. This should keep us close to the current time without relying on
3599                                         // having an explicit local time source.
3600                                         // Just in case we end up in a race, we loop until we either successfully
3601                                         // update $timestamp or decide we don't need to.
3602                                         let old_serial = $timestamp.load(Ordering::Acquire);
3603                                         if old_serial >= header.time as usize { break; }
3604                                         if $timestamp.compare_exchange(old_serial, header.time as usize, Ordering::AcqRel, Ordering::Relaxed).is_ok() {
3605                                                 break;
3606                                         }
3607                                 }
3608                         }
3609                 }
3610                 max_time!(self.last_node_announcement_serial);
3611                 max_time!(self.highest_seen_timestamp);
3612                 let mut payment_secrets = self.pending_inbound_payments.lock().unwrap();
3613                 payment_secrets.retain(|_, inbound_payment| {
3614                         inbound_payment.expiry_time > header.time as u64
3615                 });
3616         }
3617
3618         fn get_relevant_txids(&self) -> Vec<Txid> {
3619                 let channel_state = self.channel_state.lock().unwrap();
3620                 let mut res = Vec::with_capacity(channel_state.short_to_id.len());
3621                 for chan in channel_state.by_id.values() {
3622                         if let Some(funding_txo) = chan.get_funding_txo() {
3623                                 res.push(funding_txo.txid);
3624                         }
3625                 }
3626                 res
3627         }
3628
3629         fn transaction_unconfirmed(&self, txid: &Txid) {
3630                 let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
3631                 self.do_chain_event(None, |channel| {
3632                         if let Some(funding_txo) = channel.get_funding_txo() {
3633                                 if funding_txo.txid == *txid {
3634                                         channel.funding_transaction_unconfirmed().map(|_| (None, Vec::new()))
3635                                 } else { Ok((None, Vec::new())) }
3636                         } else { Ok((None, Vec::new())) }
3637                 });
3638         }
3639 }
3640
3641 impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelManager<Signer, M, T, K, F, L>
3642 where
3643         M::Target: chain::Watch<Signer>,
3644         T::Target: BroadcasterInterface,
3645         K::Target: KeysInterface<Signer = Signer>,
3646         F::Target: FeeEstimator,
3647         L::Target: Logger,
3648 {
3649         /// Calls a function which handles an on-chain event (blocks dis/connected, transactions
3650         /// un/confirmed, etc) on each channel, handling any resulting errors or messages generated by
3651         /// the function.
3652         fn do_chain_event<FN: Fn(&mut Channel<Signer>) -> Result<(Option<msgs::FundingLocked>, Vec<(HTLCSource, PaymentHash)>), msgs::ErrorMessage>>
3653                         (&self, height_opt: Option<u32>, f: FN) {
3654                 // Note that we MUST NOT end up calling methods on self.chain_monitor here - we're called
3655                 // during initialization prior to the chain_monitor being fully configured in some cases.
3656                 // See the docs for `ChannelManagerReadArgs` for more.
3657
3658                 let mut failed_channels = Vec::new();
3659                 let mut timed_out_htlcs = Vec::new();
3660                 {
3661                         let mut channel_lock = self.channel_state.lock().unwrap();
3662                         let channel_state = &mut *channel_lock;
3663                         let short_to_id = &mut channel_state.short_to_id;
3664                         let pending_msg_events = &mut channel_state.pending_msg_events;
3665                         channel_state.by_id.retain(|_, channel| {
3666                                 let res = f(channel);
3667                                 if let Ok((chan_res, mut timed_out_pending_htlcs)) = res {
3668                                         for (source, payment_hash) in timed_out_pending_htlcs.drain(..) {
3669                                                 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
3670                                                 timed_out_htlcs.push((source, payment_hash,  HTLCFailReason::Reason {
3671                                                         failure_code: 0x1000 | 14, // expiry_too_soon, or at least it is now
3672                                                         data: chan_update,
3673                                                 }));
3674                                         }
3675                                         if let Some(funding_locked) = chan_res {
3676                                                 pending_msg_events.push(events::MessageSendEvent::SendFundingLocked {
3677                                                         node_id: channel.get_counterparty_node_id(),
3678                                                         msg: funding_locked,
3679                                                 });
3680                                                 if let Some(announcement_sigs) = self.get_announcement_sigs(channel) {
3681                                                         log_trace!(self.logger, "Sending funding_locked and announcement_signatures for {}", log_bytes!(channel.channel_id()));
3682                                                         pending_msg_events.push(events::MessageSendEvent::SendAnnouncementSignatures {
3683                                                                 node_id: channel.get_counterparty_node_id(),
3684                                                                 msg: announcement_sigs,
3685                                                         });
3686                                                 } else {
3687                                                         log_trace!(self.logger, "Sending funding_locked WITHOUT announcement_signatures for {}", log_bytes!(channel.channel_id()));
3688                                                 }
3689                                                 short_to_id.insert(channel.get_short_channel_id().unwrap(), channel.channel_id());
3690                                         }
3691                                 } else if let Err(e) = res {
3692                                         if let Some(short_id) = channel.get_short_channel_id() {
3693                                                 short_to_id.remove(&short_id);
3694                                         }
3695                                         // It looks like our counterparty went on-chain or funding transaction was
3696                                         // reorged out of the main chain. Close the channel.
3697                                         failed_channels.push(channel.force_shutdown(true));
3698                                         if let Ok(update) = self.get_channel_update(&channel) {
3699                                                 pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
3700                                                         msg: update
3701                                                 });
3702                                         }
3703                                         pending_msg_events.push(events::MessageSendEvent::HandleError {
3704                                                 node_id: channel.get_counterparty_node_id(),
3705                                                 action: msgs::ErrorAction::SendErrorMessage { msg: e },
3706                                         });
3707                                         return false;
3708                                 }
3709                                 true
3710                         });
3711
3712                         if let Some(height) = height_opt {
3713                                 channel_state.claimable_htlcs.retain(|payment_hash, htlcs| {
3714                                         htlcs.retain(|htlc| {
3715                                                 // If height is approaching the number of blocks we think it takes us to get
3716                                                 // our commitment transaction confirmed before the HTLC expires, plus the
3717                                                 // number of blocks we generally consider it to take to do a commitment update,
3718                                                 // just give up on it and fail the HTLC.
3719                                                 if height >= htlc.cltv_expiry - HTLC_FAIL_BACK_BUFFER {
3720                                                         let mut htlc_msat_height_data = byte_utils::be64_to_array(htlc.value).to_vec();
3721                                                         htlc_msat_height_data.extend_from_slice(&byte_utils::be32_to_array(height));
3722                                                         timed_out_htlcs.push((HTLCSource::PreviousHopData(htlc.prev_hop.clone()), payment_hash.clone(), HTLCFailReason::Reason {
3723                                                                 failure_code: 0x4000 | 15,
3724                                                                 data: htlc_msat_height_data
3725                                                         }));
3726                                                         false
3727                                                 } else { true }
3728                                         });
3729                                         !htlcs.is_empty() // Only retain this entry if htlcs has at least one entry.
3730                                 });
3731                         }
3732                 }
3733
3734                 self.handle_init_event_channel_failures(failed_channels);
3735
3736                 for (source, payment_hash, reason) in timed_out_htlcs.drain(..) {
3737                         self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), source, &payment_hash, reason);
3738                 }
3739         }
3740
3741         /// Blocks until ChannelManager needs to be persisted or a timeout is reached. It returns a bool
3742         /// indicating whether persistence is necessary. Only one listener on
3743         /// `await_persistable_update` or `await_persistable_update_timeout` is guaranteed to be woken
3744         /// up.
3745         /// Note that the feature `allow_wallclock_use` must be enabled to use this function.
3746         #[cfg(any(test, feature = "allow_wallclock_use"))]
3747         pub fn await_persistable_update_timeout(&self, max_wait: Duration) -> bool {
3748                 self.persistence_notifier.wait_timeout(max_wait)
3749         }
3750
3751         /// Blocks until ChannelManager needs to be persisted. Only one listener on
3752         /// `await_persistable_update` or `await_persistable_update_timeout` is guaranteed to be woken
3753         /// up.
3754         pub fn await_persistable_update(&self) {
3755                 self.persistence_notifier.wait()
3756         }
3757
3758         #[cfg(any(test, feature = "_test_utils"))]
3759         pub fn get_persistence_condvar_value(&self) -> bool {
3760                 let mutcond = &self.persistence_notifier.persistence_lock;
3761                 let &(ref mtx, _) = mutcond;
3762                 let guard = mtx.lock().unwrap();
3763                 *guard
3764         }
3765 }
3766
3767 impl<Signer: Sign, M: Deref + Sync + Send, T: Deref + Sync + Send, K: Deref + Sync + Send, F: Deref + Sync + Send, L: Deref + Sync + Send>
3768         ChannelMessageHandler for ChannelManager<Signer, M, T, K, F, L>
3769         where M::Target: chain::Watch<Signer>,
3770         T::Target: BroadcasterInterface,
3771         K::Target: KeysInterface<Signer = Signer>,
3772         F::Target: FeeEstimator,
3773         L::Target: Logger,
3774 {
3775         fn handle_open_channel(&self, counterparty_node_id: &PublicKey, their_features: InitFeatures, msg: &msgs::OpenChannel) {
3776                 let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
3777                 let _ = handle_error!(self, self.internal_open_channel(counterparty_node_id, their_features, msg), *counterparty_node_id);
3778         }
3779
3780         fn handle_accept_channel(&self, counterparty_node_id: &PublicKey, their_features: InitFeatures, msg: &msgs::AcceptChannel) {
3781                 let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
3782                 let _ = handle_error!(self, self.internal_accept_channel(counterparty_node_id, their_features, msg), *counterparty_node_id);
3783         }
3784
3785         fn handle_funding_created(&self, counterparty_node_id: &PublicKey, msg: &msgs::FundingCreated) {
3786                 let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
3787                 let _ = handle_error!(self, self.internal_funding_created(counterparty_node_id, msg), *counterparty_node_id);
3788         }
3789
3790         fn handle_funding_signed(&self, counterparty_node_id: &PublicKey, msg: &msgs::FundingSigned) {
3791                 let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
3792                 let _ = handle_error!(self, self.internal_funding_signed(counterparty_node_id, msg), *counterparty_node_id);
3793         }
3794
3795         fn handle_funding_locked(&self, counterparty_node_id: &PublicKey, msg: &msgs::FundingLocked) {
3796                 let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
3797                 let _ = handle_error!(self, self.internal_funding_locked(counterparty_node_id, msg), *counterparty_node_id);
3798         }
3799
3800         fn handle_shutdown(&self, counterparty_node_id: &PublicKey, their_features: &InitFeatures, msg: &msgs::Shutdown) {
3801                 let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
3802                 let _ = handle_error!(self, self.internal_shutdown(counterparty_node_id, their_features, msg), *counterparty_node_id);
3803         }
3804
3805         fn handle_closing_signed(&self, counterparty_node_id: &PublicKey, msg: &msgs::ClosingSigned) {
3806                 let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
3807                 let _ = handle_error!(self, self.internal_closing_signed(counterparty_node_id, msg), *counterparty_node_id);
3808         }
3809
3810         fn handle_update_add_htlc(&self, counterparty_node_id: &PublicKey, msg: &msgs::UpdateAddHTLC) {
3811                 let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
3812                 let _ = handle_error!(self, self.internal_update_add_htlc(counterparty_node_id, msg), *counterparty_node_id);
3813         }
3814
3815         fn handle_update_fulfill_htlc(&self, counterparty_node_id: &PublicKey, msg: &msgs::UpdateFulfillHTLC) {
3816                 let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
3817                 let _ = handle_error!(self, self.internal_update_fulfill_htlc(counterparty_node_id, msg), *counterparty_node_id);
3818         }
3819
3820         fn handle_update_fail_htlc(&self, counterparty_node_id: &PublicKey, msg: &msgs::UpdateFailHTLC) {
3821                 let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
3822                 let _ = handle_error!(self, self.internal_update_fail_htlc(counterparty_node_id, msg), *counterparty_node_id);
3823         }
3824
3825         fn handle_update_fail_malformed_htlc(&self, counterparty_node_id: &PublicKey, msg: &msgs::UpdateFailMalformedHTLC) {
3826                 let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
3827                 let _ = handle_error!(self, self.internal_update_fail_malformed_htlc(counterparty_node_id, msg), *counterparty_node_id);
3828         }
3829
3830         fn handle_commitment_signed(&self, counterparty_node_id: &PublicKey, msg: &msgs::CommitmentSigned) {
3831                 let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
3832                 let _ = handle_error!(self, self.internal_commitment_signed(counterparty_node_id, msg), *counterparty_node_id);
3833         }
3834
3835         fn handle_revoke_and_ack(&self, counterparty_node_id: &PublicKey, msg: &msgs::RevokeAndACK) {
3836                 let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
3837                 let _ = handle_error!(self, self.internal_revoke_and_ack(counterparty_node_id, msg), *counterparty_node_id);
3838         }
3839
3840         fn handle_update_fee(&self, counterparty_node_id: &PublicKey, msg: &msgs::UpdateFee) {
3841                 let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
3842                 let _ = handle_error!(self, self.internal_update_fee(counterparty_node_id, msg), *counterparty_node_id);
3843         }
3844
3845         fn handle_announcement_signatures(&self, counterparty_node_id: &PublicKey, msg: &msgs::AnnouncementSignatures) {
3846                 let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
3847                 let _ = handle_error!(self, self.internal_announcement_signatures(counterparty_node_id, msg), *counterparty_node_id);
3848         }
3849
3850         fn handle_channel_update(&self, counterparty_node_id: &PublicKey, msg: &msgs::ChannelUpdate) {
3851                 let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
3852                 let _ = handle_error!(self, self.internal_channel_update(counterparty_node_id, msg), *counterparty_node_id);
3853         }
3854
3855         fn handle_channel_reestablish(&self, counterparty_node_id: &PublicKey, msg: &msgs::ChannelReestablish) {
3856                 let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
3857                 let _ = handle_error!(self, self.internal_channel_reestablish(counterparty_node_id, msg), *counterparty_node_id);
3858         }
3859
3860         fn peer_disconnected(&self, counterparty_node_id: &PublicKey, no_connection_possible: bool) {
3861                 let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
3862                 let mut failed_channels = Vec::new();
3863                 let mut failed_payments = Vec::new();
3864                 let mut no_channels_remain = true;
3865                 {
3866                         let mut channel_state_lock = self.channel_state.lock().unwrap();
3867                         let channel_state = &mut *channel_state_lock;
3868                         let short_to_id = &mut channel_state.short_to_id;
3869                         let pending_msg_events = &mut channel_state.pending_msg_events;
3870                         if no_connection_possible {
3871                                 log_debug!(self.logger, "Failing all channels with {} due to no_connection_possible", log_pubkey!(counterparty_node_id));
3872                                 channel_state.by_id.retain(|_, chan| {
3873                                         if chan.get_counterparty_node_id() == *counterparty_node_id {
3874                                                 if let Some(short_id) = chan.get_short_channel_id() {
3875                                                         short_to_id.remove(&short_id);
3876                                                 }
3877                                                 failed_channels.push(chan.force_shutdown(true));
3878                                                 if let Ok(update) = self.get_channel_update(&chan) {
3879                                                         pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
3880                                                                 msg: update
3881                                                         });
3882                                                 }
3883                                                 false
3884                                         } else {
3885                                                 true
3886                                         }
3887                                 });
3888                         } else {
3889                                 log_debug!(self.logger, "Marking channels with {} disconnected and generating channel_updates", log_pubkey!(counterparty_node_id));
3890                                 channel_state.by_id.retain(|_, chan| {
3891                                         if chan.get_counterparty_node_id() == *counterparty_node_id {
3892                                                 // Note that currently on channel reestablish we assert that there are no
3893                                                 // holding cell add-HTLCs, so if in the future we stop removing uncommitted HTLCs
3894                                                 // on peer disconnect here, there will need to be corresponding changes in
3895                                                 // reestablish logic.
3896                                                 let failed_adds = chan.remove_uncommitted_htlcs_and_mark_paused(&self.logger);
3897                                                 chan.to_disabled_marked();
3898                                                 if !failed_adds.is_empty() {
3899                                                         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
3900                                                         failed_payments.push((chan_update, failed_adds));
3901                                                 }
3902                                                 if chan.is_shutdown() {
3903                                                         if let Some(short_id) = chan.get_short_channel_id() {
3904                                                                 short_to_id.remove(&short_id);
3905                                                         }
3906                                                         return false;
3907                                                 } else {
3908                                                         no_channels_remain = false;
3909                                                 }
3910                                         }
3911                                         true
3912                                 })
3913                         }
3914                         pending_msg_events.retain(|msg| {
3915                                 match msg {
3916                                         &events::MessageSendEvent::SendAcceptChannel { ref node_id, .. } => node_id != counterparty_node_id,
3917                                         &events::MessageSendEvent::SendOpenChannel { ref node_id, .. } => node_id != counterparty_node_id,
3918                                         &events::MessageSendEvent::SendFundingCreated { ref node_id, .. } => node_id != counterparty_node_id,
3919                                         &events::MessageSendEvent::SendFundingSigned { ref node_id, .. } => node_id != counterparty_node_id,
3920                                         &events::MessageSendEvent::SendFundingLocked { ref node_id, .. } => node_id != counterparty_node_id,
3921                                         &events::MessageSendEvent::SendAnnouncementSignatures { ref node_id, .. } => node_id != counterparty_node_id,
3922                                         &events::MessageSendEvent::UpdateHTLCs { ref node_id, .. } => node_id != counterparty_node_id,
3923                                         &events::MessageSendEvent::SendRevokeAndACK { ref node_id, .. } => node_id != counterparty_node_id,
3924                                         &events::MessageSendEvent::SendClosingSigned { ref node_id, .. } => node_id != counterparty_node_id,
3925                                         &events::MessageSendEvent::SendShutdown { ref node_id, .. } => node_id != counterparty_node_id,
3926                                         &events::MessageSendEvent::SendChannelReestablish { ref node_id, .. } => node_id != counterparty_node_id,
3927                                         &events::MessageSendEvent::BroadcastChannelAnnouncement { .. } => true,
3928                                         &events::MessageSendEvent::BroadcastNodeAnnouncement { .. } => true,
3929                                         &events::MessageSendEvent::BroadcastChannelUpdate { .. } => true,
3930                                         &events::MessageSendEvent::HandleError { ref node_id, .. } => node_id != counterparty_node_id,
3931                                         &events::MessageSendEvent::PaymentFailureNetworkUpdate { .. } => true,
3932                                         &events::MessageSendEvent::SendChannelRangeQuery { .. } => false,
3933                                         &events::MessageSendEvent::SendShortIdsQuery { .. } => false,
3934                                         &events::MessageSendEvent::SendReplyChannelRange { .. } => false,
3935                                 }
3936                         });
3937                 }
3938                 if no_channels_remain {
3939                         self.per_peer_state.write().unwrap().remove(counterparty_node_id);
3940                 }
3941
3942                 for failure in failed_channels.drain(..) {
3943                         self.finish_force_close_channel(failure);
3944                 }
3945                 for (chan_update, mut htlc_sources) in failed_payments {
3946                         for (htlc_source, payment_hash) in htlc_sources.drain(..) {
3947                                 self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), htlc_source, &payment_hash, HTLCFailReason::Reason { failure_code: 0x1000 | 7, data: chan_update.clone() });
3948                         }
3949                 }
3950         }
3951
3952         fn peer_connected(&self, counterparty_node_id: &PublicKey, init_msg: &msgs::Init) {
3953                 log_debug!(self.logger, "Generating channel_reestablish events for {}", log_pubkey!(counterparty_node_id));
3954
3955                 let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
3956
3957                 {
3958                         let mut peer_state_lock = self.per_peer_state.write().unwrap();
3959                         match peer_state_lock.entry(counterparty_node_id.clone()) {
3960                                 hash_map::Entry::Vacant(e) => {
3961                                         e.insert(Mutex::new(PeerState {
3962                                                 latest_features: init_msg.features.clone(),
3963                                         }));
3964                                 },
3965                                 hash_map::Entry::Occupied(e) => {
3966                                         e.get().lock().unwrap().latest_features = init_msg.features.clone();
3967                                 },
3968                         }
3969                 }
3970
3971                 let mut channel_state_lock = self.channel_state.lock().unwrap();
3972                 let channel_state = &mut *channel_state_lock;
3973                 let pending_msg_events = &mut channel_state.pending_msg_events;
3974                 channel_state.by_id.retain(|_, chan| {
3975                         if chan.get_counterparty_node_id() == *counterparty_node_id {
3976                                 if !chan.have_received_message() {
3977                                         // If we created this (outbound) channel while we were disconnected from the
3978                                         // peer we probably failed to send the open_channel message, which is now
3979                                         // lost. We can't have had anything pending related to this channel, so we just
3980                                         // drop it.
3981                                         false
3982                                 } else {
3983                                         pending_msg_events.push(events::MessageSendEvent::SendChannelReestablish {
3984                                                 node_id: chan.get_counterparty_node_id(),
3985                                                 msg: chan.get_channel_reestablish(&self.logger),
3986                                         });
3987                                         true
3988                                 }
3989                         } else { true }
3990                 });
3991                 //TODO: Also re-broadcast announcement_signatures
3992         }
3993
3994         fn handle_error(&self, counterparty_node_id: &PublicKey, msg: &msgs::ErrorMessage) {
3995                 let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
3996
3997                 if msg.channel_id == [0; 32] {
3998                         for chan in self.list_channels() {
3999                                 if chan.remote_network_id == *counterparty_node_id {
4000                                         // Untrusted messages from peer, we throw away the error if id points to a non-existent channel
4001                                         let _ = self.force_close_channel_with_peer(&chan.channel_id, Some(counterparty_node_id));
4002                                 }
4003                         }
4004                 } else {
4005                         // Untrusted messages from peer, we throw away the error if id points to a non-existent channel
4006                         let _ = self.force_close_channel_with_peer(&msg.channel_id, Some(counterparty_node_id));
4007                 }
4008         }
4009 }
4010
4011 /// Used to signal to the ChannelManager persister that the manager needs to be re-persisted to
4012 /// disk/backups, through `await_persistable_update_timeout` and `await_persistable_update`.
4013 struct PersistenceNotifier {
4014         /// Users won't access the persistence_lock directly, but rather wait on its bool using
4015         /// `wait_timeout` and `wait`.
4016         persistence_lock: (Mutex<bool>, Condvar),
4017 }
4018
4019 impl PersistenceNotifier {
4020         fn new() -> Self {
4021                 Self {
4022                         persistence_lock: (Mutex::new(false), Condvar::new()),
4023                 }
4024         }
4025
4026         fn wait(&self) {
4027                 loop {
4028                         let &(ref mtx, ref cvar) = &self.persistence_lock;
4029                         let mut guard = mtx.lock().unwrap();
4030                         guard = cvar.wait(guard).unwrap();
4031                         let result = *guard;
4032                         if result {
4033                                 *guard = false;
4034                                 return
4035                         }
4036                 }
4037         }
4038
4039         #[cfg(any(test, feature = "allow_wallclock_use"))]
4040         fn wait_timeout(&self, max_wait: Duration) -> bool {
4041                 let current_time = Instant::now();
4042                 loop {
4043                         let &(ref mtx, ref cvar) = &self.persistence_lock;
4044                         let mut guard = mtx.lock().unwrap();
4045                         guard = cvar.wait_timeout(guard, max_wait).unwrap().0;
4046                         // Due to spurious wakeups that can happen on `wait_timeout`, here we need to check if the
4047                         // desired wait time has actually passed, and if not then restart the loop with a reduced wait
4048                         // time. Note that this logic can be highly simplified through the use of
4049                         // `Condvar::wait_while` and `Condvar::wait_timeout_while`, if and when our MSRV is raised to
4050                         // 1.42.0.
4051                         let elapsed = current_time.elapsed();
4052                         let result = *guard;
4053                         if result || elapsed >= max_wait {
4054                                 *guard = false;
4055                                 return result;
4056                         }
4057                         match max_wait.checked_sub(elapsed) {
4058                                 None => return result,
4059                                 Some(_) => continue
4060                         }
4061                 }
4062         }
4063
4064         // Signal to the ChannelManager persister that there are updates necessitating persisting to disk.
4065         fn notify(&self) {
4066                 let &(ref persist_mtx, ref cnd) = &self.persistence_lock;
4067                 let mut persistence_lock = persist_mtx.lock().unwrap();
4068                 *persistence_lock = true;
4069                 mem::drop(persistence_lock);
4070                 cnd.notify_all();
4071         }
4072 }
4073
4074 const SERIALIZATION_VERSION: u8 = 1;
4075 const MIN_SERIALIZATION_VERSION: u8 = 1;
4076
4077 impl Writeable for PendingHTLCInfo {
4078         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
4079                 match &self.routing {
4080                         &PendingHTLCRouting::Forward { ref onion_packet, ref short_channel_id } => {
4081                                 0u8.write(writer)?;
4082                                 onion_packet.write(writer)?;
4083                                 short_channel_id.write(writer)?;
4084                         },
4085                         &PendingHTLCRouting::Receive { ref payment_data, ref incoming_cltv_expiry } => {
4086                                 1u8.write(writer)?;
4087                                 payment_data.payment_secret.write(writer)?;
4088                                 payment_data.total_msat.write(writer)?;
4089                                 incoming_cltv_expiry.write(writer)?;
4090                         },
4091                 }
4092                 self.incoming_shared_secret.write(writer)?;
4093                 self.payment_hash.write(writer)?;
4094                 self.amt_to_forward.write(writer)?;
4095                 self.outgoing_cltv_value.write(writer)?;
4096                 Ok(())
4097         }
4098 }
4099
4100 impl Readable for PendingHTLCInfo {
4101         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<PendingHTLCInfo, DecodeError> {
4102                 Ok(PendingHTLCInfo {
4103                         routing: match Readable::read(reader)? {
4104                                 0u8 => PendingHTLCRouting::Forward {
4105                                         onion_packet: Readable::read(reader)?,
4106                                         short_channel_id: Readable::read(reader)?,
4107                                 },
4108                                 1u8 => PendingHTLCRouting::Receive {
4109                                         payment_data: msgs::FinalOnionHopData {
4110                                                 payment_secret: Readable::read(reader)?,
4111                                                 total_msat: Readable::read(reader)?,
4112                                         },
4113                                         incoming_cltv_expiry: Readable::read(reader)?,
4114                                 },
4115                                 _ => return Err(DecodeError::InvalidValue),
4116                         },
4117                         incoming_shared_secret: Readable::read(reader)?,
4118                         payment_hash: Readable::read(reader)?,
4119                         amt_to_forward: Readable::read(reader)?,
4120                         outgoing_cltv_value: Readable::read(reader)?,
4121                 })
4122         }
4123 }
4124
4125 impl Writeable for HTLCFailureMsg {
4126         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
4127                 match self {
4128                         &HTLCFailureMsg::Relay(ref fail_msg) => {
4129                                 0u8.write(writer)?;
4130                                 fail_msg.write(writer)?;
4131                         },
4132                         &HTLCFailureMsg::Malformed(ref fail_msg) => {
4133                                 1u8.write(writer)?;
4134                                 fail_msg.write(writer)?;
4135                         }
4136                 }
4137                 Ok(())
4138         }
4139 }
4140
4141 impl Readable for HTLCFailureMsg {
4142         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<HTLCFailureMsg, DecodeError> {
4143                 match <u8 as Readable>::read(reader)? {
4144                         0 => Ok(HTLCFailureMsg::Relay(Readable::read(reader)?)),
4145                         1 => Ok(HTLCFailureMsg::Malformed(Readable::read(reader)?)),
4146                         _ => Err(DecodeError::InvalidValue),
4147                 }
4148         }
4149 }
4150
4151 impl Writeable for PendingHTLCStatus {
4152         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
4153                 match self {
4154                         &PendingHTLCStatus::Forward(ref forward_info) => {
4155                                 0u8.write(writer)?;
4156                                 forward_info.write(writer)?;
4157                         },
4158                         &PendingHTLCStatus::Fail(ref fail_msg) => {
4159                                 1u8.write(writer)?;
4160                                 fail_msg.write(writer)?;
4161                         }
4162                 }
4163                 Ok(())
4164         }
4165 }
4166
4167 impl Readable for PendingHTLCStatus {
4168         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<PendingHTLCStatus, DecodeError> {
4169                 match <u8 as Readable>::read(reader)? {
4170                         0 => Ok(PendingHTLCStatus::Forward(Readable::read(reader)?)),
4171                         1 => Ok(PendingHTLCStatus::Fail(Readable::read(reader)?)),
4172                         _ => Err(DecodeError::InvalidValue),
4173                 }
4174         }
4175 }
4176
4177 impl_writeable!(HTLCPreviousHopData, 0, {
4178         short_channel_id,
4179         outpoint,
4180         htlc_id,
4181         incoming_packet_shared_secret
4182 });
4183
4184 impl Writeable for ClaimableHTLC {
4185         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
4186                 self.prev_hop.write(writer)?;
4187                 self.value.write(writer)?;
4188                 self.payment_data.payment_secret.write(writer)?;
4189                 self.payment_data.total_msat.write(writer)?;
4190                 self.cltv_expiry.write(writer)
4191         }
4192 }
4193
4194 impl Readable for ClaimableHTLC {
4195         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
4196                 Ok(ClaimableHTLC {
4197                         prev_hop: Readable::read(reader)?,
4198                         value: Readable::read(reader)?,
4199                         payment_data: msgs::FinalOnionHopData {
4200                                 payment_secret: Readable::read(reader)?,
4201                                 total_msat: Readable::read(reader)?,
4202                         },
4203                         cltv_expiry: Readable::read(reader)?,
4204                 })
4205         }
4206 }
4207
4208 impl Writeable for HTLCSource {
4209         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
4210                 match self {
4211                         &HTLCSource::PreviousHopData(ref hop_data) => {
4212                                 0u8.write(writer)?;
4213                                 hop_data.write(writer)?;
4214                         },
4215                         &HTLCSource::OutboundRoute { ref path, ref session_priv, ref first_hop_htlc_msat } => {
4216                                 1u8.write(writer)?;
4217                                 path.write(writer)?;
4218                                 session_priv.write(writer)?;
4219                                 first_hop_htlc_msat.write(writer)?;
4220                         }
4221                 }
4222                 Ok(())
4223         }
4224 }
4225
4226 impl Readable for HTLCSource {
4227         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<HTLCSource, DecodeError> {
4228                 match <u8 as Readable>::read(reader)? {
4229                         0 => Ok(HTLCSource::PreviousHopData(Readable::read(reader)?)),
4230                         1 => Ok(HTLCSource::OutboundRoute {
4231                                 path: Readable::read(reader)?,
4232                                 session_priv: Readable::read(reader)?,
4233                                 first_hop_htlc_msat: Readable::read(reader)?,
4234                         }),
4235                         _ => Err(DecodeError::InvalidValue),
4236                 }
4237         }
4238 }
4239
4240 impl Writeable for HTLCFailReason {
4241         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
4242                 match self {
4243                         &HTLCFailReason::LightningError { ref err } => {
4244                                 0u8.write(writer)?;
4245                                 err.write(writer)?;
4246                         },
4247                         &HTLCFailReason::Reason { ref failure_code, ref data } => {
4248                                 1u8.write(writer)?;
4249                                 failure_code.write(writer)?;
4250                                 data.write(writer)?;
4251                         }
4252                 }
4253                 Ok(())
4254         }
4255 }
4256
4257 impl Readable for HTLCFailReason {
4258         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<HTLCFailReason, DecodeError> {
4259                 match <u8 as Readable>::read(reader)? {
4260                         0 => Ok(HTLCFailReason::LightningError { err: Readable::read(reader)? }),
4261                         1 => Ok(HTLCFailReason::Reason {
4262                                 failure_code: Readable::read(reader)?,
4263                                 data: Readable::read(reader)?,
4264                         }),
4265                         _ => Err(DecodeError::InvalidValue),
4266                 }
4267         }
4268 }
4269
4270 impl Writeable for HTLCForwardInfo {
4271         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
4272                 match self {
4273                         &HTLCForwardInfo::AddHTLC { ref prev_short_channel_id, ref prev_funding_outpoint, ref prev_htlc_id, ref forward_info } => {
4274                                 0u8.write(writer)?;
4275                                 prev_short_channel_id.write(writer)?;
4276                                 prev_funding_outpoint.write(writer)?;
4277                                 prev_htlc_id.write(writer)?;
4278                                 forward_info.write(writer)?;
4279                         },
4280                         &HTLCForwardInfo::FailHTLC { ref htlc_id, ref err_packet } => {
4281                                 1u8.write(writer)?;
4282                                 htlc_id.write(writer)?;
4283                                 err_packet.write(writer)?;
4284                         },
4285                 }
4286                 Ok(())
4287         }
4288 }
4289
4290 impl Readable for HTLCForwardInfo {
4291         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<HTLCForwardInfo, DecodeError> {
4292                 match <u8 as Readable>::read(reader)? {
4293                         0 => Ok(HTLCForwardInfo::AddHTLC {
4294                                 prev_short_channel_id: Readable::read(reader)?,
4295                                 prev_funding_outpoint: Readable::read(reader)?,
4296                                 prev_htlc_id: Readable::read(reader)?,
4297                                 forward_info: Readable::read(reader)?,
4298                         }),
4299                         1 => Ok(HTLCForwardInfo::FailHTLC {
4300                                 htlc_id: Readable::read(reader)?,
4301                                 err_packet: Readable::read(reader)?,
4302                         }),
4303                         _ => Err(DecodeError::InvalidValue),
4304                 }
4305         }
4306 }
4307
4308 impl_writeable!(PendingInboundPayment, 0, {
4309         payment_secret,
4310         expiry_time,
4311         user_payment_id,
4312         payment_preimage,
4313         min_value_msat
4314 });
4315
4316 impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> Writeable for ChannelManager<Signer, M, T, K, F, L>
4317         where M::Target: chain::Watch<Signer>,
4318         T::Target: BroadcasterInterface,
4319         K::Target: KeysInterface<Signer = Signer>,
4320         F::Target: FeeEstimator,
4321         L::Target: Logger,
4322 {
4323         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
4324                 let _consistency_lock = self.total_consistency_lock.write().unwrap();
4325
4326                 writer.write_all(&[SERIALIZATION_VERSION; 1])?;
4327                 writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
4328
4329                 self.genesis_hash.write(writer)?;
4330                 {
4331                         let best_block = self.best_block.read().unwrap();
4332                         best_block.height().write(writer)?;
4333                         best_block.block_hash().write(writer)?;
4334                 }
4335
4336                 let channel_state = self.channel_state.lock().unwrap();
4337                 let mut unfunded_channels = 0;
4338                 for (_, channel) in channel_state.by_id.iter() {
4339                         if !channel.is_funding_initiated() {
4340                                 unfunded_channels += 1;
4341                         }
4342                 }
4343                 ((channel_state.by_id.len() - unfunded_channels) as u64).write(writer)?;
4344                 for (_, channel) in channel_state.by_id.iter() {
4345                         if channel.is_funding_initiated() {
4346                                 channel.write(writer)?;
4347                         }
4348                 }
4349
4350                 (channel_state.forward_htlcs.len() as u64).write(writer)?;
4351                 for (short_channel_id, pending_forwards) in channel_state.forward_htlcs.iter() {
4352                         short_channel_id.write(writer)?;
4353                         (pending_forwards.len() as u64).write(writer)?;
4354                         for forward in pending_forwards {
4355                                 forward.write(writer)?;
4356                         }
4357                 }
4358
4359                 (channel_state.claimable_htlcs.len() as u64).write(writer)?;
4360                 for (payment_hash, previous_hops) in channel_state.claimable_htlcs.iter() {
4361                         payment_hash.write(writer)?;
4362                         (previous_hops.len() as u64).write(writer)?;
4363                         for htlc in previous_hops.iter() {
4364                                 htlc.write(writer)?;
4365                         }
4366                 }
4367
4368                 let per_peer_state = self.per_peer_state.write().unwrap();
4369                 (per_peer_state.len() as u64).write(writer)?;
4370                 for (peer_pubkey, peer_state_mutex) in per_peer_state.iter() {
4371                         peer_pubkey.write(writer)?;
4372                         let peer_state = peer_state_mutex.lock().unwrap();
4373                         peer_state.latest_features.write(writer)?;
4374                 }
4375
4376                 let events = self.pending_events.lock().unwrap();
4377                 (events.len() as u64).write(writer)?;
4378                 for event in events.iter() {
4379                         event.write(writer)?;
4380                 }
4381
4382                 let background_events = self.pending_background_events.lock().unwrap();
4383                 (background_events.len() as u64).write(writer)?;
4384                 for event in background_events.iter() {
4385                         match event {
4386                                 BackgroundEvent::ClosingMonitorUpdate((funding_txo, monitor_update)) => {
4387                                         0u8.write(writer)?;
4388                                         funding_txo.write(writer)?;
4389                                         monitor_update.write(writer)?;
4390                                 },
4391                         }
4392                 }
4393
4394                 (self.last_node_announcement_serial.load(Ordering::Acquire) as u32).write(writer)?;
4395                 (self.highest_seen_timestamp.load(Ordering::Acquire) as u32).write(writer)?;
4396
4397                 let pending_inbound_payments = self.pending_inbound_payments.lock().unwrap();
4398                 (pending_inbound_payments.len() as u64).write(writer)?;
4399                 for (hash, pending_payment) in pending_inbound_payments.iter() {
4400                         hash.write(writer)?;
4401                         pending_payment.write(writer)?;
4402                 }
4403
4404                 Ok(())
4405         }
4406 }
4407
4408 /// Arguments for the creation of a ChannelManager that are not deserialized.
4409 ///
4410 /// At a high-level, the process for deserializing a ChannelManager and resuming normal operation
4411 /// is:
4412 /// 1) Deserialize all stored ChannelMonitors.
4413 /// 2) Deserialize the ChannelManager by filling in this struct and calling:
4414 ///    <(BlockHash, ChannelManager)>::read(reader, args)
4415 ///    This may result in closing some Channels if the ChannelMonitor is newer than the stored
4416 ///    ChannelManager state to ensure no loss of funds. Thus, transactions may be broadcasted.
4417 /// 3) If you are not fetching full blocks, register all relevant ChannelMonitor outpoints the same
4418 ///    way you would handle a `chain::Filter` call using ChannelMonitor::get_outputs_to_watch() and
4419 ///    ChannelMonitor::get_funding_txo().
4420 /// 4) Reconnect blocks on your ChannelMonitors.
4421 /// 5) Disconnect/connect blocks on the ChannelManager.
4422 /// 6) Move the ChannelMonitors into your local chain::Watch.
4423 ///
4424 /// Note that the ordering of #4-6 is not of importance, however all three must occur before you
4425 /// call any other methods on the newly-deserialized ChannelManager.
4426 ///
4427 /// Note that because some channels may be closed during deserialization, it is critical that you
4428 /// always deserialize only the latest version of a ChannelManager and ChannelMonitors available to
4429 /// you. If you deserialize an old ChannelManager (during which force-closure transactions may be
4430 /// broadcast), and then later deserialize a newer version of the same ChannelManager (which will
4431 /// not force-close the same channels but consider them live), you may end up revoking a state for
4432 /// which you've already broadcasted the transaction.
4433 pub struct ChannelManagerReadArgs<'a, Signer: 'a + Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
4434         where M::Target: chain::Watch<Signer>,
4435         T::Target: BroadcasterInterface,
4436         K::Target: KeysInterface<Signer = Signer>,
4437         F::Target: FeeEstimator,
4438         L::Target: Logger,
4439 {
4440         /// The keys provider which will give us relevant keys. Some keys will be loaded during
4441         /// deserialization and KeysInterface::read_chan_signer will be used to read per-Channel
4442         /// signing data.
4443         pub keys_manager: K,
4444
4445         /// The fee_estimator for use in the ChannelManager in the future.
4446         ///
4447         /// No calls to the FeeEstimator will be made during deserialization.
4448         pub fee_estimator: F,
4449         /// The chain::Watch for use in the ChannelManager in the future.
4450         ///
4451         /// No calls to the chain::Watch will be made during deserialization. It is assumed that
4452         /// you have deserialized ChannelMonitors separately and will add them to your
4453         /// chain::Watch after deserializing this ChannelManager.
4454         pub chain_monitor: M,
4455
4456         /// The BroadcasterInterface which will be used in the ChannelManager in the future and may be
4457         /// used to broadcast the latest local commitment transactions of channels which must be
4458         /// force-closed during deserialization.
4459         pub tx_broadcaster: T,
4460         /// The Logger for use in the ChannelManager and which may be used to log information during
4461         /// deserialization.
4462         pub logger: L,
4463         /// Default settings used for new channels. Any existing channels will continue to use the
4464         /// runtime settings which were stored when the ChannelManager was serialized.
4465         pub default_config: UserConfig,
4466
4467         /// A map from channel funding outpoints to ChannelMonitors for those channels (ie
4468         /// value.get_funding_txo() should be the key).
4469         ///
4470         /// If a monitor is inconsistent with the channel state during deserialization the channel will
4471         /// be force-closed using the data in the ChannelMonitor and the channel will be dropped. This
4472         /// is true for missing channels as well. If there is a monitor missing for which we find
4473         /// channel data Err(DecodeError::InvalidValue) will be returned.
4474         ///
4475         /// In such cases the latest local transactions will be sent to the tx_broadcaster included in
4476         /// this struct.
4477         ///
4478         /// (C-not exported) because we have no HashMap bindings
4479         pub channel_monitors: HashMap<OutPoint, &'a mut ChannelMonitor<Signer>>,
4480 }
4481
4482 impl<'a, Signer: 'a + Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
4483                 ChannelManagerReadArgs<'a, Signer, M, T, K, F, L>
4484         where M::Target: chain::Watch<Signer>,
4485                 T::Target: BroadcasterInterface,
4486                 K::Target: KeysInterface<Signer = Signer>,
4487                 F::Target: FeeEstimator,
4488                 L::Target: Logger,
4489         {
4490         /// Simple utility function to create a ChannelManagerReadArgs which creates the monitor
4491         /// HashMap for you. This is primarily useful for C bindings where it is not practical to
4492         /// populate a HashMap directly from C.
4493         pub fn new(keys_manager: K, fee_estimator: F, chain_monitor: M, tx_broadcaster: T, logger: L, default_config: UserConfig,
4494                         mut channel_monitors: Vec<&'a mut ChannelMonitor<Signer>>) -> Self {
4495                 Self {
4496                         keys_manager, fee_estimator, chain_monitor, tx_broadcaster, logger, default_config,
4497                         channel_monitors: channel_monitors.drain(..).map(|monitor| { (monitor.get_funding_txo().0, monitor) }).collect()
4498                 }
4499         }
4500 }
4501
4502 // Implement ReadableArgs for an Arc'd ChannelManager to make it a bit easier to work with the
4503 // SipmleArcChannelManager type:
4504 impl<'a, Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
4505         ReadableArgs<ChannelManagerReadArgs<'a, Signer, M, T, K, F, L>> for (BlockHash, Arc<ChannelManager<Signer, M, T, K, F, L>>)
4506         where M::Target: chain::Watch<Signer>,
4507         T::Target: BroadcasterInterface,
4508         K::Target: KeysInterface<Signer = Signer>,
4509         F::Target: FeeEstimator,
4510         L::Target: Logger,
4511 {
4512         fn read<R: ::std::io::Read>(reader: &mut R, args: ChannelManagerReadArgs<'a, Signer, M, T, K, F, L>) -> Result<Self, DecodeError> {
4513                 let (blockhash, chan_manager) = <(BlockHash, ChannelManager<Signer, M, T, K, F, L>)>::read(reader, args)?;
4514                 Ok((blockhash, Arc::new(chan_manager)))
4515         }
4516 }
4517
4518 impl<'a, Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
4519         ReadableArgs<ChannelManagerReadArgs<'a, Signer, M, T, K, F, L>> for (BlockHash, ChannelManager<Signer, M, T, K, F, L>)
4520         where M::Target: chain::Watch<Signer>,
4521         T::Target: BroadcasterInterface,
4522         K::Target: KeysInterface<Signer = Signer>,
4523         F::Target: FeeEstimator,
4524         L::Target: Logger,
4525 {
4526         fn read<R: ::std::io::Read>(reader: &mut R, mut args: ChannelManagerReadArgs<'a, Signer, M, T, K, F, L>) -> Result<Self, DecodeError> {
4527                 let _ver: u8 = Readable::read(reader)?;
4528                 let min_ver: u8 = Readable::read(reader)?;
4529                 if min_ver > SERIALIZATION_VERSION {
4530                         return Err(DecodeError::UnknownVersion);
4531                 }
4532
4533                 let genesis_hash: BlockHash = Readable::read(reader)?;
4534                 let best_block_height: u32 = Readable::read(reader)?;
4535                 let best_block_hash: BlockHash = Readable::read(reader)?;
4536
4537                 let mut failed_htlcs = Vec::new();
4538
4539                 let channel_count: u64 = Readable::read(reader)?;
4540                 let mut funding_txo_set = HashSet::with_capacity(cmp::min(channel_count as usize, 128));
4541                 let mut by_id = HashMap::with_capacity(cmp::min(channel_count as usize, 128));
4542                 let mut short_to_id = HashMap::with_capacity(cmp::min(channel_count as usize, 128));
4543                 for _ in 0..channel_count {
4544                         let mut channel: Channel<Signer> = Channel::read(reader, &args.keys_manager)?;
4545                         let funding_txo = channel.get_funding_txo().ok_or(DecodeError::InvalidValue)?;
4546                         funding_txo_set.insert(funding_txo.clone());
4547                         if let Some(ref mut monitor) = args.channel_monitors.get_mut(&funding_txo) {
4548                                 if channel.get_cur_holder_commitment_transaction_number() < monitor.get_cur_holder_commitment_number() ||
4549                                                 channel.get_revoked_counterparty_commitment_transaction_number() < monitor.get_min_seen_secret() ||
4550                                                 channel.get_cur_counterparty_commitment_transaction_number() < monitor.get_cur_counterparty_commitment_number() ||
4551                                                 channel.get_latest_monitor_update_id() > monitor.get_latest_update_id() {
4552                                         // If the channel is ahead of the monitor, return InvalidValue:
4553                                         return Err(DecodeError::InvalidValue);
4554                                 } else if channel.get_cur_holder_commitment_transaction_number() > monitor.get_cur_holder_commitment_number() ||
4555                                                 channel.get_revoked_counterparty_commitment_transaction_number() > monitor.get_min_seen_secret() ||
4556                                                 channel.get_cur_counterparty_commitment_transaction_number() > monitor.get_cur_counterparty_commitment_number() ||
4557                                                 channel.get_latest_monitor_update_id() < monitor.get_latest_update_id() {
4558                                         // But if the channel is behind of the monitor, close the channel:
4559                                         let (_, mut new_failed_htlcs) = channel.force_shutdown(true);
4560                                         failed_htlcs.append(&mut new_failed_htlcs);
4561                                         monitor.broadcast_latest_holder_commitment_txn(&args.tx_broadcaster, &args.logger);
4562                                 } else {
4563                                         if let Some(short_channel_id) = channel.get_short_channel_id() {
4564                                                 short_to_id.insert(short_channel_id, channel.channel_id());
4565                                         }
4566                                         by_id.insert(channel.channel_id(), channel);
4567                                 }
4568                         } else {
4569                                 return Err(DecodeError::InvalidValue);
4570                         }
4571                 }
4572
4573                 for (ref funding_txo, ref mut monitor) in args.channel_monitors.iter_mut() {
4574                         if !funding_txo_set.contains(funding_txo) {
4575                                 monitor.broadcast_latest_holder_commitment_txn(&args.tx_broadcaster, &args.logger);
4576                         }
4577                 }
4578
4579                 const MAX_ALLOC_SIZE: usize = 1024 * 64;
4580                 let forward_htlcs_count: u64 = Readable::read(reader)?;
4581                 let mut forward_htlcs = HashMap::with_capacity(cmp::min(forward_htlcs_count as usize, 128));
4582                 for _ in 0..forward_htlcs_count {
4583                         let short_channel_id = Readable::read(reader)?;
4584                         let pending_forwards_count: u64 = Readable::read(reader)?;
4585                         let mut pending_forwards = Vec::with_capacity(cmp::min(pending_forwards_count as usize, MAX_ALLOC_SIZE/mem::size_of::<HTLCForwardInfo>()));
4586                         for _ in 0..pending_forwards_count {
4587                                 pending_forwards.push(Readable::read(reader)?);
4588                         }
4589                         forward_htlcs.insert(short_channel_id, pending_forwards);
4590                 }
4591
4592                 let claimable_htlcs_count: u64 = Readable::read(reader)?;
4593                 let mut claimable_htlcs = HashMap::with_capacity(cmp::min(claimable_htlcs_count as usize, 128));
4594                 for _ in 0..claimable_htlcs_count {
4595                         let payment_hash = Readable::read(reader)?;
4596                         let previous_hops_len: u64 = Readable::read(reader)?;
4597                         let mut previous_hops = Vec::with_capacity(cmp::min(previous_hops_len as usize, MAX_ALLOC_SIZE/mem::size_of::<ClaimableHTLC>()));
4598                         for _ in 0..previous_hops_len {
4599                                 previous_hops.push(Readable::read(reader)?);
4600                         }
4601                         claimable_htlcs.insert(payment_hash, previous_hops);
4602                 }
4603
4604                 let peer_count: u64 = Readable::read(reader)?;
4605                 let mut per_peer_state = HashMap::with_capacity(cmp::min(peer_count as usize, MAX_ALLOC_SIZE/mem::size_of::<(PublicKey, Mutex<PeerState>)>()));
4606                 for _ in 0..peer_count {
4607                         let peer_pubkey = Readable::read(reader)?;
4608                         let peer_state = PeerState {
4609                                 latest_features: Readable::read(reader)?,
4610                         };
4611                         per_peer_state.insert(peer_pubkey, Mutex::new(peer_state));
4612                 }
4613
4614                 let event_count: u64 = Readable::read(reader)?;
4615                 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>()));
4616                 for _ in 0..event_count {
4617                         match MaybeReadable::read(reader)? {
4618                                 Some(event) => pending_events_read.push(event),
4619                                 None => continue,
4620                         }
4621                 }
4622
4623                 let background_event_count: u64 = Readable::read(reader)?;
4624                 let mut pending_background_events_read: Vec<BackgroundEvent> = Vec::with_capacity(cmp::min(background_event_count as usize, MAX_ALLOC_SIZE/mem::size_of::<BackgroundEvent>()));
4625                 for _ in 0..background_event_count {
4626                         match <u8 as Readable>::read(reader)? {
4627                                 0 => pending_background_events_read.push(BackgroundEvent::ClosingMonitorUpdate((Readable::read(reader)?, Readable::read(reader)?))),
4628                                 _ => return Err(DecodeError::InvalidValue),
4629                         }
4630                 }
4631
4632                 let last_node_announcement_serial: u32 = Readable::read(reader)?;
4633                 let highest_seen_timestamp: u32 = Readable::read(reader)?;
4634
4635                 let pending_inbound_payment_count: u64 = Readable::read(reader)?;
4636                 let mut pending_inbound_payments: HashMap<PaymentHash, PendingInboundPayment> = HashMap::with_capacity(cmp::min(pending_inbound_payment_count as usize, MAX_ALLOC_SIZE/(3*32)));
4637                 for _ in 0..pending_inbound_payment_count {
4638                         if pending_inbound_payments.insert(Readable::read(reader)?, Readable::read(reader)?).is_some() {
4639                                 return Err(DecodeError::InvalidValue);
4640                         }
4641                 }
4642
4643                 let mut secp_ctx = Secp256k1::new();
4644                 secp_ctx.seeded_randomize(&args.keys_manager.get_secure_random_bytes());
4645
4646                 let channel_manager = ChannelManager {
4647                         genesis_hash,
4648                         fee_estimator: args.fee_estimator,
4649                         chain_monitor: args.chain_monitor,
4650                         tx_broadcaster: args.tx_broadcaster,
4651
4652                         best_block: RwLock::new(BestBlock::new(best_block_hash, best_block_height)),
4653
4654                         channel_state: Mutex::new(ChannelHolder {
4655                                 by_id,
4656                                 short_to_id,
4657                                 forward_htlcs,
4658                                 claimable_htlcs,
4659                                 pending_msg_events: Vec::new(),
4660                         }),
4661                         pending_inbound_payments: Mutex::new(pending_inbound_payments),
4662
4663                         our_network_key: args.keys_manager.get_node_secret(),
4664                         our_network_pubkey: PublicKey::from_secret_key(&secp_ctx, &args.keys_manager.get_node_secret()),
4665                         secp_ctx,
4666
4667                         last_node_announcement_serial: AtomicUsize::new(last_node_announcement_serial as usize),
4668                         highest_seen_timestamp: AtomicUsize::new(highest_seen_timestamp as usize),
4669
4670                         per_peer_state: RwLock::new(per_peer_state),
4671
4672                         pending_events: Mutex::new(pending_events_read),
4673                         pending_background_events: Mutex::new(pending_background_events_read),
4674                         total_consistency_lock: RwLock::new(()),
4675                         persistence_notifier: PersistenceNotifier::new(),
4676
4677                         keys_manager: args.keys_manager,
4678                         logger: args.logger,
4679                         default_configuration: args.default_config,
4680                 };
4681
4682                 for htlc_source in failed_htlcs.drain(..) {
4683                         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() });
4684                 }
4685
4686                 //TODO: Broadcast channel update for closed channels, but only after we've made a
4687                 //connection or two.
4688
4689                 Ok((best_block_hash.clone(), channel_manager))
4690         }
4691 }
4692
4693 #[cfg(test)]
4694 mod tests {
4695         use ln::channelmanager::PersistenceNotifier;
4696         use std::sync::Arc;
4697         use std::sync::atomic::{AtomicBool, Ordering};
4698         use std::thread;
4699         use std::time::Duration;
4700
4701         #[test]
4702         fn test_wait_timeout() {
4703                 let persistence_notifier = Arc::new(PersistenceNotifier::new());
4704                 let thread_notifier = Arc::clone(&persistence_notifier);
4705
4706                 let exit_thread = Arc::new(AtomicBool::new(false));
4707                 let exit_thread_clone = exit_thread.clone();
4708                 thread::spawn(move || {
4709                         loop {
4710                                 let &(ref persist_mtx, ref cnd) = &thread_notifier.persistence_lock;
4711                                 let mut persistence_lock = persist_mtx.lock().unwrap();
4712                                 *persistence_lock = true;
4713                                 cnd.notify_all();
4714
4715                                 if exit_thread_clone.load(Ordering::SeqCst) {
4716                                         break
4717                                 }
4718                         }
4719                 });
4720
4721                 // Check that we can block indefinitely until updates are available.
4722                 let _ = persistence_notifier.wait();
4723
4724                 // Check that the PersistenceNotifier will return after the given duration if updates are
4725                 // available.
4726                 loop {
4727                         if persistence_notifier.wait_timeout(Duration::from_millis(100)) {
4728                                 break
4729                         }
4730                 }
4731
4732                 exit_thread.store(true, Ordering::SeqCst);
4733
4734                 // Check that the PersistenceNotifier will return after the given duration even if no updates
4735                 // are available.
4736                 loop {
4737                         if !persistence_notifier.wait_timeout(Duration::from_millis(100)) {
4738                                 break
4739                         }
4740                 }
4741         }
4742 }
4743
4744 #[cfg(all(any(test, feature = "_test_utils"), feature = "unstable"))]
4745 pub mod bench {
4746         use chain::Listen;
4747         use chain::chainmonitor::ChainMonitor;
4748         use chain::channelmonitor::Persist;
4749         use chain::keysinterface::{KeysManager, InMemorySigner};
4750         use ln::channelmanager::{BestBlock, ChainParameters, ChannelManager, PaymentHash, PaymentPreimage};
4751         use ln::features::{InitFeatures, InvoiceFeatures};
4752         use ln::functional_test_utils::*;
4753         use ln::msgs::ChannelMessageHandler;
4754         use routing::network_graph::NetworkGraph;
4755         use routing::router::get_route;
4756         use util::test_utils;
4757         use util::config::UserConfig;
4758         use util::events::{Event, EventsProvider, MessageSendEvent, MessageSendEventsProvider};
4759
4760         use bitcoin::hashes::Hash;
4761         use bitcoin::hashes::sha256::Hash as Sha256;
4762         use bitcoin::{Block, BlockHeader, Transaction, TxOut};
4763
4764         use std::sync::Mutex;
4765
4766         use test::Bencher;
4767
4768         struct NodeHolder<'a, P: Persist<InMemorySigner>> {
4769                 node: &'a ChannelManager<InMemorySigner,
4770                         &'a ChainMonitor<InMemorySigner, &'a test_utils::TestChainSource,
4771                                 &'a test_utils::TestBroadcaster, &'a test_utils::TestFeeEstimator,
4772                                 &'a test_utils::TestLogger, &'a P>,
4773                         &'a test_utils::TestBroadcaster, &'a KeysManager,
4774                         &'a test_utils::TestFeeEstimator, &'a test_utils::TestLogger>
4775         }
4776
4777         #[cfg(test)]
4778         #[bench]
4779         fn bench_sends(bench: &mut Bencher) {
4780                 bench_two_sends(bench, test_utils::TestPersister::new(), test_utils::TestPersister::new());
4781         }
4782
4783         pub fn bench_two_sends<P: Persist<InMemorySigner>>(bench: &mut Bencher, persister_a: P, persister_b: P) {
4784                 // Do a simple benchmark of sending a payment back and forth between two nodes.
4785                 // Note that this is unrealistic as each payment send will require at least two fsync
4786                 // calls per node.
4787                 let network = bitcoin::Network::Testnet;
4788                 let genesis_hash = bitcoin::blockdata::constants::genesis_block(network).header.block_hash();
4789
4790                 let tx_broadcaster = test_utils::TestBroadcaster{txn_broadcasted: Mutex::new(Vec::new())};
4791                 let fee_estimator = test_utils::TestFeeEstimator { sat_per_kw: 253 };
4792
4793                 let mut config: UserConfig = Default::default();
4794                 config.own_channel_config.minimum_depth = 1;
4795
4796                 let logger_a = test_utils::TestLogger::with_id("node a".to_owned());
4797                 let chain_monitor_a = ChainMonitor::new(None, &tx_broadcaster, &logger_a, &fee_estimator, &persister_a);
4798                 let seed_a = [1u8; 32];
4799                 let keys_manager_a = KeysManager::new(&seed_a, 42, 42);
4800                 let node_a = ChannelManager::new(&fee_estimator, &chain_monitor_a, &tx_broadcaster, &logger_a, &keys_manager_a, config.clone(), ChainParameters {
4801                         network,
4802                         best_block: BestBlock::from_genesis(network),
4803                 });
4804                 let node_a_holder = NodeHolder { node: &node_a };
4805
4806                 let logger_b = test_utils::TestLogger::with_id("node a".to_owned());
4807                 let chain_monitor_b = ChainMonitor::new(None, &tx_broadcaster, &logger_a, &fee_estimator, &persister_b);
4808                 let seed_b = [2u8; 32];
4809                 let keys_manager_b = KeysManager::new(&seed_b, 42, 42);
4810                 let node_b = ChannelManager::new(&fee_estimator, &chain_monitor_b, &tx_broadcaster, &logger_b, &keys_manager_b, config.clone(), ChainParameters {
4811                         network,
4812                         best_block: BestBlock::from_genesis(network),
4813                 });
4814                 let node_b_holder = NodeHolder { node: &node_b };
4815
4816                 node_a.create_channel(node_b.get_our_node_id(), 8_000_000, 100_000_000, 42, None).unwrap();
4817                 node_b.handle_open_channel(&node_a.get_our_node_id(), InitFeatures::known(), &get_event_msg!(node_a_holder, MessageSendEvent::SendOpenChannel, node_b.get_our_node_id()));
4818                 node_a.handle_accept_channel(&node_b.get_our_node_id(), InitFeatures::known(), &get_event_msg!(node_b_holder, MessageSendEvent::SendAcceptChannel, node_a.get_our_node_id()));
4819
4820                 let tx;
4821                 if let Event::FundingGenerationReady { temporary_channel_id, output_script, .. } = get_event!(node_a_holder, Event::FundingGenerationReady) {
4822                         tx = Transaction { version: 2, lock_time: 0, input: Vec::new(), output: vec![TxOut {
4823                                 value: 8_000_000, script_pubkey: output_script,
4824                         }]};
4825                         node_a.funding_transaction_generated(&temporary_channel_id, tx.clone()).unwrap();
4826                 } else { panic!(); }
4827
4828                 node_b.handle_funding_created(&node_a.get_our_node_id(), &get_event_msg!(node_a_holder, MessageSendEvent::SendFundingCreated, node_b.get_our_node_id()));
4829                 node_a.handle_funding_signed(&node_b.get_our_node_id(), &get_event_msg!(node_b_holder, MessageSendEvent::SendFundingSigned, node_a.get_our_node_id()));
4830
4831                 assert_eq!(&tx_broadcaster.txn_broadcasted.lock().unwrap()[..], &[tx.clone()]);
4832
4833                 let block = Block {
4834                         header: BlockHeader { version: 0x20000000, prev_blockhash: genesis_hash, merkle_root: Default::default(), time: 42, bits: 42, nonce: 42 },
4835                         txdata: vec![tx],
4836                 };
4837                 Listen::block_connected(&node_a, &block, 1);
4838                 Listen::block_connected(&node_b, &block, 1);
4839
4840                 node_a.handle_funding_locked(&node_b.get_our_node_id(), &get_event_msg!(node_b_holder, MessageSendEvent::SendFundingLocked, node_a.get_our_node_id()));
4841                 node_b.handle_funding_locked(&node_a.get_our_node_id(), &get_event_msg!(node_a_holder, MessageSendEvent::SendFundingLocked, node_b.get_our_node_id()));
4842
4843                 let dummy_graph = NetworkGraph::new(genesis_hash);
4844
4845                 let mut payment_count: u64 = 0;
4846                 macro_rules! send_payment {
4847                         ($node_a: expr, $node_b: expr) => {
4848                                 let usable_channels = $node_a.list_usable_channels();
4849                                 let route = get_route(&$node_a.get_our_node_id(), &dummy_graph, &$node_b.get_our_node_id(), Some(InvoiceFeatures::known()),
4850                                         Some(&usable_channels.iter().map(|r| r).collect::<Vec<_>>()), &[], 10_000, TEST_FINAL_CLTV, &logger_a).unwrap();
4851
4852                                 let mut payment_preimage = PaymentPreimage([0; 32]);
4853                                 payment_preimage.0[0..8].copy_from_slice(&payment_count.to_le_bytes());
4854                                 payment_count += 1;
4855                                 let payment_hash = PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner());
4856                                 let payment_secret = $node_b.create_inbound_payment_for_hash(payment_hash, None, 7200, 0).unwrap();
4857
4858                                 $node_a.send_payment(&route, payment_hash, &Some(payment_secret)).unwrap();
4859                                 let payment_event = SendEvent::from_event($node_a.get_and_clear_pending_msg_events().pop().unwrap());
4860                                 $node_b.handle_update_add_htlc(&$node_a.get_our_node_id(), &payment_event.msgs[0]);
4861                                 $node_b.handle_commitment_signed(&$node_a.get_our_node_id(), &payment_event.commitment_msg);
4862                                 let (raa, cs) = get_revoke_commit_msgs!(NodeHolder { node: &$node_b }, $node_a.get_our_node_id());
4863                                 $node_a.handle_revoke_and_ack(&$node_b.get_our_node_id(), &raa);
4864                                 $node_a.handle_commitment_signed(&$node_b.get_our_node_id(), &cs);
4865                                 $node_b.handle_revoke_and_ack(&$node_a.get_our_node_id(), &get_event_msg!(NodeHolder { node: &$node_a }, MessageSendEvent::SendRevokeAndACK, $node_b.get_our_node_id()));
4866
4867                                 expect_pending_htlcs_forwardable!(NodeHolder { node: &$node_b });
4868                                 expect_payment_received!(NodeHolder { node: &$node_b }, payment_hash, payment_secret, 10_000);
4869                                 assert!($node_b.claim_funds(payment_preimage));
4870
4871                                 match $node_b.get_and_clear_pending_msg_events().pop().unwrap() {
4872                                         MessageSendEvent::UpdateHTLCs { node_id, updates } => {
4873                                                 assert_eq!(node_id, $node_a.get_our_node_id());
4874                                                 $node_a.handle_update_fulfill_htlc(&$node_b.get_our_node_id(), &updates.update_fulfill_htlcs[0]);
4875                                                 $node_a.handle_commitment_signed(&$node_b.get_our_node_id(), &updates.commitment_signed);
4876                                         },
4877                                         _ => panic!("Failed to generate claim event"),
4878                                 }
4879
4880                                 let (raa, cs) = get_revoke_commit_msgs!(NodeHolder { node: &$node_a }, $node_b.get_our_node_id());
4881                                 $node_b.handle_revoke_and_ack(&$node_a.get_our_node_id(), &raa);
4882                                 $node_b.handle_commitment_signed(&$node_a.get_our_node_id(), &cs);
4883                                 $node_a.handle_revoke_and_ack(&$node_b.get_our_node_id(), &get_event_msg!(NodeHolder { node: &$node_b }, MessageSendEvent::SendRevokeAndACK, $node_a.get_our_node_id()));
4884
4885                                 expect_payment_sent!(NodeHolder { node: &$node_a }, payment_preimage);
4886                         }
4887                 }
4888
4889                 bench.iter(|| {
4890                         send_payment!(node_a, node_b);
4891                         send_payment!(node_b, node_a);
4892                 });
4893         }
4894 }