Support (de)serializing payment_data in onion TLVs and track them
[rust-lightning] / lightning / src / ln / channelmanager.rs
1 //! The top-level channel management and payment tracking stuff lives here.
2 //!
3 //! The ChannelManager is the main chunk of logic implementing the lightning protocol and is
4 //! responsible for tracking which channels are open, HTLCs are in flight and reestablishing those
5 //! upon reconnect to the relevant peer(s).
6 //!
7 //! It does not manage routing logic (see ln::router for that) nor does it manage constructing
8 //! on-chain transactions (it only monitors the chain to watch for any force-closes that might
9 //! imply it needs to fail HTLCs/payments/channels it manages).
10
11 use bitcoin::blockdata::block::BlockHeader;
12 use bitcoin::blockdata::transaction::Transaction;
13 use bitcoin::blockdata::constants::genesis_block;
14 use bitcoin::network::constants::Network;
15 use bitcoin::util::hash::BitcoinHash;
16
17 use bitcoin_hashes::{Hash, HashEngine};
18 use bitcoin_hashes::hmac::{Hmac, HmacEngine};
19 use bitcoin_hashes::sha256::Hash as Sha256;
20 use bitcoin_hashes::sha256d::Hash as Sha256dHash;
21 use bitcoin_hashes::cmp::fixed_time_eq;
22
23 use secp256k1::key::{SecretKey,PublicKey};
24 use secp256k1::Secp256k1;
25 use secp256k1::ecdh::SharedSecret;
26 use secp256k1;
27
28 use chain::chaininterface::{BroadcasterInterface,ChainListener,FeeEstimator};
29 use chain::transaction::OutPoint;
30 use ln::channel::{Channel, ChannelError};
31 use ln::channelmonitor::{ChannelMonitor, ChannelMonitorUpdate, ChannelMonitorUpdateErr, ManyChannelMonitor, CLTV_CLAIM_BUFFER, LATENCY_GRACE_PERIOD_BLOCKS, ANTI_REORG_DELAY};
32 use ln::features::{InitFeatures, NodeFeatures};
33 use ln::router::Route;
34 use ln::msgs;
35 use ln::onion_utils;
36 use ln::msgs::{ChannelMessageHandler, DecodeError, LightningError};
37 use chain::keysinterface::{ChannelKeys, KeysInterface, KeysManager, InMemoryChannelKeys};
38 use util::config::UserConfig;
39 use util::{byte_utils, events};
40 use util::ser::{Readable, ReadableArgs, Writeable, Writer};
41 use util::chacha20::{ChaCha20, ChaChaReader};
42 use util::logger::Logger;
43 use util::errors::APIError;
44
45 use std::{cmp, mem};
46 use std::collections::{HashMap, hash_map, HashSet};
47 use std::io::{Cursor, Read};
48 use std::sync::{Arc, Mutex, MutexGuard, RwLock};
49 use std::sync::atomic::{AtomicUsize, Ordering};
50 use std::time::Duration;
51 use std::marker::{Sync, Send};
52 use std::ops::Deref;
53
54 // We hold various information about HTLC relay in the HTLC objects in Channel itself:
55 //
56 // Upon receipt of an HTLC from a peer, we'll give it a PendingHTLCStatus indicating if it should
57 // forward the HTLC with information it will give back to us when it does so, or if it should Fail
58 // the HTLC with the relevant message for the Channel to handle giving to the remote peer.
59 //
60 // Once said HTLC is committed in the Channel, if the PendingHTLCStatus indicated Forward, the
61 // Channel will return the PendingHTLCInfo back to us, and we will create an HTLCForwardInfo
62 // with it to track where it came from (in case of onwards-forward error), waiting a random delay
63 // before we forward it.
64 //
65 // We will then use HTLCForwardInfo's PendingHTLCInfo to construct an outbound HTLC, with a
66 // relevant HTLCSource::PreviousHopData filled in to indicate where it came from (which we can use
67 // to either fail-backwards or fulfill the HTLC backwards along the relevant path).
68 // Alternatively, we can fill an outbound HTLC with a HTLCSource::OutboundRoute indicating this is
69 // our payment, which we can use to decode errors or inform the user that the payment was sent.
70
71 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
72 enum PendingHTLCRouting {
73         Forward {
74                 onion_packet: msgs::OnionPacket,
75                 short_channel_id: u64, // This should be NonZero<u64> eventually when we bump MSRV
76         },
77         Receive {
78                 payment_data: Option<msgs::FinalOnionHopData>,
79         },
80 }
81
82 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
83 pub(super) struct PendingHTLCInfo {
84         routing: PendingHTLCRouting,
85         incoming_shared_secret: [u8; 32],
86         payment_hash: PaymentHash,
87         pub(super) amt_to_forward: u64,
88         pub(super) outgoing_cltv_value: u32,
89 }
90
91 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
92 pub(super) enum HTLCFailureMsg {
93         Relay(msgs::UpdateFailHTLC),
94         Malformed(msgs::UpdateFailMalformedHTLC),
95 }
96
97 /// Stores whether we can't forward an HTLC or relevant forwarding info
98 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
99 pub(super) enum PendingHTLCStatus {
100         Forward(PendingHTLCInfo),
101         Fail(HTLCFailureMsg),
102 }
103
104 pub(super) enum HTLCForwardInfo {
105         AddHTLC {
106                 prev_short_channel_id: u64,
107                 prev_htlc_id: u64,
108                 forward_info: PendingHTLCInfo,
109         },
110         FailHTLC {
111                 htlc_id: u64,
112                 err_packet: msgs::OnionErrorPacket,
113         },
114 }
115
116 /// Tracks the inbound corresponding to an outbound HTLC
117 #[derive(Clone, PartialEq)]
118 pub(super) struct HTLCPreviousHopData {
119         short_channel_id: u64,
120         htlc_id: u64,
121         incoming_packet_shared_secret: [u8; 32],
122 }
123
124 struct ClaimableHTLC {
125         prev_hop: HTLCPreviousHopData,
126         value: u64,
127         /// Filled in when the HTLC was received with a payment_secret packet, which contains a
128         /// total_msat (which may differ from value if this is a Multi-Path Payment) and a
129         /// payment_secret which prevents path-probing attacks and can associate different HTLCs which
130         /// are part of the same payment.
131         payment_data: Option<msgs::FinalOnionHopData>,
132 }
133
134 /// Tracks the inbound corresponding to an outbound HTLC
135 #[derive(Clone, PartialEq)]
136 pub(super) enum HTLCSource {
137         PreviousHopData(HTLCPreviousHopData),
138         OutboundRoute {
139                 route: Route,
140                 session_priv: SecretKey,
141                 /// Technically we can recalculate this from the route, but we cache it here to avoid
142                 /// doing a double-pass on route when we get a failure back
143                 first_hop_htlc_msat: u64,
144         },
145 }
146 #[cfg(test)]
147 impl HTLCSource {
148         pub fn dummy() -> Self {
149                 HTLCSource::OutboundRoute {
150                         route: Route { hops: Vec::new() },
151                         session_priv: SecretKey::from_slice(&[1; 32]).unwrap(),
152                         first_hop_htlc_msat: 0,
153                 }
154         }
155 }
156
157 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
158 pub(super) enum HTLCFailReason {
159         LightningError {
160                 err: msgs::OnionErrorPacket,
161         },
162         Reason {
163                 failure_code: u16,
164                 data: Vec<u8>,
165         }
166 }
167
168 /// payment_hash type, use to cross-lock hop
169 #[derive(Hash, Copy, Clone, PartialEq, Eq, Debug)]
170 pub struct PaymentHash(pub [u8;32]);
171 /// payment_preimage type, use to route payment between hop
172 #[derive(Hash, Copy, Clone, PartialEq, Eq, Debug)]
173 pub struct PaymentPreimage(pub [u8;32]);
174
175 type ShutdownResult = (Option<OutPoint>, ChannelMonitorUpdate, Vec<(HTLCSource, PaymentHash)>);
176
177 /// Error type returned across the channel_state mutex boundary. When an Err is generated for a
178 /// Channel, we generally end up with a ChannelError::Close for which we have to close the channel
179 /// immediately (ie with no further calls on it made). Thus, this step happens inside a
180 /// channel_state lock. We then return the set of things that need to be done outside the lock in
181 /// this struct and call handle_error!() on it.
182
183 struct MsgHandleErrInternal {
184         err: msgs::LightningError,
185         shutdown_finish: Option<(ShutdownResult, Option<msgs::ChannelUpdate>)>,
186 }
187 impl MsgHandleErrInternal {
188         #[inline]
189         fn send_err_msg_no_close(err: &'static str, channel_id: [u8; 32]) -> Self {
190                 Self {
191                         err: LightningError {
192                                 err,
193                                 action: msgs::ErrorAction::SendErrorMessage {
194                                         msg: msgs::ErrorMessage {
195                                                 channel_id,
196                                                 data: err.to_string()
197                                         },
198                                 },
199                         },
200                         shutdown_finish: None,
201                 }
202         }
203         #[inline]
204         fn ignore_no_close(err: &'static str) -> Self {
205                 Self {
206                         err: LightningError {
207                                 err,
208                                 action: msgs::ErrorAction::IgnoreError,
209                         },
210                         shutdown_finish: None,
211                 }
212         }
213         #[inline]
214         fn from_no_close(err: msgs::LightningError) -> Self {
215                 Self { err, shutdown_finish: None }
216         }
217         #[inline]
218         fn from_finish_shutdown(err: &'static str, channel_id: [u8; 32], shutdown_res: ShutdownResult, channel_update: Option<msgs::ChannelUpdate>) -> Self {
219                 Self {
220                         err: LightningError {
221                                 err,
222                                 action: msgs::ErrorAction::SendErrorMessage {
223                                         msg: msgs::ErrorMessage {
224                                                 channel_id,
225                                                 data: err.to_string()
226                                         },
227                                 },
228                         },
229                         shutdown_finish: Some((shutdown_res, channel_update)),
230                 }
231         }
232         #[inline]
233         fn from_chan_no_close(err: ChannelError, channel_id: [u8; 32]) -> Self {
234                 Self {
235                         err: match err {
236                                 ChannelError::Ignore(msg) => LightningError {
237                                         err: msg,
238                                         action: msgs::ErrorAction::IgnoreError,
239                                 },
240                                 ChannelError::Close(msg) => LightningError {
241                                         err: msg,
242                                         action: msgs::ErrorAction::SendErrorMessage {
243                                                 msg: msgs::ErrorMessage {
244                                                         channel_id,
245                                                         data: msg.to_string()
246                                                 },
247                                         },
248                                 },
249                                 ChannelError::CloseDelayBroadcast { msg, .. } => LightningError {
250                                         err: msg,
251                                         action: msgs::ErrorAction::SendErrorMessage {
252                                                 msg: msgs::ErrorMessage {
253                                                         channel_id,
254                                                         data: msg.to_string()
255                                                 },
256                                         },
257                                 },
258                         },
259                         shutdown_finish: None,
260                 }
261         }
262 }
263
264 /// We hold back HTLCs we intend to relay for a random interval greater than this (see
265 /// Event::PendingHTLCsForwardable for the API guidelines indicating how long should be waited).
266 /// This provides some limited amount of privacy. Ideally this would range from somewhere like one
267 /// second to 30 seconds, but people expect lightning to be, you know, kinda fast, sadly.
268 const MIN_HTLC_RELAY_HOLDING_CELL_MILLIS: u64 = 100;
269
270 /// For events which result in both a RevokeAndACK and a CommitmentUpdate, by default they should
271 /// be sent in the order they appear in the return value, however sometimes the order needs to be
272 /// variable at runtime (eg Channel::channel_reestablish needs to re-send messages in the order
273 /// they were originally sent). In those cases, this enum is also returned.
274 #[derive(Clone, PartialEq)]
275 pub(super) enum RAACommitmentOrder {
276         /// Send the CommitmentUpdate messages first
277         CommitmentFirst,
278         /// Send the RevokeAndACK message first
279         RevokeAndACKFirst,
280 }
281
282 // Note this is only exposed in cfg(test):
283 pub(super) struct ChannelHolder<ChanSigner: ChannelKeys> {
284         pub(super) by_id: HashMap<[u8; 32], Channel<ChanSigner>>,
285         pub(super) short_to_id: HashMap<u64, [u8; 32]>,
286         /// short channel id -> forward infos. Key of 0 means payments received
287         /// Note that while this is held in the same mutex as the channels themselves, no consistency
288         /// guarantees are made about the existence of a channel with the short id here, nor the short
289         /// ids in the PendingHTLCInfo!
290         pub(super) forward_htlcs: HashMap<u64, Vec<HTLCForwardInfo>>,
291         /// Tracks HTLCs that were to us and can be failed/claimed by the user
292         /// Note that while this is held in the same mutex as the channels themselves, no consistency
293         /// guarantees are made about the channels given here actually existing anymore by the time you
294         /// go to read them!
295         claimable_htlcs: HashMap<PaymentHash, Vec<ClaimableHTLC>>,
296         /// Messages to send to peers - pushed to in the same lock that they are generated in (except
297         /// for broadcast messages, where ordering isn't as strict).
298         pub(super) pending_msg_events: Vec<events::MessageSendEvent>,
299 }
300
301 /// State we hold per-peer. In the future we should put channels in here, but for now we only hold
302 /// the latest Init features we heard from the peer.
303 struct PeerState {
304         latest_features: InitFeatures,
305 }
306
307 #[cfg(not(any(target_pointer_width = "32", target_pointer_width = "64")))]
308 const ERR: () = "You need at least 32 bit pointers (well, usize, but we'll assume they're the same) for ChannelManager::latest_block_height";
309
310 /// SimpleArcChannelManager is useful when you need a ChannelManager with a static lifetime, e.g.
311 /// when you're using lightning-net-tokio (since tokio::spawn requires parameters with static
312 /// lifetimes). Other times you can afford a reference, which is more efficient, in which case
313 /// SimpleRefChannelManager is the more appropriate type. Defining these type aliases prevents
314 /// issues such as overly long function definitions. Note that the ChannelManager can take any
315 /// type that implements KeysInterface for its keys manager, but this type alias chooses the
316 /// concrete type of the KeysManager.
317 pub type SimpleArcChannelManager<M, T, F> = Arc<ChannelManager<InMemoryChannelKeys, Arc<M>, Arc<T>, Arc<KeysManager>, Arc<F>>>;
318
319 /// SimpleRefChannelManager is a type alias for a ChannelManager reference, and is the reference
320 /// counterpart to the SimpleArcChannelManager type alias. Use this type by default when you don't
321 /// need a ChannelManager with a static lifetime. You'll need a static lifetime in cases such as
322 /// usage of lightning-net-tokio (since tokio::spawn requires parameters with static lifetimes).
323 /// But if this is not necessary, using a reference is more efficient. Defining these type aliases
324 /// helps with issues such as long function definitions. Note that the ChannelManager can take any
325 /// type that implements KeysInterface for its keys manager, but this type alias chooses the
326 /// concrete type of the KeysManager.
327 pub type SimpleRefChannelManager<'a, 'b, 'c, 'd, M, T, F> = ChannelManager<InMemoryChannelKeys, &'a M, &'b T, &'c KeysManager, &'d F>;
328
329 /// Manager which keeps track of a number of channels and sends messages to the appropriate
330 /// channel, also tracking HTLC preimages and forwarding onion packets appropriately.
331 ///
332 /// Implements ChannelMessageHandler, handling the multi-channel parts and passing things through
333 /// to individual Channels.
334 ///
335 /// Implements Writeable to write out all channel state to disk. Implies peer_disconnected() for
336 /// all peers during write/read (though does not modify this instance, only the instance being
337 /// serialized). This will result in any channels which have not yet exchanged funding_created (ie
338 /// called funding_transaction_generated for outbound channels).
339 ///
340 /// Note that you can be a bit lazier about writing out ChannelManager than you can be with
341 /// ChannelMonitors. With ChannelMonitors you MUST write each monitor update out to disk before
342 /// returning from ManyChannelMonitor::add_/update_monitor, with ChannelManagers, writing updates
343 /// happens out-of-band (and will prevent any other ChannelManager operations from occurring during
344 /// the serialization process). If the deserialized version is out-of-date compared to the
345 /// ChannelMonitors passed by reference to read(), those channels will be force-closed based on the
346 /// ChannelMonitor state and no funds will be lost (mod on-chain transaction fees).
347 ///
348 /// Note that the deserializer is only implemented for (Sha256dHash, ChannelManager), which
349 /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
350 /// the "reorg path" (ie call block_disconnected() until you get to a common block and then call
351 /// block_connected() to step towards your best block) upon deserialization before using the
352 /// object!
353 ///
354 /// Note that ChannelManager is responsible for tracking liveness of its channels and generating
355 /// ChannelUpdate messages informing peers that the channel is temporarily disabled. To avoid
356 /// spam due to quick disconnection/reconnection, updates are not sent until the channel has been
357 /// offline for a full minute. In order to track this, you must call
358 /// timer_chan_freshness_every_min roughly once per minute, though it doesn't have to be perfect.
359 ///
360 /// Rather than using a plain ChannelManager, it is preferable to use either a SimpleArcChannelManager
361 /// a SimpleRefChannelManager, for conciseness. See their documentation for more details, but
362 /// essentially you should default to using a SimpleRefChannelManager, and use a
363 /// SimpleArcChannelManager when you require a ChannelManager with a static lifetime, such as when
364 /// you're using lightning-net-tokio.
365 pub struct ChannelManager<ChanSigner: ChannelKeys, M: Deref, T: Deref, K: Deref, F: Deref>
366         where M::Target: ManyChannelMonitor<ChanSigner>,
367         T::Target: BroadcasterInterface,
368         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
369         F::Target: FeeEstimator,
370 {
371         default_configuration: UserConfig,
372         genesis_hash: Sha256dHash,
373         fee_estimator: F,
374         monitor: M,
375         tx_broadcaster: T,
376
377         #[cfg(test)]
378         pub(super) latest_block_height: AtomicUsize,
379         #[cfg(not(test))]
380         latest_block_height: AtomicUsize,
381         last_block_hash: Mutex<Sha256dHash>,
382         secp_ctx: Secp256k1<secp256k1::All>,
383
384         #[cfg(test)]
385         pub(super) channel_state: Mutex<ChannelHolder<ChanSigner>>,
386         #[cfg(not(test))]
387         channel_state: Mutex<ChannelHolder<ChanSigner>>,
388         our_network_key: SecretKey,
389
390         /// Used to track the last value sent in a node_announcement "timestamp" field. We ensure this
391         /// value increases strictly since we don't assume access to a time source.
392         last_node_announcement_serial: AtomicUsize,
393
394         /// The bulk of our storage will eventually be here (channels and message queues and the like).
395         /// If we are connected to a peer we always at least have an entry here, even if no channels
396         /// are currently open with that peer.
397         /// Because adding or removing an entry is rare, we usually take an outer read lock and then
398         /// operate on the inner value freely. Sadly, this prevents parallel operation when opening a
399         /// new channel.
400         per_peer_state: RwLock<HashMap<PublicKey, Mutex<PeerState>>>,
401
402         pending_events: Mutex<Vec<events::Event>>,
403         /// Used when we have to take a BIG lock to make sure everything is self-consistent.
404         /// Essentially just when we're serializing ourselves out.
405         /// Taken first everywhere where we are making changes before any other locks.
406         total_consistency_lock: RwLock<()>,
407
408         keys_manager: K,
409
410         logger: Arc<Logger>,
411 }
412
413 /// The amount of time we require our counterparty wait to claim their money (ie time between when
414 /// we, or our watchtower, must check for them having broadcast a theft transaction).
415 pub(crate) const BREAKDOWN_TIMEOUT: u16 = 6 * 24;
416 /// The amount of time we're willing to wait to claim money back to us
417 pub(crate) const MAX_LOCAL_BREAKDOWN_TIMEOUT: u16 = 6 * 24 * 7;
418
419 /// The minimum number of blocks between an inbound HTLC's CLTV and the corresponding outbound
420 /// HTLC's CLTV. This should always be a few blocks greater than channelmonitor::CLTV_CLAIM_BUFFER,
421 /// ie the node we forwarded the payment on to should always have enough room to reliably time out
422 /// the HTLC via a full update_fail_htlc/commitment_signed dance before we hit the
423 /// CLTV_CLAIM_BUFFER point (we static assert that it's at least 3 blocks more).
424 const CLTV_EXPIRY_DELTA: u16 = 6 * 12; //TODO?
425 pub(super) const CLTV_FAR_FAR_AWAY: u32 = 6 * 24 * 7; //TODO?
426
427 // Check that our CLTV_EXPIRY is at least CLTV_CLAIM_BUFFER + ANTI_REORG_DELAY + LATENCY_GRACE_PERIOD_BLOCKS,
428 // ie that if the next-hop peer fails the HTLC within
429 // LATENCY_GRACE_PERIOD_BLOCKS then we'll still have CLTV_CLAIM_BUFFER left to timeout it onchain,
430 // then waiting ANTI_REORG_DELAY to be reorg-safe on the outbound HLTC and
431 // failing the corresponding htlc backward, and us now seeing the last block of ANTI_REORG_DELAY before
432 // LATENCY_GRACE_PERIOD_BLOCKS.
433 #[deny(const_err)]
434 #[allow(dead_code)]
435 const CHECK_CLTV_EXPIRY_SANITY: u32 = CLTV_EXPIRY_DELTA as u32 - LATENCY_GRACE_PERIOD_BLOCKS - CLTV_CLAIM_BUFFER - ANTI_REORG_DELAY - LATENCY_GRACE_PERIOD_BLOCKS;
436
437 // Check for ability of an attacker to make us fail on-chain by delaying inbound claim. See
438 // ChannelMontior::would_broadcast_at_height for a description of why this is needed.
439 #[deny(const_err)]
440 #[allow(dead_code)]
441 const CHECK_CLTV_EXPIRY_SANITY_2: u32 = CLTV_EXPIRY_DELTA as u32 - LATENCY_GRACE_PERIOD_BLOCKS - 2*CLTV_CLAIM_BUFFER;
442
443 macro_rules! secp_call {
444         ( $res: expr, $err: expr ) => {
445                 match $res {
446                         Ok(key) => key,
447                         Err(_) => return Err($err),
448                 }
449         };
450 }
451
452 /// Details of a channel, as returned by ChannelManager::list_channels and ChannelManager::list_usable_channels
453 pub struct ChannelDetails {
454         /// The channel's ID (prior to funding transaction generation, this is a random 32 bytes,
455         /// thereafter this is the txid of the funding transaction xor the funding transaction output).
456         /// Note that this means this value is *not* persistent - it can change once during the
457         /// lifetime of the channel.
458         pub channel_id: [u8; 32],
459         /// The position of the funding transaction in the chain. None if the funding transaction has
460         /// not yet been confirmed and the channel fully opened.
461         pub short_channel_id: Option<u64>,
462         /// The node_id of our counterparty
463         pub remote_network_id: PublicKey,
464         /// The Features the channel counterparty provided upon last connection.
465         /// Useful for routing as it is the most up-to-date copy of the counterparty's features and
466         /// many routing-relevant features are present in the init context.
467         pub counterparty_features: InitFeatures,
468         /// The value, in satoshis, of this channel as appears in the funding output
469         pub channel_value_satoshis: u64,
470         /// The user_id passed in to create_channel, or 0 if the channel was inbound.
471         pub user_id: u64,
472         /// The available outbound capacity for sending HTLCs to the remote peer. This does not include
473         /// any pending HTLCs which are not yet fully resolved (and, thus, who's balance is not
474         /// available for inclusion in new outbound HTLCs). This further does not include any pending
475         /// outgoing HTLCs which are awaiting some other resolution to be sent.
476         pub outbound_capacity_msat: u64,
477         /// The available inbound capacity for the remote peer to send HTLCs to us. This does not
478         /// include any pending HTLCs which are not yet fully resolved (and, thus, who's balance is not
479         /// available for inclusion in new inbound HTLCs).
480         /// Note that there are some corner cases not fully handled here, so the actual available
481         /// inbound capacity may be slightly higher than this.
482         pub inbound_capacity_msat: u64,
483         /// True if the channel is (a) confirmed and funding_locked messages have been exchanged, (b)
484         /// the peer is connected, and (c) no monitor update failure is pending resolution.
485         pub is_live: bool,
486 }
487
488 macro_rules! handle_error {
489         ($self: ident, $internal: expr, $their_node_id: expr) => {
490                 match $internal {
491                         Ok(msg) => Ok(msg),
492                         Err(MsgHandleErrInternal { err, shutdown_finish }) => {
493                                 #[cfg(debug_assertions)]
494                                 {
495                                         // In testing, ensure there are no deadlocks where the lock is already held upon
496                                         // entering the macro.
497                                         assert!($self.channel_state.try_lock().is_ok());
498                                 }
499
500                                 let mut msg_events = Vec::with_capacity(2);
501
502                                 if let Some((shutdown_res, update_option)) = shutdown_finish {
503                                         $self.finish_force_close_channel(shutdown_res);
504                                         if let Some(update) = update_option {
505                                                 msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
506                                                         msg: update
507                                                 });
508                                         }
509                                 }
510
511                                 log_error!($self, "{}", err.err);
512                                 if let msgs::ErrorAction::IgnoreError = err.action {
513                                 } else {
514                                         msg_events.push(events::MessageSendEvent::HandleError {
515                                                 node_id: $their_node_id,
516                                                 action: err.action.clone()
517                                         });
518                                 }
519
520                                 if !msg_events.is_empty() {
521                                         $self.channel_state.lock().unwrap().pending_msg_events.append(&mut msg_events);
522                                 }
523
524                                 // Return error in case higher-API need one
525                                 Err(err)
526                         },
527                 }
528         }
529 }
530
531 macro_rules! break_chan_entry {
532         ($self: ident, $res: expr, $channel_state: expr, $entry: expr) => {
533                 match $res {
534                         Ok(res) => res,
535                         Err(ChannelError::Ignore(msg)) => {
536                                 break Err(MsgHandleErrInternal::from_chan_no_close(ChannelError::Ignore(msg), $entry.key().clone()))
537                         },
538                         Err(ChannelError::Close(msg)) => {
539                                 log_trace!($self, "Closing channel {} due to Close-required error: {}", log_bytes!($entry.key()[..]), msg);
540                                 let (channel_id, mut chan) = $entry.remove_entry();
541                                 if let Some(short_id) = chan.get_short_channel_id() {
542                                         $channel_state.short_to_id.remove(&short_id);
543                                 }
544                                 break Err(MsgHandleErrInternal::from_finish_shutdown(msg, channel_id, chan.force_shutdown(true), $self.get_channel_update(&chan).ok())) },
545                         Err(ChannelError::CloseDelayBroadcast { .. }) => { panic!("Wait is only generated on receipt of channel_reestablish, which is handled by try_chan_entry, we don't bother to support it here"); }
546                 }
547         }
548 }
549
550 macro_rules! try_chan_entry {
551         ($self: ident, $res: expr, $channel_state: expr, $entry: expr) => {
552                 match $res {
553                         Ok(res) => res,
554                         Err(ChannelError::Ignore(msg)) => {
555                                 return Err(MsgHandleErrInternal::from_chan_no_close(ChannelError::Ignore(msg), $entry.key().clone()))
556                         },
557                         Err(ChannelError::Close(msg)) => {
558                                 log_trace!($self, "Closing channel {} due to Close-required error: {}", log_bytes!($entry.key()[..]), msg);
559                                 let (channel_id, mut chan) = $entry.remove_entry();
560                                 if let Some(short_id) = chan.get_short_channel_id() {
561                                         $channel_state.short_to_id.remove(&short_id);
562                                 }
563                                 return Err(MsgHandleErrInternal::from_finish_shutdown(msg, channel_id, chan.force_shutdown(true), $self.get_channel_update(&chan).ok()))
564                         },
565                         Err(ChannelError::CloseDelayBroadcast { msg, update }) => {
566                                 log_error!($self, "Channel {} need to be shutdown but closing transactions not broadcast due to {}", log_bytes!($entry.key()[..]), msg);
567                                 let (channel_id, mut chan) = $entry.remove_entry();
568                                 if let Some(short_id) = chan.get_short_channel_id() {
569                                         $channel_state.short_to_id.remove(&short_id);
570                                 }
571                                 if let Err(e) = $self.monitor.update_monitor(chan.get_funding_txo().unwrap(), update) {
572                                         match e {
573                                                 // Upstream channel is dead, but we want at least to fail backward HTLCs to save
574                                                 // downstream channels. In case of PermanentFailure, we are not going to be able
575                                                 // to claim back to_remote output on remote commitment transaction. Doesn't
576                                                 // make a difference here, we are concern about HTLCs circuit, not onchain funds.
577                                                 ChannelMonitorUpdateErr::PermanentFailure => {},
578                                                 ChannelMonitorUpdateErr::TemporaryFailure => {},
579                                         }
580                                 }
581                                 let shutdown_res = chan.force_shutdown(false);
582                                 return Err(MsgHandleErrInternal::from_finish_shutdown(msg, channel_id, shutdown_res, $self.get_channel_update(&chan).ok()))
583                         }
584                 }
585         }
586 }
587
588 macro_rules! handle_monitor_err {
589         ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $resend_raa: expr, $resend_commitment: expr) => {
590                 handle_monitor_err!($self, $err, $channel_state, $entry, $action_type, $resend_raa, $resend_commitment, Vec::new(), Vec::new())
591         };
592         ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $resend_raa: expr, $resend_commitment: expr, $failed_forwards: expr, $failed_fails: expr) => {
593                 match $err {
594                         ChannelMonitorUpdateErr::PermanentFailure => {
595                                 log_error!($self, "Closing channel {} due to monitor update PermanentFailure", log_bytes!($entry.key()[..]));
596                                 let (channel_id, mut chan) = $entry.remove_entry();
597                                 if let Some(short_id) = chan.get_short_channel_id() {
598                                         $channel_state.short_to_id.remove(&short_id);
599                                 }
600                                 // TODO: $failed_fails is dropped here, which will cause other channels to hit the
601                                 // chain in a confused state! We need to move them into the ChannelMonitor which
602                                 // will be responsible for failing backwards once things confirm on-chain.
603                                 // It's ok that we drop $failed_forwards here - at this point we'd rather they
604                                 // broadcast HTLC-Timeout and pay the associated fees to get their funds back than
605                                 // us bother trying to claim it just to forward on to another peer. If we're
606                                 // splitting hairs we'd prefer to claim payments that were to us, but we haven't
607                                 // given up the preimage yet, so might as well just wait until the payment is
608                                 // retried, avoiding the on-chain fees.
609                                 let res: Result<(), _> = Err(MsgHandleErrInternal::from_finish_shutdown("ChannelMonitor storage failure", channel_id, chan.force_shutdown(true), $self.get_channel_update(&chan).ok()));
610                                 res
611                         },
612                         ChannelMonitorUpdateErr::TemporaryFailure => {
613                                 log_info!($self, "Disabling channel {} due to monitor update TemporaryFailure. On restore will send {} and process {} forwards and {} fails",
614                                                 log_bytes!($entry.key()[..]),
615                                                 if $resend_commitment && $resend_raa {
616                                                                 match $action_type {
617                                                                         RAACommitmentOrder::CommitmentFirst => { "commitment then RAA" },
618                                                                         RAACommitmentOrder::RevokeAndACKFirst => { "RAA then commitment" },
619                                                                 }
620                                                         } else if $resend_commitment { "commitment" }
621                                                         else if $resend_raa { "RAA" }
622                                                         else { "nothing" },
623                                                 (&$failed_forwards as &Vec<(PendingHTLCInfo, u64)>).len(),
624                                                 (&$failed_fails as &Vec<(HTLCSource, PaymentHash, HTLCFailReason)>).len());
625                                 if !$resend_commitment {
626                                         debug_assert!($action_type == RAACommitmentOrder::RevokeAndACKFirst || !$resend_raa);
627                                 }
628                                 if !$resend_raa {
629                                         debug_assert!($action_type == RAACommitmentOrder::CommitmentFirst || !$resend_commitment);
630                                 }
631                                 $entry.get_mut().monitor_update_failed($resend_raa, $resend_commitment, $failed_forwards, $failed_fails);
632                                 Err(MsgHandleErrInternal::from_chan_no_close(ChannelError::Ignore("Failed to update ChannelMonitor"), *$entry.key()))
633                         },
634                 }
635         }
636 }
637
638 macro_rules! return_monitor_err {
639         ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $resend_raa: expr, $resend_commitment: expr) => {
640                 return handle_monitor_err!($self, $err, $channel_state, $entry, $action_type, $resend_raa, $resend_commitment);
641         };
642         ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $resend_raa: expr, $resend_commitment: expr, $failed_forwards: expr, $failed_fails: expr) => {
643                 return handle_monitor_err!($self, $err, $channel_state, $entry, $action_type, $resend_raa, $resend_commitment, $failed_forwards, $failed_fails);
644         }
645 }
646
647 // Does not break in case of TemporaryFailure!
648 macro_rules! maybe_break_monitor_err {
649         ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $resend_raa: expr, $resend_commitment: expr) => {
650                 match (handle_monitor_err!($self, $err, $channel_state, $entry, $action_type, $resend_raa, $resend_commitment), $err) {
651                         (e, ChannelMonitorUpdateErr::PermanentFailure) => {
652                                 break e;
653                         },
654                         (_, ChannelMonitorUpdateErr::TemporaryFailure) => { },
655                 }
656         }
657 }
658
659 impl<ChanSigner: ChannelKeys, M: Deref, T: Deref, K: Deref, F: Deref> ChannelManager<ChanSigner, M, T, K, F>
660         where M::Target: ManyChannelMonitor<ChanSigner>,
661         T::Target: BroadcasterInterface,
662         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
663         F::Target: FeeEstimator,
664 {
665         /// Constructs a new ChannelManager to hold several channels and route between them.
666         ///
667         /// This is the main "logic hub" for all channel-related actions, and implements
668         /// ChannelMessageHandler.
669         ///
670         /// Non-proportional fees are fixed according to our risk using the provided fee estimator.
671         ///
672         /// panics if channel_value_satoshis is >= `MAX_FUNDING_SATOSHIS`!
673         ///
674         /// Users must provide the current blockchain height from which to track onchain channel
675         /// funding outpoints and send payments with reliable timelocks.
676         ///
677         /// Users need to notify the new ChannelManager when a new block is connected or
678         /// disconnected using its `block_connected` and `block_disconnected` methods.
679         /// However, rather than calling these methods directly, the user should register
680         /// the ChannelManager as a listener to the BlockNotifier and call the BlockNotifier's
681         /// `block_(dis)connected` methods, which will notify all registered listeners in one
682         /// go.
683         pub fn new(network: Network, fee_est: F, monitor: M, tx_broadcaster: T, logger: Arc<Logger>, keys_manager: K, config: UserConfig, current_blockchain_height: usize) -> Result<ChannelManager<ChanSigner, M, T, K, F>, secp256k1::Error> {
684                 let secp_ctx = Secp256k1::new();
685
686                 let res = ChannelManager {
687                         default_configuration: config.clone(),
688                         genesis_hash: genesis_block(network).header.bitcoin_hash(),
689                         fee_estimator: fee_est,
690                         monitor,
691                         tx_broadcaster,
692
693                         latest_block_height: AtomicUsize::new(current_blockchain_height),
694                         last_block_hash: Mutex::new(Default::default()),
695                         secp_ctx,
696
697                         channel_state: Mutex::new(ChannelHolder{
698                                 by_id: HashMap::new(),
699                                 short_to_id: HashMap::new(),
700                                 forward_htlcs: HashMap::new(),
701                                 claimable_htlcs: HashMap::new(),
702                                 pending_msg_events: Vec::new(),
703                         }),
704                         our_network_key: keys_manager.get_node_secret(),
705
706                         last_node_announcement_serial: AtomicUsize::new(0),
707
708                         per_peer_state: RwLock::new(HashMap::new()),
709
710                         pending_events: Mutex::new(Vec::new()),
711                         total_consistency_lock: RwLock::new(()),
712
713                         keys_manager,
714
715                         logger,
716                 };
717
718                 Ok(res)
719         }
720
721         /// Creates a new outbound channel to the given remote node and with the given value.
722         ///
723         /// user_id will be provided back as user_channel_id in FundingGenerationReady and
724         /// FundingBroadcastSafe events to allow tracking of which events correspond with which
725         /// create_channel call. Note that user_channel_id defaults to 0 for inbound channels, so you
726         /// may wish to avoid using 0 for user_id here.
727         ///
728         /// If successful, will generate a SendOpenChannel message event, so you should probably poll
729         /// PeerManager::process_events afterwards.
730         ///
731         /// Raises APIError::APIMisuseError when channel_value_satoshis > 2**24 or push_msat is
732         /// greater than channel_value_satoshis * 1k or channel_value_satoshis is < 1000.
733         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> {
734                 if channel_value_satoshis < 1000 {
735                         return Err(APIError::APIMisuseError { err: "channel_value must be at least 1000 satoshis" });
736                 }
737
738                 let config = if override_config.is_some() { override_config.as_ref().unwrap() } else { &self.default_configuration };
739                 let channel = Channel::new_outbound(&self.fee_estimator, &self.keys_manager, their_network_key, channel_value_satoshis, push_msat, user_id, Arc::clone(&self.logger), config)?;
740                 let res = channel.get_open_channel(self.genesis_hash.clone(), &self.fee_estimator);
741
742                 let _ = self.total_consistency_lock.read().unwrap();
743                 let mut channel_state = self.channel_state.lock().unwrap();
744                 match channel_state.by_id.entry(channel.channel_id()) {
745                         hash_map::Entry::Occupied(_) => {
746                                 if cfg!(feature = "fuzztarget") {
747                                         return Err(APIError::APIMisuseError { err: "Fuzzy bad RNG" });
748                                 } else {
749                                         panic!("RNG is bad???");
750                                 }
751                         },
752                         hash_map::Entry::Vacant(entry) => { entry.insert(channel); }
753                 }
754                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendOpenChannel {
755                         node_id: their_network_key,
756                         msg: res,
757                 });
758                 Ok(())
759         }
760
761         fn list_channels_with_filter<Fn: FnMut(&(&[u8; 32], &Channel<ChanSigner>)) -> bool>(&self, f: Fn) -> Vec<ChannelDetails> {
762                 let mut res = Vec::new();
763                 {
764                         let channel_state = self.channel_state.lock().unwrap();
765                         res.reserve(channel_state.by_id.len());
766                         for (channel_id, channel) in channel_state.by_id.iter().filter(f) {
767                                 let (inbound_capacity_msat, outbound_capacity_msat) = channel.get_inbound_outbound_available_balance_msat();
768                                 res.push(ChannelDetails {
769                                         channel_id: (*channel_id).clone(),
770                                         short_channel_id: channel.get_short_channel_id(),
771                                         remote_network_id: channel.get_their_node_id(),
772                                         counterparty_features: InitFeatures::empty(),
773                                         channel_value_satoshis: channel.get_value_satoshis(),
774                                         inbound_capacity_msat,
775                                         outbound_capacity_msat,
776                                         user_id: channel.get_user_id(),
777                                         is_live: channel.is_live(),
778                                 });
779                         }
780                 }
781                 let per_peer_state = self.per_peer_state.read().unwrap();
782                 for chan in res.iter_mut() {
783                         if let Some(peer_state) = per_peer_state.get(&chan.remote_network_id) {
784                                 chan.counterparty_features = peer_state.lock().unwrap().latest_features.clone();
785                         }
786                 }
787                 res
788         }
789
790         /// Gets the list of open channels, in random order. See ChannelDetail field documentation for
791         /// more information.
792         pub fn list_channels(&self) -> Vec<ChannelDetails> {
793                 self.list_channels_with_filter(|_| true)
794         }
795
796         /// Gets the list of usable channels, in random order. Useful as an argument to
797         /// Router::get_route to ensure non-announced channels are used.
798         ///
799         /// These are guaranteed to have their is_live value set to true, see the documentation for
800         /// ChannelDetails::is_live for more info on exactly what the criteria are.
801         pub fn list_usable_channels(&self) -> Vec<ChannelDetails> {
802                 // Note we use is_live here instead of usable which leads to somewhat confused
803                 // internal/external nomenclature, but that's ok cause that's probably what the user
804                 // really wanted anyway.
805                 self.list_channels_with_filter(|&(_, ref channel)| channel.is_live())
806         }
807
808         /// Begins the process of closing a channel. After this call (plus some timeout), no new HTLCs
809         /// will be accepted on the given channel, and after additional timeout/the closing of all
810         /// pending HTLCs, the channel will be closed on chain.
811         ///
812         /// May generate a SendShutdown message event on success, which should be relayed.
813         pub fn close_channel(&self, channel_id: &[u8; 32]) -> Result<(), APIError> {
814                 let _ = self.total_consistency_lock.read().unwrap();
815
816                 let (mut failed_htlcs, chan_option) = {
817                         let mut channel_state_lock = self.channel_state.lock().unwrap();
818                         let channel_state = &mut *channel_state_lock;
819                         match channel_state.by_id.entry(channel_id.clone()) {
820                                 hash_map::Entry::Occupied(mut chan_entry) => {
821                                         let (shutdown_msg, failed_htlcs) = chan_entry.get_mut().get_shutdown()?;
822                                         channel_state.pending_msg_events.push(events::MessageSendEvent::SendShutdown {
823                                                 node_id: chan_entry.get().get_their_node_id(),
824                                                 msg: shutdown_msg
825                                         });
826                                         if chan_entry.get().is_shutdown() {
827                                                 if let Some(short_id) = chan_entry.get().get_short_channel_id() {
828                                                         channel_state.short_to_id.remove(&short_id);
829                                                 }
830                                                 (failed_htlcs, Some(chan_entry.remove_entry().1))
831                                         } else { (failed_htlcs, None) }
832                                 },
833                                 hash_map::Entry::Vacant(_) => return Err(APIError::ChannelUnavailable{err: "No such channel"})
834                         }
835                 };
836                 for htlc_source in failed_htlcs.drain(..) {
837                         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() });
838                 }
839                 let chan_update = if let Some(chan) = chan_option {
840                         if let Ok(update) = self.get_channel_update(&chan) {
841                                 Some(update)
842                         } else { None }
843                 } else { None };
844
845                 if let Some(update) = chan_update {
846                         let mut channel_state = self.channel_state.lock().unwrap();
847                         channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
848                                 msg: update
849                         });
850                 }
851
852                 Ok(())
853         }
854
855         #[inline]
856         fn finish_force_close_channel(&self, shutdown_res: ShutdownResult) {
857                 let (funding_txo_option, monitor_update, mut failed_htlcs) = shutdown_res;
858                 log_trace!(self, "Finishing force-closure of channel {} HTLCs to fail", failed_htlcs.len());
859                 for htlc_source in failed_htlcs.drain(..) {
860                         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() });
861                 }
862                 if let Some(funding_txo) = funding_txo_option {
863                         // There isn't anything we can do if we get an update failure - we're already
864                         // force-closing. The monitor update on the required in-memory copy should broadcast
865                         // the latest local state, which is the best we can do anyway. Thus, it is safe to
866                         // ignore the result here.
867                         let _ = self.monitor.update_monitor(funding_txo, monitor_update);
868                 }
869         }
870
871         /// Force closes a channel, immediately broadcasting the latest local commitment transaction to
872         /// the chain and rejecting new HTLCs on the given channel.
873         pub fn force_close_channel(&self, channel_id: &[u8; 32]) {
874                 let _ = self.total_consistency_lock.read().unwrap();
875
876                 let mut chan = {
877                         let mut channel_state_lock = self.channel_state.lock().unwrap();
878                         let channel_state = &mut *channel_state_lock;
879                         if let Some(chan) = channel_state.by_id.remove(channel_id) {
880                                 if let Some(short_id) = chan.get_short_channel_id() {
881                                         channel_state.short_to_id.remove(&short_id);
882                                 }
883                                 chan
884                         } else {
885                                 return;
886                         }
887                 };
888                 log_trace!(self, "Force-closing channel {}", log_bytes!(channel_id[..]));
889                 self.finish_force_close_channel(chan.force_shutdown(true));
890                 if let Ok(update) = self.get_channel_update(&chan) {
891                         let mut channel_state = self.channel_state.lock().unwrap();
892                         channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
893                                 msg: update
894                         });
895                 }
896         }
897
898         /// Force close all channels, immediately broadcasting the latest local commitment transaction
899         /// for each to the chain and rejecting new HTLCs on each.
900         pub fn force_close_all_channels(&self) {
901                 for chan in self.list_channels() {
902                         self.force_close_channel(&chan.channel_id);
903                 }
904         }
905
906         fn decode_update_add_htlc_onion(&self, msg: &msgs::UpdateAddHTLC) -> (PendingHTLCStatus, MutexGuard<ChannelHolder<ChanSigner>>) {
907                 macro_rules! return_malformed_err {
908                         ($msg: expr, $err_code: expr) => {
909                                 {
910                                         log_info!(self, "Failed to accept/forward incoming HTLC: {}", $msg);
911                                         return (PendingHTLCStatus::Fail(HTLCFailureMsg::Malformed(msgs::UpdateFailMalformedHTLC {
912                                                 channel_id: msg.channel_id,
913                                                 htlc_id: msg.htlc_id,
914                                                 sha256_of_onion: Sha256::hash(&msg.onion_routing_packet.hop_data).into_inner(),
915                                                 failure_code: $err_code,
916                                         })), self.channel_state.lock().unwrap());
917                                 }
918                         }
919                 }
920
921                 if let Err(_) = msg.onion_routing_packet.public_key {
922                         return_malformed_err!("invalid ephemeral pubkey", 0x8000 | 0x4000 | 6);
923                 }
924
925                 let shared_secret = {
926                         let mut arr = [0; 32];
927                         arr.copy_from_slice(&SharedSecret::new(&msg.onion_routing_packet.public_key.unwrap(), &self.our_network_key)[..]);
928                         arr
929                 };
930                 let (rho, mu) = onion_utils::gen_rho_mu_from_shared_secret(&shared_secret);
931
932                 if msg.onion_routing_packet.version != 0 {
933                         //TODO: Spec doesn't indicate if we should only hash hop_data here (and in other
934                         //sha256_of_onion error data packets), or the entire onion_routing_packet. Either way,
935                         //the hash doesn't really serve any purpose - in the case of hashing all data, the
936                         //receiving node would have to brute force to figure out which version was put in the
937                         //packet by the node that send us the message, in the case of hashing the hop_data, the
938                         //node knows the HMAC matched, so they already know what is there...
939                         return_malformed_err!("Unknown onion packet version", 0x8000 | 0x4000 | 4);
940                 }
941
942                 let mut hmac = HmacEngine::<Sha256>::new(&mu);
943                 hmac.input(&msg.onion_routing_packet.hop_data);
944                 hmac.input(&msg.payment_hash.0[..]);
945                 if !fixed_time_eq(&Hmac::from_engine(hmac).into_inner(), &msg.onion_routing_packet.hmac) {
946                         return_malformed_err!("HMAC Check failed", 0x8000 | 0x4000 | 5);
947                 }
948
949                 let mut channel_state = None;
950                 macro_rules! return_err {
951                         ($msg: expr, $err_code: expr, $data: expr) => {
952                                 {
953                                         log_info!(self, "Failed to accept/forward incoming HTLC: {}", $msg);
954                                         if channel_state.is_none() {
955                                                 channel_state = Some(self.channel_state.lock().unwrap());
956                                         }
957                                         return (PendingHTLCStatus::Fail(HTLCFailureMsg::Relay(msgs::UpdateFailHTLC {
958                                                 channel_id: msg.channel_id,
959                                                 htlc_id: msg.htlc_id,
960                                                 reason: onion_utils::build_first_hop_failure_packet(&shared_secret, $err_code, $data),
961                                         })), channel_state.unwrap());
962                                 }
963                         }
964                 }
965
966                 let mut chacha = ChaCha20::new(&rho, &[0u8; 8]);
967                 let mut chacha_stream = ChaChaReader { chacha: &mut chacha, read: Cursor::new(&msg.onion_routing_packet.hop_data[..]) };
968                 let (next_hop_data, next_hop_hmac) = {
969                         match msgs::OnionHopData::read(&mut chacha_stream) {
970                                 Err(err) => {
971                                         let error_code = match err {
972                                                 msgs::DecodeError::UnknownVersion => 0x4000 | 1, // unknown realm byte
973                                                 msgs::DecodeError::UnknownRequiredFeature|
974                                                 msgs::DecodeError::InvalidValue|
975                                                 msgs::DecodeError::ShortRead => 0x4000 | 22, // invalid_onion_payload
976                                                 _ => 0x2000 | 2, // Should never happen
977                                         };
978                                         return_err!("Unable to decode our hop data", error_code, &[0;0]);
979                                 },
980                                 Ok(msg) => {
981                                         let mut hmac = [0; 32];
982                                         if let Err(_) = chacha_stream.read_exact(&mut hmac[..]) {
983                                                 return_err!("Unable to decode hop data", 0x4000 | 22, &[0;0]);
984                                         }
985                                         (msg, hmac)
986                                 },
987                         }
988                 };
989
990                 let pending_forward_info = if next_hop_hmac == [0; 32] {
991                                 #[cfg(test)]
992                                 {
993                                         // In tests, make sure that the initial onion pcket data is, at least, non-0.
994                                         // We could do some fancy randomness test here, but, ehh, whatever.
995                                         // This checks for the issue where you can calculate the path length given the
996                                         // onion data as all the path entries that the originator sent will be here
997                                         // as-is (and were originally 0s).
998                                         // Of course reverse path calculation is still pretty easy given naive routing
999                                         // algorithms, but this fixes the most-obvious case.
1000                                         let mut next_bytes = [0; 32];
1001                                         chacha_stream.read_exact(&mut next_bytes).unwrap();
1002                                         assert_ne!(next_bytes[..], [0; 32][..]);
1003                                         chacha_stream.read_exact(&mut next_bytes).unwrap();
1004                                         assert_ne!(next_bytes[..], [0; 32][..]);
1005                                 }
1006
1007                                 // OUR PAYMENT!
1008                                 // final_expiry_too_soon
1009                                 if (msg.cltv_expiry as u64) < self.latest_block_height.load(Ordering::Acquire) as u64 + (CLTV_CLAIM_BUFFER + LATENCY_GRACE_PERIOD_BLOCKS) as u64 {
1010                                         return_err!("The final CLTV expiry is too soon to handle", 17, &[0;0]);
1011                                 }
1012                                 // final_incorrect_htlc_amount
1013                                 if next_hop_data.amt_to_forward > msg.amount_msat {
1014                                         return_err!("Upstream node sent less than we were supposed to receive in payment", 19, &byte_utils::be64_to_array(msg.amount_msat));
1015                                 }
1016                                 // final_incorrect_cltv_expiry
1017                                 if next_hop_data.outgoing_cltv_value != msg.cltv_expiry {
1018                                         return_err!("Upstream node set CLTV to the wrong value", 18, &byte_utils::be32_to_array(msg.cltv_expiry));
1019                                 }
1020
1021                                 let payment_data = match next_hop_data.format {
1022                                         msgs::OnionHopDataFormat::Legacy { .. } => None,
1023                                         msgs::OnionHopDataFormat::NonFinalNode { .. } => return_err!("Got non final data with an HMAC of 0", 0x4000 | 22, &[0;0]),
1024                                         msgs::OnionHopDataFormat::FinalNode { payment_data } => payment_data,
1025                                 };
1026
1027                                 // Note that we could obviously respond immediately with an update_fulfill_htlc
1028                                 // message, however that would leak that we are the recipient of this payment, so
1029                                 // instead we stay symmetric with the forwarding case, only responding (after a
1030                                 // delay) once they've send us a commitment_signed!
1031
1032                                 PendingHTLCStatus::Forward(PendingHTLCInfo {
1033                                         routing: PendingHTLCRouting::Receive { payment_data },
1034                                         payment_hash: msg.payment_hash.clone(),
1035                                         incoming_shared_secret: shared_secret,
1036                                         amt_to_forward: next_hop_data.amt_to_forward,
1037                                         outgoing_cltv_value: next_hop_data.outgoing_cltv_value,
1038                                 })
1039                         } else {
1040                                 let mut new_packet_data = [0; 20*65];
1041                                 let read_pos = chacha_stream.read(&mut new_packet_data).unwrap();
1042                                 #[cfg(debug_assertions)]
1043                                 {
1044                                         // Check two things:
1045                                         // a) that the behavior of our stream here will return Ok(0) even if the TLV
1046                                         //    read above emptied out our buffer and the unwrap() wont needlessly panic
1047                                         // b) that we didn't somehow magically end up with extra data.
1048                                         let mut t = [0; 1];
1049                                         debug_assert!(chacha_stream.read(&mut t).unwrap() == 0);
1050                                 }
1051                                 // Once we've emptied the set of bytes our peer gave us, encrypt 0 bytes until we
1052                                 // fill the onion hop data we'll forward to our next-hop peer.
1053                                 chacha_stream.chacha.process_in_place(&mut new_packet_data[read_pos..]);
1054
1055                                 let mut new_pubkey = msg.onion_routing_packet.public_key.unwrap();
1056
1057                                 let blinding_factor = {
1058                                         let mut sha = Sha256::engine();
1059                                         sha.input(&new_pubkey.serialize()[..]);
1060                                         sha.input(&shared_secret);
1061                                         Sha256::from_engine(sha).into_inner()
1062                                 };
1063
1064                                 let public_key = if let Err(e) = new_pubkey.mul_assign(&self.secp_ctx, &blinding_factor[..]) {
1065                                         Err(e)
1066                                 } else { Ok(new_pubkey) };
1067
1068                                 let outgoing_packet = msgs::OnionPacket {
1069                                         version: 0,
1070                                         public_key,
1071                                         hop_data: new_packet_data,
1072                                         hmac: next_hop_hmac.clone(),
1073                                 };
1074
1075                                 let short_channel_id = match next_hop_data.format {
1076                                         msgs::OnionHopDataFormat::Legacy { short_channel_id } => short_channel_id,
1077                                         msgs::OnionHopDataFormat::NonFinalNode { short_channel_id } => short_channel_id,
1078                                         msgs::OnionHopDataFormat::FinalNode { .. } => {
1079                                                 return_err!("Final Node OnionHopData provided for us as an intermediary node", 0x4000 | 22, &[0;0]);
1080                                         },
1081                                 };
1082
1083                                 PendingHTLCStatus::Forward(PendingHTLCInfo {
1084                                         routing: PendingHTLCRouting::Forward {
1085                                                 onion_packet: outgoing_packet,
1086                                                 short_channel_id: short_channel_id,
1087                                         },
1088                                         payment_hash: msg.payment_hash.clone(),
1089                                         incoming_shared_secret: shared_secret,
1090                                         amt_to_forward: next_hop_data.amt_to_forward,
1091                                         outgoing_cltv_value: next_hop_data.outgoing_cltv_value,
1092                                 })
1093                         };
1094
1095                 channel_state = Some(self.channel_state.lock().unwrap());
1096                 if let &PendingHTLCStatus::Forward(PendingHTLCInfo { ref routing, ref amt_to_forward, ref outgoing_cltv_value, .. }) = &pending_forward_info {
1097                         // If short_channel_id is 0 here, we'll reject the HTLC as there cannot be a channel
1098                         // with a short_channel_id of 0. This is important as various things later assume
1099                         // short_channel_id is non-0 in any ::Forward.
1100                         if let &PendingHTLCRouting::Forward { ref short_channel_id, .. } = routing {
1101                                 let id_option = channel_state.as_ref().unwrap().short_to_id.get(&short_channel_id).cloned();
1102                                 let forwarding_id = match id_option {
1103                                         None => { // unknown_next_peer
1104                                                 return_err!("Don't have available channel for forwarding as requested.", 0x4000 | 10, &[0;0]);
1105                                         },
1106                                         Some(id) => id.clone(),
1107                                 };
1108                                 if let Some((err, code, chan_update)) = loop {
1109                                         let chan = channel_state.as_mut().unwrap().by_id.get_mut(&forwarding_id).unwrap();
1110
1111                                         // Note that we could technically not return an error yet here and just hope
1112                                         // that the connection is reestablished or monitor updated by the time we get
1113                                         // around to doing the actual forward, but better to fail early if we can and
1114                                         // hopefully an attacker trying to path-trace payments cannot make this occur
1115                                         // on a small/per-node/per-channel scale.
1116                                         if !chan.is_live() { // channel_disabled
1117                                                 break Some(("Forwarding channel is not in a ready state.", 0x1000 | 20, Some(self.get_channel_update(chan).unwrap())));
1118                                         }
1119                                         if *amt_to_forward < chan.get_their_htlc_minimum_msat() { // amount_below_minimum
1120                                                 break Some(("HTLC amount was below the htlc_minimum_msat", 0x1000 | 11, Some(self.get_channel_update(chan).unwrap())));
1121                                         }
1122                                         let fee = amt_to_forward.checked_mul(chan.get_fee_proportional_millionths() as u64).and_then(|prop_fee| { (prop_fee / 1000000).checked_add(chan.get_our_fee_base_msat(&self.fee_estimator) as u64) });
1123                                         if fee.is_none() || msg.amount_msat < fee.unwrap() || (msg.amount_msat - fee.unwrap()) < *amt_to_forward { // fee_insufficient
1124                                                 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())));
1125                                         }
1126                                         if (msg.cltv_expiry as u64) < (*outgoing_cltv_value) as u64 + CLTV_EXPIRY_DELTA as u64 { // incorrect_cltv_expiry
1127                                                 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())));
1128                                         }
1129                                         let cur_height = self.latest_block_height.load(Ordering::Acquire) as u32 + 1;
1130                                         // We want to have at least LATENCY_GRACE_PERIOD_BLOCKS to fail prior to going on chain CLAIM_BUFFER blocks before expiration
1131                                         if msg.cltv_expiry <= cur_height + CLTV_CLAIM_BUFFER + LATENCY_GRACE_PERIOD_BLOCKS as u32 { // expiry_too_soon
1132                                                 break Some(("CLTV expiry is too close", 0x1000 | 14, Some(self.get_channel_update(chan).unwrap())));
1133                                         }
1134                                         if msg.cltv_expiry > cur_height + CLTV_FAR_FAR_AWAY as u32 { // expiry_too_far
1135                                                 break Some(("CLTV expiry is too far in the future", 21, None));
1136                                         }
1137                                         break None;
1138                                 }
1139                                 {
1140                                         let mut res = Vec::with_capacity(8 + 128);
1141                                         if let Some(chan_update) = chan_update {
1142                                                 if code == 0x1000 | 11 || code == 0x1000 | 12 {
1143                                                         res.extend_from_slice(&byte_utils::be64_to_array(msg.amount_msat));
1144                                                 }
1145                                                 else if code == 0x1000 | 13 {
1146                                                         res.extend_from_slice(&byte_utils::be32_to_array(msg.cltv_expiry));
1147                                                 }
1148                                                 else if code == 0x1000 | 20 {
1149                                                         res.extend_from_slice(&byte_utils::be16_to_array(chan_update.contents.flags));
1150                                                 }
1151                                                 res.extend_from_slice(&chan_update.encode_with_len()[..]);
1152                                         }
1153                                         return_err!(err, code, &res[..]);
1154                                 }
1155                         }
1156                 }
1157
1158                 (pending_forward_info, channel_state.unwrap())
1159         }
1160
1161         /// only fails if the channel does not yet have an assigned short_id
1162         /// May be called with channel_state already locked!
1163         fn get_channel_update(&self, chan: &Channel<ChanSigner>) -> Result<msgs::ChannelUpdate, LightningError> {
1164                 let short_channel_id = match chan.get_short_channel_id() {
1165                         None => return Err(LightningError{err: "Channel not yet established", action: msgs::ErrorAction::IgnoreError}),
1166                         Some(id) => id,
1167                 };
1168
1169                 let were_node_one = PublicKey::from_secret_key(&self.secp_ctx, &self.our_network_key).serialize()[..] < chan.get_their_node_id().serialize()[..];
1170
1171                 let unsigned = msgs::UnsignedChannelUpdate {
1172                         chain_hash: self.genesis_hash,
1173                         short_channel_id: short_channel_id,
1174                         timestamp: chan.get_update_time_counter(),
1175                         flags: (!were_node_one) as u16 | ((!chan.is_live() as u16) << 1),
1176                         cltv_expiry_delta: CLTV_EXPIRY_DELTA,
1177                         htlc_minimum_msat: chan.get_our_htlc_minimum_msat(),
1178                         fee_base_msat: chan.get_our_fee_base_msat(&self.fee_estimator),
1179                         fee_proportional_millionths: chan.get_fee_proportional_millionths(),
1180                         excess_data: Vec::new(),
1181                 };
1182
1183                 let msg_hash = Sha256dHash::hash(&unsigned.encode()[..]);
1184                 let sig = self.secp_ctx.sign(&hash_to_message!(&msg_hash[..]), &self.our_network_key);
1185
1186                 Ok(msgs::ChannelUpdate {
1187                         signature: sig,
1188                         contents: unsigned
1189                 })
1190         }
1191
1192         /// Sends a payment along a given route.
1193         ///
1194         /// Value parameters are provided via the last hop in route, see documentation for RouteHop
1195         /// fields for more info.
1196         ///
1197         /// Note that if the payment_hash already exists elsewhere (eg you're sending a duplicative
1198         /// payment), we don't do anything to stop you! We always try to ensure that if the provided
1199         /// next hop knows the preimage to payment_hash they can claim an additional amount as
1200         /// specified in the last hop in the route! Thus, you should probably do your own
1201         /// payment_preimage tracking (which you should already be doing as they represent "proof of
1202         /// payment") and prevent double-sends yourself.
1203         ///
1204         /// May generate a SendHTLCs message event on success, which should be relayed.
1205         ///
1206         /// Raises APIError::RoutError when invalid route or forward parameter
1207         /// (cltv_delta, fee, node public key) is specified.
1208         /// Raises APIError::ChannelUnavailable if the next-hop channel is not available for updates
1209         /// (including due to previous monitor update failure or new permanent monitor update failure).
1210         /// Raised APIError::MonitorUpdateFailed if a new monitor update failure prevented sending the
1211         /// relevant updates.
1212         ///
1213         /// In case of APIError::RouteError/APIError::ChannelUnavailable, the payment send has failed
1214         /// and you may wish to retry via a different route immediately.
1215         /// In case of APIError::MonitorUpdateFailed, the commitment update has been irrevocably
1216         /// committed on our end and we're just waiting for a monitor update to send it. Do NOT retry
1217         /// the payment via a different route unless you intend to pay twice!
1218         pub fn send_payment(&self, route: Route, payment_hash: PaymentHash) -> Result<(), APIError> {
1219                 if route.hops.len() < 1 || route.hops.len() > 20 {
1220                         return Err(APIError::RouteError{err: "Route didn't go anywhere/had bogus size"});
1221                 }
1222                 let our_node_id = self.get_our_node_id();
1223                 for (idx, hop) in route.hops.iter().enumerate() {
1224                         if idx != route.hops.len() - 1 && hop.pubkey == our_node_id {
1225                                 return Err(APIError::RouteError{err: "Route went through us but wasn't a simple rebalance loop to us"});
1226                         }
1227                 }
1228
1229                 let (session_priv, prng_seed) = self.keys_manager.get_onion_rand();
1230
1231                 let cur_height = self.latest_block_height.load(Ordering::Acquire) as u32 + 1;
1232
1233                 let onion_keys = secp_call!(onion_utils::construct_onion_keys(&self.secp_ctx, &route, &session_priv),
1234                                 APIError::RouteError{err: "Pubkey along hop was maliciously selected"});
1235                 let (onion_payloads, htlc_msat, htlc_cltv) = onion_utils::build_onion_payloads(&route, cur_height)?;
1236                 if onion_utils::route_size_insane(&onion_payloads) {
1237                         return Err(APIError::RouteError{err: "Route size too large considering onion data"});
1238                 }
1239                 let onion_packet = onion_utils::construct_onion_packet(onion_payloads, onion_keys, prng_seed, &payment_hash);
1240
1241                 let _ = self.total_consistency_lock.read().unwrap();
1242
1243                 let err: Result<(), _> = loop {
1244                         let mut channel_lock = self.channel_state.lock().unwrap();
1245                         let id = match channel_lock.short_to_id.get(&route.hops.first().unwrap().short_channel_id) {
1246                                 None => return Err(APIError::ChannelUnavailable{err: "No channel available with first hop!"}),
1247                                 Some(id) => id.clone(),
1248                         };
1249
1250                         let channel_state = &mut *channel_lock;
1251                         if let hash_map::Entry::Occupied(mut chan) = channel_state.by_id.entry(id) {
1252                                 match {
1253                                         if chan.get().get_their_node_id() != route.hops.first().unwrap().pubkey {
1254                                                 return Err(APIError::RouteError{err: "Node ID mismatch on first hop!"});
1255                                         }
1256                                         if !chan.get().is_live() {
1257                                                 return Err(APIError::ChannelUnavailable{err: "Peer for first hop currently disconnected/pending monitor update!"});
1258                                         }
1259                                         break_chan_entry!(self, chan.get_mut().send_htlc_and_commit(htlc_msat, payment_hash.clone(), htlc_cltv, HTLCSource::OutboundRoute {
1260                                                 route: route.clone(),
1261                                                 session_priv: session_priv.clone(),
1262                                                 first_hop_htlc_msat: htlc_msat,
1263                                         }, onion_packet), channel_state, chan)
1264                                 } {
1265                                         Some((update_add, commitment_signed, monitor_update)) => {
1266                                                 if let Err(e) = self.monitor.update_monitor(chan.get().get_funding_txo().unwrap(), monitor_update) {
1267                                                         maybe_break_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::CommitmentFirst, false, true);
1268                                                         // Note that MonitorUpdateFailed here indicates (per function docs)
1269                                                         // that we will resent the commitment update once we unfree monitor
1270                                                         // updating, so we have to take special care that we don't return
1271                                                         // something else in case we will resend later!
1272                                                         return Err(APIError::MonitorUpdateFailed);
1273                                                 }
1274
1275                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
1276                                                         node_id: route.hops.first().unwrap().pubkey,
1277                                                         updates: msgs::CommitmentUpdate {
1278                                                                 update_add_htlcs: vec![update_add],
1279                                                                 update_fulfill_htlcs: Vec::new(),
1280                                                                 update_fail_htlcs: Vec::new(),
1281                                                                 update_fail_malformed_htlcs: Vec::new(),
1282                                                                 update_fee: None,
1283                                                                 commitment_signed,
1284                                                         },
1285                                                 });
1286                                         },
1287                                         None => {},
1288                                 }
1289                         } else { unreachable!(); }
1290                         return Ok(());
1291                 };
1292
1293                 match handle_error!(self, err, route.hops.first().unwrap().pubkey) {
1294                         Ok(_) => unreachable!(),
1295                         Err(e) => { Err(APIError::ChannelUnavailable { err: e.err }) }
1296                 }
1297         }
1298
1299         /// Call this upon creation of a funding transaction for the given channel.
1300         ///
1301         /// Note that ALL inputs in the transaction pointed to by funding_txo MUST spend SegWit outputs
1302         /// or your counterparty can steal your funds!
1303         ///
1304         /// Panics if a funding transaction has already been provided for this channel.
1305         ///
1306         /// May panic if the funding_txo is duplicative with some other channel (note that this should
1307         /// be trivially prevented by using unique funding transaction keys per-channel).
1308         pub fn funding_transaction_generated(&self, temporary_channel_id: &[u8; 32], funding_txo: OutPoint) {
1309                 let _ = self.total_consistency_lock.read().unwrap();
1310
1311                 let (mut chan, msg, chan_monitor) = {
1312                         let (res, chan) = match self.channel_state.lock().unwrap().by_id.remove(temporary_channel_id) {
1313                                 Some(mut chan) => {
1314                                         (chan.get_outbound_funding_created(funding_txo)
1315                                                 .map_err(|e| if let ChannelError::Close(msg) = e {
1316                                                         MsgHandleErrInternal::from_finish_shutdown(msg, chan.channel_id(), chan.force_shutdown(true), None)
1317                                                 } else { unreachable!(); })
1318                                         , chan)
1319                                 },
1320                                 None => return
1321                         };
1322                         match handle_error!(self, res, chan.get_their_node_id()) {
1323                                 Ok(funding_msg) => {
1324                                         (chan, funding_msg.0, funding_msg.1)
1325                                 },
1326                                 Err(_) => { return; }
1327                         }
1328                 };
1329                 // Because we have exclusive ownership of the channel here we can release the channel_state
1330                 // lock before add_monitor
1331                 if let Err(e) = self.monitor.add_monitor(chan_monitor.get_funding_txo().unwrap(), chan_monitor) {
1332                         match e {
1333                                 ChannelMonitorUpdateErr::PermanentFailure => {
1334                                         match handle_error!(self, Err(MsgHandleErrInternal::from_finish_shutdown("ChannelMonitor storage failure", *temporary_channel_id, chan.force_shutdown(true), None)), chan.get_their_node_id()) {
1335                                                 Err(_) => { return; },
1336                                                 Ok(()) => unreachable!(),
1337                                         }
1338                                 },
1339                                 ChannelMonitorUpdateErr::TemporaryFailure => {
1340                                         // Its completely fine to continue with a FundingCreated until the monitor
1341                                         // update is persisted, as long as we don't generate the FundingBroadcastSafe
1342                                         // until the monitor has been safely persisted (as funding broadcast is not,
1343                                         // in fact, safe).
1344                                         chan.monitor_update_failed(false, false, Vec::new(), Vec::new());
1345                                 },
1346                         }
1347                 }
1348
1349                 let mut channel_state = self.channel_state.lock().unwrap();
1350                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendFundingCreated {
1351                         node_id: chan.get_their_node_id(),
1352                         msg: msg,
1353                 });
1354                 match channel_state.by_id.entry(chan.channel_id()) {
1355                         hash_map::Entry::Occupied(_) => {
1356                                 panic!("Generated duplicate funding txid?");
1357                         },
1358                         hash_map::Entry::Vacant(e) => {
1359                                 e.insert(chan);
1360                         }
1361                 }
1362         }
1363
1364         fn get_announcement_sigs(&self, chan: &Channel<ChanSigner>) -> Option<msgs::AnnouncementSignatures> {
1365                 if !chan.should_announce() {
1366                         log_trace!(self, "Can't send announcement_signatures for private channel {}", log_bytes!(chan.channel_id()));
1367                         return None
1368                 }
1369
1370                 let (announcement, our_bitcoin_sig) = match chan.get_channel_announcement(self.get_our_node_id(), self.genesis_hash.clone()) {
1371                         Ok(res) => res,
1372                         Err(_) => return None, // Only in case of state precondition violations eg channel is closing
1373                 };
1374                 let msghash = hash_to_message!(&Sha256dHash::hash(&announcement.encode()[..])[..]);
1375                 let our_node_sig = self.secp_ctx.sign(&msghash, &self.our_network_key);
1376
1377                 Some(msgs::AnnouncementSignatures {
1378                         channel_id: chan.channel_id(),
1379                         short_channel_id: chan.get_short_channel_id().unwrap(),
1380                         node_signature: our_node_sig,
1381                         bitcoin_signature: our_bitcoin_sig,
1382                 })
1383         }
1384
1385         #[allow(dead_code)]
1386         // Messages of up to 64KB should never end up more than half full with addresses, as that would
1387         // be absurd. We ensure this by checking that at least 500 (our stated public contract on when
1388         // broadcast_node_announcement panics) of the maximum-length addresses would fit in a 64KB
1389         // message...
1390         const HALF_MESSAGE_IS_ADDRS: u32 = ::std::u16::MAX as u32 / (msgs::NetAddress::MAX_LEN as u32 + 1) / 2;
1391         #[deny(const_err)]
1392         #[allow(dead_code)]
1393         // ...by failing to compile if the number of addresses that would be half of a message is
1394         // smaller than 500:
1395         const STATIC_ASSERT: u32 = Self::HALF_MESSAGE_IS_ADDRS - 500;
1396
1397         /// Generates a signed node_announcement from the given arguments and creates a
1398         /// BroadcastNodeAnnouncement event. Note that such messages will be ignored unless peers have
1399         /// seen a channel_announcement from us (ie unless we have public channels open).
1400         ///
1401         /// RGB is a node "color" and alias is a printable human-readable string to describe this node
1402         /// to humans. They carry no in-protocol meaning.
1403         ///
1404         /// addresses represent the set (possibly empty) of socket addresses on which this node accepts
1405         /// incoming connections. These will be broadcast to the network, publicly tying these
1406         /// addresses together. If you wish to preserve user privacy, addresses should likely contain
1407         /// only Tor Onion addresses.
1408         ///
1409         /// Panics if addresses is absurdly large (more than 500).
1410         pub fn broadcast_node_announcement(&self, rgb: [u8; 3], alias: [u8; 32], addresses: Vec<msgs::NetAddress>) {
1411                 let _ = self.total_consistency_lock.read().unwrap();
1412
1413                 if addresses.len() > 500 {
1414                         panic!("More than half the message size was taken up by public addresses!");
1415                 }
1416
1417                 let announcement = msgs::UnsignedNodeAnnouncement {
1418                         features: NodeFeatures::supported(),
1419                         timestamp: self.last_node_announcement_serial.fetch_add(1, Ordering::AcqRel) as u32,
1420                         node_id: self.get_our_node_id(),
1421                         rgb, alias, addresses,
1422                         excess_address_data: Vec::new(),
1423                         excess_data: Vec::new(),
1424                 };
1425                 let msghash = hash_to_message!(&Sha256dHash::hash(&announcement.encode()[..])[..]);
1426
1427                 let mut channel_state = self.channel_state.lock().unwrap();
1428                 channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastNodeAnnouncement {
1429                         msg: msgs::NodeAnnouncement {
1430                                 signature: self.secp_ctx.sign(&msghash, &self.our_network_key),
1431                                 contents: announcement
1432                         },
1433                 });
1434         }
1435
1436         /// Processes HTLCs which are pending waiting on random forward delay.
1437         ///
1438         /// Should only really ever be called in response to a PendingHTLCsForwardable event.
1439         /// Will likely generate further events.
1440         pub fn process_pending_htlc_forwards(&self) {
1441                 let _ = self.total_consistency_lock.read().unwrap();
1442
1443                 let mut new_events = Vec::new();
1444                 let mut failed_forwards = Vec::new();
1445                 let mut handle_errors = Vec::new();
1446                 {
1447                         let mut channel_state_lock = self.channel_state.lock().unwrap();
1448                         let channel_state = &mut *channel_state_lock;
1449
1450                         for (short_chan_id, mut pending_forwards) in channel_state.forward_htlcs.drain() {
1451                                 if short_chan_id != 0 {
1452                                         let forward_chan_id = match channel_state.short_to_id.get(&short_chan_id) {
1453                                                 Some(chan_id) => chan_id.clone(),
1454                                                 None => {
1455                                                         failed_forwards.reserve(pending_forwards.len());
1456                                                         for forward_info in pending_forwards.drain(..) {
1457                                                                 match forward_info {
1458                                                                         HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info } => {
1459                                                                                 let htlc_source = HTLCSource::PreviousHopData(HTLCPreviousHopData {
1460                                                                                         short_channel_id: prev_short_channel_id,
1461                                                                                         htlc_id: prev_htlc_id,
1462                                                                                         incoming_packet_shared_secret: forward_info.incoming_shared_secret,
1463                                                                                 });
1464                                                                                 failed_forwards.push((htlc_source, forward_info.payment_hash, 0x4000 | 10, None));
1465                                                                         },
1466                                                                         HTLCForwardInfo::FailHTLC { .. } => {
1467                                                                                 // Channel went away before we could fail it. This implies
1468                                                                                 // the channel is now on chain and our counterparty is
1469                                                                                 // trying to broadcast the HTLC-Timeout, but that's their
1470                                                                                 // problem, not ours.
1471                                                                         }
1472                                                                 }
1473                                                         }
1474                                                         continue;
1475                                                 }
1476                                         };
1477                                         if let hash_map::Entry::Occupied(mut chan) = channel_state.by_id.entry(forward_chan_id) {
1478                                                 let mut add_htlc_msgs = Vec::new();
1479                                                 let mut fail_htlc_msgs = Vec::new();
1480                                                 for forward_info in pending_forwards.drain(..) {
1481                                                         match forward_info {
1482                                                                 HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info: PendingHTLCInfo {
1483                                                                                 routing: PendingHTLCRouting::Forward {
1484                                                                                         onion_packet, ..
1485                                                                                 }, incoming_shared_secret, payment_hash, amt_to_forward, outgoing_cltv_value }, } => {
1486                                                                         log_trace!(self, "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);
1487                                                                         let htlc_source = HTLCSource::PreviousHopData(HTLCPreviousHopData {
1488                                                                                 short_channel_id: prev_short_channel_id,
1489                                                                                 htlc_id: prev_htlc_id,
1490                                                                                 incoming_packet_shared_secret: incoming_shared_secret,
1491                                                                         });
1492                                                                         match chan.get_mut().send_htlc(amt_to_forward, payment_hash, outgoing_cltv_value, htlc_source.clone(), onion_packet) {
1493                                                                                 Err(e) => {
1494                                                                                         if let ChannelError::Ignore(msg) = e {
1495                                                                                                 log_trace!(self, "Failed to forward HTLC with payment_hash {}: {}", log_bytes!(payment_hash.0), msg);
1496                                                                                         } else {
1497                                                                                                 panic!("Stated return value requirements in send_htlc() were not met");
1498                                                                                         }
1499                                                                                         let chan_update = self.get_channel_update(chan.get()).unwrap();
1500                                                                                         failed_forwards.push((htlc_source, payment_hash, 0x1000 | 7, Some(chan_update)));
1501                                                                                         continue;
1502                                                                                 },
1503                                                                                 Ok(update_add) => {
1504                                                                                         match update_add {
1505                                                                                                 Some(msg) => { add_htlc_msgs.push(msg); },
1506                                                                                                 None => {
1507                                                                                                         // Nothing to do here...we're waiting on a remote
1508                                                                                                         // revoke_and_ack before we can add anymore HTLCs. The Channel
1509                                                                                                         // will automatically handle building the update_add_htlc and
1510                                                                                                         // commitment_signed messages when we can.
1511                                                                                                         // TODO: Do some kind of timer to set the channel as !is_live()
1512                                                                                                         // as we don't really want others relying on us relaying through
1513                                                                                                         // this channel currently :/.
1514                                                                                                 }
1515                                                                                         }
1516                                                                                 }
1517                                                                         }
1518                                                                 },
1519                                                                 HTLCForwardInfo::AddHTLC { .. } => {
1520                                                                         panic!("short_channel_id != 0 should imply any pending_forward entries are of type Forward");
1521                                                                 },
1522                                                                 HTLCForwardInfo::FailHTLC { htlc_id, err_packet } => {
1523                                                                         log_trace!(self, "Failing HTLC back to channel with short id {} after delay", short_chan_id);
1524                                                                         match chan.get_mut().get_update_fail_htlc(htlc_id, err_packet) {
1525                                                                                 Err(e) => {
1526                                                                                         if let ChannelError::Ignore(msg) = e {
1527                                                                                                 log_trace!(self, "Failed to fail backwards to short_id {}: {}", short_chan_id, msg);
1528                                                                                         } else {
1529                                                                                                 panic!("Stated return value requirements in get_update_fail_htlc() were not met");
1530                                                                                         }
1531                                                                                         // fail-backs are best-effort, we probably already have one
1532                                                                                         // pending, and if not that's OK, if not, the channel is on
1533                                                                                         // the chain and sending the HTLC-Timeout is their problem.
1534                                                                                         continue;
1535                                                                                 },
1536                                                                                 Ok(Some(msg)) => { fail_htlc_msgs.push(msg); },
1537                                                                                 Ok(None) => {
1538                                                                                         // Nothing to do here...we're waiting on a remote
1539                                                                                         // revoke_and_ack before we can update the commitment
1540                                                                                         // transaction. The Channel will automatically handle
1541                                                                                         // building the update_fail_htlc and commitment_signed
1542                                                                                         // messages when we can.
1543                                                                                         // We don't need any kind of timer here as they should fail
1544                                                                                         // the channel onto the chain if they can't get our
1545                                                                                         // update_fail_htlc in time, it's not our problem.
1546                                                                                 }
1547                                                                         }
1548                                                                 },
1549                                                         }
1550                                                 }
1551
1552                                                 if !add_htlc_msgs.is_empty() || !fail_htlc_msgs.is_empty() {
1553                                                         let (commitment_msg, monitor_update) = match chan.get_mut().send_commitment() {
1554                                                                 Ok(res) => res,
1555                                                                 Err(e) => {
1556                                                                         // We surely failed send_commitment due to bad keys, in that case
1557                                                                         // close channel and then send error message to peer.
1558                                                                         let their_node_id = chan.get().get_their_node_id();
1559                                                                         let err: Result<(), _>  = match e {
1560                                                                                 ChannelError::Ignore(_) => {
1561                                                                                         panic!("Stated return value requirements in send_commitment() were not met");
1562                                                                                 },
1563                                                                                 ChannelError::Close(msg) => {
1564                                                                                         log_trace!(self, "Closing channel {} due to Close-required error: {}", log_bytes!(chan.key()[..]), msg);
1565                                                                                         let (channel_id, mut channel) = chan.remove_entry();
1566                                                                                         if let Some(short_id) = channel.get_short_channel_id() {
1567                                                                                                 channel_state.short_to_id.remove(&short_id);
1568                                                                                         }
1569                                                                                         Err(MsgHandleErrInternal::from_finish_shutdown(msg, channel_id, channel.force_shutdown(true), self.get_channel_update(&channel).ok()))
1570                                                                                 },
1571                                                                                 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"); }
1572                                                                         };
1573                                                                         handle_errors.push((their_node_id, err));
1574                                                                         continue;
1575                                                                 }
1576                                                         };
1577                                                         if let Err(e) = self.monitor.update_monitor(chan.get().get_funding_txo().unwrap(), monitor_update) {
1578                                                                 handle_errors.push((chan.get().get_their_node_id(), handle_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::CommitmentFirst, false, true)));
1579                                                                 continue;
1580                                                         }
1581                                                         channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
1582                                                                 node_id: chan.get().get_their_node_id(),
1583                                                                 updates: msgs::CommitmentUpdate {
1584                                                                         update_add_htlcs: add_htlc_msgs,
1585                                                                         update_fulfill_htlcs: Vec::new(),
1586                                                                         update_fail_htlcs: fail_htlc_msgs,
1587                                                                         update_fail_malformed_htlcs: Vec::new(),
1588                                                                         update_fee: None,
1589                                                                         commitment_signed: commitment_msg,
1590                                                                 },
1591                                                         });
1592                                                 }
1593                                         } else {
1594                                                 unreachable!();
1595                                         }
1596                                 } else {
1597                                         for forward_info in pending_forwards.drain(..) {
1598                                                 match forward_info {
1599                                                         HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info: PendingHTLCInfo {
1600                                                                         routing: PendingHTLCRouting::Receive { payment_data },
1601                                                                         incoming_shared_secret, payment_hash, amt_to_forward, .. }, } => {
1602                                                                 let prev_hop = HTLCPreviousHopData {
1603                                                                         short_channel_id: prev_short_channel_id,
1604                                                                         htlc_id: prev_htlc_id,
1605                                                                         incoming_packet_shared_secret: incoming_shared_secret,
1606                                                                 };
1607                                                                 channel_state.claimable_htlcs.entry(payment_hash).or_insert(Vec::new()).push(ClaimableHTLC {
1608                                                                         prev_hop,
1609                                                                         value: amt_to_forward,
1610                                                                         payment_data,
1611                                                                 });
1612                                                                 new_events.push(events::Event::PaymentReceived {
1613                                                                         payment_hash: payment_hash,
1614                                                                         amt: amt_to_forward,
1615                                                                 });
1616                                                         },
1617                                                         HTLCForwardInfo::AddHTLC { .. } => {
1618                                                                 panic!("short_channel_id == 0 should imply any pending_forward entries are of type Receive");
1619                                                         },
1620                                                         HTLCForwardInfo::FailHTLC { .. } => {
1621                                                                 panic!("Got pending fail of our own HTLC");
1622                                                         }
1623                                                 }
1624                                         }
1625                                 }
1626                         }
1627                 }
1628
1629                 for (htlc_source, payment_hash, failure_code, update) in failed_forwards.drain(..) {
1630                         match update {
1631                                 None => self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), htlc_source, &payment_hash, HTLCFailReason::Reason { failure_code, data: Vec::new() }),
1632                                 Some(chan_update) => self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), htlc_source, &payment_hash, HTLCFailReason::Reason { failure_code, data: chan_update.encode_with_len() }),
1633                         };
1634                 }
1635
1636                 for (their_node_id, err) in handle_errors.drain(..) {
1637                         let _ = handle_error!(self, err, their_node_id);
1638                 }
1639
1640                 if new_events.is_empty() { return }
1641                 let mut events = self.pending_events.lock().unwrap();
1642                 events.append(&mut new_events);
1643         }
1644
1645         /// If a peer is disconnected we mark any channels with that peer as 'disabled'.
1646         /// After some time, if channels are still disabled we need to broadcast a ChannelUpdate
1647         /// to inform the network about the uselessness of these channels.
1648         ///
1649         /// This method handles all the details, and must be called roughly once per minute.
1650         pub fn timer_chan_freshness_every_min(&self) {
1651                 let _ = self.total_consistency_lock.read().unwrap();
1652                 let mut channel_state_lock = self.channel_state.lock().unwrap();
1653                 let channel_state = &mut *channel_state_lock;
1654                 for (_, chan) in channel_state.by_id.iter_mut() {
1655                         if chan.is_disabled_staged() && !chan.is_live() {
1656                                 if let Ok(update) = self.get_channel_update(&chan) {
1657                                         channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
1658                                                 msg: update
1659                                         });
1660                                 }
1661                                 chan.to_fresh();
1662                         } else if chan.is_disabled_staged() && chan.is_live() {
1663                                 chan.to_fresh();
1664                         } else if chan.is_disabled_marked() {
1665                                 chan.to_disabled_staged();
1666                         }
1667                 }
1668         }
1669
1670         /// Indicates that the preimage for payment_hash is unknown or the received amount is incorrect
1671         /// after a PaymentReceived event, failing the HTLC back to its origin and freeing resources
1672         /// along the path (including in our own channel on which we received it).
1673         /// Returns false if no payment was found to fail backwards, true if the process of failing the
1674         /// HTLC backwards has been started.
1675         pub fn fail_htlc_backwards(&self, payment_hash: &PaymentHash) -> bool {
1676                 let _ = self.total_consistency_lock.read().unwrap();
1677
1678                 let mut channel_state = Some(self.channel_state.lock().unwrap());
1679                 let removed_source = channel_state.as_mut().unwrap().claimable_htlcs.remove(payment_hash);
1680                 if let Some(mut sources) = removed_source {
1681                         for htlc in sources.drain(..) {
1682                                 if channel_state.is_none() { channel_state = Some(self.channel_state.lock().unwrap()); }
1683                                 self.fail_htlc_backwards_internal(channel_state.take().unwrap(),
1684                                                 HTLCSource::PreviousHopData(htlc.prev_hop), payment_hash,
1685                                                 HTLCFailReason::Reason { failure_code: 0x4000 | 15, data: byte_utils::be64_to_array(htlc.value).to_vec() });
1686                         }
1687                         true
1688                 } else { false }
1689         }
1690
1691         /// Fails an HTLC backwards to the sender of it to us.
1692         /// Note that while we take a channel_state lock as input, we do *not* assume consistency here.
1693         /// There are several callsites that do stupid things like loop over a list of payment_hashes
1694         /// to fail and take the channel_state lock for each iteration (as we take ownership and may
1695         /// drop it). In other words, no assumptions are made that entries in claimable_htlcs point to
1696         /// still-available channels.
1697         fn fail_htlc_backwards_internal(&self, mut channel_state_lock: MutexGuard<ChannelHolder<ChanSigner>>, source: HTLCSource, payment_hash: &PaymentHash, onion_error: HTLCFailReason) {
1698                 //TODO: There is a timing attack here where if a node fails an HTLC back to us they can
1699                 //identify whether we sent it or not based on the (I presume) very different runtime
1700                 //between the branches here. We should make this async and move it into the forward HTLCs
1701                 //timer handling.
1702                 match source {
1703                         HTLCSource::OutboundRoute { ref route, .. } => {
1704                                 log_trace!(self, "Failing outbound payment HTLC with payment_hash {}", log_bytes!(payment_hash.0));
1705                                 mem::drop(channel_state_lock);
1706                                 match &onion_error {
1707                                         &HTLCFailReason::LightningError { ref err } => {
1708 #[cfg(test)]
1709                                                 let (channel_update, payment_retryable, onion_error_code) = onion_utils::process_onion_failure(&self.secp_ctx, &self.logger, &source, err.data.clone());
1710 #[cfg(not(test))]
1711                                                 let (channel_update, payment_retryable, _) = onion_utils::process_onion_failure(&self.secp_ctx, &self.logger, &source, err.data.clone());
1712                                                 // TODO: If we decided to blame ourselves (or one of our channels) in
1713                                                 // process_onion_failure we should close that channel as it implies our
1714                                                 // next-hop is needlessly blaming us!
1715                                                 if let Some(update) = channel_update {
1716                                                         self.channel_state.lock().unwrap().pending_msg_events.push(
1717                                                                 events::MessageSendEvent::PaymentFailureNetworkUpdate {
1718                                                                         update,
1719                                                                 }
1720                                                         );
1721                                                 }
1722                                                 self.pending_events.lock().unwrap().push(
1723                                                         events::Event::PaymentFailed {
1724                                                                 payment_hash: payment_hash.clone(),
1725                                                                 rejected_by_dest: !payment_retryable,
1726 #[cfg(test)]
1727                                                                 error_code: onion_error_code
1728                                                         }
1729                                                 );
1730                                         },
1731                                         &HTLCFailReason::Reason {
1732 #[cfg(test)]
1733                                                         ref failure_code,
1734                                                         .. } => {
1735                                                 // we get a fail_malformed_htlc from the first hop
1736                                                 // TODO: We'd like to generate a PaymentFailureNetworkUpdate for temporary
1737                                                 // failures here, but that would be insufficient as Router::get_route
1738                                                 // generally ignores its view of our own channels as we provide them via
1739                                                 // ChannelDetails.
1740                                                 // TODO: For non-temporary failures, we really should be closing the
1741                                                 // channel here as we apparently can't relay through them anyway.
1742                                                 self.pending_events.lock().unwrap().push(
1743                                                         events::Event::PaymentFailed {
1744                                                                 payment_hash: payment_hash.clone(),
1745                                                                 rejected_by_dest: route.hops.len() == 1,
1746 #[cfg(test)]
1747                                                                 error_code: Some(*failure_code),
1748                                                         }
1749                                                 );
1750                                         }
1751                                 }
1752                         },
1753                         HTLCSource::PreviousHopData(HTLCPreviousHopData { short_channel_id, htlc_id, incoming_packet_shared_secret }) => {
1754                                 let err_packet = match onion_error {
1755                                         HTLCFailReason::Reason { failure_code, data } => {
1756                                                 log_trace!(self, "Failing HTLC with payment_hash {} backwards from us with code {}", log_bytes!(payment_hash.0), failure_code);
1757                                                 let packet = onion_utils::build_failure_packet(&incoming_packet_shared_secret, failure_code, &data[..]).encode();
1758                                                 onion_utils::encrypt_failure_packet(&incoming_packet_shared_secret, &packet)
1759                                         },
1760                                         HTLCFailReason::LightningError { err } => {
1761                                                 log_trace!(self, "Failing HTLC with payment_hash {} backwards with pre-built LightningError", log_bytes!(payment_hash.0));
1762                                                 onion_utils::encrypt_failure_packet(&incoming_packet_shared_secret, &err.data)
1763                                         }
1764                                 };
1765
1766                                 let mut forward_event = None;
1767                                 if channel_state_lock.forward_htlcs.is_empty() {
1768                                         forward_event = Some(Duration::from_millis(MIN_HTLC_RELAY_HOLDING_CELL_MILLIS));
1769                                 }
1770                                 match channel_state_lock.forward_htlcs.entry(short_channel_id) {
1771                                         hash_map::Entry::Occupied(mut entry) => {
1772                                                 entry.get_mut().push(HTLCForwardInfo::FailHTLC { htlc_id, err_packet });
1773                                         },
1774                                         hash_map::Entry::Vacant(entry) => {
1775                                                 entry.insert(vec!(HTLCForwardInfo::FailHTLC { htlc_id, err_packet }));
1776                                         }
1777                                 }
1778                                 mem::drop(channel_state_lock);
1779                                 if let Some(time) = forward_event {
1780                                         let mut pending_events = self.pending_events.lock().unwrap();
1781                                         pending_events.push(events::Event::PendingHTLCsForwardable {
1782                                                 time_forwardable: time
1783                                         });
1784                                 }
1785                         },
1786                 }
1787         }
1788
1789         /// Provides a payment preimage in response to a PaymentReceived event, returning true and
1790         /// generating message events for the net layer to claim the payment, if possible. Thus, you
1791         /// should probably kick the net layer to go send messages if this returns true!
1792         ///
1793         /// You must specify the expected amounts for this HTLC, and we will only claim HTLCs
1794         /// available within a few percent of the expected amount. This is critical for several
1795         /// reasons : a) it avoids providing senders with `proof-of-payment` (in the form of the
1796         /// payment_preimage without having provided the full value and b) it avoids certain
1797         /// privacy-breaking recipient-probing attacks which may reveal payment activity to
1798         /// motivated attackers.
1799         ///
1800         /// May panic if called except in response to a PaymentReceived event.
1801         pub fn claim_funds(&self, payment_preimage: PaymentPreimage, expected_amount: u64) -> bool {
1802                 let payment_hash = PaymentHash(Sha256::hash(&payment_preimage.0).into_inner());
1803
1804                 let _ = self.total_consistency_lock.read().unwrap();
1805
1806                 let mut channel_state = Some(self.channel_state.lock().unwrap());
1807                 let removed_source = channel_state.as_mut().unwrap().claimable_htlcs.remove(&payment_hash);
1808                 if let Some(mut sources) = removed_source {
1809                         for htlc in sources.drain(..) {
1810                                 if channel_state.is_none() { channel_state = Some(self.channel_state.lock().unwrap()); }
1811                                 if htlc.value < expected_amount || htlc.value > expected_amount * 2 {
1812                                         let mut htlc_msat_data = byte_utils::be64_to_array(htlc.value).to_vec();
1813                                         let mut height_data = byte_utils::be32_to_array(self.latest_block_height.load(Ordering::Acquire) as u32).to_vec();
1814                                         htlc_msat_data.append(&mut height_data);
1815                                         self.fail_htlc_backwards_internal(channel_state.take().unwrap(),
1816                                                                          HTLCSource::PreviousHopData(htlc.prev_hop), &payment_hash,
1817                                                                          HTLCFailReason::Reason { failure_code: 0x4000|15, data: htlc_msat_data });
1818                                 } else {
1819                                         self.claim_funds_internal(channel_state.take().unwrap(), HTLCSource::PreviousHopData(htlc.prev_hop), payment_preimage);
1820                                 }
1821                         }
1822                         true
1823                 } else { false }
1824         }
1825         fn claim_funds_internal(&self, mut channel_state_lock: MutexGuard<ChannelHolder<ChanSigner>>, source: HTLCSource, payment_preimage: PaymentPreimage) {
1826                 let (their_node_id, err) = loop {
1827                         match source {
1828                                 HTLCSource::OutboundRoute { .. } => {
1829                                         mem::drop(channel_state_lock);
1830                                         let mut pending_events = self.pending_events.lock().unwrap();
1831                                         pending_events.push(events::Event::PaymentSent {
1832                                                 payment_preimage
1833                                         });
1834                                 },
1835                                 HTLCSource::PreviousHopData(HTLCPreviousHopData { short_channel_id, htlc_id, .. }) => {
1836                                         //TODO: Delay the claimed_funds relaying just like we do outbound relay!
1837                                         let channel_state = &mut *channel_state_lock;
1838
1839                                         let chan_id = match channel_state.short_to_id.get(&short_channel_id) {
1840                                                 Some(chan_id) => chan_id.clone(),
1841                                                 None => {
1842                                                         // TODO: There is probably a channel manager somewhere that needs to
1843                                                         // learn the preimage as the channel already hit the chain and that's
1844                                                         // why it's missing.
1845                                                         return
1846                                                 }
1847                                         };
1848
1849                                         if let hash_map::Entry::Occupied(mut chan) = channel_state.by_id.entry(chan_id) {
1850                                                 let was_frozen_for_monitor = chan.get().is_awaiting_monitor_update();
1851                                                 match chan.get_mut().get_update_fulfill_htlc_and_commit(htlc_id, payment_preimage) {
1852                                                         Ok((msgs, monitor_option)) => {
1853                                                                 if let Some(monitor_update) = monitor_option {
1854                                                                         if let Err(e) = self.monitor.update_monitor(chan.get().get_funding_txo().unwrap(), monitor_update) {
1855                                                                                 if was_frozen_for_monitor {
1856                                                                                         assert!(msgs.is_none());
1857                                                                                 } else {
1858                                                                                         break (chan.get().get_their_node_id(), handle_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::CommitmentFirst, false, msgs.is_some()));
1859                                                                                 }
1860                                                                         }
1861                                                                 }
1862                                                                 if let Some((msg, commitment_signed)) = msgs {
1863                                                                         channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
1864                                                                                 node_id: chan.get().get_their_node_id(),
1865                                                                                 updates: msgs::CommitmentUpdate {
1866                                                                                         update_add_htlcs: Vec::new(),
1867                                                                                         update_fulfill_htlcs: vec![msg],
1868                                                                                         update_fail_htlcs: Vec::new(),
1869                                                                                         update_fail_malformed_htlcs: Vec::new(),
1870                                                                                         update_fee: None,
1871                                                                                         commitment_signed,
1872                                                                                 }
1873                                                                         });
1874                                                                 }
1875                                                         },
1876                                                         Err(_e) => {
1877                                                                 // TODO: There is probably a channel manager somewhere that needs to
1878                                                                 // learn the preimage as the channel may be about to hit the chain.
1879                                                                 //TODO: Do something with e?
1880                                                                 return
1881                                                         },
1882                                                 }
1883                                         } else { unreachable!(); }
1884                                 },
1885                         }
1886                         return;
1887                 };
1888
1889                 mem::drop(channel_state_lock);
1890                 let _ = handle_error!(self, err, their_node_id);
1891         }
1892
1893         /// Gets the node_id held by this ChannelManager
1894         pub fn get_our_node_id(&self) -> PublicKey {
1895                 PublicKey::from_secret_key(&self.secp_ctx, &self.our_network_key)
1896         }
1897
1898         /// Restores a single, given channel to normal operation after a
1899         /// ChannelMonitorUpdateErr::TemporaryFailure was returned from a channel monitor update
1900         /// operation.
1901         ///
1902         /// All ChannelMonitor updates up to and including highest_applied_update_id must have been
1903         /// fully committed in every copy of the given channels' ChannelMonitors.
1904         ///
1905         /// Note that there is no effect to calling with a highest_applied_update_id other than the
1906         /// current latest ChannelMonitorUpdate and one call to this function after multiple
1907         /// ChannelMonitorUpdateErr::TemporaryFailures is fine. The highest_applied_update_id field
1908         /// exists largely only to prevent races between this and concurrent update_monitor calls.
1909         ///
1910         /// Thus, the anticipated use is, at a high level:
1911         ///  1) You register a ManyChannelMonitor with this ChannelManager,
1912         ///  2) it stores each update to disk, and begins updating any remote (eg watchtower) copies of
1913         ///     said ChannelMonitors as it can, returning ChannelMonitorUpdateErr::TemporaryFailures
1914         ///     any time it cannot do so instantly,
1915         ///  3) update(s) are applied to each remote copy of a ChannelMonitor,
1916         ///  4) once all remote copies are updated, you call this function with the update_id that
1917         ///     completed, and once it is the latest the Channel will be re-enabled.
1918         pub fn channel_monitor_updated(&self, funding_txo: &OutPoint, highest_applied_update_id: u64) {
1919                 let _ = self.total_consistency_lock.read().unwrap();
1920
1921                 let mut close_results = Vec::new();
1922                 let mut htlc_forwards = Vec::new();
1923                 let mut htlc_failures = Vec::new();
1924                 let mut pending_events = Vec::new();
1925
1926                 {
1927                         let mut channel_lock = self.channel_state.lock().unwrap();
1928                         let channel_state = &mut *channel_lock;
1929                         let short_to_id = &mut channel_state.short_to_id;
1930                         let pending_msg_events = &mut channel_state.pending_msg_events;
1931                         let channel = match channel_state.by_id.get_mut(&funding_txo.to_channel_id()) {
1932                                 Some(chan) => chan,
1933                                 None => return,
1934                         };
1935                         if !channel.is_awaiting_monitor_update() || channel.get_latest_monitor_update_id() != highest_applied_update_id {
1936                                 return;
1937                         }
1938
1939                         let (raa, commitment_update, order, pending_forwards, mut pending_failures, needs_broadcast_safe, funding_locked) = channel.monitor_updating_restored();
1940                         if !pending_forwards.is_empty() {
1941                                 htlc_forwards.push((channel.get_short_channel_id().expect("We can't have pending forwards before funding confirmation"), pending_forwards));
1942                         }
1943                         htlc_failures.append(&mut pending_failures);
1944
1945                         macro_rules! handle_cs { () => {
1946                                 if let Some(update) = commitment_update {
1947                                         pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
1948                                                 node_id: channel.get_their_node_id(),
1949                                                 updates: update,
1950                                         });
1951                                 }
1952                         } }
1953                         macro_rules! handle_raa { () => {
1954                                 if let Some(revoke_and_ack) = raa {
1955                                         pending_msg_events.push(events::MessageSendEvent::SendRevokeAndACK {
1956                                                 node_id: channel.get_their_node_id(),
1957                                                 msg: revoke_and_ack,
1958                                         });
1959                                 }
1960                         } }
1961                         match order {
1962                                 RAACommitmentOrder::CommitmentFirst => {
1963                                         handle_cs!();
1964                                         handle_raa!();
1965                                 },
1966                                 RAACommitmentOrder::RevokeAndACKFirst => {
1967                                         handle_raa!();
1968                                         handle_cs!();
1969                                 },
1970                         }
1971                         if needs_broadcast_safe {
1972                                 pending_events.push(events::Event::FundingBroadcastSafe {
1973                                         funding_txo: channel.get_funding_txo().unwrap(),
1974                                         user_channel_id: channel.get_user_id(),
1975                                 });
1976                         }
1977                         if let Some(msg) = funding_locked {
1978                                 pending_msg_events.push(events::MessageSendEvent::SendFundingLocked {
1979                                         node_id: channel.get_their_node_id(),
1980                                         msg,
1981                                 });
1982                                 if let Some(announcement_sigs) = self.get_announcement_sigs(channel) {
1983                                         pending_msg_events.push(events::MessageSendEvent::SendAnnouncementSignatures {
1984                                                 node_id: channel.get_their_node_id(),
1985                                                 msg: announcement_sigs,
1986                                         });
1987                                 }
1988                                 short_to_id.insert(channel.get_short_channel_id().unwrap(), channel.channel_id());
1989                         }
1990                 }
1991
1992                 self.pending_events.lock().unwrap().append(&mut pending_events);
1993
1994                 for failure in htlc_failures.drain(..) {
1995                         self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), failure.0, &failure.1, failure.2);
1996                 }
1997                 self.forward_htlcs(&mut htlc_forwards[..]);
1998
1999                 for res in close_results.drain(..) {
2000                         self.finish_force_close_channel(res);
2001                 }
2002         }
2003
2004         fn internal_open_channel(&self, their_node_id: &PublicKey, their_features: InitFeatures, msg: &msgs::OpenChannel) -> Result<(), MsgHandleErrInternal> {
2005                 if msg.chain_hash != self.genesis_hash {
2006                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Unknown genesis block hash", msg.temporary_channel_id.clone()));
2007                 }
2008
2009                 let channel = Channel::new_from_req(&self.fee_estimator, &self.keys_manager, their_node_id.clone(), their_features, msg, 0, Arc::clone(&self.logger), &self.default_configuration)
2010                         .map_err(|e| MsgHandleErrInternal::from_chan_no_close(e, msg.temporary_channel_id))?;
2011                 let mut channel_state_lock = self.channel_state.lock().unwrap();
2012                 let channel_state = &mut *channel_state_lock;
2013                 match channel_state.by_id.entry(channel.channel_id()) {
2014                         hash_map::Entry::Occupied(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("temporary_channel_id collision!", msg.temporary_channel_id.clone())),
2015                         hash_map::Entry::Vacant(entry) => {
2016                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendAcceptChannel {
2017                                         node_id: their_node_id.clone(),
2018                                         msg: channel.get_accept_channel(),
2019                                 });
2020                                 entry.insert(channel);
2021                         }
2022                 }
2023                 Ok(())
2024         }
2025
2026         fn internal_accept_channel(&self, their_node_id: &PublicKey, their_features: InitFeatures, msg: &msgs::AcceptChannel) -> Result<(), MsgHandleErrInternal> {
2027                 let (value, output_script, user_id) = {
2028                         let mut channel_lock = self.channel_state.lock().unwrap();
2029                         let channel_state = &mut *channel_lock;
2030                         match channel_state.by_id.entry(msg.temporary_channel_id) {
2031                                 hash_map::Entry::Occupied(mut chan) => {
2032                                         if chan.get().get_their_node_id() != *their_node_id {
2033                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.temporary_channel_id));
2034                                         }
2035                                         try_chan_entry!(self, chan.get_mut().accept_channel(&msg, &self.default_configuration, their_features), channel_state, chan);
2036                                         (chan.get().get_value_satoshis(), chan.get().get_funding_redeemscript().to_v0_p2wsh(), chan.get().get_user_id())
2037                                 },
2038                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.temporary_channel_id))
2039                         }
2040                 };
2041                 let mut pending_events = self.pending_events.lock().unwrap();
2042                 pending_events.push(events::Event::FundingGenerationReady {
2043                         temporary_channel_id: msg.temporary_channel_id,
2044                         channel_value_satoshis: value,
2045                         output_script: output_script,
2046                         user_channel_id: user_id,
2047                 });
2048                 Ok(())
2049         }
2050
2051         fn internal_funding_created(&self, their_node_id: &PublicKey, msg: &msgs::FundingCreated) -> Result<(), MsgHandleErrInternal> {
2052                 let ((funding_msg, monitor_update), mut chan) = {
2053                         let mut channel_lock = self.channel_state.lock().unwrap();
2054                         let channel_state = &mut *channel_lock;
2055                         match channel_state.by_id.entry(msg.temporary_channel_id.clone()) {
2056                                 hash_map::Entry::Occupied(mut chan) => {
2057                                         if chan.get().get_their_node_id() != *their_node_id {
2058                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.temporary_channel_id));
2059                                         }
2060                                         (try_chan_entry!(self, chan.get_mut().funding_created(msg), channel_state, chan), chan.remove())
2061                                 },
2062                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.temporary_channel_id))
2063                         }
2064                 };
2065                 // Because we have exclusive ownership of the channel here we can release the channel_state
2066                 // lock before add_monitor
2067                 if let Err(e) = self.monitor.add_monitor(monitor_update.get_funding_txo().unwrap(), monitor_update) {
2068                         match e {
2069                                 ChannelMonitorUpdateErr::PermanentFailure => {
2070                                         // Note that we reply with the new channel_id in error messages if we gave up on the
2071                                         // channel, not the temporary_channel_id. This is compatible with ourselves, but the
2072                                         // spec is somewhat ambiguous here. Not a huge deal since we'll send error messages for
2073                                         // any messages referencing a previously-closed channel anyway.
2074                                         return Err(MsgHandleErrInternal::from_finish_shutdown("ChannelMonitor storage failure", funding_msg.channel_id, chan.force_shutdown(true), None));
2075                                 },
2076                                 ChannelMonitorUpdateErr::TemporaryFailure => {
2077                                         // There's no problem signing a counterparty's funding transaction if our monitor
2078                                         // hasn't persisted to disk yet - we can't lose money on a transaction that we haven't
2079                                         // accepted payment from yet. We do, however, need to wait to send our funding_locked
2080                                         // until we have persisted our monitor.
2081                                         chan.monitor_update_failed(false, false, Vec::new(), Vec::new());
2082                                 },
2083                         }
2084                 }
2085                 let mut channel_state_lock = self.channel_state.lock().unwrap();
2086                 let channel_state = &mut *channel_state_lock;
2087                 match channel_state.by_id.entry(funding_msg.channel_id) {
2088                         hash_map::Entry::Occupied(_) => {
2089                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Already had channel with the new channel_id", funding_msg.channel_id))
2090                         },
2091                         hash_map::Entry::Vacant(e) => {
2092                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendFundingSigned {
2093                                         node_id: their_node_id.clone(),
2094                                         msg: funding_msg,
2095                                 });
2096                                 e.insert(chan);
2097                         }
2098                 }
2099                 Ok(())
2100         }
2101
2102         fn internal_funding_signed(&self, their_node_id: &PublicKey, msg: &msgs::FundingSigned) -> Result<(), MsgHandleErrInternal> {
2103                 let (funding_txo, user_id) = {
2104                         let mut channel_lock = self.channel_state.lock().unwrap();
2105                         let channel_state = &mut *channel_lock;
2106                         match channel_state.by_id.entry(msg.channel_id) {
2107                                 hash_map::Entry::Occupied(mut chan) => {
2108                                         if chan.get().get_their_node_id() != *their_node_id {
2109                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2110                                         }
2111                                         let monitor_update = match chan.get_mut().funding_signed(&msg) {
2112                                                 Err((None, e)) => try_chan_entry!(self, Err(e), channel_state, chan),
2113                                                 Err((Some(monitor_update), e)) => {
2114                                                         assert!(chan.get().is_awaiting_monitor_update());
2115                                                         let _ = self.monitor.update_monitor(chan.get().get_funding_txo().unwrap(), monitor_update);
2116                                                         try_chan_entry!(self, Err(e), channel_state, chan);
2117                                                         unreachable!();
2118                                                 },
2119                                                 Ok(update) => update,
2120                                         };
2121                                         if let Err(e) = self.monitor.update_monitor(chan.get().get_funding_txo().unwrap(), monitor_update) {
2122                                                 return_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::RevokeAndACKFirst, false, false);
2123                                         }
2124                                         (chan.get().get_funding_txo().unwrap(), chan.get().get_user_id())
2125                                 },
2126                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2127                         }
2128                 };
2129                 let mut pending_events = self.pending_events.lock().unwrap();
2130                 pending_events.push(events::Event::FundingBroadcastSafe {
2131                         funding_txo: funding_txo,
2132                         user_channel_id: user_id,
2133                 });
2134                 Ok(())
2135         }
2136
2137         fn internal_funding_locked(&self, their_node_id: &PublicKey, msg: &msgs::FundingLocked) -> Result<(), MsgHandleErrInternal> {
2138                 let mut channel_state_lock = self.channel_state.lock().unwrap();
2139                 let channel_state = &mut *channel_state_lock;
2140                 match channel_state.by_id.entry(msg.channel_id) {
2141                         hash_map::Entry::Occupied(mut chan) => {
2142                                 if chan.get().get_their_node_id() != *their_node_id {
2143                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2144                                 }
2145                                 try_chan_entry!(self, chan.get_mut().funding_locked(&msg), channel_state, chan);
2146                                 if let Some(announcement_sigs) = self.get_announcement_sigs(chan.get()) {
2147                                         log_trace!(self, "Sending announcement_signatures for {} in response to funding_locked", log_bytes!(chan.get().channel_id()));
2148                                         // If we see locking block before receiving remote funding_locked, we broadcast our
2149                                         // announcement_sigs at remote funding_locked reception. If we receive remote
2150                                         // funding_locked before seeing locking block, we broadcast our announcement_sigs at locking
2151                                         // block connection. We should guanrantee to broadcast announcement_sigs to our peer whatever
2152                                         // the order of the events but our peer may not receive it due to disconnection. The specs
2153                                         // lacking an acknowledgement for announcement_sigs we may have to re-send them at peer
2154                                         // connection in the future if simultaneous misses by both peers due to network/hardware
2155                                         // failures is an issue. Note, to achieve its goal, only one of the announcement_sigs needs
2156                                         // to be received, from then sigs are going to be flood to the whole network.
2157                                         channel_state.pending_msg_events.push(events::MessageSendEvent::SendAnnouncementSignatures {
2158                                                 node_id: their_node_id.clone(),
2159                                                 msg: announcement_sigs,
2160                                         });
2161                                 }
2162                                 Ok(())
2163                         },
2164                         hash_map::Entry::Vacant(_) => Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2165                 }
2166         }
2167
2168         fn internal_shutdown(&self, their_node_id: &PublicKey, msg: &msgs::Shutdown) -> Result<(), MsgHandleErrInternal> {
2169                 let (mut dropped_htlcs, chan_option) = {
2170                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2171                         let channel_state = &mut *channel_state_lock;
2172
2173                         match channel_state.by_id.entry(msg.channel_id.clone()) {
2174                                 hash_map::Entry::Occupied(mut chan_entry) => {
2175                                         if chan_entry.get().get_their_node_id() != *their_node_id {
2176                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2177                                         }
2178                                         let (shutdown, closing_signed, dropped_htlcs) = try_chan_entry!(self, chan_entry.get_mut().shutdown(&self.fee_estimator, &msg), channel_state, chan_entry);
2179                                         if let Some(msg) = shutdown {
2180                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendShutdown {
2181                                                         node_id: their_node_id.clone(),
2182                                                         msg,
2183                                                 });
2184                                         }
2185                                         if let Some(msg) = closing_signed {
2186                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendClosingSigned {
2187                                                         node_id: their_node_id.clone(),
2188                                                         msg,
2189                                                 });
2190                                         }
2191                                         if chan_entry.get().is_shutdown() {
2192                                                 if let Some(short_id) = chan_entry.get().get_short_channel_id() {
2193                                                         channel_state.short_to_id.remove(&short_id);
2194                                                 }
2195                                                 (dropped_htlcs, Some(chan_entry.remove_entry().1))
2196                                         } else { (dropped_htlcs, None) }
2197                                 },
2198                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2199                         }
2200                 };
2201                 for htlc_source in dropped_htlcs.drain(..) {
2202                         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() });
2203                 }
2204                 if let Some(chan) = chan_option {
2205                         if let Ok(update) = self.get_channel_update(&chan) {
2206                                 let mut channel_state = self.channel_state.lock().unwrap();
2207                                 channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
2208                                         msg: update
2209                                 });
2210                         }
2211                 }
2212                 Ok(())
2213         }
2214
2215         fn internal_closing_signed(&self, their_node_id: &PublicKey, msg: &msgs::ClosingSigned) -> Result<(), MsgHandleErrInternal> {
2216                 let (tx, chan_option) = {
2217                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2218                         let channel_state = &mut *channel_state_lock;
2219                         match channel_state.by_id.entry(msg.channel_id.clone()) {
2220                                 hash_map::Entry::Occupied(mut chan_entry) => {
2221                                         if chan_entry.get().get_their_node_id() != *their_node_id {
2222                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2223                                         }
2224                                         let (closing_signed, tx) = try_chan_entry!(self, chan_entry.get_mut().closing_signed(&self.fee_estimator, &msg), channel_state, chan_entry);
2225                                         if let Some(msg) = closing_signed {
2226                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendClosingSigned {
2227                                                         node_id: their_node_id.clone(),
2228                                                         msg,
2229                                                 });
2230                                         }
2231                                         if tx.is_some() {
2232                                                 // We're done with this channel, we've got a signed closing transaction and
2233                                                 // will send the closing_signed back to the remote peer upon return. This
2234                                                 // also implies there are no pending HTLCs left on the channel, so we can
2235                                                 // fully delete it from tracking (the channel monitor is still around to
2236                                                 // watch for old state broadcasts)!
2237                                                 if let Some(short_id) = chan_entry.get().get_short_channel_id() {
2238                                                         channel_state.short_to_id.remove(&short_id);
2239                                                 }
2240                                                 (tx, Some(chan_entry.remove_entry().1))
2241                                         } else { (tx, None) }
2242                                 },
2243                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2244                         }
2245                 };
2246                 if let Some(broadcast_tx) = tx {
2247                         log_trace!(self, "Broadcast onchain {}", log_tx!(broadcast_tx));
2248                         self.tx_broadcaster.broadcast_transaction(&broadcast_tx);
2249                 }
2250                 if let Some(chan) = chan_option {
2251                         if let Ok(update) = self.get_channel_update(&chan) {
2252                                 let mut channel_state = self.channel_state.lock().unwrap();
2253                                 channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
2254                                         msg: update
2255                                 });
2256                         }
2257                 }
2258                 Ok(())
2259         }
2260
2261         fn internal_update_add_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateAddHTLC) -> Result<(), MsgHandleErrInternal> {
2262                 //TODO: BOLT 4 points out a specific attack where a peer may re-send an onion packet and
2263                 //determine the state of the payment based on our response/if we forward anything/the time
2264                 //we take to respond. We should take care to avoid allowing such an attack.
2265                 //
2266                 //TODO: There exists a further attack where a node may garble the onion data, forward it to
2267                 //us repeatedly garbled in different ways, and compare our error messages, which are
2268                 //encrypted with the same key. It's not immediately obvious how to usefully exploit that,
2269                 //but we should prevent it anyway.
2270
2271                 let (mut pending_forward_info, mut channel_state_lock) = self.decode_update_add_htlc_onion(msg);
2272                 let channel_state = &mut *channel_state_lock;
2273
2274                 match channel_state.by_id.entry(msg.channel_id) {
2275                         hash_map::Entry::Occupied(mut chan) => {
2276                                 if chan.get().get_their_node_id() != *their_node_id {
2277                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2278                                 }
2279                                 if !chan.get().is_usable() {
2280                                         // If the update_add is completely bogus, the call will Err and we will close,
2281                                         // but if we've sent a shutdown and they haven't acknowledged it yet, we just
2282                                         // want to reject the new HTLC and fail it backwards instead of forwarding.
2283                                         if let PendingHTLCStatus::Forward(PendingHTLCInfo { incoming_shared_secret, .. }) = pending_forward_info {
2284                                                 let chan_update = self.get_channel_update(chan.get());
2285                                                 pending_forward_info = PendingHTLCStatus::Fail(HTLCFailureMsg::Relay(msgs::UpdateFailHTLC {
2286                                                         channel_id: msg.channel_id,
2287                                                         htlc_id: msg.htlc_id,
2288                                                         reason: if let Ok(update) = chan_update {
2289                                                                 // TODO: Note that |20 is defined as "channel FROM the processing
2290                                                                 // node has been disabled" (emphasis mine), which seems to imply
2291                                                                 // that we can't return |20 for an inbound channel being disabled.
2292                                                                 // This probably needs a spec update but should definitely be
2293                                                                 // allowed.
2294                                                                 onion_utils::build_first_hop_failure_packet(&incoming_shared_secret, 0x1000|20, &{
2295                                                                         let mut res = Vec::with_capacity(8 + 128);
2296                                                                         res.extend_from_slice(&byte_utils::be16_to_array(update.contents.flags));
2297                                                                         res.extend_from_slice(&update.encode_with_len()[..]);
2298                                                                         res
2299                                                                 }[..])
2300                                                         } else {
2301                                                                 // This can only happen if the channel isn't in the fully-funded
2302                                                                 // state yet, implying our counterparty is trying to route payments
2303                                                                 // over the channel back to themselves (cause no one else should
2304                                                                 // know the short_id is a lightning channel yet). We should have no
2305                                                                 // problem just calling this unknown_next_peer
2306                                                                 onion_utils::build_first_hop_failure_packet(&incoming_shared_secret, 0x4000|10, &[])
2307                                                         },
2308                                                 }));
2309                                         }
2310                                 }
2311                                 try_chan_entry!(self, chan.get_mut().update_add_htlc(&msg, pending_forward_info), channel_state, chan);
2312                         },
2313                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2314                 }
2315                 Ok(())
2316         }
2317
2318         fn internal_update_fulfill_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFulfillHTLC) -> Result<(), MsgHandleErrInternal> {
2319                 let mut channel_lock = self.channel_state.lock().unwrap();
2320                 let htlc_source = {
2321                         let channel_state = &mut *channel_lock;
2322                         match channel_state.by_id.entry(msg.channel_id) {
2323                                 hash_map::Entry::Occupied(mut chan) => {
2324                                         if chan.get().get_their_node_id() != *their_node_id {
2325                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2326                                         }
2327                                         try_chan_entry!(self, chan.get_mut().update_fulfill_htlc(&msg), channel_state, chan)
2328                                 },
2329                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2330                         }
2331                 };
2332                 self.claim_funds_internal(channel_lock, htlc_source, msg.payment_preimage.clone());
2333                 Ok(())
2334         }
2335
2336         fn internal_update_fail_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFailHTLC) -> Result<(), MsgHandleErrInternal> {
2337                 let mut channel_lock = self.channel_state.lock().unwrap();
2338                 let channel_state = &mut *channel_lock;
2339                 match channel_state.by_id.entry(msg.channel_id) {
2340                         hash_map::Entry::Occupied(mut chan) => {
2341                                 if chan.get().get_their_node_id() != *their_node_id {
2342                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2343                                 }
2344                                 try_chan_entry!(self, chan.get_mut().update_fail_htlc(&msg, HTLCFailReason::LightningError { err: msg.reason.clone() }), channel_state, chan);
2345                         },
2346                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2347                 }
2348                 Ok(())
2349         }
2350
2351         fn internal_update_fail_malformed_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFailMalformedHTLC) -> Result<(), MsgHandleErrInternal> {
2352                 let mut channel_lock = self.channel_state.lock().unwrap();
2353                 let channel_state = &mut *channel_lock;
2354                 match channel_state.by_id.entry(msg.channel_id) {
2355                         hash_map::Entry::Occupied(mut chan) => {
2356                                 if chan.get().get_their_node_id() != *their_node_id {
2357                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2358                                 }
2359                                 if (msg.failure_code & 0x8000) == 0 {
2360                                         let chan_err: ChannelError = ChannelError::Close("Got update_fail_malformed_htlc with BADONION not set");
2361                                         try_chan_entry!(self, Err(chan_err), channel_state, chan);
2362                                 }
2363                                 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);
2364                                 Ok(())
2365                         },
2366                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2367                 }
2368         }
2369
2370         fn internal_commitment_signed(&self, their_node_id: &PublicKey, msg: &msgs::CommitmentSigned) -> Result<(), MsgHandleErrInternal> {
2371                 let mut channel_state_lock = self.channel_state.lock().unwrap();
2372                 let channel_state = &mut *channel_state_lock;
2373                 match channel_state.by_id.entry(msg.channel_id) {
2374                         hash_map::Entry::Occupied(mut chan) => {
2375                                 if chan.get().get_their_node_id() != *their_node_id {
2376                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2377                                 }
2378                                 let (revoke_and_ack, commitment_signed, closing_signed, monitor_update) =
2379                                                 match chan.get_mut().commitment_signed(&msg, &self.fee_estimator) {
2380                                         Err((None, e)) => try_chan_entry!(self, Err(e), channel_state, chan),
2381                                         Err((Some(update), e)) => {
2382                                                 assert!(chan.get().is_awaiting_monitor_update());
2383                                                 let _ = self.monitor.update_monitor(chan.get().get_funding_txo().unwrap(), update);
2384                                                 try_chan_entry!(self, Err(e), channel_state, chan);
2385                                                 unreachable!();
2386                                         },
2387                                         Ok(res) => res
2388                                 };
2389                                 if let Err(e) = self.monitor.update_monitor(chan.get().get_funding_txo().unwrap(), monitor_update) {
2390                                         return_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::RevokeAndACKFirst, true, commitment_signed.is_some());
2391                                         //TODO: Rebroadcast closing_signed if present on monitor update restoration
2392                                 }
2393                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendRevokeAndACK {
2394                                         node_id: their_node_id.clone(),
2395                                         msg: revoke_and_ack,
2396                                 });
2397                                 if let Some(msg) = commitment_signed {
2398                                         channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
2399                                                 node_id: their_node_id.clone(),
2400                                                 updates: msgs::CommitmentUpdate {
2401                                                         update_add_htlcs: Vec::new(),
2402                                                         update_fulfill_htlcs: Vec::new(),
2403                                                         update_fail_htlcs: Vec::new(),
2404                                                         update_fail_malformed_htlcs: Vec::new(),
2405                                                         update_fee: None,
2406                                                         commitment_signed: msg,
2407                                                 },
2408                                         });
2409                                 }
2410                                 if let Some(msg) = closing_signed {
2411                                         channel_state.pending_msg_events.push(events::MessageSendEvent::SendClosingSigned {
2412                                                 node_id: their_node_id.clone(),
2413                                                 msg,
2414                                         });
2415                                 }
2416                                 Ok(())
2417                         },
2418                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2419                 }
2420         }
2421
2422         #[inline]
2423         fn forward_htlcs(&self, per_source_pending_forwards: &mut [(u64, Vec<(PendingHTLCInfo, u64)>)]) {
2424                 for &mut (prev_short_channel_id, ref mut pending_forwards) in per_source_pending_forwards {
2425                         let mut forward_event = None;
2426                         if !pending_forwards.is_empty() {
2427                                 let mut channel_state = self.channel_state.lock().unwrap();
2428                                 if channel_state.forward_htlcs.is_empty() {
2429                                         forward_event = Some(Duration::from_millis(MIN_HTLC_RELAY_HOLDING_CELL_MILLIS))
2430                                 }
2431                                 for (forward_info, prev_htlc_id) in pending_forwards.drain(..) {
2432                                         match channel_state.forward_htlcs.entry(match forward_info.routing {
2433                                                         PendingHTLCRouting::Forward { short_channel_id, .. } => short_channel_id,
2434                                                         PendingHTLCRouting::Receive { .. } => 0,
2435                                         }) {
2436                                                 hash_map::Entry::Occupied(mut entry) => {
2437                                                         entry.get_mut().push(HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info });
2438                                                 },
2439                                                 hash_map::Entry::Vacant(entry) => {
2440                                                         entry.insert(vec!(HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info }));
2441                                                 }
2442                                         }
2443                                 }
2444                         }
2445                         match forward_event {
2446                                 Some(time) => {
2447                                         let mut pending_events = self.pending_events.lock().unwrap();
2448                                         pending_events.push(events::Event::PendingHTLCsForwardable {
2449                                                 time_forwardable: time
2450                                         });
2451                                 }
2452                                 None => {},
2453                         }
2454                 }
2455         }
2456
2457         fn internal_revoke_and_ack(&self, their_node_id: &PublicKey, msg: &msgs::RevokeAndACK) -> Result<(), MsgHandleErrInternal> {
2458                 let (pending_forwards, mut pending_failures, short_channel_id) = {
2459                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2460                         let channel_state = &mut *channel_state_lock;
2461                         match channel_state.by_id.entry(msg.channel_id) {
2462                                 hash_map::Entry::Occupied(mut chan) => {
2463                                         if chan.get().get_their_node_id() != *their_node_id {
2464                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2465                                         }
2466                                         let was_frozen_for_monitor = chan.get().is_awaiting_monitor_update();
2467                                         let (commitment_update, pending_forwards, pending_failures, closing_signed, monitor_update) =
2468                                                 try_chan_entry!(self, chan.get_mut().revoke_and_ack(&msg, &self.fee_estimator), channel_state, chan);
2469                                         if let Err(e) = self.monitor.update_monitor(chan.get().get_funding_txo().unwrap(), monitor_update) {
2470                                                 if was_frozen_for_monitor {
2471                                                         assert!(commitment_update.is_none() && closing_signed.is_none() && pending_forwards.is_empty() && pending_failures.is_empty());
2472                                                         return Err(MsgHandleErrInternal::ignore_no_close("Previous monitor update failure prevented responses to RAA"));
2473                                                 } else {
2474                                                         return_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::CommitmentFirst, false, commitment_update.is_some(), pending_forwards, pending_failures);
2475                                                 }
2476                                         }
2477                                         if let Some(updates) = commitment_update {
2478                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
2479                                                         node_id: their_node_id.clone(),
2480                                                         updates,
2481                                                 });
2482                                         }
2483                                         if let Some(msg) = closing_signed {
2484                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendClosingSigned {
2485                                                         node_id: their_node_id.clone(),
2486                                                         msg,
2487                                                 });
2488                                         }
2489                                         (pending_forwards, pending_failures, chan.get().get_short_channel_id().expect("RAA should only work on a short-id-available channel"))
2490                                 },
2491                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2492                         }
2493                 };
2494                 for failure in pending_failures.drain(..) {
2495                         self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), failure.0, &failure.1, failure.2);
2496                 }
2497                 self.forward_htlcs(&mut [(short_channel_id, pending_forwards)]);
2498
2499                 Ok(())
2500         }
2501
2502         fn internal_update_fee(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFee) -> Result<(), MsgHandleErrInternal> {
2503                 let mut channel_lock = self.channel_state.lock().unwrap();
2504                 let channel_state = &mut *channel_lock;
2505                 match channel_state.by_id.entry(msg.channel_id) {
2506                         hash_map::Entry::Occupied(mut chan) => {
2507                                 if chan.get().get_their_node_id() != *their_node_id {
2508                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2509                                 }
2510                                 try_chan_entry!(self, chan.get_mut().update_fee(&self.fee_estimator, &msg), channel_state, chan);
2511                         },
2512                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2513                 }
2514                 Ok(())
2515         }
2516
2517         fn internal_announcement_signatures(&self, their_node_id: &PublicKey, msg: &msgs::AnnouncementSignatures) -> Result<(), MsgHandleErrInternal> {
2518                 let mut channel_state_lock = self.channel_state.lock().unwrap();
2519                 let channel_state = &mut *channel_state_lock;
2520
2521                 match channel_state.by_id.entry(msg.channel_id) {
2522                         hash_map::Entry::Occupied(mut chan) => {
2523                                 if chan.get().get_their_node_id() != *their_node_id {
2524                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2525                                 }
2526                                 if !chan.get().is_usable() {
2527                                         return Err(MsgHandleErrInternal::from_no_close(LightningError{err: "Got an announcement_signatures before we were ready for it", action: msgs::ErrorAction::IgnoreError}));
2528                                 }
2529
2530                                 let our_node_id = self.get_our_node_id();
2531                                 let (announcement, our_bitcoin_sig) =
2532                                         try_chan_entry!(self, chan.get_mut().get_channel_announcement(our_node_id.clone(), self.genesis_hash.clone()), channel_state, chan);
2533
2534                                 let were_node_one = announcement.node_id_1 == our_node_id;
2535                                 let msghash = hash_to_message!(&Sha256dHash::hash(&announcement.encode()[..])[..]);
2536                                 if self.secp_ctx.verify(&msghash, &msg.node_signature, if were_node_one { &announcement.node_id_2 } else { &announcement.node_id_1 }).is_err() ||
2537                                                 self.secp_ctx.verify(&msghash, &msg.bitcoin_signature, if were_node_one { &announcement.bitcoin_key_2 } else { &announcement.bitcoin_key_1 }).is_err() {
2538                                         let chan_err: ChannelError = ChannelError::Close("Bad announcement_signatures node_signature");
2539                                         try_chan_entry!(self, Err(chan_err), channel_state, chan);
2540                                 }
2541
2542                                 let our_node_sig = self.secp_ctx.sign(&msghash, &self.our_network_key);
2543
2544                                 channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelAnnouncement {
2545                                         msg: msgs::ChannelAnnouncement {
2546                                                 node_signature_1: if were_node_one { our_node_sig } else { msg.node_signature },
2547                                                 node_signature_2: if were_node_one { msg.node_signature } else { our_node_sig },
2548                                                 bitcoin_signature_1: if were_node_one { our_bitcoin_sig } else { msg.bitcoin_signature },
2549                                                 bitcoin_signature_2: if were_node_one { msg.bitcoin_signature } else { our_bitcoin_sig },
2550                                                 contents: announcement,
2551                                         },
2552                                         update_msg: self.get_channel_update(chan.get()).unwrap(), // can only fail if we're not in a ready state
2553                                 });
2554                         },
2555                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2556                 }
2557                 Ok(())
2558         }
2559
2560         fn internal_channel_reestablish(&self, their_node_id: &PublicKey, msg: &msgs::ChannelReestablish) -> Result<(), MsgHandleErrInternal> {
2561                 let mut channel_state_lock = self.channel_state.lock().unwrap();
2562                 let channel_state = &mut *channel_state_lock;
2563
2564                 match channel_state.by_id.entry(msg.channel_id) {
2565                         hash_map::Entry::Occupied(mut chan) => {
2566                                 if chan.get().get_their_node_id() != *their_node_id {
2567                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2568                                 }
2569                                 let (funding_locked, revoke_and_ack, commitment_update, monitor_update_opt, mut order, shutdown) =
2570                                         try_chan_entry!(self, chan.get_mut().channel_reestablish(msg), channel_state, chan);
2571                                 if let Some(monitor_update) = monitor_update_opt {
2572                                         if let Err(e) = self.monitor.update_monitor(chan.get().get_funding_txo().unwrap(), monitor_update) {
2573                                                 // channel_reestablish doesn't guarantee the order it returns is sensical
2574                                                 // for the messages it returns, but if we're setting what messages to
2575                                                 // re-transmit on monitor update success, we need to make sure it is sane.
2576                                                 if revoke_and_ack.is_none() {
2577                                                         order = RAACommitmentOrder::CommitmentFirst;
2578                                                 }
2579                                                 if commitment_update.is_none() {
2580                                                         order = RAACommitmentOrder::RevokeAndACKFirst;
2581                                                 }
2582                                                 return_monitor_err!(self, e, channel_state, chan, order, revoke_and_ack.is_some(), commitment_update.is_some());
2583                                                 //TODO: Resend the funding_locked if needed once we get the monitor running again
2584                                         }
2585                                 }
2586                                 if let Some(msg) = funding_locked {
2587                                         channel_state.pending_msg_events.push(events::MessageSendEvent::SendFundingLocked {
2588                                                 node_id: their_node_id.clone(),
2589                                                 msg
2590                                         });
2591                                 }
2592                                 macro_rules! send_raa { () => {
2593                                         if let Some(msg) = revoke_and_ack {
2594                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendRevokeAndACK {
2595                                                         node_id: their_node_id.clone(),
2596                                                         msg
2597                                                 });
2598                                         }
2599                                 } }
2600                                 macro_rules! send_cu { () => {
2601                                         if let Some(updates) = commitment_update {
2602                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
2603                                                         node_id: their_node_id.clone(),
2604                                                         updates
2605                                                 });
2606                                         }
2607                                 } }
2608                                 match order {
2609                                         RAACommitmentOrder::RevokeAndACKFirst => {
2610                                                 send_raa!();
2611                                                 send_cu!();
2612                                         },
2613                                         RAACommitmentOrder::CommitmentFirst => {
2614                                                 send_cu!();
2615                                                 send_raa!();
2616                                         },
2617                                 }
2618                                 if let Some(msg) = shutdown {
2619                                         channel_state.pending_msg_events.push(events::MessageSendEvent::SendShutdown {
2620                                                 node_id: their_node_id.clone(),
2621                                                 msg,
2622                                         });
2623                                 }
2624                                 Ok(())
2625                         },
2626                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2627                 }
2628         }
2629
2630         /// Begin Update fee process. Allowed only on an outbound channel.
2631         /// If successful, will generate a UpdateHTLCs event, so you should probably poll
2632         /// PeerManager::process_events afterwards.
2633         /// Note: This API is likely to change!
2634         #[doc(hidden)]
2635         pub fn update_fee(&self, channel_id: [u8;32], feerate_per_kw: u64) -> Result<(), APIError> {
2636                 let _ = self.total_consistency_lock.read().unwrap();
2637                 let their_node_id;
2638                 let err: Result<(), _> = loop {
2639                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2640                         let channel_state = &mut *channel_state_lock;
2641
2642                         match channel_state.by_id.entry(channel_id) {
2643                                 hash_map::Entry::Vacant(_) => return Err(APIError::APIMisuseError{err: "Failed to find corresponding channel"}),
2644                                 hash_map::Entry::Occupied(mut chan) => {
2645                                         if !chan.get().is_outbound() {
2646                                                 return Err(APIError::APIMisuseError{err: "update_fee cannot be sent for an inbound channel"});
2647                                         }
2648                                         if chan.get().is_awaiting_monitor_update() {
2649                                                 return Err(APIError::MonitorUpdateFailed);
2650                                         }
2651                                         if !chan.get().is_live() {
2652                                                 return Err(APIError::ChannelUnavailable{err: "Channel is either not yet fully established or peer is currently disconnected"});
2653                                         }
2654                                         their_node_id = chan.get().get_their_node_id();
2655                                         if let Some((update_fee, commitment_signed, monitor_update)) =
2656                                                         break_chan_entry!(self, chan.get_mut().send_update_fee_and_commit(feerate_per_kw), channel_state, chan)
2657                                         {
2658                                                 if let Err(_e) = self.monitor.update_monitor(chan.get().get_funding_txo().unwrap(), monitor_update) {
2659                                                         unimplemented!();
2660                                                 }
2661                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
2662                                                         node_id: chan.get().get_their_node_id(),
2663                                                         updates: msgs::CommitmentUpdate {
2664                                                                 update_add_htlcs: Vec::new(),
2665                                                                 update_fulfill_htlcs: Vec::new(),
2666                                                                 update_fail_htlcs: Vec::new(),
2667                                                                 update_fail_malformed_htlcs: Vec::new(),
2668                                                                 update_fee: Some(update_fee),
2669                                                                 commitment_signed,
2670                                                         },
2671                                                 });
2672                                         }
2673                                 },
2674                         }
2675                         return Ok(())
2676                 };
2677
2678                 match handle_error!(self, err, their_node_id) {
2679                         Ok(_) => unreachable!(),
2680                         Err(e) => { Err(APIError::APIMisuseError { err: e.err })}
2681                 }
2682         }
2683 }
2684
2685 impl<ChanSigner: ChannelKeys, M: Deref, T: Deref, K: Deref, F: Deref> events::MessageSendEventsProvider for ChannelManager<ChanSigner, M, T, K, F>
2686         where M::Target: ManyChannelMonitor<ChanSigner>,
2687         T::Target: BroadcasterInterface,
2688         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
2689         F::Target: FeeEstimator,
2690 {
2691         fn get_and_clear_pending_msg_events(&self) -> Vec<events::MessageSendEvent> {
2692                 // TODO: Event release to users and serialization is currently race-y: it's very easy for a
2693                 // user to serialize a ChannelManager with pending events in it and lose those events on
2694                 // restart. This is doubly true for the fail/fulfill-backs from monitor events!
2695                 {
2696                         //TODO: This behavior should be documented.
2697                         for htlc_update in self.monitor.get_and_clear_pending_htlcs_updated() {
2698                                 if let Some(preimage) = htlc_update.payment_preimage {
2699                                         log_trace!(self, "Claiming HTLC with preimage {} from our monitor", log_bytes!(preimage.0));
2700                                         self.claim_funds_internal(self.channel_state.lock().unwrap(), htlc_update.source, preimage);
2701                                 } else {
2702                                         log_trace!(self, "Failing HTLC with hash {} from our monitor", log_bytes!(htlc_update.payment_hash.0));
2703                                         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() });
2704                                 }
2705                         }
2706                 }
2707
2708                 let mut ret = Vec::new();
2709                 let mut channel_state = self.channel_state.lock().unwrap();
2710                 mem::swap(&mut ret, &mut channel_state.pending_msg_events);
2711                 ret
2712         }
2713 }
2714
2715 impl<ChanSigner: ChannelKeys, M: Deref, T: Deref, K: Deref, F: Deref> events::EventsProvider for ChannelManager<ChanSigner, M, T, K, F>
2716         where M::Target: ManyChannelMonitor<ChanSigner>,
2717         T::Target: BroadcasterInterface,
2718         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
2719         F::Target: FeeEstimator,
2720 {
2721         fn get_and_clear_pending_events(&self) -> Vec<events::Event> {
2722                 // TODO: Event release to users and serialization is currently race-y: it's very easy for a
2723                 // user to serialize a ChannelManager with pending events in it and lose those events on
2724                 // restart. This is doubly true for the fail/fulfill-backs from monitor events!
2725                 {
2726                         //TODO: This behavior should be documented.
2727                         for htlc_update in self.monitor.get_and_clear_pending_htlcs_updated() {
2728                                 if let Some(preimage) = htlc_update.payment_preimage {
2729                                         log_trace!(self, "Claiming HTLC with preimage {} from our monitor", log_bytes!(preimage.0));
2730                                         self.claim_funds_internal(self.channel_state.lock().unwrap(), htlc_update.source, preimage);
2731                                 } else {
2732                                         log_trace!(self, "Failing HTLC with hash {} from our monitor", log_bytes!(htlc_update.payment_hash.0));
2733                                         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() });
2734                                 }
2735                         }
2736                 }
2737
2738                 let mut ret = Vec::new();
2739                 let mut pending_events = self.pending_events.lock().unwrap();
2740                 mem::swap(&mut ret, &mut *pending_events);
2741                 ret
2742         }
2743 }
2744
2745 impl<ChanSigner: ChannelKeys, M: Deref + Sync + Send, T: Deref + Sync + Send, K: Deref + Sync + Send, F: Deref + Sync + Send>
2746         ChainListener for ChannelManager<ChanSigner, M, T, K, F>
2747         where M::Target: ManyChannelMonitor<ChanSigner>,
2748         T::Target: BroadcasterInterface,
2749         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
2750         F::Target: FeeEstimator,
2751 {
2752         fn block_connected(&self, header: &BlockHeader, height: u32, txn_matched: &[&Transaction], indexes_of_txn_matched: &[u32]) {
2753                 let header_hash = header.bitcoin_hash();
2754                 log_trace!(self, "Block {} at height {} connected with {} txn matched", header_hash, height, txn_matched.len());
2755                 let _ = self.total_consistency_lock.read().unwrap();
2756                 let mut failed_channels = Vec::new();
2757                 {
2758                         let mut channel_lock = self.channel_state.lock().unwrap();
2759                         let channel_state = &mut *channel_lock;
2760                         let short_to_id = &mut channel_state.short_to_id;
2761                         let pending_msg_events = &mut channel_state.pending_msg_events;
2762                         channel_state.by_id.retain(|_, channel| {
2763                                 let chan_res = channel.block_connected(header, height, txn_matched, indexes_of_txn_matched);
2764                                 if let Ok(Some(funding_locked)) = chan_res {
2765                                         pending_msg_events.push(events::MessageSendEvent::SendFundingLocked {
2766                                                 node_id: channel.get_their_node_id(),
2767                                                 msg: funding_locked,
2768                                         });
2769                                         if let Some(announcement_sigs) = self.get_announcement_sigs(channel) {
2770                                                 log_trace!(self, "Sending funding_locked and announcement_signatures for {}", log_bytes!(channel.channel_id()));
2771                                                 pending_msg_events.push(events::MessageSendEvent::SendAnnouncementSignatures {
2772                                                         node_id: channel.get_their_node_id(),
2773                                                         msg: announcement_sigs,
2774                                                 });
2775                                         } else {
2776                                                 log_trace!(self, "Sending funding_locked WITHOUT announcement_signatures for {}", log_bytes!(channel.channel_id()));
2777                                         }
2778                                         short_to_id.insert(channel.get_short_channel_id().unwrap(), channel.channel_id());
2779                                 } else if let Err(e) = chan_res {
2780                                         pending_msg_events.push(events::MessageSendEvent::HandleError {
2781                                                 node_id: channel.get_their_node_id(),
2782                                                 action: msgs::ErrorAction::SendErrorMessage { msg: e },
2783                                         });
2784                                         return false;
2785                                 }
2786                                 if let Some(funding_txo) = channel.get_funding_txo() {
2787                                         for tx in txn_matched {
2788                                                 for inp in tx.input.iter() {
2789                                                         if inp.previous_output == funding_txo.into_bitcoin_outpoint() {
2790                                                                 log_trace!(self, "Detected channel-closing tx {} spending {}:{}, closing channel {}", tx.txid(), inp.previous_output.txid, inp.previous_output.vout, log_bytes!(channel.channel_id()));
2791                                                                 if let Some(short_id) = channel.get_short_channel_id() {
2792                                                                         short_to_id.remove(&short_id);
2793                                                                 }
2794                                                                 // It looks like our counterparty went on-chain. We go ahead and
2795                                                                 // broadcast our latest local state as well here, just in case its
2796                                                                 // some kind of SPV attack, though we expect these to be dropped.
2797                                                                 failed_channels.push(channel.force_shutdown(true));
2798                                                                 if let Ok(update) = self.get_channel_update(&channel) {
2799                                                                         pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
2800                                                                                 msg: update
2801                                                                         });
2802                                                                 }
2803                                                                 return false;
2804                                                         }
2805                                                 }
2806                                         }
2807                                 }
2808                                 if channel.is_funding_initiated() && channel.channel_monitor().would_broadcast_at_height(height) {
2809                                         if let Some(short_id) = channel.get_short_channel_id() {
2810                                                 short_to_id.remove(&short_id);
2811                                         }
2812                                         // If would_broadcast_at_height() is true, the channel_monitor will broadcast
2813                                         // the latest local tx for us, so we should skip that here (it doesn't really
2814                                         // hurt anything, but does make tests a bit simpler).
2815                                         failed_channels.push(channel.force_shutdown(false));
2816                                         if let Ok(update) = self.get_channel_update(&channel) {
2817                                                 pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
2818                                                         msg: update
2819                                                 });
2820                                         }
2821                                         return false;
2822                                 }
2823                                 true
2824                         });
2825                 }
2826                 for failure in failed_channels.drain(..) {
2827                         self.finish_force_close_channel(failure);
2828                 }
2829                 self.latest_block_height.store(height as usize, Ordering::Release);
2830                 *self.last_block_hash.try_lock().expect("block_(dis)connected must not be called in parallel") = header_hash;
2831                 loop {
2832                         // Update last_node_announcement_serial to be the max of its current value and the
2833                         // block timestamp. This should keep us close to the current time without relying on
2834                         // having an explicit local time source.
2835                         // Just in case we end up in a race, we loop until we either successfully update
2836                         // last_node_announcement_serial or decide we don't need to.
2837                         let old_serial = self.last_node_announcement_serial.load(Ordering::Acquire);
2838                         if old_serial >= header.time as usize { break; }
2839                         if self.last_node_announcement_serial.compare_exchange(old_serial, header.time as usize, Ordering::AcqRel, Ordering::Relaxed).is_ok() {
2840                                 break;
2841                         }
2842                 }
2843         }
2844
2845         /// We force-close the channel without letting our counterparty participate in the shutdown
2846         fn block_disconnected(&self, header: &BlockHeader, _: u32) {
2847                 let _ = self.total_consistency_lock.read().unwrap();
2848                 let mut failed_channels = Vec::new();
2849                 {
2850                         let mut channel_lock = self.channel_state.lock().unwrap();
2851                         let channel_state = &mut *channel_lock;
2852                         let short_to_id = &mut channel_state.short_to_id;
2853                         let pending_msg_events = &mut channel_state.pending_msg_events;
2854                         channel_state.by_id.retain(|_,  v| {
2855                                 if v.block_disconnected(header) {
2856                                         if let Some(short_id) = v.get_short_channel_id() {
2857                                                 short_to_id.remove(&short_id);
2858                                         }
2859                                         failed_channels.push(v.force_shutdown(true));
2860                                         if let Ok(update) = self.get_channel_update(&v) {
2861                                                 pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
2862                                                         msg: update
2863                                                 });
2864                                         }
2865                                         false
2866                                 } else {
2867                                         true
2868                                 }
2869                         });
2870                 }
2871                 for failure in failed_channels.drain(..) {
2872                         self.finish_force_close_channel(failure);
2873                 }
2874                 self.latest_block_height.fetch_sub(1, Ordering::AcqRel);
2875                 *self.last_block_hash.try_lock().expect("block_(dis)connected must not be called in parallel") = header.bitcoin_hash();
2876         }
2877 }
2878
2879 impl<ChanSigner: ChannelKeys, M: Deref + Sync + Send, T: Deref + Sync + Send, K: Deref + Sync + Send, F: Deref + Sync + Send>
2880         ChannelMessageHandler for ChannelManager<ChanSigner, M, T, K, F>
2881         where M::Target: ManyChannelMonitor<ChanSigner>,
2882         T::Target: BroadcasterInterface,
2883         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
2884         F::Target: FeeEstimator,
2885 {
2886         fn handle_open_channel(&self, their_node_id: &PublicKey, their_features: InitFeatures, msg: &msgs::OpenChannel) {
2887                 let _ = self.total_consistency_lock.read().unwrap();
2888                 let _ = handle_error!(self, self.internal_open_channel(their_node_id, their_features, msg), *their_node_id);
2889         }
2890
2891         fn handle_accept_channel(&self, their_node_id: &PublicKey, their_features: InitFeatures, msg: &msgs::AcceptChannel) {
2892                 let _ = self.total_consistency_lock.read().unwrap();
2893                 let _ = handle_error!(self, self.internal_accept_channel(their_node_id, their_features, msg), *their_node_id);
2894         }
2895
2896         fn handle_funding_created(&self, their_node_id: &PublicKey, msg: &msgs::FundingCreated) {
2897                 let _ = self.total_consistency_lock.read().unwrap();
2898                 let _ = handle_error!(self, self.internal_funding_created(their_node_id, msg), *their_node_id);
2899         }
2900
2901         fn handle_funding_signed(&self, their_node_id: &PublicKey, msg: &msgs::FundingSigned) {
2902                 let _ = self.total_consistency_lock.read().unwrap();
2903                 let _ = handle_error!(self, self.internal_funding_signed(their_node_id, msg), *their_node_id);
2904         }
2905
2906         fn handle_funding_locked(&self, their_node_id: &PublicKey, msg: &msgs::FundingLocked) {
2907                 let _ = self.total_consistency_lock.read().unwrap();
2908                 let _ = handle_error!(self, self.internal_funding_locked(their_node_id, msg), *their_node_id);
2909         }
2910
2911         fn handle_shutdown(&self, their_node_id: &PublicKey, msg: &msgs::Shutdown) {
2912                 let _ = self.total_consistency_lock.read().unwrap();
2913                 let _ = handle_error!(self, self.internal_shutdown(their_node_id, msg), *their_node_id);
2914         }
2915
2916         fn handle_closing_signed(&self, their_node_id: &PublicKey, msg: &msgs::ClosingSigned) {
2917                 let _ = self.total_consistency_lock.read().unwrap();
2918                 let _ = handle_error!(self, self.internal_closing_signed(their_node_id, msg), *their_node_id);
2919         }
2920
2921         fn handle_update_add_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateAddHTLC) {
2922                 let _ = self.total_consistency_lock.read().unwrap();
2923                 let _ = handle_error!(self, self.internal_update_add_htlc(their_node_id, msg), *their_node_id);
2924         }
2925
2926         fn handle_update_fulfill_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFulfillHTLC) {
2927                 let _ = self.total_consistency_lock.read().unwrap();
2928                 let _ = handle_error!(self, self.internal_update_fulfill_htlc(their_node_id, msg), *their_node_id);
2929         }
2930
2931         fn handle_update_fail_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFailHTLC) {
2932                 let _ = self.total_consistency_lock.read().unwrap();
2933                 let _ = handle_error!(self, self.internal_update_fail_htlc(their_node_id, msg), *their_node_id);
2934         }
2935
2936         fn handle_update_fail_malformed_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFailMalformedHTLC) {
2937                 let _ = self.total_consistency_lock.read().unwrap();
2938                 let _ = handle_error!(self, self.internal_update_fail_malformed_htlc(their_node_id, msg), *their_node_id);
2939         }
2940
2941         fn handle_commitment_signed(&self, their_node_id: &PublicKey, msg: &msgs::CommitmentSigned) {
2942                 let _ = self.total_consistency_lock.read().unwrap();
2943                 let _ = handle_error!(self, self.internal_commitment_signed(their_node_id, msg), *their_node_id);
2944         }
2945
2946         fn handle_revoke_and_ack(&self, their_node_id: &PublicKey, msg: &msgs::RevokeAndACK) {
2947                 let _ = self.total_consistency_lock.read().unwrap();
2948                 let _ = handle_error!(self, self.internal_revoke_and_ack(their_node_id, msg), *their_node_id);
2949         }
2950
2951         fn handle_update_fee(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFee) {
2952                 let _ = self.total_consistency_lock.read().unwrap();
2953                 let _ = handle_error!(self, self.internal_update_fee(their_node_id, msg), *their_node_id);
2954         }
2955
2956         fn handle_announcement_signatures(&self, their_node_id: &PublicKey, msg: &msgs::AnnouncementSignatures) {
2957                 let _ = self.total_consistency_lock.read().unwrap();
2958                 let _ = handle_error!(self, self.internal_announcement_signatures(their_node_id, msg), *their_node_id);
2959         }
2960
2961         fn handle_channel_reestablish(&self, their_node_id: &PublicKey, msg: &msgs::ChannelReestablish) {
2962                 let _ = self.total_consistency_lock.read().unwrap();
2963                 let _ = handle_error!(self, self.internal_channel_reestablish(their_node_id, msg), *their_node_id);
2964         }
2965
2966         fn peer_disconnected(&self, their_node_id: &PublicKey, no_connection_possible: bool) {
2967                 let _ = self.total_consistency_lock.read().unwrap();
2968                 let mut failed_channels = Vec::new();
2969                 let mut failed_payments = Vec::new();
2970                 let mut no_channels_remain = true;
2971                 {
2972                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2973                         let channel_state = &mut *channel_state_lock;
2974                         let short_to_id = &mut channel_state.short_to_id;
2975                         let pending_msg_events = &mut channel_state.pending_msg_events;
2976                         if no_connection_possible {
2977                                 log_debug!(self, "Failing all channels with {} due to no_connection_possible", log_pubkey!(their_node_id));
2978                                 channel_state.by_id.retain(|_, chan| {
2979                                         if chan.get_their_node_id() == *their_node_id {
2980                                                 if let Some(short_id) = chan.get_short_channel_id() {
2981                                                         short_to_id.remove(&short_id);
2982                                                 }
2983                                                 failed_channels.push(chan.force_shutdown(true));
2984                                                 if let Ok(update) = self.get_channel_update(&chan) {
2985                                                         pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
2986                                                                 msg: update
2987                                                         });
2988                                                 }
2989                                                 false
2990                                         } else {
2991                                                 true
2992                                         }
2993                                 });
2994                         } else {
2995                                 log_debug!(self, "Marking channels with {} disconnected and generating channel_updates", log_pubkey!(their_node_id));
2996                                 channel_state.by_id.retain(|_, chan| {
2997                                         if chan.get_their_node_id() == *their_node_id {
2998                                                 let failed_adds = chan.remove_uncommitted_htlcs_and_mark_paused();
2999                                                 chan.to_disabled_marked();
3000                                                 if !failed_adds.is_empty() {
3001                                                         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
3002                                                         failed_payments.push((chan_update, failed_adds));
3003                                                 }
3004                                                 if chan.is_shutdown() {
3005                                                         if let Some(short_id) = chan.get_short_channel_id() {
3006                                                                 short_to_id.remove(&short_id);
3007                                                         }
3008                                                         return false;
3009                                                 } else {
3010                                                         no_channels_remain = false;
3011                                                 }
3012                                         }
3013                                         true
3014                                 })
3015                         }
3016                         pending_msg_events.retain(|msg| {
3017                                 match msg {
3018                                         &events::MessageSendEvent::SendAcceptChannel { ref node_id, .. } => node_id != their_node_id,
3019                                         &events::MessageSendEvent::SendOpenChannel { ref node_id, .. } => node_id != their_node_id,
3020                                         &events::MessageSendEvent::SendFundingCreated { ref node_id, .. } => node_id != their_node_id,
3021                                         &events::MessageSendEvent::SendFundingSigned { ref node_id, .. } => node_id != their_node_id,
3022                                         &events::MessageSendEvent::SendFundingLocked { ref node_id, .. } => node_id != their_node_id,
3023                                         &events::MessageSendEvent::SendAnnouncementSignatures { ref node_id, .. } => node_id != their_node_id,
3024                                         &events::MessageSendEvent::UpdateHTLCs { ref node_id, .. } => node_id != their_node_id,
3025                                         &events::MessageSendEvent::SendRevokeAndACK { ref node_id, .. } => node_id != their_node_id,
3026                                         &events::MessageSendEvent::SendClosingSigned { ref node_id, .. } => node_id != their_node_id,
3027                                         &events::MessageSendEvent::SendShutdown { ref node_id, .. } => node_id != their_node_id,
3028                                         &events::MessageSendEvent::SendChannelReestablish { ref node_id, .. } => node_id != their_node_id,
3029                                         &events::MessageSendEvent::BroadcastChannelAnnouncement { .. } => true,
3030                                         &events::MessageSendEvent::BroadcastNodeAnnouncement { .. } => true,
3031                                         &events::MessageSendEvent::BroadcastChannelUpdate { .. } => true,
3032                                         &events::MessageSendEvent::HandleError { ref node_id, .. } => node_id != their_node_id,
3033                                         &events::MessageSendEvent::PaymentFailureNetworkUpdate { .. } => true,
3034                                 }
3035                         });
3036                 }
3037                 if no_channels_remain {
3038                         self.per_peer_state.write().unwrap().remove(their_node_id);
3039                 }
3040
3041                 for failure in failed_channels.drain(..) {
3042                         self.finish_force_close_channel(failure);
3043                 }
3044                 for (chan_update, mut htlc_sources) in failed_payments {
3045                         for (htlc_source, payment_hash) in htlc_sources.drain(..) {
3046                                 self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), htlc_source, &payment_hash, HTLCFailReason::Reason { failure_code: 0x1000 | 7, data: chan_update.clone() });
3047                         }
3048                 }
3049         }
3050
3051         fn peer_connected(&self, their_node_id: &PublicKey, init_msg: &msgs::Init) {
3052                 log_debug!(self, "Generating channel_reestablish events for {}", log_pubkey!(their_node_id));
3053
3054                 let _ = self.total_consistency_lock.read().unwrap();
3055
3056                 {
3057                         let mut peer_state_lock = self.per_peer_state.write().unwrap();
3058                         match peer_state_lock.entry(their_node_id.clone()) {
3059                                 hash_map::Entry::Vacant(e) => {
3060                                         e.insert(Mutex::new(PeerState {
3061                                                 latest_features: init_msg.features.clone(),
3062                                         }));
3063                                 },
3064                                 hash_map::Entry::Occupied(e) => {
3065                                         e.get().lock().unwrap().latest_features = init_msg.features.clone();
3066                                 },
3067                         }
3068                 }
3069
3070                 let mut channel_state_lock = self.channel_state.lock().unwrap();
3071                 let channel_state = &mut *channel_state_lock;
3072                 let pending_msg_events = &mut channel_state.pending_msg_events;
3073                 channel_state.by_id.retain(|_, chan| {
3074                         if chan.get_their_node_id() == *their_node_id {
3075                                 if !chan.have_received_message() {
3076                                         // If we created this (outbound) channel while we were disconnected from the
3077                                         // peer we probably failed to send the open_channel message, which is now
3078                                         // lost. We can't have had anything pending related to this channel, so we just
3079                                         // drop it.
3080                                         false
3081                                 } else {
3082                                         pending_msg_events.push(events::MessageSendEvent::SendChannelReestablish {
3083                                                 node_id: chan.get_their_node_id(),
3084                                                 msg: chan.get_channel_reestablish(),
3085                                         });
3086                                         true
3087                                 }
3088                         } else { true }
3089                 });
3090                 //TODO: Also re-broadcast announcement_signatures
3091         }
3092
3093         fn handle_error(&self, their_node_id: &PublicKey, msg: &msgs::ErrorMessage) {
3094                 let _ = self.total_consistency_lock.read().unwrap();
3095
3096                 if msg.channel_id == [0; 32] {
3097                         for chan in self.list_channels() {
3098                                 if chan.remote_network_id == *their_node_id {
3099                                         self.force_close_channel(&chan.channel_id);
3100                                 }
3101                         }
3102                 } else {
3103                         self.force_close_channel(&msg.channel_id);
3104                 }
3105         }
3106 }
3107
3108 const SERIALIZATION_VERSION: u8 = 1;
3109 const MIN_SERIALIZATION_VERSION: u8 = 1;
3110
3111 impl Writeable for PendingHTLCInfo {
3112         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3113                 match &self.routing {
3114                         &PendingHTLCRouting::Forward { ref onion_packet, ref short_channel_id } => {
3115                                 0u8.write(writer)?;
3116                                 onion_packet.write(writer)?;
3117                                 short_channel_id.write(writer)?;
3118                         },
3119                         &PendingHTLCRouting::Receive { ref payment_data } => {
3120                                 1u8.write(writer)?;
3121                                 payment_data.write(writer)?;
3122                         },
3123                 }
3124                 self.incoming_shared_secret.write(writer)?;
3125                 self.payment_hash.write(writer)?;
3126                 self.amt_to_forward.write(writer)?;
3127                 self.outgoing_cltv_value.write(writer)?;
3128                 Ok(())
3129         }
3130 }
3131
3132 impl Readable for PendingHTLCInfo {
3133         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<PendingHTLCInfo, DecodeError> {
3134                 Ok(PendingHTLCInfo {
3135                         routing: match Readable::read(reader)? {
3136                                 0u8 => PendingHTLCRouting::Forward {
3137                                         onion_packet: Readable::read(reader)?,
3138                                         short_channel_id: Readable::read(reader)?,
3139                                 },
3140                                 1u8 => PendingHTLCRouting::Receive {
3141                                         payment_data: Readable::read(reader)?,
3142                                 },
3143                                 _ => return Err(DecodeError::InvalidValue),
3144                         },
3145                         incoming_shared_secret: Readable::read(reader)?,
3146                         payment_hash: Readable::read(reader)?,
3147                         amt_to_forward: Readable::read(reader)?,
3148                         outgoing_cltv_value: Readable::read(reader)?,
3149                 })
3150         }
3151 }
3152
3153 impl Writeable for HTLCFailureMsg {
3154         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3155                 match self {
3156                         &HTLCFailureMsg::Relay(ref fail_msg) => {
3157                                 0u8.write(writer)?;
3158                                 fail_msg.write(writer)?;
3159                         },
3160                         &HTLCFailureMsg::Malformed(ref fail_msg) => {
3161                                 1u8.write(writer)?;
3162                                 fail_msg.write(writer)?;
3163                         }
3164                 }
3165                 Ok(())
3166         }
3167 }
3168
3169 impl Readable for HTLCFailureMsg {
3170         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<HTLCFailureMsg, DecodeError> {
3171                 match <u8 as Readable>::read(reader)? {
3172                         0 => Ok(HTLCFailureMsg::Relay(Readable::read(reader)?)),
3173                         1 => Ok(HTLCFailureMsg::Malformed(Readable::read(reader)?)),
3174                         _ => Err(DecodeError::InvalidValue),
3175                 }
3176         }
3177 }
3178
3179 impl Writeable for PendingHTLCStatus {
3180         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3181                 match self {
3182                         &PendingHTLCStatus::Forward(ref forward_info) => {
3183                                 0u8.write(writer)?;
3184                                 forward_info.write(writer)?;
3185                         },
3186                         &PendingHTLCStatus::Fail(ref fail_msg) => {
3187                                 1u8.write(writer)?;
3188                                 fail_msg.write(writer)?;
3189                         }
3190                 }
3191                 Ok(())
3192         }
3193 }
3194
3195 impl Readable for PendingHTLCStatus {
3196         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<PendingHTLCStatus, DecodeError> {
3197                 match <u8 as Readable>::read(reader)? {
3198                         0 => Ok(PendingHTLCStatus::Forward(Readable::read(reader)?)),
3199                         1 => Ok(PendingHTLCStatus::Fail(Readable::read(reader)?)),
3200                         _ => Err(DecodeError::InvalidValue),
3201                 }
3202         }
3203 }
3204
3205 impl_writeable!(HTLCPreviousHopData, 0, {
3206         short_channel_id,
3207         htlc_id,
3208         incoming_packet_shared_secret
3209 });
3210
3211 impl_writeable!(ClaimableHTLC, 0, {
3212         prev_hop,
3213         value,
3214         payment_data
3215 });
3216
3217 impl Writeable for HTLCSource {
3218         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3219                 match self {
3220                         &HTLCSource::PreviousHopData(ref hop_data) => {
3221                                 0u8.write(writer)?;
3222                                 hop_data.write(writer)?;
3223                         },
3224                         &HTLCSource::OutboundRoute { ref route, ref session_priv, ref first_hop_htlc_msat } => {
3225                                 1u8.write(writer)?;
3226                                 route.write(writer)?;
3227                                 session_priv.write(writer)?;
3228                                 first_hop_htlc_msat.write(writer)?;
3229                         }
3230                 }
3231                 Ok(())
3232         }
3233 }
3234
3235 impl Readable for HTLCSource {
3236         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<HTLCSource, DecodeError> {
3237                 match <u8 as Readable>::read(reader)? {
3238                         0 => Ok(HTLCSource::PreviousHopData(Readable::read(reader)?)),
3239                         1 => Ok(HTLCSource::OutboundRoute {
3240                                 route: Readable::read(reader)?,
3241                                 session_priv: Readable::read(reader)?,
3242                                 first_hop_htlc_msat: Readable::read(reader)?,
3243                         }),
3244                         _ => Err(DecodeError::InvalidValue),
3245                 }
3246         }
3247 }
3248
3249 impl Writeable for HTLCFailReason {
3250         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3251                 match self {
3252                         &HTLCFailReason::LightningError { ref err } => {
3253                                 0u8.write(writer)?;
3254                                 err.write(writer)?;
3255                         },
3256                         &HTLCFailReason::Reason { ref failure_code, ref data } => {
3257                                 1u8.write(writer)?;
3258                                 failure_code.write(writer)?;
3259                                 data.write(writer)?;
3260                         }
3261                 }
3262                 Ok(())
3263         }
3264 }
3265
3266 impl Readable for HTLCFailReason {
3267         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<HTLCFailReason, DecodeError> {
3268                 match <u8 as Readable>::read(reader)? {
3269                         0 => Ok(HTLCFailReason::LightningError { err: Readable::read(reader)? }),
3270                         1 => Ok(HTLCFailReason::Reason {
3271                                 failure_code: Readable::read(reader)?,
3272                                 data: Readable::read(reader)?,
3273                         }),
3274                         _ => Err(DecodeError::InvalidValue),
3275                 }
3276         }
3277 }
3278
3279 impl Writeable for HTLCForwardInfo {
3280         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3281                 match self {
3282                         &HTLCForwardInfo::AddHTLC { ref prev_short_channel_id, ref prev_htlc_id, ref forward_info } => {
3283                                 0u8.write(writer)?;
3284                                 prev_short_channel_id.write(writer)?;
3285                                 prev_htlc_id.write(writer)?;
3286                                 forward_info.write(writer)?;
3287                         },
3288                         &HTLCForwardInfo::FailHTLC { ref htlc_id, ref err_packet } => {
3289                                 1u8.write(writer)?;
3290                                 htlc_id.write(writer)?;
3291                                 err_packet.write(writer)?;
3292                         },
3293                 }
3294                 Ok(())
3295         }
3296 }
3297
3298 impl Readable for HTLCForwardInfo {
3299         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<HTLCForwardInfo, DecodeError> {
3300                 match <u8 as Readable>::read(reader)? {
3301                         0 => Ok(HTLCForwardInfo::AddHTLC {
3302                                 prev_short_channel_id: Readable::read(reader)?,
3303                                 prev_htlc_id: Readable::read(reader)?,
3304                                 forward_info: Readable::read(reader)?,
3305                         }),
3306                         1 => Ok(HTLCForwardInfo::FailHTLC {
3307                                 htlc_id: Readable::read(reader)?,
3308                                 err_packet: Readable::read(reader)?,
3309                         }),
3310                         _ => Err(DecodeError::InvalidValue),
3311                 }
3312         }
3313 }
3314
3315 impl<ChanSigner: ChannelKeys + Writeable, M: Deref, T: Deref, K: Deref, F: Deref> Writeable for ChannelManager<ChanSigner, M, T, K, F>
3316         where M::Target: ManyChannelMonitor<ChanSigner>,
3317         T::Target: BroadcasterInterface,
3318         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
3319         F::Target: FeeEstimator,
3320 {
3321         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3322                 let _ = self.total_consistency_lock.write().unwrap();
3323
3324                 writer.write_all(&[SERIALIZATION_VERSION; 1])?;
3325                 writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
3326
3327                 self.genesis_hash.write(writer)?;
3328                 (self.latest_block_height.load(Ordering::Acquire) as u32).write(writer)?;
3329                 self.last_block_hash.lock().unwrap().write(writer)?;
3330
3331                 let channel_state = self.channel_state.lock().unwrap();
3332                 let mut unfunded_channels = 0;
3333                 for (_, channel) in channel_state.by_id.iter() {
3334                         if !channel.is_funding_initiated() {
3335                                 unfunded_channels += 1;
3336                         }
3337                 }
3338                 ((channel_state.by_id.len() - unfunded_channels) as u64).write(writer)?;
3339                 for (_, channel) in channel_state.by_id.iter() {
3340                         if channel.is_funding_initiated() {
3341                                 channel.write(writer)?;
3342                         }
3343                 }
3344
3345                 (channel_state.forward_htlcs.len() as u64).write(writer)?;
3346                 for (short_channel_id, pending_forwards) in channel_state.forward_htlcs.iter() {
3347                         short_channel_id.write(writer)?;
3348                         (pending_forwards.len() as u64).write(writer)?;
3349                         for forward in pending_forwards {
3350                                 forward.write(writer)?;
3351                         }
3352                 }
3353
3354                 (channel_state.claimable_htlcs.len() as u64).write(writer)?;
3355                 for (payment_hash, previous_hops) in channel_state.claimable_htlcs.iter() {
3356                         payment_hash.write(writer)?;
3357                         (previous_hops.len() as u64).write(writer)?;
3358                         for htlc in previous_hops.iter() {
3359                                 htlc.write(writer)?;
3360                         }
3361                 }
3362
3363                 let per_peer_state = self.per_peer_state.write().unwrap();
3364                 (per_peer_state.len() as u64).write(writer)?;
3365                 for (peer_pubkey, peer_state_mutex) in per_peer_state.iter() {
3366                         peer_pubkey.write(writer)?;
3367                         let peer_state = peer_state_mutex.lock().unwrap();
3368                         peer_state.latest_features.write(writer)?;
3369                 }
3370
3371                 (self.last_node_announcement_serial.load(Ordering::Acquire) as u32).write(writer)?;
3372
3373                 Ok(())
3374         }
3375 }
3376
3377 /// Arguments for the creation of a ChannelManager that are not deserialized.
3378 ///
3379 /// At a high-level, the process for deserializing a ChannelManager and resuming normal operation
3380 /// is:
3381 /// 1) Deserialize all stored ChannelMonitors.
3382 /// 2) Deserialize the ChannelManager by filling in this struct and calling <(Sha256dHash,
3383 ///    ChannelManager)>::read(reader, args).
3384 ///    This may result in closing some Channels if the ChannelMonitor is newer than the stored
3385 ///    ChannelManager state to ensure no loss of funds. Thus, transactions may be broadcasted.
3386 /// 3) Register all relevant ChannelMonitor outpoints with your chain watch mechanism using
3387 ///    ChannelMonitor::get_monitored_outpoints and ChannelMonitor::get_funding_txo().
3388 /// 4) Reconnect blocks on your ChannelMonitors.
3389 /// 5) Move the ChannelMonitors into your local ManyChannelMonitor.
3390 /// 6) Disconnect/connect blocks on the ChannelManager.
3391 /// 7) Register the new ChannelManager with your ChainWatchInterface.
3392 pub struct ChannelManagerReadArgs<'a, ChanSigner: 'a + ChannelKeys, M: Deref, T: Deref, K: Deref, F: Deref>
3393         where M::Target: ManyChannelMonitor<ChanSigner>,
3394         T::Target: BroadcasterInterface,
3395         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
3396         F::Target: FeeEstimator,
3397 {
3398
3399         /// The keys provider which will give us relevant keys. Some keys will be loaded during
3400         /// deserialization.
3401         pub keys_manager: K,
3402
3403         /// The fee_estimator for use in the ChannelManager in the future.
3404         ///
3405         /// No calls to the FeeEstimator will be made during deserialization.
3406         pub fee_estimator: F,
3407         /// The ManyChannelMonitor for use in the ChannelManager in the future.
3408         ///
3409         /// No calls to the ManyChannelMonitor will be made during deserialization. It is assumed that
3410         /// you have deserialized ChannelMonitors separately and will add them to your
3411         /// ManyChannelMonitor after deserializing this ChannelManager.
3412         pub monitor: M,
3413
3414         /// The BroadcasterInterface which will be used in the ChannelManager in the future and may be
3415         /// used to broadcast the latest local commitment transactions of channels which must be
3416         /// force-closed during deserialization.
3417         pub tx_broadcaster: T,
3418         /// The Logger for use in the ChannelManager and which may be used to log information during
3419         /// deserialization.
3420         pub logger: Arc<Logger>,
3421         /// Default settings used for new channels. Any existing channels will continue to use the
3422         /// runtime settings which were stored when the ChannelManager was serialized.
3423         pub default_config: UserConfig,
3424
3425         /// A map from channel funding outpoints to ChannelMonitors for those channels (ie
3426         /// value.get_funding_txo() should be the key).
3427         ///
3428         /// If a monitor is inconsistent with the channel state during deserialization the channel will
3429         /// be force-closed using the data in the ChannelMonitor and the channel will be dropped. This
3430         /// is true for missing channels as well. If there is a monitor missing for which we find
3431         /// channel data Err(DecodeError::InvalidValue) will be returned.
3432         ///
3433         /// In such cases the latest local transactions will be sent to the tx_broadcaster included in
3434         /// this struct.
3435         pub channel_monitors: &'a mut HashMap<OutPoint, &'a mut ChannelMonitor<ChanSigner>>,
3436 }
3437
3438 // Implement ReadableArgs for an Arc'd ChannelManager to make it a bit easier to work with the
3439 // SipmleArcChannelManager type:
3440 impl<'a, ChanSigner: ChannelKeys + Readable, M: Deref, T: Deref, K: Deref, F: Deref>
3441         ReadableArgs<ChannelManagerReadArgs<'a, ChanSigner, M, T, K, F>> for (Sha256dHash, Arc<ChannelManager<ChanSigner, M, T, K, F>>)
3442         where M::Target: ManyChannelMonitor<ChanSigner>,
3443         T::Target: BroadcasterInterface,
3444         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
3445         F::Target: FeeEstimator,
3446 {
3447         fn read<R: ::std::io::Read>(reader: &mut R, args: ChannelManagerReadArgs<'a, ChanSigner, M, T, K, F>) -> Result<Self, DecodeError> {
3448                 let (blockhash, chan_manager) = <(Sha256dHash, ChannelManager<ChanSigner, M, T, K, F>)>::read(reader, args)?;
3449                 Ok((blockhash, Arc::new(chan_manager)))
3450         }
3451 }
3452
3453 impl<'a, ChanSigner: ChannelKeys + Readable, M: Deref, T: Deref, K: Deref, F: Deref>
3454         ReadableArgs<ChannelManagerReadArgs<'a, ChanSigner, M, T, K, F>> for (Sha256dHash, ChannelManager<ChanSigner, M, T, K, F>)
3455         where M::Target: ManyChannelMonitor<ChanSigner>,
3456         T::Target: BroadcasterInterface,
3457         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
3458         F::Target: FeeEstimator,
3459 {
3460         fn read<R: ::std::io::Read>(reader: &mut R, args: ChannelManagerReadArgs<'a, ChanSigner, M, T, K, F>) -> Result<Self, DecodeError> {
3461                 let _ver: u8 = Readable::read(reader)?;
3462                 let min_ver: u8 = Readable::read(reader)?;
3463                 if min_ver > SERIALIZATION_VERSION {
3464                         return Err(DecodeError::UnknownVersion);
3465                 }
3466
3467                 let genesis_hash: Sha256dHash = Readable::read(reader)?;
3468                 let latest_block_height: u32 = Readable::read(reader)?;
3469                 let last_block_hash: Sha256dHash = Readable::read(reader)?;
3470
3471                 let mut failed_htlcs = Vec::new();
3472
3473                 let channel_count: u64 = Readable::read(reader)?;
3474                 let mut funding_txo_set = HashSet::with_capacity(cmp::min(channel_count as usize, 128));
3475                 let mut by_id = HashMap::with_capacity(cmp::min(channel_count as usize, 128));
3476                 let mut short_to_id = HashMap::with_capacity(cmp::min(channel_count as usize, 128));
3477                 for _ in 0..channel_count {
3478                         let mut channel: Channel<ChanSigner> = ReadableArgs::read(reader, args.logger.clone())?;
3479                         if channel.last_block_connected != Default::default() && channel.last_block_connected != last_block_hash {
3480                                 return Err(DecodeError::InvalidValue);
3481                         }
3482
3483                         let funding_txo = channel.get_funding_txo().ok_or(DecodeError::InvalidValue)?;
3484                         funding_txo_set.insert(funding_txo.clone());
3485                         if let Some(ref mut monitor) = args.channel_monitors.get_mut(&funding_txo) {
3486                                 if channel.get_cur_local_commitment_transaction_number() < monitor.get_cur_local_commitment_number() ||
3487                                                 channel.get_revoked_remote_commitment_transaction_number() < monitor.get_min_seen_secret() ||
3488                                                 channel.get_cur_remote_commitment_transaction_number() < monitor.get_cur_remote_commitment_number() ||
3489                                                 channel.get_latest_monitor_update_id() > monitor.get_latest_update_id() {
3490                                         // If the channel is ahead of the monitor, return InvalidValue:
3491                                         return Err(DecodeError::InvalidValue);
3492                                 } else if channel.get_cur_local_commitment_transaction_number() > monitor.get_cur_local_commitment_number() ||
3493                                                 channel.get_revoked_remote_commitment_transaction_number() > monitor.get_min_seen_secret() ||
3494                                                 channel.get_cur_remote_commitment_transaction_number() > monitor.get_cur_remote_commitment_number() ||
3495                                                 channel.get_latest_monitor_update_id() < monitor.get_latest_update_id() {
3496                                         // But if the channel is behind of the monitor, close the channel:
3497                                         let (_, _, mut new_failed_htlcs) = channel.force_shutdown(true);
3498                                         failed_htlcs.append(&mut new_failed_htlcs);
3499                                         monitor.broadcast_latest_local_commitment_txn(&args.tx_broadcaster);
3500                                 } else {
3501                                         if let Some(short_channel_id) = channel.get_short_channel_id() {
3502                                                 short_to_id.insert(short_channel_id, channel.channel_id());
3503                                         }
3504                                         by_id.insert(channel.channel_id(), channel);
3505                                 }
3506                         } else {
3507                                 return Err(DecodeError::InvalidValue);
3508                         }
3509                 }
3510
3511                 for (ref funding_txo, ref mut monitor) in args.channel_monitors.iter_mut() {
3512                         if !funding_txo_set.contains(funding_txo) {
3513                                 monitor.broadcast_latest_local_commitment_txn(&args.tx_broadcaster);
3514                         }
3515                 }
3516
3517                 let forward_htlcs_count: u64 = Readable::read(reader)?;
3518                 let mut forward_htlcs = HashMap::with_capacity(cmp::min(forward_htlcs_count as usize, 128));
3519                 for _ in 0..forward_htlcs_count {
3520                         let short_channel_id = Readable::read(reader)?;
3521                         let pending_forwards_count: u64 = Readable::read(reader)?;
3522                         let mut pending_forwards = Vec::with_capacity(cmp::min(pending_forwards_count as usize, 128));
3523                         for _ in 0..pending_forwards_count {
3524                                 pending_forwards.push(Readable::read(reader)?);
3525                         }
3526                         forward_htlcs.insert(short_channel_id, pending_forwards);
3527                 }
3528
3529                 let claimable_htlcs_count: u64 = Readable::read(reader)?;
3530                 let mut claimable_htlcs = HashMap::with_capacity(cmp::min(claimable_htlcs_count as usize, 128));
3531                 for _ in 0..claimable_htlcs_count {
3532                         let payment_hash = Readable::read(reader)?;
3533                         let previous_hops_len: u64 = Readable::read(reader)?;
3534                         let mut previous_hops = Vec::with_capacity(cmp::min(previous_hops_len as usize, 2));
3535                         for _ in 0..previous_hops_len {
3536                                 previous_hops.push(Readable::read(reader)?);
3537                         }
3538                         claimable_htlcs.insert(payment_hash, previous_hops);
3539                 }
3540
3541                 let peer_count: u64 = Readable::read(reader)?;
3542                 let mut per_peer_state = HashMap::with_capacity(cmp::min(peer_count as usize, 128));
3543                 for _ in 0..peer_count {
3544                         let peer_pubkey = Readable::read(reader)?;
3545                         let peer_state = PeerState {
3546                                 latest_features: Readable::read(reader)?,
3547                         };
3548                         per_peer_state.insert(peer_pubkey, Mutex::new(peer_state));
3549                 }
3550
3551                 let last_node_announcement_serial: u32 = Readable::read(reader)?;
3552
3553                 let channel_manager = ChannelManager {
3554                         genesis_hash,
3555                         fee_estimator: args.fee_estimator,
3556                         monitor: args.monitor,
3557                         tx_broadcaster: args.tx_broadcaster,
3558
3559                         latest_block_height: AtomicUsize::new(latest_block_height as usize),
3560                         last_block_hash: Mutex::new(last_block_hash),
3561                         secp_ctx: Secp256k1::new(),
3562
3563                         channel_state: Mutex::new(ChannelHolder {
3564                                 by_id,
3565                                 short_to_id,
3566                                 forward_htlcs,
3567                                 claimable_htlcs,
3568                                 pending_msg_events: Vec::new(),
3569                         }),
3570                         our_network_key: args.keys_manager.get_node_secret(),
3571
3572                         last_node_announcement_serial: AtomicUsize::new(last_node_announcement_serial as usize),
3573
3574                         per_peer_state: RwLock::new(per_peer_state),
3575
3576                         pending_events: Mutex::new(Vec::new()),
3577                         total_consistency_lock: RwLock::new(()),
3578                         keys_manager: args.keys_manager,
3579                         logger: args.logger,
3580                         default_configuration: args.default_config,
3581                 };
3582
3583                 for htlc_source in failed_htlcs.drain(..) {
3584                         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() });
3585                 }
3586
3587                 //TODO: Broadcast channel update for closed channels, but only after we've made a
3588                 //connection or two.
3589
3590                 Ok((last_block_hash.clone(), channel_manager))
3591         }
3592 }