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