b5b8d890b787c39d654941fdaf4e7cf3d436309b
[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 routing::router::get_route 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 use bitcoin::hash_types::BlockHash;
23
24 use bitcoin::secp256k1::key::{SecretKey,PublicKey};
25 use bitcoin::secp256k1::Secp256k1;
26 use bitcoin::secp256k1::ecdh::SharedSecret;
27 use bitcoin::secp256k1;
28
29 use chain::chaininterface::{BroadcasterInterface,ChainListener,FeeEstimator};
30 use chain::transaction::OutPoint;
31 use ln::channel::{Channel, ChannelError};
32 use ln::channelmonitor::{ChannelMonitor, ChannelMonitorUpdate, ChannelMonitorUpdateErr, ManyChannelMonitor, HTLC_FAIL_BACK_BUFFER, CLTV_CLAIM_BUFFER, LATENCY_GRACE_PERIOD_BLOCKS, ANTI_REORG_DELAY};
33 use ln::features::{InitFeatures, NodeFeatures};
34 use routing::router::{Route, RouteHop};
35 use ln::msgs;
36 use ln::onion_utils;
37 use ln::msgs::{ChannelMessageHandler, DecodeError, LightningError};
38 use chain::keysinterface::{ChannelKeys, KeysInterface, KeysManager, InMemoryChannelKeys};
39 use util::config::UserConfig;
40 use util::{byte_utils, events};
41 use util::ser::{Readable, ReadableArgs, MaybeReadable, Writeable, Writer};
42 use util::chacha20::{ChaCha20, ChaChaReader};
43 use util::logger::Logger;
44 use util::errors::APIError;
45
46 use std::{cmp, mem};
47 use std::collections::{HashMap, hash_map, HashSet};
48 use std::io::{Cursor, Read};
49 use std::sync::{Arc, Mutex, MutexGuard, RwLock};
50 use std::sync::atomic::{AtomicUsize, Ordering};
51 use std::time::Duration;
52 use std::marker::{Sync, Send};
53 use std::ops::Deref;
54
55 // We hold various information about HTLC relay in the HTLC objects in Channel itself:
56 //
57 // Upon receipt of an HTLC from a peer, we'll give it a PendingHTLCStatus indicating if it should
58 // forward the HTLC with information it will give back to us when it does so, or if it should Fail
59 // the HTLC with the relevant message for the Channel to handle giving to the remote peer.
60 //
61 // Once said HTLC is committed in the Channel, if the PendingHTLCStatus indicated Forward, the
62 // Channel will return the PendingHTLCInfo back to us, and we will create an HTLCForwardInfo
63 // with it to track where it came from (in case of onwards-forward error), waiting a random delay
64 // before we forward it.
65 //
66 // We will then use HTLCForwardInfo's PendingHTLCInfo to construct an outbound HTLC, with a
67 // relevant HTLCSource::PreviousHopData filled in to indicate where it came from (which we can use
68 // to either fail-backwards or fulfill the HTLC backwards along the relevant path).
69 // Alternatively, we can fill an outbound HTLC with a HTLCSource::OutboundRoute indicating this is
70 // our payment, which we can use to decode errors or inform the user that the payment was sent.
71
72 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
73 enum PendingHTLCRouting {
74         Forward {
75                 onion_packet: msgs::OnionPacket,
76                 short_channel_id: u64, // This should be NonZero<u64> eventually when we bump MSRV
77         },
78         Receive {
79                 payment_data: Option<msgs::FinalOnionHopData>,
80                 incoming_cltv_expiry: u32, // Used to track when we should expire pending HTLCs that go unclaimed
81         },
82 }
83
84 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
85 pub(super) struct PendingHTLCInfo {
86         routing: PendingHTLCRouting,
87         incoming_shared_secret: [u8; 32],
88         payment_hash: PaymentHash,
89         pub(super) amt_to_forward: u64,
90         pub(super) outgoing_cltv_value: u32,
91 }
92
93 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
94 pub(super) enum HTLCFailureMsg {
95         Relay(msgs::UpdateFailHTLC),
96         Malformed(msgs::UpdateFailMalformedHTLC),
97 }
98
99 /// Stores whether we can't forward an HTLC or relevant forwarding info
100 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
101 pub(super) enum PendingHTLCStatus {
102         Forward(PendingHTLCInfo),
103         Fail(HTLCFailureMsg),
104 }
105
106 pub(super) enum HTLCForwardInfo {
107         AddHTLC {
108                 prev_short_channel_id: u64,
109                 prev_htlc_id: u64,
110                 forward_info: PendingHTLCInfo,
111         },
112         FailHTLC {
113                 htlc_id: u64,
114                 err_packet: msgs::OnionErrorPacket,
115         },
116 }
117
118 /// Tracks the inbound corresponding to an outbound HTLC
119 #[derive(Clone, PartialEq)]
120 pub(super) struct HTLCPreviousHopData {
121         short_channel_id: u64,
122         htlc_id: u64,
123         incoming_packet_shared_secret: [u8; 32],
124 }
125
126 struct ClaimableHTLC {
127         prev_hop: HTLCPreviousHopData,
128         value: u64,
129         /// Filled in when the HTLC was received with a payment_secret packet, which contains a
130         /// total_msat (which may differ from value if this is a Multi-Path Payment) and a
131         /// payment_secret which prevents path-probing attacks and can associate different HTLCs which
132         /// are part of the same payment.
133         payment_data: Option<msgs::FinalOnionHopData>,
134         cltv_expiry: u32,
135 }
136
137 /// Tracks the inbound corresponding to an outbound HTLC
138 #[derive(Clone, PartialEq)]
139 pub(super) enum HTLCSource {
140         PreviousHopData(HTLCPreviousHopData),
141         OutboundRoute {
142                 path: Vec<RouteHop>,
143                 session_priv: SecretKey,
144                 /// Technically we can recalculate this from the route, but we cache it here to avoid
145                 /// doing a double-pass on route when we get a failure back
146                 first_hop_htlc_msat: u64,
147         },
148 }
149 #[cfg(test)]
150 impl HTLCSource {
151         pub fn dummy() -> Self {
152                 HTLCSource::OutboundRoute {
153                         path: Vec::new(),
154                         session_priv: SecretKey::from_slice(&[1; 32]).unwrap(),
155                         first_hop_htlc_msat: 0,
156                 }
157         }
158 }
159
160 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
161 pub(super) enum HTLCFailReason {
162         LightningError {
163                 err: msgs::OnionErrorPacket,
164         },
165         Reason {
166                 failure_code: u16,
167                 data: Vec<u8>,
168         }
169 }
170
171 /// payment_hash type, use to cross-lock hop
172 #[derive(Hash, Copy, Clone, PartialEq, Eq, Debug)]
173 pub struct PaymentHash(pub [u8;32]);
174 /// payment_preimage type, use to route payment between hop
175 #[derive(Hash, Copy, Clone, PartialEq, Eq, Debug)]
176 pub struct PaymentPreimage(pub [u8;32]);
177 /// payment_secret type, use to authenticate sender to the receiver and tie MPP HTLCs together
178 #[derive(Hash, Copy, Clone, PartialEq, Eq, Debug)]
179 pub struct PaymentSecret(pub [u8;32]);
180
181 type ShutdownResult = (Option<OutPoint>, ChannelMonitorUpdate, Vec<(HTLCSource, PaymentHash)>);
182
183 /// Error type returned across the channel_state mutex boundary. When an Err is generated for a
184 /// Channel, we generally end up with a ChannelError::Close for which we have to close the channel
185 /// immediately (ie with no further calls on it made). Thus, this step happens inside a
186 /// channel_state lock. We then return the set of things that need to be done outside the lock in
187 /// this struct and call handle_error!() on it.
188
189 struct MsgHandleErrInternal {
190         err: msgs::LightningError,
191         shutdown_finish: Option<(ShutdownResult, Option<msgs::ChannelUpdate>)>,
192 }
193 impl MsgHandleErrInternal {
194         #[inline]
195         fn send_err_msg_no_close(err: &'static str, channel_id: [u8; 32]) -> Self {
196                 Self {
197                         err: LightningError {
198                                 err,
199                                 action: msgs::ErrorAction::SendErrorMessage {
200                                         msg: msgs::ErrorMessage {
201                                                 channel_id,
202                                                 data: err.to_string()
203                                         },
204                                 },
205                         },
206                         shutdown_finish: None,
207                 }
208         }
209         #[inline]
210         fn ignore_no_close(err: &'static str) -> Self {
211                 Self {
212                         err: LightningError {
213                                 err,
214                                 action: msgs::ErrorAction::IgnoreError,
215                         },
216                         shutdown_finish: None,
217                 }
218         }
219         #[inline]
220         fn from_no_close(err: msgs::LightningError) -> Self {
221                 Self { err, shutdown_finish: None }
222         }
223         #[inline]
224         fn from_finish_shutdown(err: &'static str, channel_id: [u8; 32], shutdown_res: ShutdownResult, channel_update: Option<msgs::ChannelUpdate>) -> Self {
225                 Self {
226                         err: LightningError {
227                                 err,
228                                 action: msgs::ErrorAction::SendErrorMessage {
229                                         msg: msgs::ErrorMessage {
230                                                 channel_id,
231                                                 data: err.to_string()
232                                         },
233                                 },
234                         },
235                         shutdown_finish: Some((shutdown_res, channel_update)),
236                 }
237         }
238         #[inline]
239         fn from_chan_no_close(err: ChannelError, channel_id: [u8; 32]) -> Self {
240                 Self {
241                         err: match err {
242                                 ChannelError::Ignore(msg) => LightningError {
243                                         err: msg,
244                                         action: msgs::ErrorAction::IgnoreError,
245                                 },
246                                 ChannelError::Close(msg) => LightningError {
247                                         err: msg,
248                                         action: msgs::ErrorAction::SendErrorMessage {
249                                                 msg: msgs::ErrorMessage {
250                                                         channel_id,
251                                                         data: msg.to_string()
252                                                 },
253                                         },
254                                 },
255                                 ChannelError::CloseDelayBroadcast(msg) => LightningError {
256                                         err: msg,
257                                         action: msgs::ErrorAction::SendErrorMessage {
258                                                 msg: msgs::ErrorMessage {
259                                                         channel_id,
260                                                         data: msg.to_string()
261                                                 },
262                                         },
263                                 },
264                         },
265                         shutdown_finish: None,
266                 }
267         }
268 }
269
270 /// We hold back HTLCs we intend to relay for a random interval greater than this (see
271 /// Event::PendingHTLCsForwardable for the API guidelines indicating how long should be waited).
272 /// This provides some limited amount of privacy. Ideally this would range from somewhere like one
273 /// second to 30 seconds, but people expect lightning to be, you know, kinda fast, sadly.
274 const MIN_HTLC_RELAY_HOLDING_CELL_MILLIS: u64 = 100;
275
276 /// For events which result in both a RevokeAndACK and a CommitmentUpdate, by default they should
277 /// be sent in the order they appear in the return value, however sometimes the order needs to be
278 /// variable at runtime (eg Channel::channel_reestablish needs to re-send messages in the order
279 /// they were originally sent). In those cases, this enum is also returned.
280 #[derive(Clone, PartialEq)]
281 pub(super) enum RAACommitmentOrder {
282         /// Send the CommitmentUpdate messages first
283         CommitmentFirst,
284         /// Send the RevokeAndACK message first
285         RevokeAndACKFirst,
286 }
287
288 // Note this is only exposed in cfg(test):
289 pub(super) struct ChannelHolder<ChanSigner: ChannelKeys> {
290         pub(super) by_id: HashMap<[u8; 32], Channel<ChanSigner>>,
291         pub(super) short_to_id: HashMap<u64, [u8; 32]>,
292         /// short channel id -> forward infos. Key of 0 means payments received
293         /// Note that while this is held in the same mutex as the channels themselves, no consistency
294         /// guarantees are made about the existence of a channel with the short id here, nor the short
295         /// ids in the PendingHTLCInfo!
296         pub(super) forward_htlcs: HashMap<u64, Vec<HTLCForwardInfo>>,
297         /// (payment_hash, payment_secret) -> Vec<HTLCs> for tracking HTLCs that
298         /// were to us and can be failed/claimed by the user
299         /// Note that while this is held in the same mutex as the channels themselves, no consistency
300         /// guarantees are made about the channels given here actually existing anymore by the time you
301         /// go to read them!
302         claimable_htlcs: HashMap<(PaymentHash, Option<PaymentSecret>), Vec<ClaimableHTLC>>,
303         /// Messages to send to peers - pushed to in the same lock that they are generated in (except
304         /// for broadcast messages, where ordering isn't as strict).
305         pub(super) pending_msg_events: Vec<events::MessageSendEvent>,
306 }
307
308 /// State we hold per-peer. In the future we should put channels in here, but for now we only hold
309 /// the latest Init features we heard from the peer.
310 struct PeerState {
311         latest_features: InitFeatures,
312 }
313
314 #[cfg(not(any(target_pointer_width = "32", target_pointer_width = "64")))]
315 const ERR: () = "You need at least 32 bit pointers (well, usize, but we'll assume they're the same) for ChannelManager::latest_block_height";
316
317 /// SimpleArcChannelManager is useful when you need a ChannelManager with a static lifetime, e.g.
318 /// when you're using lightning-net-tokio (since tokio::spawn requires parameters with static
319 /// lifetimes). Other times you can afford a reference, which is more efficient, in which case
320 /// SimpleRefChannelManager is the more appropriate type. Defining these type aliases prevents
321 /// issues such as overly long function definitions. Note that the ChannelManager can take any
322 /// type that implements KeysInterface for its keys manager, but this type alias chooses the
323 /// concrete type of the KeysManager.
324 pub type SimpleArcChannelManager<M, T, F, L> = Arc<ChannelManager<InMemoryChannelKeys, Arc<M>, Arc<T>, Arc<KeysManager>, Arc<F>, Arc<L>>>;
325
326 /// SimpleRefChannelManager is a type alias for a ChannelManager reference, and is the reference
327 /// counterpart to the SimpleArcChannelManager type alias. Use this type by default when you don't
328 /// need a ChannelManager with a static lifetime. You'll need a static lifetime in cases such as
329 /// usage of lightning-net-tokio (since tokio::spawn requires parameters with static lifetimes).
330 /// But if this is not necessary, using a reference is more efficient. Defining these type aliases
331 /// helps with issues such as long function definitions. Note that the ChannelManager can take any
332 /// type that implements KeysInterface for its keys manager, but this type alias chooses the
333 /// concrete type of the KeysManager.
334 pub type SimpleRefChannelManager<'a, 'b, 'c, 'd, 'e, M, T, F, L> = ChannelManager<InMemoryChannelKeys, &'a M, &'b T, &'c KeysManager, &'d F, &'e L>;
335
336 /// Manager which keeps track of a number of channels and sends messages to the appropriate
337 /// channel, also tracking HTLC preimages and forwarding onion packets appropriately.
338 ///
339 /// Implements ChannelMessageHandler, handling the multi-channel parts and passing things through
340 /// to individual Channels.
341 ///
342 /// Implements Writeable to write out all channel state to disk. Implies peer_disconnected() for
343 /// all peers during write/read (though does not modify this instance, only the instance being
344 /// serialized). This will result in any channels which have not yet exchanged funding_created (ie
345 /// called funding_transaction_generated for outbound channels).
346 ///
347 /// Note that you can be a bit lazier about writing out ChannelManager than you can be with
348 /// ChannelMonitors. With ChannelMonitors you MUST write each monitor update out to disk before
349 /// returning from ManyChannelMonitor::add_/update_monitor, with ChannelManagers, writing updates
350 /// happens out-of-band (and will prevent any other ChannelManager operations from occurring during
351 /// the serialization process). If the deserialized version is out-of-date compared to the
352 /// ChannelMonitors passed by reference to read(), those channels will be force-closed based on the
353 /// ChannelMonitor state and no funds will be lost (mod on-chain transaction fees).
354 ///
355 /// Note that the deserializer is only implemented for (Sha256dHash, ChannelManager), which
356 /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
357 /// the "reorg path" (ie call block_disconnected() until you get to a common block and then call
358 /// block_connected() to step towards your best block) upon deserialization before using the
359 /// object!
360 ///
361 /// Note that ChannelManager is responsible for tracking liveness of its channels and generating
362 /// ChannelUpdate messages informing peers that the channel is temporarily disabled. To avoid
363 /// spam due to quick disconnection/reconnection, updates are not sent until the channel has been
364 /// offline for a full minute. In order to track this, you must call
365 /// timer_chan_freshness_every_min roughly once per minute, though it doesn't have to be perfect.
366 ///
367 /// Rather than using a plain ChannelManager, it is preferable to use either a SimpleArcChannelManager
368 /// a SimpleRefChannelManager, for conciseness. See their documentation for more details, but
369 /// essentially you should default to using a SimpleRefChannelManager, and use a
370 /// SimpleArcChannelManager when you require a ChannelManager with a static lifetime, such as when
371 /// you're using lightning-net-tokio.
372 pub struct ChannelManager<ChanSigner: ChannelKeys, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
373         where M::Target: ManyChannelMonitor<ChanSigner>,
374         T::Target: BroadcasterInterface,
375         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
376         F::Target: FeeEstimator,
377                                 L::Target: Logger,
378 {
379         default_configuration: UserConfig,
380         genesis_hash: BlockHash,
381         fee_estimator: F,
382         monitor: M,
383         tx_broadcaster: T,
384
385         #[cfg(test)]
386         pub(super) latest_block_height: AtomicUsize,
387         #[cfg(not(test))]
388         latest_block_height: AtomicUsize,
389         last_block_hash: Mutex<BlockHash>,
390         secp_ctx: Secp256k1<secp256k1::All>,
391
392         #[cfg(test)]
393         pub(super) channel_state: Mutex<ChannelHolder<ChanSigner>>,
394         #[cfg(not(test))]
395         channel_state: Mutex<ChannelHolder<ChanSigner>>,
396         our_network_key: SecretKey,
397
398         /// Used to track the last value sent in a node_announcement "timestamp" field. We ensure this
399         /// value increases strictly since we don't assume access to a time source.
400         last_node_announcement_serial: AtomicUsize,
401
402         /// The bulk of our storage will eventually be here (channels and message queues and the like).
403         /// If we are connected to a peer we always at least have an entry here, even if no channels
404         /// are currently open with that peer.
405         /// Because adding or removing an entry is rare, we usually take an outer read lock and then
406         /// operate on the inner value freely. Sadly, this prevents parallel operation when opening a
407         /// new channel.
408         per_peer_state: RwLock<HashMap<PublicKey, Mutex<PeerState>>>,
409
410         pending_events: Mutex<Vec<events::Event>>,
411         /// Used when we have to take a BIG lock to make sure everything is self-consistent.
412         /// Essentially just when we're serializing ourselves out.
413         /// Taken first everywhere where we are making changes before any other locks.
414         total_consistency_lock: RwLock<()>,
415
416         keys_manager: K,
417
418         logger: L,
419 }
420
421 /// The amount of time we require our counterparty wait to claim their money (ie time between when
422 /// we, or our watchtower, must check for them having broadcast a theft transaction).
423 pub(crate) const BREAKDOWN_TIMEOUT: u16 = 6 * 24;
424 /// The amount of time we're willing to wait to claim money back to us
425 pub(crate) const MAX_LOCAL_BREAKDOWN_TIMEOUT: u16 = 6 * 24 * 7;
426
427 /// The minimum number of blocks between an inbound HTLC's CLTV and the corresponding outbound
428 /// HTLC's CLTV. This should always be a few blocks greater than channelmonitor::CLTV_CLAIM_BUFFER,
429 /// ie the node we forwarded the payment on to should always have enough room to reliably time out
430 /// the HTLC via a full update_fail_htlc/commitment_signed dance before we hit the
431 /// CLTV_CLAIM_BUFFER point (we static assert that it's at least 3 blocks more).
432 const CLTV_EXPIRY_DELTA: u16 = 6 * 12; //TODO?
433 pub(super) const CLTV_FAR_FAR_AWAY: u32 = 6 * 24 * 7; //TODO?
434
435 // Check that our CLTV_EXPIRY is at least CLTV_CLAIM_BUFFER + ANTI_REORG_DELAY + LATENCY_GRACE_PERIOD_BLOCKS,
436 // ie that if the next-hop peer fails the HTLC within
437 // LATENCY_GRACE_PERIOD_BLOCKS then we'll still have CLTV_CLAIM_BUFFER left to timeout it onchain,
438 // then waiting ANTI_REORG_DELAY to be reorg-safe on the outbound HLTC and
439 // failing the corresponding htlc backward, and us now seeing the last block of ANTI_REORG_DELAY before
440 // LATENCY_GRACE_PERIOD_BLOCKS.
441 #[deny(const_err)]
442 #[allow(dead_code)]
443 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;
444
445 // Check for ability of an attacker to make us fail on-chain by delaying inbound claim. See
446 // ChannelMontior::would_broadcast_at_height for a description of why this is needed.
447 #[deny(const_err)]
448 #[allow(dead_code)]
449 const CHECK_CLTV_EXPIRY_SANITY_2: u32 = CLTV_EXPIRY_DELTA as u32 - LATENCY_GRACE_PERIOD_BLOCKS - 2*CLTV_CLAIM_BUFFER;
450
451 /// Details of a channel, as returned by ChannelManager::list_channels and ChannelManager::list_usable_channels
452 pub struct ChannelDetails {
453         /// The channel's ID (prior to funding transaction generation, this is a random 32 bytes,
454         /// thereafter this is the txid of the funding transaction xor the funding transaction output).
455         /// Note that this means this value is *not* persistent - it can change once during the
456         /// lifetime of the channel.
457         pub channel_id: [u8; 32],
458         /// The position of the funding transaction in the chain. None if the funding transaction has
459         /// not yet been confirmed and the channel fully opened.
460         pub short_channel_id: Option<u64>,
461         /// The node_id of our counterparty
462         pub remote_network_id: PublicKey,
463         /// The Features the channel counterparty provided upon last connection.
464         /// Useful for routing as it is the most up-to-date copy of the counterparty's features and
465         /// many routing-relevant features are present in the init context.
466         pub counterparty_features: InitFeatures,
467         /// The value, in satoshis, of this channel as appears in the funding output
468         pub channel_value_satoshis: u64,
469         /// The user_id passed in to create_channel, or 0 if the channel was inbound.
470         pub user_id: u64,
471         /// The available outbound capacity for sending HTLCs to the remote peer. This does not include
472         /// any pending HTLCs which are not yet fully resolved (and, thus, who's balance is not
473         /// available for inclusion in new outbound HTLCs). This further does not include any pending
474         /// outgoing HTLCs which are awaiting some other resolution to be sent.
475         pub outbound_capacity_msat: u64,
476         /// The available inbound capacity for the remote peer to send HTLCs to us. This does not
477         /// include any pending HTLCs which are not yet fully resolved (and, thus, who's balance is not
478         /// available for inclusion in new inbound HTLCs).
479         /// Note that there are some corner cases not fully handled here, so the actual available
480         /// inbound capacity may be slightly higher than this.
481         pub inbound_capacity_msat: u64,
482         /// True if the channel is (a) confirmed and funding_locked messages have been exchanged, (b)
483         /// the peer is connected, and (c) no monitor update failure is pending resolution.
484         pub is_live: bool,
485 }
486
487 /// If a payment fails to send, it can be in one of several states. This enum is returned as the
488 /// Err() type describing which state the payment is in, see the description of individual enum
489 /// states for more.
490 #[derive(Debug)]
491 pub enum PaymentSendFailure {
492         /// A parameter which was passed to send_payment was invalid, preventing us from attempting to
493         /// send the payment at all. No channel state has been changed or messages sent to peers, and
494         /// once you've changed the parameter at error, you can freely retry the payment in full.
495         ParameterError(APIError),
496         /// A parameter in a single path which was passed to send_payment was invalid, preventing us
497         /// from attempting to send the payment at all. No channel state has been changed or messages
498         /// sent to peers, and once you've changed the parameter at error, you can freely retry the
499         /// payment in full.
500         ///
501         /// The results here are ordered the same as the paths in the route object which was passed to
502         /// send_payment.
503         PathParameterError(Vec<Result<(), APIError>>),
504         /// All paths which were attempted failed to send, with no channel state change taking place.
505         /// You can freely retry the payment in full (though you probably want to do so over different
506         /// paths than the ones selected).
507         AllFailedRetrySafe(Vec<APIError>),
508         /// Some paths which were attempted failed to send, though possibly not all. At least some
509         /// paths have irrevocably committed to the HTLC and retrying the payment in full would result
510         /// in over-/re-payment.
511         ///
512         /// The results here are ordered the same as the paths in the route object which was passed to
513         /// send_payment, and any Errs which are not APIError::MonitorUpdateFailed can be safely
514         /// retried (though there is currently no API with which to do so).
515         ///
516         /// Any entries which contain Err(APIError::MonitorUpdateFailed) or Ok(()) MUST NOT be retried
517         /// as they will result in over-/re-payment. These HTLCs all either successfully sent (in the
518         /// case of Ok(())) or will send once channel_monitor_updated is called on the next-hop channel
519         /// with the latest update_id.
520         PartialFailure(Vec<Result<(), APIError>>),
521 }
522
523 macro_rules! handle_error {
524         ($self: ident, $internal: expr, $their_node_id: expr) => {
525                 match $internal {
526                         Ok(msg) => Ok(msg),
527                         Err(MsgHandleErrInternal { err, shutdown_finish }) => {
528                                 #[cfg(debug_assertions)]
529                                 {
530                                         // In testing, ensure there are no deadlocks where the lock is already held upon
531                                         // entering the macro.
532                                         assert!($self.channel_state.try_lock().is_ok());
533                                 }
534
535                                 let mut msg_events = Vec::with_capacity(2);
536
537                                 if let Some((shutdown_res, update_option)) = shutdown_finish {
538                                         $self.finish_force_close_channel(shutdown_res);
539                                         if let Some(update) = update_option {
540                                                 msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
541                                                         msg: update
542                                                 });
543                                         }
544                                 }
545
546                                 log_error!($self.logger, "{}", err.err);
547                                 if let msgs::ErrorAction::IgnoreError = err.action {
548                                 } else {
549                                         msg_events.push(events::MessageSendEvent::HandleError {
550                                                 node_id: $their_node_id,
551                                                 action: err.action.clone()
552                                         });
553                                 }
554
555                                 if !msg_events.is_empty() {
556                                         $self.channel_state.lock().unwrap().pending_msg_events.append(&mut msg_events);
557                                 }
558
559                                 // Return error in case higher-API need one
560                                 Err(err)
561                         },
562                 }
563         }
564 }
565
566 macro_rules! break_chan_entry {
567         ($self: ident, $res: expr, $channel_state: expr, $entry: expr) => {
568                 match $res {
569                         Ok(res) => res,
570                         Err(ChannelError::Ignore(msg)) => {
571                                 break Err(MsgHandleErrInternal::from_chan_no_close(ChannelError::Ignore(msg), $entry.key().clone()))
572                         },
573                         Err(ChannelError::Close(msg)) => {
574                                 log_trace!($self.logger, "Closing channel {} due to Close-required error: {}", log_bytes!($entry.key()[..]), msg);
575                                 let (channel_id, mut chan) = $entry.remove_entry();
576                                 if let Some(short_id) = chan.get_short_channel_id() {
577                                         $channel_state.short_to_id.remove(&short_id);
578                                 }
579                                 break Err(MsgHandleErrInternal::from_finish_shutdown(msg, channel_id, chan.force_shutdown(true), $self.get_channel_update(&chan).ok()))
580                         },
581                         Err(ChannelError::CloseDelayBroadcast(_)) => { panic!("Wait is only generated on receipt of channel_reestablish, which is handled by try_chan_entry, we don't bother to support it here"); }
582                 }
583         }
584 }
585
586 macro_rules! try_chan_entry {
587         ($self: ident, $res: expr, $channel_state: expr, $entry: expr) => {
588                 match $res {
589                         Ok(res) => res,
590                         Err(ChannelError::Ignore(msg)) => {
591                                 return Err(MsgHandleErrInternal::from_chan_no_close(ChannelError::Ignore(msg), $entry.key().clone()))
592                         },
593                         Err(ChannelError::Close(msg)) => {
594                                 log_trace!($self.logger, "Closing channel {} due to Close-required error: {}", log_bytes!($entry.key()[..]), msg);
595                                 let (channel_id, mut chan) = $entry.remove_entry();
596                                 if let Some(short_id) = chan.get_short_channel_id() {
597                                         $channel_state.short_to_id.remove(&short_id);
598                                 }
599                                 return Err(MsgHandleErrInternal::from_finish_shutdown(msg, channel_id, chan.force_shutdown(true), $self.get_channel_update(&chan).ok()))
600                         },
601                         Err(ChannelError::CloseDelayBroadcast(msg)) => {
602                                 log_error!($self.logger, "Channel {} need to be shutdown but closing transactions not broadcast due to {}", log_bytes!($entry.key()[..]), msg);
603                                 let (channel_id, mut chan) = $entry.remove_entry();
604                                 if let Some(short_id) = chan.get_short_channel_id() {
605                                         $channel_state.short_to_id.remove(&short_id);
606                                 }
607                                 let shutdown_res = chan.force_shutdown(false);
608                                 return Err(MsgHandleErrInternal::from_finish_shutdown(msg, channel_id, shutdown_res, $self.get_channel_update(&chan).ok()))
609                         }
610                 }
611         }
612 }
613
614 macro_rules! handle_monitor_err {
615         ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $resend_raa: expr, $resend_commitment: expr) => {
616                 handle_monitor_err!($self, $err, $channel_state, $entry, $action_type, $resend_raa, $resend_commitment, Vec::new(), Vec::new())
617         };
618         ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $resend_raa: expr, $resend_commitment: expr, $failed_forwards: expr, $failed_fails: expr) => {
619                 match $err {
620                         ChannelMonitorUpdateErr::PermanentFailure => {
621                                 log_error!($self.logger, "Closing channel {} due to monitor update PermanentFailure", log_bytes!($entry.key()[..]));
622                                 let (channel_id, mut chan) = $entry.remove_entry();
623                                 if let Some(short_id) = chan.get_short_channel_id() {
624                                         $channel_state.short_to_id.remove(&short_id);
625                                 }
626                                 // TODO: $failed_fails is dropped here, which will cause other channels to hit the
627                                 // chain in a confused state! We need to move them into the ChannelMonitor which
628                                 // will be responsible for failing backwards once things confirm on-chain.
629                                 // It's ok that we drop $failed_forwards here - at this point we'd rather they
630                                 // broadcast HTLC-Timeout and pay the associated fees to get their funds back than
631                                 // us bother trying to claim it just to forward on to another peer. If we're
632                                 // splitting hairs we'd prefer to claim payments that were to us, but we haven't
633                                 // given up the preimage yet, so might as well just wait until the payment is
634                                 // retried, avoiding the on-chain fees.
635                                 let res: Result<(), _> = Err(MsgHandleErrInternal::from_finish_shutdown("ChannelMonitor storage failure", channel_id, chan.force_shutdown(true), $self.get_channel_update(&chan).ok()));
636                                 res
637                         },
638                         ChannelMonitorUpdateErr::TemporaryFailure => {
639                                 log_info!($self.logger, "Disabling channel {} due to monitor update TemporaryFailure. On restore will send {} and process {} forwards and {} fails",
640                                                 log_bytes!($entry.key()[..]),
641                                                 if $resend_commitment && $resend_raa {
642                                                                 match $action_type {
643                                                                         RAACommitmentOrder::CommitmentFirst => { "commitment then RAA" },
644                                                                         RAACommitmentOrder::RevokeAndACKFirst => { "RAA then commitment" },
645                                                                 }
646                                                         } else if $resend_commitment { "commitment" }
647                                                         else if $resend_raa { "RAA" }
648                                                         else { "nothing" },
649                                                 (&$failed_forwards as &Vec<(PendingHTLCInfo, u64)>).len(),
650                                                 (&$failed_fails as &Vec<(HTLCSource, PaymentHash, HTLCFailReason)>).len());
651                                 if !$resend_commitment {
652                                         debug_assert!($action_type == RAACommitmentOrder::RevokeAndACKFirst || !$resend_raa);
653                                 }
654                                 if !$resend_raa {
655                                         debug_assert!($action_type == RAACommitmentOrder::CommitmentFirst || !$resend_commitment);
656                                 }
657                                 $entry.get_mut().monitor_update_failed($resend_raa, $resend_commitment, $failed_forwards, $failed_fails);
658                                 Err(MsgHandleErrInternal::from_chan_no_close(ChannelError::Ignore("Failed to update ChannelMonitor"), *$entry.key()))
659                         },
660                 }
661         }
662 }
663
664 macro_rules! return_monitor_err {
665         ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $resend_raa: expr, $resend_commitment: expr) => {
666                 return handle_monitor_err!($self, $err, $channel_state, $entry, $action_type, $resend_raa, $resend_commitment);
667         };
668         ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $resend_raa: expr, $resend_commitment: expr, $failed_forwards: expr, $failed_fails: expr) => {
669                 return handle_monitor_err!($self, $err, $channel_state, $entry, $action_type, $resend_raa, $resend_commitment, $failed_forwards, $failed_fails);
670         }
671 }
672
673 // Does not break in case of TemporaryFailure!
674 macro_rules! maybe_break_monitor_err {
675         ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $resend_raa: expr, $resend_commitment: expr) => {
676                 match (handle_monitor_err!($self, $err, $channel_state, $entry, $action_type, $resend_raa, $resend_commitment), $err) {
677                         (e, ChannelMonitorUpdateErr::PermanentFailure) => {
678                                 break e;
679                         },
680                         (_, ChannelMonitorUpdateErr::TemporaryFailure) => { },
681                 }
682         }
683 }
684
685 impl<ChanSigner: ChannelKeys, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelManager<ChanSigner, M, T, K, F, L>
686         where M::Target: ManyChannelMonitor<ChanSigner>,
687         T::Target: BroadcasterInterface,
688         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
689         F::Target: FeeEstimator,
690         L::Target: Logger,
691 {
692         /// Constructs a new ChannelManager to hold several channels and route between them.
693         ///
694         /// This is the main "logic hub" for all channel-related actions, and implements
695         /// ChannelMessageHandler.
696         ///
697         /// Non-proportional fees are fixed according to our risk using the provided fee estimator.
698         ///
699         /// panics if channel_value_satoshis is >= `MAX_FUNDING_SATOSHIS`!
700         ///
701         /// Users must provide the current blockchain height from which to track onchain channel
702         /// funding outpoints and send payments with reliable timelocks.
703         ///
704         /// Users need to notify the new ChannelManager when a new block is connected or
705         /// disconnected using its `block_connected` and `block_disconnected` methods.
706         /// However, rather than calling these methods directly, the user should register
707         /// the ChannelManager as a listener to the BlockNotifier and call the BlockNotifier's
708         /// `block_(dis)connected` methods, which will notify all registered listeners in one
709         /// go.
710         pub fn new(network: Network, fee_est: F, monitor: M, tx_broadcaster: T, logger: L, keys_manager: K, config: UserConfig, current_blockchain_height: usize) -> Result<ChannelManager<ChanSigner, M, T, K, F, L>, secp256k1::Error> {
711                 let secp_ctx = Secp256k1::new();
712
713                 let res = ChannelManager {
714                         default_configuration: config.clone(),
715                         genesis_hash: genesis_block(network).header.bitcoin_hash(),
716                         //genesis_hash: Sha256dHash::from_hex("0f9188f13cb7b2c71f2a335e3a4fc328bf5beb436012afca590b1a11466e2206").unwrap(),
717                         fee_estimator: fee_est,
718                         monitor,
719                         tx_broadcaster,
720
721                         latest_block_height: AtomicUsize::new(current_blockchain_height),
722                         last_block_hash: Mutex::new(Default::default()),
723                         secp_ctx,
724
725                         channel_state: Mutex::new(ChannelHolder{
726                                 by_id: HashMap::new(),
727                                 short_to_id: HashMap::new(),
728                                 forward_htlcs: HashMap::new(),
729                                 claimable_htlcs: HashMap::new(),
730                                 pending_msg_events: Vec::new(),
731                         }),
732                         our_network_key: keys_manager.get_node_secret(),
733
734                         last_node_announcement_serial: AtomicUsize::new(0),
735
736                         per_peer_state: RwLock::new(HashMap::new()),
737
738                         pending_events: Mutex::new(Vec::new()),
739                         total_consistency_lock: RwLock::new(()),
740
741                         keys_manager,
742
743                         logger,
744                 };
745
746                 Ok(res)
747         }
748
749         /// Creates a new outbound channel to the given remote node and with the given value.
750         ///
751         /// user_id will be provided back as user_channel_id in FundingGenerationReady and
752         /// FundingBroadcastSafe events to allow tracking of which events correspond with which
753         /// create_channel call. Note that user_channel_id defaults to 0 for inbound channels, so you
754         /// may wish to avoid using 0 for user_id here.
755         ///
756         /// If successful, will generate a SendOpenChannel message event, so you should probably poll
757         /// PeerManager::process_events afterwards.
758         ///
759         /// Raises APIError::APIMisuseError when channel_value_satoshis > 2**24 or push_msat is
760         /// greater than channel_value_satoshis * 1k or channel_value_satoshis is < 1000.
761         pub fn create_channel(&self, their_network_key: PublicKey, channel_value_satoshis: u64, push_msat: u64, user_id: u64, override_config: Option<UserConfig>) -> Result<(), APIError> {
762                 if channel_value_satoshis < 1000 {
763                         return Err(APIError::APIMisuseError { err: "channel_value must be at least 1000 satoshis" });
764                 }
765
766                 let config = if override_config.is_some() { override_config.as_ref().unwrap() } else { &self.default_configuration };
767                 let channel = Channel::new_outbound(&self.fee_estimator, &self.keys_manager, their_network_key, channel_value_satoshis, push_msat, user_id, config)?;
768                 let res = channel.get_open_channel(self.genesis_hash.clone(), &self.fee_estimator);
769
770                 let _ = self.total_consistency_lock.read().unwrap();
771                 let mut channel_state = self.channel_state.lock().unwrap();
772                 match channel_state.by_id.entry(channel.channel_id()) {
773                         hash_map::Entry::Occupied(_) => {
774                                 if cfg!(feature = "fuzztarget") {
775                                         return Err(APIError::APIMisuseError { err: "Fuzzy bad RNG" });
776                                 } else {
777                                         panic!("RNG is bad???");
778                                 }
779                         },
780                         hash_map::Entry::Vacant(entry) => { entry.insert(channel); }
781                 }
782                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendOpenChannel {
783                         node_id: their_network_key,
784                         msg: res,
785                 });
786                 Ok(())
787         }
788
789         fn list_channels_with_filter<Fn: FnMut(&(&[u8; 32], &Channel<ChanSigner>)) -> bool>(&self, f: Fn) -> Vec<ChannelDetails> {
790                 let mut res = Vec::new();
791                 {
792                         let channel_state = self.channel_state.lock().unwrap();
793                         res.reserve(channel_state.by_id.len());
794                         for (channel_id, channel) in channel_state.by_id.iter().filter(f) {
795                                 let (inbound_capacity_msat, outbound_capacity_msat) = channel.get_inbound_outbound_available_balance_msat();
796                                 res.push(ChannelDetails {
797                                         channel_id: (*channel_id).clone(),
798                                         short_channel_id: channel.get_short_channel_id(),
799                                         remote_network_id: channel.get_their_node_id(),
800                                         counterparty_features: InitFeatures::empty(),
801                                         channel_value_satoshis: channel.get_value_satoshis(),
802                                         inbound_capacity_msat,
803                                         outbound_capacity_msat,
804                                         user_id: channel.get_user_id(),
805                                         is_live: channel.is_live(),
806                                 });
807                         }
808                 }
809                 let per_peer_state = self.per_peer_state.read().unwrap();
810                 for chan in res.iter_mut() {
811                         if let Some(peer_state) = per_peer_state.get(&chan.remote_network_id) {
812                                 chan.counterparty_features = peer_state.lock().unwrap().latest_features.clone();
813                         }
814                 }
815                 res
816         }
817
818         /// Gets the list of open channels, in random order. See ChannelDetail field documentation for
819         /// more information.
820         pub fn list_channels(&self) -> Vec<ChannelDetails> {
821                 self.list_channels_with_filter(|_| true)
822         }
823
824         /// Gets the list of usable channels, in random order. Useful as an argument to
825         /// get_route to ensure non-announced channels are used.
826         ///
827         /// These are guaranteed to have their is_live value set to true, see the documentation for
828         /// ChannelDetails::is_live for more info on exactly what the criteria are.
829         pub fn list_usable_channels(&self) -> Vec<ChannelDetails> {
830                 // Note we use is_live here instead of usable which leads to somewhat confused
831                 // internal/external nomenclature, but that's ok cause that's probably what the user
832                 // really wanted anyway.
833                 self.list_channels_with_filter(|&(_, ref channel)| channel.is_live())
834         }
835
836         /// Begins the process of closing a channel. After this call (plus some timeout), no new HTLCs
837         /// will be accepted on the given channel, and after additional timeout/the closing of all
838         /// pending HTLCs, the channel will be closed on chain.
839         ///
840         /// May generate a SendShutdown message event on success, which should be relayed.
841         pub fn close_channel(&self, channel_id: &[u8; 32]) -> Result<(), APIError> {
842                 let _ = self.total_consistency_lock.read().unwrap();
843
844                 let (mut failed_htlcs, chan_option) = {
845                         let mut channel_state_lock = self.channel_state.lock().unwrap();
846                         let channel_state = &mut *channel_state_lock;
847                         match channel_state.by_id.entry(channel_id.clone()) {
848                                 hash_map::Entry::Occupied(mut chan_entry) => {
849                                         let (shutdown_msg, failed_htlcs) = chan_entry.get_mut().get_shutdown()?;
850                                         channel_state.pending_msg_events.push(events::MessageSendEvent::SendShutdown {
851                                                 node_id: chan_entry.get().get_their_node_id(),
852                                                 msg: shutdown_msg
853                                         });
854                                         if chan_entry.get().is_shutdown() {
855                                                 if let Some(short_id) = chan_entry.get().get_short_channel_id() {
856                                                         channel_state.short_to_id.remove(&short_id);
857                                                 }
858                                                 (failed_htlcs, Some(chan_entry.remove_entry().1))
859                                         } else { (failed_htlcs, None) }
860                                 },
861                                 hash_map::Entry::Vacant(_) => return Err(APIError::ChannelUnavailable{err: "No such channel"})
862                         }
863                 };
864                 for htlc_source in failed_htlcs.drain(..) {
865                         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() });
866                 }
867                 let chan_update = if let Some(chan) = chan_option {
868                         if let Ok(update) = self.get_channel_update(&chan) {
869                                 Some(update)
870                         } else { None }
871                 } else { None };
872
873                 if let Some(update) = chan_update {
874                         let mut channel_state = self.channel_state.lock().unwrap();
875                         channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
876                                 msg: update
877                         });
878                 }
879
880                 Ok(())
881         }
882
883         #[inline]
884         fn finish_force_close_channel(&self, shutdown_res: ShutdownResult) {
885                 let (funding_txo_option, monitor_update, mut failed_htlcs) = shutdown_res;
886                 log_trace!(self.logger, "Finishing force-closure of channel {} HTLCs to fail", failed_htlcs.len());
887                 for htlc_source in failed_htlcs.drain(..) {
888                         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() });
889                 }
890                 if let Some(funding_txo) = funding_txo_option {
891                         // There isn't anything we can do if we get an update failure - we're already
892                         // force-closing. The monitor update on the required in-memory copy should broadcast
893                         // the latest local state, which is the best we can do anyway. Thus, it is safe to
894                         // ignore the result here.
895                         let _ = self.monitor.update_monitor(funding_txo, monitor_update);
896                 }
897         }
898
899         /// Force closes a channel, immediately broadcasting the latest local commitment transaction to
900         /// the chain and rejecting new HTLCs on the given channel.
901         pub fn force_close_channel(&self, channel_id: &[u8; 32]) {
902                 let _ = self.total_consistency_lock.read().unwrap();
903
904                 let mut chan = {
905                         let mut channel_state_lock = self.channel_state.lock().unwrap();
906                         let channel_state = &mut *channel_state_lock;
907                         if let Some(chan) = channel_state.by_id.remove(channel_id) {
908                                 if let Some(short_id) = chan.get_short_channel_id() {
909                                         channel_state.short_to_id.remove(&short_id);
910                                 }
911                                 chan
912                         } else {
913                                 return;
914                         }
915                 };
916                 log_trace!(self.logger, "Force-closing channel {}", log_bytes!(channel_id[..]));
917                 self.finish_force_close_channel(chan.force_shutdown(true));
918                 if let Ok(update) = self.get_channel_update(&chan) {
919                         let mut channel_state = self.channel_state.lock().unwrap();
920                         channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
921                                 msg: update
922                         });
923                 }
924         }
925
926         /// Force close all channels, immediately broadcasting the latest local commitment transaction
927         /// for each to the chain and rejecting new HTLCs on each.
928         pub fn force_close_all_channels(&self) {
929                 for chan in self.list_channels() {
930                         self.force_close_channel(&chan.channel_id);
931                 }
932         }
933
934         fn decode_update_add_htlc_onion(&self, msg: &msgs::UpdateAddHTLC) -> (PendingHTLCStatus, MutexGuard<ChannelHolder<ChanSigner>>) {
935                 macro_rules! return_malformed_err {
936                         ($msg: expr, $err_code: expr) => {
937                                 {
938                                         log_info!(self.logger, "Failed to accept/forward incoming HTLC: {}", $msg);
939                                         return (PendingHTLCStatus::Fail(HTLCFailureMsg::Malformed(msgs::UpdateFailMalformedHTLC {
940                                                 channel_id: msg.channel_id,
941                                                 htlc_id: msg.htlc_id,
942                                                 sha256_of_onion: Sha256::hash(&msg.onion_routing_packet.hop_data).into_inner(),
943                                                 failure_code: $err_code,
944                                         })), self.channel_state.lock().unwrap());
945                                 }
946                         }
947                 }
948
949                 if let Err(_) = msg.onion_routing_packet.public_key {
950                         return_malformed_err!("invalid ephemeral pubkey", 0x8000 | 0x4000 | 6);
951                 }
952
953                 let shared_secret = {
954                         let mut arr = [0; 32];
955                         arr.copy_from_slice(&SharedSecret::new(&msg.onion_routing_packet.public_key.unwrap(), &self.our_network_key)[..]);
956                         arr
957                 };
958                 let (rho, mu) = onion_utils::gen_rho_mu_from_shared_secret(&shared_secret);
959
960                 if msg.onion_routing_packet.version != 0 {
961                         //TODO: Spec doesn't indicate if we should only hash hop_data here (and in other
962                         //sha256_of_onion error data packets), or the entire onion_routing_packet. Either way,
963                         //the hash doesn't really serve any purpose - in the case of hashing all data, the
964                         //receiving node would have to brute force to figure out which version was put in the
965                         //packet by the node that send us the message, in the case of hashing the hop_data, the
966                         //node knows the HMAC matched, so they already know what is there...
967                         return_malformed_err!("Unknown onion packet version", 0x8000 | 0x4000 | 4);
968                 }
969
970                 let mut hmac = HmacEngine::<Sha256>::new(&mu);
971                 hmac.input(&msg.onion_routing_packet.hop_data);
972                 hmac.input(&msg.payment_hash.0[..]);
973                 if !fixed_time_eq(&Hmac::from_engine(hmac).into_inner(), &msg.onion_routing_packet.hmac) {
974                         return_malformed_err!("HMAC Check failed", 0x8000 | 0x4000 | 5);
975                 }
976
977                 let mut channel_state = None;
978                 macro_rules! return_err {
979                         ($msg: expr, $err_code: expr, $data: expr) => {
980                                 {
981                                         log_info!(self.logger, "Failed to accept/forward incoming HTLC: {}", $msg);
982                                         if channel_state.is_none() {
983                                                 channel_state = Some(self.channel_state.lock().unwrap());
984                                         }
985                                         return (PendingHTLCStatus::Fail(HTLCFailureMsg::Relay(msgs::UpdateFailHTLC {
986                                                 channel_id: msg.channel_id,
987                                                 htlc_id: msg.htlc_id,
988                                                 reason: onion_utils::build_first_hop_failure_packet(&shared_secret, $err_code, $data),
989                                         })), channel_state.unwrap());
990                                 }
991                         }
992                 }
993
994                 let mut chacha = ChaCha20::new(&rho, &[0u8; 8]);
995                 let mut chacha_stream = ChaChaReader { chacha: &mut chacha, read: Cursor::new(&msg.onion_routing_packet.hop_data[..]) };
996                 let (next_hop_data, next_hop_hmac) = {
997                         match msgs::OnionHopData::read(&mut chacha_stream) {
998                                 Err(err) => {
999                                         let error_code = match err {
1000                                                 msgs::DecodeError::UnknownVersion => 0x4000 | 1, // unknown realm byte
1001                                                 msgs::DecodeError::UnknownRequiredFeature|
1002                                                 msgs::DecodeError::InvalidValue|
1003                                                 msgs::DecodeError::ShortRead => 0x4000 | 22, // invalid_onion_payload
1004                                                 _ => 0x2000 | 2, // Should never happen
1005                                         };
1006                                         return_err!("Unable to decode our hop data", error_code, &[0;0]);
1007                                 },
1008                                 Ok(msg) => {
1009                                         let mut hmac = [0; 32];
1010                                         if let Err(_) = chacha_stream.read_exact(&mut hmac[..]) {
1011                                                 return_err!("Unable to decode hop data", 0x4000 | 22, &[0;0]);
1012                                         }
1013                                         (msg, hmac)
1014                                 },
1015                         }
1016                 };
1017
1018                 let pending_forward_info = if next_hop_hmac == [0; 32] {
1019                                 #[cfg(test)]
1020                                 {
1021                                         // In tests, make sure that the initial onion pcket data is, at least, non-0.
1022                                         // We could do some fancy randomness test here, but, ehh, whatever.
1023                                         // This checks for the issue where you can calculate the path length given the
1024                                         // onion data as all the path entries that the originator sent will be here
1025                                         // as-is (and were originally 0s).
1026                                         // Of course reverse path calculation is still pretty easy given naive routing
1027                                         // algorithms, but this fixes the most-obvious case.
1028                                         let mut next_bytes = [0; 32];
1029                                         chacha_stream.read_exact(&mut next_bytes).unwrap();
1030                                         assert_ne!(next_bytes[..], [0; 32][..]);
1031                                         chacha_stream.read_exact(&mut next_bytes).unwrap();
1032                                         assert_ne!(next_bytes[..], [0; 32][..]);
1033                                 }
1034
1035                                 // OUR PAYMENT!
1036                                 // final_expiry_too_soon
1037                                 // We have to have some headroom to broadcast on chain if we have the preimage, so make sure we have at least
1038                                 // HTLC_FAIL_BACK_BUFFER blocks to go.
1039                                 // Also, ensure that, in the case of an unknown payment hash, our payment logic has enough time to fail the HTLC backward
1040                                 // before our onchain logic triggers a channel closure (see HTLC_FAIL_BACK_BUFFER rational).
1041                                 if (msg.cltv_expiry as u64) <= self.latest_block_height.load(Ordering::Acquire) as u64 + HTLC_FAIL_BACK_BUFFER as u64 + 1 {
1042                                         return_err!("The final CLTV expiry is too soon to handle", 17, &[0;0]);
1043                                 }
1044                                 // final_incorrect_htlc_amount
1045                                 if next_hop_data.amt_to_forward > msg.amount_msat {
1046                                         return_err!("Upstream node sent less than we were supposed to receive in payment", 19, &byte_utils::be64_to_array(msg.amount_msat));
1047                                 }
1048                                 // final_incorrect_cltv_expiry
1049                                 if next_hop_data.outgoing_cltv_value != msg.cltv_expiry {
1050                                         return_err!("Upstream node set CLTV to the wrong value", 18, &byte_utils::be32_to_array(msg.cltv_expiry));
1051                                 }
1052
1053                                 let payment_data = match next_hop_data.format {
1054                                         msgs::OnionHopDataFormat::Legacy { .. } => None,
1055                                         msgs::OnionHopDataFormat::NonFinalNode { .. } => return_err!("Got non final data with an HMAC of 0", 0x4000 | 22, &[0;0]),
1056                                         msgs::OnionHopDataFormat::FinalNode { payment_data } => payment_data,
1057                                 };
1058
1059                                 // Note that we could obviously respond immediately with an update_fulfill_htlc
1060                                 // message, however that would leak that we are the recipient of this payment, so
1061                                 // instead we stay symmetric with the forwarding case, only responding (after a
1062                                 // delay) once they've send us a commitment_signed!
1063
1064                                 PendingHTLCStatus::Forward(PendingHTLCInfo {
1065                                         routing: PendingHTLCRouting::Receive {
1066                                                 payment_data,
1067                                                 incoming_cltv_expiry: msg.cltv_expiry,
1068                                         },
1069                                         payment_hash: msg.payment_hash.clone(),
1070                                         incoming_shared_secret: shared_secret,
1071                                         amt_to_forward: next_hop_data.amt_to_forward,
1072                                         outgoing_cltv_value: next_hop_data.outgoing_cltv_value,
1073                                 })
1074                         } else {
1075                                 let mut new_packet_data = [0; 20*65];
1076                                 let read_pos = chacha_stream.read(&mut new_packet_data).unwrap();
1077                                 #[cfg(debug_assertions)]
1078                                 {
1079                                         // Check two things:
1080                                         // a) that the behavior of our stream here will return Ok(0) even if the TLV
1081                                         //    read above emptied out our buffer and the unwrap() wont needlessly panic
1082                                         // b) that we didn't somehow magically end up with extra data.
1083                                         let mut t = [0; 1];
1084                                         debug_assert!(chacha_stream.read(&mut t).unwrap() == 0);
1085                                 }
1086                                 // Once we've emptied the set of bytes our peer gave us, encrypt 0 bytes until we
1087                                 // fill the onion hop data we'll forward to our next-hop peer.
1088                                 chacha_stream.chacha.process_in_place(&mut new_packet_data[read_pos..]);
1089
1090                                 let mut new_pubkey = msg.onion_routing_packet.public_key.unwrap();
1091
1092                                 let blinding_factor = {
1093                                         let mut sha = Sha256::engine();
1094                                         sha.input(&new_pubkey.serialize()[..]);
1095                                         sha.input(&shared_secret);
1096                                         Sha256::from_engine(sha).into_inner()
1097                                 };
1098
1099                                 let public_key = if let Err(e) = new_pubkey.mul_assign(&self.secp_ctx, &blinding_factor[..]) {
1100                                         Err(e)
1101                                 } else { Ok(new_pubkey) };
1102
1103                                 let outgoing_packet = msgs::OnionPacket {
1104                                         version: 0,
1105                                         public_key,
1106                                         hop_data: new_packet_data,
1107                                         hmac: next_hop_hmac.clone(),
1108                                 };
1109
1110                                 let short_channel_id = match next_hop_data.format {
1111                                         msgs::OnionHopDataFormat::Legacy { short_channel_id } => short_channel_id,
1112                                         msgs::OnionHopDataFormat::NonFinalNode { short_channel_id } => short_channel_id,
1113                                         msgs::OnionHopDataFormat::FinalNode { .. } => {
1114                                                 return_err!("Final Node OnionHopData provided for us as an intermediary node", 0x4000 | 22, &[0;0]);
1115                                         },
1116                                 };
1117
1118                                 PendingHTLCStatus::Forward(PendingHTLCInfo {
1119                                         routing: PendingHTLCRouting::Forward {
1120                                                 onion_packet: outgoing_packet,
1121                                                 short_channel_id: short_channel_id,
1122                                         },
1123                                         payment_hash: msg.payment_hash.clone(),
1124                                         incoming_shared_secret: shared_secret,
1125                                         amt_to_forward: next_hop_data.amt_to_forward,
1126                                         outgoing_cltv_value: next_hop_data.outgoing_cltv_value,
1127                                 })
1128                         };
1129
1130                 channel_state = Some(self.channel_state.lock().unwrap());
1131                 if let &PendingHTLCStatus::Forward(PendingHTLCInfo { ref routing, ref amt_to_forward, ref outgoing_cltv_value, .. }) = &pending_forward_info {
1132                         // If short_channel_id is 0 here, we'll reject the HTLC as there cannot be a channel
1133                         // with a short_channel_id of 0. This is important as various things later assume
1134                         // short_channel_id is non-0 in any ::Forward.
1135                         if let &PendingHTLCRouting::Forward { ref short_channel_id, .. } = routing {
1136                                 let id_option = channel_state.as_ref().unwrap().short_to_id.get(&short_channel_id).cloned();
1137                                 let forwarding_id = match id_option {
1138                                         None => { // unknown_next_peer
1139                                                 return_err!("Don't have available channel for forwarding as requested.", 0x4000 | 10, &[0;0]);
1140                                         },
1141                                         Some(id) => id.clone(),
1142                                 };
1143                                 if let Some((err, code, chan_update)) = loop {
1144                                         let chan = channel_state.as_mut().unwrap().by_id.get_mut(&forwarding_id).unwrap();
1145
1146                                         // Note that we could technically not return an error yet here and just hope
1147                                         // that the connection is reestablished or monitor updated by the time we get
1148                                         // around to doing the actual forward, but better to fail early if we can and
1149                                         // hopefully an attacker trying to path-trace payments cannot make this occur
1150                                         // on a small/per-node/per-channel scale.
1151                                         if !chan.is_live() { // channel_disabled
1152                                                 break Some(("Forwarding channel is not in a ready state.", 0x1000 | 20, Some(self.get_channel_update(chan).unwrap())));
1153                                         }
1154                                         if *amt_to_forward < chan.get_their_htlc_minimum_msat() { // amount_below_minimum
1155                                                 break Some(("HTLC amount was below the htlc_minimum_msat", 0x1000 | 11, Some(self.get_channel_update(chan).unwrap())));
1156                                         }
1157                                         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) });
1158                                         if fee.is_none() || msg.amount_msat < fee.unwrap() || (msg.amount_msat - fee.unwrap()) < *amt_to_forward { // fee_insufficient
1159                                                 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())));
1160                                         }
1161                                         if (msg.cltv_expiry as u64) < (*outgoing_cltv_value) as u64 + CLTV_EXPIRY_DELTA as u64 { // incorrect_cltv_expiry
1162                                                 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())));
1163                                         }
1164                                         let cur_height = self.latest_block_height.load(Ordering::Acquire) as u32 + 1;
1165                                         // Theoretically, channel counterparty shouldn't send us a HTLC expiring now, but we want to be robust wrt to counterparty
1166                                         // packet sanitization (see HTLC_FAIL_BACK_BUFFER rational)
1167                                         if msg.cltv_expiry <= cur_height + HTLC_FAIL_BACK_BUFFER as u32 { // expiry_too_soon
1168                                                 break Some(("CLTV expiry is too close", 0x1000 | 14, Some(self.get_channel_update(chan).unwrap())));
1169                                         }
1170                                         if msg.cltv_expiry > cur_height + CLTV_FAR_FAR_AWAY as u32 { // expiry_too_far
1171                                                 break Some(("CLTV expiry is too far in the future", 21, None));
1172                                         }
1173                                         // In theory, we would be safe against unitentional channel-closure, if we only required a margin of LATENCY_GRACE_PERIOD_BLOCKS.
1174                                         // But, to be safe against policy reception, we use a longuer delay.
1175                                         if (*outgoing_cltv_value) as u64 <= (cur_height + HTLC_FAIL_BACK_BUFFER) as u64 {
1176                                                 break Some(("Outgoing CLTV value is too soon", 0x1000 | 14, Some(self.get_channel_update(chan).unwrap())));
1177                                         }
1178
1179                                         break None;
1180                                 }
1181                                 {
1182                                         let mut res = Vec::with_capacity(8 + 128);
1183                                         if let Some(chan_update) = chan_update {
1184                                                 if code == 0x1000 | 11 || code == 0x1000 | 12 {
1185                                                         res.extend_from_slice(&byte_utils::be64_to_array(msg.amount_msat));
1186                                                 }
1187                                                 else if code == 0x1000 | 13 {
1188                                                         res.extend_from_slice(&byte_utils::be32_to_array(msg.cltv_expiry));
1189                                                 }
1190                                                 else if code == 0x1000 | 20 {
1191                                                         res.extend_from_slice(&byte_utils::be16_to_array(chan_update.contents.flags));
1192                                                 }
1193                                                 res.extend_from_slice(&chan_update.encode_with_len()[..]);
1194                                         }
1195                                         return_err!(err, code, &res[..]);
1196                                 }
1197                         }
1198                 }
1199
1200                 (pending_forward_info, channel_state.unwrap())
1201         }
1202
1203         /// only fails if the channel does not yet have an assigned short_id
1204         /// May be called with channel_state already locked!
1205         fn get_channel_update(&self, chan: &Channel<ChanSigner>) -> Result<msgs::ChannelUpdate, LightningError> {
1206                 let short_channel_id = match chan.get_short_channel_id() {
1207                         None => return Err(LightningError{err: "Channel not yet established", action: msgs::ErrorAction::IgnoreError}),
1208                         Some(id) => id,
1209                 };
1210
1211                 let were_node_one = PublicKey::from_secret_key(&self.secp_ctx, &self.our_network_key).serialize()[..] < chan.get_their_node_id().serialize()[..];
1212
1213                 let unsigned = msgs::UnsignedChannelUpdate {
1214                         chain_hash: self.genesis_hash,
1215                         short_channel_id: short_channel_id,
1216                         timestamp: chan.get_update_time_counter(),
1217                         flags: (!were_node_one) as u16 | ((!chan.is_live() as u16) << 1),
1218                         cltv_expiry_delta: CLTV_EXPIRY_DELTA,
1219                         htlc_minimum_msat: chan.get_our_htlc_minimum_msat(),
1220                         fee_base_msat: chan.get_our_fee_base_msat(&self.fee_estimator),
1221                         fee_proportional_millionths: chan.get_fee_proportional_millionths(),
1222                         excess_data: Vec::new(),
1223                 };
1224
1225                 let msg_hash = Sha256dHash::hash(&unsigned.encode()[..]);
1226                 let sig = self.secp_ctx.sign(&hash_to_message!(&msg_hash[..]), &self.our_network_key);
1227
1228                 Ok(msgs::ChannelUpdate {
1229                         signature: sig,
1230                         contents: unsigned
1231                 })
1232         }
1233
1234         // Only public for testing, this should otherwise never be called direcly
1235         pub(crate) fn send_payment_along_path(&self, path: &Vec<RouteHop>, payment_hash: &PaymentHash, payment_secret: &Option<PaymentSecret>, total_value: u64, cur_height: u32) -> Result<(), APIError> {
1236                 log_trace!(self.logger, "Attempting to send payment for path with next hop {}", path.first().unwrap().short_channel_id);
1237                 let (session_priv, prng_seed) = self.keys_manager.get_onion_rand();
1238
1239                 let onion_keys = onion_utils::construct_onion_keys(&self.secp_ctx, &path, &session_priv)
1240                         .map_err(|_| APIError::RouteError{err: "Pubkey along hop was maliciously selected"})?;
1241                 let (onion_payloads, htlc_msat, htlc_cltv) = onion_utils::build_onion_payloads(path, total_value, payment_secret, cur_height)?;
1242                 if onion_utils::route_size_insane(&onion_payloads) {
1243                         return Err(APIError::RouteError{err: "Route size too large considering onion data"});
1244                 }
1245                 let onion_packet = onion_utils::construct_onion_packet(onion_payloads, onion_keys, prng_seed, payment_hash);
1246
1247                 let _ = self.total_consistency_lock.read().unwrap();
1248
1249                 let err: Result<(), _> = loop {
1250                         let mut channel_lock = self.channel_state.lock().unwrap();
1251                         let id = match channel_lock.short_to_id.get(&path.first().unwrap().short_channel_id) {
1252                                 None => return Err(APIError::ChannelUnavailable{err: "No channel available with first hop!"}),
1253                                 Some(id) => id.clone(),
1254                         };
1255
1256                         let channel_state = &mut *channel_lock;
1257                         if let hash_map::Entry::Occupied(mut chan) = channel_state.by_id.entry(id) {
1258                                 match {
1259                                         if chan.get().get_their_node_id() != path.first().unwrap().pubkey {
1260                                                 return Err(APIError::RouteError{err: "Node ID mismatch on first hop!"});
1261                                         }
1262                                         if !chan.get().is_live() {
1263                                                 return Err(APIError::ChannelUnavailable{err: "Peer for first hop currently disconnected/pending monitor update!"});
1264                                         }
1265                                         break_chan_entry!(self, chan.get_mut().send_htlc_and_commit(htlc_msat, payment_hash.clone(), htlc_cltv, HTLCSource::OutboundRoute {
1266                                                 path: path.clone(),
1267                                                 session_priv: session_priv.clone(),
1268                                                 first_hop_htlc_msat: htlc_msat,
1269                                         }, onion_packet, &self.logger), channel_state, chan)
1270                                 } {
1271                                         Some((update_add, commitment_signed, monitor_update)) => {
1272                                                 if let Err(e) = self.monitor.update_monitor(chan.get().get_funding_txo().unwrap(), monitor_update) {
1273                                                         maybe_break_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::CommitmentFirst, false, true);
1274                                                         // Note that MonitorUpdateFailed here indicates (per function docs)
1275                                                         // that we will resend the commitment update once monitor updating
1276                                                         // is restored. Therefore, we must return an error indicating that
1277                                                         // it is unsafe to retry the payment wholesale, which we do in the
1278                                                         // send_payment check for MonitorUpdateFailed, below.
1279                                                         return Err(APIError::MonitorUpdateFailed);
1280                                                 }
1281
1282                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
1283                                                         node_id: path.first().unwrap().pubkey,
1284                                                         updates: msgs::CommitmentUpdate {
1285                                                                 update_add_htlcs: vec![update_add],
1286                                                                 update_fulfill_htlcs: Vec::new(),
1287                                                                 update_fail_htlcs: Vec::new(),
1288                                                                 update_fail_malformed_htlcs: Vec::new(),
1289                                                                 update_fee: None,
1290                                                                 commitment_signed,
1291                                                         },
1292                                                 });
1293                                         },
1294                                         None => {},
1295                                 }
1296                         } else { unreachable!(); }
1297                         return Ok(());
1298                 };
1299
1300                 match handle_error!(self, err, path.first().unwrap().pubkey) {
1301                         Ok(_) => unreachable!(),
1302                         Err(e) => {
1303                                 Err(APIError::ChannelUnavailable { err: e.err })
1304                         },
1305                 }
1306         }
1307
1308         /// Sends a payment along a given route.
1309         ///
1310         /// Value parameters are provided via the last hop in route, see documentation for RouteHop
1311         /// fields for more info.
1312         ///
1313         /// Note that if the payment_hash already exists elsewhere (eg you're sending a duplicative
1314         /// payment), we don't do anything to stop you! We always try to ensure that if the provided
1315         /// next hop knows the preimage to payment_hash they can claim an additional amount as
1316         /// specified in the last hop in the route! Thus, you should probably do your own
1317         /// payment_preimage tracking (which you should already be doing as they represent "proof of
1318         /// payment") and prevent double-sends yourself.
1319         ///
1320         /// May generate SendHTLCs message(s) event on success, which should be relayed.
1321         ///
1322         /// Each path may have a different return value, and PaymentSendValue may return a Vec with
1323         /// each entry matching the corresponding-index entry in the route paths, see
1324         /// PaymentSendFailure for more info.
1325         ///
1326         /// In general, a path may raise:
1327         ///  * APIError::RouteError when an invalid route or forwarding parameter (cltv_delta, fee,
1328         ///    node public key) is specified.
1329         ///  * APIError::ChannelUnavailable if the next-hop channel is not available for updates
1330         ///    (including due to previous monitor update failure or new permanent monitor update
1331         ///    failure).
1332         ///  * APIError::MonitorUpdateFailed if a new monitor update failure prevented sending the
1333         ///    relevant updates.
1334         ///
1335         /// Note that depending on the type of the PaymentSendFailure the HTLC may have been
1336         /// irrevocably committed to on our end. In such a case, do NOT retry the payment with a
1337         /// different route unless you intend to pay twice!
1338         ///
1339         /// payment_secret is unrelated to payment_hash (or PaymentPreimage) and exists to authenticate
1340         /// the sender to the recipient and prevent payment-probing (deanonymization) attacks. For
1341         /// newer nodes, it will be provided to you in the invoice. If you do not have one, the Route
1342         /// must not contain multiple paths as multi-path payments require a recipient-provided
1343         /// payment_secret.
1344         /// If a payment_secret *is* provided, we assume that the invoice had the payment_secret feature
1345         /// bit set (either as required or as available). If multiple paths are present in the Route,
1346         /// we assume the invoice had the basic_mpp feature set.
1347         pub fn send_payment(&self, route: &Route, payment_hash: PaymentHash, payment_secret: &Option<PaymentSecret>) -> Result<(), PaymentSendFailure> {
1348                 if route.paths.len() < 1 {
1349                         return Err(PaymentSendFailure::ParameterError(APIError::RouteError{err: "There must be at least one path to send over"}));
1350                 }
1351                 if route.paths.len() > 10 {
1352                         // This limit is completely arbitrary - there aren't any real fundamental path-count
1353                         // limits. After we support retrying individual paths we should likely bump this, but
1354                         // for now more than 10 paths likely carries too much one-path failure.
1355                         return Err(PaymentSendFailure::ParameterError(APIError::RouteError{err: "Sending over more than 10 paths is not currently supported"}));
1356                 }
1357                 let mut total_value = 0;
1358                 let our_node_id = self.get_our_node_id();
1359                 let mut path_errs = Vec::with_capacity(route.paths.len());
1360                 'path_check: for path in route.paths.iter() {
1361                         if path.len() < 1 || path.len() > 20 {
1362                                 path_errs.push(Err(APIError::RouteError{err: "Path didn't go anywhere/had bogus size"}));
1363                                 continue 'path_check;
1364                         }
1365                         for (idx, hop) in path.iter().enumerate() {
1366                                 if idx != path.len() - 1 && hop.pubkey == our_node_id {
1367                                         path_errs.push(Err(APIError::RouteError{err: "Path went through us but wasn't a simple rebalance loop to us"}));
1368                                         continue 'path_check;
1369                                 }
1370                         }
1371                         total_value += path.last().unwrap().fee_msat;
1372                         path_errs.push(Ok(()));
1373                 }
1374                 if path_errs.iter().any(|e| e.is_err()) {
1375                         return Err(PaymentSendFailure::PathParameterError(path_errs));
1376                 }
1377
1378                 let cur_height = self.latest_block_height.load(Ordering::Acquire) as u32 + 1;
1379                 let mut results = Vec::new();
1380                 for path in route.paths.iter() {
1381                         results.push(self.send_payment_along_path(&path, &payment_hash, payment_secret, total_value, cur_height));
1382                 }
1383                 let mut has_ok = false;
1384                 let mut has_err = false;
1385                 for res in results.iter() {
1386                         if res.is_ok() { has_ok = true; }
1387                         if res.is_err() { has_err = true; }
1388                         if let &Err(APIError::MonitorUpdateFailed) = res {
1389                                 // MonitorUpdateFailed is inherently unsafe to retry, so we call it a
1390                                 // PartialFailure.
1391                                 has_err = true;
1392                                 has_ok = true;
1393                                 break;
1394                         }
1395                 }
1396                 if has_err && has_ok {
1397                         Err(PaymentSendFailure::PartialFailure(results))
1398                 } else if has_err {
1399                         Err(PaymentSendFailure::AllFailedRetrySafe(results.drain(..).map(|r| r.unwrap_err()).collect()))
1400                 } else {
1401                         Ok(())
1402                 }
1403         }
1404
1405         /// Call this upon creation of a funding transaction for the given channel.
1406         ///
1407         /// Note that ALL inputs in the transaction pointed to by funding_txo MUST spend SegWit outputs
1408         /// or your counterparty can steal your funds!
1409         ///
1410         /// Panics if a funding transaction has already been provided for this channel.
1411         ///
1412         /// May panic if the funding_txo is duplicative with some other channel (note that this should
1413         /// be trivially prevented by using unique funding transaction keys per-channel).
1414         pub fn funding_transaction_generated(&self, temporary_channel_id: &[u8; 32], funding_txo: OutPoint) {
1415                 let _ = self.total_consistency_lock.read().unwrap();
1416
1417                 let (chan, msg) = {
1418                         let (res, chan) = match self.channel_state.lock().unwrap().by_id.remove(temporary_channel_id) {
1419                                 Some(mut chan) => {
1420                                         (chan.get_outbound_funding_created(funding_txo, &self.logger)
1421                                                 .map_err(|e| if let ChannelError::Close(msg) = e {
1422                                                         MsgHandleErrInternal::from_finish_shutdown(msg, chan.channel_id(), chan.force_shutdown(true), None)
1423                                                 } else { unreachable!(); })
1424                                         , chan)
1425                                 },
1426                                 None => return
1427                         };
1428                         match handle_error!(self, res, chan.get_their_node_id()) {
1429                                 Ok(funding_msg) => {
1430                                         (chan, funding_msg)
1431                                 },
1432                                 Err(_) => { return; }
1433                         }
1434                 };
1435
1436                 let mut channel_state = self.channel_state.lock().unwrap();
1437                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendFundingCreated {
1438                         node_id: chan.get_their_node_id(),
1439                         msg: msg,
1440                 });
1441                 match channel_state.by_id.entry(chan.channel_id()) {
1442                         hash_map::Entry::Occupied(_) => {
1443                                 panic!("Generated duplicate funding txid?");
1444                         },
1445                         hash_map::Entry::Vacant(e) => {
1446                                 e.insert(chan);
1447                         }
1448                 }
1449         }
1450
1451         fn get_announcement_sigs(&self, chan: &Channel<ChanSigner>) -> Option<msgs::AnnouncementSignatures> {
1452                 if !chan.should_announce() {
1453                         log_trace!(self.logger, "Can't send announcement_signatures for private channel {}", log_bytes!(chan.channel_id()));
1454                         return None
1455                 }
1456
1457                 let (announcement, our_bitcoin_sig) = match chan.get_channel_announcement(self.get_our_node_id(), self.genesis_hash.clone()) {
1458                         Ok(res) => res,
1459                         Err(_) => return None, // Only in case of state precondition violations eg channel is closing
1460                 };
1461                 let msghash = hash_to_message!(&Sha256dHash::hash(&announcement.encode()[..])[..]);
1462                 let our_node_sig = self.secp_ctx.sign(&msghash, &self.our_network_key);
1463
1464                 Some(msgs::AnnouncementSignatures {
1465                         channel_id: chan.channel_id(),
1466                         short_channel_id: chan.get_short_channel_id().unwrap(),
1467                         node_signature: our_node_sig,
1468                         bitcoin_signature: our_bitcoin_sig,
1469                 })
1470         }
1471
1472         #[allow(dead_code)]
1473         // Messages of up to 64KB should never end up more than half full with addresses, as that would
1474         // be absurd. We ensure this by checking that at least 500 (our stated public contract on when
1475         // broadcast_node_announcement panics) of the maximum-length addresses would fit in a 64KB
1476         // message...
1477         const HALF_MESSAGE_IS_ADDRS: u32 = ::std::u16::MAX as u32 / (msgs::NetAddress::MAX_LEN as u32 + 1) / 2;
1478         #[deny(const_err)]
1479         #[allow(dead_code)]
1480         // ...by failing to compile if the number of addresses that would be half of a message is
1481         // smaller than 500:
1482         const STATIC_ASSERT: u32 = Self::HALF_MESSAGE_IS_ADDRS - 500;
1483
1484         /// Generates a signed node_announcement from the given arguments and creates a
1485         /// BroadcastNodeAnnouncement event. Note that such messages will be ignored unless peers have
1486         /// seen a channel_announcement from us (ie unless we have public channels open).
1487         ///
1488         /// RGB is a node "color" and alias is a printable human-readable string to describe this node
1489         /// to humans. They carry no in-protocol meaning.
1490         ///
1491         /// addresses represent the set (possibly empty) of socket addresses on which this node accepts
1492         /// incoming connections. These will be broadcast to the network, publicly tying these
1493         /// addresses together. If you wish to preserve user privacy, addresses should likely contain
1494         /// only Tor Onion addresses.
1495         ///
1496         /// Panics if addresses is absurdly large (more than 500).
1497         pub fn broadcast_node_announcement(&self, rgb: [u8; 3], alias: [u8; 32], addresses: Vec<msgs::NetAddress>) {
1498                 let _ = self.total_consistency_lock.read().unwrap();
1499
1500                 if addresses.len() > 500 {
1501                         panic!("More than half the message size was taken up by public addresses!");
1502                 }
1503
1504                 let announcement = msgs::UnsignedNodeAnnouncement {
1505                         features: NodeFeatures::known(),
1506                         timestamp: self.last_node_announcement_serial.fetch_add(1, Ordering::AcqRel) as u32,
1507                         node_id: self.get_our_node_id(),
1508                         rgb, alias, addresses,
1509                         excess_address_data: Vec::new(),
1510                         excess_data: Vec::new(),
1511                 };
1512                 let msghash = hash_to_message!(&Sha256dHash::hash(&announcement.encode()[..])[..]);
1513
1514                 let mut channel_state = self.channel_state.lock().unwrap();
1515                 channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastNodeAnnouncement {
1516                         msg: msgs::NodeAnnouncement {
1517                                 signature: self.secp_ctx.sign(&msghash, &self.our_network_key),
1518                                 contents: announcement
1519                         },
1520                 });
1521         }
1522
1523         /// Processes HTLCs which are pending waiting on random forward delay.
1524         ///
1525         /// Should only really ever be called in response to a PendingHTLCsForwardable event.
1526         /// Will likely generate further events.
1527         pub fn process_pending_htlc_forwards(&self) {
1528                 let _ = self.total_consistency_lock.read().unwrap();
1529
1530                 let mut new_events = Vec::new();
1531                 let mut failed_forwards = Vec::new();
1532                 let mut handle_errors = Vec::new();
1533                 {
1534                         let mut channel_state_lock = self.channel_state.lock().unwrap();
1535                         let channel_state = &mut *channel_state_lock;
1536
1537                         for (short_chan_id, mut pending_forwards) in channel_state.forward_htlcs.drain() {
1538                                 if short_chan_id != 0 {
1539                                         let forward_chan_id = match channel_state.short_to_id.get(&short_chan_id) {
1540                                                 Some(chan_id) => chan_id.clone(),
1541                                                 None => {
1542                                                         failed_forwards.reserve(pending_forwards.len());
1543                                                         for forward_info in pending_forwards.drain(..) {
1544                                                                 match forward_info {
1545                                                                         HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info } => {
1546                                                                                 let htlc_source = HTLCSource::PreviousHopData(HTLCPreviousHopData {
1547                                                                                         short_channel_id: prev_short_channel_id,
1548                                                                                         htlc_id: prev_htlc_id,
1549                                                                                         incoming_packet_shared_secret: forward_info.incoming_shared_secret,
1550                                                                                 });
1551                                                                                 failed_forwards.push((htlc_source, forward_info.payment_hash,
1552                                                                                         HTLCFailReason::Reason { failure_code: 0x4000 | 10, data: Vec::new() }
1553                                                                                 ));
1554                                                                         },
1555                                                                         HTLCForwardInfo::FailHTLC { .. } => {
1556                                                                                 // Channel went away before we could fail it. This implies
1557                                                                                 // the channel is now on chain and our counterparty is
1558                                                                                 // trying to broadcast the HTLC-Timeout, but that's their
1559                                                                                 // problem, not ours.
1560                                                                         }
1561                                                                 }
1562                                                         }
1563                                                         continue;
1564                                                 }
1565                                         };
1566                                         if let hash_map::Entry::Occupied(mut chan) = channel_state.by_id.entry(forward_chan_id) {
1567                                                 let mut add_htlc_msgs = Vec::new();
1568                                                 let mut fail_htlc_msgs = Vec::new();
1569                                                 for forward_info in pending_forwards.drain(..) {
1570                                                         match forward_info {
1571                                                                 HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info: PendingHTLCInfo {
1572                                                                                 routing: PendingHTLCRouting::Forward {
1573                                                                                         onion_packet, ..
1574                                                                                 }, incoming_shared_secret, payment_hash, amt_to_forward, outgoing_cltv_value }, } => {
1575                                                                         log_trace!(self.logger, "Adding HTLC from short id {} with payment_hash {} to channel with short id {} after delay", log_bytes!(payment_hash.0), prev_short_channel_id, short_chan_id);
1576                                                                         let htlc_source = HTLCSource::PreviousHopData(HTLCPreviousHopData {
1577                                                                                 short_channel_id: prev_short_channel_id,
1578                                                                                 htlc_id: prev_htlc_id,
1579                                                                                 incoming_packet_shared_secret: incoming_shared_secret,
1580                                                                         });
1581                                                                         match chan.get_mut().send_htlc(amt_to_forward, payment_hash, outgoing_cltv_value, htlc_source.clone(), onion_packet) {
1582                                                                                 Err(e) => {
1583                                                                                         if let ChannelError::Ignore(msg) = e {
1584                                                                                                 log_trace!(self.logger, "Failed to forward HTLC with payment_hash {}: {}", log_bytes!(payment_hash.0), msg);
1585                                                                                         } else {
1586                                                                                                 panic!("Stated return value requirements in send_htlc() were not met");
1587                                                                                         }
1588                                                                                         let chan_update = self.get_channel_update(chan.get()).unwrap();
1589                                                                                         failed_forwards.push((htlc_source, payment_hash,
1590                                                                                                 HTLCFailReason::Reason { failure_code: 0x1000 | 7, data: chan_update.encode_with_len() }
1591                                                                                         ));
1592                                                                                         continue;
1593                                                                                 },
1594                                                                                 Ok(update_add) => {
1595                                                                                         match update_add {
1596                                                                                                 Some(msg) => { add_htlc_msgs.push(msg); },
1597                                                                                                 None => {
1598                                                                                                         // Nothing to do here...we're waiting on a remote
1599                                                                                                         // revoke_and_ack before we can add anymore HTLCs. The Channel
1600                                                                                                         // will automatically handle building the update_add_htlc and
1601                                                                                                         // commitment_signed messages when we can.
1602                                                                                                         // TODO: Do some kind of timer to set the channel as !is_live()
1603                                                                                                         // as we don't really want others relying on us relaying through
1604                                                                                                         // this channel currently :/.
1605                                                                                                 }
1606                                                                                         }
1607                                                                                 }
1608                                                                         }
1609                                                                 },
1610                                                                 HTLCForwardInfo::AddHTLC { .. } => {
1611                                                                         panic!("short_channel_id != 0 should imply any pending_forward entries are of type Forward");
1612                                                                 },
1613                                                                 HTLCForwardInfo::FailHTLC { htlc_id, err_packet } => {
1614                                                                         log_trace!(self.logger, "Failing HTLC back to channel with short id {} after delay", short_chan_id);
1615                                                                         match chan.get_mut().get_update_fail_htlc(htlc_id, err_packet) {
1616                                                                                 Err(e) => {
1617                                                                                         if let ChannelError::Ignore(msg) = e {
1618                                                                                                 log_trace!(self.logger, "Failed to fail backwards to short_id {}: {}", short_chan_id, msg);
1619                                                                                         } else {
1620                                                                                                 panic!("Stated return value requirements in get_update_fail_htlc() were not met");
1621                                                                                         }
1622                                                                                         // fail-backs are best-effort, we probably already have one
1623                                                                                         // pending, and if not that's OK, if not, the channel is on
1624                                                                                         // the chain and sending the HTLC-Timeout is their problem.
1625                                                                                         continue;
1626                                                                                 },
1627                                                                                 Ok(Some(msg)) => { fail_htlc_msgs.push(msg); },
1628                                                                                 Ok(None) => {
1629                                                                                         // Nothing to do here...we're waiting on a remote
1630                                                                                         // revoke_and_ack before we can update the commitment
1631                                                                                         // transaction. The Channel will automatically handle
1632                                                                                         // building the update_fail_htlc and commitment_signed
1633                                                                                         // messages when we can.
1634                                                                                         // We don't need any kind of timer here as they should fail
1635                                                                                         // the channel onto the chain if they can't get our
1636                                                                                         // update_fail_htlc in time, it's not our problem.
1637                                                                                 }
1638                                                                         }
1639                                                                 },
1640                                                         }
1641                                                 }
1642
1643                                                 if !add_htlc_msgs.is_empty() || !fail_htlc_msgs.is_empty() {
1644                                                         let (commitment_msg, monitor_update) = match chan.get_mut().send_commitment(&self.logger) {
1645                                                                 Ok(res) => res,
1646                                                                 Err(e) => {
1647                                                                         // We surely failed send_commitment due to bad keys, in that case
1648                                                                         // close channel and then send error message to peer.
1649                                                                         let their_node_id = chan.get().get_their_node_id();
1650                                                                         let err: Result<(), _>  = match e {
1651                                                                                 ChannelError::Ignore(_) => {
1652                                                                                         panic!("Stated return value requirements in send_commitment() were not met");
1653                                                                                 },
1654                                                                                 ChannelError::Close(msg) => {
1655                                                                                         log_trace!(self.logger, "Closing channel {} due to Close-required error: {}", log_bytes!(chan.key()[..]), msg);
1656                                                                                         let (channel_id, mut channel) = chan.remove_entry();
1657                                                                                         if let Some(short_id) = channel.get_short_channel_id() {
1658                                                                                                 channel_state.short_to_id.remove(&short_id);
1659                                                                                         }
1660                                                                                         Err(MsgHandleErrInternal::from_finish_shutdown(msg, channel_id, channel.force_shutdown(true), self.get_channel_update(&channel).ok()))
1661                                                                                 },
1662                                                                                 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"); }
1663                                                                         };
1664                                                                         handle_errors.push((their_node_id, err));
1665                                                                         continue;
1666                                                                 }
1667                                                         };
1668                                                         if let Err(e) = self.monitor.update_monitor(chan.get().get_funding_txo().unwrap(), monitor_update) {
1669                                                                 handle_errors.push((chan.get().get_their_node_id(), handle_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::CommitmentFirst, false, true)));
1670                                                                 continue;
1671                                                         }
1672                                                         channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
1673                                                                 node_id: chan.get().get_their_node_id(),
1674                                                                 updates: msgs::CommitmentUpdate {
1675                                                                         update_add_htlcs: add_htlc_msgs,
1676                                                                         update_fulfill_htlcs: Vec::new(),
1677                                                                         update_fail_htlcs: fail_htlc_msgs,
1678                                                                         update_fail_malformed_htlcs: Vec::new(),
1679                                                                         update_fee: None,
1680                                                                         commitment_signed: commitment_msg,
1681                                                                 },
1682                                                         });
1683                                                 }
1684                                         } else {
1685                                                 unreachable!();
1686                                         }
1687                                 } else {
1688                                         for forward_info in pending_forwards.drain(..) {
1689                                                 match forward_info {
1690                                                         HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info: PendingHTLCInfo {
1691                                                                         routing: PendingHTLCRouting::Receive { payment_data, incoming_cltv_expiry },
1692                                                                         incoming_shared_secret, payment_hash, amt_to_forward, .. }, } => {
1693                                                                 let prev_hop = HTLCPreviousHopData {
1694                                                                         short_channel_id: prev_short_channel_id,
1695                                                                         htlc_id: prev_htlc_id,
1696                                                                         incoming_packet_shared_secret: incoming_shared_secret,
1697                                                                 };
1698
1699                                                                 let mut total_value = 0;
1700                                                                 let payment_secret_opt =
1701                                                                         if let &Some(ref data) = &payment_data { Some(data.payment_secret.clone()) } else { None };
1702                                                                 let htlcs = channel_state.claimable_htlcs.entry((payment_hash, payment_secret_opt))
1703                                                                         .or_insert(Vec::new());
1704                                                                 htlcs.push(ClaimableHTLC {
1705                                                                         prev_hop,
1706                                                                         value: amt_to_forward,
1707                                                                         payment_data: payment_data.clone(),
1708                                                                         cltv_expiry: incoming_cltv_expiry,
1709                                                                 });
1710                                                                 if let &Some(ref data) = &payment_data {
1711                                                                         for htlc in htlcs.iter() {
1712                                                                                 total_value += htlc.value;
1713                                                                                 if htlc.payment_data.as_ref().unwrap().total_msat != data.total_msat {
1714                                                                                         total_value = msgs::MAX_VALUE_MSAT;
1715                                                                                 }
1716                                                                                 if total_value >= msgs::MAX_VALUE_MSAT { break; }
1717                                                                         }
1718                                                                         if total_value >= msgs::MAX_VALUE_MSAT || total_value > data.total_msat  {
1719                                                                                 for htlc in htlcs.iter() {
1720                                                                                         let mut htlc_msat_height_data = byte_utils::be64_to_array(htlc.value).to_vec();
1721                                                                                         htlc_msat_height_data.extend_from_slice(
1722                                                                                                 &byte_utils::be32_to_array(
1723                                                                                                         self.latest_block_height.load(Ordering::Acquire)
1724                                                                                                                 as u32,
1725                                                                                                 ),
1726                                                                                         );
1727                                                                                         failed_forwards.push((HTLCSource::PreviousHopData(HTLCPreviousHopData {
1728                                                                                                         short_channel_id: htlc.prev_hop.short_channel_id,
1729                                                                                                         htlc_id: htlc.prev_hop.htlc_id,
1730                                                                                                         incoming_packet_shared_secret: htlc.prev_hop.incoming_packet_shared_secret,
1731                                                                                                 }), payment_hash,
1732                                                                                                 HTLCFailReason::Reason { failure_code: 0x4000 | 15, data: htlc_msat_height_data }
1733                                                                                         ));
1734                                                                                 }
1735                                                                         } else if total_value == data.total_msat {
1736                                                                                 new_events.push(events::Event::PaymentReceived {
1737                                                                                         payment_hash: payment_hash,
1738                                                                                         payment_secret: Some(data.payment_secret),
1739                                                                                         amt: total_value,
1740                                                                                 });
1741                                                                         }
1742                                                                 } else {
1743                                                                         new_events.push(events::Event::PaymentReceived {
1744                                                                                 payment_hash: payment_hash,
1745                                                                                 payment_secret: None,
1746                                                                                 amt: amt_to_forward,
1747                                                                         });
1748                                                                 }
1749                                                         },
1750                                                         HTLCForwardInfo::AddHTLC { .. } => {
1751                                                                 panic!("short_channel_id == 0 should imply any pending_forward entries are of type Receive");
1752                                                         },
1753                                                         HTLCForwardInfo::FailHTLC { .. } => {
1754                                                                 panic!("Got pending fail of our own HTLC");
1755                                                         }
1756                                                 }
1757                                         }
1758                                 }
1759                         }
1760                 }
1761
1762                 for (htlc_source, payment_hash, failure_reason) in failed_forwards.drain(..) {
1763                         self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), htlc_source, &payment_hash, failure_reason);
1764                 }
1765
1766                 for (their_node_id, err) in handle_errors.drain(..) {
1767                         let _ = handle_error!(self, err, their_node_id);
1768                 }
1769
1770                 if new_events.is_empty() { return }
1771                 let mut events = self.pending_events.lock().unwrap();
1772                 events.append(&mut new_events);
1773         }
1774
1775         /// If a peer is disconnected we mark any channels with that peer as 'disabled'.
1776         /// After some time, if channels are still disabled we need to broadcast a ChannelUpdate
1777         /// to inform the network about the uselessness of these channels.
1778         ///
1779         /// This method handles all the details, and must be called roughly once per minute.
1780         pub fn timer_chan_freshness_every_min(&self) {
1781                 let _ = self.total_consistency_lock.read().unwrap();
1782                 let mut channel_state_lock = self.channel_state.lock().unwrap();
1783                 let channel_state = &mut *channel_state_lock;
1784                 for (_, chan) in channel_state.by_id.iter_mut() {
1785                         if chan.is_disabled_staged() && !chan.is_live() {
1786                                 if let Ok(update) = self.get_channel_update(&chan) {
1787                                         channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
1788                                                 msg: update
1789                                         });
1790                                 }
1791                                 chan.to_fresh();
1792                         } else if chan.is_disabled_staged() && chan.is_live() {
1793                                 chan.to_fresh();
1794                         } else if chan.is_disabled_marked() {
1795                                 chan.to_disabled_staged();
1796                         }
1797                 }
1798         }
1799
1800         /// Indicates that the preimage for payment_hash is unknown or the received amount is incorrect
1801         /// after a PaymentReceived event, failing the HTLC back to its origin and freeing resources
1802         /// along the path (including in our own channel on which we received it).
1803         /// Returns false if no payment was found to fail backwards, true if the process of failing the
1804         /// HTLC backwards has been started.
1805         pub fn fail_htlc_backwards(&self, payment_hash: &PaymentHash, payment_secret: &Option<PaymentSecret>) -> bool {
1806                 let _ = self.total_consistency_lock.read().unwrap();
1807
1808                 let mut channel_state = Some(self.channel_state.lock().unwrap());
1809                 let removed_source = channel_state.as_mut().unwrap().claimable_htlcs.remove(&(*payment_hash, *payment_secret));
1810                 if let Some(mut sources) = removed_source {
1811                         for htlc in sources.drain(..) {
1812                                 if channel_state.is_none() { channel_state = Some(self.channel_state.lock().unwrap()); }
1813                                 let mut htlc_msat_height_data = byte_utils::be64_to_array(htlc.value).to_vec();
1814                                 htlc_msat_height_data.extend_from_slice(&byte_utils::be32_to_array(
1815                                         self.latest_block_height.load(Ordering::Acquire) as u32,
1816                                 ));
1817                                 self.fail_htlc_backwards_internal(channel_state.take().unwrap(),
1818                                                 HTLCSource::PreviousHopData(htlc.prev_hop), payment_hash,
1819                                                 HTLCFailReason::Reason { failure_code: 0x4000 | 15, data: htlc_msat_height_data });
1820                         }
1821                         true
1822                 } else { false }
1823         }
1824
1825         /// Fails an HTLC backwards to the sender of it to us.
1826         /// Note that while we take a channel_state lock as input, we do *not* assume consistency here.
1827         /// There are several callsites that do stupid things like loop over a list of payment_hashes
1828         /// to fail and take the channel_state lock for each iteration (as we take ownership and may
1829         /// drop it). In other words, no assumptions are made that entries in claimable_htlcs point to
1830         /// still-available channels.
1831         fn fail_htlc_backwards_internal(&self, mut channel_state_lock: MutexGuard<ChannelHolder<ChanSigner>>, source: HTLCSource, payment_hash: &PaymentHash, onion_error: HTLCFailReason) {
1832                 //TODO: There is a timing attack here where if a node fails an HTLC back to us they can
1833                 //identify whether we sent it or not based on the (I presume) very different runtime
1834                 //between the branches here. We should make this async and move it into the forward HTLCs
1835                 //timer handling.
1836                 match source {
1837                         HTLCSource::OutboundRoute { ref path, .. } => {
1838                                 log_trace!(self.logger, "Failing outbound payment HTLC with payment_hash {}", log_bytes!(payment_hash.0));
1839                                 mem::drop(channel_state_lock);
1840                                 match &onion_error {
1841                                         &HTLCFailReason::LightningError { ref err } => {
1842 #[cfg(test)]
1843                                                 let (channel_update, payment_retryable, onion_error_code, onion_error_data) = onion_utils::process_onion_failure(&self.secp_ctx, &self.logger, &source, err.data.clone());
1844 #[cfg(not(test))]
1845                                                 let (channel_update, payment_retryable, _, _) = onion_utils::process_onion_failure(&self.secp_ctx, &self.logger, &source, err.data.clone());
1846                                                 // TODO: If we decided to blame ourselves (or one of our channels) in
1847                                                 // process_onion_failure we should close that channel as it implies our
1848                                                 // next-hop is needlessly blaming us!
1849                                                 if let Some(update) = channel_update {
1850                                                         self.channel_state.lock().unwrap().pending_msg_events.push(
1851                                                                 events::MessageSendEvent::PaymentFailureNetworkUpdate {
1852                                                                         update,
1853                                                                 }
1854                                                         );
1855                                                 }
1856                                                 self.pending_events.lock().unwrap().push(
1857                                                         events::Event::PaymentFailed {
1858                                                                 payment_hash: payment_hash.clone(),
1859                                                                 rejected_by_dest: !payment_retryable,
1860 #[cfg(test)]
1861                                                                 error_code: onion_error_code,
1862 #[cfg(test)]
1863                                                                 error_data: onion_error_data
1864                                                         }
1865                                                 );
1866                                         },
1867                                         &HTLCFailReason::Reason {
1868 #[cfg(test)]
1869                                                         ref failure_code,
1870 #[cfg(test)]
1871                                                         ref data,
1872                                                         .. } => {
1873                                                 // we get a fail_malformed_htlc from the first hop
1874                                                 // TODO: We'd like to generate a PaymentFailureNetworkUpdate for temporary
1875                                                 // failures here, but that would be insufficient as get_route
1876                                                 // generally ignores its view of our own channels as we provide them via
1877                                                 // ChannelDetails.
1878                                                 // TODO: For non-temporary failures, we really should be closing the
1879                                                 // channel here as we apparently can't relay through them anyway.
1880                                                 self.pending_events.lock().unwrap().push(
1881                                                         events::Event::PaymentFailed {
1882                                                                 payment_hash: payment_hash.clone(),
1883                                                                 rejected_by_dest: path.len() == 1,
1884 #[cfg(test)]
1885                                                                 error_code: Some(*failure_code),
1886 #[cfg(test)]
1887                                                                 error_data: Some(data.clone()),
1888                                                         }
1889                                                 );
1890                                         }
1891                                 }
1892                         },
1893                         HTLCSource::PreviousHopData(HTLCPreviousHopData { short_channel_id, htlc_id, incoming_packet_shared_secret }) => {
1894                                 let err_packet = match onion_error {
1895                                         HTLCFailReason::Reason { failure_code, data } => {
1896                                                 log_trace!(self.logger, "Failing HTLC with payment_hash {} backwards from us with code {}", log_bytes!(payment_hash.0), failure_code);
1897                                                 let packet = onion_utils::build_failure_packet(&incoming_packet_shared_secret, failure_code, &data[..]).encode();
1898                                                 onion_utils::encrypt_failure_packet(&incoming_packet_shared_secret, &packet)
1899                                         },
1900                                         HTLCFailReason::LightningError { err } => {
1901                                                 log_trace!(self.logger, "Failing HTLC with payment_hash {} backwards with pre-built LightningError", log_bytes!(payment_hash.0));
1902                                                 onion_utils::encrypt_failure_packet(&incoming_packet_shared_secret, &err.data)
1903                                         }
1904                                 };
1905
1906                                 let mut forward_event = None;
1907                                 if channel_state_lock.forward_htlcs.is_empty() {
1908                                         forward_event = Some(Duration::from_millis(MIN_HTLC_RELAY_HOLDING_CELL_MILLIS));
1909                                 }
1910                                 match channel_state_lock.forward_htlcs.entry(short_channel_id) {
1911                                         hash_map::Entry::Occupied(mut entry) => {
1912                                                 entry.get_mut().push(HTLCForwardInfo::FailHTLC { htlc_id, err_packet });
1913                                         },
1914                                         hash_map::Entry::Vacant(entry) => {
1915                                                 entry.insert(vec!(HTLCForwardInfo::FailHTLC { htlc_id, err_packet }));
1916                                         }
1917                                 }
1918                                 mem::drop(channel_state_lock);
1919                                 if let Some(time) = forward_event {
1920                                         let mut pending_events = self.pending_events.lock().unwrap();
1921                                         pending_events.push(events::Event::PendingHTLCsForwardable {
1922                                                 time_forwardable: time
1923                                         });
1924                                 }
1925                         },
1926                 }
1927         }
1928
1929         /// Provides a payment preimage in response to a PaymentReceived event, returning true and
1930         /// generating message events for the net layer to claim the payment, if possible. Thus, you
1931         /// should probably kick the net layer to go send messages if this returns true!
1932         ///
1933         /// You must specify the expected amounts for this HTLC, and we will only claim HTLCs
1934         /// available within a few percent of the expected amount. This is critical for several
1935         /// reasons : a) it avoids providing senders with `proof-of-payment` (in the form of the
1936         /// payment_preimage without having provided the full value and b) it avoids certain
1937         /// privacy-breaking recipient-probing attacks which may reveal payment activity to
1938         /// motivated attackers.
1939         ///
1940         /// Note that the privacy concerns in (b) are not relevant in payments with a payment_secret
1941         /// set. Thus, for such payments we will claim any payments which do not under-pay.
1942         ///
1943         /// May panic if called except in response to a PaymentReceived event.
1944         pub fn claim_funds(&self, payment_preimage: PaymentPreimage, payment_secret: &Option<PaymentSecret>, expected_amount: u64) -> bool {
1945                 let payment_hash = PaymentHash(Sha256::hash(&payment_preimage.0).into_inner());
1946
1947                 let _ = self.total_consistency_lock.read().unwrap();
1948
1949                 let mut channel_state = Some(self.channel_state.lock().unwrap());
1950                 let removed_source = channel_state.as_mut().unwrap().claimable_htlcs.remove(&(payment_hash, *payment_secret));
1951                 if let Some(mut sources) = removed_source {
1952                         assert!(!sources.is_empty());
1953
1954                         // If we are claiming an MPP payment, we have to take special care to ensure that each
1955                         // channel exists before claiming all of the payments (inside one lock).
1956                         // Note that channel existance is sufficient as we should always get a monitor update
1957                         // which will take care of the real HTLC claim enforcement.
1958                         //
1959                         // If we find an HTLC which we would need to claim but for which we do not have a
1960                         // channel, we will fail all parts of the MPP payment. While we could wait and see if
1961                         // the sender retries the already-failed path(s), it should be a pretty rare case where
1962                         // we got all the HTLCs and then a channel closed while we were waiting for the user to
1963                         // provide the preimage, so worrying too much about the optimal handling isn't worth
1964                         // it.
1965
1966                         let (is_mpp, mut valid_mpp) = if let &Some(ref data) = &sources[0].payment_data {
1967                                 assert!(payment_secret.is_some());
1968                                 (true, data.total_msat >= expected_amount)
1969                         } else {
1970                                 assert!(payment_secret.is_none());
1971                                 (false, false)
1972                         };
1973
1974                         for htlc in sources.iter() {
1975                                 if !is_mpp || !valid_mpp { break; }
1976                                 if let None = channel_state.as_ref().unwrap().short_to_id.get(&htlc.prev_hop.short_channel_id) {
1977                                         valid_mpp = false;
1978                                 }
1979                         }
1980
1981                         let mut errs = Vec::new();
1982                         let mut claimed_any_htlcs = false;
1983                         for htlc in sources.drain(..) {
1984                                 if channel_state.is_none() { channel_state = Some(self.channel_state.lock().unwrap()); }
1985                                 if (is_mpp && !valid_mpp) || (!is_mpp && (htlc.value < expected_amount || htlc.value > expected_amount * 2)) {
1986                                         let mut htlc_msat_height_data = byte_utils::be64_to_array(htlc.value).to_vec();
1987                                         htlc_msat_height_data.extend_from_slice(&byte_utils::be32_to_array(
1988                                                 self.latest_block_height.load(Ordering::Acquire) as u32,
1989                                         ));
1990                                         self.fail_htlc_backwards_internal(channel_state.take().unwrap(),
1991                                                                          HTLCSource::PreviousHopData(htlc.prev_hop), &payment_hash,
1992                                                                          HTLCFailReason::Reason { failure_code: 0x4000|15, data: htlc_msat_height_data });
1993                                 } else {
1994                                         match self.claim_funds_from_hop(channel_state.as_mut().unwrap(), htlc.prev_hop, payment_preimage) {
1995                                                 Err(Some(e)) => {
1996                                                         if let msgs::ErrorAction::IgnoreError = e.1.err.action {
1997                                                                 // We got a temporary failure updating monitor, but will claim the
1998                                                                 // HTLC when the monitor updating is restored (or on chain).
1999                                                                 log_error!(self.logger, "Temporary failure claiming HTLC, treating as success: {}", e.1.err.err);
2000                                                                 claimed_any_htlcs = true;
2001                                                         } else { errs.push(e); }
2002                                                 },
2003                                                 Err(None) if is_mpp => unreachable!("We already checked for channel existence, we can't fail here!"),
2004                                                 Err(None) => {
2005                                                         log_warn!(self.logger, "Channel we expected to claim an HTLC from was closed.");
2006                                                 },
2007                                                 Ok(()) => claimed_any_htlcs = true,
2008                                         }
2009                                 }
2010                         }
2011
2012                         // Now that we've done the entire above loop in one lock, we can handle any errors
2013                         // which were generated.
2014                         channel_state.take();
2015
2016                         for (their_node_id, err) in errs.drain(..) {
2017                                 let res: Result<(), _> = Err(err);
2018                                 let _ = handle_error!(self, res, their_node_id);
2019                         }
2020
2021                         claimed_any_htlcs
2022                 } else { false }
2023         }
2024
2025         fn claim_funds_from_hop(&self, channel_state_lock: &mut MutexGuard<ChannelHolder<ChanSigner>>, prev_hop: HTLCPreviousHopData, payment_preimage: PaymentPreimage) -> Result<(), Option<(PublicKey, MsgHandleErrInternal)>> {
2026                 //TODO: Delay the claimed_funds relaying just like we do outbound relay!
2027                 let channel_state = &mut **channel_state_lock;
2028                 let chan_id = match channel_state.short_to_id.get(&prev_hop.short_channel_id) {
2029                         Some(chan_id) => chan_id.clone(),
2030                         None => {
2031                                 return Err(None)
2032                         }
2033                 };
2034
2035                 if let hash_map::Entry::Occupied(mut chan) = channel_state.by_id.entry(chan_id) {
2036                         let was_frozen_for_monitor = chan.get().is_awaiting_monitor_update();
2037                         match chan.get_mut().get_update_fulfill_htlc_and_commit(prev_hop.htlc_id, payment_preimage, &self.logger) {
2038                                 Ok((msgs, monitor_option)) => {
2039                                         if let Some(monitor_update) = monitor_option {
2040                                                 if let Err(e) = self.monitor.update_monitor(chan.get().get_funding_txo().unwrap(), monitor_update) {
2041                                                         if was_frozen_for_monitor {
2042                                                                 assert!(msgs.is_none());
2043                                                         } else {
2044                                                                 return Err(Some((chan.get().get_their_node_id(), handle_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::CommitmentFirst, false, msgs.is_some()).unwrap_err())));
2045                                                         }
2046                                                 }
2047                                         }
2048                                         if let Some((msg, commitment_signed)) = msgs {
2049                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
2050                                                         node_id: chan.get().get_their_node_id(),
2051                                                         updates: msgs::CommitmentUpdate {
2052                                                                 update_add_htlcs: Vec::new(),
2053                                                                 update_fulfill_htlcs: vec![msg],
2054                                                                 update_fail_htlcs: Vec::new(),
2055                                                                 update_fail_malformed_htlcs: Vec::new(),
2056                                                                 update_fee: None,
2057                                                                 commitment_signed,
2058                                                         }
2059                                                 });
2060                                         }
2061                                         return Ok(())
2062                                 },
2063                                 Err(e) => {
2064                                         // TODO: Do something with e?
2065                                         // This should only occur if we are claiming an HTLC at the same time as the
2066                                         // HTLC is being failed (eg because a block is being connected and this caused
2067                                         // an HTLC to time out). This should, of course, only occur if the user is the
2068                                         // one doing the claiming (as it being a part of a peer claim would imply we're
2069                                         // about to lose funds) and only if the lock in claim_funds was dropped as a
2070                                         // previous HTLC was failed (thus not for an MPP payment).
2071                                         debug_assert!(false, "This shouldn't be reachable except in absurdly rare cases between monitor updates and HTLC timeouts: {:?}", e);
2072                                         return Err(None)
2073                                 },
2074                         }
2075                 } else { unreachable!(); }
2076         }
2077
2078         fn claim_funds_internal(&self, mut channel_state_lock: MutexGuard<ChannelHolder<ChanSigner>>, source: HTLCSource, payment_preimage: PaymentPreimage) {
2079                 match source {
2080                         HTLCSource::OutboundRoute { .. } => {
2081                                 mem::drop(channel_state_lock);
2082                                 let mut pending_events = self.pending_events.lock().unwrap();
2083                                 pending_events.push(events::Event::PaymentSent {
2084                                         payment_preimage
2085                                 });
2086                         },
2087                         HTLCSource::PreviousHopData(hop_data) => {
2088                                 if let Err((their_node_id, err)) = match self.claim_funds_from_hop(&mut channel_state_lock, hop_data, payment_preimage) {
2089                                         Ok(()) => Ok(()),
2090                                         Err(None) => {
2091                                                 // TODO: There is probably a channel monitor somewhere that needs to
2092                                                 // learn the preimage as the channel already hit the chain and that's
2093                                                 // why it's missing.
2094                                                 Ok(())
2095                                         },
2096                                         Err(Some(res)) => Err(res),
2097                                 } {
2098                                         mem::drop(channel_state_lock);
2099                                         let res: Result<(), _> = Err(err);
2100                                         let _ = handle_error!(self, res, their_node_id);
2101                                 }
2102                         },
2103                 }
2104         }
2105
2106         /// Gets the node_id held by this ChannelManager
2107         pub fn get_our_node_id(&self) -> PublicKey {
2108                 PublicKey::from_secret_key(&self.secp_ctx, &self.our_network_key)
2109         }
2110
2111         /// Restores a single, given channel to normal operation after a
2112         /// ChannelMonitorUpdateErr::TemporaryFailure was returned from a channel monitor update
2113         /// operation.
2114         ///
2115         /// All ChannelMonitor updates up to and including highest_applied_update_id must have been
2116         /// fully committed in every copy of the given channels' ChannelMonitors.
2117         ///
2118         /// Note that there is no effect to calling with a highest_applied_update_id other than the
2119         /// current latest ChannelMonitorUpdate and one call to this function after multiple
2120         /// ChannelMonitorUpdateErr::TemporaryFailures is fine. The highest_applied_update_id field
2121         /// exists largely only to prevent races between this and concurrent update_monitor calls.
2122         ///
2123         /// Thus, the anticipated use is, at a high level:
2124         ///  1) You register a ManyChannelMonitor with this ChannelManager,
2125         ///  2) it stores each update to disk, and begins updating any remote (eg watchtower) copies of
2126         ///     said ChannelMonitors as it can, returning ChannelMonitorUpdateErr::TemporaryFailures
2127         ///     any time it cannot do so instantly,
2128         ///  3) update(s) are applied to each remote copy of a ChannelMonitor,
2129         ///  4) once all remote copies are updated, you call this function with the update_id that
2130         ///     completed, and once it is the latest the Channel will be re-enabled.
2131         pub fn channel_monitor_updated(&self, funding_txo: &OutPoint, highest_applied_update_id: u64) {
2132                 let _ = self.total_consistency_lock.read().unwrap();
2133
2134                 let mut close_results = Vec::new();
2135                 let mut htlc_forwards = Vec::new();
2136                 let mut htlc_failures = Vec::new();
2137                 let mut pending_events = Vec::new();
2138
2139                 {
2140                         let mut channel_lock = self.channel_state.lock().unwrap();
2141                         let channel_state = &mut *channel_lock;
2142                         let short_to_id = &mut channel_state.short_to_id;
2143                         let pending_msg_events = &mut channel_state.pending_msg_events;
2144                         let channel = match channel_state.by_id.get_mut(&funding_txo.to_channel_id()) {
2145                                 Some(chan) => chan,
2146                                 None => return,
2147                         };
2148                         if !channel.is_awaiting_monitor_update() || channel.get_latest_monitor_update_id() != highest_applied_update_id {
2149                                 return;
2150                         }
2151
2152                         let (raa, commitment_update, order, pending_forwards, mut pending_failures, needs_broadcast_safe, funding_locked) = channel.monitor_updating_restored(&self.logger);
2153                         if !pending_forwards.is_empty() {
2154                                 htlc_forwards.push((channel.get_short_channel_id().expect("We can't have pending forwards before funding confirmation"), pending_forwards));
2155                         }
2156                         htlc_failures.append(&mut pending_failures);
2157
2158                         macro_rules! handle_cs { () => {
2159                                 if let Some(update) = commitment_update {
2160                                         pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
2161                                                 node_id: channel.get_their_node_id(),
2162                                                 updates: update,
2163                                         });
2164                                 }
2165                         } }
2166                         macro_rules! handle_raa { () => {
2167                                 if let Some(revoke_and_ack) = raa {
2168                                         pending_msg_events.push(events::MessageSendEvent::SendRevokeAndACK {
2169                                                 node_id: channel.get_their_node_id(),
2170                                                 msg: revoke_and_ack,
2171                                         });
2172                                 }
2173                         } }
2174                         match order {
2175                                 RAACommitmentOrder::CommitmentFirst => {
2176                                         handle_cs!();
2177                                         handle_raa!();
2178                                 },
2179                                 RAACommitmentOrder::RevokeAndACKFirst => {
2180                                         handle_raa!();
2181                                         handle_cs!();
2182                                 },
2183                         }
2184                         if needs_broadcast_safe {
2185                                 pending_events.push(events::Event::FundingBroadcastSafe {
2186                                         funding_txo: channel.get_funding_txo().unwrap(),
2187                                         user_channel_id: channel.get_user_id(),
2188                                 });
2189                         }
2190                         if let Some(msg) = funding_locked {
2191                                 pending_msg_events.push(events::MessageSendEvent::SendFundingLocked {
2192                                         node_id: channel.get_their_node_id(),
2193                                         msg,
2194                                 });
2195                                 if let Some(announcement_sigs) = self.get_announcement_sigs(channel) {
2196                                         pending_msg_events.push(events::MessageSendEvent::SendAnnouncementSignatures {
2197                                                 node_id: channel.get_their_node_id(),
2198                                                 msg: announcement_sigs,
2199                                         });
2200                                 }
2201                                 short_to_id.insert(channel.get_short_channel_id().unwrap(), channel.channel_id());
2202                         }
2203                 }
2204
2205                 self.pending_events.lock().unwrap().append(&mut pending_events);
2206
2207                 for failure in htlc_failures.drain(..) {
2208                         self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), failure.0, &failure.1, failure.2);
2209                 }
2210                 self.forward_htlcs(&mut htlc_forwards[..]);
2211
2212                 for res in close_results.drain(..) {
2213                         self.finish_force_close_channel(res);
2214                 }
2215         }
2216
2217         fn internal_open_channel(&self, their_node_id: &PublicKey, their_features: InitFeatures, msg: &msgs::OpenChannel) -> Result<(), MsgHandleErrInternal> {
2218                 if msg.chain_hash != self.genesis_hash {
2219                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Unknown genesis block hash", msg.temporary_channel_id.clone()));
2220                 }
2221
2222                 let channel = Channel::new_from_req(&self.fee_estimator, &self.keys_manager, their_node_id.clone(), their_features, msg, 0, &self.default_configuration)
2223                         .map_err(|e| MsgHandleErrInternal::from_chan_no_close(e, msg.temporary_channel_id))?;
2224                 let mut channel_state_lock = self.channel_state.lock().unwrap();
2225                 let channel_state = &mut *channel_state_lock;
2226                 match channel_state.by_id.entry(channel.channel_id()) {
2227                         hash_map::Entry::Occupied(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("temporary_channel_id collision!", msg.temporary_channel_id.clone())),
2228                         hash_map::Entry::Vacant(entry) => {
2229                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendAcceptChannel {
2230                                         node_id: their_node_id.clone(),
2231                                         msg: channel.get_accept_channel(),
2232                                 });
2233                                 entry.insert(channel);
2234                         }
2235                 }
2236                 Ok(())
2237         }
2238
2239         fn internal_accept_channel(&self, their_node_id: &PublicKey, their_features: InitFeatures, msg: &msgs::AcceptChannel) -> Result<(), MsgHandleErrInternal> {
2240                 let (value, output_script, user_id) = {
2241                         let mut channel_lock = self.channel_state.lock().unwrap();
2242                         let channel_state = &mut *channel_lock;
2243                         match channel_state.by_id.entry(msg.temporary_channel_id) {
2244                                 hash_map::Entry::Occupied(mut chan) => {
2245                                         if chan.get().get_their_node_id() != *their_node_id {
2246                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.temporary_channel_id));
2247                                         }
2248                                         try_chan_entry!(self, chan.get_mut().accept_channel(&msg, &self.default_configuration, their_features), channel_state, chan);
2249                                         (chan.get().get_value_satoshis(), chan.get().get_funding_redeemscript().to_v0_p2wsh(), chan.get().get_user_id())
2250                                 },
2251                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.temporary_channel_id))
2252                         }
2253                 };
2254                 let mut pending_events = self.pending_events.lock().unwrap();
2255                 pending_events.push(events::Event::FundingGenerationReady {
2256                         temporary_channel_id: msg.temporary_channel_id,
2257                         channel_value_satoshis: value,
2258                         output_script: output_script,
2259                         user_channel_id: user_id,
2260                 });
2261                 Ok(())
2262         }
2263
2264         fn internal_funding_created(&self, their_node_id: &PublicKey, msg: &msgs::FundingCreated) -> Result<(), MsgHandleErrInternal> {
2265                 let ((funding_msg, monitor_update), mut chan) = {
2266                         let mut channel_lock = self.channel_state.lock().unwrap();
2267                         let channel_state = &mut *channel_lock;
2268                         match channel_state.by_id.entry(msg.temporary_channel_id.clone()) {
2269                                 hash_map::Entry::Occupied(mut chan) => {
2270                                         if chan.get().get_their_node_id() != *their_node_id {
2271                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.temporary_channel_id));
2272                                         }
2273                                         (try_chan_entry!(self, chan.get_mut().funding_created(msg, &self.logger), channel_state, chan), chan.remove())
2274                                 },
2275                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.temporary_channel_id))
2276                         }
2277                 };
2278                 // Because we have exclusive ownership of the channel here we can release the channel_state
2279                 // lock before add_monitor
2280                 if let Err(e) = self.monitor.add_monitor(monitor_update.get_funding_txo(), monitor_update) {
2281                         match e {
2282                                 ChannelMonitorUpdateErr::PermanentFailure => {
2283                                         // Note that we reply with the new channel_id in error messages if we gave up on the
2284                                         // channel, not the temporary_channel_id. This is compatible with ourselves, but the
2285                                         // spec is somewhat ambiguous here. Not a huge deal since we'll send error messages for
2286                                         // any messages referencing a previously-closed channel anyway.
2287                                         return Err(MsgHandleErrInternal::from_finish_shutdown("ChannelMonitor storage failure", funding_msg.channel_id, chan.force_shutdown(true), None));
2288                                 },
2289                                 ChannelMonitorUpdateErr::TemporaryFailure => {
2290                                         // There's no problem signing a counterparty's funding transaction if our monitor
2291                                         // hasn't persisted to disk yet - we can't lose money on a transaction that we haven't
2292                                         // accepted payment from yet. We do, however, need to wait to send our funding_locked
2293                                         // until we have persisted our monitor.
2294                                         chan.monitor_update_failed(false, false, Vec::new(), Vec::new());
2295                                 },
2296                         }
2297                 }
2298                 let mut channel_state_lock = self.channel_state.lock().unwrap();
2299                 let channel_state = &mut *channel_state_lock;
2300                 match channel_state.by_id.entry(funding_msg.channel_id) {
2301                         hash_map::Entry::Occupied(_) => {
2302                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Already had channel with the new channel_id", funding_msg.channel_id))
2303                         },
2304                         hash_map::Entry::Vacant(e) => {
2305                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendFundingSigned {
2306                                         node_id: their_node_id.clone(),
2307                                         msg: funding_msg,
2308                                 });
2309                                 e.insert(chan);
2310                         }
2311                 }
2312                 Ok(())
2313         }
2314
2315         fn internal_funding_signed(&self, their_node_id: &PublicKey, msg: &msgs::FundingSigned) -> Result<(), MsgHandleErrInternal> {
2316                 let (funding_txo, user_id) = {
2317                         let mut channel_lock = self.channel_state.lock().unwrap();
2318                         let channel_state = &mut *channel_lock;
2319                         match channel_state.by_id.entry(msg.channel_id) {
2320                                 hash_map::Entry::Occupied(mut chan) => {
2321                                         if chan.get().get_their_node_id() != *their_node_id {
2322                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2323                                         }
2324                                         let monitor = match chan.get_mut().funding_signed(&msg, &self.logger) {
2325                                                 Ok(update) => update,
2326                                                 Err(e) => try_chan_entry!(self, Err(e), channel_state, chan),
2327                                         };
2328                                         if let Err(e) = self.monitor.add_monitor(chan.get().get_funding_txo().unwrap(), monitor) {
2329                                                 return_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::RevokeAndACKFirst, false, false);
2330                                         }
2331                                         (chan.get().get_funding_txo().unwrap(), chan.get().get_user_id())
2332                                 },
2333                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2334                         }
2335                 };
2336                 let mut pending_events = self.pending_events.lock().unwrap();
2337                 pending_events.push(events::Event::FundingBroadcastSafe {
2338                         funding_txo: funding_txo,
2339                         user_channel_id: user_id,
2340                 });
2341                 Ok(())
2342         }
2343
2344         fn internal_funding_locked(&self, their_node_id: &PublicKey, msg: &msgs::FundingLocked) -> Result<(), MsgHandleErrInternal> {
2345                 let mut channel_state_lock = self.channel_state.lock().unwrap();
2346                 let channel_state = &mut *channel_state_lock;
2347                 match channel_state.by_id.entry(msg.channel_id) {
2348                         hash_map::Entry::Occupied(mut chan) => {
2349                                 if chan.get().get_their_node_id() != *their_node_id {
2350                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2351                                 }
2352                                 try_chan_entry!(self, chan.get_mut().funding_locked(&msg), channel_state, chan);
2353                                 if let Some(announcement_sigs) = self.get_announcement_sigs(chan.get()) {
2354                                         log_trace!(self.logger, "Sending announcement_signatures for {} in response to funding_locked", log_bytes!(chan.get().channel_id()));
2355                                         // If we see locking block before receiving remote funding_locked, we broadcast our
2356                                         // announcement_sigs at remote funding_locked reception. If we receive remote
2357                                         // funding_locked before seeing locking block, we broadcast our announcement_sigs at locking
2358                                         // block connection. We should guanrantee to broadcast announcement_sigs to our peer whatever
2359                                         // the order of the events but our peer may not receive it due to disconnection. The specs
2360                                         // lacking an acknowledgement for announcement_sigs we may have to re-send them at peer
2361                                         // connection in the future if simultaneous misses by both peers due to network/hardware
2362                                         // failures is an issue. Note, to achieve its goal, only one of the announcement_sigs needs
2363                                         // to be received, from then sigs are going to be flood to the whole network.
2364                                         channel_state.pending_msg_events.push(events::MessageSendEvent::SendAnnouncementSignatures {
2365                                                 node_id: their_node_id.clone(),
2366                                                 msg: announcement_sigs,
2367                                         });
2368                                 }
2369                                 Ok(())
2370                         },
2371                         hash_map::Entry::Vacant(_) => Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2372                 }
2373         }
2374
2375         fn internal_shutdown(&self, their_node_id: &PublicKey, msg: &msgs::Shutdown) -> Result<(), MsgHandleErrInternal> {
2376                 let (mut dropped_htlcs, chan_option) = {
2377                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2378                         let channel_state = &mut *channel_state_lock;
2379
2380                         match channel_state.by_id.entry(msg.channel_id.clone()) {
2381                                 hash_map::Entry::Occupied(mut chan_entry) => {
2382                                         if chan_entry.get().get_their_node_id() != *their_node_id {
2383                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2384                                         }
2385                                         let (shutdown, closing_signed, dropped_htlcs) = try_chan_entry!(self, chan_entry.get_mut().shutdown(&self.fee_estimator, &msg), channel_state, chan_entry);
2386                                         if let Some(msg) = shutdown {
2387                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendShutdown {
2388                                                         node_id: their_node_id.clone(),
2389                                                         msg,
2390                                                 });
2391                                         }
2392                                         if let Some(msg) = closing_signed {
2393                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendClosingSigned {
2394                                                         node_id: their_node_id.clone(),
2395                                                         msg,
2396                                                 });
2397                                         }
2398                                         if chan_entry.get().is_shutdown() {
2399                                                 if let Some(short_id) = chan_entry.get().get_short_channel_id() {
2400                                                         channel_state.short_to_id.remove(&short_id);
2401                                                 }
2402                                                 (dropped_htlcs, Some(chan_entry.remove_entry().1))
2403                                         } else { (dropped_htlcs, None) }
2404                                 },
2405                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2406                         }
2407                 };
2408                 for htlc_source in dropped_htlcs.drain(..) {
2409                         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() });
2410                 }
2411                 if let Some(chan) = chan_option {
2412                         if let Ok(update) = self.get_channel_update(&chan) {
2413                                 let mut channel_state = self.channel_state.lock().unwrap();
2414                                 channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
2415                                         msg: update
2416                                 });
2417                         }
2418                 }
2419                 Ok(())
2420         }
2421
2422         fn internal_closing_signed(&self, their_node_id: &PublicKey, msg: &msgs::ClosingSigned) -> Result<(), MsgHandleErrInternal> {
2423                 let (tx, chan_option) = {
2424                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2425                         let channel_state = &mut *channel_state_lock;
2426                         match channel_state.by_id.entry(msg.channel_id.clone()) {
2427                                 hash_map::Entry::Occupied(mut chan_entry) => {
2428                                         if chan_entry.get().get_their_node_id() != *their_node_id {
2429                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2430                                         }
2431                                         let (closing_signed, tx) = try_chan_entry!(self, chan_entry.get_mut().closing_signed(&self.fee_estimator, &msg), channel_state, chan_entry);
2432                                         if let Some(msg) = closing_signed {
2433                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendClosingSigned {
2434                                                         node_id: their_node_id.clone(),
2435                                                         msg,
2436                                                 });
2437                                         }
2438                                         if tx.is_some() {
2439                                                 // We're done with this channel, we've got a signed closing transaction and
2440                                                 // will send the closing_signed back to the remote peer upon return. This
2441                                                 // also implies there are no pending HTLCs left on the channel, so we can
2442                                                 // fully delete it from tracking (the channel monitor is still around to
2443                                                 // watch for old state broadcasts)!
2444                                                 if let Some(short_id) = chan_entry.get().get_short_channel_id() {
2445                                                         channel_state.short_to_id.remove(&short_id);
2446                                                 }
2447                                                 (tx, Some(chan_entry.remove_entry().1))
2448                                         } else { (tx, None) }
2449                                 },
2450                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2451                         }
2452                 };
2453                 if let Some(broadcast_tx) = tx {
2454                         log_trace!(self.logger, "Broadcast onchain {}", log_tx!(broadcast_tx));
2455                         self.tx_broadcaster.broadcast_transaction(&broadcast_tx);
2456                 }
2457                 if let Some(chan) = chan_option {
2458                         if let Ok(update) = self.get_channel_update(&chan) {
2459                                 let mut channel_state = self.channel_state.lock().unwrap();
2460                                 channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
2461                                         msg: update
2462                                 });
2463                         }
2464                 }
2465                 Ok(())
2466         }
2467
2468         fn internal_update_add_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateAddHTLC) -> Result<(), MsgHandleErrInternal> {
2469                 //TODO: BOLT 4 points out a specific attack where a peer may re-send an onion packet and
2470                 //determine the state of the payment based on our response/if we forward anything/the time
2471                 //we take to respond. We should take care to avoid allowing such an attack.
2472                 //
2473                 //TODO: There exists a further attack where a node may garble the onion data, forward it to
2474                 //us repeatedly garbled in different ways, and compare our error messages, which are
2475                 //encrypted with the same key. It's not immediately obvious how to usefully exploit that,
2476                 //but we should prevent it anyway.
2477
2478                 let (mut pending_forward_info, mut channel_state_lock) = self.decode_update_add_htlc_onion(msg);
2479                 let channel_state = &mut *channel_state_lock;
2480
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                                 if !chan.get().is_usable() {
2487                                         // If the update_add is completely bogus, the call will Err and we will close,
2488                                         // but if we've sent a shutdown and they haven't acknowledged it yet, we just
2489                                         // want to reject the new HTLC and fail it backwards instead of forwarding.
2490                                         if let PendingHTLCStatus::Forward(PendingHTLCInfo { incoming_shared_secret, .. }) = pending_forward_info {
2491                                                 let chan_update = self.get_channel_update(chan.get());
2492                                                 pending_forward_info = PendingHTLCStatus::Fail(HTLCFailureMsg::Relay(msgs::UpdateFailHTLC {
2493                                                         channel_id: msg.channel_id,
2494                                                         htlc_id: msg.htlc_id,
2495                                                         reason: if let Ok(update) = chan_update {
2496                                                                 // TODO: Note that |20 is defined as "channel FROM the processing
2497                                                                 // node has been disabled" (emphasis mine), which seems to imply
2498                                                                 // that we can't return |20 for an inbound channel being disabled.
2499                                                                 // This probably needs a spec update but should definitely be
2500                                                                 // allowed.
2501                                                                 onion_utils::build_first_hop_failure_packet(&incoming_shared_secret, 0x1000|20, &{
2502                                                                         let mut res = Vec::with_capacity(8 + 128);
2503                                                                         res.extend_from_slice(&byte_utils::be16_to_array(update.contents.flags));
2504                                                                         res.extend_from_slice(&update.encode_with_len()[..]);
2505                                                                         res
2506                                                                 }[..])
2507                                                         } else {
2508                                                                 // This can only happen if the channel isn't in the fully-funded
2509                                                                 // state yet, implying our counterparty is trying to route payments
2510                                                                 // over the channel back to themselves (cause no one else should
2511                                                                 // know the short_id is a lightning channel yet). We should have no
2512                                                                 // problem just calling this unknown_next_peer
2513                                                                 onion_utils::build_first_hop_failure_packet(&incoming_shared_secret, 0x4000|10, &[])
2514                                                         },
2515                                                 }));
2516                                         }
2517                                 }
2518                                 try_chan_entry!(self, chan.get_mut().update_add_htlc(&msg, pending_forward_info), channel_state, chan);
2519                         },
2520                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2521                 }
2522                 Ok(())
2523         }
2524
2525         fn internal_update_fulfill_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFulfillHTLC) -> Result<(), MsgHandleErrInternal> {
2526                 let mut channel_lock = self.channel_state.lock().unwrap();
2527                 let htlc_source = {
2528                         let channel_state = &mut *channel_lock;
2529                         match channel_state.by_id.entry(msg.channel_id) {
2530                                 hash_map::Entry::Occupied(mut chan) => {
2531                                         if chan.get().get_their_node_id() != *their_node_id {
2532                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2533                                         }
2534                                         try_chan_entry!(self, chan.get_mut().update_fulfill_htlc(&msg), channel_state, chan)
2535                                 },
2536                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2537                         }
2538                 };
2539                 self.claim_funds_internal(channel_lock, htlc_source, msg.payment_preimage.clone());
2540                 Ok(())
2541         }
2542
2543         fn internal_update_fail_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFailHTLC) -> Result<(), MsgHandleErrInternal> {
2544                 let mut channel_lock = self.channel_state.lock().unwrap();
2545                 let channel_state = &mut *channel_lock;
2546                 match channel_state.by_id.entry(msg.channel_id) {
2547                         hash_map::Entry::Occupied(mut chan) => {
2548                                 if chan.get().get_their_node_id() != *their_node_id {
2549                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2550                                 }
2551                                 try_chan_entry!(self, chan.get_mut().update_fail_htlc(&msg, HTLCFailReason::LightningError { err: msg.reason.clone() }), channel_state, chan);
2552                         },
2553                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2554                 }
2555                 Ok(())
2556         }
2557
2558         fn internal_update_fail_malformed_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFailMalformedHTLC) -> Result<(), MsgHandleErrInternal> {
2559                 let mut channel_lock = self.channel_state.lock().unwrap();
2560                 let channel_state = &mut *channel_lock;
2561                 match channel_state.by_id.entry(msg.channel_id) {
2562                         hash_map::Entry::Occupied(mut chan) => {
2563                                 if chan.get().get_their_node_id() != *their_node_id {
2564                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2565                                 }
2566                                 if (msg.failure_code & 0x8000) == 0 {
2567                                         let chan_err: ChannelError = ChannelError::Close("Got update_fail_malformed_htlc with BADONION not set");
2568                                         try_chan_entry!(self, Err(chan_err), channel_state, chan);
2569                                 }
2570                                 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);
2571                                 Ok(())
2572                         },
2573                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2574                 }
2575         }
2576
2577         fn internal_commitment_signed(&self, their_node_id: &PublicKey, msg: &msgs::CommitmentSigned) -> Result<(), MsgHandleErrInternal> {
2578                 let mut channel_state_lock = self.channel_state.lock().unwrap();
2579                 let channel_state = &mut *channel_state_lock;
2580                 match channel_state.by_id.entry(msg.channel_id) {
2581                         hash_map::Entry::Occupied(mut chan) => {
2582                                 if chan.get().get_their_node_id() != *their_node_id {
2583                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2584                                 }
2585                                 let (revoke_and_ack, commitment_signed, closing_signed, monitor_update) =
2586                                         match chan.get_mut().commitment_signed(&msg, &self.fee_estimator, &self.logger) {
2587                                                 Err((None, e)) => try_chan_entry!(self, Err(e), channel_state, chan),
2588                                                 Err((Some(update), e)) => {
2589                                                         assert!(chan.get().is_awaiting_monitor_update());
2590                                                         let _ = self.monitor.update_monitor(chan.get().get_funding_txo().unwrap(), update);
2591                                                         try_chan_entry!(self, Err(e), channel_state, chan);
2592                                                         unreachable!();
2593                                                 },
2594                                                 Ok(res) => res
2595                                         };
2596                                 if let Err(e) = self.monitor.update_monitor(chan.get().get_funding_txo().unwrap(), monitor_update) {
2597                                         return_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::RevokeAndACKFirst, true, commitment_signed.is_some());
2598                                         //TODO: Rebroadcast closing_signed if present on monitor update restoration
2599                                 }
2600                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendRevokeAndACK {
2601                                         node_id: their_node_id.clone(),
2602                                         msg: revoke_and_ack,
2603                                 });
2604                                 if let Some(msg) = commitment_signed {
2605                                         channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
2606                                                 node_id: their_node_id.clone(),
2607                                                 updates: msgs::CommitmentUpdate {
2608                                                         update_add_htlcs: Vec::new(),
2609                                                         update_fulfill_htlcs: Vec::new(),
2610                                                         update_fail_htlcs: Vec::new(),
2611                                                         update_fail_malformed_htlcs: Vec::new(),
2612                                                         update_fee: None,
2613                                                         commitment_signed: msg,
2614                                                 },
2615                                         });
2616                                 }
2617                                 if let Some(msg) = closing_signed {
2618                                         channel_state.pending_msg_events.push(events::MessageSendEvent::SendClosingSigned {
2619                                                 node_id: their_node_id.clone(),
2620                                                 msg,
2621                                         });
2622                                 }
2623                                 Ok(())
2624                         },
2625                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2626                 }
2627         }
2628
2629         #[inline]
2630         fn forward_htlcs(&self, per_source_pending_forwards: &mut [(u64, Vec<(PendingHTLCInfo, u64)>)]) {
2631                 for &mut (prev_short_channel_id, ref mut pending_forwards) in per_source_pending_forwards {
2632                         let mut forward_event = None;
2633                         if !pending_forwards.is_empty() {
2634                                 let mut channel_state = self.channel_state.lock().unwrap();
2635                                 if channel_state.forward_htlcs.is_empty() {
2636                                         forward_event = Some(Duration::from_millis(MIN_HTLC_RELAY_HOLDING_CELL_MILLIS))
2637                                 }
2638                                 for (forward_info, prev_htlc_id) in pending_forwards.drain(..) {
2639                                         match channel_state.forward_htlcs.entry(match forward_info.routing {
2640                                                         PendingHTLCRouting::Forward { short_channel_id, .. } => short_channel_id,
2641                                                         PendingHTLCRouting::Receive { .. } => 0,
2642                                         }) {
2643                                                 hash_map::Entry::Occupied(mut entry) => {
2644                                                         entry.get_mut().push(HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info });
2645                                                 },
2646                                                 hash_map::Entry::Vacant(entry) => {
2647                                                         entry.insert(vec!(HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info }));
2648                                                 }
2649                                         }
2650                                 }
2651                         }
2652                         match forward_event {
2653                                 Some(time) => {
2654                                         let mut pending_events = self.pending_events.lock().unwrap();
2655                                         pending_events.push(events::Event::PendingHTLCsForwardable {
2656                                                 time_forwardable: time
2657                                         });
2658                                 }
2659                                 None => {},
2660                         }
2661                 }
2662         }
2663
2664         fn internal_revoke_and_ack(&self, their_node_id: &PublicKey, msg: &msgs::RevokeAndACK) -> Result<(), MsgHandleErrInternal> {
2665                 let (pending_forwards, mut pending_failures, short_channel_id) = {
2666                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2667                         let channel_state = &mut *channel_state_lock;
2668                         match channel_state.by_id.entry(msg.channel_id) {
2669                                 hash_map::Entry::Occupied(mut chan) => {
2670                                         if chan.get().get_their_node_id() != *their_node_id {
2671                                                 return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2672                                         }
2673                                         let was_frozen_for_monitor = chan.get().is_awaiting_monitor_update();
2674                                         let (commitment_update, pending_forwards, pending_failures, closing_signed, monitor_update) =
2675                                                 try_chan_entry!(self, chan.get_mut().revoke_and_ack(&msg, &self.fee_estimator, &self.logger), channel_state, chan);
2676                                         if let Err(e) = self.monitor.update_monitor(chan.get().get_funding_txo().unwrap(), monitor_update) {
2677                                                 if was_frozen_for_monitor {
2678                                                         assert!(commitment_update.is_none() && closing_signed.is_none() && pending_forwards.is_empty() && pending_failures.is_empty());
2679                                                         return Err(MsgHandleErrInternal::ignore_no_close("Previous monitor update failure prevented responses to RAA"));
2680                                                 } else {
2681                                                         return_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::CommitmentFirst, false, commitment_update.is_some(), pending_forwards, pending_failures);
2682                                                 }
2683                                         }
2684                                         if let Some(updates) = commitment_update {
2685                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
2686                                                         node_id: their_node_id.clone(),
2687                                                         updates,
2688                                                 });
2689                                         }
2690                                         if let Some(msg) = closing_signed {
2691                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendClosingSigned {
2692                                                         node_id: their_node_id.clone(),
2693                                                         msg,
2694                                                 });
2695                                         }
2696                                         (pending_forwards, pending_failures, chan.get().get_short_channel_id().expect("RAA should only work on a short-id-available channel"))
2697                                 },
2698                                 hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2699                         }
2700                 };
2701                 for failure in pending_failures.drain(..) {
2702                         self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), failure.0, &failure.1, failure.2);
2703                 }
2704                 self.forward_htlcs(&mut [(short_channel_id, pending_forwards)]);
2705
2706                 Ok(())
2707         }
2708
2709         fn internal_update_fee(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFee) -> Result<(), MsgHandleErrInternal> {
2710                 let mut channel_lock = self.channel_state.lock().unwrap();
2711                 let channel_state = &mut *channel_lock;
2712                 match channel_state.by_id.entry(msg.channel_id) {
2713                         hash_map::Entry::Occupied(mut chan) => {
2714                                 if chan.get().get_their_node_id() != *their_node_id {
2715                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2716                                 }
2717                                 try_chan_entry!(self, chan.get_mut().update_fee(&self.fee_estimator, &msg), channel_state, chan);
2718                         },
2719                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2720                 }
2721                 Ok(())
2722         }
2723
2724         fn internal_announcement_signatures(&self, their_node_id: &PublicKey, msg: &msgs::AnnouncementSignatures) -> Result<(), MsgHandleErrInternal> {
2725                 let mut channel_state_lock = self.channel_state.lock().unwrap();
2726                 let channel_state = &mut *channel_state_lock;
2727
2728                 match channel_state.by_id.entry(msg.channel_id) {
2729                         hash_map::Entry::Occupied(mut chan) => {
2730                                 if chan.get().get_their_node_id() != *their_node_id {
2731                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2732                                 }
2733                                 if !chan.get().is_usable() {
2734                                         return Err(MsgHandleErrInternal::from_no_close(LightningError{err: "Got an announcement_signatures before we were ready for it", action: msgs::ErrorAction::IgnoreError}));
2735                                 }
2736
2737                                 let our_node_id = self.get_our_node_id();
2738                                 let (announcement, our_bitcoin_sig) =
2739                                         try_chan_entry!(self, chan.get_mut().get_channel_announcement(our_node_id.clone(), self.genesis_hash.clone()), channel_state, chan);
2740
2741                                 let were_node_one = announcement.node_id_1 == our_node_id;
2742                                 let msghash = hash_to_message!(&Sha256dHash::hash(&announcement.encode()[..])[..]);
2743                                 if self.secp_ctx.verify(&msghash, &msg.node_signature, if were_node_one { &announcement.node_id_2 } else { &announcement.node_id_1 }).is_err() ||
2744                                                 self.secp_ctx.verify(&msghash, &msg.bitcoin_signature, if were_node_one { &announcement.bitcoin_key_2 } else { &announcement.bitcoin_key_1 }).is_err() {
2745                                         let chan_err: ChannelError = ChannelError::Close("Bad announcement_signatures node_signature");
2746                                         try_chan_entry!(self, Err(chan_err), channel_state, chan);
2747                                 }
2748
2749                                 let our_node_sig = self.secp_ctx.sign(&msghash, &self.our_network_key);
2750
2751                                 channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelAnnouncement {
2752                                         msg: msgs::ChannelAnnouncement {
2753                                                 node_signature_1: if were_node_one { our_node_sig } else { msg.node_signature },
2754                                                 node_signature_2: if were_node_one { msg.node_signature } else { our_node_sig },
2755                                                 bitcoin_signature_1: if were_node_one { our_bitcoin_sig } else { msg.bitcoin_signature },
2756                                                 bitcoin_signature_2: if were_node_one { msg.bitcoin_signature } else { our_bitcoin_sig },
2757                                                 contents: announcement,
2758                                         },
2759                                         update_msg: self.get_channel_update(chan.get()).unwrap(), // can only fail if we're not in a ready state
2760                                 });
2761                         },
2762                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2763                 }
2764                 Ok(())
2765         }
2766
2767         fn internal_channel_reestablish(&self, their_node_id: &PublicKey, msg: &msgs::ChannelReestablish) -> Result<(), MsgHandleErrInternal> {
2768                 let mut channel_state_lock = self.channel_state.lock().unwrap();
2769                 let channel_state = &mut *channel_state_lock;
2770
2771                 match channel_state.by_id.entry(msg.channel_id) {
2772                         hash_map::Entry::Occupied(mut chan) => {
2773                                 if chan.get().get_their_node_id() != *their_node_id {
2774                                         return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
2775                                 }
2776                                 let (funding_locked, revoke_and_ack, commitment_update, monitor_update_opt, mut order, shutdown) =
2777                                         try_chan_entry!(self, chan.get_mut().channel_reestablish(msg, &self.logger), channel_state, chan);
2778                                 if let Some(monitor_update) = monitor_update_opt {
2779                                         if let Err(e) = self.monitor.update_monitor(chan.get().get_funding_txo().unwrap(), monitor_update) {
2780                                                 // channel_reestablish doesn't guarantee the order it returns is sensical
2781                                                 // for the messages it returns, but if we're setting what messages to
2782                                                 // re-transmit on monitor update success, we need to make sure it is sane.
2783                                                 if revoke_and_ack.is_none() {
2784                                                         order = RAACommitmentOrder::CommitmentFirst;
2785                                                 }
2786                                                 if commitment_update.is_none() {
2787                                                         order = RAACommitmentOrder::RevokeAndACKFirst;
2788                                                 }
2789                                                 return_monitor_err!(self, e, channel_state, chan, order, revoke_and_ack.is_some(), commitment_update.is_some());
2790                                                 //TODO: Resend the funding_locked if needed once we get the monitor running again
2791                                         }
2792                                 }
2793                                 if let Some(msg) = funding_locked {
2794                                         channel_state.pending_msg_events.push(events::MessageSendEvent::SendFundingLocked {
2795                                                 node_id: their_node_id.clone(),
2796                                                 msg
2797                                         });
2798                                 }
2799                                 macro_rules! send_raa { () => {
2800                                         if let Some(msg) = revoke_and_ack {
2801                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::SendRevokeAndACK {
2802                                                         node_id: their_node_id.clone(),
2803                                                         msg
2804                                                 });
2805                                         }
2806                                 } }
2807                                 macro_rules! send_cu { () => {
2808                                         if let Some(updates) = commitment_update {
2809                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
2810                                                         node_id: their_node_id.clone(),
2811                                                         updates
2812                                                 });
2813                                         }
2814                                 } }
2815                                 match order {
2816                                         RAACommitmentOrder::RevokeAndACKFirst => {
2817                                                 send_raa!();
2818                                                 send_cu!();
2819                                         },
2820                                         RAACommitmentOrder::CommitmentFirst => {
2821                                                 send_cu!();
2822                                                 send_raa!();
2823                                         },
2824                                 }
2825                                 if let Some(msg) = shutdown {
2826                                         channel_state.pending_msg_events.push(events::MessageSendEvent::SendShutdown {
2827                                                 node_id: their_node_id.clone(),
2828                                                 msg,
2829                                         });
2830                                 }
2831                                 Ok(())
2832                         },
2833                         hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
2834                 }
2835         }
2836
2837         /// Begin Update fee process. Allowed only on an outbound channel.
2838         /// If successful, will generate a UpdateHTLCs event, so you should probably poll
2839         /// PeerManager::process_events afterwards.
2840         /// Note: This API is likely to change!
2841         #[doc(hidden)]
2842         pub fn update_fee(&self, channel_id: [u8;32], feerate_per_kw: u64) -> Result<(), APIError> {
2843                 let _ = self.total_consistency_lock.read().unwrap();
2844                 let their_node_id;
2845                 let err: Result<(), _> = loop {
2846                         let mut channel_state_lock = self.channel_state.lock().unwrap();
2847                         let channel_state = &mut *channel_state_lock;
2848
2849                         match channel_state.by_id.entry(channel_id) {
2850                                 hash_map::Entry::Vacant(_) => return Err(APIError::APIMisuseError{err: "Failed to find corresponding channel"}),
2851                                 hash_map::Entry::Occupied(mut chan) => {
2852                                         if !chan.get().is_outbound() {
2853                                                 return Err(APIError::APIMisuseError{err: "update_fee cannot be sent for an inbound channel"});
2854                                         }
2855                                         if chan.get().is_awaiting_monitor_update() {
2856                                                 return Err(APIError::MonitorUpdateFailed);
2857                                         }
2858                                         if !chan.get().is_live() {
2859                                                 return Err(APIError::ChannelUnavailable{err: "Channel is either not yet fully established or peer is currently disconnected"});
2860                                         }
2861                                         their_node_id = chan.get().get_their_node_id();
2862                                         if let Some((update_fee, commitment_signed, monitor_update)) =
2863                                                         break_chan_entry!(self, chan.get_mut().send_update_fee_and_commit(feerate_per_kw, &self.logger), channel_state, chan)
2864                                         {
2865                                                 if let Err(_e) = self.monitor.update_monitor(chan.get().get_funding_txo().unwrap(), monitor_update) {
2866                                                         unimplemented!();
2867                                                 }
2868                                                 channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
2869                                                         node_id: chan.get().get_their_node_id(),
2870                                                         updates: msgs::CommitmentUpdate {
2871                                                                 update_add_htlcs: Vec::new(),
2872                                                                 update_fulfill_htlcs: Vec::new(),
2873                                                                 update_fail_htlcs: Vec::new(),
2874                                                                 update_fail_malformed_htlcs: Vec::new(),
2875                                                                 update_fee: Some(update_fee),
2876                                                                 commitment_signed,
2877                                                         },
2878                                                 });
2879                                         }
2880                                 },
2881                         }
2882                         return Ok(())
2883                 };
2884
2885                 match handle_error!(self, err, their_node_id) {
2886                         Ok(_) => unreachable!(),
2887                         Err(e) => { Err(APIError::APIMisuseError { err: e.err })}
2888                 }
2889         }
2890 }
2891
2892 impl<ChanSigner: ChannelKeys, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> events::MessageSendEventsProvider for ChannelManager<ChanSigner, M, T, K, F, L>
2893         where M::Target: ManyChannelMonitor<ChanSigner>,
2894         T::Target: BroadcasterInterface,
2895         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
2896         F::Target: FeeEstimator,
2897                                 L::Target: Logger,
2898 {
2899         fn get_and_clear_pending_msg_events(&self) -> Vec<events::MessageSendEvent> {
2900                 // TODO: Event release to users and serialization is currently race-y: it's very easy for a
2901                 // user to serialize a ChannelManager with pending events in it and lose those events on
2902                 // restart. This is doubly true for the fail/fulfill-backs from monitor events!
2903                 {
2904                         //TODO: This behavior should be documented.
2905                         for htlc_update in self.monitor.get_and_clear_pending_htlcs_updated() {
2906                                 if let Some(preimage) = htlc_update.payment_preimage {
2907                                         log_trace!(self.logger, "Claiming HTLC with preimage {} from our monitor", log_bytes!(preimage.0));
2908                                         self.claim_funds_internal(self.channel_state.lock().unwrap(), htlc_update.source, preimage);
2909                                 } else {
2910                                         log_trace!(self.logger, "Failing HTLC with hash {} from our monitor", log_bytes!(htlc_update.payment_hash.0));
2911                                         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() });
2912                                 }
2913                         }
2914                 }
2915
2916                 let mut ret = Vec::new();
2917                 let mut channel_state = self.channel_state.lock().unwrap();
2918                 mem::swap(&mut ret, &mut channel_state.pending_msg_events);
2919                 ret
2920         }
2921 }
2922
2923 impl<ChanSigner: ChannelKeys, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> events::EventsProvider for ChannelManager<ChanSigner, M, T, K, F, L>
2924         where M::Target: ManyChannelMonitor<ChanSigner>,
2925         T::Target: BroadcasterInterface,
2926         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
2927         F::Target: FeeEstimator,
2928                                 L::Target: Logger,
2929 {
2930         fn get_and_clear_pending_events(&self) -> Vec<events::Event> {
2931                 // TODO: Event release to users and serialization is currently race-y: it's very easy for a
2932                 // user to serialize a ChannelManager with pending events in it and lose those events on
2933                 // restart. This is doubly true for the fail/fulfill-backs from monitor events!
2934                 {
2935                         //TODO: This behavior should be documented.
2936                         for htlc_update in self.monitor.get_and_clear_pending_htlcs_updated() {
2937                                 if let Some(preimage) = htlc_update.payment_preimage {
2938                                         log_trace!(self.logger, "Claiming HTLC with preimage {} from our monitor", log_bytes!(preimage.0));
2939                                         self.claim_funds_internal(self.channel_state.lock().unwrap(), htlc_update.source, preimage);
2940                                 } else {
2941                                         log_trace!(self.logger, "Failing HTLC with hash {} from our monitor", log_bytes!(htlc_update.payment_hash.0));
2942                                         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() });
2943                                 }
2944                         }
2945                 }
2946
2947                 let mut ret = Vec::new();
2948                 let mut pending_events = self.pending_events.lock().unwrap();
2949                 mem::swap(&mut ret, &mut *pending_events);
2950                 ret
2951         }
2952 }
2953
2954 impl<ChanSigner: ChannelKeys, M: Deref + Sync + Send, T: Deref + Sync + Send, K: Deref + Sync + Send, F: Deref + Sync + Send, L: Deref + Sync + Send>
2955         ChainListener for ChannelManager<ChanSigner, M, T, K, F, L>
2956         where M::Target: ManyChannelMonitor<ChanSigner>,
2957         T::Target: BroadcasterInterface,
2958         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
2959         F::Target: FeeEstimator,
2960                                 L::Target: Logger,
2961 {
2962         fn block_connected(&self, header: &BlockHeader, height: u32, txn_matched: &[&Transaction], indexes_of_txn_matched: &[u32]) {
2963                 let header_hash = header.bitcoin_hash();
2964                 log_trace!(self.logger, "Block {} at height {} connected with {} txn matched", header_hash, height, txn_matched.len());
2965                 let _ = self.total_consistency_lock.read().unwrap();
2966                 let mut failed_channels = Vec::new();
2967                 let mut timed_out_htlcs = Vec::new();
2968                 {
2969                         let mut channel_lock = self.channel_state.lock().unwrap();
2970                         let channel_state = &mut *channel_lock;
2971                         let short_to_id = &mut channel_state.short_to_id;
2972                         let pending_msg_events = &mut channel_state.pending_msg_events;
2973                         channel_state.by_id.retain(|_, channel| {
2974                                 let res = channel.block_connected(header, height, txn_matched, indexes_of_txn_matched);
2975                                 if let Ok((chan_res, mut timed_out_pending_htlcs)) = res {
2976                                         for (source, payment_hash) in timed_out_pending_htlcs.drain(..) {
2977                                                 let chan_update = self.get_channel_update(&channel).map(|u| u.encode_with_len()).unwrap(); // Cannot add/recv HTLCs before we have a short_id so unwrap is safe
2978                                                 timed_out_htlcs.push((source, payment_hash,  HTLCFailReason::Reason {
2979                                                         failure_code: 0x1000 | 14, // expiry_too_soon, or at least it is now
2980                                                         data: chan_update,
2981                                                 }));
2982                                         }
2983                                         if let Some(funding_locked) = chan_res {
2984                                                 pending_msg_events.push(events::MessageSendEvent::SendFundingLocked {
2985                                                         node_id: channel.get_their_node_id(),
2986                                                         msg: funding_locked,
2987                                                 });
2988                                                 if let Some(announcement_sigs) = self.get_announcement_sigs(channel) {
2989                                                         log_trace!(self.logger, "Sending funding_locked and announcement_signatures for {}", log_bytes!(channel.channel_id()));
2990                                                         pending_msg_events.push(events::MessageSendEvent::SendAnnouncementSignatures {
2991                                                                 node_id: channel.get_their_node_id(),
2992                                                                 msg: announcement_sigs,
2993                                                         });
2994                                                 } else {
2995                                                         log_trace!(self.logger, "Sending funding_locked WITHOUT announcement_signatures for {}", log_bytes!(channel.channel_id()));
2996                                                 }
2997                                                 short_to_id.insert(channel.get_short_channel_id().unwrap(), channel.channel_id());
2998                                         }
2999                                 } else if let Err(e) = res {
3000                                         pending_msg_events.push(events::MessageSendEvent::HandleError {
3001                                                 node_id: channel.get_their_node_id(),
3002                                                 action: msgs::ErrorAction::SendErrorMessage { msg: e },
3003                                         });
3004                                         return false;
3005                                 }
3006                                 if let Some(funding_txo) = channel.get_funding_txo() {
3007                                         for tx in txn_matched {
3008                                                 for inp in tx.input.iter() {
3009                                                         if inp.previous_output == funding_txo.into_bitcoin_outpoint() {
3010                                                                 log_trace!(self.logger, "Detected channel-closing tx {} spending {}:{}, closing channel {}", tx.txid(), inp.previous_output.txid, inp.previous_output.vout, log_bytes!(channel.channel_id()));
3011                                                                 if let Some(short_id) = channel.get_short_channel_id() {
3012                                                                         short_to_id.remove(&short_id);
3013                                                                 }
3014                                                                 // It looks like our counterparty went on-chain. We go ahead and
3015                                                                 // broadcast our latest local state as well here, just in case its
3016                                                                 // some kind of SPV attack, though we expect these to be dropped.
3017                                                                 failed_channels.push(channel.force_shutdown(true));
3018                                                                 if let Ok(update) = self.get_channel_update(&channel) {
3019                                                                         pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
3020                                                                                 msg: update
3021                                                                         });
3022                                                                 }
3023                                                                 return false;
3024                                                         }
3025                                                 }
3026                                         }
3027                                 }
3028                                 if channel.is_funding_initiated() && channel.channel_monitor().would_broadcast_at_height(height, &self.logger) {
3029                                         if let Some(short_id) = channel.get_short_channel_id() {
3030                                                 short_to_id.remove(&short_id);
3031                                         }
3032                                         // If would_broadcast_at_height() is true, the channel_monitor will broadcast
3033                                         // the latest local tx for us, so we should skip that here (it doesn't really
3034                                         // hurt anything, but does make tests a bit simpler).
3035                                         failed_channels.push(channel.force_shutdown(false));
3036                                         if let Ok(update) = self.get_channel_update(&channel) {
3037                                                 pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
3038                                                         msg: update
3039                                                 });
3040                                         }
3041                                         return false;
3042                                 }
3043                                 true
3044                         });
3045
3046                         channel_state.claimable_htlcs.retain(|&(ref payment_hash, _), htlcs| {
3047                                 htlcs.retain(|htlc| {
3048                                         // If height is approaching the number of blocks we think it takes us to get
3049                                         // our commitment transaction confirmed before the HTLC expires, plus the
3050                                         // number of blocks we generally consider it to take to do a commitment update,
3051                                         // just give up on it and fail the HTLC.
3052                                         if height >= htlc.cltv_expiry - HTLC_FAIL_BACK_BUFFER {
3053                                                 let mut htlc_msat_height_data = byte_utils::be64_to_array(htlc.value).to_vec();
3054                                                 htlc_msat_height_data.extend_from_slice(&byte_utils::be32_to_array(height));
3055                                                 timed_out_htlcs.push((HTLCSource::PreviousHopData(htlc.prev_hop.clone()), payment_hash.clone(), HTLCFailReason::Reason {
3056                                                         failure_code: 0x4000 | 15,
3057                                                         data: htlc_msat_height_data
3058                                                 }));
3059                                                 false
3060                                         } else { true }
3061                                 });
3062                                 !htlcs.is_empty() // Only retain this entry if htlcs has at least one entry.
3063                         });
3064                 }
3065                 for failure in failed_channels.drain(..) {
3066                         self.finish_force_close_channel(failure);
3067                 }
3068
3069                 for (source, payment_hash, reason) in timed_out_htlcs.drain(..) {
3070                         self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), source, &payment_hash, reason);
3071                 }
3072                 self.latest_block_height.store(height as usize, Ordering::Release);
3073                 *self.last_block_hash.try_lock().expect("block_(dis)connected must not be called in parallel") = header_hash;
3074                 loop {
3075                         // Update last_node_announcement_serial to be the max of its current value and the
3076                         // block timestamp. This should keep us close to the current time without relying on
3077                         // having an explicit local time source.
3078                         // Just in case we end up in a race, we loop until we either successfully update
3079                         // last_node_announcement_serial or decide we don't need to.
3080                         let old_serial = self.last_node_announcement_serial.load(Ordering::Acquire);
3081                         if old_serial >= header.time as usize { break; }
3082                         if self.last_node_announcement_serial.compare_exchange(old_serial, header.time as usize, Ordering::AcqRel, Ordering::Relaxed).is_ok() {
3083                                 break;
3084                         }
3085                 }
3086         }
3087
3088         /// We force-close the channel without letting our counterparty participate in the shutdown
3089         fn block_disconnected(&self, header: &BlockHeader, _: u32) {
3090                 let _ = self.total_consistency_lock.read().unwrap();
3091                 let mut failed_channels = Vec::new();
3092                 {
3093                         let mut channel_lock = self.channel_state.lock().unwrap();
3094                         let channel_state = &mut *channel_lock;
3095                         let short_to_id = &mut channel_state.short_to_id;
3096                         let pending_msg_events = &mut channel_state.pending_msg_events;
3097                         channel_state.by_id.retain(|_,  v| {
3098                                 if v.block_disconnected(header) {
3099                                         if let Some(short_id) = v.get_short_channel_id() {
3100                                                 short_to_id.remove(&short_id);
3101                                         }
3102                                         failed_channels.push(v.force_shutdown(true));
3103                                         if let Ok(update) = self.get_channel_update(&v) {
3104                                                 pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
3105                                                         msg: update
3106                                                 });
3107                                         }
3108                                         false
3109                                 } else {
3110                                         true
3111                                 }
3112                         });
3113                 }
3114                 for failure in failed_channels.drain(..) {
3115                         self.finish_force_close_channel(failure);
3116                 }
3117                 self.latest_block_height.fetch_sub(1, Ordering::AcqRel);
3118                 *self.last_block_hash.try_lock().expect("block_(dis)connected must not be called in parallel") = header.bitcoin_hash();
3119         }
3120 }
3121
3122 impl<ChanSigner: ChannelKeys, M: Deref + Sync + Send, T: Deref + Sync + Send, K: Deref + Sync + Send, F: Deref + Sync + Send, L: Deref + Sync + Send>
3123         ChannelMessageHandler for ChannelManager<ChanSigner, M, T, K, F, L>
3124         where M::Target: ManyChannelMonitor<ChanSigner>,
3125         T::Target: BroadcasterInterface,
3126         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
3127         F::Target: FeeEstimator,
3128         L::Target: Logger,
3129 {
3130         fn handle_open_channel(&self, their_node_id: &PublicKey, their_features: InitFeatures, msg: &msgs::OpenChannel) {
3131                 let _ = self.total_consistency_lock.read().unwrap();
3132                 let _ = handle_error!(self, self.internal_open_channel(their_node_id, their_features, msg), *their_node_id);
3133         }
3134
3135         fn handle_accept_channel(&self, their_node_id: &PublicKey, their_features: InitFeatures, msg: &msgs::AcceptChannel) {
3136                 let _ = self.total_consistency_lock.read().unwrap();
3137                 let _ = handle_error!(self, self.internal_accept_channel(their_node_id, their_features, msg), *their_node_id);
3138         }
3139
3140         fn handle_funding_created(&self, their_node_id: &PublicKey, msg: &msgs::FundingCreated) {
3141                 let _ = self.total_consistency_lock.read().unwrap();
3142                 let _ = handle_error!(self, self.internal_funding_created(their_node_id, msg), *their_node_id);
3143         }
3144
3145         fn handle_funding_signed(&self, their_node_id: &PublicKey, msg: &msgs::FundingSigned) {
3146                 let _ = self.total_consistency_lock.read().unwrap();
3147                 let _ = handle_error!(self, self.internal_funding_signed(their_node_id, msg), *their_node_id);
3148         }
3149
3150         fn handle_funding_locked(&self, their_node_id: &PublicKey, msg: &msgs::FundingLocked) {
3151                 let _ = self.total_consistency_lock.read().unwrap();
3152                 let _ = handle_error!(self, self.internal_funding_locked(their_node_id, msg), *their_node_id);
3153         }
3154
3155         fn handle_shutdown(&self, their_node_id: &PublicKey, msg: &msgs::Shutdown) {
3156                 let _ = self.total_consistency_lock.read().unwrap();
3157                 let _ = handle_error!(self, self.internal_shutdown(their_node_id, msg), *their_node_id);
3158         }
3159
3160         fn handle_closing_signed(&self, their_node_id: &PublicKey, msg: &msgs::ClosingSigned) {
3161                 let _ = self.total_consistency_lock.read().unwrap();
3162                 let _ = handle_error!(self, self.internal_closing_signed(their_node_id, msg), *their_node_id);
3163         }
3164
3165         fn handle_update_add_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateAddHTLC) {
3166                 let _ = self.total_consistency_lock.read().unwrap();
3167                 let _ = handle_error!(self, self.internal_update_add_htlc(their_node_id, msg), *their_node_id);
3168         }
3169
3170         fn handle_update_fulfill_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFulfillHTLC) {
3171                 let _ = self.total_consistency_lock.read().unwrap();
3172                 let _ = handle_error!(self, self.internal_update_fulfill_htlc(their_node_id, msg), *their_node_id);
3173         }
3174
3175         fn handle_update_fail_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFailHTLC) {
3176                 let _ = self.total_consistency_lock.read().unwrap();
3177                 let _ = handle_error!(self, self.internal_update_fail_htlc(their_node_id, msg), *their_node_id);
3178         }
3179
3180         fn handle_update_fail_malformed_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFailMalformedHTLC) {
3181                 let _ = self.total_consistency_lock.read().unwrap();
3182                 let _ = handle_error!(self, self.internal_update_fail_malformed_htlc(their_node_id, msg), *their_node_id);
3183         }
3184
3185         fn handle_commitment_signed(&self, their_node_id: &PublicKey, msg: &msgs::CommitmentSigned) {
3186                 let _ = self.total_consistency_lock.read().unwrap();
3187                 let _ = handle_error!(self, self.internal_commitment_signed(their_node_id, msg), *their_node_id);
3188         }
3189
3190         fn handle_revoke_and_ack(&self, their_node_id: &PublicKey, msg: &msgs::RevokeAndACK) {
3191                 let _ = self.total_consistency_lock.read().unwrap();
3192                 let _ = handle_error!(self, self.internal_revoke_and_ack(their_node_id, msg), *their_node_id);
3193         }
3194
3195         fn handle_update_fee(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFee) {
3196                 let _ = self.total_consistency_lock.read().unwrap();
3197                 let _ = handle_error!(self, self.internal_update_fee(their_node_id, msg), *their_node_id);
3198         }
3199
3200         fn handle_announcement_signatures(&self, their_node_id: &PublicKey, msg: &msgs::AnnouncementSignatures) {
3201                 let _ = self.total_consistency_lock.read().unwrap();
3202                 let _ = handle_error!(self, self.internal_announcement_signatures(their_node_id, msg), *their_node_id);
3203         }
3204
3205         fn handle_channel_reestablish(&self, their_node_id: &PublicKey, msg: &msgs::ChannelReestablish) {
3206                 let _ = self.total_consistency_lock.read().unwrap();
3207                 let _ = handle_error!(self, self.internal_channel_reestablish(their_node_id, msg), *their_node_id);
3208         }
3209
3210         fn peer_disconnected(&self, their_node_id: &PublicKey, no_connection_possible: bool) {
3211                 let _ = self.total_consistency_lock.read().unwrap();
3212                 let mut failed_channels = Vec::new();
3213                 let mut failed_payments = Vec::new();
3214                 let mut no_channels_remain = true;
3215                 {
3216                         let mut channel_state_lock = self.channel_state.lock().unwrap();
3217                         let channel_state = &mut *channel_state_lock;
3218                         let short_to_id = &mut channel_state.short_to_id;
3219                         let pending_msg_events = &mut channel_state.pending_msg_events;
3220                         if no_connection_possible {
3221                                 log_debug!(self.logger, "Failing all channels with {} due to no_connection_possible", log_pubkey!(their_node_id));
3222                                 channel_state.by_id.retain(|_, chan| {
3223                                         if chan.get_their_node_id() == *their_node_id {
3224                                                 if let Some(short_id) = chan.get_short_channel_id() {
3225                                                         short_to_id.remove(&short_id);
3226                                                 }
3227                                                 failed_channels.push(chan.force_shutdown(true));
3228                                                 if let Ok(update) = self.get_channel_update(&chan) {
3229                                                         pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
3230                                                                 msg: update
3231                                                         });
3232                                                 }
3233                                                 false
3234                                         } else {
3235                                                 true
3236                                         }
3237                                 });
3238                         } else {
3239                                 log_debug!(self.logger, "Marking channels with {} disconnected and generating channel_updates", log_pubkey!(their_node_id));
3240                                 channel_state.by_id.retain(|_, chan| {
3241                                         if chan.get_their_node_id() == *their_node_id {
3242                                                 let failed_adds = chan.remove_uncommitted_htlcs_and_mark_paused(&self.logger);
3243                                                 chan.to_disabled_marked();
3244                                                 if !failed_adds.is_empty() {
3245                                                         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
3246                                                         failed_payments.push((chan_update, failed_adds));
3247                                                 }
3248                                                 if chan.is_shutdown() {
3249                                                         if let Some(short_id) = chan.get_short_channel_id() {
3250                                                                 short_to_id.remove(&short_id);
3251                                                         }
3252                                                         return false;
3253                                                 } else {
3254                                                         no_channels_remain = false;
3255                                                 }
3256                                         }
3257                                         true
3258                                 })
3259                         }
3260                         pending_msg_events.retain(|msg| {
3261                                 match msg {
3262                                         &events::MessageSendEvent::SendAcceptChannel { ref node_id, .. } => node_id != their_node_id,
3263                                         &events::MessageSendEvent::SendOpenChannel { ref node_id, .. } => node_id != their_node_id,
3264                                         &events::MessageSendEvent::SendFundingCreated { ref node_id, .. } => node_id != their_node_id,
3265                                         &events::MessageSendEvent::SendFundingSigned { ref node_id, .. } => node_id != their_node_id,
3266                                         &events::MessageSendEvent::SendFundingLocked { ref node_id, .. } => node_id != their_node_id,
3267                                         &events::MessageSendEvent::SendAnnouncementSignatures { ref node_id, .. } => node_id != their_node_id,
3268                                         &events::MessageSendEvent::UpdateHTLCs { ref node_id, .. } => node_id != their_node_id,
3269                                         &events::MessageSendEvent::SendRevokeAndACK { ref node_id, .. } => node_id != their_node_id,
3270                                         &events::MessageSendEvent::SendClosingSigned { ref node_id, .. } => node_id != their_node_id,
3271                                         &events::MessageSendEvent::SendShutdown { ref node_id, .. } => node_id != their_node_id,
3272                                         &events::MessageSendEvent::SendChannelReestablish { ref node_id, .. } => node_id != their_node_id,
3273                                         &events::MessageSendEvent::BroadcastChannelAnnouncement { .. } => true,
3274                                         &events::MessageSendEvent::BroadcastNodeAnnouncement { .. } => true,
3275                                         &events::MessageSendEvent::BroadcastChannelUpdate { .. } => true,
3276                                         &events::MessageSendEvent::HandleError { ref node_id, .. } => node_id != their_node_id,
3277                                         &events::MessageSendEvent::PaymentFailureNetworkUpdate { .. } => true,
3278                                 }
3279                         });
3280                 }
3281                 if no_channels_remain {
3282                         self.per_peer_state.write().unwrap().remove(their_node_id);
3283                 }
3284
3285                 for failure in failed_channels.drain(..) {
3286                         self.finish_force_close_channel(failure);
3287                 }
3288                 for (chan_update, mut htlc_sources) in failed_payments {
3289                         for (htlc_source, payment_hash) in htlc_sources.drain(..) {
3290                                 self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), htlc_source, &payment_hash, HTLCFailReason::Reason { failure_code: 0x1000 | 7, data: chan_update.clone() });
3291                         }
3292                 }
3293         }
3294
3295         fn peer_connected(&self, their_node_id: &PublicKey, init_msg: &msgs::Init) {
3296                 log_debug!(self.logger, "Generating channel_reestablish events for {}", log_pubkey!(their_node_id));
3297
3298                 let _ = self.total_consistency_lock.read().unwrap();
3299
3300                 {
3301                         let mut peer_state_lock = self.per_peer_state.write().unwrap();
3302                         match peer_state_lock.entry(their_node_id.clone()) {
3303                                 hash_map::Entry::Vacant(e) => {
3304                                         e.insert(Mutex::new(PeerState {
3305                                                 latest_features: init_msg.features.clone(),
3306                                         }));
3307                                 },
3308                                 hash_map::Entry::Occupied(e) => {
3309                                         e.get().lock().unwrap().latest_features = init_msg.features.clone();
3310                                 },
3311                         }
3312                 }
3313
3314                 let mut channel_state_lock = self.channel_state.lock().unwrap();
3315                 let channel_state = &mut *channel_state_lock;
3316                 let pending_msg_events = &mut channel_state.pending_msg_events;
3317                 channel_state.by_id.retain(|_, chan| {
3318                         if chan.get_their_node_id() == *their_node_id {
3319                                 if !chan.have_received_message() {
3320                                         // If we created this (outbound) channel while we were disconnected from the
3321                                         // peer we probably failed to send the open_channel message, which is now
3322                                         // lost. We can't have had anything pending related to this channel, so we just
3323                                         // drop it.
3324                                         false
3325                                 } else {
3326                                         pending_msg_events.push(events::MessageSendEvent::SendChannelReestablish {
3327                                                 node_id: chan.get_their_node_id(),
3328                                                 msg: chan.get_channel_reestablish(&self.logger),
3329                                         });
3330                                         true
3331                                 }
3332                         } else { true }
3333                 });
3334                 //TODO: Also re-broadcast announcement_signatures
3335         }
3336
3337         fn handle_error(&self, their_node_id: &PublicKey, msg: &msgs::ErrorMessage) {
3338                 let _ = self.total_consistency_lock.read().unwrap();
3339
3340                 if msg.channel_id == [0; 32] {
3341                         for chan in self.list_channels() {
3342                                 if chan.remote_network_id == *their_node_id {
3343                                         self.force_close_channel(&chan.channel_id);
3344                                 }
3345                         }
3346                 } else {
3347                         self.force_close_channel(&msg.channel_id);
3348                 }
3349         }
3350 }
3351
3352 const SERIALIZATION_VERSION: u8 = 1;
3353 const MIN_SERIALIZATION_VERSION: u8 = 1;
3354
3355 impl Writeable for PendingHTLCInfo {
3356         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3357                 match &self.routing {
3358                         &PendingHTLCRouting::Forward { ref onion_packet, ref short_channel_id } => {
3359                                 0u8.write(writer)?;
3360                                 onion_packet.write(writer)?;
3361                                 short_channel_id.write(writer)?;
3362                         },
3363                         &PendingHTLCRouting::Receive { ref payment_data, ref incoming_cltv_expiry } => {
3364                                 1u8.write(writer)?;
3365                                 payment_data.write(writer)?;
3366                                 incoming_cltv_expiry.write(writer)?;
3367                         },
3368                 }
3369                 self.incoming_shared_secret.write(writer)?;
3370                 self.payment_hash.write(writer)?;
3371                 self.amt_to_forward.write(writer)?;
3372                 self.outgoing_cltv_value.write(writer)?;
3373                 Ok(())
3374         }
3375 }
3376
3377 impl Readable for PendingHTLCInfo {
3378         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<PendingHTLCInfo, DecodeError> {
3379                 Ok(PendingHTLCInfo {
3380                         routing: match Readable::read(reader)? {
3381                                 0u8 => PendingHTLCRouting::Forward {
3382                                         onion_packet: Readable::read(reader)?,
3383                                         short_channel_id: Readable::read(reader)?,
3384                                 },
3385                                 1u8 => PendingHTLCRouting::Receive {
3386                                         payment_data: Readable::read(reader)?,
3387                                         incoming_cltv_expiry: Readable::read(reader)?,
3388                                 },
3389                                 _ => return Err(DecodeError::InvalidValue),
3390                         },
3391                         incoming_shared_secret: Readable::read(reader)?,
3392                         payment_hash: Readable::read(reader)?,
3393                         amt_to_forward: Readable::read(reader)?,
3394                         outgoing_cltv_value: Readable::read(reader)?,
3395                 })
3396         }
3397 }
3398
3399 impl Writeable for HTLCFailureMsg {
3400         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3401                 match self {
3402                         &HTLCFailureMsg::Relay(ref fail_msg) => {
3403                                 0u8.write(writer)?;
3404                                 fail_msg.write(writer)?;
3405                         },
3406                         &HTLCFailureMsg::Malformed(ref fail_msg) => {
3407                                 1u8.write(writer)?;
3408                                 fail_msg.write(writer)?;
3409                         }
3410                 }
3411                 Ok(())
3412         }
3413 }
3414
3415 impl Readable for HTLCFailureMsg {
3416         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<HTLCFailureMsg, DecodeError> {
3417                 match <u8 as Readable>::read(reader)? {
3418                         0 => Ok(HTLCFailureMsg::Relay(Readable::read(reader)?)),
3419                         1 => Ok(HTLCFailureMsg::Malformed(Readable::read(reader)?)),
3420                         _ => Err(DecodeError::InvalidValue),
3421                 }
3422         }
3423 }
3424
3425 impl Writeable for PendingHTLCStatus {
3426         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3427                 match self {
3428                         &PendingHTLCStatus::Forward(ref forward_info) => {
3429                                 0u8.write(writer)?;
3430                                 forward_info.write(writer)?;
3431                         },
3432                         &PendingHTLCStatus::Fail(ref fail_msg) => {
3433                                 1u8.write(writer)?;
3434                                 fail_msg.write(writer)?;
3435                         }
3436                 }
3437                 Ok(())
3438         }
3439 }
3440
3441 impl Readable for PendingHTLCStatus {
3442         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<PendingHTLCStatus, DecodeError> {
3443                 match <u8 as Readable>::read(reader)? {
3444                         0 => Ok(PendingHTLCStatus::Forward(Readable::read(reader)?)),
3445                         1 => Ok(PendingHTLCStatus::Fail(Readable::read(reader)?)),
3446                         _ => Err(DecodeError::InvalidValue),
3447                 }
3448         }
3449 }
3450
3451 impl_writeable!(HTLCPreviousHopData, 0, {
3452         short_channel_id,
3453         htlc_id,
3454         incoming_packet_shared_secret
3455 });
3456
3457 impl_writeable!(ClaimableHTLC, 0, {
3458         prev_hop,
3459         value,
3460         payment_data,
3461         cltv_expiry
3462 });
3463
3464 impl Writeable for HTLCSource {
3465         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3466                 match self {
3467                         &HTLCSource::PreviousHopData(ref hop_data) => {
3468                                 0u8.write(writer)?;
3469                                 hop_data.write(writer)?;
3470                         },
3471                         &HTLCSource::OutboundRoute { ref path, ref session_priv, ref first_hop_htlc_msat } => {
3472                                 1u8.write(writer)?;
3473                                 path.write(writer)?;
3474                                 session_priv.write(writer)?;
3475                                 first_hop_htlc_msat.write(writer)?;
3476                         }
3477                 }
3478                 Ok(())
3479         }
3480 }
3481
3482 impl Readable for HTLCSource {
3483         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<HTLCSource, DecodeError> {
3484                 match <u8 as Readable>::read(reader)? {
3485                         0 => Ok(HTLCSource::PreviousHopData(Readable::read(reader)?)),
3486                         1 => Ok(HTLCSource::OutboundRoute {
3487                                 path: Readable::read(reader)?,
3488                                 session_priv: Readable::read(reader)?,
3489                                 first_hop_htlc_msat: Readable::read(reader)?,
3490                         }),
3491                         _ => Err(DecodeError::InvalidValue),
3492                 }
3493         }
3494 }
3495
3496 impl Writeable for HTLCFailReason {
3497         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3498                 match self {
3499                         &HTLCFailReason::LightningError { ref err } => {
3500                                 0u8.write(writer)?;
3501                                 err.write(writer)?;
3502                         },
3503                         &HTLCFailReason::Reason { ref failure_code, ref data } => {
3504                                 1u8.write(writer)?;
3505                                 failure_code.write(writer)?;
3506                                 data.write(writer)?;
3507                         }
3508                 }
3509                 Ok(())
3510         }
3511 }
3512
3513 impl Readable for HTLCFailReason {
3514         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<HTLCFailReason, DecodeError> {
3515                 match <u8 as Readable>::read(reader)? {
3516                         0 => Ok(HTLCFailReason::LightningError { err: Readable::read(reader)? }),
3517                         1 => Ok(HTLCFailReason::Reason {
3518                                 failure_code: Readable::read(reader)?,
3519                                 data: Readable::read(reader)?,
3520                         }),
3521                         _ => Err(DecodeError::InvalidValue),
3522                 }
3523         }
3524 }
3525
3526 impl Writeable for HTLCForwardInfo {
3527         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3528                 match self {
3529                         &HTLCForwardInfo::AddHTLC { ref prev_short_channel_id, ref prev_htlc_id, ref forward_info } => {
3530                                 0u8.write(writer)?;
3531                                 prev_short_channel_id.write(writer)?;
3532                                 prev_htlc_id.write(writer)?;
3533                                 forward_info.write(writer)?;
3534                         },
3535                         &HTLCForwardInfo::FailHTLC { ref htlc_id, ref err_packet } => {
3536                                 1u8.write(writer)?;
3537                                 htlc_id.write(writer)?;
3538                                 err_packet.write(writer)?;
3539                         },
3540                 }
3541                 Ok(())
3542         }
3543 }
3544
3545 impl Readable for HTLCForwardInfo {
3546         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<HTLCForwardInfo, DecodeError> {
3547                 match <u8 as Readable>::read(reader)? {
3548                         0 => Ok(HTLCForwardInfo::AddHTLC {
3549                                 prev_short_channel_id: Readable::read(reader)?,
3550                                 prev_htlc_id: Readable::read(reader)?,
3551                                 forward_info: Readable::read(reader)?,
3552                         }),
3553                         1 => Ok(HTLCForwardInfo::FailHTLC {
3554                                 htlc_id: Readable::read(reader)?,
3555                                 err_packet: Readable::read(reader)?,
3556                         }),
3557                         _ => Err(DecodeError::InvalidValue),
3558                 }
3559         }
3560 }
3561
3562 impl<ChanSigner: ChannelKeys + Writeable, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> Writeable for ChannelManager<ChanSigner, M, T, K, F, L>
3563         where M::Target: ManyChannelMonitor<ChanSigner>,
3564         T::Target: BroadcasterInterface,
3565         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
3566         F::Target: FeeEstimator,
3567         L::Target: Logger,
3568 {
3569         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
3570                 let _ = self.total_consistency_lock.write().unwrap();
3571
3572                 writer.write_all(&[SERIALIZATION_VERSION; 1])?;
3573                 writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
3574
3575                 self.genesis_hash.write(writer)?;
3576                 (self.latest_block_height.load(Ordering::Acquire) as u32).write(writer)?;
3577                 self.last_block_hash.lock().unwrap().write(writer)?;
3578
3579                 let channel_state = self.channel_state.lock().unwrap();
3580                 let mut unfunded_channels = 0;
3581                 for (_, channel) in channel_state.by_id.iter() {
3582                         if !channel.is_funding_initiated() {
3583                                 unfunded_channels += 1;
3584                         }
3585                 }
3586                 ((channel_state.by_id.len() - unfunded_channels) as u64).write(writer)?;
3587                 for (_, channel) in channel_state.by_id.iter() {
3588                         if channel.is_funding_initiated() {
3589                                 channel.write(writer)?;
3590                         }
3591                 }
3592
3593                 (channel_state.forward_htlcs.len() as u64).write(writer)?;
3594                 for (short_channel_id, pending_forwards) in channel_state.forward_htlcs.iter() {
3595                         short_channel_id.write(writer)?;
3596                         (pending_forwards.len() as u64).write(writer)?;
3597                         for forward in pending_forwards {
3598                                 forward.write(writer)?;
3599                         }
3600                 }
3601
3602                 (channel_state.claimable_htlcs.len() as u64).write(writer)?;
3603                 for (payment_hash, previous_hops) in channel_state.claimable_htlcs.iter() {
3604                         payment_hash.write(writer)?;
3605                         (previous_hops.len() as u64).write(writer)?;
3606                         for htlc in previous_hops.iter() {
3607                                 htlc.write(writer)?;
3608                         }
3609                 }
3610
3611                 let per_peer_state = self.per_peer_state.write().unwrap();
3612                 (per_peer_state.len() as u64).write(writer)?;
3613                 for (peer_pubkey, peer_state_mutex) in per_peer_state.iter() {
3614                         peer_pubkey.write(writer)?;
3615                         let peer_state = peer_state_mutex.lock().unwrap();
3616                         peer_state.latest_features.write(writer)?;
3617                 }
3618
3619                 let events = self.pending_events.lock().unwrap();
3620                 (events.len() as u64).write(writer)?;
3621                 for event in events.iter() {
3622                         event.write(writer)?;
3623                 }
3624
3625                 (self.last_node_announcement_serial.load(Ordering::Acquire) as u32).write(writer)?;
3626
3627                 Ok(())
3628         }
3629 }
3630
3631 /// Arguments for the creation of a ChannelManager that are not deserialized.
3632 ///
3633 /// At a high-level, the process for deserializing a ChannelManager and resuming normal operation
3634 /// is:
3635 /// 1) Deserialize all stored ChannelMonitors.
3636 /// 2) Deserialize the ChannelManager by filling in this struct and calling <(Sha256dHash,
3637 ///    ChannelManager)>::read(reader, args).
3638 ///    This may result in closing some Channels if the ChannelMonitor is newer than the stored
3639 ///    ChannelManager state to ensure no loss of funds. Thus, transactions may be broadcasted.
3640 /// 3) Register all relevant ChannelMonitor outpoints with your chain watch mechanism using
3641 ///    ChannelMonitor::get_monitored_outpoints and ChannelMonitor::get_funding_txo().
3642 /// 4) Reconnect blocks on your ChannelMonitors.
3643 /// 5) Move the ChannelMonitors into your local ManyChannelMonitor.
3644 /// 6) Disconnect/connect blocks on the ChannelManager.
3645 /// 7) Register the new ChannelManager with your ChainWatchInterface.
3646 pub struct ChannelManagerReadArgs<'a, ChanSigner: 'a + ChannelKeys, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
3647         where M::Target: ManyChannelMonitor<ChanSigner>,
3648         T::Target: BroadcasterInterface,
3649         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
3650         F::Target: FeeEstimator,
3651         L::Target: Logger,
3652 {
3653
3654         /// The keys provider which will give us relevant keys. Some keys will be loaded during
3655         /// deserialization.
3656         pub keys_manager: K,
3657
3658         /// The fee_estimator for use in the ChannelManager in the future.
3659         ///
3660         /// No calls to the FeeEstimator will be made during deserialization.
3661         pub fee_estimator: F,
3662         /// The ManyChannelMonitor for use in the ChannelManager in the future.
3663         ///
3664         /// No calls to the ManyChannelMonitor will be made during deserialization. It is assumed that
3665         /// you have deserialized ChannelMonitors separately and will add them to your
3666         /// ManyChannelMonitor after deserializing this ChannelManager.
3667         pub monitor: M,
3668
3669         /// The BroadcasterInterface which will be used in the ChannelManager in the future and may be
3670         /// used to broadcast the latest local commitment transactions of channels which must be
3671         /// force-closed during deserialization.
3672         pub tx_broadcaster: T,
3673         /// The Logger for use in the ChannelManager and which may be used to log information during
3674         /// deserialization.
3675         pub logger: L,
3676         /// Default settings used for new channels. Any existing channels will continue to use the
3677         /// runtime settings which were stored when the ChannelManager was serialized.
3678         pub default_config: UserConfig,
3679
3680         /// A map from channel funding outpoints to ChannelMonitors for those channels (ie
3681         /// value.get_funding_txo() should be the key).
3682         ///
3683         /// If a monitor is inconsistent with the channel state during deserialization the channel will
3684         /// be force-closed using the data in the ChannelMonitor and the channel will be dropped. This
3685         /// is true for missing channels as well. If there is a monitor missing for which we find
3686         /// channel data Err(DecodeError::InvalidValue) will be returned.
3687         ///
3688         /// In such cases the latest local transactions will be sent to the tx_broadcaster included in
3689         /// this struct.
3690         pub channel_monitors: &'a mut HashMap<OutPoint, &'a mut ChannelMonitor<ChanSigner>>,
3691 }
3692
3693 // Implement ReadableArgs for an Arc'd ChannelManager to make it a bit easier to work with the
3694 // SipmleArcChannelManager type:
3695 impl<'a, ChanSigner: ChannelKeys + Readable, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
3696         ReadableArgs<ChannelManagerReadArgs<'a, ChanSigner, M, T, K, F, L>> for (BlockHash, Arc<ChannelManager<ChanSigner, M, T, K, F, L>>)
3697         where M::Target: ManyChannelMonitor<ChanSigner>,
3698         T::Target: BroadcasterInterface,
3699         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
3700         F::Target: FeeEstimator,
3701         L::Target: Logger,
3702 {
3703         fn read<R: ::std::io::Read>(reader: &mut R, args: ChannelManagerReadArgs<'a, ChanSigner, M, T, K, F, L>) -> Result<Self, DecodeError> {
3704                 let (blockhash, chan_manager) = <(BlockHash, ChannelManager<ChanSigner, M, T, K, F, L>)>::read(reader, args)?;
3705                 Ok((blockhash, Arc::new(chan_manager)))
3706         }
3707 }
3708
3709 impl<'a, ChanSigner: ChannelKeys + Readable, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
3710         ReadableArgs<ChannelManagerReadArgs<'a, ChanSigner, M, T, K, F, L>> for (BlockHash, ChannelManager<ChanSigner, M, T, K, F, L>)
3711         where M::Target: ManyChannelMonitor<ChanSigner>,
3712         T::Target: BroadcasterInterface,
3713         K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
3714         F::Target: FeeEstimator,
3715         L::Target: Logger,
3716 {
3717         fn read<R: ::std::io::Read>(reader: &mut R, args: ChannelManagerReadArgs<'a, ChanSigner, M, T, K, F, L>) -> Result<Self, DecodeError> {
3718                 let _ver: u8 = Readable::read(reader)?;
3719                 let min_ver: u8 = Readable::read(reader)?;
3720                 if min_ver > SERIALIZATION_VERSION {
3721                         return Err(DecodeError::UnknownVersion);
3722                 }
3723
3724                 let genesis_hash: BlockHash = Readable::read(reader)?;
3725                 let latest_block_height: u32 = Readable::read(reader)?;
3726                 let last_block_hash: BlockHash = Readable::read(reader)?;
3727
3728                 let mut failed_htlcs = Vec::new();
3729
3730                 let channel_count: u64 = Readable::read(reader)?;
3731                 let mut funding_txo_set = HashSet::with_capacity(cmp::min(channel_count as usize, 128));
3732                 let mut by_id = HashMap::with_capacity(cmp::min(channel_count as usize, 128));
3733                 let mut short_to_id = HashMap::with_capacity(cmp::min(channel_count as usize, 128));
3734                 for _ in 0..channel_count {
3735                         let mut channel: Channel<ChanSigner> = Readable::read(reader)?;
3736                         if channel.last_block_connected != Default::default() && channel.last_block_connected != last_block_hash {
3737                                 return Err(DecodeError::InvalidValue);
3738                         }
3739
3740                         let funding_txo = channel.get_funding_txo().ok_or(DecodeError::InvalidValue)?;
3741                         funding_txo_set.insert(funding_txo.clone());
3742                         if let Some(ref mut monitor) = args.channel_monitors.get_mut(&funding_txo) {
3743                                 if channel.get_cur_local_commitment_transaction_number() < monitor.get_cur_local_commitment_number() ||
3744                                                 channel.get_revoked_remote_commitment_transaction_number() < monitor.get_min_seen_secret() ||
3745                                                 channel.get_cur_remote_commitment_transaction_number() < monitor.get_cur_remote_commitment_number() ||
3746                                                 channel.get_latest_monitor_update_id() > monitor.get_latest_update_id() {
3747                                         // If the channel is ahead of the monitor, return InvalidValue:
3748                                         return Err(DecodeError::InvalidValue);
3749                                 } else if channel.get_cur_local_commitment_transaction_number() > monitor.get_cur_local_commitment_number() ||
3750                                                 channel.get_revoked_remote_commitment_transaction_number() > monitor.get_min_seen_secret() ||
3751                                                 channel.get_cur_remote_commitment_transaction_number() > monitor.get_cur_remote_commitment_number() ||
3752                                                 channel.get_latest_monitor_update_id() < monitor.get_latest_update_id() {
3753                                         // But if the channel is behind of the monitor, close the channel:
3754                                         let (_, _, mut new_failed_htlcs) = channel.force_shutdown(true);
3755                                         failed_htlcs.append(&mut new_failed_htlcs);
3756                                         monitor.broadcast_latest_local_commitment_txn(&args.tx_broadcaster, &args.logger);
3757                                 } else {
3758                                         if let Some(short_channel_id) = channel.get_short_channel_id() {
3759                                                 short_to_id.insert(short_channel_id, channel.channel_id());
3760                                         }
3761                                         by_id.insert(channel.channel_id(), channel);
3762                                 }
3763                         } else {
3764                                 return Err(DecodeError::InvalidValue);
3765                         }
3766                 }
3767
3768                 for (ref funding_txo, ref mut monitor) in args.channel_monitors.iter_mut() {
3769                         if !funding_txo_set.contains(funding_txo) {
3770                                 monitor.broadcast_latest_local_commitment_txn(&args.tx_broadcaster, &args.logger);
3771                         }
3772                 }
3773
3774                 const MAX_ALLOC_SIZE: usize = 1024 * 64;
3775                 let forward_htlcs_count: u64 = Readable::read(reader)?;
3776                 let mut forward_htlcs = HashMap::with_capacity(cmp::min(forward_htlcs_count as usize, 128));
3777                 for _ in 0..forward_htlcs_count {
3778                         let short_channel_id = Readable::read(reader)?;
3779                         let pending_forwards_count: u64 = Readable::read(reader)?;
3780                         let mut pending_forwards = Vec::with_capacity(cmp::min(pending_forwards_count as usize, MAX_ALLOC_SIZE/mem::size_of::<HTLCForwardInfo>()));
3781                         for _ in 0..pending_forwards_count {
3782                                 pending_forwards.push(Readable::read(reader)?);
3783                         }
3784                         forward_htlcs.insert(short_channel_id, pending_forwards);
3785                 }
3786
3787                 let claimable_htlcs_count: u64 = Readable::read(reader)?;
3788                 let mut claimable_htlcs = HashMap::with_capacity(cmp::min(claimable_htlcs_count as usize, 128));
3789                 for _ in 0..claimable_htlcs_count {
3790                         let payment_hash = Readable::read(reader)?;
3791                         let previous_hops_len: u64 = Readable::read(reader)?;
3792                         let mut previous_hops = Vec::with_capacity(cmp::min(previous_hops_len as usize, MAX_ALLOC_SIZE/mem::size_of::<ClaimableHTLC>()));
3793                         for _ in 0..previous_hops_len {
3794                                 previous_hops.push(Readable::read(reader)?);
3795                         }
3796                         claimable_htlcs.insert(payment_hash, previous_hops);
3797                 }
3798
3799                 let peer_count: u64 = Readable::read(reader)?;
3800                 let mut per_peer_state = HashMap::with_capacity(cmp::min(peer_count as usize, MAX_ALLOC_SIZE/mem::size_of::<(PublicKey, Mutex<PeerState>)>()));
3801                 for _ in 0..peer_count {
3802                         let peer_pubkey = Readable::read(reader)?;
3803                         let peer_state = PeerState {
3804                                 latest_features: Readable::read(reader)?,
3805                         };
3806                         per_peer_state.insert(peer_pubkey, Mutex::new(peer_state));
3807                 }
3808
3809                 let event_count: u64 = Readable::read(reader)?;
3810                 let mut pending_events_read: Vec<events::Event> = Vec::with_capacity(cmp::min(event_count as usize, MAX_ALLOC_SIZE/mem::size_of::<events::Event>()));
3811                 for _ in 0..event_count {
3812                         match MaybeReadable::read(reader)? {
3813                                 Some(event) => pending_events_read.push(event),
3814                                 None => continue,
3815                         }
3816                 }
3817
3818                 let last_node_announcement_serial: u32 = Readable::read(reader)?;
3819
3820                 let channel_manager = ChannelManager {
3821                         genesis_hash,
3822                         fee_estimator: args.fee_estimator,
3823                         monitor: args.monitor,
3824                         tx_broadcaster: args.tx_broadcaster,
3825
3826                         latest_block_height: AtomicUsize::new(latest_block_height as usize),
3827                         last_block_hash: Mutex::new(last_block_hash),
3828                         secp_ctx: Secp256k1::new(),
3829
3830                         channel_state: Mutex::new(ChannelHolder {
3831                                 by_id,
3832                                 short_to_id,
3833                                 forward_htlcs,
3834                                 claimable_htlcs,
3835                                 pending_msg_events: Vec::new(),
3836                         }),
3837                         our_network_key: args.keys_manager.get_node_secret(),
3838
3839                         last_node_announcement_serial: AtomicUsize::new(last_node_announcement_serial as usize),
3840
3841                         per_peer_state: RwLock::new(per_peer_state),
3842
3843                         pending_events: Mutex::new(pending_events_read),
3844                         total_consistency_lock: RwLock::new(()),
3845                         keys_manager: args.keys_manager,
3846                         logger: args.logger,
3847                         default_configuration: args.default_config,
3848                 };
3849
3850                 for htlc_source in failed_htlcs.drain(..) {
3851                         channel_manager.fail_htlc_backwards_internal(channel_manager.channel_state.lock().unwrap(), htlc_source.0, &htlc_source.1, HTLCFailReason::Reason { failure_code: 0x4000 | 8, data: Vec::new() });
3852                 }
3853
3854                 //TODO: Broadcast channel update for closed channels, but only after we've made a
3855                 //connection or two.
3856
3857                 Ok((last_block_hash.clone(), channel_manager))
3858         }
3859 }