1 // This file is Copyright its original authors, visible in version control
4 // This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
5 // or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
6 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
7 // You may not use this file except in accordance with one or both of these
10 //! The logic to monitor for on-chain transactions and create the relevant claim responses lives
13 //! ChannelMonitor objects are generated by ChannelManager in response to relevant
14 //! messages/actions, and MUST be persisted to disk (and, preferably, remotely) before progress can
15 //! be made in responding to certain messages, see [`chain::Watch`] for more.
17 //! Note that ChannelMonitors are an important part of the lightning trust model and a copy of the
18 //! latest ChannelMonitor must always be actively monitoring for chain updates (and no out-of-date
19 //! ChannelMonitors should do so). Thus, if you're building rust-lightning into an HSM or other
20 //! security-domain-separated system design, you should consider having multiple paths for
21 //! ChannelMonitors to get out of the HSM and onto monitoring devices.
23 use bitcoin::blockdata::block::{Block, BlockHeader};
24 use bitcoin::blockdata::transaction::{TxOut,Transaction};
25 use bitcoin::blockdata::script::{Script, Builder};
26 use bitcoin::blockdata::opcodes;
28 use bitcoin::hashes::Hash;
29 use bitcoin::hashes::sha256::Hash as Sha256;
30 use bitcoin::hash_types::{Txid, BlockHash, WPubkeyHash};
32 use bitcoin::secp256k1::{Secp256k1,Signature};
33 use bitcoin::secp256k1::key::{SecretKey,PublicKey};
34 use bitcoin::secp256k1;
36 use ln::{PaymentHash, PaymentPreimage};
37 use ln::msgs::DecodeError;
39 use ln::chan_utils::{CounterpartyCommitmentSecrets, HTLCOutputInCommitment, HTLCType, ChannelTransactionParameters, HolderCommitmentTransaction};
40 use ln::channelmanager::{BestBlock, HTLCSource};
42 use chain::WatchedOutput;
43 use chain::chaininterface::{BroadcasterInterface, FeeEstimator};
44 use chain::transaction::{OutPoint, TransactionData};
45 use chain::keysinterface::{SpendableOutputDescriptor, StaticPaymentOutputDescriptor, DelayedPaymentOutputDescriptor, Sign, KeysInterface};
46 use chain::onchaintx::OnchainTxHandler;
47 use chain::package::{CounterpartyOfferedHTLCOutput, CounterpartyReceivedHTLCOutput, HolderFundingOutput, HolderHTLCOutput, PackageSolvingData, PackageTemplate, RevokedOutput, RevokedHTLCOutput};
49 use util::logger::Logger;
50 use util::ser::{Readable, ReadableArgs, MaybeReadable, Writer, Writeable, U48, OptionDeserWrapper};
52 use util::events::Event;
55 use std::collections::{HashMap, HashSet};
61 /// An update generated by the underlying Channel itself which contains some new information the
62 /// ChannelMonitor should be made aware of.
63 #[cfg_attr(any(test, feature = "fuzztarget", feature = "_test_utils"), derive(PartialEq))]
66 pub struct ChannelMonitorUpdate {
67 pub(crate) updates: Vec<ChannelMonitorUpdateStep>,
68 /// The sequence number of this update. Updates *must* be replayed in-order according to this
69 /// sequence number (and updates may panic if they are not). The update_id values are strictly
70 /// increasing and increase by one for each new update, with one exception specified below.
72 /// This sequence number is also used to track up to which points updates which returned
73 /// ChannelMonitorUpdateErr::TemporaryFailure have been applied to all copies of a given
74 /// ChannelMonitor when ChannelManager::channel_monitor_updated is called.
76 /// The only instance where update_id values are not strictly increasing is the case where we
77 /// allow post-force-close updates with a special update ID of [`CLOSED_CHANNEL_UPDATE_ID`]. See
78 /// its docs for more details.
83 /// (1) a channel has been force closed and
84 /// (2) we receive a preimage from a forward link that allows us to spend an HTLC output on
85 /// this channel's (the backward link's) broadcasted commitment transaction
86 /// then we allow the `ChannelManager` to send a `ChannelMonitorUpdate` with this update ID,
87 /// with the update providing said payment preimage. No other update types are allowed after
89 pub const CLOSED_CHANNEL_UPDATE_ID: u64 = core::u64::MAX;
91 impl Writeable for ChannelMonitorUpdate {
92 fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
93 write_ver_prefix!(w, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
94 self.update_id.write(w)?;
95 (self.updates.len() as u64).write(w)?;
96 for update_step in self.updates.iter() {
97 update_step.write(w)?;
99 write_tlv_fields!(w, {}, {});
103 impl Readable for ChannelMonitorUpdate {
104 fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
105 let _ver = read_ver_prefix!(r, SERIALIZATION_VERSION);
106 let update_id: u64 = Readable::read(r)?;
107 let len: u64 = Readable::read(r)?;
108 let mut updates = Vec::with_capacity(cmp::min(len as usize, MAX_ALLOC_SIZE / ::core::mem::size_of::<ChannelMonitorUpdateStep>()));
110 updates.push(Readable::read(r)?);
112 read_tlv_fields!(r, {}, {});
113 Ok(Self { update_id, updates })
117 /// An error enum representing a failure to persist a channel monitor update.
118 #[derive(Clone, Debug)]
119 pub enum ChannelMonitorUpdateErr {
120 /// Used to indicate a temporary failure (eg connection to a watchtower or remote backup of
121 /// our state failed, but is expected to succeed at some point in the future).
123 /// Such a failure will "freeze" a channel, preventing us from revoking old states or
124 /// submitting new commitment transactions to the counterparty. Once the update(s) which failed
125 /// have been successfully applied, ChannelManager::channel_monitor_updated can be used to
126 /// restore the channel to an operational state.
128 /// Note that a given ChannelManager will *never* re-generate a given ChannelMonitorUpdate. If
129 /// you return a TemporaryFailure you must ensure that it is written to disk safely before
130 /// writing out the latest ChannelManager state.
132 /// Even when a channel has been "frozen" updates to the ChannelMonitor can continue to occur
133 /// (eg if an inbound HTLC which we forwarded was claimed upstream resulting in us attempting
134 /// to claim it on this channel) and those updates must be applied wherever they can be. At
135 /// least one such updated ChannelMonitor must be persisted otherwise PermanentFailure should
136 /// be returned to get things on-chain ASAP using only the in-memory copy. Obviously updates to
137 /// the channel which would invalidate previous ChannelMonitors are not made when a channel has
140 /// Note that even if updates made after TemporaryFailure succeed you must still call
141 /// channel_monitor_updated to ensure you have the latest monitor and re-enable normal channel
144 /// Note that the update being processed here will not be replayed for you when you call
145 /// ChannelManager::channel_monitor_updated, so you must store the update itself along
146 /// with the persisted ChannelMonitor on your own local disk prior to returning a
147 /// TemporaryFailure. You may, of course, employ a journaling approach, storing only the
148 /// ChannelMonitorUpdate on disk without updating the monitor itself, replaying the journal at
151 /// For deployments where a copy of ChannelMonitors and other local state are backed up in a
152 /// remote location (with local copies persisted immediately), it is anticipated that all
153 /// updates will return TemporaryFailure until the remote copies could be updated.
155 /// Used to indicate no further channel monitor updates will be allowed (eg we've moved on to a
156 /// different watchtower and cannot update with all watchtowers that were previously informed
157 /// of this channel).
159 /// At reception of this error, ChannelManager will force-close the channel and return at
160 /// least a final ChannelMonitorUpdate::ChannelForceClosed which must be delivered to at
161 /// least one ChannelMonitor copy. Revocation secret MUST NOT be released and offchain channel
162 /// update must be rejected.
164 /// This failure may also signal a failure to update the local persisted copy of one of
165 /// the channel monitor instance.
167 /// Note that even when you fail a holder commitment transaction update, you must store the
168 /// update to ensure you can claim from it in case of a duplicate copy of this ChannelMonitor
169 /// broadcasts it (e.g distributed channel-monitor deployment)
171 /// In case of distributed watchtowers deployment, the new version must be written to disk, as
172 /// state may have been stored but rejected due to a block forcing a commitment broadcast. This
173 /// storage is used to claim outputs of rejected state confirmed onchain by another watchtower,
174 /// lagging behind on block processing.
178 /// General Err type for ChannelMonitor actions. Generally, this implies that the data provided is
179 /// inconsistent with the ChannelMonitor being called. eg for ChannelMonitor::update_monitor this
180 /// means you tried to update a monitor for a different channel or the ChannelMonitorUpdate was
182 /// Contains a developer-readable error message.
183 #[derive(Clone, Debug)]
184 pub struct MonitorUpdateError(pub &'static str);
186 /// An event to be processed by the ChannelManager.
187 #[derive(Clone, PartialEq)]
188 pub enum MonitorEvent {
189 /// A monitor event containing an HTLCUpdate.
190 HTLCEvent(HTLCUpdate),
192 /// A monitor event that the Channel's commitment transaction was broadcasted.
193 CommitmentTxBroadcasted(OutPoint),
196 /// Simple structure sent back by `chain::Watch` when an HTLC from a forward channel is detected on
197 /// chain. Used to update the corresponding HTLC in the backward channel. Failing to pass the
198 /// preimage claim backward will lead to loss of funds.
199 #[derive(Clone, PartialEq)]
200 pub struct HTLCUpdate {
201 pub(crate) payment_hash: PaymentHash,
202 pub(crate) payment_preimage: Option<PaymentPreimage>,
203 pub(crate) source: HTLCSource
205 impl_writeable_tlv_based!(HTLCUpdate, {
209 (4, payment_preimage)
212 /// If an HTLC expires within this many blocks, don't try to claim it in a shared transaction,
213 /// instead claiming it in its own individual transaction.
214 pub(crate) const CLTV_SHARED_CLAIM_BUFFER: u32 = 12;
215 /// If an HTLC expires within this many blocks, force-close the channel to broadcast the
216 /// HTLC-Success transaction.
217 /// In other words, this is an upper bound on how many blocks we think it can take us to get a
218 /// transaction confirmed (and we use it in a few more, equivalent, places).
219 pub(crate) const CLTV_CLAIM_BUFFER: u32 = 18;
220 /// Number of blocks by which point we expect our counterparty to have seen new blocks on the
221 /// network and done a full update_fail_htlc/commitment_signed dance (+ we've updated all our
222 /// copies of ChannelMonitors, including watchtowers). We could enforce the contract by failing
223 /// at CLTV expiration height but giving a grace period to our peer may be profitable for us if he
224 /// can provide an over-late preimage. Nevertheless, grace period has to be accounted in our
225 /// CLTV_EXPIRY_DELTA to be secure. Following this policy we may decrease the rate of channel failures
226 /// due to expiration but increase the cost of funds being locked longuer in case of failure.
227 /// This delay also cover a low-power peer being slow to process blocks and so being behind us on
228 /// accurate block height.
229 /// In case of onchain failure to be pass backward we may see the last block of ANTI_REORG_DELAY
230 /// with at worst this delay, so we are not only using this value as a mercy for them but also
231 /// us as a safeguard to delay with enough time.
232 pub(crate) const LATENCY_GRACE_PERIOD_BLOCKS: u32 = 3;
233 /// Number of blocks we wait on seeing a HTLC output being solved before we fail corresponding inbound
234 /// HTLCs. This prevents us from failing backwards and then getting a reorg resulting in us losing money.
235 // We also use this delay to be sure we can remove our in-flight claim txn from bump candidates buffer.
236 // It may cause spurious generation of bumped claim txn but that's alright given the outpoint is already
237 // solved by a previous claim tx. What we want to avoid is reorg evicting our claim tx and us not
238 // keep bumping another claim tx to solve the outpoint.
239 pub const ANTI_REORG_DELAY: u32 = 6;
240 /// Number of blocks before confirmation at which we fail back an un-relayed HTLC or at which we
241 /// refuse to accept a new HTLC.
243 /// This is used for a few separate purposes:
244 /// 1) if we've received an MPP HTLC to us and it expires within this many blocks and we are
245 /// waiting on additional parts (or waiting on the preimage for any HTLC from the user), we will
247 /// 2) if we receive an HTLC within this many blocks of its expiry (plus one to avoid a race
248 /// condition with the above), we will fail this HTLC without telling the user we received it,
249 /// 3) if we are waiting on a connection or a channel state update to send an HTLC to a peer, and
250 /// that HTLC expires within this many blocks, we will simply fail the HTLC instead.
252 /// (1) is all about protecting us - we need enough time to update the channel state before we hit
253 /// CLTV_CLAIM_BUFFER, at which point we'd go on chain to claim the HTLC with the preimage.
255 /// (2) is the same, but with an additional buffer to avoid accepting an HTLC which is immediately
256 /// in a race condition between the user connecting a block (which would fail it) and the user
257 /// providing us the preimage (which would claim it).
259 /// (3) is about our counterparty - we don't want to relay an HTLC to a counterparty when they may
260 /// end up force-closing the channel on us to claim it.
261 pub(crate) const HTLC_FAIL_BACK_BUFFER: u32 = CLTV_CLAIM_BUFFER + LATENCY_GRACE_PERIOD_BLOCKS;
263 // TODO(devrandom) replace this with HolderCommitmentTransaction
264 #[derive(Clone, PartialEq)]
265 struct HolderSignedTx {
266 /// txid of the transaction in tx, just used to make comparison faster
268 revocation_key: PublicKey,
269 a_htlc_key: PublicKey,
270 b_htlc_key: PublicKey,
271 delayed_payment_key: PublicKey,
272 per_commitment_point: PublicKey,
274 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
276 impl_writeable_tlv_based!(HolderSignedTx, {
281 (8, delayed_payment_key),
282 (10, per_commitment_point),
283 (12, feerate_per_kw),
288 /// We use this to track counterparty commitment transactions and htlcs outputs and
289 /// use it to generate any justice or 2nd-stage preimage/timeout transactions.
291 struct CounterpartyCommitmentTransaction {
292 counterparty_delayed_payment_base_key: PublicKey,
293 counterparty_htlc_base_key: PublicKey,
294 on_counterparty_tx_csv: u16,
295 per_htlc: HashMap<Txid, Vec<HTLCOutputInCommitment>>
298 impl Writeable for CounterpartyCommitmentTransaction {
299 fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
300 w.write_all(&byte_utils::be64_to_array(self.per_htlc.len() as u64))?;
301 for (ref txid, ref htlcs) in self.per_htlc.iter() {
302 w.write_all(&txid[..])?;
303 w.write_all(&byte_utils::be64_to_array(htlcs.len() as u64))?;
304 for &ref htlc in htlcs.iter() {
308 write_tlv_fields!(w, {
309 (0, self.counterparty_delayed_payment_base_key),
310 (2, self.counterparty_htlc_base_key),
311 (4, self.on_counterparty_tx_csv),
316 impl Readable for CounterpartyCommitmentTransaction {
317 fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
318 let counterparty_commitment_transaction = {
319 let per_htlc_len: u64 = Readable::read(r)?;
320 let mut per_htlc = HashMap::with_capacity(cmp::min(per_htlc_len as usize, MAX_ALLOC_SIZE / 64));
321 for _ in 0..per_htlc_len {
322 let txid: Txid = Readable::read(r)?;
323 let htlcs_count: u64 = Readable::read(r)?;
324 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
325 for _ in 0..htlcs_count {
326 let htlc = Readable::read(r)?;
329 if let Some(_) = per_htlc.insert(txid, htlcs) {
330 return Err(DecodeError::InvalidValue);
333 let mut counterparty_delayed_payment_base_key = OptionDeserWrapper(None);
334 let mut counterparty_htlc_base_key = OptionDeserWrapper(None);
335 let mut on_counterparty_tx_csv: u16 = 0;
336 read_tlv_fields!(r, {
337 (0, counterparty_delayed_payment_base_key),
338 (2, counterparty_htlc_base_key),
339 (4, on_counterparty_tx_csv),
341 CounterpartyCommitmentTransaction {
342 counterparty_delayed_payment_base_key: counterparty_delayed_payment_base_key.0.unwrap(),
343 counterparty_htlc_base_key: counterparty_htlc_base_key.0.unwrap(),
344 on_counterparty_tx_csv,
348 Ok(counterparty_commitment_transaction)
352 /// An entry for an [`OnchainEvent`], stating the block height when the event was observed and the
353 /// transaction causing it.
355 /// Used to determine when the on-chain event can be considered safe from a chain reorganization.
357 struct OnchainEventEntry {
363 impl OnchainEventEntry {
364 fn confirmation_threshold(&self) -> u32 {
365 let mut conf_threshold = self.height + ANTI_REORG_DELAY - 1;
366 if let OnchainEvent::MaturingOutput {
367 descriptor: SpendableOutputDescriptor::DelayedPaymentOutput(ref descriptor)
369 // A CSV'd transaction is confirmable in block (input height) + CSV delay, which means
370 // it's broadcastable when we see the previous block.
371 conf_threshold = cmp::max(conf_threshold, self.height + descriptor.to_self_delay as u32 - 1);
376 fn has_reached_confirmation_threshold(&self, height: u32) -> bool {
377 height >= self.confirmation_threshold()
381 /// Upon discovering of some classes of onchain tx by ChannelMonitor, we may have to take actions on it
382 /// once they mature to enough confirmations (ANTI_REORG_DELAY)
385 /// HTLC output getting solved by a timeout, at maturation we pass upstream payment source information to solve
386 /// inbound HTLC in backward channel. Note, in case of preimage, we pass info to upstream without delay as we can
387 /// only win from it, so it's never an OnchainEvent
390 payment_hash: PaymentHash,
393 descriptor: SpendableOutputDescriptor,
397 impl_writeable_tlv_based!(OnchainEventEntry, {
403 impl_writeable_tlv_based_enum!(OnchainEvent,
408 (1, MaturingOutput) => {
413 #[cfg_attr(any(test, feature = "fuzztarget", feature = "_test_utils"), derive(PartialEq))]
415 pub(crate) enum ChannelMonitorUpdateStep {
416 LatestHolderCommitmentTXInfo {
417 commitment_tx: HolderCommitmentTransaction,
418 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
420 LatestCounterpartyCommitmentTXInfo {
421 commitment_txid: Txid,
422 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
423 commitment_number: u64,
424 their_revocation_point: PublicKey,
427 payment_preimage: PaymentPreimage,
433 /// Used to indicate that the no future updates will occur, and likely that the latest holder
434 /// commitment transaction(s) should be broadcast, as the channel has been force-closed.
436 /// If set to false, we shouldn't broadcast the latest holder commitment transaction as we
437 /// think we've fallen behind!
438 should_broadcast: bool,
442 impl_writeable_tlv_based_enum!(ChannelMonitorUpdateStep,
443 (0, LatestHolderCommitmentTXInfo) => {
448 (1, LatestCounterpartyCommitmentTXInfo) => {
449 (0, commitment_txid),
450 (2, commitment_number),
451 (4, their_revocation_point),
455 (2, PaymentPreimage) => {
456 (0, payment_preimage),
458 (3, CommitmentSecret) => {
462 (4, ChannelForceClosed) => {
463 (0, should_broadcast),
467 /// A ChannelMonitor handles chain events (blocks connected and disconnected) and generates
468 /// on-chain transactions to ensure no loss of funds occurs.
470 /// You MUST ensure that no ChannelMonitors for a given channel anywhere contain out-of-date
471 /// information and are actively monitoring the chain.
473 /// Pending Events or updated HTLCs which have not yet been read out by
474 /// get_and_clear_pending_monitor_events or get_and_clear_pending_events are serialized to disk and
475 /// reloaded at deserialize-time. Thus, you must ensure that, when handling events, all events
476 /// gotten are fully handled before re-serializing the new state.
478 /// Note that the deserializer is only implemented for (BlockHash, ChannelMonitor), which
479 /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
480 /// the "reorg path" (ie disconnecting blocks until you find a common ancestor from both the
481 /// returned block hash and the the current chain and then reconnecting blocks to get to the
482 /// best chain) upon deserializing the object!
483 pub struct ChannelMonitor<Signer: Sign> {
485 pub(crate) inner: Mutex<ChannelMonitorImpl<Signer>>,
487 inner: Mutex<ChannelMonitorImpl<Signer>>,
490 pub(crate) struct ChannelMonitorImpl<Signer: Sign> {
491 latest_update_id: u64,
492 commitment_transaction_number_obscure_factor: u64,
494 destination_script: Script,
495 broadcasted_holder_revokable_script: Option<(Script, PublicKey, PublicKey)>,
496 counterparty_payment_script: Script,
497 shutdown_script: Script,
499 channel_keys_id: [u8; 32],
500 holder_revocation_basepoint: PublicKey,
501 funding_info: (OutPoint, Script),
502 current_counterparty_commitment_txid: Option<Txid>,
503 prev_counterparty_commitment_txid: Option<Txid>,
505 counterparty_tx_cache: CounterpartyCommitmentTransaction,
506 funding_redeemscript: Script,
507 channel_value_satoshis: u64,
508 // first is the idx of the first of the two revocation points
509 their_cur_revocation_points: Option<(u64, PublicKey, Option<PublicKey>)>,
511 on_holder_tx_csv: u16,
513 commitment_secrets: CounterpartyCommitmentSecrets,
514 counterparty_claimable_outpoints: HashMap<Txid, Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>>,
515 /// We cannot identify HTLC-Success or HTLC-Timeout transactions by themselves on the chain.
516 /// Nor can we figure out their commitment numbers without the commitment transaction they are
517 /// spending. Thus, in order to claim them via revocation key, we track all the counterparty
518 /// commitment transactions which we find on-chain, mapping them to the commitment number which
519 /// can be used to derive the revocation key and claim the transactions.
520 counterparty_commitment_txn_on_chain: HashMap<Txid, u64>,
521 /// Cache used to make pruning of payment_preimages faster.
522 /// Maps payment_hash values to commitment numbers for counterparty transactions for non-revoked
523 /// counterparty transactions (ie should remain pretty small).
524 /// Serialized to disk but should generally not be sent to Watchtowers.
525 counterparty_hash_commitment_number: HashMap<PaymentHash, u64>,
527 // We store two holder commitment transactions to avoid any race conditions where we may update
528 // some monitors (potentially on watchtowers) but then fail to update others, resulting in the
529 // various monitors for one channel being out of sync, and us broadcasting a holder
530 // transaction for which we have deleted claim information on some watchtowers.
531 prev_holder_signed_commitment_tx: Option<HolderSignedTx>,
532 current_holder_commitment_tx: HolderSignedTx,
534 // Used just for ChannelManager to make sure it has the latest channel data during
536 current_counterparty_commitment_number: u64,
537 // Used just for ChannelManager to make sure it has the latest channel data during
539 current_holder_commitment_number: u64,
541 payment_preimages: HashMap<PaymentHash, PaymentPreimage>,
543 pending_monitor_events: Vec<MonitorEvent>,
544 pending_events: Vec<Event>,
546 // Used to track on-chain events (i.e., transactions part of channels confirmed on chain) on
547 // which to take actions once they reach enough confirmations. Each entry includes the
548 // transaction's id and the height when the transaction was confirmed on chain.
549 onchain_events_awaiting_threshold_conf: Vec<OnchainEventEntry>,
551 // If we get serialized out and re-read, we need to make sure that the chain monitoring
552 // interface knows about the TXOs that we want to be notified of spends of. We could probably
553 // be smart and derive them from the above storage fields, but its much simpler and more
554 // Obviously Correct (tm) if we just keep track of them explicitly.
555 outputs_to_watch: HashMap<Txid, Vec<(u32, Script)>>,
558 pub onchain_tx_handler: OnchainTxHandler<Signer>,
560 onchain_tx_handler: OnchainTxHandler<Signer>,
562 // This is set when the Channel[Manager] generated a ChannelMonitorUpdate which indicated the
563 // channel has been force-closed. After this is set, no further holder commitment transaction
564 // updates may occur, and we panic!() if one is provided.
565 lockdown_from_offchain: bool,
567 // Set once we've signed a holder commitment transaction and handed it over to our
568 // OnchainTxHandler. After this is set, no future updates to our holder commitment transactions
569 // may occur, and we fail any such monitor updates.
571 // In case of update rejection due to a locally already signed commitment transaction, we
572 // nevertheless store update content to track in case of concurrent broadcast by another
573 // remote monitor out-of-order with regards to the block view.
574 holder_tx_signed: bool,
576 // We simply modify best_block in Channel's block_connected so that serialization is
577 // consistent but hopefully the users' copy handles block_connected in a consistent way.
578 // (we do *not*, however, update them in update_monitor to ensure any local user copies keep
579 // their best_block from its state and not based on updated copies that didn't run through
580 // the full block_connected).
581 best_block: BestBlock,
583 secp_ctx: Secp256k1<secp256k1::All>, //TODO: dedup this a bit...
586 /// Transaction outputs to watch for on-chain spends.
587 pub type TransactionOutputs = (Txid, Vec<(u32, TxOut)>);
589 #[cfg(any(test, feature = "fuzztarget", feature = "_test_utils"))]
590 /// Used only in testing and fuzztarget to check serialization roundtrips don't change the
591 /// underlying object
592 impl<Signer: Sign> PartialEq for ChannelMonitor<Signer> {
593 fn eq(&self, other: &Self) -> bool {
594 let inner = self.inner.lock().unwrap();
595 let other = other.inner.lock().unwrap();
600 #[cfg(any(test, feature = "fuzztarget", feature = "_test_utils"))]
601 /// Used only in testing and fuzztarget to check serialization roundtrips don't change the
602 /// underlying object
603 impl<Signer: Sign> PartialEq for ChannelMonitorImpl<Signer> {
604 fn eq(&self, other: &Self) -> bool {
605 if self.latest_update_id != other.latest_update_id ||
606 self.commitment_transaction_number_obscure_factor != other.commitment_transaction_number_obscure_factor ||
607 self.destination_script != other.destination_script ||
608 self.broadcasted_holder_revokable_script != other.broadcasted_holder_revokable_script ||
609 self.counterparty_payment_script != other.counterparty_payment_script ||
610 self.channel_keys_id != other.channel_keys_id ||
611 self.holder_revocation_basepoint != other.holder_revocation_basepoint ||
612 self.funding_info != other.funding_info ||
613 self.current_counterparty_commitment_txid != other.current_counterparty_commitment_txid ||
614 self.prev_counterparty_commitment_txid != other.prev_counterparty_commitment_txid ||
615 self.counterparty_tx_cache != other.counterparty_tx_cache ||
616 self.funding_redeemscript != other.funding_redeemscript ||
617 self.channel_value_satoshis != other.channel_value_satoshis ||
618 self.their_cur_revocation_points != other.their_cur_revocation_points ||
619 self.on_holder_tx_csv != other.on_holder_tx_csv ||
620 self.commitment_secrets != other.commitment_secrets ||
621 self.counterparty_claimable_outpoints != other.counterparty_claimable_outpoints ||
622 self.counterparty_commitment_txn_on_chain != other.counterparty_commitment_txn_on_chain ||
623 self.counterparty_hash_commitment_number != other.counterparty_hash_commitment_number ||
624 self.prev_holder_signed_commitment_tx != other.prev_holder_signed_commitment_tx ||
625 self.current_counterparty_commitment_number != other.current_counterparty_commitment_number ||
626 self.current_holder_commitment_number != other.current_holder_commitment_number ||
627 self.current_holder_commitment_tx != other.current_holder_commitment_tx ||
628 self.payment_preimages != other.payment_preimages ||
629 self.pending_monitor_events != other.pending_monitor_events ||
630 self.pending_events.len() != other.pending_events.len() || // We trust events to round-trip properly
631 self.onchain_events_awaiting_threshold_conf != other.onchain_events_awaiting_threshold_conf ||
632 self.outputs_to_watch != other.outputs_to_watch ||
633 self.lockdown_from_offchain != other.lockdown_from_offchain ||
634 self.holder_tx_signed != other.holder_tx_signed
643 impl<Signer: Sign> Writeable for ChannelMonitor<Signer> {
644 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), Error> {
645 self.inner.lock().unwrap().write(writer)
649 // These are also used for ChannelMonitorUpdate, above.
650 const SERIALIZATION_VERSION: u8 = 1;
651 const MIN_SERIALIZATION_VERSION: u8 = 1;
653 impl<Signer: Sign> Writeable for ChannelMonitorImpl<Signer> {
654 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), Error> {
655 write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
657 self.latest_update_id.write(writer)?;
659 // Set in initial Channel-object creation, so should always be set by now:
660 U48(self.commitment_transaction_number_obscure_factor).write(writer)?;
662 self.destination_script.write(writer)?;
663 if let Some(ref broadcasted_holder_revokable_script) = self.broadcasted_holder_revokable_script {
664 writer.write_all(&[0; 1])?;
665 broadcasted_holder_revokable_script.0.write(writer)?;
666 broadcasted_holder_revokable_script.1.write(writer)?;
667 broadcasted_holder_revokable_script.2.write(writer)?;
669 writer.write_all(&[1; 1])?;
672 self.counterparty_payment_script.write(writer)?;
673 self.shutdown_script.write(writer)?;
675 self.channel_keys_id.write(writer)?;
676 self.holder_revocation_basepoint.write(writer)?;
677 writer.write_all(&self.funding_info.0.txid[..])?;
678 writer.write_all(&byte_utils::be16_to_array(self.funding_info.0.index))?;
679 self.funding_info.1.write(writer)?;
680 self.current_counterparty_commitment_txid.write(writer)?;
681 self.prev_counterparty_commitment_txid.write(writer)?;
683 self.counterparty_tx_cache.write(writer)?;
684 self.funding_redeemscript.write(writer)?;
685 self.channel_value_satoshis.write(writer)?;
687 match self.their_cur_revocation_points {
688 Some((idx, pubkey, second_option)) => {
689 writer.write_all(&byte_utils::be48_to_array(idx))?;
690 writer.write_all(&pubkey.serialize())?;
691 match second_option {
692 Some(second_pubkey) => {
693 writer.write_all(&second_pubkey.serialize())?;
696 writer.write_all(&[0; 33])?;
701 writer.write_all(&byte_utils::be48_to_array(0))?;
705 writer.write_all(&byte_utils::be16_to_array(self.on_holder_tx_csv))?;
707 self.commitment_secrets.write(writer)?;
709 macro_rules! serialize_htlc_in_commitment {
710 ($htlc_output: expr) => {
711 writer.write_all(&[$htlc_output.offered as u8; 1])?;
712 writer.write_all(&byte_utils::be64_to_array($htlc_output.amount_msat))?;
713 writer.write_all(&byte_utils::be32_to_array($htlc_output.cltv_expiry))?;
714 writer.write_all(&$htlc_output.payment_hash.0[..])?;
715 $htlc_output.transaction_output_index.write(writer)?;
719 writer.write_all(&byte_utils::be64_to_array(self.counterparty_claimable_outpoints.len() as u64))?;
720 for (ref txid, ref htlc_infos) in self.counterparty_claimable_outpoints.iter() {
721 writer.write_all(&txid[..])?;
722 writer.write_all(&byte_utils::be64_to_array(htlc_infos.len() as u64))?;
723 for &(ref htlc_output, ref htlc_source) in htlc_infos.iter() {
724 serialize_htlc_in_commitment!(htlc_output);
725 htlc_source.as_ref().map(|b| b.as_ref()).write(writer)?;
729 writer.write_all(&byte_utils::be64_to_array(self.counterparty_commitment_txn_on_chain.len() as u64))?;
730 for (ref txid, commitment_number) in self.counterparty_commitment_txn_on_chain.iter() {
731 writer.write_all(&txid[..])?;
732 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
735 writer.write_all(&byte_utils::be64_to_array(self.counterparty_hash_commitment_number.len() as u64))?;
736 for (ref payment_hash, commitment_number) in self.counterparty_hash_commitment_number.iter() {
737 writer.write_all(&payment_hash.0[..])?;
738 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
741 if let Some(ref prev_holder_tx) = self.prev_holder_signed_commitment_tx {
742 writer.write_all(&[1; 1])?;
743 prev_holder_tx.write(writer)?;
745 writer.write_all(&[0; 1])?;
748 self.current_holder_commitment_tx.write(writer)?;
750 writer.write_all(&byte_utils::be48_to_array(self.current_counterparty_commitment_number))?;
751 writer.write_all(&byte_utils::be48_to_array(self.current_holder_commitment_number))?;
753 writer.write_all(&byte_utils::be64_to_array(self.payment_preimages.len() as u64))?;
754 for payment_preimage in self.payment_preimages.values() {
755 writer.write_all(&payment_preimage.0[..])?;
758 writer.write_all(&byte_utils::be64_to_array(self.pending_monitor_events.len() as u64))?;
759 for event in self.pending_monitor_events.iter() {
761 MonitorEvent::HTLCEvent(upd) => {
765 MonitorEvent::CommitmentTxBroadcasted(_) => 1u8.write(writer)?
769 writer.write_all(&byte_utils::be64_to_array(self.pending_events.len() as u64))?;
770 for event in self.pending_events.iter() {
771 event.write(writer)?;
774 self.best_block.block_hash().write(writer)?;
775 writer.write_all(&byte_utils::be32_to_array(self.best_block.height()))?;
777 writer.write_all(&byte_utils::be64_to_array(self.onchain_events_awaiting_threshold_conf.len() as u64))?;
778 for ref entry in self.onchain_events_awaiting_threshold_conf.iter() {
779 entry.write(writer)?;
782 (self.outputs_to_watch.len() as u64).write(writer)?;
783 for (txid, idx_scripts) in self.outputs_to_watch.iter() {
785 (idx_scripts.len() as u64).write(writer)?;
786 for (idx, script) in idx_scripts.iter() {
788 script.write(writer)?;
791 self.onchain_tx_handler.write(writer)?;
793 self.lockdown_from_offchain.write(writer)?;
794 self.holder_tx_signed.write(writer)?;
796 write_tlv_fields!(writer, {}, {});
802 impl<Signer: Sign> ChannelMonitor<Signer> {
803 pub(crate) fn new(secp_ctx: Secp256k1<secp256k1::All>, keys: Signer, shutdown_pubkey: &PublicKey,
804 on_counterparty_tx_csv: u16, destination_script: &Script, funding_info: (OutPoint, Script),
805 channel_parameters: &ChannelTransactionParameters,
806 funding_redeemscript: Script, channel_value_satoshis: u64,
807 commitment_transaction_number_obscure_factor: u64,
808 initial_holder_commitment_tx: HolderCommitmentTransaction,
809 best_block: BestBlock) -> ChannelMonitor<Signer> {
811 assert!(commitment_transaction_number_obscure_factor <= (1 << 48));
812 let our_channel_close_key_hash = WPubkeyHash::hash(&shutdown_pubkey.serialize());
813 let shutdown_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&our_channel_close_key_hash[..]).into_script();
814 let payment_key_hash = WPubkeyHash::hash(&keys.pubkeys().payment_point.serialize());
815 let counterparty_payment_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&payment_key_hash[..]).into_script();
817 let counterparty_channel_parameters = channel_parameters.counterparty_parameters.as_ref().unwrap();
818 let counterparty_delayed_payment_base_key = counterparty_channel_parameters.pubkeys.delayed_payment_basepoint;
819 let counterparty_htlc_base_key = counterparty_channel_parameters.pubkeys.htlc_basepoint;
820 let counterparty_tx_cache = CounterpartyCommitmentTransaction { counterparty_delayed_payment_base_key, counterparty_htlc_base_key, on_counterparty_tx_csv, per_htlc: HashMap::new() };
822 let channel_keys_id = keys.channel_keys_id();
823 let holder_revocation_basepoint = keys.pubkeys().revocation_basepoint;
825 // block for Rust 1.34 compat
826 let (holder_commitment_tx, current_holder_commitment_number) = {
827 let trusted_tx = initial_holder_commitment_tx.trust();
828 let txid = trusted_tx.txid();
830 let tx_keys = trusted_tx.keys();
831 let holder_commitment_tx = HolderSignedTx {
833 revocation_key: tx_keys.revocation_key,
834 a_htlc_key: tx_keys.broadcaster_htlc_key,
835 b_htlc_key: tx_keys.countersignatory_htlc_key,
836 delayed_payment_key: tx_keys.broadcaster_delayed_payment_key,
837 per_commitment_point: tx_keys.per_commitment_point,
838 feerate_per_kw: trusted_tx.feerate_per_kw(),
839 htlc_outputs: Vec::new(), // There are never any HTLCs in the initial commitment transactions
841 (holder_commitment_tx, trusted_tx.commitment_number())
844 let onchain_tx_handler =
845 OnchainTxHandler::new(destination_script.clone(), keys,
846 channel_parameters.clone(), initial_holder_commitment_tx, secp_ctx.clone());
848 let mut outputs_to_watch = HashMap::new();
849 outputs_to_watch.insert(funding_info.0.txid, vec![(funding_info.0.index as u32, funding_info.1.clone())]);
852 inner: Mutex::new(ChannelMonitorImpl {
854 commitment_transaction_number_obscure_factor,
856 destination_script: destination_script.clone(),
857 broadcasted_holder_revokable_script: None,
858 counterparty_payment_script,
862 holder_revocation_basepoint,
864 current_counterparty_commitment_txid: None,
865 prev_counterparty_commitment_txid: None,
867 counterparty_tx_cache,
868 funding_redeemscript,
869 channel_value_satoshis,
870 their_cur_revocation_points: None,
872 on_holder_tx_csv: counterparty_channel_parameters.selected_contest_delay,
874 commitment_secrets: CounterpartyCommitmentSecrets::new(),
875 counterparty_claimable_outpoints: HashMap::new(),
876 counterparty_commitment_txn_on_chain: HashMap::new(),
877 counterparty_hash_commitment_number: HashMap::new(),
879 prev_holder_signed_commitment_tx: None,
880 current_holder_commitment_tx: holder_commitment_tx,
881 current_counterparty_commitment_number: 1 << 48,
882 current_holder_commitment_number,
884 payment_preimages: HashMap::new(),
885 pending_monitor_events: Vec::new(),
886 pending_events: Vec::new(),
888 onchain_events_awaiting_threshold_conf: Vec::new(),
893 lockdown_from_offchain: false,
894 holder_tx_signed: false,
904 fn provide_secret(&self, idx: u64, secret: [u8; 32]) -> Result<(), MonitorUpdateError> {
905 self.inner.lock().unwrap().provide_secret(idx, secret)
908 /// Informs this monitor of the latest counterparty (ie non-broadcastable) commitment transaction.
909 /// The monitor watches for it to be broadcasted and then uses the HTLC information (and
910 /// possibly future revocation/preimage information) to claim outputs where possible.
911 /// We cache also the mapping hash:commitment number to lighten pruning of old preimages by watchtowers.
912 pub(crate) fn provide_latest_counterparty_commitment_tx<L: Deref>(
915 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
916 commitment_number: u64,
917 their_revocation_point: PublicKey,
919 ) where L::Target: Logger {
920 self.inner.lock().unwrap().provide_latest_counterparty_commitment_tx(
921 txid, htlc_outputs, commitment_number, their_revocation_point, logger)
925 fn provide_latest_holder_commitment_tx(
927 holder_commitment_tx: HolderCommitmentTransaction,
928 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
929 ) -> Result<(), MonitorUpdateError> {
930 self.inner.lock().unwrap().provide_latest_holder_commitment_tx(
931 holder_commitment_tx, htlc_outputs)
935 pub(crate) fn provide_payment_preimage<B: Deref, F: Deref, L: Deref>(
937 payment_hash: &PaymentHash,
938 payment_preimage: &PaymentPreimage,
943 B::Target: BroadcasterInterface,
944 F::Target: FeeEstimator,
947 self.inner.lock().unwrap().provide_payment_preimage(
948 payment_hash, payment_preimage, broadcaster, fee_estimator, logger)
951 pub(crate) fn broadcast_latest_holder_commitment_txn<B: Deref, L: Deref>(
956 B::Target: BroadcasterInterface,
959 self.inner.lock().unwrap().broadcast_latest_holder_commitment_txn(broadcaster, logger)
962 /// Updates a ChannelMonitor on the basis of some new information provided by the Channel
965 /// panics if the given update is not the next update by update_id.
966 pub fn update_monitor<B: Deref, F: Deref, L: Deref>(
968 updates: &ChannelMonitorUpdate,
972 ) -> Result<(), MonitorUpdateError>
974 B::Target: BroadcasterInterface,
975 F::Target: FeeEstimator,
978 self.inner.lock().unwrap().update_monitor(updates, broadcaster, fee_estimator, logger)
981 /// Gets the update_id from the latest ChannelMonitorUpdate which was applied to this
983 pub fn get_latest_update_id(&self) -> u64 {
984 self.inner.lock().unwrap().get_latest_update_id()
987 /// Gets the funding transaction outpoint of the channel this ChannelMonitor is monitoring for.
988 pub fn get_funding_txo(&self) -> (OutPoint, Script) {
989 self.inner.lock().unwrap().get_funding_txo().clone()
992 /// Gets a list of txids, with their output scripts (in the order they appear in the
993 /// transaction), which we must learn about spends of via block_connected().
994 pub fn get_outputs_to_watch(&self) -> Vec<(Txid, Vec<(u32, Script)>)> {
995 self.inner.lock().unwrap().get_outputs_to_watch()
996 .iter().map(|(txid, outputs)| (*txid, outputs.clone())).collect()
999 /// Loads the funding txo and outputs to watch into the given `chain::Filter` by repeatedly
1000 /// calling `chain::Filter::register_output` and `chain::Filter::register_tx` until all outputs
1001 /// have been registered.
1002 pub fn load_outputs_to_watch<F: Deref>(&self, filter: &F) where F::Target: chain::Filter {
1003 let lock = self.inner.lock().unwrap();
1004 filter.register_tx(&lock.get_funding_txo().0.txid, &lock.get_funding_txo().1);
1005 for (txid, outputs) in lock.get_outputs_to_watch().iter() {
1006 for (index, script_pubkey) in outputs.iter() {
1007 assert!(*index <= u16::max_value() as u32);
1008 filter.register_output(WatchedOutput {
1010 outpoint: OutPoint { txid: *txid, index: *index as u16 },
1011 script_pubkey: script_pubkey.clone(),
1017 /// Get the list of HTLCs who's status has been updated on chain. This should be called by
1018 /// ChannelManager via [`chain::Watch::release_pending_monitor_events`].
1019 pub fn get_and_clear_pending_monitor_events(&self) -> Vec<MonitorEvent> {
1020 self.inner.lock().unwrap().get_and_clear_pending_monitor_events()
1023 /// Gets the list of pending events which were generated by previous actions, clearing the list
1026 /// This is called by ChainMonitor::get_and_clear_pending_events() and is equivalent to
1027 /// EventsProvider::get_and_clear_pending_events() except that it requires &mut self as we do
1028 /// no internal locking in ChannelMonitors.
1029 pub fn get_and_clear_pending_events(&self) -> Vec<Event> {
1030 self.inner.lock().unwrap().get_and_clear_pending_events()
1033 pub(crate) fn get_min_seen_secret(&self) -> u64 {
1034 self.inner.lock().unwrap().get_min_seen_secret()
1037 pub(crate) fn get_cur_counterparty_commitment_number(&self) -> u64 {
1038 self.inner.lock().unwrap().get_cur_counterparty_commitment_number()
1041 pub(crate) fn get_cur_holder_commitment_number(&self) -> u64 {
1042 self.inner.lock().unwrap().get_cur_holder_commitment_number()
1045 /// Used by ChannelManager deserialization to broadcast the latest holder state if its copy of
1046 /// the Channel was out-of-date. You may use it to get a broadcastable holder toxic tx in case of
1047 /// fallen-behind, i.e when receiving a channel_reestablish with a proof that our counterparty side knows
1048 /// a higher revocation secret than the holder commitment number we are aware of. Broadcasting these
1049 /// transactions are UNSAFE, as they allow counterparty side to punish you. Nevertheless you may want to
1050 /// broadcast them if counterparty don't close channel with his higher commitment transaction after a
1051 /// substantial amount of time (a month or even a year) to get back funds. Best may be to contact
1052 /// out-of-band the other node operator to coordinate with him if option is available to you.
1053 /// In any-case, choice is up to the user.
1054 pub fn get_latest_holder_commitment_txn<L: Deref>(&self, logger: &L) -> Vec<Transaction>
1055 where L::Target: Logger {
1056 self.inner.lock().unwrap().get_latest_holder_commitment_txn(logger)
1059 /// Unsafe test-only version of get_latest_holder_commitment_txn used by our test framework
1060 /// to bypass HolderCommitmentTransaction state update lockdown after signature and generate
1061 /// revoked commitment transaction.
1062 #[cfg(any(test, feature = "unsafe_revoked_tx_signing"))]
1063 pub fn unsafe_get_latest_holder_commitment_txn<L: Deref>(&self, logger: &L) -> Vec<Transaction>
1064 where L::Target: Logger {
1065 self.inner.lock().unwrap().unsafe_get_latest_holder_commitment_txn(logger)
1068 /// Processes transactions in a newly connected block, which may result in any of the following:
1069 /// - update the monitor's state against resolved HTLCs
1070 /// - punish the counterparty in the case of seeing a revoked commitment transaction
1071 /// - force close the channel and claim/timeout incoming/outgoing HTLCs if near expiration
1072 /// - detect settled outputs for later spending
1073 /// - schedule and bump any in-flight claims
1075 /// Returns any new outputs to watch from `txdata`; after called, these are also included in
1076 /// [`get_outputs_to_watch`].
1078 /// [`get_outputs_to_watch`]: #method.get_outputs_to_watch
1079 pub fn block_connected<B: Deref, F: Deref, L: Deref>(
1081 header: &BlockHeader,
1082 txdata: &TransactionData,
1087 ) -> Vec<TransactionOutputs>
1089 B::Target: BroadcasterInterface,
1090 F::Target: FeeEstimator,
1093 self.inner.lock().unwrap().block_connected(
1094 header, txdata, height, broadcaster, fee_estimator, logger)
1097 /// Determines if the disconnected block contained any transactions of interest and updates
1099 pub fn block_disconnected<B: Deref, F: Deref, L: Deref>(
1101 header: &BlockHeader,
1107 B::Target: BroadcasterInterface,
1108 F::Target: FeeEstimator,
1111 self.inner.lock().unwrap().block_disconnected(
1112 header, height, broadcaster, fee_estimator, logger)
1115 /// Processes transactions confirmed in a block with the given header and height, returning new
1116 /// outputs to watch. See [`block_connected`] for details.
1118 /// Used instead of [`block_connected`] by clients that are notified of transactions rather than
1119 /// blocks. See [`chain::Confirm`] for calling expectations.
1121 /// [`block_connected`]: Self::block_connected
1122 pub fn transactions_confirmed<B: Deref, F: Deref, L: Deref>(
1124 header: &BlockHeader,
1125 txdata: &TransactionData,
1130 ) -> Vec<TransactionOutputs>
1132 B::Target: BroadcasterInterface,
1133 F::Target: FeeEstimator,
1136 self.inner.lock().unwrap().transactions_confirmed(
1137 header, txdata, height, broadcaster, fee_estimator, logger)
1140 /// Processes a transaction that was reorganized out of the chain.
1142 /// Used instead of [`block_disconnected`] by clients that are notified of transactions rather
1143 /// than blocks. See [`chain::Confirm`] for calling expectations.
1145 /// [`block_disconnected`]: Self::block_disconnected
1146 pub fn transaction_unconfirmed<B: Deref, F: Deref, L: Deref>(
1153 B::Target: BroadcasterInterface,
1154 F::Target: FeeEstimator,
1157 self.inner.lock().unwrap().transaction_unconfirmed(
1158 txid, broadcaster, fee_estimator, logger);
1161 /// Updates the monitor with the current best chain tip, returning new outputs to watch. See
1162 /// [`block_connected`] for details.
1164 /// Used instead of [`block_connected`] by clients that are notified of transactions rather than
1165 /// blocks. See [`chain::Confirm`] for calling expectations.
1167 /// [`block_connected`]: Self::block_connected
1168 pub fn best_block_updated<B: Deref, F: Deref, L: Deref>(
1170 header: &BlockHeader,
1175 ) -> Vec<TransactionOutputs>
1177 B::Target: BroadcasterInterface,
1178 F::Target: FeeEstimator,
1181 self.inner.lock().unwrap().best_block_updated(
1182 header, height, broadcaster, fee_estimator, logger)
1185 /// Returns the set of txids that should be monitored for re-organization out of the chain.
1186 pub fn get_relevant_txids(&self) -> Vec<Txid> {
1187 let inner = self.inner.lock().unwrap();
1188 let mut txids: Vec<Txid> = inner.onchain_events_awaiting_threshold_conf
1190 .map(|entry| entry.txid)
1191 .chain(inner.onchain_tx_handler.get_relevant_txids().into_iter())
1193 txids.sort_unstable();
1199 impl<Signer: Sign> ChannelMonitorImpl<Signer> {
1200 /// Inserts a revocation secret into this channel monitor. Prunes old preimages if neither
1201 /// needed by holder commitment transactions HTCLs nor by counterparty ones. Unless we haven't already seen
1202 /// counterparty commitment transaction's secret, they are de facto pruned (we can use revocation key).
1203 fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), MonitorUpdateError> {
1204 if let Err(()) = self.commitment_secrets.provide_secret(idx, secret) {
1205 return Err(MonitorUpdateError("Previous secret did not match new one"));
1208 // Prune HTLCs from the previous counterparty commitment tx so we don't generate failure/fulfill
1209 // events for now-revoked/fulfilled HTLCs.
1210 if let Some(txid) = self.prev_counterparty_commitment_txid.take() {
1211 for &mut (_, ref mut source) in self.counterparty_claimable_outpoints.get_mut(&txid).unwrap() {
1216 if !self.payment_preimages.is_empty() {
1217 let cur_holder_signed_commitment_tx = &self.current_holder_commitment_tx;
1218 let prev_holder_signed_commitment_tx = self.prev_holder_signed_commitment_tx.as_ref();
1219 let min_idx = self.get_min_seen_secret();
1220 let counterparty_hash_commitment_number = &mut self.counterparty_hash_commitment_number;
1222 self.payment_preimages.retain(|&k, _| {
1223 for &(ref htlc, _, _) in cur_holder_signed_commitment_tx.htlc_outputs.iter() {
1224 if k == htlc.payment_hash {
1228 if let Some(prev_holder_commitment_tx) = prev_holder_signed_commitment_tx {
1229 for &(ref htlc, _, _) in prev_holder_commitment_tx.htlc_outputs.iter() {
1230 if k == htlc.payment_hash {
1235 let contains = if let Some(cn) = counterparty_hash_commitment_number.get(&k) {
1242 counterparty_hash_commitment_number.remove(&k);
1251 pub(crate) fn provide_latest_counterparty_commitment_tx<L: Deref>(&mut self, txid: Txid, htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>, commitment_number: u64, their_revocation_point: PublicKey, logger: &L) where L::Target: Logger {
1252 // TODO: Encrypt the htlc_outputs data with the single-hash of the commitment transaction
1253 // so that a remote monitor doesn't learn anything unless there is a malicious close.
1254 // (only maybe, sadly we cant do the same for local info, as we need to be aware of
1256 for &(ref htlc, _) in &htlc_outputs {
1257 self.counterparty_hash_commitment_number.insert(htlc.payment_hash, commitment_number);
1260 log_trace!(logger, "Tracking new counterparty commitment transaction with txid {} at commitment number {} with {} HTLC outputs", txid, commitment_number, htlc_outputs.len());
1261 self.prev_counterparty_commitment_txid = self.current_counterparty_commitment_txid.take();
1262 self.current_counterparty_commitment_txid = Some(txid);
1263 self.counterparty_claimable_outpoints.insert(txid, htlc_outputs.clone());
1264 self.current_counterparty_commitment_number = commitment_number;
1265 //TODO: Merge this into the other per-counterparty-transaction output storage stuff
1266 match self.their_cur_revocation_points {
1267 Some(old_points) => {
1268 if old_points.0 == commitment_number + 1 {
1269 self.their_cur_revocation_points = Some((old_points.0, old_points.1, Some(their_revocation_point)));
1270 } else if old_points.0 == commitment_number + 2 {
1271 if let Some(old_second_point) = old_points.2 {
1272 self.their_cur_revocation_points = Some((old_points.0 - 1, old_second_point, Some(their_revocation_point)));
1274 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1277 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1281 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1284 let mut htlcs = Vec::with_capacity(htlc_outputs.len());
1285 for htlc in htlc_outputs {
1286 if htlc.0.transaction_output_index.is_some() {
1290 self.counterparty_tx_cache.per_htlc.insert(txid, htlcs);
1293 /// Informs this monitor of the latest holder (ie broadcastable) commitment transaction. The
1294 /// monitor watches for timeouts and may broadcast it if we approach such a timeout. Thus, it
1295 /// is important that any clones of this channel monitor (including remote clones) by kept
1296 /// up-to-date as our holder commitment transaction is updated.
1297 /// Panics if set_on_holder_tx_csv has never been called.
1298 fn provide_latest_holder_commitment_tx(&mut self, holder_commitment_tx: HolderCommitmentTransaction, htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>) -> Result<(), MonitorUpdateError> {
1299 // block for Rust 1.34 compat
1300 let mut new_holder_commitment_tx = {
1301 let trusted_tx = holder_commitment_tx.trust();
1302 let txid = trusted_tx.txid();
1303 let tx_keys = trusted_tx.keys();
1304 self.current_holder_commitment_number = trusted_tx.commitment_number();
1307 revocation_key: tx_keys.revocation_key,
1308 a_htlc_key: tx_keys.broadcaster_htlc_key,
1309 b_htlc_key: tx_keys.countersignatory_htlc_key,
1310 delayed_payment_key: tx_keys.broadcaster_delayed_payment_key,
1311 per_commitment_point: tx_keys.per_commitment_point,
1312 feerate_per_kw: trusted_tx.feerate_per_kw(),
1316 self.onchain_tx_handler.provide_latest_holder_tx(holder_commitment_tx);
1317 mem::swap(&mut new_holder_commitment_tx, &mut self.current_holder_commitment_tx);
1318 self.prev_holder_signed_commitment_tx = Some(new_holder_commitment_tx);
1319 if self.holder_tx_signed {
1320 return Err(MonitorUpdateError("Latest holder commitment signed has already been signed, update is rejected"));
1325 /// Provides a payment_hash->payment_preimage mapping. Will be automatically pruned when all
1326 /// commitment_tx_infos which contain the payment hash have been revoked.
1327 fn provide_payment_preimage<B: Deref, F: Deref, L: Deref>(&mut self, payment_hash: &PaymentHash, payment_preimage: &PaymentPreimage, broadcaster: &B, fee_estimator: &F, logger: &L)
1328 where B::Target: BroadcasterInterface,
1329 F::Target: FeeEstimator,
1332 self.payment_preimages.insert(payment_hash.clone(), payment_preimage.clone());
1334 // If the channel is force closed, try to claim the output from this preimage.
1335 // First check if a counterparty commitment transaction has been broadcasted:
1336 macro_rules! claim_htlcs {
1337 ($commitment_number: expr, $txid: expr) => {
1338 let htlc_claim_reqs = self.get_counterparty_htlc_output_claim_reqs($commitment_number, $txid, None);
1339 self.onchain_tx_handler.update_claims_view(&Vec::new(), htlc_claim_reqs, self.best_block.height(), broadcaster, fee_estimator, logger);
1342 if let Some(txid) = self.current_counterparty_commitment_txid {
1343 if let Some(commitment_number) = self.counterparty_commitment_txn_on_chain.get(&txid) {
1344 claim_htlcs!(*commitment_number, txid);
1348 if let Some(txid) = self.prev_counterparty_commitment_txid {
1349 if let Some(commitment_number) = self.counterparty_commitment_txn_on_chain.get(&txid) {
1350 claim_htlcs!(*commitment_number, txid);
1355 // Then if a holder commitment transaction has been seen on-chain, broadcast transactions
1356 // claiming the HTLC output from each of the holder commitment transactions.
1357 // Note that we can't just use `self.holder_tx_signed`, because that only covers the case where
1358 // *we* sign a holder commitment transaction, not when e.g. a watchtower broadcasts one of our
1359 // holder commitment transactions.
1360 if self.broadcasted_holder_revokable_script.is_some() {
1361 let (claim_reqs, _) = self.get_broadcasted_holder_claims(&self.current_holder_commitment_tx, 0);
1362 self.onchain_tx_handler.update_claims_view(&Vec::new(), claim_reqs, self.best_block.height(), broadcaster, fee_estimator, logger);
1363 if let Some(ref tx) = self.prev_holder_signed_commitment_tx {
1364 let (claim_reqs, _) = self.get_broadcasted_holder_claims(&tx, 0);
1365 self.onchain_tx_handler.update_claims_view(&Vec::new(), claim_reqs, self.best_block.height(), broadcaster, fee_estimator, logger);
1370 pub(crate) fn broadcast_latest_holder_commitment_txn<B: Deref, L: Deref>(&mut self, broadcaster: &B, logger: &L)
1371 where B::Target: BroadcasterInterface,
1374 for tx in self.get_latest_holder_commitment_txn(logger).iter() {
1375 log_info!(logger, "Broadcasting local {}", log_tx!(tx));
1376 broadcaster.broadcast_transaction(tx);
1378 self.pending_monitor_events.push(MonitorEvent::CommitmentTxBroadcasted(self.funding_info.0));
1381 pub fn update_monitor<B: Deref, F: Deref, L: Deref>(&mut self, updates: &ChannelMonitorUpdate, broadcaster: &B, fee_estimator: &F, logger: &L) -> Result<(), MonitorUpdateError>
1382 where B::Target: BroadcasterInterface,
1383 F::Target: FeeEstimator,
1386 // ChannelMonitor updates may be applied after force close if we receive a
1387 // preimage for a broadcasted commitment transaction HTLC output that we'd
1388 // like to claim on-chain. If this is the case, we no longer have guaranteed
1389 // access to the monitor's update ID, so we use a sentinel value instead.
1390 if updates.update_id == CLOSED_CHANNEL_UPDATE_ID {
1391 match updates.updates[0] {
1392 ChannelMonitorUpdateStep::PaymentPreimage { .. } => {},
1393 _ => panic!("Attempted to apply post-force-close ChannelMonitorUpdate that wasn't providing a payment preimage"),
1395 assert_eq!(updates.updates.len(), 1);
1396 } else if self.latest_update_id + 1 != updates.update_id {
1397 panic!("Attempted to apply ChannelMonitorUpdates out of order, check the update_id before passing an update to update_monitor!");
1399 for update in updates.updates.iter() {
1401 ChannelMonitorUpdateStep::LatestHolderCommitmentTXInfo { commitment_tx, htlc_outputs } => {
1402 log_trace!(logger, "Updating ChannelMonitor with latest holder commitment transaction info");
1403 if self.lockdown_from_offchain { panic!(); }
1404 self.provide_latest_holder_commitment_tx(commitment_tx.clone(), htlc_outputs.clone())?
1406 ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo { commitment_txid, htlc_outputs, commitment_number, their_revocation_point } => {
1407 log_trace!(logger, "Updating ChannelMonitor with latest counterparty commitment transaction info");
1408 self.provide_latest_counterparty_commitment_tx(*commitment_txid, htlc_outputs.clone(), *commitment_number, *their_revocation_point, logger)
1410 ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage } => {
1411 log_trace!(logger, "Updating ChannelMonitor with payment preimage");
1412 self.provide_payment_preimage(&PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()), &payment_preimage, broadcaster, fee_estimator, logger)
1414 ChannelMonitorUpdateStep::CommitmentSecret { idx, secret } => {
1415 log_trace!(logger, "Updating ChannelMonitor with commitment secret");
1416 self.provide_secret(*idx, *secret)?
1418 ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast } => {
1419 log_trace!(logger, "Updating ChannelMonitor: channel force closed, should broadcast: {}", should_broadcast);
1420 self.lockdown_from_offchain = true;
1421 if *should_broadcast {
1422 self.broadcast_latest_holder_commitment_txn(broadcaster, logger);
1423 } else if !self.holder_tx_signed {
1424 log_error!(logger, "You have a toxic holder commitment transaction avaible in channel monitor, read comment in ChannelMonitor::get_latest_holder_commitment_txn to be informed of manual action to take");
1426 // If we generated a MonitorEvent::CommitmentTxBroadcasted, the ChannelManager
1427 // will still give us a ChannelForceClosed event with !should_broadcast, but we
1428 // shouldn't print the scary warning above.
1429 log_info!(logger, "Channel off-chain state closed after we broadcasted our latest commitment transaction.");
1434 self.latest_update_id = updates.update_id;
1438 pub fn get_latest_update_id(&self) -> u64 {
1439 self.latest_update_id
1442 pub fn get_funding_txo(&self) -> &(OutPoint, Script) {
1446 pub fn get_outputs_to_watch(&self) -> &HashMap<Txid, Vec<(u32, Script)>> {
1447 // If we've detected a counterparty commitment tx on chain, we must include it in the set
1448 // of outputs to watch for spends of, otherwise we're likely to lose user funds. Because
1449 // its trivial to do, double-check that here.
1450 for (txid, _) in self.counterparty_commitment_txn_on_chain.iter() {
1451 self.outputs_to_watch.get(txid).expect("Counterparty commitment txn which have been broadcast should have outputs registered");
1453 &self.outputs_to_watch
1456 pub fn get_and_clear_pending_monitor_events(&mut self) -> Vec<MonitorEvent> {
1457 let mut ret = Vec::new();
1458 mem::swap(&mut ret, &mut self.pending_monitor_events);
1462 pub fn get_and_clear_pending_events(&mut self) -> Vec<Event> {
1463 let mut ret = Vec::new();
1464 mem::swap(&mut ret, &mut self.pending_events);
1468 /// Can only fail if idx is < get_min_seen_secret
1469 fn get_secret(&self, idx: u64) -> Option<[u8; 32]> {
1470 self.commitment_secrets.get_secret(idx)
1473 pub(crate) fn get_min_seen_secret(&self) -> u64 {
1474 self.commitment_secrets.get_min_seen_secret()
1477 pub(crate) fn get_cur_counterparty_commitment_number(&self) -> u64 {
1478 self.current_counterparty_commitment_number
1481 pub(crate) fn get_cur_holder_commitment_number(&self) -> u64 {
1482 self.current_holder_commitment_number
1485 /// Attempts to claim a counterparty commitment transaction's outputs using the revocation key and
1486 /// data in counterparty_claimable_outpoints. Will directly claim any HTLC outputs which expire at a
1487 /// height > height + CLTV_SHARED_CLAIM_BUFFER. In any case, will install monitoring for
1488 /// HTLC-Success/HTLC-Timeout transactions.
1489 /// Return updates for HTLC pending in the channel and failed automatically by the broadcast of
1490 /// revoked counterparty commitment tx
1491 fn check_spend_counterparty_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) -> (Vec<PackageTemplate>, TransactionOutputs) where L::Target: Logger {
1492 // Most secp and related errors trying to create keys means we have no hope of constructing
1493 // a spend transaction...so we return no transactions to broadcast
1494 let mut claimable_outpoints = Vec::new();
1495 let mut watch_outputs = Vec::new();
1497 let commitment_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
1498 let per_commitment_option = self.counterparty_claimable_outpoints.get(&commitment_txid);
1500 macro_rules! ignore_error {
1501 ( $thing : expr ) => {
1504 Err(_) => return (claimable_outpoints, (commitment_txid, watch_outputs))
1509 let commitment_number = 0xffffffffffff - ((((tx.input[0].sequence as u64 & 0xffffff) << 3*8) | (tx.lock_time as u64 & 0xffffff)) ^ self.commitment_transaction_number_obscure_factor);
1510 if commitment_number >= self.get_min_seen_secret() {
1511 let secret = self.get_secret(commitment_number).unwrap();
1512 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
1513 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1514 let revocation_pubkey = ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &self.holder_revocation_basepoint));
1515 let delayed_key = ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key), &self.counterparty_tx_cache.counterparty_delayed_payment_base_key));
1517 let revokeable_redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.counterparty_tx_cache.on_counterparty_tx_csv, &delayed_key);
1518 let revokeable_p2wsh = revokeable_redeemscript.to_v0_p2wsh();
1520 // First, process non-htlc outputs (to_holder & to_counterparty)
1521 for (idx, outp) in tx.output.iter().enumerate() {
1522 if outp.script_pubkey == revokeable_p2wsh {
1523 let revk_outp = RevokedOutput::build(per_commitment_point, self.counterparty_tx_cache.counterparty_delayed_payment_base_key, self.counterparty_tx_cache.counterparty_htlc_base_key, per_commitment_key, outp.value, self.counterparty_tx_cache.on_counterparty_tx_csv);
1524 let justice_package = PackageTemplate::build_package(commitment_txid, idx as u32, PackageSolvingData::RevokedOutput(revk_outp), height + self.counterparty_tx_cache.on_counterparty_tx_csv as u32, true, height);
1525 claimable_outpoints.push(justice_package);
1529 // Then, try to find revoked htlc outputs
1530 if let Some(ref per_commitment_data) = per_commitment_option {
1531 for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
1532 if let Some(transaction_output_index) = htlc.transaction_output_index {
1533 if transaction_output_index as usize >= tx.output.len() ||
1534 tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
1535 return (claimable_outpoints, (commitment_txid, watch_outputs)); // Corrupted per_commitment_data, fuck this user
1537 let revk_htlc_outp = RevokedHTLCOutput::build(per_commitment_point, self.counterparty_tx_cache.counterparty_delayed_payment_base_key, self.counterparty_tx_cache.counterparty_htlc_base_key, per_commitment_key, htlc.amount_msat / 1000, htlc.clone());
1538 let justice_package = PackageTemplate::build_package(commitment_txid, transaction_output_index, PackageSolvingData::RevokedHTLCOutput(revk_htlc_outp), htlc.cltv_expiry, true, height);
1539 claimable_outpoints.push(justice_package);
1544 // Last, track onchain revoked commitment transaction and fail backward outgoing HTLCs as payment path is broken
1545 if !claimable_outpoints.is_empty() || per_commitment_option.is_some() { // ie we're confident this is actually ours
1546 // We're definitely a counterparty commitment transaction!
1547 log_trace!(logger, "Got broadcast of revoked counterparty commitment transaction, going to generate general spend tx with {} inputs", claimable_outpoints.len());
1548 for (idx, outp) in tx.output.iter().enumerate() {
1549 watch_outputs.push((idx as u32, outp.clone()));
1551 self.counterparty_commitment_txn_on_chain.insert(commitment_txid, commitment_number);
1553 macro_rules! check_htlc_fails {
1554 ($txid: expr, $commitment_tx: expr) => {
1555 if let Some(ref outpoints) = self.counterparty_claimable_outpoints.get($txid) {
1556 for &(ref htlc, ref source_option) in outpoints.iter() {
1557 if let &Some(ref source) = source_option {
1558 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| {
1559 if entry.height != height { return true; }
1561 OnchainEvent::HTLCUpdate { source: ref update_source, .. } => {
1562 *update_source != **source
1567 let entry = OnchainEventEntry {
1570 event: OnchainEvent::HTLCUpdate {
1571 source: (**source).clone(),
1572 payment_hash: htlc.payment_hash.clone(),
1575 log_info!(logger, "Failing HTLC with payment_hash {} from {} counterparty commitment tx due to broadcast of revoked counterparty commitment transaction, waiting for confirmation (at height {})", log_bytes!(htlc.payment_hash.0), $commitment_tx, entry.confirmation_threshold());
1576 self.onchain_events_awaiting_threshold_conf.push(entry);
1582 if let Some(ref txid) = self.current_counterparty_commitment_txid {
1583 check_htlc_fails!(txid, "current");
1585 if let Some(ref txid) = self.prev_counterparty_commitment_txid {
1586 check_htlc_fails!(txid, "counterparty");
1588 // No need to check holder commitment txn, symmetric HTLCSource must be present as per-htlc data on counterparty commitment tx
1590 } else if let Some(per_commitment_data) = per_commitment_option {
1591 // While this isn't useful yet, there is a potential race where if a counterparty
1592 // revokes a state at the same time as the commitment transaction for that state is
1593 // confirmed, and the watchtower receives the block before the user, the user could
1594 // upload a new ChannelMonitor with the revocation secret but the watchtower has
1595 // already processed the block, resulting in the counterparty_commitment_txn_on_chain entry
1596 // not being generated by the above conditional. Thus, to be safe, we go ahead and
1598 for (idx, outp) in tx.output.iter().enumerate() {
1599 watch_outputs.push((idx as u32, outp.clone()));
1601 self.counterparty_commitment_txn_on_chain.insert(commitment_txid, commitment_number);
1603 log_trace!(logger, "Got broadcast of non-revoked counterparty commitment transaction {}", commitment_txid);
1605 macro_rules! check_htlc_fails {
1606 ($txid: expr, $commitment_tx: expr, $id: tt) => {
1607 if let Some(ref latest_outpoints) = self.counterparty_claimable_outpoints.get($txid) {
1608 $id: for &(ref htlc, ref source_option) in latest_outpoints.iter() {
1609 if let &Some(ref source) = source_option {
1610 // Check if the HTLC is present in the commitment transaction that was
1611 // broadcast, but not if it was below the dust limit, which we should
1612 // fail backwards immediately as there is no way for us to learn the
1613 // payment_preimage.
1614 // Note that if the dust limit were allowed to change between
1615 // commitment transactions we'd want to be check whether *any*
1616 // broadcastable commitment transaction has the HTLC in it, but it
1617 // cannot currently change after channel initialization, so we don't
1619 for &(ref broadcast_htlc, ref broadcast_source) in per_commitment_data.iter() {
1620 if broadcast_htlc.transaction_output_index.is_some() && Some(source) == broadcast_source.as_ref() {
1624 log_trace!(logger, "Failing HTLC with payment_hash {} from {} counterparty commitment tx due to broadcast of counterparty commitment transaction", log_bytes!(htlc.payment_hash.0), $commitment_tx);
1625 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| {
1626 if entry.height != height { return true; }
1628 OnchainEvent::HTLCUpdate { source: ref update_source, .. } => {
1629 *update_source != **source
1634 self.onchain_events_awaiting_threshold_conf.push(OnchainEventEntry {
1637 event: OnchainEvent::HTLCUpdate {
1638 source: (**source).clone(),
1639 payment_hash: htlc.payment_hash.clone(),
1647 if let Some(ref txid) = self.current_counterparty_commitment_txid {
1648 check_htlc_fails!(txid, "current", 'current_loop);
1650 if let Some(ref txid) = self.prev_counterparty_commitment_txid {
1651 check_htlc_fails!(txid, "previous", 'prev_loop);
1654 let htlc_claim_reqs = self.get_counterparty_htlc_output_claim_reqs(commitment_number, commitment_txid, Some(tx));
1655 for req in htlc_claim_reqs {
1656 claimable_outpoints.push(req);
1660 (claimable_outpoints, (commitment_txid, watch_outputs))
1663 fn get_counterparty_htlc_output_claim_reqs(&self, commitment_number: u64, commitment_txid: Txid, tx: Option<&Transaction>) -> Vec<PackageTemplate> {
1664 let mut claimable_outpoints = Vec::new();
1665 if let Some(htlc_outputs) = self.counterparty_claimable_outpoints.get(&commitment_txid) {
1666 if let Some(revocation_points) = self.their_cur_revocation_points {
1667 let revocation_point_option =
1668 // If the counterparty commitment tx is the latest valid state, use their latest
1669 // per-commitment point
1670 if revocation_points.0 == commitment_number { Some(&revocation_points.1) }
1671 else if let Some(point) = revocation_points.2.as_ref() {
1672 // If counterparty commitment tx is the state previous to the latest valid state, use
1673 // their previous per-commitment point (non-atomicity of revocation means it's valid for
1674 // them to temporarily have two valid commitment txns from our viewpoint)
1675 if revocation_points.0 == commitment_number + 1 { Some(point) } else { None }
1677 if let Some(revocation_point) = revocation_point_option {
1678 for (_, &(ref htlc, _)) in htlc_outputs.iter().enumerate() {
1679 if let Some(transaction_output_index) = htlc.transaction_output_index {
1680 if let Some(transaction) = tx {
1681 if transaction_output_index as usize >= transaction.output.len() ||
1682 transaction.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
1683 return claimable_outpoints; // Corrupted per_commitment_data, fuck this user
1686 let preimage = if htlc.offered { if let Some(p) = self.payment_preimages.get(&htlc.payment_hash) { Some(*p) } else { None } } else { None };
1687 if preimage.is_some() || !htlc.offered {
1688 let counterparty_htlc_outp = if htlc.offered { PackageSolvingData::CounterpartyOfferedHTLCOutput(CounterpartyOfferedHTLCOutput::build(*revocation_point, self.counterparty_tx_cache.counterparty_delayed_payment_base_key, self.counterparty_tx_cache.counterparty_htlc_base_key, preimage.unwrap(), htlc.clone())) } else { PackageSolvingData::CounterpartyReceivedHTLCOutput(CounterpartyReceivedHTLCOutput::build(*revocation_point, self.counterparty_tx_cache.counterparty_delayed_payment_base_key, self.counterparty_tx_cache.counterparty_htlc_base_key, htlc.clone())) };
1689 let aggregation = if !htlc.offered { false } else { true };
1690 let counterparty_package = PackageTemplate::build_package(commitment_txid, transaction_output_index, counterparty_htlc_outp, htlc.cltv_expiry,aggregation, 0);
1691 claimable_outpoints.push(counterparty_package);
1701 /// Attempts to claim a counterparty HTLC-Success/HTLC-Timeout's outputs using the revocation key
1702 fn check_spend_counterparty_htlc<L: Deref>(&mut self, tx: &Transaction, commitment_number: u64, height: u32, logger: &L) -> (Vec<PackageTemplate>, Option<TransactionOutputs>) where L::Target: Logger {
1703 let htlc_txid = tx.txid();
1704 if tx.input.len() != 1 || tx.output.len() != 1 || tx.input[0].witness.len() != 5 {
1705 return (Vec::new(), None)
1708 macro_rules! ignore_error {
1709 ( $thing : expr ) => {
1712 Err(_) => return (Vec::new(), None)
1717 let secret = if let Some(secret) = self.get_secret(commitment_number) { secret } else { return (Vec::new(), None); };
1718 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
1719 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1721 log_trace!(logger, "Counterparty HTLC broadcast {}:{}", htlc_txid, 0);
1722 let revk_outp = RevokedOutput::build(per_commitment_point, self.counterparty_tx_cache.counterparty_delayed_payment_base_key, self.counterparty_tx_cache.counterparty_htlc_base_key, per_commitment_key, tx.output[0].value, self.counterparty_tx_cache.on_counterparty_tx_csv);
1723 let justice_package = PackageTemplate::build_package(htlc_txid, 0, PackageSolvingData::RevokedOutput(revk_outp), height + self.counterparty_tx_cache.on_counterparty_tx_csv as u32, true, height);
1724 let claimable_outpoints = vec!(justice_package);
1725 let outputs = vec![(0, tx.output[0].clone())];
1726 (claimable_outpoints, Some((htlc_txid, outputs)))
1729 // Returns (1) `PackageTemplate`s that can be given to the OnChainTxHandler, so that the handler can
1730 // broadcast transactions claiming holder HTLC commitment outputs and (2) a holder revokable
1731 // script so we can detect whether a holder transaction has been seen on-chain.
1732 fn get_broadcasted_holder_claims(&self, holder_tx: &HolderSignedTx, height: u32) -> (Vec<PackageTemplate>, Option<(Script, PublicKey, PublicKey)>) {
1733 let mut claim_requests = Vec::with_capacity(holder_tx.htlc_outputs.len());
1735 let redeemscript = chan_utils::get_revokeable_redeemscript(&holder_tx.revocation_key, self.on_holder_tx_csv, &holder_tx.delayed_payment_key);
1736 let broadcasted_holder_revokable_script = Some((redeemscript.to_v0_p2wsh(), holder_tx.per_commitment_point.clone(), holder_tx.revocation_key.clone()));
1738 for &(ref htlc, _, _) in holder_tx.htlc_outputs.iter() {
1739 if let Some(transaction_output_index) = htlc.transaction_output_index {
1740 let htlc_output = if htlc.offered {
1741 HolderHTLCOutput::build_offered(htlc.amount_msat, htlc.cltv_expiry)
1743 let payment_preimage = if let Some(preimage) = self.payment_preimages.get(&htlc.payment_hash) {
1746 // We can't build an HTLC-Success transaction without the preimage
1749 HolderHTLCOutput::build_accepted(payment_preimage, htlc.amount_msat)
1751 let htlc_package = PackageTemplate::build_package(holder_tx.txid, transaction_output_index, PackageSolvingData::HolderHTLCOutput(htlc_output), height, false, height);
1752 claim_requests.push(htlc_package);
1756 (claim_requests, broadcasted_holder_revokable_script)
1759 // Returns holder HTLC outputs to watch and react to in case of spending.
1760 fn get_broadcasted_holder_watch_outputs(&self, holder_tx: &HolderSignedTx, commitment_tx: &Transaction) -> Vec<(u32, TxOut)> {
1761 let mut watch_outputs = Vec::with_capacity(holder_tx.htlc_outputs.len());
1762 for &(ref htlc, _, _) in holder_tx.htlc_outputs.iter() {
1763 if let Some(transaction_output_index) = htlc.transaction_output_index {
1764 watch_outputs.push((transaction_output_index, commitment_tx.output[transaction_output_index as usize].clone()));
1770 /// Attempts to claim any claimable HTLCs in a commitment transaction which was not (yet)
1771 /// revoked using data in holder_claimable_outpoints.
1772 /// Should not be used if check_spend_revoked_transaction succeeds.
1773 fn check_spend_holder_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) -> (Vec<PackageTemplate>, TransactionOutputs) where L::Target: Logger {
1774 let commitment_txid = tx.txid();
1775 let mut claim_requests = Vec::new();
1776 let mut watch_outputs = Vec::new();
1778 macro_rules! wait_threshold_conf {
1779 ($source: expr, $commitment_tx: expr, $payment_hash: expr) => {
1780 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| {
1781 if entry.height != height { return true; }
1783 OnchainEvent::HTLCUpdate { source: ref update_source, .. } => {
1784 *update_source != $source
1789 let entry = OnchainEventEntry {
1790 txid: commitment_txid,
1792 event: OnchainEvent::HTLCUpdate { source: $source, payment_hash: $payment_hash },
1794 log_trace!(logger, "Failing HTLC with payment_hash {} from {} holder commitment tx due to broadcast of transaction, waiting confirmation (at height{})", log_bytes!($payment_hash.0), $commitment_tx, entry.confirmation_threshold());
1795 self.onchain_events_awaiting_threshold_conf.push(entry);
1799 macro_rules! append_onchain_update {
1800 ($updates: expr, $to_watch: expr) => {
1801 claim_requests = $updates.0;
1802 self.broadcasted_holder_revokable_script = $updates.1;
1803 watch_outputs.append(&mut $to_watch);
1807 // HTLCs set may differ between last and previous holder commitment txn, in case of one them hitting chain, ensure we cancel all HTLCs backward
1808 let mut is_holder_tx = false;
1810 if self.current_holder_commitment_tx.txid == commitment_txid {
1811 is_holder_tx = true;
1812 log_trace!(logger, "Got latest holder commitment tx broadcast, searching for available HTLCs to claim");
1813 let res = self.get_broadcasted_holder_claims(&self.current_holder_commitment_tx, height);
1814 let mut to_watch = self.get_broadcasted_holder_watch_outputs(&self.current_holder_commitment_tx, tx);
1815 append_onchain_update!(res, to_watch);
1816 } else if let &Some(ref holder_tx) = &self.prev_holder_signed_commitment_tx {
1817 if holder_tx.txid == commitment_txid {
1818 is_holder_tx = true;
1819 log_trace!(logger, "Got previous holder commitment tx broadcast, searching for available HTLCs to claim");
1820 let res = self.get_broadcasted_holder_claims(holder_tx, height);
1821 let mut to_watch = self.get_broadcasted_holder_watch_outputs(holder_tx, tx);
1822 append_onchain_update!(res, to_watch);
1826 macro_rules! fail_dust_htlcs_after_threshold_conf {
1827 ($holder_tx: expr) => {
1828 for &(ref htlc, _, ref source) in &$holder_tx.htlc_outputs {
1829 if htlc.transaction_output_index.is_none() {
1830 if let &Some(ref source) = source {
1831 wait_threshold_conf!(source.clone(), "lastest", htlc.payment_hash.clone());
1839 fail_dust_htlcs_after_threshold_conf!(self.current_holder_commitment_tx);
1840 if let &Some(ref holder_tx) = &self.prev_holder_signed_commitment_tx {
1841 fail_dust_htlcs_after_threshold_conf!(holder_tx);
1845 (claim_requests, (commitment_txid, watch_outputs))
1848 pub fn get_latest_holder_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
1849 log_trace!(logger, "Getting signed latest holder commitment transaction!");
1850 self.holder_tx_signed = true;
1851 let commitment_tx = self.onchain_tx_handler.get_fully_signed_holder_tx(&self.funding_redeemscript);
1852 let txid = commitment_tx.txid();
1853 let mut holder_transactions = vec![commitment_tx];
1854 for htlc in self.current_holder_commitment_tx.htlc_outputs.iter() {
1855 if let Some(vout) = htlc.0.transaction_output_index {
1856 let preimage = if !htlc.0.offered {
1857 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
1858 // We can't build an HTLC-Success transaction without the preimage
1861 } else if htlc.0.cltv_expiry > self.best_block.height() + 1 {
1862 // Don't broadcast HTLC-Timeout transactions immediately as they don't meet the
1863 // current locktime requirements on-chain. We will broadcast them in
1864 // `block_confirmed` when `would_broadcast_at_height` returns true.
1865 // Note that we add + 1 as transactions are broadcastable when they can be
1866 // confirmed in the next block.
1869 if let Some(htlc_tx) = self.onchain_tx_handler.get_fully_signed_htlc_tx(
1870 &::bitcoin::OutPoint { txid, vout }, &preimage) {
1871 holder_transactions.push(htlc_tx);
1875 // We throw away the generated waiting_first_conf data as we aren't (yet) confirmed and we don't actually know what the caller wants to do.
1876 // The data will be re-generated and tracked in check_spend_holder_transaction if we get a confirmation.
1880 #[cfg(any(test,feature = "unsafe_revoked_tx_signing"))]
1881 /// Note that this includes possibly-locktimed-in-the-future transactions!
1882 fn unsafe_get_latest_holder_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
1883 log_trace!(logger, "Getting signed copy of latest holder commitment transaction!");
1884 let commitment_tx = self.onchain_tx_handler.get_fully_signed_copy_holder_tx(&self.funding_redeemscript);
1885 let txid = commitment_tx.txid();
1886 let mut holder_transactions = vec![commitment_tx];
1887 for htlc in self.current_holder_commitment_tx.htlc_outputs.iter() {
1888 if let Some(vout) = htlc.0.transaction_output_index {
1889 let preimage = if !htlc.0.offered {
1890 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
1891 // We can't build an HTLC-Success transaction without the preimage
1895 if let Some(htlc_tx) = self.onchain_tx_handler.unsafe_get_fully_signed_htlc_tx(
1896 &::bitcoin::OutPoint { txid, vout }, &preimage) {
1897 holder_transactions.push(htlc_tx);
1904 pub fn block_connected<B: Deref, F: Deref, L: Deref>(&mut self, header: &BlockHeader, txdata: &TransactionData, height: u32, broadcaster: B, fee_estimator: F, logger: L) -> Vec<TransactionOutputs>
1905 where B::Target: BroadcasterInterface,
1906 F::Target: FeeEstimator,
1909 let block_hash = header.block_hash();
1910 log_trace!(logger, "New best block {} at height {}", block_hash, height);
1911 self.best_block = BestBlock::new(block_hash, height);
1913 self.transactions_confirmed(header, txdata, height, broadcaster, fee_estimator, logger)
1916 fn best_block_updated<B: Deref, F: Deref, L: Deref>(
1918 header: &BlockHeader,
1923 ) -> Vec<TransactionOutputs>
1925 B::Target: BroadcasterInterface,
1926 F::Target: FeeEstimator,
1929 let block_hash = header.block_hash();
1930 log_trace!(logger, "New best block {} at height {}", block_hash, height);
1932 if height > self.best_block.height() {
1933 self.best_block = BestBlock::new(block_hash, height);
1934 self.block_confirmed(height, vec![], vec![], vec![], broadcaster, fee_estimator, logger)
1936 self.best_block = BestBlock::new(block_hash, height);
1937 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| entry.height <= height);
1938 self.onchain_tx_handler.block_disconnected(height + 1, broadcaster, fee_estimator, logger);
1943 fn transactions_confirmed<B: Deref, F: Deref, L: Deref>(
1945 header: &BlockHeader,
1946 txdata: &TransactionData,
1951 ) -> Vec<TransactionOutputs>
1953 B::Target: BroadcasterInterface,
1954 F::Target: FeeEstimator,
1957 let txn_matched = self.filter_block(txdata);
1958 for tx in &txn_matched {
1959 let mut output_val = 0;
1960 for out in tx.output.iter() {
1961 if out.value > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
1962 output_val += out.value;
1963 if output_val > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
1967 let block_hash = header.block_hash();
1968 log_trace!(logger, "Block {} at height {} connected with {} txn matched", block_hash, height, txn_matched.len());
1970 let mut watch_outputs = Vec::new();
1971 let mut claimable_outpoints = Vec::new();
1972 for tx in &txn_matched {
1973 if tx.input.len() == 1 {
1974 // Assuming our keys were not leaked (in which case we're screwed no matter what),
1975 // commitment transactions and HTLC transactions will all only ever have one input,
1976 // which is an easy way to filter out any potential non-matching txn for lazy
1978 let prevout = &tx.input[0].previous_output;
1979 if prevout.txid == self.funding_info.0.txid && prevout.vout == self.funding_info.0.index as u32 {
1980 if (tx.input[0].sequence >> 8*3) as u8 == 0x80 && (tx.lock_time >> 8*3) as u8 == 0x20 {
1981 let (mut new_outpoints, new_outputs) = self.check_spend_counterparty_transaction(&tx, height, &logger);
1982 if !new_outputs.1.is_empty() {
1983 watch_outputs.push(new_outputs);
1985 if new_outpoints.is_empty() {
1986 let (mut new_outpoints, new_outputs) = self.check_spend_holder_transaction(&tx, height, &logger);
1987 if !new_outputs.1.is_empty() {
1988 watch_outputs.push(new_outputs);
1990 claimable_outpoints.append(&mut new_outpoints);
1992 claimable_outpoints.append(&mut new_outpoints);
1995 if let Some(&commitment_number) = self.counterparty_commitment_txn_on_chain.get(&prevout.txid) {
1996 let (mut new_outpoints, new_outputs_option) = self.check_spend_counterparty_htlc(&tx, commitment_number, height, &logger);
1997 claimable_outpoints.append(&mut new_outpoints);
1998 if let Some(new_outputs) = new_outputs_option {
1999 watch_outputs.push(new_outputs);
2004 // While all commitment/HTLC-Success/HTLC-Timeout transactions have one input, HTLCs
2005 // can also be resolved in a few other ways which can have more than one output. Thus,
2006 // we call is_resolving_htlc_output here outside of the tx.input.len() == 1 check.
2007 self.is_resolving_htlc_output(&tx, height, &logger);
2009 self.is_paying_spendable_output(&tx, height, &logger);
2012 self.block_confirmed(height, txn_matched, watch_outputs, claimable_outpoints, broadcaster, fee_estimator, logger)
2015 fn block_confirmed<B: Deref, F: Deref, L: Deref>(
2018 txn_matched: Vec<&Transaction>,
2019 mut watch_outputs: Vec<TransactionOutputs>,
2020 mut claimable_outpoints: Vec<PackageTemplate>,
2024 ) -> Vec<TransactionOutputs>
2026 B::Target: BroadcasterInterface,
2027 F::Target: FeeEstimator,
2030 let should_broadcast = self.would_broadcast_at_height(height, &logger);
2031 if should_broadcast {
2032 let funding_outp = HolderFundingOutput::build(self.funding_redeemscript.clone());
2033 let commitment_package = PackageTemplate::build_package(self.funding_info.0.txid.clone(), self.funding_info.0.index as u32, PackageSolvingData::HolderFundingOutput(funding_outp), height, false, height);
2034 claimable_outpoints.push(commitment_package);
2035 self.pending_monitor_events.push(MonitorEvent::CommitmentTxBroadcasted(self.funding_info.0));
2036 let commitment_tx = self.onchain_tx_handler.get_fully_signed_holder_tx(&self.funding_redeemscript);
2037 self.holder_tx_signed = true;
2038 let (mut new_outpoints, _) = self.get_broadcasted_holder_claims(&self.current_holder_commitment_tx, height);
2039 let new_outputs = self.get_broadcasted_holder_watch_outputs(&self.current_holder_commitment_tx, &commitment_tx);
2040 if !new_outputs.is_empty() {
2041 watch_outputs.push((self.current_holder_commitment_tx.txid.clone(), new_outputs));
2043 claimable_outpoints.append(&mut new_outpoints);
2046 // Find which on-chain events have reached their confirmation threshold.
2047 let onchain_events_awaiting_threshold_conf =
2048 self.onchain_events_awaiting_threshold_conf.drain(..).collect::<Vec<_>>();
2049 let mut onchain_events_reaching_threshold_conf = Vec::new();
2050 for entry in onchain_events_awaiting_threshold_conf {
2051 if entry.has_reached_confirmation_threshold(height) {
2052 onchain_events_reaching_threshold_conf.push(entry);
2054 self.onchain_events_awaiting_threshold_conf.push(entry);
2058 // Used to check for duplicate HTLC resolutions.
2059 #[cfg(debug_assertions)]
2060 let unmatured_htlcs: Vec<_> = self.onchain_events_awaiting_threshold_conf
2062 .filter_map(|entry| match &entry.event {
2063 OnchainEvent::HTLCUpdate { source, .. } => Some(source),
2064 OnchainEvent::MaturingOutput { .. } => None,
2067 #[cfg(debug_assertions)]
2068 let mut matured_htlcs = Vec::new();
2070 // Produce actionable events from on-chain events having reached their threshold.
2071 for entry in onchain_events_reaching_threshold_conf.drain(..) {
2073 OnchainEvent::HTLCUpdate { ref source, payment_hash } => {
2074 // Check for duplicate HTLC resolutions.
2075 #[cfg(debug_assertions)]
2078 unmatured_htlcs.iter().find(|&htlc| htlc == &source).is_none(),
2079 "An unmature HTLC transaction conflicts with a maturing one; failed to \
2080 call either transaction_unconfirmed for the conflicting transaction \
2081 or block_disconnected for a block containing it.");
2083 matured_htlcs.iter().find(|&htlc| htlc == source).is_none(),
2084 "A matured HTLC transaction conflicts with a maturing one; failed to \
2085 call either transaction_unconfirmed for the conflicting transaction \
2086 or block_disconnected for a block containing it.");
2087 matured_htlcs.push(source.clone());
2090 log_trace!(logger, "HTLC {} failure update has got enough confirmations to be passed upstream", log_bytes!(payment_hash.0));
2091 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
2092 payment_hash: payment_hash,
2093 payment_preimage: None,
2094 source: source.clone(),
2097 OnchainEvent::MaturingOutput { descriptor } => {
2098 log_trace!(logger, "Descriptor {} has got enough confirmations to be passed upstream", log_spendable!(descriptor));
2099 self.pending_events.push(Event::SpendableOutputs {
2100 outputs: vec![descriptor]
2106 self.onchain_tx_handler.update_claims_view(&txn_matched, claimable_outpoints, height, &&*broadcaster, &&*fee_estimator, &&*logger);
2108 // Determine new outputs to watch by comparing against previously known outputs to watch,
2109 // updating the latter in the process.
2110 watch_outputs.retain(|&(ref txid, ref txouts)| {
2111 let idx_and_scripts = txouts.iter().map(|o| (o.0, o.1.script_pubkey.clone())).collect();
2112 self.outputs_to_watch.insert(txid.clone(), idx_and_scripts).is_none()
2116 // If we see a transaction for which we registered outputs previously,
2117 // make sure the registered scriptpubkey at the expected index match
2118 // the actual transaction output one. We failed this case before #653.
2119 for tx in &txn_matched {
2120 if let Some(outputs) = self.get_outputs_to_watch().get(&tx.txid()) {
2121 for idx_and_script in outputs.iter() {
2122 assert!((idx_and_script.0 as usize) < tx.output.len());
2123 assert_eq!(tx.output[idx_and_script.0 as usize].script_pubkey, idx_and_script.1);
2131 pub fn block_disconnected<B: Deref, F: Deref, L: Deref>(&mut self, header: &BlockHeader, height: u32, broadcaster: B, fee_estimator: F, logger: L)
2132 where B::Target: BroadcasterInterface,
2133 F::Target: FeeEstimator,
2136 log_trace!(logger, "Block {} at height {} disconnected", header.block_hash(), height);
2139 //- htlc update there as failure-trigger tx (revoked commitment tx, non-revoked commitment tx, HTLC-timeout tx) has been disconnected
2140 //- maturing spendable output has transaction paying us has been disconnected
2141 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| entry.height < height);
2143 self.onchain_tx_handler.block_disconnected(height, broadcaster, fee_estimator, logger);
2145 self.best_block = BestBlock::new(header.prev_blockhash, height - 1);
2148 fn transaction_unconfirmed<B: Deref, F: Deref, L: Deref>(
2155 B::Target: BroadcasterInterface,
2156 F::Target: FeeEstimator,
2159 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| entry.txid != *txid);
2160 self.onchain_tx_handler.transaction_unconfirmed(txid, broadcaster, fee_estimator, logger);
2163 /// Filters a block's `txdata` for transactions spending watched outputs or for any child
2164 /// transactions thereof.
2165 fn filter_block<'a>(&self, txdata: &TransactionData<'a>) -> Vec<&'a Transaction> {
2166 let mut matched_txn = HashSet::new();
2167 txdata.iter().filter(|&&(_, tx)| {
2168 let mut matches = self.spends_watched_output(tx);
2169 for input in tx.input.iter() {
2170 if matches { break; }
2171 if matched_txn.contains(&input.previous_output.txid) {
2176 matched_txn.insert(tx.txid());
2179 }).map(|(_, tx)| *tx).collect()
2182 /// Checks if a given transaction spends any watched outputs.
2183 fn spends_watched_output(&self, tx: &Transaction) -> bool {
2184 for input in tx.input.iter() {
2185 if let Some(outputs) = self.get_outputs_to_watch().get(&input.previous_output.txid) {
2186 for (idx, _script_pubkey) in outputs.iter() {
2187 if *idx == input.previous_output.vout {
2190 // If the expected script is a known type, check that the witness
2191 // appears to be spending the correct type (ie that the match would
2192 // actually succeed in BIP 158/159-style filters).
2193 if _script_pubkey.is_v0_p2wsh() {
2194 assert_eq!(&bitcoin::Address::p2wsh(&Script::from(input.witness.last().unwrap().clone()), bitcoin::Network::Bitcoin).script_pubkey(), _script_pubkey);
2195 } else if _script_pubkey.is_v0_p2wpkh() {
2196 assert_eq!(&bitcoin::Address::p2wpkh(&bitcoin::PublicKey::from_slice(&input.witness.last().unwrap()).unwrap(), bitcoin::Network::Bitcoin).unwrap().script_pubkey(), _script_pubkey);
2197 } else { panic!(); }
2208 fn would_broadcast_at_height<L: Deref>(&self, height: u32, logger: &L) -> bool where L::Target: Logger {
2209 // We need to consider all HTLCs which are:
2210 // * in any unrevoked counterparty commitment transaction, as they could broadcast said
2211 // transactions and we'd end up in a race, or
2212 // * are in our latest holder commitment transaction, as this is the thing we will
2213 // broadcast if we go on-chain.
2214 // Note that we consider HTLCs which were below dust threshold here - while they don't
2215 // strictly imply that we need to fail the channel, we need to go ahead and fail them back
2216 // to the source, and if we don't fail the channel we will have to ensure that the next
2217 // updates that peer sends us are update_fails, failing the channel if not. It's probably
2218 // easier to just fail the channel as this case should be rare enough anyway.
2219 macro_rules! scan_commitment {
2220 ($htlcs: expr, $holder_tx: expr) => {
2221 for ref htlc in $htlcs {
2222 // For inbound HTLCs which we know the preimage for, we have to ensure we hit the
2223 // chain with enough room to claim the HTLC without our counterparty being able to
2224 // time out the HTLC first.
2225 // For outbound HTLCs which our counterparty hasn't failed/claimed, our primary
2226 // concern is being able to claim the corresponding inbound HTLC (on another
2227 // channel) before it expires. In fact, we don't even really care if our
2228 // counterparty here claims such an outbound HTLC after it expired as long as we
2229 // can still claim the corresponding HTLC. Thus, to avoid needlessly hitting the
2230 // chain when our counterparty is waiting for expiration to off-chain fail an HTLC
2231 // we give ourselves a few blocks of headroom after expiration before going
2232 // on-chain for an expired HTLC.
2233 // Note that, to avoid a potential attack whereby a node delays claiming an HTLC
2234 // from us until we've reached the point where we go on-chain with the
2235 // corresponding inbound HTLC, we must ensure that outbound HTLCs go on chain at
2236 // least CLTV_CLAIM_BUFFER blocks prior to the inbound HTLC.
2237 // aka outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS == height - CLTV_CLAIM_BUFFER
2238 // inbound_cltv == height + CLTV_CLAIM_BUFFER
2239 // outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS + CLTV_CLAIM_BUFFER <= inbound_cltv - CLTV_CLAIM_BUFFER
2240 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= inbound_cltv - outbound_cltv
2241 // CLTV_EXPIRY_DELTA <= inbound_cltv - outbound_cltv (by check in ChannelManager::decode_update_add_htlc_onion)
2242 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= CLTV_EXPIRY_DELTA
2243 // The final, above, condition is checked for statically in channelmanager
2244 // with CHECK_CLTV_EXPIRY_SANITY_2.
2245 let htlc_outbound = $holder_tx == htlc.offered;
2246 if ( htlc_outbound && htlc.cltv_expiry + LATENCY_GRACE_PERIOD_BLOCKS <= height) ||
2247 (!htlc_outbound && htlc.cltv_expiry <= height + CLTV_CLAIM_BUFFER && self.payment_preimages.contains_key(&htlc.payment_hash)) {
2248 log_info!(logger, "Force-closing channel due to {} HTLC timeout, HTLC expiry is {}", if htlc_outbound { "outbound" } else { "inbound "}, htlc.cltv_expiry);
2255 scan_commitment!(self.current_holder_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, _)| a), true);
2257 if let Some(ref txid) = self.current_counterparty_commitment_txid {
2258 if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(txid) {
2259 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
2262 if let Some(ref txid) = self.prev_counterparty_commitment_txid {
2263 if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(txid) {
2264 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
2271 /// Check if any transaction broadcasted is resolving HTLC output by a success or timeout on a holder
2272 /// or counterparty commitment tx, if so send back the source, preimage if found and payment_hash of resolved HTLC
2273 fn is_resolving_htlc_output<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) where L::Target: Logger {
2274 'outer_loop: for input in &tx.input {
2275 let mut payment_data = None;
2276 let revocation_sig_claim = (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC) && input.witness[1].len() == 33)
2277 || (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::AcceptedHTLC) && input.witness[1].len() == 33);
2278 let accepted_preimage_claim = input.witness.len() == 5 && HTLCType::scriptlen_to_htlctype(input.witness[4].len()) == Some(HTLCType::AcceptedHTLC);
2279 let offered_preimage_claim = input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC);
2281 macro_rules! log_claim {
2282 ($tx_info: expr, $holder_tx: expr, $htlc: expr, $source_avail: expr) => {
2283 // We found the output in question, but aren't failing it backwards
2284 // as we have no corresponding source and no valid counterparty commitment txid
2285 // to try a weak source binding with same-hash, same-value still-valid offered HTLC.
2286 // This implies either it is an inbound HTLC or an outbound HTLC on a revoked transaction.
2287 let outbound_htlc = $holder_tx == $htlc.offered;
2288 if ($holder_tx && revocation_sig_claim) ||
2289 (outbound_htlc && !$source_avail && (accepted_preimage_claim || offered_preimage_claim)) {
2290 log_error!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}!",
2291 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
2292 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
2293 if revocation_sig_claim { "revocation sig" } else { "preimage claim after we'd passed the HTLC resolution back" });
2295 log_info!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}",
2296 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
2297 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
2298 if revocation_sig_claim { "revocation sig" } else if accepted_preimage_claim || offered_preimage_claim { "preimage" } else { "timeout" });
2303 macro_rules! check_htlc_valid_counterparty {
2304 ($counterparty_txid: expr, $htlc_output: expr) => {
2305 if let Some(txid) = $counterparty_txid {
2306 for &(ref pending_htlc, ref pending_source) in self.counterparty_claimable_outpoints.get(&txid).unwrap() {
2307 if pending_htlc.payment_hash == $htlc_output.payment_hash && pending_htlc.amount_msat == $htlc_output.amount_msat {
2308 if let &Some(ref source) = pending_source {
2309 log_claim!("revoked counterparty commitment tx", false, pending_htlc, true);
2310 payment_data = Some(((**source).clone(), $htlc_output.payment_hash));
2319 macro_rules! scan_commitment {
2320 ($htlcs: expr, $tx_info: expr, $holder_tx: expr) => {
2321 for (ref htlc_output, source_option) in $htlcs {
2322 if Some(input.previous_output.vout) == htlc_output.transaction_output_index {
2323 if let Some(ref source) = source_option {
2324 log_claim!($tx_info, $holder_tx, htlc_output, true);
2325 // We have a resolution of an HTLC either from one of our latest
2326 // holder commitment transactions or an unrevoked counterparty commitment
2327 // transaction. This implies we either learned a preimage, the HTLC
2328 // has timed out, or we screwed up. In any case, we should now
2329 // resolve the source HTLC with the original sender.
2330 payment_data = Some(((*source).clone(), htlc_output.payment_hash));
2331 } else if !$holder_tx {
2332 check_htlc_valid_counterparty!(self.current_counterparty_commitment_txid, htlc_output);
2333 if payment_data.is_none() {
2334 check_htlc_valid_counterparty!(self.prev_counterparty_commitment_txid, htlc_output);
2337 if payment_data.is_none() {
2338 log_claim!($tx_info, $holder_tx, htlc_output, false);
2339 continue 'outer_loop;
2346 if input.previous_output.txid == self.current_holder_commitment_tx.txid {
2347 scan_commitment!(self.current_holder_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
2348 "our latest holder commitment tx", true);
2350 if let Some(ref prev_holder_signed_commitment_tx) = self.prev_holder_signed_commitment_tx {
2351 if input.previous_output.txid == prev_holder_signed_commitment_tx.txid {
2352 scan_commitment!(prev_holder_signed_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
2353 "our previous holder commitment tx", true);
2356 if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(&input.previous_output.txid) {
2357 scan_commitment!(htlc_outputs.iter().map(|&(ref a, ref b)| (a, (b.as_ref().clone()).map(|boxed| &**boxed))),
2358 "counterparty commitment tx", false);
2361 // Check that scan_commitment, above, decided there is some source worth relaying an
2362 // HTLC resolution backwards to and figure out whether we learned a preimage from it.
2363 if let Some((source, payment_hash)) = payment_data {
2364 let mut payment_preimage = PaymentPreimage([0; 32]);
2365 if accepted_preimage_claim {
2366 if !self.pending_monitor_events.iter().any(
2367 |update| if let &MonitorEvent::HTLCEvent(ref upd) = update { upd.source == source } else { false }) {
2368 payment_preimage.0.copy_from_slice(&input.witness[3]);
2369 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
2371 payment_preimage: Some(payment_preimage),
2375 } else if offered_preimage_claim {
2376 if !self.pending_monitor_events.iter().any(
2377 |update| if let &MonitorEvent::HTLCEvent(ref upd) = update {
2378 upd.source == source
2380 payment_preimage.0.copy_from_slice(&input.witness[1]);
2381 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
2383 payment_preimage: Some(payment_preimage),
2388 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| {
2389 if entry.height != height { return true; }
2391 OnchainEvent::HTLCUpdate { source: ref htlc_source, .. } => {
2392 *htlc_source != source
2397 let entry = OnchainEventEntry {
2400 event: OnchainEvent::HTLCUpdate { source: source, payment_hash: payment_hash },
2402 log_info!(logger, "Failing HTLC with payment_hash {} timeout by a spend tx, waiting for confirmation (at height{})", log_bytes!(payment_hash.0), entry.confirmation_threshold());
2403 self.onchain_events_awaiting_threshold_conf.push(entry);
2409 /// Check if any transaction broadcasted is paying fund back to some address we can assume to own
2410 fn is_paying_spendable_output<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) where L::Target: Logger {
2411 let mut spendable_output = None;
2412 for (i, outp) in tx.output.iter().enumerate() { // There is max one spendable output for any channel tx, including ones generated by us
2413 if i > ::core::u16::MAX as usize {
2414 // While it is possible that an output exists on chain which is greater than the
2415 // 2^16th output in a given transaction, this is only possible if the output is not
2416 // in a lightning transaction and was instead placed there by some third party who
2417 // wishes to give us money for no reason.
2418 // Namely, any lightning transactions which we pre-sign will never have anywhere
2419 // near 2^16 outputs both because such transactions must have ~2^16 outputs who's
2420 // scripts are not longer than one byte in length and because they are inherently
2421 // non-standard due to their size.
2422 // Thus, it is completely safe to ignore such outputs, and while it may result in
2423 // us ignoring non-lightning fund to us, that is only possible if someone fills
2424 // nearly a full block with garbage just to hit this case.
2427 if outp.script_pubkey == self.destination_script {
2428 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
2429 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
2430 output: outp.clone(),
2433 } else if let Some(ref broadcasted_holder_revokable_script) = self.broadcasted_holder_revokable_script {
2434 if broadcasted_holder_revokable_script.0 == outp.script_pubkey {
2435 spendable_output = Some(SpendableOutputDescriptor::DelayedPaymentOutput(DelayedPaymentOutputDescriptor {
2436 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
2437 per_commitment_point: broadcasted_holder_revokable_script.1,
2438 to_self_delay: self.on_holder_tx_csv,
2439 output: outp.clone(),
2440 revocation_pubkey: broadcasted_holder_revokable_script.2.clone(),
2441 channel_keys_id: self.channel_keys_id,
2442 channel_value_satoshis: self.channel_value_satoshis,
2446 } else if self.counterparty_payment_script == outp.script_pubkey {
2447 spendable_output = Some(SpendableOutputDescriptor::StaticPaymentOutput(StaticPaymentOutputDescriptor {
2448 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
2449 output: outp.clone(),
2450 channel_keys_id: self.channel_keys_id,
2451 channel_value_satoshis: self.channel_value_satoshis,
2454 } else if outp.script_pubkey == self.shutdown_script {
2455 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
2456 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
2457 output: outp.clone(),
2461 if let Some(spendable_output) = spendable_output {
2462 let entry = OnchainEventEntry {
2465 event: OnchainEvent::MaturingOutput { descriptor: spendable_output.clone() },
2467 log_trace!(logger, "Maturing {} until {}", log_spendable!(spendable_output), entry.confirmation_threshold());
2468 self.onchain_events_awaiting_threshold_conf.push(entry);
2473 /// `Persist` defines behavior for persisting channel monitors: this could mean
2474 /// writing once to disk, and/or uploading to one or more backup services.
2476 /// Note that for every new monitor, you **must** persist the new `ChannelMonitor`
2477 /// to disk/backups. And, on every update, you **must** persist either the
2478 /// `ChannelMonitorUpdate` or the updated monitor itself. Otherwise, there is risk
2479 /// of situations such as revoking a transaction, then crashing before this
2480 /// revocation can be persisted, then unintentionally broadcasting a revoked
2481 /// transaction and losing money. This is a risk because previous channel states
2482 /// are toxic, so it's important that whatever channel state is persisted is
2483 /// kept up-to-date.
2484 pub trait Persist<ChannelSigner: Sign> {
2485 /// Persist a new channel's data. The data can be stored any way you want, but
2486 /// the identifier provided by Rust-Lightning is the channel's outpoint (and
2487 /// it is up to you to maintain a correct mapping between the outpoint and the
2488 /// stored channel data). Note that you **must** persist every new monitor to
2489 /// disk. See the `Persist` trait documentation for more details.
2491 /// See [`ChannelMonitor::write`] for writing out a `ChannelMonitor`,
2492 /// and [`ChannelMonitorUpdateErr`] for requirements when returning errors.
2493 fn persist_new_channel(&self, id: OutPoint, data: &ChannelMonitor<ChannelSigner>) -> Result<(), ChannelMonitorUpdateErr>;
2495 /// Update one channel's data. The provided `ChannelMonitor` has already
2496 /// applied the given update.
2498 /// Note that on every update, you **must** persist either the
2499 /// `ChannelMonitorUpdate` or the updated monitor itself to disk/backups. See
2500 /// the `Persist` trait documentation for more details.
2502 /// If an implementer chooses to persist the updates only, they need to make
2503 /// sure that all the updates are applied to the `ChannelMonitors` *before*
2504 /// the set of channel monitors is given to the `ChannelManager`
2505 /// deserialization routine. See [`ChannelMonitor::update_monitor`] for
2506 /// applying a monitor update to a monitor. If full `ChannelMonitors` are
2507 /// persisted, then there is no need to persist individual updates.
2509 /// Note that there could be a performance tradeoff between persisting complete
2510 /// channel monitors on every update vs. persisting only updates and applying
2511 /// them in batches. The size of each monitor grows `O(number of state updates)`
2512 /// whereas updates are small and `O(1)`.
2514 /// See [`ChannelMonitor::write`] for writing out a `ChannelMonitor`,
2515 /// [`ChannelMonitorUpdate::write`] for writing out an update, and
2516 /// [`ChannelMonitorUpdateErr`] for requirements when returning errors.
2517 fn update_persisted_channel(&self, id: OutPoint, update: &ChannelMonitorUpdate, data: &ChannelMonitor<ChannelSigner>) -> Result<(), ChannelMonitorUpdateErr>;
2520 impl<Signer: Sign, T: Deref, F: Deref, L: Deref> chain::Listen for (ChannelMonitor<Signer>, T, F, L)
2522 T::Target: BroadcasterInterface,
2523 F::Target: FeeEstimator,
2526 fn block_connected(&self, block: &Block, height: u32) {
2527 let txdata: Vec<_> = block.txdata.iter().enumerate().collect();
2528 self.0.block_connected(&block.header, &txdata, height, &*self.1, &*self.2, &*self.3);
2531 fn block_disconnected(&self, header: &BlockHeader, height: u32) {
2532 self.0.block_disconnected(header, height, &*self.1, &*self.2, &*self.3);
2536 impl<Signer: Sign, T: Deref, F: Deref, L: Deref> chain::Confirm for (ChannelMonitor<Signer>, T, F, L)
2538 T::Target: BroadcasterInterface,
2539 F::Target: FeeEstimator,
2542 fn transactions_confirmed(&self, header: &BlockHeader, txdata: &TransactionData, height: u32) {
2543 self.0.transactions_confirmed(header, txdata, height, &*self.1, &*self.2, &*self.3);
2546 fn transaction_unconfirmed(&self, txid: &Txid) {
2547 self.0.transaction_unconfirmed(txid, &*self.1, &*self.2, &*self.3);
2550 fn best_block_updated(&self, header: &BlockHeader, height: u32) {
2551 self.0.best_block_updated(header, height, &*self.1, &*self.2, &*self.3);
2554 fn get_relevant_txids(&self) -> Vec<Txid> {
2555 self.0.get_relevant_txids()
2559 const MAX_ALLOC_SIZE: usize = 64*1024;
2561 impl<'a, Signer: Sign, K: KeysInterface<Signer = Signer>> ReadableArgs<&'a K>
2562 for (BlockHash, ChannelMonitor<Signer>) {
2563 fn read<R: ::std::io::Read>(reader: &mut R, keys_manager: &'a K) -> Result<Self, DecodeError> {
2564 macro_rules! unwrap_obj {
2568 Err(_) => return Err(DecodeError::InvalidValue),
2573 let _ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
2575 let latest_update_id: u64 = Readable::read(reader)?;
2576 let commitment_transaction_number_obscure_factor = <U48 as Readable>::read(reader)?.0;
2578 let destination_script = Readable::read(reader)?;
2579 let broadcasted_holder_revokable_script = match <u8 as Readable>::read(reader)? {
2581 let revokable_address = Readable::read(reader)?;
2582 let per_commitment_point = Readable::read(reader)?;
2583 let revokable_script = Readable::read(reader)?;
2584 Some((revokable_address, per_commitment_point, revokable_script))
2587 _ => return Err(DecodeError::InvalidValue),
2589 let counterparty_payment_script = Readable::read(reader)?;
2590 let shutdown_script = Readable::read(reader)?;
2592 let channel_keys_id = Readable::read(reader)?;
2593 let holder_revocation_basepoint = Readable::read(reader)?;
2594 // Technically this can fail and serialize fail a round-trip, but only for serialization of
2595 // barely-init'd ChannelMonitors that we can't do anything with.
2596 let outpoint = OutPoint {
2597 txid: Readable::read(reader)?,
2598 index: Readable::read(reader)?,
2600 let funding_info = (outpoint, Readable::read(reader)?);
2601 let current_counterparty_commitment_txid = Readable::read(reader)?;
2602 let prev_counterparty_commitment_txid = Readable::read(reader)?;
2604 let counterparty_tx_cache = Readable::read(reader)?;
2605 let funding_redeemscript = Readable::read(reader)?;
2606 let channel_value_satoshis = Readable::read(reader)?;
2608 let their_cur_revocation_points = {
2609 let first_idx = <U48 as Readable>::read(reader)?.0;
2613 let first_point = Readable::read(reader)?;
2614 let second_point_slice: [u8; 33] = Readable::read(reader)?;
2615 if second_point_slice[0..32] == [0; 32] && second_point_slice[32] == 0 {
2616 Some((first_idx, first_point, None))
2618 Some((first_idx, first_point, Some(unwrap_obj!(PublicKey::from_slice(&second_point_slice)))))
2623 let on_holder_tx_csv: u16 = Readable::read(reader)?;
2625 let commitment_secrets = Readable::read(reader)?;
2627 macro_rules! read_htlc_in_commitment {
2630 let offered: bool = Readable::read(reader)?;
2631 let amount_msat: u64 = Readable::read(reader)?;
2632 let cltv_expiry: u32 = Readable::read(reader)?;
2633 let payment_hash: PaymentHash = Readable::read(reader)?;
2634 let transaction_output_index: Option<u32> = Readable::read(reader)?;
2636 HTLCOutputInCommitment {
2637 offered, amount_msat, cltv_expiry, payment_hash, transaction_output_index
2643 let counterparty_claimable_outpoints_len: u64 = Readable::read(reader)?;
2644 let mut counterparty_claimable_outpoints = HashMap::with_capacity(cmp::min(counterparty_claimable_outpoints_len as usize, MAX_ALLOC_SIZE / 64));
2645 for _ in 0..counterparty_claimable_outpoints_len {
2646 let txid: Txid = Readable::read(reader)?;
2647 let htlcs_count: u64 = Readable::read(reader)?;
2648 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
2649 for _ in 0..htlcs_count {
2650 htlcs.push((read_htlc_in_commitment!(), <Option<HTLCSource> as Readable>::read(reader)?.map(|o: HTLCSource| Box::new(o))));
2652 if let Some(_) = counterparty_claimable_outpoints.insert(txid, htlcs) {
2653 return Err(DecodeError::InvalidValue);
2657 let counterparty_commitment_txn_on_chain_len: u64 = Readable::read(reader)?;
2658 let mut counterparty_commitment_txn_on_chain = HashMap::with_capacity(cmp::min(counterparty_commitment_txn_on_chain_len as usize, MAX_ALLOC_SIZE / 32));
2659 for _ in 0..counterparty_commitment_txn_on_chain_len {
2660 let txid: Txid = Readable::read(reader)?;
2661 let commitment_number = <U48 as Readable>::read(reader)?.0;
2662 if let Some(_) = counterparty_commitment_txn_on_chain.insert(txid, commitment_number) {
2663 return Err(DecodeError::InvalidValue);
2667 let counterparty_hash_commitment_number_len: u64 = Readable::read(reader)?;
2668 let mut counterparty_hash_commitment_number = HashMap::with_capacity(cmp::min(counterparty_hash_commitment_number_len as usize, MAX_ALLOC_SIZE / 32));
2669 for _ in 0..counterparty_hash_commitment_number_len {
2670 let payment_hash: PaymentHash = Readable::read(reader)?;
2671 let commitment_number = <U48 as Readable>::read(reader)?.0;
2672 if let Some(_) = counterparty_hash_commitment_number.insert(payment_hash, commitment_number) {
2673 return Err(DecodeError::InvalidValue);
2677 let prev_holder_signed_commitment_tx = match <u8 as Readable>::read(reader)? {
2680 Some(Readable::read(reader)?)
2682 _ => return Err(DecodeError::InvalidValue),
2684 let current_holder_commitment_tx = Readable::read(reader)?;
2686 let current_counterparty_commitment_number = <U48 as Readable>::read(reader)?.0;
2687 let current_holder_commitment_number = <U48 as Readable>::read(reader)?.0;
2689 let payment_preimages_len: u64 = Readable::read(reader)?;
2690 let mut payment_preimages = HashMap::with_capacity(cmp::min(payment_preimages_len as usize, MAX_ALLOC_SIZE / 32));
2691 for _ in 0..payment_preimages_len {
2692 let preimage: PaymentPreimage = Readable::read(reader)?;
2693 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
2694 if let Some(_) = payment_preimages.insert(hash, preimage) {
2695 return Err(DecodeError::InvalidValue);
2699 let pending_monitor_events_len: u64 = Readable::read(reader)?;
2700 let mut pending_monitor_events = Vec::with_capacity(cmp::min(pending_monitor_events_len as usize, MAX_ALLOC_SIZE / (32 + 8*3)));
2701 for _ in 0..pending_monitor_events_len {
2702 let ev = match <u8 as Readable>::read(reader)? {
2703 0 => MonitorEvent::HTLCEvent(Readable::read(reader)?),
2704 1 => MonitorEvent::CommitmentTxBroadcasted(funding_info.0),
2705 _ => return Err(DecodeError::InvalidValue)
2707 pending_monitor_events.push(ev);
2710 let pending_events_len: u64 = Readable::read(reader)?;
2711 let mut pending_events = Vec::with_capacity(cmp::min(pending_events_len as usize, MAX_ALLOC_SIZE / mem::size_of::<Event>()));
2712 for _ in 0..pending_events_len {
2713 if let Some(event) = MaybeReadable::read(reader)? {
2714 pending_events.push(event);
2718 let best_block = BestBlock::new(Readable::read(reader)?, Readable::read(reader)?);
2720 let waiting_threshold_conf_len: u64 = Readable::read(reader)?;
2721 let mut onchain_events_awaiting_threshold_conf = Vec::with_capacity(cmp::min(waiting_threshold_conf_len as usize, MAX_ALLOC_SIZE / 128));
2722 for _ in 0..waiting_threshold_conf_len {
2723 onchain_events_awaiting_threshold_conf.push(Readable::read(reader)?);
2726 let outputs_to_watch_len: u64 = Readable::read(reader)?;
2727 let mut outputs_to_watch = HashMap::with_capacity(cmp::min(outputs_to_watch_len as usize, MAX_ALLOC_SIZE / (mem::size_of::<Txid>() + mem::size_of::<u32>() + mem::size_of::<Vec<Script>>())));
2728 for _ in 0..outputs_to_watch_len {
2729 let txid = Readable::read(reader)?;
2730 let outputs_len: u64 = Readable::read(reader)?;
2731 let mut outputs = Vec::with_capacity(cmp::min(outputs_len as usize, MAX_ALLOC_SIZE / (mem::size_of::<u32>() + mem::size_of::<Script>())));
2732 for _ in 0..outputs_len {
2733 outputs.push((Readable::read(reader)?, Readable::read(reader)?));
2735 if let Some(_) = outputs_to_watch.insert(txid, outputs) {
2736 return Err(DecodeError::InvalidValue);
2739 let onchain_tx_handler = ReadableArgs::read(reader, keys_manager)?;
2741 let lockdown_from_offchain = Readable::read(reader)?;
2742 let holder_tx_signed = Readable::read(reader)?;
2744 read_tlv_fields!(reader, {}, {});
2746 let mut secp_ctx = Secp256k1::new();
2747 secp_ctx.seeded_randomize(&keys_manager.get_secure_random_bytes());
2749 Ok((best_block.block_hash(), ChannelMonitor {
2750 inner: Mutex::new(ChannelMonitorImpl {
2752 commitment_transaction_number_obscure_factor,
2755 broadcasted_holder_revokable_script,
2756 counterparty_payment_script,
2760 holder_revocation_basepoint,
2762 current_counterparty_commitment_txid,
2763 prev_counterparty_commitment_txid,
2765 counterparty_tx_cache,
2766 funding_redeemscript,
2767 channel_value_satoshis,
2768 their_cur_revocation_points,
2773 counterparty_claimable_outpoints,
2774 counterparty_commitment_txn_on_chain,
2775 counterparty_hash_commitment_number,
2777 prev_holder_signed_commitment_tx,
2778 current_holder_commitment_tx,
2779 current_counterparty_commitment_number,
2780 current_holder_commitment_number,
2783 pending_monitor_events,
2786 onchain_events_awaiting_threshold_conf,
2791 lockdown_from_offchain,
2804 use bitcoin::blockdata::script::{Script, Builder};
2805 use bitcoin::blockdata::opcodes;
2806 use bitcoin::blockdata::transaction::{Transaction, TxIn, TxOut, SigHashType};
2807 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
2808 use bitcoin::util::bip143;
2809 use bitcoin::hashes::Hash;
2810 use bitcoin::hashes::sha256::Hash as Sha256;
2811 use bitcoin::hashes::hex::FromHex;
2812 use bitcoin::hash_types::Txid;
2813 use bitcoin::network::constants::Network;
2815 use chain::channelmonitor::ChannelMonitor;
2816 use chain::package::{WEIGHT_OFFERED_HTLC, WEIGHT_RECEIVED_HTLC, WEIGHT_REVOKED_OFFERED_HTLC, WEIGHT_REVOKED_RECEIVED_HTLC, WEIGHT_REVOKED_OUTPUT};
2817 use chain::transaction::OutPoint;
2818 use ln::{PaymentPreimage, PaymentHash};
2819 use ln::channelmanager::BestBlock;
2821 use ln::chan_utils::{HTLCOutputInCommitment, ChannelPublicKeys, ChannelTransactionParameters, HolderCommitmentTransaction, CounterpartyChannelTransactionParameters};
2822 use util::test_utils::{TestLogger, TestBroadcaster, TestFeeEstimator};
2823 use bitcoin::secp256k1::key::{SecretKey,PublicKey};
2824 use bitcoin::secp256k1::Secp256k1;
2825 use std::sync::{Arc, Mutex};
2826 use chain::keysinterface::InMemorySigner;
2830 fn test_prune_preimages() {
2831 let secp_ctx = Secp256k1::new();
2832 let logger = Arc::new(TestLogger::new());
2833 let broadcaster = Arc::new(TestBroadcaster{txn_broadcasted: Mutex::new(Vec::new()), blocks: Arc::new(Mutex::new(Vec::new()))});
2834 let fee_estimator = Arc::new(TestFeeEstimator { sat_per_kw: 253 });
2836 let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
2837 let dummy_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
2839 let mut preimages = Vec::new();
2842 let preimage = PaymentPreimage([i; 32]);
2843 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
2844 preimages.push((preimage, hash));
2848 macro_rules! preimages_slice_to_htlc_outputs {
2849 ($preimages_slice: expr) => {
2851 let mut res = Vec::new();
2852 for (idx, preimage) in $preimages_slice.iter().enumerate() {
2853 res.push((HTLCOutputInCommitment {
2857 payment_hash: preimage.1.clone(),
2858 transaction_output_index: Some(idx as u32),
2865 macro_rules! preimages_to_holder_htlcs {
2866 ($preimages_slice: expr) => {
2868 let mut inp = preimages_slice_to_htlc_outputs!($preimages_slice);
2869 let res: Vec<_> = inp.drain(..).map(|e| { (e.0, None, e.1) }).collect();
2875 macro_rules! test_preimages_exist {
2876 ($preimages_slice: expr, $monitor: expr) => {
2877 for preimage in $preimages_slice {
2878 assert!($monitor.inner.lock().unwrap().payment_preimages.contains_key(&preimage.1));
2883 let keys = InMemorySigner::new(
2885 SecretKey::from_slice(&[41; 32]).unwrap(),
2886 SecretKey::from_slice(&[41; 32]).unwrap(),
2887 SecretKey::from_slice(&[41; 32]).unwrap(),
2888 SecretKey::from_slice(&[41; 32]).unwrap(),
2889 SecretKey::from_slice(&[41; 32]).unwrap(),
2895 let counterparty_pubkeys = ChannelPublicKeys {
2896 funding_pubkey: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[44; 32]).unwrap()),
2897 revocation_basepoint: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()),
2898 payment_point: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[46; 32]).unwrap()),
2899 delayed_payment_basepoint: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[47; 32]).unwrap()),
2900 htlc_basepoint: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[48; 32]).unwrap())
2902 let funding_outpoint = OutPoint { txid: Default::default(), index: u16::max_value() };
2903 let channel_parameters = ChannelTransactionParameters {
2904 holder_pubkeys: keys.holder_channel_pubkeys.clone(),
2905 holder_selected_contest_delay: 66,
2906 is_outbound_from_holder: true,
2907 counterparty_parameters: Some(CounterpartyChannelTransactionParameters {
2908 pubkeys: counterparty_pubkeys,
2909 selected_contest_delay: 67,
2911 funding_outpoint: Some(funding_outpoint),
2913 // Prune with one old state and a holder commitment tx holding a few overlaps with the
2915 let best_block = BestBlock::from_genesis(Network::Testnet);
2916 let monitor = ChannelMonitor::new(Secp256k1::new(), keys,
2917 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap()), 0, &Script::new(),
2918 (OutPoint { txid: Txid::from_slice(&[43; 32]).unwrap(), index: 0 }, Script::new()),
2919 &channel_parameters,
2920 Script::new(), 46, 0,
2921 HolderCommitmentTransaction::dummy(), best_block);
2923 monitor.provide_latest_holder_commitment_tx(HolderCommitmentTransaction::dummy(), preimages_to_holder_htlcs!(preimages[0..10])).unwrap();
2924 let dummy_txid = dummy_tx.txid();
2925 monitor.provide_latest_counterparty_commitment_tx(dummy_txid, preimages_slice_to_htlc_outputs!(preimages[5..15]), 281474976710655, dummy_key, &logger);
2926 monitor.provide_latest_counterparty_commitment_tx(dummy_txid, preimages_slice_to_htlc_outputs!(preimages[15..20]), 281474976710654, dummy_key, &logger);
2927 monitor.provide_latest_counterparty_commitment_tx(dummy_txid, preimages_slice_to_htlc_outputs!(preimages[17..20]), 281474976710653, dummy_key, &logger);
2928 monitor.provide_latest_counterparty_commitment_tx(dummy_txid, preimages_slice_to_htlc_outputs!(preimages[18..20]), 281474976710652, dummy_key, &logger);
2929 for &(ref preimage, ref hash) in preimages.iter() {
2930 monitor.provide_payment_preimage(hash, preimage, &broadcaster, &fee_estimator, &logger);
2933 // Now provide a secret, pruning preimages 10-15
2934 let mut secret = [0; 32];
2935 secret[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2936 monitor.provide_secret(281474976710655, secret.clone()).unwrap();
2937 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 15);
2938 test_preimages_exist!(&preimages[0..10], monitor);
2939 test_preimages_exist!(&preimages[15..20], monitor);
2941 // Now provide a further secret, pruning preimages 15-17
2942 secret[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2943 monitor.provide_secret(281474976710654, secret.clone()).unwrap();
2944 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 13);
2945 test_preimages_exist!(&preimages[0..10], monitor);
2946 test_preimages_exist!(&preimages[17..20], monitor);
2948 // Now update holder commitment tx info, pruning only element 18 as we still care about the
2949 // previous commitment tx's preimages too
2950 monitor.provide_latest_holder_commitment_tx(HolderCommitmentTransaction::dummy(), preimages_to_holder_htlcs!(preimages[0..5])).unwrap();
2951 secret[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2952 monitor.provide_secret(281474976710653, secret.clone()).unwrap();
2953 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 12);
2954 test_preimages_exist!(&preimages[0..10], monitor);
2955 test_preimages_exist!(&preimages[18..20], monitor);
2957 // But if we do it again, we'll prune 5-10
2958 monitor.provide_latest_holder_commitment_tx(HolderCommitmentTransaction::dummy(), preimages_to_holder_htlcs!(preimages[0..3])).unwrap();
2959 secret[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2960 monitor.provide_secret(281474976710652, secret.clone()).unwrap();
2961 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 5);
2962 test_preimages_exist!(&preimages[0..5], monitor);
2966 fn test_claim_txn_weight_computation() {
2967 // We test Claim txn weight, knowing that we want expected weigth and
2968 // not actual case to avoid sigs and time-lock delays hell variances.
2970 let secp_ctx = Secp256k1::new();
2971 let privkey = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
2972 let pubkey = PublicKey::from_secret_key(&secp_ctx, &privkey);
2973 let mut sum_actual_sigs = 0;
2975 macro_rules! sign_input {
2976 ($sighash_parts: expr, $idx: expr, $amount: expr, $weight: expr, $sum_actual_sigs: expr) => {
2977 let htlc = HTLCOutputInCommitment {
2978 offered: if *$weight == WEIGHT_REVOKED_OFFERED_HTLC || *$weight == WEIGHT_OFFERED_HTLC { true } else { false },
2980 cltv_expiry: 2 << 16,
2981 payment_hash: PaymentHash([1; 32]),
2982 transaction_output_index: Some($idx as u32),
2984 let redeem_script = if *$weight == WEIGHT_REVOKED_OUTPUT { chan_utils::get_revokeable_redeemscript(&pubkey, 256, &pubkey) } else { chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &pubkey, &pubkey, &pubkey) };
2985 let sighash = hash_to_message!(&$sighash_parts.signature_hash($idx, &redeem_script, $amount, SigHashType::All)[..]);
2986 let sig = secp_ctx.sign(&sighash, &privkey);
2987 $sighash_parts.access_witness($idx).push(sig.serialize_der().to_vec());
2988 $sighash_parts.access_witness($idx)[0].push(SigHashType::All as u8);
2989 sum_actual_sigs += $sighash_parts.access_witness($idx)[0].len();
2990 if *$weight == WEIGHT_REVOKED_OUTPUT {
2991 $sighash_parts.access_witness($idx).push(vec!(1));
2992 } else if *$weight == WEIGHT_REVOKED_OFFERED_HTLC || *$weight == WEIGHT_REVOKED_RECEIVED_HTLC {
2993 $sighash_parts.access_witness($idx).push(pubkey.clone().serialize().to_vec());
2994 } else if *$weight == WEIGHT_RECEIVED_HTLC {
2995 $sighash_parts.access_witness($idx).push(vec![0]);
2997 $sighash_parts.access_witness($idx).push(PaymentPreimage([1; 32]).0.to_vec());
2999 $sighash_parts.access_witness($idx).push(redeem_script.into_bytes());
3000 println!("witness[0] {}", $sighash_parts.access_witness($idx)[0].len());
3001 println!("witness[1] {}", $sighash_parts.access_witness($idx)[1].len());
3002 println!("witness[2] {}", $sighash_parts.access_witness($idx)[2].len());
3006 let script_pubkey = Builder::new().push_opcode(opcodes::all::OP_RETURN).into_script();
3007 let txid = Txid::from_hex("56944c5d3f98413ef45cf54545538103cc9f298e0575820ad3591376e2e0f65d").unwrap();
3009 // Justice tx with 1 to_holder, 2 revoked offered HTLCs, 1 revoked received HTLCs
3010 let mut claim_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
3012 claim_tx.input.push(TxIn {
3013 previous_output: BitcoinOutPoint {
3017 script_sig: Script::new(),
3018 sequence: 0xfffffffd,
3019 witness: Vec::new(),
3022 claim_tx.output.push(TxOut {
3023 script_pubkey: script_pubkey.clone(),
3026 let base_weight = claim_tx.get_weight();
3027 let inputs_weight = vec![WEIGHT_REVOKED_OUTPUT, WEIGHT_REVOKED_OFFERED_HTLC, WEIGHT_REVOKED_OFFERED_HTLC, WEIGHT_REVOKED_RECEIVED_HTLC];
3028 let mut inputs_total_weight = 2; // count segwit flags
3030 let mut sighash_parts = bip143::SigHashCache::new(&mut claim_tx);
3031 for (idx, inp) in inputs_weight.iter().enumerate() {
3032 sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs);
3033 inputs_total_weight += inp;
3036 assert_eq!(base_weight + inputs_total_weight as usize, claim_tx.get_weight() + /* max_length_sig */ (73 * inputs_weight.len() - sum_actual_sigs));
3038 // Claim tx with 1 offered HTLCs, 3 received HTLCs
3039 claim_tx.input.clear();
3040 sum_actual_sigs = 0;
3042 claim_tx.input.push(TxIn {
3043 previous_output: BitcoinOutPoint {
3047 script_sig: Script::new(),
3048 sequence: 0xfffffffd,
3049 witness: Vec::new(),
3052 let base_weight = claim_tx.get_weight();
3053 let inputs_weight = vec![WEIGHT_OFFERED_HTLC, WEIGHT_RECEIVED_HTLC, WEIGHT_RECEIVED_HTLC, WEIGHT_RECEIVED_HTLC];
3054 let mut inputs_total_weight = 2; // count segwit flags
3056 let mut sighash_parts = bip143::SigHashCache::new(&mut claim_tx);
3057 for (idx, inp) in inputs_weight.iter().enumerate() {
3058 sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs);
3059 inputs_total_weight += inp;
3062 assert_eq!(base_weight + inputs_total_weight as usize, claim_tx.get_weight() + /* max_length_sig */ (73 * inputs_weight.len() - sum_actual_sigs));
3064 // Justice tx with 1 revoked HTLC-Success tx output
3065 claim_tx.input.clear();
3066 sum_actual_sigs = 0;
3067 claim_tx.input.push(TxIn {
3068 previous_output: BitcoinOutPoint {
3072 script_sig: Script::new(),
3073 sequence: 0xfffffffd,
3074 witness: Vec::new(),
3076 let base_weight = claim_tx.get_weight();
3077 let inputs_weight = vec![WEIGHT_REVOKED_OUTPUT];
3078 let mut inputs_total_weight = 2; // count segwit flags
3080 let mut sighash_parts = bip143::SigHashCache::new(&mut claim_tx);
3081 for (idx, inp) in inputs_weight.iter().enumerate() {
3082 sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs);
3083 inputs_total_weight += inp;
3086 assert_eq!(base_weight + inputs_total_weight as usize, claim_tx.get_weight() + /* max_length_isg */ (73 * inputs_weight.len() - sum_actual_sigs));
3089 // Further testing is done in the ChannelManager integration tests.