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 latest ChannelMonitor must always be actively monitoring for chain updates (and no out-of-date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::HTLCSource;
42 use chain::{BestBlock, 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;
56 use io::{self, Error};
60 /// An update generated by the underlying Channel itself which contains some new information the
61 /// ChannelMonitor should be made aware of.
62 #[cfg_attr(any(test, feature = "fuzztarget", feature = "_test_utils"), derive(PartialEq))]
65 pub struct ChannelMonitorUpdate {
66 pub(crate) updates: Vec<ChannelMonitorUpdateStep>,
67 /// The sequence number of this update. Updates *must* be replayed in-order according to this
68 /// sequence number (and updates may panic if they are not). The update_id values are strictly
69 /// increasing and increase by one for each new update, with one exception specified below.
71 /// This sequence number is also used to track up to which points updates which returned
72 /// ChannelMonitorUpdateErr::TemporaryFailure have been applied to all copies of a given
73 /// ChannelMonitor when ChannelManager::channel_monitor_updated is called.
75 /// The only instance where update_id values are not strictly increasing is the case where we
76 /// allow post-force-close updates with a special update ID of [`CLOSED_CHANNEL_UPDATE_ID`]. See
77 /// its docs for more details.
82 /// (1) a channel has been force closed and
83 /// (2) we receive a preimage from a forward link that allows us to spend an HTLC output on
84 /// this channel's (the backward link's) broadcasted commitment transaction
85 /// then we allow the `ChannelManager` to send a `ChannelMonitorUpdate` with this update ID,
86 /// with the update providing said payment preimage. No other update types are allowed after
88 pub const CLOSED_CHANNEL_UPDATE_ID: u64 = core::u64::MAX;
90 impl Writeable for ChannelMonitorUpdate {
91 fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
92 write_ver_prefix!(w, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
93 self.update_id.write(w)?;
94 (self.updates.len() as u64).write(w)?;
95 for update_step in self.updates.iter() {
96 update_step.write(w)?;
98 write_tlv_fields!(w, {});
102 impl Readable for ChannelMonitorUpdate {
103 fn read<R: io::Read>(r: &mut R) -> Result<Self, DecodeError> {
104 let _ver = read_ver_prefix!(r, SERIALIZATION_VERSION);
105 let update_id: u64 = Readable::read(r)?;
106 let len: u64 = Readable::read(r)?;
107 let mut updates = Vec::with_capacity(cmp::min(len as usize, MAX_ALLOC_SIZE / ::core::mem::size_of::<ChannelMonitorUpdateStep>()));
109 updates.push(Readable::read(r)?);
111 read_tlv_fields!(r, {});
112 Ok(Self { update_id, updates })
116 /// An error enum representing a failure to persist a channel monitor update.
117 #[derive(Clone, Copy, Debug, PartialEq)]
118 pub enum ChannelMonitorUpdateErr {
119 /// Used to indicate a temporary failure (eg connection to a watchtower or remote backup of
120 /// our state failed, but is expected to succeed at some point in the future).
122 /// Such a failure will "freeze" a channel, preventing us from revoking old states or
123 /// submitting new commitment transactions to the counterparty. Once the update(s) which failed
124 /// have been successfully applied, ChannelManager::channel_monitor_updated can be used to
125 /// restore the channel to an operational state.
127 /// Note that a given ChannelManager will *never* re-generate a given ChannelMonitorUpdate. If
128 /// you return a TemporaryFailure you must ensure that it is written to disk safely before
129 /// writing out the latest ChannelManager state.
131 /// Even when a channel has been "frozen" updates to the ChannelMonitor can continue to occur
132 /// (eg if an inbound HTLC which we forwarded was claimed upstream resulting in us attempting
133 /// to claim it on this channel) and those updates must be applied wherever they can be. At
134 /// least one such updated ChannelMonitor must be persisted otherwise PermanentFailure should
135 /// be returned to get things on-chain ASAP using only the in-memory copy. Obviously updates to
136 /// the channel which would invalidate previous ChannelMonitors are not made when a channel has
139 /// Note that even if updates made after TemporaryFailure succeed you must still call
140 /// channel_monitor_updated to ensure you have the latest monitor and re-enable normal channel
143 /// Note that the update being processed here will not be replayed for you when you call
144 /// ChannelManager::channel_monitor_updated, so you must store the update itself along
145 /// with the persisted ChannelMonitor on your own local disk prior to returning a
146 /// TemporaryFailure. You may, of course, employ a journaling approach, storing only the
147 /// ChannelMonitorUpdate on disk without updating the monitor itself, replaying the journal at
150 /// For deployments where a copy of ChannelMonitors and other local state are backed up in a
151 /// remote location (with local copies persisted immediately), it is anticipated that all
152 /// updates will return TemporaryFailure until the remote copies could be updated.
154 /// Used to indicate no further channel monitor updates will be allowed (eg we've moved on to a
155 /// different watchtower and cannot update with all watchtowers that were previously informed
156 /// of this channel).
158 /// At reception of this error, ChannelManager will force-close the channel and return at
159 /// least a final ChannelMonitorUpdate::ChannelForceClosed which must be delivered to at
160 /// least one ChannelMonitor copy. Revocation secret MUST NOT be released and offchain channel
161 /// update must be rejected.
163 /// This failure may also signal a failure to update the local persisted copy of one of
164 /// the channel monitor instance.
166 /// Note that even when you fail a holder commitment transaction update, you must store the
167 /// update to ensure you can claim from it in case of a duplicate copy of this ChannelMonitor
168 /// broadcasts it (e.g distributed channel-monitor deployment)
170 /// In case of distributed watchtowers deployment, the new version must be written to disk, as
171 /// state may have been stored but rejected due to a block forcing a commitment broadcast. This
172 /// storage is used to claim outputs of rejected state confirmed onchain by another watchtower,
173 /// lagging behind on block processing.
177 /// General Err type for ChannelMonitor actions. Generally, this implies that the data provided is
178 /// inconsistent with the ChannelMonitor being called. eg for ChannelMonitor::update_monitor this
179 /// means you tried to update a monitor for a different channel or the ChannelMonitorUpdate was
181 /// Contains a developer-readable error message.
182 #[derive(Clone, Debug)]
183 pub struct MonitorUpdateError(pub &'static str);
185 /// An event to be processed by the ChannelManager.
186 #[derive(Clone, PartialEq)]
187 pub enum MonitorEvent {
188 /// A monitor event containing an HTLCUpdate.
189 HTLCEvent(HTLCUpdate),
191 /// A monitor event that the Channel's commitment transaction was broadcasted.
192 CommitmentTxBroadcasted(OutPoint),
195 /// Simple structure sent back by `chain::Watch` when an HTLC from a forward channel is detected on
196 /// chain. Used to update the corresponding HTLC in the backward channel. Failing to pass the
197 /// preimage claim backward will lead to loss of funds.
198 #[derive(Clone, PartialEq)]
199 pub struct HTLCUpdate {
200 pub(crate) payment_hash: PaymentHash,
201 pub(crate) payment_preimage: Option<PaymentPreimage>,
202 pub(crate) source: HTLCSource,
203 pub(crate) onchain_value_satoshis: Option<u64>,
205 impl_writeable_tlv_based!(HTLCUpdate, {
206 (0, payment_hash, required),
207 (1, onchain_value_satoshis, option),
208 (2, source, required),
209 (4, payment_preimage, option),
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, {
278 (2, revocation_key, required),
279 (4, a_htlc_key, required),
280 (6, b_htlc_key, required),
281 (8, delayed_payment_key, required),
282 (10, per_commitment_point, required),
283 (12, feerate_per_kw, required),
284 (14, htlc_outputs, vec_type)
287 /// We use this to track counterparty commitment transactions and htlcs outputs and
288 /// use it to generate any justice or 2nd-stage preimage/timeout transactions.
290 struct CounterpartyCommitmentTransaction {
291 counterparty_delayed_payment_base_key: PublicKey,
292 counterparty_htlc_base_key: PublicKey,
293 on_counterparty_tx_csv: u16,
294 per_htlc: HashMap<Txid, Vec<HTLCOutputInCommitment>>
297 impl Writeable for CounterpartyCommitmentTransaction {
298 fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
299 w.write_all(&byte_utils::be64_to_array(self.per_htlc.len() as u64))?;
300 for (ref txid, ref htlcs) in self.per_htlc.iter() {
301 w.write_all(&txid[..])?;
302 w.write_all(&byte_utils::be64_to_array(htlcs.len() as u64))?;
303 for &ref htlc in htlcs.iter() {
307 write_tlv_fields!(w, {
308 (0, self.counterparty_delayed_payment_base_key, required),
309 (2, self.counterparty_htlc_base_key, required),
310 (4, self.on_counterparty_tx_csv, required),
315 impl Readable for CounterpartyCommitmentTransaction {
316 fn read<R: io::Read>(r: &mut R) -> Result<Self, DecodeError> {
317 let counterparty_commitment_transaction = {
318 let per_htlc_len: u64 = Readable::read(r)?;
319 let mut per_htlc = HashMap::with_capacity(cmp::min(per_htlc_len as usize, MAX_ALLOC_SIZE / 64));
320 for _ in 0..per_htlc_len {
321 let txid: Txid = Readable::read(r)?;
322 let htlcs_count: u64 = Readable::read(r)?;
323 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
324 for _ in 0..htlcs_count {
325 let htlc = Readable::read(r)?;
328 if let Some(_) = per_htlc.insert(txid, htlcs) {
329 return Err(DecodeError::InvalidValue);
332 let mut counterparty_delayed_payment_base_key = OptionDeserWrapper(None);
333 let mut counterparty_htlc_base_key = OptionDeserWrapper(None);
334 let mut on_counterparty_tx_csv: u16 = 0;
335 read_tlv_fields!(r, {
336 (0, counterparty_delayed_payment_base_key, required),
337 (2, counterparty_htlc_base_key, required),
338 (4, on_counterparty_tx_csv, required),
340 CounterpartyCommitmentTransaction {
341 counterparty_delayed_payment_base_key: counterparty_delayed_payment_base_key.0.unwrap(),
342 counterparty_htlc_base_key: counterparty_htlc_base_key.0.unwrap(),
343 on_counterparty_tx_csv,
347 Ok(counterparty_commitment_transaction)
351 /// An entry for an [`OnchainEvent`], stating the block height when the event was observed and the
352 /// transaction causing it.
354 /// Used to determine when the on-chain event can be considered safe from a chain reorganization.
356 struct OnchainEventEntry {
362 impl OnchainEventEntry {
363 fn confirmation_threshold(&self) -> u32 {
364 let mut conf_threshold = self.height + ANTI_REORG_DELAY - 1;
365 if let OnchainEvent::MaturingOutput {
366 descriptor: SpendableOutputDescriptor::DelayedPaymentOutput(ref descriptor)
368 // A CSV'd transaction is confirmable in block (input height) + CSV delay, which means
369 // it's broadcastable when we see the previous block.
370 conf_threshold = cmp::max(conf_threshold, self.height + descriptor.to_self_delay as u32 - 1);
375 fn has_reached_confirmation_threshold(&self, best_block: &BestBlock) -> bool {
376 best_block.height() >= self.confirmation_threshold()
380 /// Upon discovering of some classes of onchain tx by ChannelMonitor, we may have to take actions on it
381 /// once they mature to enough confirmations (ANTI_REORG_DELAY)
384 /// HTLC output getting solved by a timeout, at maturation we pass upstream payment source information to solve
385 /// inbound HTLC in backward channel. Note, in case of preimage, we pass info to upstream without delay as we can
386 /// only win from it, so it's never an OnchainEvent
389 payment_hash: PaymentHash,
390 onchain_value_satoshis: Option<u64>,
393 descriptor: SpendableOutputDescriptor,
397 impl_writeable_tlv_based!(OnchainEventEntry, {
399 (2, height, required),
400 (4, event, required),
403 impl_writeable_tlv_based_enum!(OnchainEvent,
405 (0, source, required),
406 (1, onchain_value_satoshis, option),
407 (2, payment_hash, required),
409 (1, MaturingOutput) => {
410 (0, descriptor, required),
414 #[cfg_attr(any(test, feature = "fuzztarget", feature = "_test_utils"), derive(PartialEq))]
416 pub(crate) enum ChannelMonitorUpdateStep {
417 LatestHolderCommitmentTXInfo {
418 commitment_tx: HolderCommitmentTransaction,
419 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
421 LatestCounterpartyCommitmentTXInfo {
422 commitment_txid: Txid,
423 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
424 commitment_number: u64,
425 their_revocation_point: PublicKey,
428 payment_preimage: PaymentPreimage,
434 /// Used to indicate that the no future updates will occur, and likely that the latest holder
435 /// commitment transaction(s) should be broadcast, as the channel has been force-closed.
437 /// If set to false, we shouldn't broadcast the latest holder commitment transaction as we
438 /// think we've fallen behind!
439 should_broadcast: bool,
443 impl_writeable_tlv_based_enum!(ChannelMonitorUpdateStep,
444 (0, LatestHolderCommitmentTXInfo) => {
445 (0, commitment_tx, required),
446 (2, htlc_outputs, vec_type),
448 (1, LatestCounterpartyCommitmentTXInfo) => {
449 (0, commitment_txid, required),
450 (2, commitment_number, required),
451 (4, their_revocation_point, required),
452 (6, htlc_outputs, vec_type),
454 (2, PaymentPreimage) => {
455 (0, payment_preimage, required),
457 (3, CommitmentSecret) => {
459 (2, secret, required),
461 (4, ChannelForceClosed) => {
462 (0, should_broadcast, required),
466 /// A ChannelMonitor handles chain events (blocks connected and disconnected) and generates
467 /// on-chain transactions to ensure no loss of funds occurs.
469 /// You MUST ensure that no ChannelMonitors for a given channel anywhere contain out-of-date
470 /// information and are actively monitoring the chain.
472 /// Pending Events or updated HTLCs which have not yet been read out by
473 /// get_and_clear_pending_monitor_events or get_and_clear_pending_events are serialized to disk and
474 /// reloaded at deserialize-time. Thus, you must ensure that, when handling events, all events
475 /// gotten are fully handled before re-serializing the new state.
477 /// Note that the deserializer is only implemented for (BlockHash, ChannelMonitor), which
478 /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
479 /// the "reorg path" (ie disconnecting blocks until you find a common ancestor from both the
480 /// returned block hash and the the current chain and then reconnecting blocks to get to the
481 /// best chain) upon deserializing the object!
482 pub struct ChannelMonitor<Signer: Sign> {
484 pub(crate) inner: Mutex<ChannelMonitorImpl<Signer>>,
486 inner: Mutex<ChannelMonitorImpl<Signer>>,
489 pub(crate) struct ChannelMonitorImpl<Signer: Sign> {
490 latest_update_id: u64,
491 commitment_transaction_number_obscure_factor: u64,
493 destination_script: Script,
494 broadcasted_holder_revokable_script: Option<(Script, PublicKey, PublicKey)>,
495 counterparty_payment_script: Script,
496 shutdown_script: Script,
498 channel_keys_id: [u8; 32],
499 holder_revocation_basepoint: PublicKey,
500 funding_info: (OutPoint, Script),
501 current_counterparty_commitment_txid: Option<Txid>,
502 prev_counterparty_commitment_txid: Option<Txid>,
504 counterparty_tx_cache: CounterpartyCommitmentTransaction,
505 funding_redeemscript: Script,
506 channel_value_satoshis: u64,
507 // first is the idx of the first of the two revocation points
508 their_cur_revocation_points: Option<(u64, PublicKey, Option<PublicKey>)>,
510 on_holder_tx_csv: u16,
512 commitment_secrets: CounterpartyCommitmentSecrets,
513 /// The set of outpoints in each counterparty commitment transaction. We always need at least
514 /// the payment hash from `HTLCOutputInCommitment` to claim even a revoked commitment
515 /// transaction broadcast as we need to be able to construct the witness script in all cases.
516 counterparty_claimable_outpoints: HashMap<Txid, Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>>,
517 /// We cannot identify HTLC-Success or HTLC-Timeout transactions by themselves on the chain.
518 /// Nor can we figure out their commitment numbers without the commitment transaction they are
519 /// spending. Thus, in order to claim them via revocation key, we track all the counterparty
520 /// commitment transactions which we find on-chain, mapping them to the commitment number which
521 /// can be used to derive the revocation key and claim the transactions.
522 counterparty_commitment_txn_on_chain: HashMap<Txid, u64>,
523 /// Cache used to make pruning of payment_preimages faster.
524 /// Maps payment_hash values to commitment numbers for counterparty transactions for non-revoked
525 /// counterparty transactions (ie should remain pretty small).
526 /// Serialized to disk but should generally not be sent to Watchtowers.
527 counterparty_hash_commitment_number: HashMap<PaymentHash, u64>,
529 // We store two holder commitment transactions to avoid any race conditions where we may update
530 // some monitors (potentially on watchtowers) but then fail to update others, resulting in the
531 // various monitors for one channel being out of sync, and us broadcasting a holder
532 // transaction for which we have deleted claim information on some watchtowers.
533 prev_holder_signed_commitment_tx: Option<HolderSignedTx>,
534 current_holder_commitment_tx: HolderSignedTx,
536 // Used just for ChannelManager to make sure it has the latest channel data during
538 current_counterparty_commitment_number: u64,
539 // Used just for ChannelManager to make sure it has the latest channel data during
541 current_holder_commitment_number: u64,
543 payment_preimages: HashMap<PaymentHash, PaymentPreimage>,
545 pending_monitor_events: Vec<MonitorEvent>,
546 pending_events: Vec<Event>,
548 // Used to track on-chain events (i.e., transactions part of channels confirmed on chain) on
549 // which to take actions once they reach enough confirmations. Each entry includes the
550 // transaction's id and the height when the transaction was confirmed on chain.
551 onchain_events_awaiting_threshold_conf: Vec<OnchainEventEntry>,
553 // If we get serialized out and re-read, we need to make sure that the chain monitoring
554 // interface knows about the TXOs that we want to be notified of spends of. We could probably
555 // be smart and derive them from the above storage fields, but its much simpler and more
556 // Obviously Correct (tm) if we just keep track of them explicitly.
557 outputs_to_watch: HashMap<Txid, Vec<(u32, Script)>>,
560 pub onchain_tx_handler: OnchainTxHandler<Signer>,
562 onchain_tx_handler: OnchainTxHandler<Signer>,
564 // This is set when the Channel[Manager] generated a ChannelMonitorUpdate which indicated the
565 // channel has been force-closed. After this is set, no further holder commitment transaction
566 // updates may occur, and we panic!() if one is provided.
567 lockdown_from_offchain: bool,
569 // Set once we've signed a holder commitment transaction and handed it over to our
570 // OnchainTxHandler. After this is set, no future updates to our holder commitment transactions
571 // may occur, and we fail any such monitor updates.
573 // In case of update rejection due to a locally already signed commitment transaction, we
574 // nevertheless store update content to track in case of concurrent broadcast by another
575 // remote monitor out-of-order with regards to the block view.
576 holder_tx_signed: bool,
578 // We simply modify best_block in Channel's block_connected so that serialization is
579 // consistent but hopefully the users' copy handles block_connected in a consistent way.
580 // (we do *not*, however, update them in update_monitor to ensure any local user copies keep
581 // their best_block from its state and not based on updated copies that didn't run through
582 // the full block_connected).
583 best_block: BestBlock,
585 secp_ctx: Secp256k1<secp256k1::All>, //TODO: dedup this a bit...
588 /// Transaction outputs to watch for on-chain spends.
589 pub type TransactionOutputs = (Txid, Vec<(u32, TxOut)>);
591 #[cfg(any(test, feature = "fuzztarget", feature = "_test_utils"))]
592 /// Used only in testing and fuzztarget to check serialization roundtrips don't change the
593 /// underlying object
594 impl<Signer: Sign> PartialEq for ChannelMonitor<Signer> {
595 fn eq(&self, other: &Self) -> bool {
596 let inner = self.inner.lock().unwrap();
597 let other = other.inner.lock().unwrap();
602 #[cfg(any(test, feature = "fuzztarget", feature = "_test_utils"))]
603 /// Used only in testing and fuzztarget to check serialization roundtrips don't change the
604 /// underlying object
605 impl<Signer: Sign> PartialEq for ChannelMonitorImpl<Signer> {
606 fn eq(&self, other: &Self) -> bool {
607 if self.latest_update_id != other.latest_update_id ||
608 self.commitment_transaction_number_obscure_factor != other.commitment_transaction_number_obscure_factor ||
609 self.destination_script != other.destination_script ||
610 self.broadcasted_holder_revokable_script != other.broadcasted_holder_revokable_script ||
611 self.counterparty_payment_script != other.counterparty_payment_script ||
612 self.channel_keys_id != other.channel_keys_id ||
613 self.holder_revocation_basepoint != other.holder_revocation_basepoint ||
614 self.funding_info != other.funding_info ||
615 self.current_counterparty_commitment_txid != other.current_counterparty_commitment_txid ||
616 self.prev_counterparty_commitment_txid != other.prev_counterparty_commitment_txid ||
617 self.counterparty_tx_cache != other.counterparty_tx_cache ||
618 self.funding_redeemscript != other.funding_redeemscript ||
619 self.channel_value_satoshis != other.channel_value_satoshis ||
620 self.their_cur_revocation_points != other.their_cur_revocation_points ||
621 self.on_holder_tx_csv != other.on_holder_tx_csv ||
622 self.commitment_secrets != other.commitment_secrets ||
623 self.counterparty_claimable_outpoints != other.counterparty_claimable_outpoints ||
624 self.counterparty_commitment_txn_on_chain != other.counterparty_commitment_txn_on_chain ||
625 self.counterparty_hash_commitment_number != other.counterparty_hash_commitment_number ||
626 self.prev_holder_signed_commitment_tx != other.prev_holder_signed_commitment_tx ||
627 self.current_counterparty_commitment_number != other.current_counterparty_commitment_number ||
628 self.current_holder_commitment_number != other.current_holder_commitment_number ||
629 self.current_holder_commitment_tx != other.current_holder_commitment_tx ||
630 self.payment_preimages != other.payment_preimages ||
631 self.pending_monitor_events != other.pending_monitor_events ||
632 self.pending_events.len() != other.pending_events.len() || // We trust events to round-trip properly
633 self.onchain_events_awaiting_threshold_conf != other.onchain_events_awaiting_threshold_conf ||
634 self.outputs_to_watch != other.outputs_to_watch ||
635 self.lockdown_from_offchain != other.lockdown_from_offchain ||
636 self.holder_tx_signed != other.holder_tx_signed
645 impl<Signer: Sign> Writeable for ChannelMonitor<Signer> {
646 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), Error> {
647 self.inner.lock().unwrap().write(writer)
651 // These are also used for ChannelMonitorUpdate, above.
652 const SERIALIZATION_VERSION: u8 = 1;
653 const MIN_SERIALIZATION_VERSION: u8 = 1;
655 impl<Signer: Sign> Writeable for ChannelMonitorImpl<Signer> {
656 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), Error> {
657 write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
659 self.latest_update_id.write(writer)?;
661 // Set in initial Channel-object creation, so should always be set by now:
662 U48(self.commitment_transaction_number_obscure_factor).write(writer)?;
664 self.destination_script.write(writer)?;
665 if let Some(ref broadcasted_holder_revokable_script) = self.broadcasted_holder_revokable_script {
666 writer.write_all(&[0; 1])?;
667 broadcasted_holder_revokable_script.0.write(writer)?;
668 broadcasted_holder_revokable_script.1.write(writer)?;
669 broadcasted_holder_revokable_script.2.write(writer)?;
671 writer.write_all(&[1; 1])?;
674 self.counterparty_payment_script.write(writer)?;
675 self.shutdown_script.write(writer)?;
677 self.channel_keys_id.write(writer)?;
678 self.holder_revocation_basepoint.write(writer)?;
679 writer.write_all(&self.funding_info.0.txid[..])?;
680 writer.write_all(&byte_utils::be16_to_array(self.funding_info.0.index))?;
681 self.funding_info.1.write(writer)?;
682 self.current_counterparty_commitment_txid.write(writer)?;
683 self.prev_counterparty_commitment_txid.write(writer)?;
685 self.counterparty_tx_cache.write(writer)?;
686 self.funding_redeemscript.write(writer)?;
687 self.channel_value_satoshis.write(writer)?;
689 match self.their_cur_revocation_points {
690 Some((idx, pubkey, second_option)) => {
691 writer.write_all(&byte_utils::be48_to_array(idx))?;
692 writer.write_all(&pubkey.serialize())?;
693 match second_option {
694 Some(second_pubkey) => {
695 writer.write_all(&second_pubkey.serialize())?;
698 writer.write_all(&[0; 33])?;
703 writer.write_all(&byte_utils::be48_to_array(0))?;
707 writer.write_all(&byte_utils::be16_to_array(self.on_holder_tx_csv))?;
709 self.commitment_secrets.write(writer)?;
711 macro_rules! serialize_htlc_in_commitment {
712 ($htlc_output: expr) => {
713 writer.write_all(&[$htlc_output.offered as u8; 1])?;
714 writer.write_all(&byte_utils::be64_to_array($htlc_output.amount_msat))?;
715 writer.write_all(&byte_utils::be32_to_array($htlc_output.cltv_expiry))?;
716 writer.write_all(&$htlc_output.payment_hash.0[..])?;
717 $htlc_output.transaction_output_index.write(writer)?;
721 writer.write_all(&byte_utils::be64_to_array(self.counterparty_claimable_outpoints.len() as u64))?;
722 for (ref txid, ref htlc_infos) in self.counterparty_claimable_outpoints.iter() {
723 writer.write_all(&txid[..])?;
724 writer.write_all(&byte_utils::be64_to_array(htlc_infos.len() as u64))?;
725 for &(ref htlc_output, ref htlc_source) in htlc_infos.iter() {
726 serialize_htlc_in_commitment!(htlc_output);
727 htlc_source.as_ref().map(|b| b.as_ref()).write(writer)?;
731 writer.write_all(&byte_utils::be64_to_array(self.counterparty_commitment_txn_on_chain.len() as u64))?;
732 for (ref txid, commitment_number) in self.counterparty_commitment_txn_on_chain.iter() {
733 writer.write_all(&txid[..])?;
734 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
737 writer.write_all(&byte_utils::be64_to_array(self.counterparty_hash_commitment_number.len() as u64))?;
738 for (ref payment_hash, commitment_number) in self.counterparty_hash_commitment_number.iter() {
739 writer.write_all(&payment_hash.0[..])?;
740 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
743 if let Some(ref prev_holder_tx) = self.prev_holder_signed_commitment_tx {
744 writer.write_all(&[1; 1])?;
745 prev_holder_tx.write(writer)?;
747 writer.write_all(&[0; 1])?;
750 self.current_holder_commitment_tx.write(writer)?;
752 writer.write_all(&byte_utils::be48_to_array(self.current_counterparty_commitment_number))?;
753 writer.write_all(&byte_utils::be48_to_array(self.current_holder_commitment_number))?;
755 writer.write_all(&byte_utils::be64_to_array(self.payment_preimages.len() as u64))?;
756 for payment_preimage in self.payment_preimages.values() {
757 writer.write_all(&payment_preimage.0[..])?;
760 writer.write_all(&byte_utils::be64_to_array(self.pending_monitor_events.len() as u64))?;
761 for event in self.pending_monitor_events.iter() {
763 MonitorEvent::HTLCEvent(upd) => {
767 MonitorEvent::CommitmentTxBroadcasted(_) => 1u8.write(writer)?
771 writer.write_all(&byte_utils::be64_to_array(self.pending_events.len() as u64))?;
772 for event in self.pending_events.iter() {
773 event.write(writer)?;
776 self.best_block.block_hash().write(writer)?;
777 writer.write_all(&byte_utils::be32_to_array(self.best_block.height()))?;
779 writer.write_all(&byte_utils::be64_to_array(self.onchain_events_awaiting_threshold_conf.len() as u64))?;
780 for ref entry in self.onchain_events_awaiting_threshold_conf.iter() {
781 entry.write(writer)?;
784 (self.outputs_to_watch.len() as u64).write(writer)?;
785 for (txid, idx_scripts) in self.outputs_to_watch.iter() {
787 (idx_scripts.len() as u64).write(writer)?;
788 for (idx, script) in idx_scripts.iter() {
790 script.write(writer)?;
793 self.onchain_tx_handler.write(writer)?;
795 self.lockdown_from_offchain.write(writer)?;
796 self.holder_tx_signed.write(writer)?;
798 write_tlv_fields!(writer, {});
804 impl<Signer: Sign> ChannelMonitor<Signer> {
805 pub(crate) fn new(secp_ctx: Secp256k1<secp256k1::All>, keys: Signer, shutdown_pubkey: &PublicKey,
806 on_counterparty_tx_csv: u16, destination_script: &Script, funding_info: (OutPoint, Script),
807 channel_parameters: &ChannelTransactionParameters,
808 funding_redeemscript: Script, channel_value_satoshis: u64,
809 commitment_transaction_number_obscure_factor: u64,
810 initial_holder_commitment_tx: HolderCommitmentTransaction,
811 best_block: BestBlock) -> ChannelMonitor<Signer> {
813 assert!(commitment_transaction_number_obscure_factor <= (1 << 48));
814 let our_channel_close_key_hash = WPubkeyHash::hash(&shutdown_pubkey.serialize());
815 let shutdown_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&our_channel_close_key_hash[..]).into_script();
816 let payment_key_hash = WPubkeyHash::hash(&keys.pubkeys().payment_point.serialize());
817 let counterparty_payment_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&payment_key_hash[..]).into_script();
819 let counterparty_channel_parameters = channel_parameters.counterparty_parameters.as_ref().unwrap();
820 let counterparty_delayed_payment_base_key = counterparty_channel_parameters.pubkeys.delayed_payment_basepoint;
821 let counterparty_htlc_base_key = counterparty_channel_parameters.pubkeys.htlc_basepoint;
822 let counterparty_tx_cache = CounterpartyCommitmentTransaction { counterparty_delayed_payment_base_key, counterparty_htlc_base_key, on_counterparty_tx_csv, per_htlc: HashMap::new() };
824 let channel_keys_id = keys.channel_keys_id();
825 let holder_revocation_basepoint = keys.pubkeys().revocation_basepoint;
827 // block for Rust 1.34 compat
828 let (holder_commitment_tx, current_holder_commitment_number) = {
829 let trusted_tx = initial_holder_commitment_tx.trust();
830 let txid = trusted_tx.txid();
832 let tx_keys = trusted_tx.keys();
833 let holder_commitment_tx = HolderSignedTx {
835 revocation_key: tx_keys.revocation_key,
836 a_htlc_key: tx_keys.broadcaster_htlc_key,
837 b_htlc_key: tx_keys.countersignatory_htlc_key,
838 delayed_payment_key: tx_keys.broadcaster_delayed_payment_key,
839 per_commitment_point: tx_keys.per_commitment_point,
840 feerate_per_kw: trusted_tx.feerate_per_kw(),
841 htlc_outputs: Vec::new(), // There are never any HTLCs in the initial commitment transactions
843 (holder_commitment_tx, trusted_tx.commitment_number())
846 let onchain_tx_handler =
847 OnchainTxHandler::new(destination_script.clone(), keys,
848 channel_parameters.clone(), initial_holder_commitment_tx, secp_ctx.clone());
850 let mut outputs_to_watch = HashMap::new();
851 outputs_to_watch.insert(funding_info.0.txid, vec![(funding_info.0.index as u32, funding_info.1.clone())]);
854 inner: Mutex::new(ChannelMonitorImpl {
856 commitment_transaction_number_obscure_factor,
858 destination_script: destination_script.clone(),
859 broadcasted_holder_revokable_script: None,
860 counterparty_payment_script,
864 holder_revocation_basepoint,
866 current_counterparty_commitment_txid: None,
867 prev_counterparty_commitment_txid: None,
869 counterparty_tx_cache,
870 funding_redeemscript,
871 channel_value_satoshis,
872 their_cur_revocation_points: None,
874 on_holder_tx_csv: counterparty_channel_parameters.selected_contest_delay,
876 commitment_secrets: CounterpartyCommitmentSecrets::new(),
877 counterparty_claimable_outpoints: HashMap::new(),
878 counterparty_commitment_txn_on_chain: HashMap::new(),
879 counterparty_hash_commitment_number: HashMap::new(),
881 prev_holder_signed_commitment_tx: None,
882 current_holder_commitment_tx: holder_commitment_tx,
883 current_counterparty_commitment_number: 1 << 48,
884 current_holder_commitment_number,
886 payment_preimages: HashMap::new(),
887 pending_monitor_events: Vec::new(),
888 pending_events: Vec::new(),
890 onchain_events_awaiting_threshold_conf: Vec::new(),
895 lockdown_from_offchain: false,
896 holder_tx_signed: false,
906 fn provide_secret(&self, idx: u64, secret: [u8; 32]) -> Result<(), MonitorUpdateError> {
907 self.inner.lock().unwrap().provide_secret(idx, secret)
910 /// Informs this monitor of the latest counterparty (ie non-broadcastable) commitment transaction.
911 /// The monitor watches for it to be broadcasted and then uses the HTLC information (and
912 /// possibly future revocation/preimage information) to claim outputs where possible.
913 /// We cache also the mapping hash:commitment number to lighten pruning of old preimages by watchtowers.
914 pub(crate) fn provide_latest_counterparty_commitment_tx<L: Deref>(
917 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
918 commitment_number: u64,
919 their_revocation_point: PublicKey,
921 ) where L::Target: Logger {
922 self.inner.lock().unwrap().provide_latest_counterparty_commitment_tx(
923 txid, htlc_outputs, commitment_number, their_revocation_point, logger)
927 fn provide_latest_holder_commitment_tx(
929 holder_commitment_tx: HolderCommitmentTransaction,
930 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
931 ) -> Result<(), MonitorUpdateError> {
932 self.inner.lock().unwrap().provide_latest_holder_commitment_tx(
933 holder_commitment_tx, htlc_outputs)
937 pub(crate) fn provide_payment_preimage<B: Deref, F: Deref, L: Deref>(
939 payment_hash: &PaymentHash,
940 payment_preimage: &PaymentPreimage,
945 B::Target: BroadcasterInterface,
946 F::Target: FeeEstimator,
949 self.inner.lock().unwrap().provide_payment_preimage(
950 payment_hash, payment_preimage, broadcaster, fee_estimator, logger)
953 pub(crate) fn broadcast_latest_holder_commitment_txn<B: Deref, L: Deref>(
958 B::Target: BroadcasterInterface,
961 self.inner.lock().unwrap().broadcast_latest_holder_commitment_txn(broadcaster, logger)
964 /// Updates a ChannelMonitor on the basis of some new information provided by the Channel
967 /// panics if the given update is not the next update by update_id.
968 pub fn update_monitor<B: Deref, F: Deref, L: Deref>(
970 updates: &ChannelMonitorUpdate,
974 ) -> Result<(), MonitorUpdateError>
976 B::Target: BroadcasterInterface,
977 F::Target: FeeEstimator,
980 self.inner.lock().unwrap().update_monitor(updates, broadcaster, fee_estimator, logger)
983 /// Gets the update_id from the latest ChannelMonitorUpdate which was applied to this
985 pub fn get_latest_update_id(&self) -> u64 {
986 self.inner.lock().unwrap().get_latest_update_id()
989 /// Gets the funding transaction outpoint of the channel this ChannelMonitor is monitoring for.
990 pub fn get_funding_txo(&self) -> (OutPoint, Script) {
991 self.inner.lock().unwrap().get_funding_txo().clone()
994 /// Gets a list of txids, with their output scripts (in the order they appear in the
995 /// transaction), which we must learn about spends of via block_connected().
996 pub fn get_outputs_to_watch(&self) -> Vec<(Txid, Vec<(u32, Script)>)> {
997 self.inner.lock().unwrap().get_outputs_to_watch()
998 .iter().map(|(txid, outputs)| (*txid, outputs.clone())).collect()
1001 /// Loads the funding txo and outputs to watch into the given `chain::Filter` by repeatedly
1002 /// calling `chain::Filter::register_output` and `chain::Filter::register_tx` until all outputs
1003 /// have been registered.
1004 pub fn load_outputs_to_watch<F: Deref>(&self, filter: &F) where F::Target: chain::Filter {
1005 let lock = self.inner.lock().unwrap();
1006 filter.register_tx(&lock.get_funding_txo().0.txid, &lock.get_funding_txo().1);
1007 for (txid, outputs) in lock.get_outputs_to_watch().iter() {
1008 for (index, script_pubkey) in outputs.iter() {
1009 assert!(*index <= u16::max_value() as u32);
1010 filter.register_output(WatchedOutput {
1012 outpoint: OutPoint { txid: *txid, index: *index as u16 },
1013 script_pubkey: script_pubkey.clone(),
1019 /// Get the list of HTLCs who's status has been updated on chain. This should be called by
1020 /// ChannelManager via [`chain::Watch::release_pending_monitor_events`].
1021 pub fn get_and_clear_pending_monitor_events(&self) -> Vec<MonitorEvent> {
1022 self.inner.lock().unwrap().get_and_clear_pending_monitor_events()
1025 /// Gets the list of pending events which were generated by previous actions, clearing the list
1028 /// This is called by ChainMonitor::get_and_clear_pending_events() and is equivalent to
1029 /// EventsProvider::get_and_clear_pending_events() except that it requires &mut self as we do
1030 /// no internal locking in ChannelMonitors.
1031 pub fn get_and_clear_pending_events(&self) -> Vec<Event> {
1032 self.inner.lock().unwrap().get_and_clear_pending_events()
1035 pub(crate) fn get_min_seen_secret(&self) -> u64 {
1036 self.inner.lock().unwrap().get_min_seen_secret()
1039 pub(crate) fn get_cur_counterparty_commitment_number(&self) -> u64 {
1040 self.inner.lock().unwrap().get_cur_counterparty_commitment_number()
1043 pub(crate) fn get_cur_holder_commitment_number(&self) -> u64 {
1044 self.inner.lock().unwrap().get_cur_holder_commitment_number()
1047 /// Used by ChannelManager deserialization to broadcast the latest holder state if its copy of
1048 /// the Channel was out-of-date. You may use it to get a broadcastable holder toxic tx in case of
1049 /// fallen-behind, i.e when receiving a channel_reestablish with a proof that our counterparty side knows
1050 /// a higher revocation secret than the holder commitment number we are aware of. Broadcasting these
1051 /// transactions are UNSAFE, as they allow counterparty side to punish you. Nevertheless you may want to
1052 /// broadcast them if counterparty don't close channel with his higher commitment transaction after a
1053 /// substantial amount of time (a month or even a year) to get back funds. Best may be to contact
1054 /// out-of-band the other node operator to coordinate with him if option is available to you.
1055 /// In any-case, choice is up to the user.
1056 pub fn get_latest_holder_commitment_txn<L: Deref>(&self, logger: &L) -> Vec<Transaction>
1057 where L::Target: Logger {
1058 self.inner.lock().unwrap().get_latest_holder_commitment_txn(logger)
1061 /// Unsafe test-only version of get_latest_holder_commitment_txn used by our test framework
1062 /// to bypass HolderCommitmentTransaction state update lockdown after signature and generate
1063 /// revoked commitment transaction.
1064 #[cfg(any(test, feature = "unsafe_revoked_tx_signing"))]
1065 pub fn unsafe_get_latest_holder_commitment_txn<L: Deref>(&self, logger: &L) -> Vec<Transaction>
1066 where L::Target: Logger {
1067 self.inner.lock().unwrap().unsafe_get_latest_holder_commitment_txn(logger)
1070 /// Processes transactions in a newly connected block, which may result in any of the following:
1071 /// - update the monitor's state against resolved HTLCs
1072 /// - punish the counterparty in the case of seeing a revoked commitment transaction
1073 /// - force close the channel and claim/timeout incoming/outgoing HTLCs if near expiration
1074 /// - detect settled outputs for later spending
1075 /// - schedule and bump any in-flight claims
1077 /// Returns any new outputs to watch from `txdata`; after called, these are also included in
1078 /// [`get_outputs_to_watch`].
1080 /// [`get_outputs_to_watch`]: #method.get_outputs_to_watch
1081 pub fn block_connected<B: Deref, F: Deref, L: Deref>(
1083 header: &BlockHeader,
1084 txdata: &TransactionData,
1089 ) -> Vec<TransactionOutputs>
1091 B::Target: BroadcasterInterface,
1092 F::Target: FeeEstimator,
1095 self.inner.lock().unwrap().block_connected(
1096 header, txdata, height, broadcaster, fee_estimator, logger)
1099 /// Determines if the disconnected block contained any transactions of interest and updates
1101 pub fn block_disconnected<B: Deref, F: Deref, L: Deref>(
1103 header: &BlockHeader,
1109 B::Target: BroadcasterInterface,
1110 F::Target: FeeEstimator,
1113 self.inner.lock().unwrap().block_disconnected(
1114 header, height, broadcaster, fee_estimator, logger)
1117 /// Processes transactions confirmed in a block with the given header and height, returning new
1118 /// outputs to watch. See [`block_connected`] for details.
1120 /// Used instead of [`block_connected`] by clients that are notified of transactions rather than
1121 /// blocks. See [`chain::Confirm`] for calling expectations.
1123 /// [`block_connected`]: Self::block_connected
1124 pub fn transactions_confirmed<B: Deref, F: Deref, L: Deref>(
1126 header: &BlockHeader,
1127 txdata: &TransactionData,
1132 ) -> Vec<TransactionOutputs>
1134 B::Target: BroadcasterInterface,
1135 F::Target: FeeEstimator,
1138 self.inner.lock().unwrap().transactions_confirmed(
1139 header, txdata, height, broadcaster, fee_estimator, logger)
1142 /// Processes a transaction that was reorganized out of the chain.
1144 /// Used instead of [`block_disconnected`] by clients that are notified of transactions rather
1145 /// than blocks. See [`chain::Confirm`] for calling expectations.
1147 /// [`block_disconnected`]: Self::block_disconnected
1148 pub fn transaction_unconfirmed<B: Deref, F: Deref, L: Deref>(
1155 B::Target: BroadcasterInterface,
1156 F::Target: FeeEstimator,
1159 self.inner.lock().unwrap().transaction_unconfirmed(
1160 txid, broadcaster, fee_estimator, logger);
1163 /// Updates the monitor with the current best chain tip, returning new outputs to watch. See
1164 /// [`block_connected`] for details.
1166 /// Used instead of [`block_connected`] by clients that are notified of transactions rather than
1167 /// blocks. See [`chain::Confirm`] for calling expectations.
1169 /// [`block_connected`]: Self::block_connected
1170 pub fn best_block_updated<B: Deref, F: Deref, L: Deref>(
1172 header: &BlockHeader,
1177 ) -> Vec<TransactionOutputs>
1179 B::Target: BroadcasterInterface,
1180 F::Target: FeeEstimator,
1183 self.inner.lock().unwrap().best_block_updated(
1184 header, height, broadcaster, fee_estimator, logger)
1187 /// Returns the set of txids that should be monitored for re-organization out of the chain.
1188 pub fn get_relevant_txids(&self) -> Vec<Txid> {
1189 let inner = self.inner.lock().unwrap();
1190 let mut txids: Vec<Txid> = inner.onchain_events_awaiting_threshold_conf
1192 .map(|entry| entry.txid)
1193 .chain(inner.onchain_tx_handler.get_relevant_txids().into_iter())
1195 txids.sort_unstable();
1200 /// Gets the latest best block which was connected either via the [`chain::Listen`] or
1201 /// [`chain::Confirm`] interfaces.
1202 pub fn current_best_block(&self) -> BestBlock {
1203 self.inner.lock().unwrap().best_block.clone()
1207 /// Compares a broadcasted commitment transaction's HTLCs with those in the latest state,
1208 /// failing any HTLCs which didn't make it into the broadcasted commitment transaction back
1209 /// after ANTI_REORG_DELAY blocks.
1211 /// We always compare against the set of HTLCs in counterparty commitment transactions, as those
1212 /// are the commitment transactions which are generated by us. The off-chain state machine in
1213 /// `Channel` will automatically resolve any HTLCs which were never included in a commitment
1214 /// transaction when it detects channel closure, but it is up to us to ensure any HTLCs which were
1215 /// included in a remote commitment transaction are failed back if they are not present in the
1216 /// broadcasted commitment transaction.
1218 /// Specifically, the removal process for HTLCs in `Channel` is always based on the counterparty
1219 /// sending a `revoke_and_ack`, which causes us to clear `prev_counterparty_commitment_txid`. Thus,
1220 /// as long as we examine both the current counterparty commitment transaction and, if it hasn't
1221 /// been revoked yet, the previous one, we we will never "forget" to resolve an HTLC.
1222 macro_rules! fail_unbroadcast_htlcs {
1223 ($self: expr, $commitment_tx_type: expr, $commitment_tx_conf_height: expr, $confirmed_htlcs_list: expr, $logger: expr) => { {
1224 macro_rules! check_htlc_fails {
1225 ($txid: expr, $commitment_tx: expr) => {
1226 if let Some(ref latest_outpoints) = $self.counterparty_claimable_outpoints.get($txid) {
1227 for &(ref htlc, ref source_option) in latest_outpoints.iter() {
1228 if let &Some(ref source) = source_option {
1229 // Check if the HTLC is present in the commitment transaction that was
1230 // broadcast, but not if it was below the dust limit, which we should
1231 // fail backwards immediately as there is no way for us to learn the
1232 // payment_preimage.
1233 // Note that if the dust limit were allowed to change between
1234 // commitment transactions we'd want to be check whether *any*
1235 // broadcastable commitment transaction has the HTLC in it, but it
1236 // cannot currently change after channel initialization, so we don't
1238 let confirmed_htlcs_iter: &mut Iterator<Item = (&HTLCOutputInCommitment, Option<&HTLCSource>)> = &mut $confirmed_htlcs_list;
1239 let mut matched_htlc = false;
1240 for (ref broadcast_htlc, ref broadcast_source) in confirmed_htlcs_iter {
1241 if broadcast_htlc.transaction_output_index.is_some() && Some(&**source) == *broadcast_source {
1242 matched_htlc = true;
1246 if matched_htlc { continue; }
1247 $self.onchain_events_awaiting_threshold_conf.retain(|ref entry| {
1248 if entry.height != $commitment_tx_conf_height { return true; }
1250 OnchainEvent::HTLCUpdate { source: ref update_source, .. } => {
1251 *update_source != **source
1256 let entry = OnchainEventEntry {
1258 height: $commitment_tx_conf_height,
1259 event: OnchainEvent::HTLCUpdate {
1260 source: (**source).clone(),
1261 payment_hash: htlc.payment_hash.clone(),
1262 onchain_value_satoshis: Some(htlc.amount_msat / 1000),
1265 log_trace!($logger, "Failing HTLC with payment_hash {} from {} counterparty commitment tx due to broadcast of {} commitment transaction, waiting for confirmation (at height {})",
1266 log_bytes!(htlc.payment_hash.0), $commitment_tx, $commitment_tx_type, entry.confirmation_threshold());
1267 $self.onchain_events_awaiting_threshold_conf.push(entry);
1273 if let Some(ref txid) = $self.current_counterparty_commitment_txid {
1274 check_htlc_fails!(txid, "current");
1276 if let Some(ref txid) = $self.prev_counterparty_commitment_txid {
1277 check_htlc_fails!(txid, "previous");
1282 impl<Signer: Sign> ChannelMonitorImpl<Signer> {
1283 /// Inserts a revocation secret into this channel monitor. Prunes old preimages if neither
1284 /// needed by holder commitment transactions HTCLs nor by counterparty ones. Unless we haven't already seen
1285 /// counterparty commitment transaction's secret, they are de facto pruned (we can use revocation key).
1286 fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), MonitorUpdateError> {
1287 if let Err(()) = self.commitment_secrets.provide_secret(idx, secret) {
1288 return Err(MonitorUpdateError("Previous secret did not match new one"));
1291 // Prune HTLCs from the previous counterparty commitment tx so we don't generate failure/fulfill
1292 // events for now-revoked/fulfilled HTLCs.
1293 if let Some(txid) = self.prev_counterparty_commitment_txid.take() {
1294 for &mut (_, ref mut source) in self.counterparty_claimable_outpoints.get_mut(&txid).unwrap() {
1299 if !self.payment_preimages.is_empty() {
1300 let cur_holder_signed_commitment_tx = &self.current_holder_commitment_tx;
1301 let prev_holder_signed_commitment_tx = self.prev_holder_signed_commitment_tx.as_ref();
1302 let min_idx = self.get_min_seen_secret();
1303 let counterparty_hash_commitment_number = &mut self.counterparty_hash_commitment_number;
1305 self.payment_preimages.retain(|&k, _| {
1306 for &(ref htlc, _, _) in cur_holder_signed_commitment_tx.htlc_outputs.iter() {
1307 if k == htlc.payment_hash {
1311 if let Some(prev_holder_commitment_tx) = prev_holder_signed_commitment_tx {
1312 for &(ref htlc, _, _) in prev_holder_commitment_tx.htlc_outputs.iter() {
1313 if k == htlc.payment_hash {
1318 let contains = if let Some(cn) = counterparty_hash_commitment_number.get(&k) {
1325 counterparty_hash_commitment_number.remove(&k);
1334 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 {
1335 // TODO: Encrypt the htlc_outputs data with the single-hash of the commitment transaction
1336 // so that a remote monitor doesn't learn anything unless there is a malicious close.
1337 // (only maybe, sadly we cant do the same for local info, as we need to be aware of
1339 for &(ref htlc, _) in &htlc_outputs {
1340 self.counterparty_hash_commitment_number.insert(htlc.payment_hash, commitment_number);
1343 log_trace!(logger, "Tracking new counterparty commitment transaction with txid {} at commitment number {} with {} HTLC outputs", txid, commitment_number, htlc_outputs.len());
1344 self.prev_counterparty_commitment_txid = self.current_counterparty_commitment_txid.take();
1345 self.current_counterparty_commitment_txid = Some(txid);
1346 self.counterparty_claimable_outpoints.insert(txid, htlc_outputs.clone());
1347 self.current_counterparty_commitment_number = commitment_number;
1348 //TODO: Merge this into the other per-counterparty-transaction output storage stuff
1349 match self.their_cur_revocation_points {
1350 Some(old_points) => {
1351 if old_points.0 == commitment_number + 1 {
1352 self.their_cur_revocation_points = Some((old_points.0, old_points.1, Some(their_revocation_point)));
1353 } else if old_points.0 == commitment_number + 2 {
1354 if let Some(old_second_point) = old_points.2 {
1355 self.their_cur_revocation_points = Some((old_points.0 - 1, old_second_point, Some(their_revocation_point)));
1357 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1360 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1364 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1367 let mut htlcs = Vec::with_capacity(htlc_outputs.len());
1368 for htlc in htlc_outputs {
1369 if htlc.0.transaction_output_index.is_some() {
1373 self.counterparty_tx_cache.per_htlc.insert(txid, htlcs);
1376 /// Informs this monitor of the latest holder (ie broadcastable) commitment transaction. The
1377 /// monitor watches for timeouts and may broadcast it if we approach such a timeout. Thus, it
1378 /// is important that any clones of this channel monitor (including remote clones) by kept
1379 /// up-to-date as our holder commitment transaction is updated.
1380 /// Panics if set_on_holder_tx_csv has never been called.
1381 fn provide_latest_holder_commitment_tx(&mut self, holder_commitment_tx: HolderCommitmentTransaction, htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>) -> Result<(), MonitorUpdateError> {
1382 // block for Rust 1.34 compat
1383 let mut new_holder_commitment_tx = {
1384 let trusted_tx = holder_commitment_tx.trust();
1385 let txid = trusted_tx.txid();
1386 let tx_keys = trusted_tx.keys();
1387 self.current_holder_commitment_number = trusted_tx.commitment_number();
1390 revocation_key: tx_keys.revocation_key,
1391 a_htlc_key: tx_keys.broadcaster_htlc_key,
1392 b_htlc_key: tx_keys.countersignatory_htlc_key,
1393 delayed_payment_key: tx_keys.broadcaster_delayed_payment_key,
1394 per_commitment_point: tx_keys.per_commitment_point,
1395 feerate_per_kw: trusted_tx.feerate_per_kw(),
1399 self.onchain_tx_handler.provide_latest_holder_tx(holder_commitment_tx);
1400 mem::swap(&mut new_holder_commitment_tx, &mut self.current_holder_commitment_tx);
1401 self.prev_holder_signed_commitment_tx = Some(new_holder_commitment_tx);
1402 if self.holder_tx_signed {
1403 return Err(MonitorUpdateError("Latest holder commitment signed has already been signed, update is rejected"));
1408 /// Provides a payment_hash->payment_preimage mapping. Will be automatically pruned when all
1409 /// commitment_tx_infos which contain the payment hash have been revoked.
1410 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)
1411 where B::Target: BroadcasterInterface,
1412 F::Target: FeeEstimator,
1415 self.payment_preimages.insert(payment_hash.clone(), payment_preimage.clone());
1417 // If the channel is force closed, try to claim the output from this preimage.
1418 // First check if a counterparty commitment transaction has been broadcasted:
1419 macro_rules! claim_htlcs {
1420 ($commitment_number: expr, $txid: expr) => {
1421 let htlc_claim_reqs = self.get_counterparty_htlc_output_claim_reqs($commitment_number, $txid, None);
1422 self.onchain_tx_handler.update_claims_view(&Vec::new(), htlc_claim_reqs, self.best_block.height(), self.best_block.height(), broadcaster, fee_estimator, logger);
1425 if let Some(txid) = self.current_counterparty_commitment_txid {
1426 if let Some(commitment_number) = self.counterparty_commitment_txn_on_chain.get(&txid) {
1427 claim_htlcs!(*commitment_number, txid);
1431 if let Some(txid) = self.prev_counterparty_commitment_txid {
1432 if let Some(commitment_number) = self.counterparty_commitment_txn_on_chain.get(&txid) {
1433 claim_htlcs!(*commitment_number, txid);
1438 // Then if a holder commitment transaction has been seen on-chain, broadcast transactions
1439 // claiming the HTLC output from each of the holder commitment transactions.
1440 // Note that we can't just use `self.holder_tx_signed`, because that only covers the case where
1441 // *we* sign a holder commitment transaction, not when e.g. a watchtower broadcasts one of our
1442 // holder commitment transactions.
1443 if self.broadcasted_holder_revokable_script.is_some() {
1444 // Assume that the broadcasted commitment transaction confirmed in the current best
1445 // block. Even if not, its a reasonable metric for the bump criteria on the HTLC
1447 let (claim_reqs, _) = self.get_broadcasted_holder_claims(&self.current_holder_commitment_tx, self.best_block.height());
1448 self.onchain_tx_handler.update_claims_view(&Vec::new(), claim_reqs, self.best_block.height(), self.best_block.height(), broadcaster, fee_estimator, logger);
1449 if let Some(ref tx) = self.prev_holder_signed_commitment_tx {
1450 let (claim_reqs, _) = self.get_broadcasted_holder_claims(&tx, self.best_block.height());
1451 self.onchain_tx_handler.update_claims_view(&Vec::new(), claim_reqs, self.best_block.height(), self.best_block.height(), broadcaster, fee_estimator, logger);
1456 pub(crate) fn broadcast_latest_holder_commitment_txn<B: Deref, L: Deref>(&mut self, broadcaster: &B, logger: &L)
1457 where B::Target: BroadcasterInterface,
1460 for tx in self.get_latest_holder_commitment_txn(logger).iter() {
1461 log_info!(logger, "Broadcasting local {}", log_tx!(tx));
1462 broadcaster.broadcast_transaction(tx);
1464 self.pending_monitor_events.push(MonitorEvent::CommitmentTxBroadcasted(self.funding_info.0));
1467 pub fn update_monitor<B: Deref, F: Deref, L: Deref>(&mut self, updates: &ChannelMonitorUpdate, broadcaster: &B, fee_estimator: &F, logger: &L) -> Result<(), MonitorUpdateError>
1468 where B::Target: BroadcasterInterface,
1469 F::Target: FeeEstimator,
1472 // ChannelMonitor updates may be applied after force close if we receive a
1473 // preimage for a broadcasted commitment transaction HTLC output that we'd
1474 // like to claim on-chain. If this is the case, we no longer have guaranteed
1475 // access to the monitor's update ID, so we use a sentinel value instead.
1476 if updates.update_id == CLOSED_CHANNEL_UPDATE_ID {
1477 match updates.updates[0] {
1478 ChannelMonitorUpdateStep::PaymentPreimage { .. } => {},
1479 _ => panic!("Attempted to apply post-force-close ChannelMonitorUpdate that wasn't providing a payment preimage"),
1481 assert_eq!(updates.updates.len(), 1);
1482 } else if self.latest_update_id + 1 != updates.update_id {
1483 panic!("Attempted to apply ChannelMonitorUpdates out of order, check the update_id before passing an update to update_monitor!");
1485 for update in updates.updates.iter() {
1487 ChannelMonitorUpdateStep::LatestHolderCommitmentTXInfo { commitment_tx, htlc_outputs } => {
1488 log_trace!(logger, "Updating ChannelMonitor with latest holder commitment transaction info");
1489 if self.lockdown_from_offchain { panic!(); }
1490 self.provide_latest_holder_commitment_tx(commitment_tx.clone(), htlc_outputs.clone())?
1492 ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo { commitment_txid, htlc_outputs, commitment_number, their_revocation_point } => {
1493 log_trace!(logger, "Updating ChannelMonitor with latest counterparty commitment transaction info");
1494 self.provide_latest_counterparty_commitment_tx(*commitment_txid, htlc_outputs.clone(), *commitment_number, *their_revocation_point, logger)
1496 ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage } => {
1497 log_trace!(logger, "Updating ChannelMonitor with payment preimage");
1498 self.provide_payment_preimage(&PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()), &payment_preimage, broadcaster, fee_estimator, logger)
1500 ChannelMonitorUpdateStep::CommitmentSecret { idx, secret } => {
1501 log_trace!(logger, "Updating ChannelMonitor with commitment secret");
1502 self.provide_secret(*idx, *secret)?
1504 ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast } => {
1505 log_trace!(logger, "Updating ChannelMonitor: channel force closed, should broadcast: {}", should_broadcast);
1506 self.lockdown_from_offchain = true;
1507 if *should_broadcast {
1508 self.broadcast_latest_holder_commitment_txn(broadcaster, logger);
1509 } else if !self.holder_tx_signed {
1510 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");
1512 // If we generated a MonitorEvent::CommitmentTxBroadcasted, the ChannelManager
1513 // will still give us a ChannelForceClosed event with !should_broadcast, but we
1514 // shouldn't print the scary warning above.
1515 log_info!(logger, "Channel off-chain state closed after we broadcasted our latest commitment transaction.");
1520 self.latest_update_id = updates.update_id;
1524 pub fn get_latest_update_id(&self) -> u64 {
1525 self.latest_update_id
1528 pub fn get_funding_txo(&self) -> &(OutPoint, Script) {
1532 pub fn get_outputs_to_watch(&self) -> &HashMap<Txid, Vec<(u32, Script)>> {
1533 // If we've detected a counterparty commitment tx on chain, we must include it in the set
1534 // of outputs to watch for spends of, otherwise we're likely to lose user funds. Because
1535 // its trivial to do, double-check that here.
1536 for (txid, _) in self.counterparty_commitment_txn_on_chain.iter() {
1537 self.outputs_to_watch.get(txid).expect("Counterparty commitment txn which have been broadcast should have outputs registered");
1539 &self.outputs_to_watch
1542 pub fn get_and_clear_pending_monitor_events(&mut self) -> Vec<MonitorEvent> {
1543 let mut ret = Vec::new();
1544 mem::swap(&mut ret, &mut self.pending_monitor_events);
1548 pub fn get_and_clear_pending_events(&mut self) -> Vec<Event> {
1549 let mut ret = Vec::new();
1550 mem::swap(&mut ret, &mut self.pending_events);
1554 /// Can only fail if idx is < get_min_seen_secret
1555 fn get_secret(&self, idx: u64) -> Option<[u8; 32]> {
1556 self.commitment_secrets.get_secret(idx)
1559 pub(crate) fn get_min_seen_secret(&self) -> u64 {
1560 self.commitment_secrets.get_min_seen_secret()
1563 pub(crate) fn get_cur_counterparty_commitment_number(&self) -> u64 {
1564 self.current_counterparty_commitment_number
1567 pub(crate) fn get_cur_holder_commitment_number(&self) -> u64 {
1568 self.current_holder_commitment_number
1571 /// Attempts to claim a counterparty commitment transaction's outputs using the revocation key and
1572 /// data in counterparty_claimable_outpoints. Will directly claim any HTLC outputs which expire at a
1573 /// height > height + CLTV_SHARED_CLAIM_BUFFER. In any case, will install monitoring for
1574 /// HTLC-Success/HTLC-Timeout transactions.
1575 /// Return updates for HTLC pending in the channel and failed automatically by the broadcast of
1576 /// revoked counterparty commitment tx
1577 fn check_spend_counterparty_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) -> (Vec<PackageTemplate>, TransactionOutputs) where L::Target: Logger {
1578 // Most secp and related errors trying to create keys means we have no hope of constructing
1579 // a spend transaction...so we return no transactions to broadcast
1580 let mut claimable_outpoints = Vec::new();
1581 let mut watch_outputs = Vec::new();
1583 let commitment_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
1584 let per_commitment_option = self.counterparty_claimable_outpoints.get(&commitment_txid);
1586 macro_rules! ignore_error {
1587 ( $thing : expr ) => {
1590 Err(_) => return (claimable_outpoints, (commitment_txid, watch_outputs))
1595 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);
1596 if commitment_number >= self.get_min_seen_secret() {
1597 let secret = self.get_secret(commitment_number).unwrap();
1598 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
1599 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1600 let revocation_pubkey = ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &self.holder_revocation_basepoint));
1601 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));
1603 let revokeable_redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.counterparty_tx_cache.on_counterparty_tx_csv, &delayed_key);
1604 let revokeable_p2wsh = revokeable_redeemscript.to_v0_p2wsh();
1606 // First, process non-htlc outputs (to_holder & to_counterparty)
1607 for (idx, outp) in tx.output.iter().enumerate() {
1608 if outp.script_pubkey == revokeable_p2wsh {
1609 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);
1610 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);
1611 claimable_outpoints.push(justice_package);
1615 // Then, try to find revoked htlc outputs
1616 if let Some(ref per_commitment_data) = per_commitment_option {
1617 for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
1618 if let Some(transaction_output_index) = htlc.transaction_output_index {
1619 if transaction_output_index as usize >= tx.output.len() ||
1620 tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
1621 return (claimable_outpoints, (commitment_txid, watch_outputs)); // Corrupted per_commitment_data, fuck this user
1623 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());
1624 let justice_package = PackageTemplate::build_package(commitment_txid, transaction_output_index, PackageSolvingData::RevokedHTLCOutput(revk_htlc_outp), htlc.cltv_expiry, true, height);
1625 claimable_outpoints.push(justice_package);
1630 // Last, track onchain revoked commitment transaction and fail backward outgoing HTLCs as payment path is broken
1631 if !claimable_outpoints.is_empty() || per_commitment_option.is_some() { // ie we're confident this is actually ours
1632 // We're definitely a counterparty commitment transaction!
1633 log_error!(logger, "Got broadcast of revoked counterparty commitment transaction, going to generate general spend tx with {} inputs", claimable_outpoints.len());
1634 for (idx, outp) in tx.output.iter().enumerate() {
1635 watch_outputs.push((idx as u32, outp.clone()));
1637 self.counterparty_commitment_txn_on_chain.insert(commitment_txid, commitment_number);
1639 fail_unbroadcast_htlcs!(self, "revoked counterparty", height, [].iter().map(|a| *a), logger);
1641 } else if let Some(per_commitment_data) = per_commitment_option {
1642 // While this isn't useful yet, there is a potential race where if a counterparty
1643 // revokes a state at the same time as the commitment transaction for that state is
1644 // confirmed, and the watchtower receives the block before the user, the user could
1645 // upload a new ChannelMonitor with the revocation secret but the watchtower has
1646 // already processed the block, resulting in the counterparty_commitment_txn_on_chain entry
1647 // not being generated by the above conditional. Thus, to be safe, we go ahead and
1649 for (idx, outp) in tx.output.iter().enumerate() {
1650 watch_outputs.push((idx as u32, outp.clone()));
1652 self.counterparty_commitment_txn_on_chain.insert(commitment_txid, commitment_number);
1654 log_info!(logger, "Got broadcast of non-revoked counterparty commitment transaction {}", commitment_txid);
1655 fail_unbroadcast_htlcs!(self, "counterparty", height, per_commitment_data.iter().map(|(a, b)| (a, b.as_ref().map(|b| b.as_ref()))), logger);
1657 let htlc_claim_reqs = self.get_counterparty_htlc_output_claim_reqs(commitment_number, commitment_txid, Some(tx));
1658 for req in htlc_claim_reqs {
1659 claimable_outpoints.push(req);
1663 (claimable_outpoints, (commitment_txid, watch_outputs))
1666 fn get_counterparty_htlc_output_claim_reqs(&self, commitment_number: u64, commitment_txid: Txid, tx: Option<&Transaction>) -> Vec<PackageTemplate> {
1667 let mut claimable_outpoints = Vec::new();
1668 if let Some(htlc_outputs) = self.counterparty_claimable_outpoints.get(&commitment_txid) {
1669 if let Some(revocation_points) = self.their_cur_revocation_points {
1670 let revocation_point_option =
1671 // If the counterparty commitment tx is the latest valid state, use their latest
1672 // per-commitment point
1673 if revocation_points.0 == commitment_number { Some(&revocation_points.1) }
1674 else if let Some(point) = revocation_points.2.as_ref() {
1675 // If counterparty commitment tx is the state previous to the latest valid state, use
1676 // their previous per-commitment point (non-atomicity of revocation means it's valid for
1677 // them to temporarily have two valid commitment txns from our viewpoint)
1678 if revocation_points.0 == commitment_number + 1 { Some(point) } else { None }
1680 if let Some(revocation_point) = revocation_point_option {
1681 for (_, &(ref htlc, _)) in htlc_outputs.iter().enumerate() {
1682 if let Some(transaction_output_index) = htlc.transaction_output_index {
1683 if let Some(transaction) = tx {
1684 if transaction_output_index as usize >= transaction.output.len() ||
1685 transaction.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
1686 return claimable_outpoints; // Corrupted per_commitment_data, fuck this user
1689 let preimage = if htlc.offered { if let Some(p) = self.payment_preimages.get(&htlc.payment_hash) { Some(*p) } else { None } } else { None };
1690 if preimage.is_some() || !htlc.offered {
1691 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())) };
1692 let aggregation = if !htlc.offered { false } else { true };
1693 let counterparty_package = PackageTemplate::build_package(commitment_txid, transaction_output_index, counterparty_htlc_outp, htlc.cltv_expiry,aggregation, 0);
1694 claimable_outpoints.push(counterparty_package);
1704 /// Attempts to claim a counterparty HTLC-Success/HTLC-Timeout's outputs using the revocation key
1705 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 {
1706 let htlc_txid = tx.txid();
1707 if tx.input.len() != 1 || tx.output.len() != 1 || tx.input[0].witness.len() != 5 {
1708 return (Vec::new(), None)
1711 macro_rules! ignore_error {
1712 ( $thing : expr ) => {
1715 Err(_) => return (Vec::new(), None)
1720 let secret = if let Some(secret) = self.get_secret(commitment_number) { secret } else { return (Vec::new(), None); };
1721 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
1722 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1724 log_error!(logger, "Got broadcast of revoked counterparty HTLC transaction, spending {}:{}", htlc_txid, 0);
1725 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);
1726 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);
1727 let claimable_outpoints = vec!(justice_package);
1728 let outputs = vec![(0, tx.output[0].clone())];
1729 (claimable_outpoints, Some((htlc_txid, outputs)))
1732 // Returns (1) `PackageTemplate`s that can be given to the OnChainTxHandler, so that the handler can
1733 // broadcast transactions claiming holder HTLC commitment outputs and (2) a holder revokable
1734 // script so we can detect whether a holder transaction has been seen on-chain.
1735 fn get_broadcasted_holder_claims(&self, holder_tx: &HolderSignedTx, conf_height: u32) -> (Vec<PackageTemplate>, Option<(Script, PublicKey, PublicKey)>) {
1736 let mut claim_requests = Vec::with_capacity(holder_tx.htlc_outputs.len());
1738 let redeemscript = chan_utils::get_revokeable_redeemscript(&holder_tx.revocation_key, self.on_holder_tx_csv, &holder_tx.delayed_payment_key);
1739 let broadcasted_holder_revokable_script = Some((redeemscript.to_v0_p2wsh(), holder_tx.per_commitment_point.clone(), holder_tx.revocation_key.clone()));
1741 for &(ref htlc, _, _) in holder_tx.htlc_outputs.iter() {
1742 if let Some(transaction_output_index) = htlc.transaction_output_index {
1743 let htlc_output = if htlc.offered {
1744 HolderHTLCOutput::build_offered(htlc.amount_msat, htlc.cltv_expiry)
1746 let payment_preimage = if let Some(preimage) = self.payment_preimages.get(&htlc.payment_hash) {
1749 // We can't build an HTLC-Success transaction without the preimage
1752 HolderHTLCOutput::build_accepted(payment_preimage, htlc.amount_msat)
1754 let htlc_package = PackageTemplate::build_package(holder_tx.txid, transaction_output_index, PackageSolvingData::HolderHTLCOutput(htlc_output), htlc.cltv_expiry, false, conf_height);
1755 claim_requests.push(htlc_package);
1759 (claim_requests, broadcasted_holder_revokable_script)
1762 // Returns holder HTLC outputs to watch and react to in case of spending.
1763 fn get_broadcasted_holder_watch_outputs(&self, holder_tx: &HolderSignedTx, commitment_tx: &Transaction) -> Vec<(u32, TxOut)> {
1764 let mut watch_outputs = Vec::with_capacity(holder_tx.htlc_outputs.len());
1765 for &(ref htlc, _, _) in holder_tx.htlc_outputs.iter() {
1766 if let Some(transaction_output_index) = htlc.transaction_output_index {
1767 watch_outputs.push((transaction_output_index, commitment_tx.output[transaction_output_index as usize].clone()));
1773 /// Attempts to claim any claimable HTLCs in a commitment transaction which was not (yet)
1774 /// revoked using data in holder_claimable_outpoints.
1775 /// Should not be used if check_spend_revoked_transaction succeeds.
1776 fn check_spend_holder_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) -> (Vec<PackageTemplate>, TransactionOutputs) where L::Target: Logger {
1777 let commitment_txid = tx.txid();
1778 let mut claim_requests = Vec::new();
1779 let mut watch_outputs = Vec::new();
1781 macro_rules! append_onchain_update {
1782 ($updates: expr, $to_watch: expr) => {
1783 claim_requests = $updates.0;
1784 self.broadcasted_holder_revokable_script = $updates.1;
1785 watch_outputs.append(&mut $to_watch);
1789 // HTLCs set may differ between last and previous holder commitment txn, in case of one them hitting chain, ensure we cancel all HTLCs backward
1790 let mut is_holder_tx = false;
1792 if self.current_holder_commitment_tx.txid == commitment_txid {
1793 is_holder_tx = true;
1794 log_info!(logger, "Got broadcast of latest holder commitment tx {}, searching for available HTLCs to claim", commitment_txid);
1795 let res = self.get_broadcasted_holder_claims(&self.current_holder_commitment_tx, height);
1796 let mut to_watch = self.get_broadcasted_holder_watch_outputs(&self.current_holder_commitment_tx, tx);
1797 append_onchain_update!(res, to_watch);
1798 fail_unbroadcast_htlcs!(self, "latest holder", height, self.current_holder_commitment_tx.htlc_outputs.iter().map(|(a, _, c)| (a, c.as_ref())), logger);
1799 } else if let &Some(ref holder_tx) = &self.prev_holder_signed_commitment_tx {
1800 if holder_tx.txid == commitment_txid {
1801 is_holder_tx = true;
1802 log_info!(logger, "Got broadcast of previous holder commitment tx {}, searching for available HTLCs to claim", commitment_txid);
1803 let res = self.get_broadcasted_holder_claims(holder_tx, height);
1804 let mut to_watch = self.get_broadcasted_holder_watch_outputs(holder_tx, tx);
1805 append_onchain_update!(res, to_watch);
1806 fail_unbroadcast_htlcs!(self, "previous holder", height, holder_tx.htlc_outputs.iter().map(|(a, _, c)| (a, c.as_ref())), logger);
1813 (claim_requests, (commitment_txid, watch_outputs))
1816 pub fn get_latest_holder_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
1817 log_debug!(logger, "Getting signed latest holder commitment transaction!");
1818 self.holder_tx_signed = true;
1819 let commitment_tx = self.onchain_tx_handler.get_fully_signed_holder_tx(&self.funding_redeemscript);
1820 let txid = commitment_tx.txid();
1821 let mut holder_transactions = vec![commitment_tx];
1822 for htlc in self.current_holder_commitment_tx.htlc_outputs.iter() {
1823 if let Some(vout) = htlc.0.transaction_output_index {
1824 let preimage = if !htlc.0.offered {
1825 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
1826 // We can't build an HTLC-Success transaction without the preimage
1829 } else if htlc.0.cltv_expiry > self.best_block.height() + 1 {
1830 // Don't broadcast HTLC-Timeout transactions immediately as they don't meet the
1831 // current locktime requirements on-chain. We will broadcast them in
1832 // `block_confirmed` when `should_broadcast_holder_commitment_txn` returns true.
1833 // Note that we add + 1 as transactions are broadcastable when they can be
1834 // confirmed in the next block.
1837 if let Some(htlc_tx) = self.onchain_tx_handler.get_fully_signed_htlc_tx(
1838 &::bitcoin::OutPoint { txid, vout }, &preimage) {
1839 holder_transactions.push(htlc_tx);
1843 // 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.
1844 // The data will be re-generated and tracked in check_spend_holder_transaction if we get a confirmation.
1848 #[cfg(any(test,feature = "unsafe_revoked_tx_signing"))]
1849 /// Note that this includes possibly-locktimed-in-the-future transactions!
1850 fn unsafe_get_latest_holder_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
1851 log_debug!(logger, "Getting signed copy of latest holder commitment transaction!");
1852 let commitment_tx = self.onchain_tx_handler.get_fully_signed_copy_holder_tx(&self.funding_redeemscript);
1853 let txid = commitment_tx.txid();
1854 let mut holder_transactions = vec![commitment_tx];
1855 for htlc in self.current_holder_commitment_tx.htlc_outputs.iter() {
1856 if let Some(vout) = htlc.0.transaction_output_index {
1857 let preimage = if !htlc.0.offered {
1858 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
1859 // We can't build an HTLC-Success transaction without the preimage
1863 if let Some(htlc_tx) = self.onchain_tx_handler.unsafe_get_fully_signed_htlc_tx(
1864 &::bitcoin::OutPoint { txid, vout }, &preimage) {
1865 holder_transactions.push(htlc_tx);
1872 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>
1873 where B::Target: BroadcasterInterface,
1874 F::Target: FeeEstimator,
1877 let block_hash = header.block_hash();
1878 log_trace!(logger, "New best block {} at height {}", block_hash, height);
1879 self.best_block = BestBlock::new(block_hash, height);
1881 self.transactions_confirmed(header, txdata, height, broadcaster, fee_estimator, logger)
1884 fn best_block_updated<B: Deref, F: Deref, L: Deref>(
1886 header: &BlockHeader,
1891 ) -> Vec<TransactionOutputs>
1893 B::Target: BroadcasterInterface,
1894 F::Target: FeeEstimator,
1897 let block_hash = header.block_hash();
1898 log_trace!(logger, "New best block {} at height {}", block_hash, height);
1900 if height > self.best_block.height() {
1901 self.best_block = BestBlock::new(block_hash, height);
1902 self.block_confirmed(height, vec![], vec![], vec![], &broadcaster, &fee_estimator, &logger)
1903 } else if block_hash != self.best_block.block_hash() {
1904 self.best_block = BestBlock::new(block_hash, height);
1905 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| entry.height <= height);
1906 self.onchain_tx_handler.block_disconnected(height + 1, broadcaster, fee_estimator, logger);
1908 } else { Vec::new() }
1911 fn transactions_confirmed<B: Deref, F: Deref, L: Deref>(
1913 header: &BlockHeader,
1914 txdata: &TransactionData,
1919 ) -> Vec<TransactionOutputs>
1921 B::Target: BroadcasterInterface,
1922 F::Target: FeeEstimator,
1925 let txn_matched = self.filter_block(txdata);
1926 for tx in &txn_matched {
1927 let mut output_val = 0;
1928 for out in tx.output.iter() {
1929 if out.value > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
1930 output_val += out.value;
1931 if output_val > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
1935 let block_hash = header.block_hash();
1936 log_trace!(logger, "Block {} at height {} connected with {} txn matched", block_hash, height, txn_matched.len());
1938 let mut watch_outputs = Vec::new();
1939 let mut claimable_outpoints = Vec::new();
1940 for tx in &txn_matched {
1941 if tx.input.len() == 1 {
1942 // Assuming our keys were not leaked (in which case we're screwed no matter what),
1943 // commitment transactions and HTLC transactions will all only ever have one input,
1944 // which is an easy way to filter out any potential non-matching txn for lazy
1946 let prevout = &tx.input[0].previous_output;
1947 if prevout.txid == self.funding_info.0.txid && prevout.vout == self.funding_info.0.index as u32 {
1948 if (tx.input[0].sequence >> 8*3) as u8 == 0x80 && (tx.lock_time >> 8*3) as u8 == 0x20 {
1949 let (mut new_outpoints, new_outputs) = self.check_spend_counterparty_transaction(&tx, height, &logger);
1950 if !new_outputs.1.is_empty() {
1951 watch_outputs.push(new_outputs);
1953 if new_outpoints.is_empty() {
1954 let (mut new_outpoints, new_outputs) = self.check_spend_holder_transaction(&tx, height, &logger);
1955 if !new_outputs.1.is_empty() {
1956 watch_outputs.push(new_outputs);
1958 claimable_outpoints.append(&mut new_outpoints);
1960 claimable_outpoints.append(&mut new_outpoints);
1963 if let Some(&commitment_number) = self.counterparty_commitment_txn_on_chain.get(&prevout.txid) {
1964 let (mut new_outpoints, new_outputs_option) = self.check_spend_counterparty_htlc(&tx, commitment_number, height, &logger);
1965 claimable_outpoints.append(&mut new_outpoints);
1966 if let Some(new_outputs) = new_outputs_option {
1967 watch_outputs.push(new_outputs);
1972 // While all commitment/HTLC-Success/HTLC-Timeout transactions have one input, HTLCs
1973 // can also be resolved in a few other ways which can have more than one output. Thus,
1974 // we call is_resolving_htlc_output here outside of the tx.input.len() == 1 check.
1975 self.is_resolving_htlc_output(&tx, height, &logger);
1977 self.is_paying_spendable_output(&tx, height, &logger);
1980 if height > self.best_block.height() {
1981 self.best_block = BestBlock::new(block_hash, height);
1984 self.block_confirmed(height, txn_matched, watch_outputs, claimable_outpoints, &broadcaster, &fee_estimator, &logger)
1987 /// Update state for new block(s)/transaction(s) confirmed. Note that the caller must update
1988 /// `self.best_block` before calling if a new best blockchain tip is available. More
1989 /// concretely, `self.best_block` must never be at a lower height than `conf_height`, avoiding
1990 /// complexity especially in `OnchainTx::update_claims_view`.
1992 /// `conf_height` should be set to the height at which any new transaction(s)/block(s) were
1993 /// confirmed at, even if it is not the current best height.
1994 fn block_confirmed<B: Deref, F: Deref, L: Deref>(
1997 txn_matched: Vec<&Transaction>,
1998 mut watch_outputs: Vec<TransactionOutputs>,
1999 mut claimable_outpoints: Vec<PackageTemplate>,
2003 ) -> Vec<TransactionOutputs>
2005 B::Target: BroadcasterInterface,
2006 F::Target: FeeEstimator,
2009 debug_assert!(self.best_block.height() >= conf_height);
2011 let should_broadcast = self.should_broadcast_holder_commitment_txn(logger);
2012 if should_broadcast {
2013 let funding_outp = HolderFundingOutput::build(self.funding_redeemscript.clone());
2014 let commitment_package = PackageTemplate::build_package(self.funding_info.0.txid.clone(), self.funding_info.0.index as u32, PackageSolvingData::HolderFundingOutput(funding_outp), self.best_block.height(), false, self.best_block.height());
2015 claimable_outpoints.push(commitment_package);
2016 self.pending_monitor_events.push(MonitorEvent::CommitmentTxBroadcasted(self.funding_info.0));
2017 let commitment_tx = self.onchain_tx_handler.get_fully_signed_holder_tx(&self.funding_redeemscript);
2018 self.holder_tx_signed = true;
2019 // Because we're broadcasting a commitment transaction, we should construct the package
2020 // assuming it gets confirmed in the next block. Sadly, we have code which considers
2021 // "not yet confirmed" things as discardable, so we cannot do that here.
2022 let (mut new_outpoints, _) = self.get_broadcasted_holder_claims(&self.current_holder_commitment_tx, self.best_block.height());
2023 let new_outputs = self.get_broadcasted_holder_watch_outputs(&self.current_holder_commitment_tx, &commitment_tx);
2024 if !new_outputs.is_empty() {
2025 watch_outputs.push((self.current_holder_commitment_tx.txid.clone(), new_outputs));
2027 claimable_outpoints.append(&mut new_outpoints);
2030 // Find which on-chain events have reached their confirmation threshold.
2031 let onchain_events_awaiting_threshold_conf =
2032 self.onchain_events_awaiting_threshold_conf.drain(..).collect::<Vec<_>>();
2033 let mut onchain_events_reaching_threshold_conf = Vec::new();
2034 for entry in onchain_events_awaiting_threshold_conf {
2035 if entry.has_reached_confirmation_threshold(&self.best_block) {
2036 onchain_events_reaching_threshold_conf.push(entry);
2038 self.onchain_events_awaiting_threshold_conf.push(entry);
2042 // Used to check for duplicate HTLC resolutions.
2043 #[cfg(debug_assertions)]
2044 let unmatured_htlcs: Vec<_> = self.onchain_events_awaiting_threshold_conf
2046 .filter_map(|entry| match &entry.event {
2047 OnchainEvent::HTLCUpdate { source, .. } => Some(source),
2048 OnchainEvent::MaturingOutput { .. } => None,
2051 #[cfg(debug_assertions)]
2052 let mut matured_htlcs = Vec::new();
2054 // Produce actionable events from on-chain events having reached their threshold.
2055 for entry in onchain_events_reaching_threshold_conf.drain(..) {
2057 OnchainEvent::HTLCUpdate { ref source, payment_hash, onchain_value_satoshis } => {
2058 // Check for duplicate HTLC resolutions.
2059 #[cfg(debug_assertions)]
2062 unmatured_htlcs.iter().find(|&htlc| htlc == &source).is_none(),
2063 "An unmature HTLC transaction conflicts with a maturing one; failed to \
2064 call either transaction_unconfirmed for the conflicting transaction \
2065 or block_disconnected for a block containing it.");
2067 matured_htlcs.iter().find(|&htlc| htlc == source).is_none(),
2068 "A matured HTLC transaction conflicts with a maturing one; failed to \
2069 call either transaction_unconfirmed for the conflicting transaction \
2070 or block_disconnected for a block containing it.");
2071 matured_htlcs.push(source.clone());
2074 log_debug!(logger, "HTLC {} failure update has got enough confirmations to be passed upstream", log_bytes!(payment_hash.0));
2075 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
2077 payment_preimage: None,
2078 source: source.clone(),
2079 onchain_value_satoshis,
2082 OnchainEvent::MaturingOutput { descriptor } => {
2083 log_debug!(logger, "Descriptor {} has got enough confirmations to be passed upstream", log_spendable!(descriptor));
2084 self.pending_events.push(Event::SpendableOutputs {
2085 outputs: vec![descriptor]
2091 self.onchain_tx_handler.update_claims_view(&txn_matched, claimable_outpoints, conf_height, self.best_block.height(), broadcaster, fee_estimator, logger);
2093 // Determine new outputs to watch by comparing against previously known outputs to watch,
2094 // updating the latter in the process.
2095 watch_outputs.retain(|&(ref txid, ref txouts)| {
2096 let idx_and_scripts = txouts.iter().map(|o| (o.0, o.1.script_pubkey.clone())).collect();
2097 self.outputs_to_watch.insert(txid.clone(), idx_and_scripts).is_none()
2101 // If we see a transaction for which we registered outputs previously,
2102 // make sure the registered scriptpubkey at the expected index match
2103 // the actual transaction output one. We failed this case before #653.
2104 for tx in &txn_matched {
2105 if let Some(outputs) = self.get_outputs_to_watch().get(&tx.txid()) {
2106 for idx_and_script in outputs.iter() {
2107 assert!((idx_and_script.0 as usize) < tx.output.len());
2108 assert_eq!(tx.output[idx_and_script.0 as usize].script_pubkey, idx_and_script.1);
2116 pub fn block_disconnected<B: Deref, F: Deref, L: Deref>(&mut self, header: &BlockHeader, height: u32, broadcaster: B, fee_estimator: F, logger: L)
2117 where B::Target: BroadcasterInterface,
2118 F::Target: FeeEstimator,
2121 log_trace!(logger, "Block {} at height {} disconnected", header.block_hash(), height);
2124 //- htlc update there as failure-trigger tx (revoked commitment tx, non-revoked commitment tx, HTLC-timeout tx) has been disconnected
2125 //- maturing spendable output has transaction paying us has been disconnected
2126 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| entry.height < height);
2128 self.onchain_tx_handler.block_disconnected(height, broadcaster, fee_estimator, logger);
2130 self.best_block = BestBlock::new(header.prev_blockhash, height - 1);
2133 fn transaction_unconfirmed<B: Deref, F: Deref, L: Deref>(
2140 B::Target: BroadcasterInterface,
2141 F::Target: FeeEstimator,
2144 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| entry.txid != *txid);
2145 self.onchain_tx_handler.transaction_unconfirmed(txid, broadcaster, fee_estimator, logger);
2148 /// Filters a block's `txdata` for transactions spending watched outputs or for any child
2149 /// transactions thereof.
2150 fn filter_block<'a>(&self, txdata: &TransactionData<'a>) -> Vec<&'a Transaction> {
2151 let mut matched_txn = HashSet::new();
2152 txdata.iter().filter(|&&(_, tx)| {
2153 let mut matches = self.spends_watched_output(tx);
2154 for input in tx.input.iter() {
2155 if matches { break; }
2156 if matched_txn.contains(&input.previous_output.txid) {
2161 matched_txn.insert(tx.txid());
2164 }).map(|(_, tx)| *tx).collect()
2167 /// Checks if a given transaction spends any watched outputs.
2168 fn spends_watched_output(&self, tx: &Transaction) -> bool {
2169 for input in tx.input.iter() {
2170 if let Some(outputs) = self.get_outputs_to_watch().get(&input.previous_output.txid) {
2171 for (idx, _script_pubkey) in outputs.iter() {
2172 if *idx == input.previous_output.vout {
2175 // If the expected script is a known type, check that the witness
2176 // appears to be spending the correct type (ie that the match would
2177 // actually succeed in BIP 158/159-style filters).
2178 if _script_pubkey.is_v0_p2wsh() {
2179 assert_eq!(&bitcoin::Address::p2wsh(&Script::from(input.witness.last().unwrap().clone()), bitcoin::Network::Bitcoin).script_pubkey(), _script_pubkey);
2180 } else if _script_pubkey.is_v0_p2wpkh() {
2181 assert_eq!(&bitcoin::Address::p2wpkh(&bitcoin::PublicKey::from_slice(&input.witness.last().unwrap()).unwrap(), bitcoin::Network::Bitcoin).unwrap().script_pubkey(), _script_pubkey);
2182 } else { panic!(); }
2193 fn should_broadcast_holder_commitment_txn<L: Deref>(&self, logger: &L) -> bool where L::Target: Logger {
2194 // We need to consider all HTLCs which are:
2195 // * in any unrevoked counterparty commitment transaction, as they could broadcast said
2196 // transactions and we'd end up in a race, or
2197 // * are in our latest holder commitment transaction, as this is the thing we will
2198 // broadcast if we go on-chain.
2199 // Note that we consider HTLCs which were below dust threshold here - while they don't
2200 // strictly imply that we need to fail the channel, we need to go ahead and fail them back
2201 // to the source, and if we don't fail the channel we will have to ensure that the next
2202 // updates that peer sends us are update_fails, failing the channel if not. It's probably
2203 // easier to just fail the channel as this case should be rare enough anyway.
2204 let height = self.best_block.height();
2205 macro_rules! scan_commitment {
2206 ($htlcs: expr, $holder_tx: expr) => {
2207 for ref htlc in $htlcs {
2208 // For inbound HTLCs which we know the preimage for, we have to ensure we hit the
2209 // chain with enough room to claim the HTLC without our counterparty being able to
2210 // time out the HTLC first.
2211 // For outbound HTLCs which our counterparty hasn't failed/claimed, our primary
2212 // concern is being able to claim the corresponding inbound HTLC (on another
2213 // channel) before it expires. In fact, we don't even really care if our
2214 // counterparty here claims such an outbound HTLC after it expired as long as we
2215 // can still claim the corresponding HTLC. Thus, to avoid needlessly hitting the
2216 // chain when our counterparty is waiting for expiration to off-chain fail an HTLC
2217 // we give ourselves a few blocks of headroom after expiration before going
2218 // on-chain for an expired HTLC.
2219 // Note that, to avoid a potential attack whereby a node delays claiming an HTLC
2220 // from us until we've reached the point where we go on-chain with the
2221 // corresponding inbound HTLC, we must ensure that outbound HTLCs go on chain at
2222 // least CLTV_CLAIM_BUFFER blocks prior to the inbound HTLC.
2223 // aka outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS == height - CLTV_CLAIM_BUFFER
2224 // inbound_cltv == height + CLTV_CLAIM_BUFFER
2225 // outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS + CLTV_CLAIM_BUFFER <= inbound_cltv - CLTV_CLAIM_BUFFER
2226 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= inbound_cltv - outbound_cltv
2227 // CLTV_EXPIRY_DELTA <= inbound_cltv - outbound_cltv (by check in ChannelManager::decode_update_add_htlc_onion)
2228 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= CLTV_EXPIRY_DELTA
2229 // The final, above, condition is checked for statically in channelmanager
2230 // with CHECK_CLTV_EXPIRY_SANITY_2.
2231 let htlc_outbound = $holder_tx == htlc.offered;
2232 if ( htlc_outbound && htlc.cltv_expiry + LATENCY_GRACE_PERIOD_BLOCKS <= height) ||
2233 (!htlc_outbound && htlc.cltv_expiry <= height + CLTV_CLAIM_BUFFER && self.payment_preimages.contains_key(&htlc.payment_hash)) {
2234 log_info!(logger, "Force-closing channel due to {} HTLC timeout, HTLC expiry is {}", if htlc_outbound { "outbound" } else { "inbound "}, htlc.cltv_expiry);
2241 scan_commitment!(self.current_holder_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, _)| a), true);
2243 if let Some(ref txid) = self.current_counterparty_commitment_txid {
2244 if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(txid) {
2245 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
2248 if let Some(ref txid) = self.prev_counterparty_commitment_txid {
2249 if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(txid) {
2250 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
2257 /// Check if any transaction broadcasted is resolving HTLC output by a success or timeout on a holder
2258 /// or counterparty commitment tx, if so send back the source, preimage if found and payment_hash of resolved HTLC
2259 fn is_resolving_htlc_output<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) where L::Target: Logger {
2260 'outer_loop: for input in &tx.input {
2261 let mut payment_data = None;
2262 let revocation_sig_claim = (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC) && input.witness[1].len() == 33)
2263 || (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::AcceptedHTLC) && input.witness[1].len() == 33);
2264 let accepted_preimage_claim = input.witness.len() == 5 && HTLCType::scriptlen_to_htlctype(input.witness[4].len()) == Some(HTLCType::AcceptedHTLC);
2265 let offered_preimage_claim = input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC);
2267 macro_rules! log_claim {
2268 ($tx_info: expr, $holder_tx: expr, $htlc: expr, $source_avail: expr) => {
2269 // We found the output in question, but aren't failing it backwards
2270 // as we have no corresponding source and no valid counterparty commitment txid
2271 // to try a weak source binding with same-hash, same-value still-valid offered HTLC.
2272 // This implies either it is an inbound HTLC or an outbound HTLC on a revoked transaction.
2273 let outbound_htlc = $holder_tx == $htlc.offered;
2274 if ($holder_tx && revocation_sig_claim) ||
2275 (outbound_htlc && !$source_avail && (accepted_preimage_claim || offered_preimage_claim)) {
2276 log_error!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}!",
2277 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
2278 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
2279 if revocation_sig_claim { "revocation sig" } else { "preimage claim after we'd passed the HTLC resolution back" });
2281 log_info!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}",
2282 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
2283 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
2284 if revocation_sig_claim { "revocation sig" } else if accepted_preimage_claim || offered_preimage_claim { "preimage" } else { "timeout" });
2289 macro_rules! check_htlc_valid_counterparty {
2290 ($counterparty_txid: expr, $htlc_output: expr) => {
2291 if let Some(txid) = $counterparty_txid {
2292 for &(ref pending_htlc, ref pending_source) in self.counterparty_claimable_outpoints.get(&txid).unwrap() {
2293 if pending_htlc.payment_hash == $htlc_output.payment_hash && pending_htlc.amount_msat == $htlc_output.amount_msat {
2294 if let &Some(ref source) = pending_source {
2295 log_claim!("revoked counterparty commitment tx", false, pending_htlc, true);
2296 payment_data = Some(((**source).clone(), $htlc_output.payment_hash, $htlc_output.amount_msat));
2305 macro_rules! scan_commitment {
2306 ($htlcs: expr, $tx_info: expr, $holder_tx: expr) => {
2307 for (ref htlc_output, source_option) in $htlcs {
2308 if Some(input.previous_output.vout) == htlc_output.transaction_output_index {
2309 if let Some(ref source) = source_option {
2310 log_claim!($tx_info, $holder_tx, htlc_output, true);
2311 // We have a resolution of an HTLC either from one of our latest
2312 // holder commitment transactions or an unrevoked counterparty commitment
2313 // transaction. This implies we either learned a preimage, the HTLC
2314 // has timed out, or we screwed up. In any case, we should now
2315 // resolve the source HTLC with the original sender.
2316 payment_data = Some(((*source).clone(), htlc_output.payment_hash, htlc_output.amount_msat));
2317 } else if !$holder_tx {
2318 check_htlc_valid_counterparty!(self.current_counterparty_commitment_txid, htlc_output);
2319 if payment_data.is_none() {
2320 check_htlc_valid_counterparty!(self.prev_counterparty_commitment_txid, htlc_output);
2323 if payment_data.is_none() {
2324 log_claim!($tx_info, $holder_tx, htlc_output, false);
2325 continue 'outer_loop;
2332 if input.previous_output.txid == self.current_holder_commitment_tx.txid {
2333 scan_commitment!(self.current_holder_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
2334 "our latest holder commitment tx", true);
2336 if let Some(ref prev_holder_signed_commitment_tx) = self.prev_holder_signed_commitment_tx {
2337 if input.previous_output.txid == prev_holder_signed_commitment_tx.txid {
2338 scan_commitment!(prev_holder_signed_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
2339 "our previous holder commitment tx", true);
2342 if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(&input.previous_output.txid) {
2343 scan_commitment!(htlc_outputs.iter().map(|&(ref a, ref b)| (a, (b.as_ref().clone()).map(|boxed| &**boxed))),
2344 "counterparty commitment tx", false);
2347 // Check that scan_commitment, above, decided there is some source worth relaying an
2348 // HTLC resolution backwards to and figure out whether we learned a preimage from it.
2349 if let Some((source, payment_hash, amount_msat)) = payment_data {
2350 let mut payment_preimage = PaymentPreimage([0; 32]);
2351 if accepted_preimage_claim {
2352 if !self.pending_monitor_events.iter().any(
2353 |update| if let &MonitorEvent::HTLCEvent(ref upd) = update { upd.source == source } else { false }) {
2354 payment_preimage.0.copy_from_slice(&input.witness[3]);
2355 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
2357 payment_preimage: Some(payment_preimage),
2359 onchain_value_satoshis: Some(amount_msat / 1000),
2362 } else if offered_preimage_claim {
2363 if !self.pending_monitor_events.iter().any(
2364 |update| if let &MonitorEvent::HTLCEvent(ref upd) = update {
2365 upd.source == source
2367 payment_preimage.0.copy_from_slice(&input.witness[1]);
2368 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
2370 payment_preimage: Some(payment_preimage),
2372 onchain_value_satoshis: Some(amount_msat / 1000),
2376 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| {
2377 if entry.height != height { return true; }
2379 OnchainEvent::HTLCUpdate { source: ref htlc_source, .. } => {
2380 *htlc_source != source
2385 let entry = OnchainEventEntry {
2388 event: OnchainEvent::HTLCUpdate {
2389 source, payment_hash,
2390 onchain_value_satoshis: Some(amount_msat / 1000),
2393 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());
2394 self.onchain_events_awaiting_threshold_conf.push(entry);
2400 /// Check if any transaction broadcasted is paying fund back to some address we can assume to own
2401 fn is_paying_spendable_output<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) where L::Target: Logger {
2402 let mut spendable_output = None;
2403 for (i, outp) in tx.output.iter().enumerate() { // There is max one spendable output for any channel tx, including ones generated by us
2404 if i > ::core::u16::MAX as usize {
2405 // While it is possible that an output exists on chain which is greater than the
2406 // 2^16th output in a given transaction, this is only possible if the output is not
2407 // in a lightning transaction and was instead placed there by some third party who
2408 // wishes to give us money for no reason.
2409 // Namely, any lightning transactions which we pre-sign will never have anywhere
2410 // near 2^16 outputs both because such transactions must have ~2^16 outputs who's
2411 // scripts are not longer than one byte in length and because they are inherently
2412 // non-standard due to their size.
2413 // Thus, it is completely safe to ignore such outputs, and while it may result in
2414 // us ignoring non-lightning fund to us, that is only possible if someone fills
2415 // nearly a full block with garbage just to hit this case.
2418 if outp.script_pubkey == self.destination_script {
2419 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
2420 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
2421 output: outp.clone(),
2425 if let Some(ref broadcasted_holder_revokable_script) = self.broadcasted_holder_revokable_script {
2426 if broadcasted_holder_revokable_script.0 == outp.script_pubkey {
2427 spendable_output = Some(SpendableOutputDescriptor::DelayedPaymentOutput(DelayedPaymentOutputDescriptor {
2428 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
2429 per_commitment_point: broadcasted_holder_revokable_script.1,
2430 to_self_delay: self.on_holder_tx_csv,
2431 output: outp.clone(),
2432 revocation_pubkey: broadcasted_holder_revokable_script.2.clone(),
2433 channel_keys_id: self.channel_keys_id,
2434 channel_value_satoshis: self.channel_value_satoshis,
2439 if self.counterparty_payment_script == outp.script_pubkey {
2440 spendable_output = Some(SpendableOutputDescriptor::StaticPaymentOutput(StaticPaymentOutputDescriptor {
2441 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
2442 output: outp.clone(),
2443 channel_keys_id: self.channel_keys_id,
2444 channel_value_satoshis: self.channel_value_satoshis,
2448 if outp.script_pubkey == self.shutdown_script {
2449 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
2450 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
2451 output: outp.clone(),
2456 if let Some(spendable_output) = spendable_output {
2457 let entry = OnchainEventEntry {
2460 event: OnchainEvent::MaturingOutput { descriptor: spendable_output.clone() },
2462 log_info!(logger, "Received spendable output {}, spendable at height {}", log_spendable!(spendable_output), entry.confirmation_threshold());
2463 self.onchain_events_awaiting_threshold_conf.push(entry);
2468 /// `Persist` defines behavior for persisting channel monitors: this could mean
2469 /// writing once to disk, and/or uploading to one or more backup services.
2471 /// Note that for every new monitor, you **must** persist the new `ChannelMonitor`
2472 /// to disk/backups. And, on every update, you **must** persist either the
2473 /// `ChannelMonitorUpdate` or the updated monitor itself. Otherwise, there is risk
2474 /// of situations such as revoking a transaction, then crashing before this
2475 /// revocation can be persisted, then unintentionally broadcasting a revoked
2476 /// transaction and losing money. This is a risk because previous channel states
2477 /// are toxic, so it's important that whatever channel state is persisted is
2478 /// kept up-to-date.
2479 pub trait Persist<ChannelSigner: Sign> {
2480 /// Persist a new channel's data. The data can be stored any way you want, but
2481 /// the identifier provided by Rust-Lightning is the channel's outpoint (and
2482 /// it is up to you to maintain a correct mapping between the outpoint and the
2483 /// stored channel data). Note that you **must** persist every new monitor to
2484 /// disk. See the `Persist` trait documentation for more details.
2486 /// See [`ChannelMonitor::write`] for writing out a `ChannelMonitor`,
2487 /// and [`ChannelMonitorUpdateErr`] for requirements when returning errors.
2488 fn persist_new_channel(&self, id: OutPoint, data: &ChannelMonitor<ChannelSigner>) -> Result<(), ChannelMonitorUpdateErr>;
2490 /// Update one channel's data. The provided `ChannelMonitor` has already
2491 /// applied the given update.
2493 /// Note that on every update, you **must** persist either the
2494 /// `ChannelMonitorUpdate` or the updated monitor itself to disk/backups. See
2495 /// the `Persist` trait documentation for more details.
2497 /// If an implementer chooses to persist the updates only, they need to make
2498 /// sure that all the updates are applied to the `ChannelMonitors` *before*
2499 /// the set of channel monitors is given to the `ChannelManager`
2500 /// deserialization routine. See [`ChannelMonitor::update_monitor`] for
2501 /// applying a monitor update to a monitor. If full `ChannelMonitors` are
2502 /// persisted, then there is no need to persist individual updates.
2504 /// Note that there could be a performance tradeoff between persisting complete
2505 /// channel monitors on every update vs. persisting only updates and applying
2506 /// them in batches. The size of each monitor grows `O(number of state updates)`
2507 /// whereas updates are small and `O(1)`.
2509 /// See [`ChannelMonitor::write`] for writing out a `ChannelMonitor`,
2510 /// [`ChannelMonitorUpdate::write`] for writing out an update, and
2511 /// [`ChannelMonitorUpdateErr`] for requirements when returning errors.
2512 fn update_persisted_channel(&self, id: OutPoint, update: &ChannelMonitorUpdate, data: &ChannelMonitor<ChannelSigner>) -> Result<(), ChannelMonitorUpdateErr>;
2515 impl<Signer: Sign, T: Deref, F: Deref, L: Deref> chain::Listen for (ChannelMonitor<Signer>, T, F, L)
2517 T::Target: BroadcasterInterface,
2518 F::Target: FeeEstimator,
2521 fn block_connected(&self, block: &Block, height: u32) {
2522 let txdata: Vec<_> = block.txdata.iter().enumerate().collect();
2523 self.0.block_connected(&block.header, &txdata, height, &*self.1, &*self.2, &*self.3);
2526 fn block_disconnected(&self, header: &BlockHeader, height: u32) {
2527 self.0.block_disconnected(header, height, &*self.1, &*self.2, &*self.3);
2531 impl<Signer: Sign, T: Deref, F: Deref, L: Deref> chain::Confirm for (ChannelMonitor<Signer>, T, F, L)
2533 T::Target: BroadcasterInterface,
2534 F::Target: FeeEstimator,
2537 fn transactions_confirmed(&self, header: &BlockHeader, txdata: &TransactionData, height: u32) {
2538 self.0.transactions_confirmed(header, txdata, height, &*self.1, &*self.2, &*self.3);
2541 fn transaction_unconfirmed(&self, txid: &Txid) {
2542 self.0.transaction_unconfirmed(txid, &*self.1, &*self.2, &*self.3);
2545 fn best_block_updated(&self, header: &BlockHeader, height: u32) {
2546 self.0.best_block_updated(header, height, &*self.1, &*self.2, &*self.3);
2549 fn get_relevant_txids(&self) -> Vec<Txid> {
2550 self.0.get_relevant_txids()
2554 const MAX_ALLOC_SIZE: usize = 64*1024;
2556 impl<'a, Signer: Sign, K: KeysInterface<Signer = Signer>> ReadableArgs<&'a K>
2557 for (BlockHash, ChannelMonitor<Signer>) {
2558 fn read<R: io::Read>(reader: &mut R, keys_manager: &'a K) -> Result<Self, DecodeError> {
2559 macro_rules! unwrap_obj {
2563 Err(_) => return Err(DecodeError::InvalidValue),
2568 let _ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
2570 let latest_update_id: u64 = Readable::read(reader)?;
2571 let commitment_transaction_number_obscure_factor = <U48 as Readable>::read(reader)?.0;
2573 let destination_script = Readable::read(reader)?;
2574 let broadcasted_holder_revokable_script = match <u8 as Readable>::read(reader)? {
2576 let revokable_address = Readable::read(reader)?;
2577 let per_commitment_point = Readable::read(reader)?;
2578 let revokable_script = Readable::read(reader)?;
2579 Some((revokable_address, per_commitment_point, revokable_script))
2582 _ => return Err(DecodeError::InvalidValue),
2584 let counterparty_payment_script = Readable::read(reader)?;
2585 let shutdown_script = Readable::read(reader)?;
2587 let channel_keys_id = Readable::read(reader)?;
2588 let holder_revocation_basepoint = Readable::read(reader)?;
2589 // Technically this can fail and serialize fail a round-trip, but only for serialization of
2590 // barely-init'd ChannelMonitors that we can't do anything with.
2591 let outpoint = OutPoint {
2592 txid: Readable::read(reader)?,
2593 index: Readable::read(reader)?,
2595 let funding_info = (outpoint, Readable::read(reader)?);
2596 let current_counterparty_commitment_txid = Readable::read(reader)?;
2597 let prev_counterparty_commitment_txid = Readable::read(reader)?;
2599 let counterparty_tx_cache = Readable::read(reader)?;
2600 let funding_redeemscript = Readable::read(reader)?;
2601 let channel_value_satoshis = Readable::read(reader)?;
2603 let their_cur_revocation_points = {
2604 let first_idx = <U48 as Readable>::read(reader)?.0;
2608 let first_point = Readable::read(reader)?;
2609 let second_point_slice: [u8; 33] = Readable::read(reader)?;
2610 if second_point_slice[0..32] == [0; 32] && second_point_slice[32] == 0 {
2611 Some((first_idx, first_point, None))
2613 Some((first_idx, first_point, Some(unwrap_obj!(PublicKey::from_slice(&second_point_slice)))))
2618 let on_holder_tx_csv: u16 = Readable::read(reader)?;
2620 let commitment_secrets = Readable::read(reader)?;
2622 macro_rules! read_htlc_in_commitment {
2625 let offered: bool = Readable::read(reader)?;
2626 let amount_msat: u64 = Readable::read(reader)?;
2627 let cltv_expiry: u32 = Readable::read(reader)?;
2628 let payment_hash: PaymentHash = Readable::read(reader)?;
2629 let transaction_output_index: Option<u32> = Readable::read(reader)?;
2631 HTLCOutputInCommitment {
2632 offered, amount_msat, cltv_expiry, payment_hash, transaction_output_index
2638 let counterparty_claimable_outpoints_len: u64 = Readable::read(reader)?;
2639 let mut counterparty_claimable_outpoints = HashMap::with_capacity(cmp::min(counterparty_claimable_outpoints_len as usize, MAX_ALLOC_SIZE / 64));
2640 for _ in 0..counterparty_claimable_outpoints_len {
2641 let txid: Txid = Readable::read(reader)?;
2642 let htlcs_count: u64 = Readable::read(reader)?;
2643 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
2644 for _ in 0..htlcs_count {
2645 htlcs.push((read_htlc_in_commitment!(), <Option<HTLCSource> as Readable>::read(reader)?.map(|o: HTLCSource| Box::new(o))));
2647 if let Some(_) = counterparty_claimable_outpoints.insert(txid, htlcs) {
2648 return Err(DecodeError::InvalidValue);
2652 let counterparty_commitment_txn_on_chain_len: u64 = Readable::read(reader)?;
2653 let mut counterparty_commitment_txn_on_chain = HashMap::with_capacity(cmp::min(counterparty_commitment_txn_on_chain_len as usize, MAX_ALLOC_SIZE / 32));
2654 for _ in 0..counterparty_commitment_txn_on_chain_len {
2655 let txid: Txid = Readable::read(reader)?;
2656 let commitment_number = <U48 as Readable>::read(reader)?.0;
2657 if let Some(_) = counterparty_commitment_txn_on_chain.insert(txid, commitment_number) {
2658 return Err(DecodeError::InvalidValue);
2662 let counterparty_hash_commitment_number_len: u64 = Readable::read(reader)?;
2663 let mut counterparty_hash_commitment_number = HashMap::with_capacity(cmp::min(counterparty_hash_commitment_number_len as usize, MAX_ALLOC_SIZE / 32));
2664 for _ in 0..counterparty_hash_commitment_number_len {
2665 let payment_hash: PaymentHash = Readable::read(reader)?;
2666 let commitment_number = <U48 as Readable>::read(reader)?.0;
2667 if let Some(_) = counterparty_hash_commitment_number.insert(payment_hash, commitment_number) {
2668 return Err(DecodeError::InvalidValue);
2672 let prev_holder_signed_commitment_tx = match <u8 as Readable>::read(reader)? {
2675 Some(Readable::read(reader)?)
2677 _ => return Err(DecodeError::InvalidValue),
2679 let current_holder_commitment_tx = Readable::read(reader)?;
2681 let current_counterparty_commitment_number = <U48 as Readable>::read(reader)?.0;
2682 let current_holder_commitment_number = <U48 as Readable>::read(reader)?.0;
2684 let payment_preimages_len: u64 = Readable::read(reader)?;
2685 let mut payment_preimages = HashMap::with_capacity(cmp::min(payment_preimages_len as usize, MAX_ALLOC_SIZE / 32));
2686 for _ in 0..payment_preimages_len {
2687 let preimage: PaymentPreimage = Readable::read(reader)?;
2688 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
2689 if let Some(_) = payment_preimages.insert(hash, preimage) {
2690 return Err(DecodeError::InvalidValue);
2694 let pending_monitor_events_len: u64 = Readable::read(reader)?;
2695 let mut pending_monitor_events = Vec::with_capacity(cmp::min(pending_monitor_events_len as usize, MAX_ALLOC_SIZE / (32 + 8*3)));
2696 for _ in 0..pending_monitor_events_len {
2697 let ev = match <u8 as Readable>::read(reader)? {
2698 0 => MonitorEvent::HTLCEvent(Readable::read(reader)?),
2699 1 => MonitorEvent::CommitmentTxBroadcasted(funding_info.0),
2700 _ => return Err(DecodeError::InvalidValue)
2702 pending_monitor_events.push(ev);
2705 let pending_events_len: u64 = Readable::read(reader)?;
2706 let mut pending_events = Vec::with_capacity(cmp::min(pending_events_len as usize, MAX_ALLOC_SIZE / mem::size_of::<Event>()));
2707 for _ in 0..pending_events_len {
2708 if let Some(event) = MaybeReadable::read(reader)? {
2709 pending_events.push(event);
2713 let best_block = BestBlock::new(Readable::read(reader)?, Readable::read(reader)?);
2715 let waiting_threshold_conf_len: u64 = Readable::read(reader)?;
2716 let mut onchain_events_awaiting_threshold_conf = Vec::with_capacity(cmp::min(waiting_threshold_conf_len as usize, MAX_ALLOC_SIZE / 128));
2717 for _ in 0..waiting_threshold_conf_len {
2718 onchain_events_awaiting_threshold_conf.push(Readable::read(reader)?);
2721 let outputs_to_watch_len: u64 = Readable::read(reader)?;
2722 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>>())));
2723 for _ in 0..outputs_to_watch_len {
2724 let txid = Readable::read(reader)?;
2725 let outputs_len: u64 = Readable::read(reader)?;
2726 let mut outputs = Vec::with_capacity(cmp::min(outputs_len as usize, MAX_ALLOC_SIZE / (mem::size_of::<u32>() + mem::size_of::<Script>())));
2727 for _ in 0..outputs_len {
2728 outputs.push((Readable::read(reader)?, Readable::read(reader)?));
2730 if let Some(_) = outputs_to_watch.insert(txid, outputs) {
2731 return Err(DecodeError::InvalidValue);
2734 let onchain_tx_handler = ReadableArgs::read(reader, keys_manager)?;
2736 let lockdown_from_offchain = Readable::read(reader)?;
2737 let holder_tx_signed = Readable::read(reader)?;
2739 read_tlv_fields!(reader, {});
2741 let mut secp_ctx = Secp256k1::new();
2742 secp_ctx.seeded_randomize(&keys_manager.get_secure_random_bytes());
2744 Ok((best_block.block_hash(), ChannelMonitor {
2745 inner: Mutex::new(ChannelMonitorImpl {
2747 commitment_transaction_number_obscure_factor,
2750 broadcasted_holder_revokable_script,
2751 counterparty_payment_script,
2755 holder_revocation_basepoint,
2757 current_counterparty_commitment_txid,
2758 prev_counterparty_commitment_txid,
2760 counterparty_tx_cache,
2761 funding_redeemscript,
2762 channel_value_satoshis,
2763 their_cur_revocation_points,
2768 counterparty_claimable_outpoints,
2769 counterparty_commitment_txn_on_chain,
2770 counterparty_hash_commitment_number,
2772 prev_holder_signed_commitment_tx,
2773 current_holder_commitment_tx,
2774 current_counterparty_commitment_number,
2775 current_holder_commitment_number,
2778 pending_monitor_events,
2781 onchain_events_awaiting_threshold_conf,
2786 lockdown_from_offchain,
2799 use bitcoin::blockdata::script::{Script, Builder};
2800 use bitcoin::blockdata::opcodes;
2801 use bitcoin::blockdata::transaction::{Transaction, TxIn, TxOut, SigHashType};
2802 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
2803 use bitcoin::util::bip143;
2804 use bitcoin::hashes::Hash;
2805 use bitcoin::hashes::sha256::Hash as Sha256;
2806 use bitcoin::hashes::hex::FromHex;
2807 use bitcoin::hash_types::Txid;
2808 use bitcoin::network::constants::Network;
2810 use chain::BestBlock;
2811 use chain::channelmonitor::ChannelMonitor;
2812 use chain::package::{WEIGHT_OFFERED_HTLC, WEIGHT_RECEIVED_HTLC, WEIGHT_REVOKED_OFFERED_HTLC, WEIGHT_REVOKED_RECEIVED_HTLC, WEIGHT_REVOKED_OUTPUT};
2813 use chain::transaction::OutPoint;
2814 use ln::{PaymentPreimage, PaymentHash};
2816 use ln::chan_utils::{HTLCOutputInCommitment, ChannelPublicKeys, ChannelTransactionParameters, HolderCommitmentTransaction, CounterpartyChannelTransactionParameters};
2817 use util::test_utils::{TestLogger, TestBroadcaster, TestFeeEstimator};
2818 use bitcoin::secp256k1::key::{SecretKey,PublicKey};
2819 use bitcoin::secp256k1::Secp256k1;
2820 use sync::{Arc, Mutex};
2821 use chain::keysinterface::InMemorySigner;
2825 fn test_prune_preimages() {
2826 let secp_ctx = Secp256k1::new();
2827 let logger = Arc::new(TestLogger::new());
2828 let broadcaster = Arc::new(TestBroadcaster{txn_broadcasted: Mutex::new(Vec::new()), blocks: Arc::new(Mutex::new(Vec::new()))});
2829 let fee_estimator = Arc::new(TestFeeEstimator { sat_per_kw: Mutex::new(253) });
2831 let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
2832 let dummy_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
2834 let mut preimages = Vec::new();
2837 let preimage = PaymentPreimage([i; 32]);
2838 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
2839 preimages.push((preimage, hash));
2843 macro_rules! preimages_slice_to_htlc_outputs {
2844 ($preimages_slice: expr) => {
2846 let mut res = Vec::new();
2847 for (idx, preimage) in $preimages_slice.iter().enumerate() {
2848 res.push((HTLCOutputInCommitment {
2852 payment_hash: preimage.1.clone(),
2853 transaction_output_index: Some(idx as u32),
2860 macro_rules! preimages_to_holder_htlcs {
2861 ($preimages_slice: expr) => {
2863 let mut inp = preimages_slice_to_htlc_outputs!($preimages_slice);
2864 let res: Vec<_> = inp.drain(..).map(|e| { (e.0, None, e.1) }).collect();
2870 macro_rules! test_preimages_exist {
2871 ($preimages_slice: expr, $monitor: expr) => {
2872 for preimage in $preimages_slice {
2873 assert!($monitor.inner.lock().unwrap().payment_preimages.contains_key(&preimage.1));
2878 let keys = InMemorySigner::new(
2880 SecretKey::from_slice(&[41; 32]).unwrap(),
2881 SecretKey::from_slice(&[41; 32]).unwrap(),
2882 SecretKey::from_slice(&[41; 32]).unwrap(),
2883 SecretKey::from_slice(&[41; 32]).unwrap(),
2884 SecretKey::from_slice(&[41; 32]).unwrap(),
2890 let counterparty_pubkeys = ChannelPublicKeys {
2891 funding_pubkey: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[44; 32]).unwrap()),
2892 revocation_basepoint: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()),
2893 payment_point: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[46; 32]).unwrap()),
2894 delayed_payment_basepoint: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[47; 32]).unwrap()),
2895 htlc_basepoint: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[48; 32]).unwrap())
2897 let funding_outpoint = OutPoint { txid: Default::default(), index: u16::max_value() };
2898 let channel_parameters = ChannelTransactionParameters {
2899 holder_pubkeys: keys.holder_channel_pubkeys.clone(),
2900 holder_selected_contest_delay: 66,
2901 is_outbound_from_holder: true,
2902 counterparty_parameters: Some(CounterpartyChannelTransactionParameters {
2903 pubkeys: counterparty_pubkeys,
2904 selected_contest_delay: 67,
2906 funding_outpoint: Some(funding_outpoint),
2908 // Prune with one old state and a holder commitment tx holding a few overlaps with the
2910 let best_block = BestBlock::from_genesis(Network::Testnet);
2911 let monitor = ChannelMonitor::new(Secp256k1::new(), keys,
2912 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap()), 0, &Script::new(),
2913 (OutPoint { txid: Txid::from_slice(&[43; 32]).unwrap(), index: 0 }, Script::new()),
2914 &channel_parameters,
2915 Script::new(), 46, 0,
2916 HolderCommitmentTransaction::dummy(), best_block);
2918 monitor.provide_latest_holder_commitment_tx(HolderCommitmentTransaction::dummy(), preimages_to_holder_htlcs!(preimages[0..10])).unwrap();
2919 let dummy_txid = dummy_tx.txid();
2920 monitor.provide_latest_counterparty_commitment_tx(dummy_txid, preimages_slice_to_htlc_outputs!(preimages[5..15]), 281474976710655, dummy_key, &logger);
2921 monitor.provide_latest_counterparty_commitment_tx(dummy_txid, preimages_slice_to_htlc_outputs!(preimages[15..20]), 281474976710654, dummy_key, &logger);
2922 monitor.provide_latest_counterparty_commitment_tx(dummy_txid, preimages_slice_to_htlc_outputs!(preimages[17..20]), 281474976710653, dummy_key, &logger);
2923 monitor.provide_latest_counterparty_commitment_tx(dummy_txid, preimages_slice_to_htlc_outputs!(preimages[18..20]), 281474976710652, dummy_key, &logger);
2924 for &(ref preimage, ref hash) in preimages.iter() {
2925 monitor.provide_payment_preimage(hash, preimage, &broadcaster, &fee_estimator, &logger);
2928 // Now provide a secret, pruning preimages 10-15
2929 let mut secret = [0; 32];
2930 secret[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2931 monitor.provide_secret(281474976710655, secret.clone()).unwrap();
2932 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 15);
2933 test_preimages_exist!(&preimages[0..10], monitor);
2934 test_preimages_exist!(&preimages[15..20], monitor);
2936 // Now provide a further secret, pruning preimages 15-17
2937 secret[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2938 monitor.provide_secret(281474976710654, secret.clone()).unwrap();
2939 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 13);
2940 test_preimages_exist!(&preimages[0..10], monitor);
2941 test_preimages_exist!(&preimages[17..20], monitor);
2943 // Now update holder commitment tx info, pruning only element 18 as we still care about the
2944 // previous commitment tx's preimages too
2945 monitor.provide_latest_holder_commitment_tx(HolderCommitmentTransaction::dummy(), preimages_to_holder_htlcs!(preimages[0..5])).unwrap();
2946 secret[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2947 monitor.provide_secret(281474976710653, secret.clone()).unwrap();
2948 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 12);
2949 test_preimages_exist!(&preimages[0..10], monitor);
2950 test_preimages_exist!(&preimages[18..20], monitor);
2952 // But if we do it again, we'll prune 5-10
2953 monitor.provide_latest_holder_commitment_tx(HolderCommitmentTransaction::dummy(), preimages_to_holder_htlcs!(preimages[0..3])).unwrap();
2954 secret[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2955 monitor.provide_secret(281474976710652, secret.clone()).unwrap();
2956 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 5);
2957 test_preimages_exist!(&preimages[0..5], monitor);
2961 fn test_claim_txn_weight_computation() {
2962 // We test Claim txn weight, knowing that we want expected weigth and
2963 // not actual case to avoid sigs and time-lock delays hell variances.
2965 let secp_ctx = Secp256k1::new();
2966 let privkey = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
2967 let pubkey = PublicKey::from_secret_key(&secp_ctx, &privkey);
2968 let mut sum_actual_sigs = 0;
2970 macro_rules! sign_input {
2971 ($sighash_parts: expr, $idx: expr, $amount: expr, $weight: expr, $sum_actual_sigs: expr) => {
2972 let htlc = HTLCOutputInCommitment {
2973 offered: if *$weight == WEIGHT_REVOKED_OFFERED_HTLC || *$weight == WEIGHT_OFFERED_HTLC { true } else { false },
2975 cltv_expiry: 2 << 16,
2976 payment_hash: PaymentHash([1; 32]),
2977 transaction_output_index: Some($idx as u32),
2979 let redeem_script = if *$weight == WEIGHT_REVOKED_OUTPUT { chan_utils::get_revokeable_redeemscript(&pubkey, 256, &pubkey) } else { chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &pubkey, &pubkey, &pubkey) };
2980 let sighash = hash_to_message!(&$sighash_parts.signature_hash($idx, &redeem_script, $amount, SigHashType::All)[..]);
2981 let sig = secp_ctx.sign(&sighash, &privkey);
2982 $sighash_parts.access_witness($idx).push(sig.serialize_der().to_vec());
2983 $sighash_parts.access_witness($idx)[0].push(SigHashType::All as u8);
2984 sum_actual_sigs += $sighash_parts.access_witness($idx)[0].len();
2985 if *$weight == WEIGHT_REVOKED_OUTPUT {
2986 $sighash_parts.access_witness($idx).push(vec!(1));
2987 } else if *$weight == WEIGHT_REVOKED_OFFERED_HTLC || *$weight == WEIGHT_REVOKED_RECEIVED_HTLC {
2988 $sighash_parts.access_witness($idx).push(pubkey.clone().serialize().to_vec());
2989 } else if *$weight == WEIGHT_RECEIVED_HTLC {
2990 $sighash_parts.access_witness($idx).push(vec![0]);
2992 $sighash_parts.access_witness($idx).push(PaymentPreimage([1; 32]).0.to_vec());
2994 $sighash_parts.access_witness($idx).push(redeem_script.into_bytes());
2995 println!("witness[0] {}", $sighash_parts.access_witness($idx)[0].len());
2996 println!("witness[1] {}", $sighash_parts.access_witness($idx)[1].len());
2997 println!("witness[2] {}", $sighash_parts.access_witness($idx)[2].len());
3001 let script_pubkey = Builder::new().push_opcode(opcodes::all::OP_RETURN).into_script();
3002 let txid = Txid::from_hex("56944c5d3f98413ef45cf54545538103cc9f298e0575820ad3591376e2e0f65d").unwrap();
3004 // Justice tx with 1 to_holder, 2 revoked offered HTLCs, 1 revoked received HTLCs
3005 let mut claim_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
3007 claim_tx.input.push(TxIn {
3008 previous_output: BitcoinOutPoint {
3012 script_sig: Script::new(),
3013 sequence: 0xfffffffd,
3014 witness: Vec::new(),
3017 claim_tx.output.push(TxOut {
3018 script_pubkey: script_pubkey.clone(),
3021 let base_weight = claim_tx.get_weight();
3022 let inputs_weight = vec![WEIGHT_REVOKED_OUTPUT, WEIGHT_REVOKED_OFFERED_HTLC, WEIGHT_REVOKED_OFFERED_HTLC, WEIGHT_REVOKED_RECEIVED_HTLC];
3023 let mut inputs_total_weight = 2; // count segwit flags
3025 let mut sighash_parts = bip143::SigHashCache::new(&mut claim_tx);
3026 for (idx, inp) in inputs_weight.iter().enumerate() {
3027 sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs);
3028 inputs_total_weight += inp;
3031 assert_eq!(base_weight + inputs_total_weight as usize, claim_tx.get_weight() + /* max_length_sig */ (73 * inputs_weight.len() - sum_actual_sigs));
3033 // Claim tx with 1 offered HTLCs, 3 received HTLCs
3034 claim_tx.input.clear();
3035 sum_actual_sigs = 0;
3037 claim_tx.input.push(TxIn {
3038 previous_output: BitcoinOutPoint {
3042 script_sig: Script::new(),
3043 sequence: 0xfffffffd,
3044 witness: Vec::new(),
3047 let base_weight = claim_tx.get_weight();
3048 let inputs_weight = vec![WEIGHT_OFFERED_HTLC, WEIGHT_RECEIVED_HTLC, WEIGHT_RECEIVED_HTLC, WEIGHT_RECEIVED_HTLC];
3049 let mut inputs_total_weight = 2; // count segwit flags
3051 let mut sighash_parts = bip143::SigHashCache::new(&mut claim_tx);
3052 for (idx, inp) in inputs_weight.iter().enumerate() {
3053 sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs);
3054 inputs_total_weight += inp;
3057 assert_eq!(base_weight + inputs_total_weight as usize, claim_tx.get_weight() + /* max_length_sig */ (73 * inputs_weight.len() - sum_actual_sigs));
3059 // Justice tx with 1 revoked HTLC-Success tx output
3060 claim_tx.input.clear();
3061 sum_actual_sigs = 0;
3062 claim_tx.input.push(TxIn {
3063 previous_output: BitcoinOutPoint {
3067 script_sig: Script::new(),
3068 sequence: 0xfffffffd,
3069 witness: Vec::new(),
3071 let base_weight = claim_tx.get_weight();
3072 let inputs_weight = vec![WEIGHT_REVOKED_OUTPUT];
3073 let mut inputs_total_weight = 2; // count segwit flags
3075 let mut sighash_parts = bip143::SigHashCache::new(&mut claim_tx);
3076 for (idx, inp) in inputs_weight.iter().enumerate() {
3077 sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs);
3078 inputs_total_weight += inp;
3081 assert_eq!(base_weight + inputs_total_weight as usize, claim_tx.get_weight() + /* max_length_isg */ (73 * inputs_weight.len() - sum_actual_sigs));
3084 // Further testing is done in the ChannelManager integration tests.