1 // This file is Copyright its original authors, visible in version control
4 // This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
5 // or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
6 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
7 // You may not use this file except in accordance with one or both of these
10 //! The logic to monitor for on-chain transactions and create the relevant claim responses lives
13 //! ChannelMonitor objects are generated by ChannelManager in response to relevant
14 //! messages/actions, and MUST be persisted to disk (and, preferably, remotely) before progress can
15 //! be made in responding to certain messages, see [`chain::Watch`] for more.
17 //! Note that ChannelMonitors are an important part of the lightning trust model and a copy of the
18 //! latest ChannelMonitor must always be actively monitoring for chain updates (and no out-of-date
19 //! ChannelMonitors should do so). Thus, if you're building rust-lightning into an HSM or other
20 //! security-domain-separated system design, you should consider having multiple paths for
21 //! ChannelMonitors to get out of the HSM and onto monitoring devices.
23 use bitcoin::blockdata::block::{Block, BlockHeader};
24 use bitcoin::blockdata::transaction::{TxOut,Transaction};
25 use bitcoin::blockdata::script::{Script, Builder};
26 use bitcoin::blockdata::opcodes;
28 use bitcoin::hashes::Hash;
29 use bitcoin::hashes::sha256::Hash as Sha256;
30 use bitcoin::hash_types::{Txid, BlockHash, WPubkeyHash};
32 use bitcoin::secp256k1::{Secp256k1,Signature};
33 use bitcoin::secp256k1::key::{SecretKey,PublicKey};
34 use bitcoin::secp256k1;
36 use ln::{PaymentHash, PaymentPreimage};
37 use ln::msgs::DecodeError;
39 use ln::chan_utils::{CounterpartyCommitmentSecrets, HTLCOutputInCommitment, HTLCType, ChannelTransactionParameters, HolderCommitmentTransaction};
40 use ln::channelmanager::{BestBlock, HTLCSource};
42 use chain::WatchedOutput;
43 use chain::chaininterface::{BroadcasterInterface, FeeEstimator};
44 use chain::transaction::{OutPoint, TransactionData};
45 use chain::keysinterface::{SpendableOutputDescriptor, StaticPaymentOutputDescriptor, DelayedPaymentOutputDescriptor, Sign, KeysInterface};
46 use chain::onchaintx::OnchainTxHandler;
47 use chain::package::{CounterpartyOfferedHTLCOutput, CounterpartyReceivedHTLCOutput, HolderFundingOutput, HolderHTLCOutput, PackageSolvingData, PackageTemplate, RevokedOutput, RevokedHTLCOutput};
49 use util::logger::Logger;
50 use util::ser::{Readable, ReadableArgs, MaybeReadable, Writer, Writeable, U48};
52 use util::events::Event;
55 use std::collections::{HashMap, HashSet};
61 /// An update generated by the underlying Channel itself which contains some new information the
62 /// ChannelMonitor should be made aware of.
63 #[cfg_attr(any(test, feature = "fuzztarget", feature = "_test_utils"), derive(PartialEq))]
66 pub struct ChannelMonitorUpdate {
67 pub(crate) updates: Vec<ChannelMonitorUpdateStep>,
68 /// The sequence number of this update. Updates *must* be replayed in-order according to this
69 /// sequence number (and updates may panic if they are not). The update_id values are strictly
70 /// increasing and increase by one for each new update, with one exception specified below.
72 /// This sequence number is also used to track up to which points updates which returned
73 /// ChannelMonitorUpdateErr::TemporaryFailure have been applied to all copies of a given
74 /// ChannelMonitor when ChannelManager::channel_monitor_updated is called.
76 /// The only instance where update_id values are not strictly increasing is the case where we
77 /// allow post-force-close updates with a special update ID of [`CLOSED_CHANNEL_UPDATE_ID`]. See
78 /// its docs for more details.
83 /// (1) a channel has been force closed and
84 /// (2) we receive a preimage from a forward link that allows us to spend an HTLC output on
85 /// this channel's (the backward link's) broadcasted commitment transaction
86 /// then we allow the `ChannelManager` to send a `ChannelMonitorUpdate` with this update ID,
87 /// with the update providing said payment preimage. No other update types are allowed after
89 pub const CLOSED_CHANNEL_UPDATE_ID: u64 = core::u64::MAX;
91 impl Writeable for ChannelMonitorUpdate {
92 fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
93 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)?;
101 impl Readable for ChannelMonitorUpdate {
102 fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
103 let update_id: u64 = Readable::read(r)?;
104 let len: u64 = Readable::read(r)?;
105 let mut updates = Vec::with_capacity(cmp::min(len as usize, MAX_ALLOC_SIZE / ::core::mem::size_of::<ChannelMonitorUpdateStep>()));
107 updates.push(Readable::read(r)?);
109 Ok(Self { update_id, updates })
113 /// An error enum representing a failure to persist a channel monitor update.
114 #[derive(Clone, Debug)]
115 pub enum ChannelMonitorUpdateErr {
116 /// Used to indicate a temporary failure (eg connection to a watchtower or remote backup of
117 /// our state failed, but is expected to succeed at some point in the future).
119 /// Such a failure will "freeze" a channel, preventing us from revoking old states or
120 /// submitting new commitment transactions to the counterparty. Once the update(s) which failed
121 /// have been successfully applied, ChannelManager::channel_monitor_updated can be used to
122 /// restore the channel to an operational state.
124 /// Note that a given ChannelManager will *never* re-generate a given ChannelMonitorUpdate. If
125 /// you return a TemporaryFailure you must ensure that it is written to disk safely before
126 /// writing out the latest ChannelManager state.
128 /// Even when a channel has been "frozen" updates to the ChannelMonitor can continue to occur
129 /// (eg if an inbound HTLC which we forwarded was claimed upstream resulting in us attempting
130 /// to claim it on this channel) and those updates must be applied wherever they can be. At
131 /// least one such updated ChannelMonitor must be persisted otherwise PermanentFailure should
132 /// be returned to get things on-chain ASAP using only the in-memory copy. Obviously updates to
133 /// the channel which would invalidate previous ChannelMonitors are not made when a channel has
136 /// Note that even if updates made after TemporaryFailure succeed you must still call
137 /// channel_monitor_updated to ensure you have the latest monitor and re-enable normal channel
140 /// Note that the update being processed here will not be replayed for you when you call
141 /// ChannelManager::channel_monitor_updated, so you must store the update itself along
142 /// with the persisted ChannelMonitor on your own local disk prior to returning a
143 /// TemporaryFailure. You may, of course, employ a journaling approach, storing only the
144 /// ChannelMonitorUpdate on disk without updating the monitor itself, replaying the journal at
147 /// For deployments where a copy of ChannelMonitors and other local state are backed up in a
148 /// remote location (with local copies persisted immediately), it is anticipated that all
149 /// updates will return TemporaryFailure until the remote copies could be updated.
151 /// Used to indicate no further channel monitor updates will be allowed (eg we've moved on to a
152 /// different watchtower and cannot update with all watchtowers that were previously informed
153 /// of this channel).
155 /// At reception of this error, ChannelManager will force-close the channel and return at
156 /// least a final ChannelMonitorUpdate::ChannelForceClosed which must be delivered to at
157 /// least one ChannelMonitor copy. Revocation secret MUST NOT be released and offchain channel
158 /// update must be rejected.
160 /// This failure may also signal a failure to update the local persisted copy of one of
161 /// the channel monitor instance.
163 /// Note that even when you fail a holder commitment transaction update, you must store the
164 /// update to ensure you can claim from it in case of a duplicate copy of this ChannelMonitor
165 /// broadcasts it (e.g distributed channel-monitor deployment)
167 /// In case of distributed watchtowers deployment, the new version must be written to disk, as
168 /// state may have been stored but rejected due to a block forcing a commitment broadcast. This
169 /// storage is used to claim outputs of rejected state confirmed onchain by another watchtower,
170 /// lagging behind on block processing.
174 /// General Err type for ChannelMonitor actions. Generally, this implies that the data provided is
175 /// inconsistent with the ChannelMonitor being called. eg for ChannelMonitor::update_monitor this
176 /// means you tried to update a monitor for a different channel or the ChannelMonitorUpdate was
178 /// Contains a developer-readable error message.
179 #[derive(Clone, Debug)]
180 pub struct MonitorUpdateError(pub &'static str);
182 /// An event to be processed by the ChannelManager.
183 #[derive(Clone, PartialEq)]
184 pub enum MonitorEvent {
185 /// A monitor event containing an HTLCUpdate.
186 HTLCEvent(HTLCUpdate),
188 /// A monitor event that the Channel's commitment transaction was broadcasted.
189 CommitmentTxBroadcasted(OutPoint),
192 /// Simple structure sent back by `chain::Watch` when an HTLC from a forward channel is detected on
193 /// chain. Used to update the corresponding HTLC in the backward channel. Failing to pass the
194 /// preimage claim backward will lead to loss of funds.
195 #[derive(Clone, PartialEq)]
196 pub struct HTLCUpdate {
197 pub(crate) payment_hash: PaymentHash,
198 pub(crate) payment_preimage: Option<PaymentPreimage>,
199 pub(crate) source: HTLCSource
201 impl_writeable_tlv_based!(HTLCUpdate, {
205 (4, payment_preimage)
208 /// If an HTLC expires within this many blocks, don't try to claim it in a shared transaction,
209 /// instead claiming it in its own individual transaction.
210 pub(crate) const CLTV_SHARED_CLAIM_BUFFER: u32 = 12;
211 /// If an HTLC expires within this many blocks, force-close the channel to broadcast the
212 /// HTLC-Success transaction.
213 /// In other words, this is an upper bound on how many blocks we think it can take us to get a
214 /// transaction confirmed (and we use it in a few more, equivalent, places).
215 pub(crate) const CLTV_CLAIM_BUFFER: u32 = 18;
216 /// Number of blocks by which point we expect our counterparty to have seen new blocks on the
217 /// network and done a full update_fail_htlc/commitment_signed dance (+ we've updated all our
218 /// copies of ChannelMonitors, including watchtowers). We could enforce the contract by failing
219 /// at CLTV expiration height but giving a grace period to our peer may be profitable for us if he
220 /// can provide an over-late preimage. Nevertheless, grace period has to be accounted in our
221 /// CLTV_EXPIRY_DELTA to be secure. Following this policy we may decrease the rate of channel failures
222 /// due to expiration but increase the cost of funds being locked longuer in case of failure.
223 /// This delay also cover a low-power peer being slow to process blocks and so being behind us on
224 /// accurate block height.
225 /// In case of onchain failure to be pass backward we may see the last block of ANTI_REORG_DELAY
226 /// with at worst this delay, so we are not only using this value as a mercy for them but also
227 /// us as a safeguard to delay with enough time.
228 pub(crate) const LATENCY_GRACE_PERIOD_BLOCKS: u32 = 3;
229 /// Number of blocks we wait on seeing a HTLC output being solved before we fail corresponding inbound
230 /// HTLCs. This prevents us from failing backwards and then getting a reorg resulting in us losing money.
231 // We also use this delay to be sure we can remove our in-flight claim txn from bump candidates buffer.
232 // It may cause spurious generation of bumped claim txn but that's alright given the outpoint is already
233 // solved by a previous claim tx. What we want to avoid is reorg evicting our claim tx and us not
234 // keep bumping another claim tx to solve the outpoint.
235 pub const ANTI_REORG_DELAY: u32 = 6;
236 /// Number of blocks before confirmation at which we fail back an un-relayed HTLC or at which we
237 /// refuse to accept a new HTLC.
239 /// This is used for a few separate purposes:
240 /// 1) if we've received an MPP HTLC to us and it expires within this many blocks and we are
241 /// waiting on additional parts (or waiting on the preimage for any HTLC from the user), we will
243 /// 2) if we receive an HTLC within this many blocks of its expiry (plus one to avoid a race
244 /// condition with the above), we will fail this HTLC without telling the user we received it,
245 /// 3) if we are waiting on a connection or a channel state update to send an HTLC to a peer, and
246 /// that HTLC expires within this many blocks, we will simply fail the HTLC instead.
248 /// (1) is all about protecting us - we need enough time to update the channel state before we hit
249 /// CLTV_CLAIM_BUFFER, at which point we'd go on chain to claim the HTLC with the preimage.
251 /// (2) is the same, but with an additional buffer to avoid accepting an HTLC which is immediately
252 /// in a race condition between the user connecting a block (which would fail it) and the user
253 /// providing us the preimage (which would claim it).
255 /// (3) is about our counterparty - we don't want to relay an HTLC to a counterparty when they may
256 /// end up force-closing the channel on us to claim it.
257 pub(crate) const HTLC_FAIL_BACK_BUFFER: u32 = CLTV_CLAIM_BUFFER + LATENCY_GRACE_PERIOD_BLOCKS;
259 // TODO(devrandom) replace this with HolderCommitmentTransaction
260 #[derive(Clone, PartialEq)]
261 struct HolderSignedTx {
262 /// txid of the transaction in tx, just used to make comparison faster
264 revocation_key: PublicKey,
265 a_htlc_key: PublicKey,
266 b_htlc_key: PublicKey,
267 delayed_payment_key: PublicKey,
268 per_commitment_point: PublicKey,
270 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
272 impl_writeable_tlv_based!(HolderSignedTx, {
277 (8, delayed_payment_key),
278 (10, per_commitment_point),
279 (12, feerate_per_kw),
284 /// We use this to track counterparty commitment transactions and htlcs outputs and
285 /// use it to generate any justice or 2nd-stage preimage/timeout transactions.
287 struct CounterpartyCommitmentTransaction {
288 counterparty_delayed_payment_base_key: PublicKey,
289 counterparty_htlc_base_key: PublicKey,
290 on_counterparty_tx_csv: u16,
291 per_htlc: HashMap<Txid, Vec<HTLCOutputInCommitment>>
294 impl Writeable for CounterpartyCommitmentTransaction {
295 fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
296 self.counterparty_delayed_payment_base_key.write(w)?;
297 self.counterparty_htlc_base_key.write(w)?;
298 w.write_all(&byte_utils::be16_to_array(self.on_counterparty_tx_csv))?;
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() {
310 impl Readable for CounterpartyCommitmentTransaction {
311 fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
312 let counterparty_commitment_transaction = {
313 let counterparty_delayed_payment_base_key = Readable::read(r)?;
314 let counterparty_htlc_base_key = Readable::read(r)?;
315 let on_counterparty_tx_csv: u16 = Readable::read(r)?;
316 let per_htlc_len: u64 = Readable::read(r)?;
317 let mut per_htlc = HashMap::with_capacity(cmp::min(per_htlc_len as usize, MAX_ALLOC_SIZE / 64));
318 for _ in 0..per_htlc_len {
319 let txid: Txid = Readable::read(r)?;
320 let htlcs_count: u64 = Readable::read(r)?;
321 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
322 for _ in 0..htlcs_count {
323 let htlc = Readable::read(r)?;
326 if let Some(_) = per_htlc.insert(txid, htlcs) {
327 return Err(DecodeError::InvalidValue);
330 CounterpartyCommitmentTransaction {
331 counterparty_delayed_payment_base_key,
332 counterparty_htlc_base_key,
333 on_counterparty_tx_csv,
337 Ok(counterparty_commitment_transaction)
341 /// An entry for an [`OnchainEvent`], stating the block height when the event was observed and the
342 /// transaction causing it.
344 /// Used to determine when the on-chain event can be considered safe from a chain reorganization.
346 struct OnchainEventEntry {
352 impl OnchainEventEntry {
353 fn confirmation_threshold(&self) -> u32 {
354 self.height + ANTI_REORG_DELAY - 1
357 fn has_reached_confirmation_threshold(&self, height: u32) -> bool {
358 height >= self.confirmation_threshold()
362 /// Upon discovering of some classes of onchain tx by ChannelMonitor, we may have to take actions on it
363 /// once they mature to enough confirmations (ANTI_REORG_DELAY)
366 /// HTLC output getting solved by a timeout, at maturation we pass upstream payment source information to solve
367 /// inbound HTLC in backward channel. Note, in case of preimage, we pass info to upstream without delay as we can
368 /// only win from it, so it's never an OnchainEvent
371 payment_hash: PaymentHash,
374 descriptor: SpendableOutputDescriptor,
378 impl_writeable_tlv_based!(OnchainEventEntry, {
384 impl_writeable_tlv_based_enum!(OnchainEvent,
389 (1, MaturingOutput) => {
394 #[cfg_attr(any(test, feature = "fuzztarget", feature = "_test_utils"), derive(PartialEq))]
396 pub(crate) enum ChannelMonitorUpdateStep {
397 LatestHolderCommitmentTXInfo {
398 commitment_tx: HolderCommitmentTransaction,
399 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
401 LatestCounterpartyCommitmentTXInfo {
402 commitment_txid: Txid,
403 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
404 commitment_number: u64,
405 their_revocation_point: PublicKey,
408 payment_preimage: PaymentPreimage,
414 /// Used to indicate that the no future updates will occur, and likely that the latest holder
415 /// commitment transaction(s) should be broadcast, as the channel has been force-closed.
417 /// If set to false, we shouldn't broadcast the latest holder commitment transaction as we
418 /// think we've fallen behind!
419 should_broadcast: bool,
423 impl_writeable_tlv_based_enum!(ChannelMonitorUpdateStep,
424 (0, LatestHolderCommitmentTXInfo) => {
429 (1, LatestCounterpartyCommitmentTXInfo) => {
430 (0, commitment_txid),
431 (2, commitment_number),
432 (4, their_revocation_point),
436 (2, PaymentPreimage) => {
437 (0, payment_preimage),
439 (3, CommitmentSecret) => {
443 (4, ChannelForceClosed) => {
444 (0, should_broadcast),
448 /// A ChannelMonitor handles chain events (blocks connected and disconnected) and generates
449 /// on-chain transactions to ensure no loss of funds occurs.
451 /// You MUST ensure that no ChannelMonitors for a given channel anywhere contain out-of-date
452 /// information and are actively monitoring the chain.
454 /// Pending Events or updated HTLCs which have not yet been read out by
455 /// get_and_clear_pending_monitor_events or get_and_clear_pending_events are serialized to disk and
456 /// reloaded at deserialize-time. Thus, you must ensure that, when handling events, all events
457 /// gotten are fully handled before re-serializing the new state.
459 /// Note that the deserializer is only implemented for (BlockHash, ChannelMonitor), which
460 /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
461 /// the "reorg path" (ie disconnecting blocks until you find a common ancestor from both the
462 /// returned block hash and the the current chain and then reconnecting blocks to get to the
463 /// best chain) upon deserializing the object!
464 pub struct ChannelMonitor<Signer: Sign> {
466 pub(crate) inner: Mutex<ChannelMonitorImpl<Signer>>,
468 inner: Mutex<ChannelMonitorImpl<Signer>>,
471 pub(crate) struct ChannelMonitorImpl<Signer: Sign> {
472 latest_update_id: u64,
473 commitment_transaction_number_obscure_factor: u64,
475 destination_script: Script,
476 broadcasted_holder_revokable_script: Option<(Script, PublicKey, PublicKey)>,
477 counterparty_payment_script: Script,
478 shutdown_script: Script,
480 channel_keys_id: [u8; 32],
481 holder_revocation_basepoint: PublicKey,
482 funding_info: (OutPoint, Script),
483 current_counterparty_commitment_txid: Option<Txid>,
484 prev_counterparty_commitment_txid: Option<Txid>,
486 counterparty_tx_cache: CounterpartyCommitmentTransaction,
487 funding_redeemscript: Script,
488 channel_value_satoshis: u64,
489 // first is the idx of the first of the two revocation points
490 their_cur_revocation_points: Option<(u64, PublicKey, Option<PublicKey>)>,
492 on_holder_tx_csv: u16,
494 commitment_secrets: CounterpartyCommitmentSecrets,
495 counterparty_claimable_outpoints: HashMap<Txid, Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>>,
496 /// We cannot identify HTLC-Success or HTLC-Timeout transactions by themselves on the chain.
497 /// Nor can we figure out their commitment numbers without the commitment transaction they are
498 /// spending. Thus, in order to claim them via revocation key, we track all the counterparty
499 /// commitment transactions which we find on-chain, mapping them to the commitment number which
500 /// can be used to derive the revocation key and claim the transactions.
501 counterparty_commitment_txn_on_chain: HashMap<Txid, u64>,
502 /// Cache used to make pruning of payment_preimages faster.
503 /// Maps payment_hash values to commitment numbers for counterparty transactions for non-revoked
504 /// counterparty transactions (ie should remain pretty small).
505 /// Serialized to disk but should generally not be sent to Watchtowers.
506 counterparty_hash_commitment_number: HashMap<PaymentHash, u64>,
508 // We store two holder commitment transactions to avoid any race conditions where we may update
509 // some monitors (potentially on watchtowers) but then fail to update others, resulting in the
510 // various monitors for one channel being out of sync, and us broadcasting a holder
511 // transaction for which we have deleted claim information on some watchtowers.
512 prev_holder_signed_commitment_tx: Option<HolderSignedTx>,
513 current_holder_commitment_tx: HolderSignedTx,
515 // Used just for ChannelManager to make sure it has the latest channel data during
517 current_counterparty_commitment_number: u64,
518 // Used just for ChannelManager to make sure it has the latest channel data during
520 current_holder_commitment_number: u64,
522 payment_preimages: HashMap<PaymentHash, PaymentPreimage>,
524 pending_monitor_events: Vec<MonitorEvent>,
525 pending_events: Vec<Event>,
527 // Used to track on-chain events (i.e., transactions part of channels confirmed on chain) on
528 // which to take actions once they reach enough confirmations. Each entry includes the
529 // transaction's id and the height when the transaction was confirmed on chain.
530 onchain_events_awaiting_threshold_conf: Vec<OnchainEventEntry>,
532 // If we get serialized out and re-read, we need to make sure that the chain monitoring
533 // interface knows about the TXOs that we want to be notified of spends of. We could probably
534 // be smart and derive them from the above storage fields, but its much simpler and more
535 // Obviously Correct (tm) if we just keep track of them explicitly.
536 outputs_to_watch: HashMap<Txid, Vec<(u32, Script)>>,
539 pub onchain_tx_handler: OnchainTxHandler<Signer>,
541 onchain_tx_handler: OnchainTxHandler<Signer>,
543 // This is set when the Channel[Manager] generated a ChannelMonitorUpdate which indicated the
544 // channel has been force-closed. After this is set, no further holder commitment transaction
545 // updates may occur, and we panic!() if one is provided.
546 lockdown_from_offchain: bool,
548 // Set once we've signed a holder commitment transaction and handed it over to our
549 // OnchainTxHandler. After this is set, no future updates to our holder commitment transactions
550 // may occur, and we fail any such monitor updates.
552 // In case of update rejection due to a locally already signed commitment transaction, we
553 // nevertheless store update content to track in case of concurrent broadcast by another
554 // remote monitor out-of-order with regards to the block view.
555 holder_tx_signed: bool,
557 // We simply modify best_block in Channel's block_connected so that serialization is
558 // consistent but hopefully the users' copy handles block_connected in a consistent way.
559 // (we do *not*, however, update them in update_monitor to ensure any local user copies keep
560 // their best_block from its state and not based on updated copies that didn't run through
561 // the full block_connected).
562 best_block: BestBlock,
564 secp_ctx: Secp256k1<secp256k1::All>, //TODO: dedup this a bit...
567 /// Transaction outputs to watch for on-chain spends.
568 pub type TransactionOutputs = (Txid, Vec<(u32, TxOut)>);
570 #[cfg(any(test, feature = "fuzztarget", feature = "_test_utils"))]
571 /// Used only in testing and fuzztarget to check serialization roundtrips don't change the
572 /// underlying object
573 impl<Signer: Sign> PartialEq for ChannelMonitor<Signer> {
574 fn eq(&self, other: &Self) -> bool {
575 let inner = self.inner.lock().unwrap();
576 let other = other.inner.lock().unwrap();
581 #[cfg(any(test, feature = "fuzztarget", feature = "_test_utils"))]
582 /// Used only in testing and fuzztarget to check serialization roundtrips don't change the
583 /// underlying object
584 impl<Signer: Sign> PartialEq for ChannelMonitorImpl<Signer> {
585 fn eq(&self, other: &Self) -> bool {
586 if self.latest_update_id != other.latest_update_id ||
587 self.commitment_transaction_number_obscure_factor != other.commitment_transaction_number_obscure_factor ||
588 self.destination_script != other.destination_script ||
589 self.broadcasted_holder_revokable_script != other.broadcasted_holder_revokable_script ||
590 self.counterparty_payment_script != other.counterparty_payment_script ||
591 self.channel_keys_id != other.channel_keys_id ||
592 self.holder_revocation_basepoint != other.holder_revocation_basepoint ||
593 self.funding_info != other.funding_info ||
594 self.current_counterparty_commitment_txid != other.current_counterparty_commitment_txid ||
595 self.prev_counterparty_commitment_txid != other.prev_counterparty_commitment_txid ||
596 self.counterparty_tx_cache != other.counterparty_tx_cache ||
597 self.funding_redeemscript != other.funding_redeemscript ||
598 self.channel_value_satoshis != other.channel_value_satoshis ||
599 self.their_cur_revocation_points != other.their_cur_revocation_points ||
600 self.on_holder_tx_csv != other.on_holder_tx_csv ||
601 self.commitment_secrets != other.commitment_secrets ||
602 self.counterparty_claimable_outpoints != other.counterparty_claimable_outpoints ||
603 self.counterparty_commitment_txn_on_chain != other.counterparty_commitment_txn_on_chain ||
604 self.counterparty_hash_commitment_number != other.counterparty_hash_commitment_number ||
605 self.prev_holder_signed_commitment_tx != other.prev_holder_signed_commitment_tx ||
606 self.current_counterparty_commitment_number != other.current_counterparty_commitment_number ||
607 self.current_holder_commitment_number != other.current_holder_commitment_number ||
608 self.current_holder_commitment_tx != other.current_holder_commitment_tx ||
609 self.payment_preimages != other.payment_preimages ||
610 self.pending_monitor_events != other.pending_monitor_events ||
611 self.pending_events.len() != other.pending_events.len() || // We trust events to round-trip properly
612 self.onchain_events_awaiting_threshold_conf != other.onchain_events_awaiting_threshold_conf ||
613 self.outputs_to_watch != other.outputs_to_watch ||
614 self.lockdown_from_offchain != other.lockdown_from_offchain ||
615 self.holder_tx_signed != other.holder_tx_signed
624 impl<Signer: Sign> Writeable for ChannelMonitor<Signer> {
625 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), Error> {
626 self.inner.lock().unwrap().write(writer)
630 const SERIALIZATION_VERSION: u8 = 1;
631 const MIN_SERIALIZATION_VERSION: u8 = 1;
633 impl<Signer: Sign> Writeable for ChannelMonitorImpl<Signer> {
634 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), Error> {
635 write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
637 self.latest_update_id.write(writer)?;
639 // Set in initial Channel-object creation, so should always be set by now:
640 U48(self.commitment_transaction_number_obscure_factor).write(writer)?;
642 self.destination_script.write(writer)?;
643 if let Some(ref broadcasted_holder_revokable_script) = self.broadcasted_holder_revokable_script {
644 writer.write_all(&[0; 1])?;
645 broadcasted_holder_revokable_script.0.write(writer)?;
646 broadcasted_holder_revokable_script.1.write(writer)?;
647 broadcasted_holder_revokable_script.2.write(writer)?;
649 writer.write_all(&[1; 1])?;
652 self.counterparty_payment_script.write(writer)?;
653 self.shutdown_script.write(writer)?;
655 self.channel_keys_id.write(writer)?;
656 self.holder_revocation_basepoint.write(writer)?;
657 writer.write_all(&self.funding_info.0.txid[..])?;
658 writer.write_all(&byte_utils::be16_to_array(self.funding_info.0.index))?;
659 self.funding_info.1.write(writer)?;
660 self.current_counterparty_commitment_txid.write(writer)?;
661 self.prev_counterparty_commitment_txid.write(writer)?;
663 self.counterparty_tx_cache.write(writer)?;
664 self.funding_redeemscript.write(writer)?;
665 self.channel_value_satoshis.write(writer)?;
667 match self.their_cur_revocation_points {
668 Some((idx, pubkey, second_option)) => {
669 writer.write_all(&byte_utils::be48_to_array(idx))?;
670 writer.write_all(&pubkey.serialize())?;
671 match second_option {
672 Some(second_pubkey) => {
673 writer.write_all(&second_pubkey.serialize())?;
676 writer.write_all(&[0; 33])?;
681 writer.write_all(&byte_utils::be48_to_array(0))?;
685 writer.write_all(&byte_utils::be16_to_array(self.on_holder_tx_csv))?;
687 self.commitment_secrets.write(writer)?;
689 macro_rules! serialize_htlc_in_commitment {
690 ($htlc_output: expr) => {
691 writer.write_all(&[$htlc_output.offered as u8; 1])?;
692 writer.write_all(&byte_utils::be64_to_array($htlc_output.amount_msat))?;
693 writer.write_all(&byte_utils::be32_to_array($htlc_output.cltv_expiry))?;
694 writer.write_all(&$htlc_output.payment_hash.0[..])?;
695 $htlc_output.transaction_output_index.write(writer)?;
699 writer.write_all(&byte_utils::be64_to_array(self.counterparty_claimable_outpoints.len() as u64))?;
700 for (ref txid, ref htlc_infos) in self.counterparty_claimable_outpoints.iter() {
701 writer.write_all(&txid[..])?;
702 writer.write_all(&byte_utils::be64_to_array(htlc_infos.len() as u64))?;
703 for &(ref htlc_output, ref htlc_source) in htlc_infos.iter() {
704 serialize_htlc_in_commitment!(htlc_output);
705 htlc_source.as_ref().map(|b| b.as_ref()).write(writer)?;
709 writer.write_all(&byte_utils::be64_to_array(self.counterparty_commitment_txn_on_chain.len() as u64))?;
710 for (ref txid, commitment_number) in self.counterparty_commitment_txn_on_chain.iter() {
711 writer.write_all(&txid[..])?;
712 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
715 writer.write_all(&byte_utils::be64_to_array(self.counterparty_hash_commitment_number.len() as u64))?;
716 for (ref payment_hash, commitment_number) in self.counterparty_hash_commitment_number.iter() {
717 writer.write_all(&payment_hash.0[..])?;
718 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
721 if let Some(ref prev_holder_tx) = self.prev_holder_signed_commitment_tx {
722 writer.write_all(&[1; 1])?;
723 prev_holder_tx.write(writer)?;
725 writer.write_all(&[0; 1])?;
728 self.current_holder_commitment_tx.write(writer)?;
730 writer.write_all(&byte_utils::be48_to_array(self.current_counterparty_commitment_number))?;
731 writer.write_all(&byte_utils::be48_to_array(self.current_holder_commitment_number))?;
733 writer.write_all(&byte_utils::be64_to_array(self.payment_preimages.len() as u64))?;
734 for payment_preimage in self.payment_preimages.values() {
735 writer.write_all(&payment_preimage.0[..])?;
738 writer.write_all(&byte_utils::be64_to_array(self.pending_monitor_events.len() as u64))?;
739 for event in self.pending_monitor_events.iter() {
741 MonitorEvent::HTLCEvent(upd) => {
745 MonitorEvent::CommitmentTxBroadcasted(_) => 1u8.write(writer)?
749 writer.write_all(&byte_utils::be64_to_array(self.pending_events.len() as u64))?;
750 for event in self.pending_events.iter() {
751 event.write(writer)?;
754 self.best_block.block_hash().write(writer)?;
755 writer.write_all(&byte_utils::be32_to_array(self.best_block.height()))?;
757 writer.write_all(&byte_utils::be64_to_array(self.onchain_events_awaiting_threshold_conf.len() as u64))?;
758 for ref entry in self.onchain_events_awaiting_threshold_conf.iter() {
759 entry.write(writer)?;
762 (self.outputs_to_watch.len() as u64).write(writer)?;
763 for (txid, idx_scripts) in self.outputs_to_watch.iter() {
765 (idx_scripts.len() as u64).write(writer)?;
766 for (idx, script) in idx_scripts.iter() {
768 script.write(writer)?;
771 self.onchain_tx_handler.write(writer)?;
773 self.lockdown_from_offchain.write(writer)?;
774 self.holder_tx_signed.write(writer)?;
776 write_tlv_fields!(writer, {}, {});
782 impl<Signer: Sign> ChannelMonitor<Signer> {
783 pub(crate) fn new(secp_ctx: Secp256k1<secp256k1::All>, keys: Signer, shutdown_pubkey: &PublicKey,
784 on_counterparty_tx_csv: u16, destination_script: &Script, funding_info: (OutPoint, Script),
785 channel_parameters: &ChannelTransactionParameters,
786 funding_redeemscript: Script, channel_value_satoshis: u64,
787 commitment_transaction_number_obscure_factor: u64,
788 initial_holder_commitment_tx: HolderCommitmentTransaction,
789 best_block: BestBlock) -> ChannelMonitor<Signer> {
791 assert!(commitment_transaction_number_obscure_factor <= (1 << 48));
792 let our_channel_close_key_hash = WPubkeyHash::hash(&shutdown_pubkey.serialize());
793 let shutdown_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&our_channel_close_key_hash[..]).into_script();
794 let payment_key_hash = WPubkeyHash::hash(&keys.pubkeys().payment_point.serialize());
795 let counterparty_payment_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&payment_key_hash[..]).into_script();
797 let counterparty_channel_parameters = channel_parameters.counterparty_parameters.as_ref().unwrap();
798 let counterparty_delayed_payment_base_key = counterparty_channel_parameters.pubkeys.delayed_payment_basepoint;
799 let counterparty_htlc_base_key = counterparty_channel_parameters.pubkeys.htlc_basepoint;
800 let counterparty_tx_cache = CounterpartyCommitmentTransaction { counterparty_delayed_payment_base_key, counterparty_htlc_base_key, on_counterparty_tx_csv, per_htlc: HashMap::new() };
802 let channel_keys_id = keys.channel_keys_id();
803 let holder_revocation_basepoint = keys.pubkeys().revocation_basepoint;
805 // block for Rust 1.34 compat
806 let (holder_commitment_tx, current_holder_commitment_number) = {
807 let trusted_tx = initial_holder_commitment_tx.trust();
808 let txid = trusted_tx.txid();
810 let tx_keys = trusted_tx.keys();
811 let holder_commitment_tx = HolderSignedTx {
813 revocation_key: tx_keys.revocation_key,
814 a_htlc_key: tx_keys.broadcaster_htlc_key,
815 b_htlc_key: tx_keys.countersignatory_htlc_key,
816 delayed_payment_key: tx_keys.broadcaster_delayed_payment_key,
817 per_commitment_point: tx_keys.per_commitment_point,
818 feerate_per_kw: trusted_tx.feerate_per_kw(),
819 htlc_outputs: Vec::new(), // There are never any HTLCs in the initial commitment transactions
821 (holder_commitment_tx, trusted_tx.commitment_number())
824 let onchain_tx_handler =
825 OnchainTxHandler::new(destination_script.clone(), keys,
826 channel_parameters.clone(), initial_holder_commitment_tx, secp_ctx.clone());
828 let mut outputs_to_watch = HashMap::new();
829 outputs_to_watch.insert(funding_info.0.txid, vec![(funding_info.0.index as u32, funding_info.1.clone())]);
832 inner: Mutex::new(ChannelMonitorImpl {
834 commitment_transaction_number_obscure_factor,
836 destination_script: destination_script.clone(),
837 broadcasted_holder_revokable_script: None,
838 counterparty_payment_script,
842 holder_revocation_basepoint,
844 current_counterparty_commitment_txid: None,
845 prev_counterparty_commitment_txid: None,
847 counterparty_tx_cache,
848 funding_redeemscript,
849 channel_value_satoshis,
850 their_cur_revocation_points: None,
852 on_holder_tx_csv: counterparty_channel_parameters.selected_contest_delay,
854 commitment_secrets: CounterpartyCommitmentSecrets::new(),
855 counterparty_claimable_outpoints: HashMap::new(),
856 counterparty_commitment_txn_on_chain: HashMap::new(),
857 counterparty_hash_commitment_number: HashMap::new(),
859 prev_holder_signed_commitment_tx: None,
860 current_holder_commitment_tx: holder_commitment_tx,
861 current_counterparty_commitment_number: 1 << 48,
862 current_holder_commitment_number,
864 payment_preimages: HashMap::new(),
865 pending_monitor_events: Vec::new(),
866 pending_events: Vec::new(),
868 onchain_events_awaiting_threshold_conf: Vec::new(),
873 lockdown_from_offchain: false,
874 holder_tx_signed: false,
884 fn provide_secret(&self, idx: u64, secret: [u8; 32]) -> Result<(), MonitorUpdateError> {
885 self.inner.lock().unwrap().provide_secret(idx, secret)
888 /// Informs this monitor of the latest counterparty (ie non-broadcastable) commitment transaction.
889 /// The monitor watches for it to be broadcasted and then uses the HTLC information (and
890 /// possibly future revocation/preimage information) to claim outputs where possible.
891 /// We cache also the mapping hash:commitment number to lighten pruning of old preimages by watchtowers.
892 pub(crate) fn provide_latest_counterparty_commitment_tx<L: Deref>(
895 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
896 commitment_number: u64,
897 their_revocation_point: PublicKey,
899 ) where L::Target: Logger {
900 self.inner.lock().unwrap().provide_latest_counterparty_commitment_tx(
901 txid, htlc_outputs, commitment_number, their_revocation_point, logger)
905 fn provide_latest_holder_commitment_tx(
907 holder_commitment_tx: HolderCommitmentTransaction,
908 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
909 ) -> Result<(), MonitorUpdateError> {
910 self.inner.lock().unwrap().provide_latest_holder_commitment_tx(
911 holder_commitment_tx, htlc_outputs)
915 pub(crate) fn provide_payment_preimage<B: Deref, F: Deref, L: Deref>(
917 payment_hash: &PaymentHash,
918 payment_preimage: &PaymentPreimage,
923 B::Target: BroadcasterInterface,
924 F::Target: FeeEstimator,
927 self.inner.lock().unwrap().provide_payment_preimage(
928 payment_hash, payment_preimage, broadcaster, fee_estimator, logger)
931 pub(crate) fn broadcast_latest_holder_commitment_txn<B: Deref, L: Deref>(
936 B::Target: BroadcasterInterface,
939 self.inner.lock().unwrap().broadcast_latest_holder_commitment_txn(broadcaster, logger)
942 /// Updates a ChannelMonitor on the basis of some new information provided by the Channel
945 /// panics if the given update is not the next update by update_id.
946 pub fn update_monitor<B: Deref, F: Deref, L: Deref>(
948 updates: &ChannelMonitorUpdate,
952 ) -> Result<(), MonitorUpdateError>
954 B::Target: BroadcasterInterface,
955 F::Target: FeeEstimator,
958 self.inner.lock().unwrap().update_monitor(updates, broadcaster, fee_estimator, logger)
961 /// Gets the update_id from the latest ChannelMonitorUpdate which was applied to this
963 pub fn get_latest_update_id(&self) -> u64 {
964 self.inner.lock().unwrap().get_latest_update_id()
967 /// Gets the funding transaction outpoint of the channel this ChannelMonitor is monitoring for.
968 pub fn get_funding_txo(&self) -> (OutPoint, Script) {
969 self.inner.lock().unwrap().get_funding_txo().clone()
972 /// Gets a list of txids, with their output scripts (in the order they appear in the
973 /// transaction), which we must learn about spends of via block_connected().
974 pub fn get_outputs_to_watch(&self) -> Vec<(Txid, Vec<(u32, Script)>)> {
975 self.inner.lock().unwrap().get_outputs_to_watch()
976 .iter().map(|(txid, outputs)| (*txid, outputs.clone())).collect()
979 /// Loads the funding txo and outputs to watch into the given `chain::Filter` by repeatedly
980 /// calling `chain::Filter::register_output` and `chain::Filter::register_tx` until all outputs
981 /// have been registered.
982 pub fn load_outputs_to_watch<F: Deref>(&self, filter: &F) where F::Target: chain::Filter {
983 let lock = self.inner.lock().unwrap();
984 filter.register_tx(&lock.get_funding_txo().0.txid, &lock.get_funding_txo().1);
985 for (txid, outputs) in lock.get_outputs_to_watch().iter() {
986 for (index, script_pubkey) in outputs.iter() {
987 assert!(*index <= u16::max_value() as u32);
988 filter.register_output(WatchedOutput {
990 outpoint: OutPoint { txid: *txid, index: *index as u16 },
991 script_pubkey: script_pubkey.clone(),
997 /// Get the list of HTLCs who's status has been updated on chain. This should be called by
998 /// ChannelManager via [`chain::Watch::release_pending_monitor_events`].
999 pub fn get_and_clear_pending_monitor_events(&self) -> Vec<MonitorEvent> {
1000 self.inner.lock().unwrap().get_and_clear_pending_monitor_events()
1003 /// Gets the list of pending events which were generated by previous actions, clearing the list
1006 /// This is called by ChainMonitor::get_and_clear_pending_events() and is equivalent to
1007 /// EventsProvider::get_and_clear_pending_events() except that it requires &mut self as we do
1008 /// no internal locking in ChannelMonitors.
1009 pub fn get_and_clear_pending_events(&self) -> Vec<Event> {
1010 self.inner.lock().unwrap().get_and_clear_pending_events()
1013 pub(crate) fn get_min_seen_secret(&self) -> u64 {
1014 self.inner.lock().unwrap().get_min_seen_secret()
1017 pub(crate) fn get_cur_counterparty_commitment_number(&self) -> u64 {
1018 self.inner.lock().unwrap().get_cur_counterparty_commitment_number()
1021 pub(crate) fn get_cur_holder_commitment_number(&self) -> u64 {
1022 self.inner.lock().unwrap().get_cur_holder_commitment_number()
1025 /// Used by ChannelManager deserialization to broadcast the latest holder state if its copy of
1026 /// the Channel was out-of-date. You may use it to get a broadcastable holder toxic tx in case of
1027 /// fallen-behind, i.e when receiving a channel_reestablish with a proof that our counterparty side knows
1028 /// a higher revocation secret than the holder commitment number we are aware of. Broadcasting these
1029 /// transactions are UNSAFE, as they allow counterparty side to punish you. Nevertheless you may want to
1030 /// broadcast them if counterparty don't close channel with his higher commitment transaction after a
1031 /// substantial amount of time (a month or even a year) to get back funds. Best may be to contact
1032 /// out-of-band the other node operator to coordinate with him if option is available to you.
1033 /// In any-case, choice is up to the user.
1034 pub fn get_latest_holder_commitment_txn<L: Deref>(&self, logger: &L) -> Vec<Transaction>
1035 where L::Target: Logger {
1036 self.inner.lock().unwrap().get_latest_holder_commitment_txn(logger)
1039 /// Unsafe test-only version of get_latest_holder_commitment_txn used by our test framework
1040 /// to bypass HolderCommitmentTransaction state update lockdown after signature and generate
1041 /// revoked commitment transaction.
1042 #[cfg(any(test, feature = "unsafe_revoked_tx_signing"))]
1043 pub fn unsafe_get_latest_holder_commitment_txn<L: Deref>(&self, logger: &L) -> Vec<Transaction>
1044 where L::Target: Logger {
1045 self.inner.lock().unwrap().unsafe_get_latest_holder_commitment_txn(logger)
1048 /// Processes transactions in a newly connected block, which may result in any of the following:
1049 /// - update the monitor's state against resolved HTLCs
1050 /// - punish the counterparty in the case of seeing a revoked commitment transaction
1051 /// - force close the channel and claim/timeout incoming/outgoing HTLCs if near expiration
1052 /// - detect settled outputs for later spending
1053 /// - schedule and bump any in-flight claims
1055 /// Returns any new outputs to watch from `txdata`; after called, these are also included in
1056 /// [`get_outputs_to_watch`].
1058 /// [`get_outputs_to_watch`]: #method.get_outputs_to_watch
1059 pub fn block_connected<B: Deref, F: Deref, L: Deref>(
1061 header: &BlockHeader,
1062 txdata: &TransactionData,
1067 ) -> Vec<TransactionOutputs>
1069 B::Target: BroadcasterInterface,
1070 F::Target: FeeEstimator,
1073 self.inner.lock().unwrap().block_connected(
1074 header, txdata, height, broadcaster, fee_estimator, logger)
1077 /// Determines if the disconnected block contained any transactions of interest and updates
1079 pub fn block_disconnected<B: Deref, F: Deref, L: Deref>(
1081 header: &BlockHeader,
1087 B::Target: BroadcasterInterface,
1088 F::Target: FeeEstimator,
1091 self.inner.lock().unwrap().block_disconnected(
1092 header, height, broadcaster, fee_estimator, logger)
1095 /// Processes transactions confirmed in a block with the given header and height, returning new
1096 /// outputs to watch. See [`block_connected`] for details.
1098 /// Used instead of [`block_connected`] by clients that are notified of transactions rather than
1099 /// blocks. See [`chain::Confirm`] for calling expectations.
1101 /// [`block_connected`]: Self::block_connected
1102 pub fn transactions_confirmed<B: Deref, F: Deref, L: Deref>(
1104 header: &BlockHeader,
1105 txdata: &TransactionData,
1110 ) -> Vec<TransactionOutputs>
1112 B::Target: BroadcasterInterface,
1113 F::Target: FeeEstimator,
1116 self.inner.lock().unwrap().transactions_confirmed(
1117 header, txdata, height, broadcaster, fee_estimator, logger)
1120 /// Processes a transaction that was reorganized out of the chain.
1122 /// Used instead of [`block_disconnected`] by clients that are notified of transactions rather
1123 /// than blocks. See [`chain::Confirm`] for calling expectations.
1125 /// [`block_disconnected`]: Self::block_disconnected
1126 pub fn transaction_unconfirmed<B: Deref, F: Deref, L: Deref>(
1133 B::Target: BroadcasterInterface,
1134 F::Target: FeeEstimator,
1137 self.inner.lock().unwrap().transaction_unconfirmed(
1138 txid, broadcaster, fee_estimator, logger);
1141 /// Updates the monitor with the current best chain tip, returning new outputs to watch. See
1142 /// [`block_connected`] for details.
1144 /// Used instead of [`block_connected`] by clients that are notified of transactions rather than
1145 /// blocks. See [`chain::Confirm`] for calling expectations.
1147 /// [`block_connected`]: Self::block_connected
1148 pub fn best_block_updated<B: Deref, F: Deref, L: Deref>(
1150 header: &BlockHeader,
1155 ) -> Vec<TransactionOutputs>
1157 B::Target: BroadcasterInterface,
1158 F::Target: FeeEstimator,
1161 self.inner.lock().unwrap().best_block_updated(
1162 header, height, broadcaster, fee_estimator, logger)
1165 /// Returns the set of txids that should be monitored for re-organization out of the chain.
1166 pub fn get_relevant_txids(&self) -> Vec<Txid> {
1167 let inner = self.inner.lock().unwrap();
1168 let mut txids: Vec<Txid> = inner.onchain_events_awaiting_threshold_conf
1170 .map(|entry| entry.txid)
1171 .chain(inner.onchain_tx_handler.get_relevant_txids().into_iter())
1173 txids.sort_unstable();
1179 impl<Signer: Sign> ChannelMonitorImpl<Signer> {
1180 /// Inserts a revocation secret into this channel monitor. Prunes old preimages if neither
1181 /// needed by holder commitment transactions HTCLs nor by counterparty ones. Unless we haven't already seen
1182 /// counterparty commitment transaction's secret, they are de facto pruned (we can use revocation key).
1183 fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), MonitorUpdateError> {
1184 if let Err(()) = self.commitment_secrets.provide_secret(idx, secret) {
1185 return Err(MonitorUpdateError("Previous secret did not match new one"));
1188 // Prune HTLCs from the previous counterparty commitment tx so we don't generate failure/fulfill
1189 // events for now-revoked/fulfilled HTLCs.
1190 if let Some(txid) = self.prev_counterparty_commitment_txid.take() {
1191 for &mut (_, ref mut source) in self.counterparty_claimable_outpoints.get_mut(&txid).unwrap() {
1196 if !self.payment_preimages.is_empty() {
1197 let cur_holder_signed_commitment_tx = &self.current_holder_commitment_tx;
1198 let prev_holder_signed_commitment_tx = self.prev_holder_signed_commitment_tx.as_ref();
1199 let min_idx = self.get_min_seen_secret();
1200 let counterparty_hash_commitment_number = &mut self.counterparty_hash_commitment_number;
1202 self.payment_preimages.retain(|&k, _| {
1203 for &(ref htlc, _, _) in cur_holder_signed_commitment_tx.htlc_outputs.iter() {
1204 if k == htlc.payment_hash {
1208 if let Some(prev_holder_commitment_tx) = prev_holder_signed_commitment_tx {
1209 for &(ref htlc, _, _) in prev_holder_commitment_tx.htlc_outputs.iter() {
1210 if k == htlc.payment_hash {
1215 let contains = if let Some(cn) = counterparty_hash_commitment_number.get(&k) {
1222 counterparty_hash_commitment_number.remove(&k);
1231 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 {
1232 // TODO: Encrypt the htlc_outputs data with the single-hash of the commitment transaction
1233 // so that a remote monitor doesn't learn anything unless there is a malicious close.
1234 // (only maybe, sadly we cant do the same for local info, as we need to be aware of
1236 for &(ref htlc, _) in &htlc_outputs {
1237 self.counterparty_hash_commitment_number.insert(htlc.payment_hash, commitment_number);
1240 log_trace!(logger, "Tracking new counterparty commitment transaction with txid {} at commitment number {} with {} HTLC outputs", txid, commitment_number, htlc_outputs.len());
1241 self.prev_counterparty_commitment_txid = self.current_counterparty_commitment_txid.take();
1242 self.current_counterparty_commitment_txid = Some(txid);
1243 self.counterparty_claimable_outpoints.insert(txid, htlc_outputs.clone());
1244 self.current_counterparty_commitment_number = commitment_number;
1245 //TODO: Merge this into the other per-counterparty-transaction output storage stuff
1246 match self.their_cur_revocation_points {
1247 Some(old_points) => {
1248 if old_points.0 == commitment_number + 1 {
1249 self.their_cur_revocation_points = Some((old_points.0, old_points.1, Some(their_revocation_point)));
1250 } else if old_points.0 == commitment_number + 2 {
1251 if let Some(old_second_point) = old_points.2 {
1252 self.their_cur_revocation_points = Some((old_points.0 - 1, old_second_point, Some(their_revocation_point)));
1254 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1257 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1261 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1264 let mut htlcs = Vec::with_capacity(htlc_outputs.len());
1265 for htlc in htlc_outputs {
1266 if htlc.0.transaction_output_index.is_some() {
1270 self.counterparty_tx_cache.per_htlc.insert(txid, htlcs);
1273 /// Informs this monitor of the latest holder (ie broadcastable) commitment transaction. The
1274 /// monitor watches for timeouts and may broadcast it if we approach such a timeout. Thus, it
1275 /// is important that any clones of this channel monitor (including remote clones) by kept
1276 /// up-to-date as our holder commitment transaction is updated.
1277 /// Panics if set_on_holder_tx_csv has never been called.
1278 fn provide_latest_holder_commitment_tx(&mut self, holder_commitment_tx: HolderCommitmentTransaction, htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>) -> Result<(), MonitorUpdateError> {
1279 // block for Rust 1.34 compat
1280 let mut new_holder_commitment_tx = {
1281 let trusted_tx = holder_commitment_tx.trust();
1282 let txid = trusted_tx.txid();
1283 let tx_keys = trusted_tx.keys();
1284 self.current_holder_commitment_number = trusted_tx.commitment_number();
1287 revocation_key: tx_keys.revocation_key,
1288 a_htlc_key: tx_keys.broadcaster_htlc_key,
1289 b_htlc_key: tx_keys.countersignatory_htlc_key,
1290 delayed_payment_key: tx_keys.broadcaster_delayed_payment_key,
1291 per_commitment_point: tx_keys.per_commitment_point,
1292 feerate_per_kw: trusted_tx.feerate_per_kw(),
1296 self.onchain_tx_handler.provide_latest_holder_tx(holder_commitment_tx);
1297 mem::swap(&mut new_holder_commitment_tx, &mut self.current_holder_commitment_tx);
1298 self.prev_holder_signed_commitment_tx = Some(new_holder_commitment_tx);
1299 if self.holder_tx_signed {
1300 return Err(MonitorUpdateError("Latest holder commitment signed has already been signed, update is rejected"));
1305 /// Provides a payment_hash->payment_preimage mapping. Will be automatically pruned when all
1306 /// commitment_tx_infos which contain the payment hash have been revoked.
1307 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)
1308 where B::Target: BroadcasterInterface,
1309 F::Target: FeeEstimator,
1312 self.payment_preimages.insert(payment_hash.clone(), payment_preimage.clone());
1314 // If the channel is force closed, try to claim the output from this preimage.
1315 // First check if a counterparty commitment transaction has been broadcasted:
1316 macro_rules! claim_htlcs {
1317 ($commitment_number: expr, $txid: expr) => {
1318 let htlc_claim_reqs = self.get_counterparty_htlc_output_claim_reqs($commitment_number, $txid, None);
1319 self.onchain_tx_handler.update_claims_view(&Vec::new(), htlc_claim_reqs, self.best_block.height(), broadcaster, fee_estimator, logger);
1322 if let Some(txid) = self.current_counterparty_commitment_txid {
1323 if let Some(commitment_number) = self.counterparty_commitment_txn_on_chain.get(&txid) {
1324 claim_htlcs!(*commitment_number, txid);
1328 if let Some(txid) = self.prev_counterparty_commitment_txid {
1329 if let Some(commitment_number) = self.counterparty_commitment_txn_on_chain.get(&txid) {
1330 claim_htlcs!(*commitment_number, txid);
1335 // Then if a holder commitment transaction has been seen on-chain, broadcast transactions
1336 // claiming the HTLC output from each of the holder commitment transactions.
1337 // Note that we can't just use `self.holder_tx_signed`, because that only covers the case where
1338 // *we* sign a holder commitment transaction, not when e.g. a watchtower broadcasts one of our
1339 // holder commitment transactions.
1340 if self.broadcasted_holder_revokable_script.is_some() {
1341 let (claim_reqs, _) = self.get_broadcasted_holder_claims(&self.current_holder_commitment_tx, 0);
1342 self.onchain_tx_handler.update_claims_view(&Vec::new(), claim_reqs, self.best_block.height(), broadcaster, fee_estimator, logger);
1343 if let Some(ref tx) = self.prev_holder_signed_commitment_tx {
1344 let (claim_reqs, _) = self.get_broadcasted_holder_claims(&tx, 0);
1345 self.onchain_tx_handler.update_claims_view(&Vec::new(), claim_reqs, self.best_block.height(), broadcaster, fee_estimator, logger);
1350 pub(crate) fn broadcast_latest_holder_commitment_txn<B: Deref, L: Deref>(&mut self, broadcaster: &B, logger: &L)
1351 where B::Target: BroadcasterInterface,
1354 for tx in self.get_latest_holder_commitment_txn(logger).iter() {
1355 log_info!(logger, "Broadcasting local {}", log_tx!(tx));
1356 broadcaster.broadcast_transaction(tx);
1358 self.pending_monitor_events.push(MonitorEvent::CommitmentTxBroadcasted(self.funding_info.0));
1361 pub fn update_monitor<B: Deref, F: Deref, L: Deref>(&mut self, updates: &ChannelMonitorUpdate, broadcaster: &B, fee_estimator: &F, logger: &L) -> Result<(), MonitorUpdateError>
1362 where B::Target: BroadcasterInterface,
1363 F::Target: FeeEstimator,
1366 // ChannelMonitor updates may be applied after force close if we receive a
1367 // preimage for a broadcasted commitment transaction HTLC output that we'd
1368 // like to claim on-chain. If this is the case, we no longer have guaranteed
1369 // access to the monitor's update ID, so we use a sentinel value instead.
1370 if updates.update_id == CLOSED_CHANNEL_UPDATE_ID {
1371 match updates.updates[0] {
1372 ChannelMonitorUpdateStep::PaymentPreimage { .. } => {},
1373 _ => panic!("Attempted to apply post-force-close ChannelMonitorUpdate that wasn't providing a payment preimage"),
1375 assert_eq!(updates.updates.len(), 1);
1376 } else if self.latest_update_id + 1 != updates.update_id {
1377 panic!("Attempted to apply ChannelMonitorUpdates out of order, check the update_id before passing an update to update_monitor!");
1379 for update in updates.updates.iter() {
1381 ChannelMonitorUpdateStep::LatestHolderCommitmentTXInfo { commitment_tx, htlc_outputs } => {
1382 log_trace!(logger, "Updating ChannelMonitor with latest holder commitment transaction info");
1383 if self.lockdown_from_offchain { panic!(); }
1384 self.provide_latest_holder_commitment_tx(commitment_tx.clone(), htlc_outputs.clone())?
1386 ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo { commitment_txid, htlc_outputs, commitment_number, their_revocation_point } => {
1387 log_trace!(logger, "Updating ChannelMonitor with latest counterparty commitment transaction info");
1388 self.provide_latest_counterparty_commitment_tx(*commitment_txid, htlc_outputs.clone(), *commitment_number, *their_revocation_point, logger)
1390 ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage } => {
1391 log_trace!(logger, "Updating ChannelMonitor with payment preimage");
1392 self.provide_payment_preimage(&PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()), &payment_preimage, broadcaster, fee_estimator, logger)
1394 ChannelMonitorUpdateStep::CommitmentSecret { idx, secret } => {
1395 log_trace!(logger, "Updating ChannelMonitor with commitment secret");
1396 self.provide_secret(*idx, *secret)?
1398 ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast } => {
1399 log_trace!(logger, "Updating ChannelMonitor: channel force closed, should broadcast: {}", should_broadcast);
1400 self.lockdown_from_offchain = true;
1401 if *should_broadcast {
1402 self.broadcast_latest_holder_commitment_txn(broadcaster, logger);
1403 } else if !self.holder_tx_signed {
1404 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");
1406 // If we generated a MonitorEvent::CommitmentTxBroadcasted, the ChannelManager
1407 // will still give us a ChannelForceClosed event with !should_broadcast, but we
1408 // shouldn't print the scary warning above.
1409 log_info!(logger, "Channel off-chain state closed after we broadcasted our latest commitment transaction.");
1414 self.latest_update_id = updates.update_id;
1418 pub fn get_latest_update_id(&self) -> u64 {
1419 self.latest_update_id
1422 pub fn get_funding_txo(&self) -> &(OutPoint, Script) {
1426 pub fn get_outputs_to_watch(&self) -> &HashMap<Txid, Vec<(u32, Script)>> {
1427 // If we've detected a counterparty commitment tx on chain, we must include it in the set
1428 // of outputs to watch for spends of, otherwise we're likely to lose user funds. Because
1429 // its trivial to do, double-check that here.
1430 for (txid, _) in self.counterparty_commitment_txn_on_chain.iter() {
1431 self.outputs_to_watch.get(txid).expect("Counterparty commitment txn which have been broadcast should have outputs registered");
1433 &self.outputs_to_watch
1436 pub fn get_and_clear_pending_monitor_events(&mut self) -> Vec<MonitorEvent> {
1437 let mut ret = Vec::new();
1438 mem::swap(&mut ret, &mut self.pending_monitor_events);
1442 pub fn get_and_clear_pending_events(&mut self) -> Vec<Event> {
1443 let mut ret = Vec::new();
1444 mem::swap(&mut ret, &mut self.pending_events);
1448 /// Can only fail if idx is < get_min_seen_secret
1449 fn get_secret(&self, idx: u64) -> Option<[u8; 32]> {
1450 self.commitment_secrets.get_secret(idx)
1453 pub(crate) fn get_min_seen_secret(&self) -> u64 {
1454 self.commitment_secrets.get_min_seen_secret()
1457 pub(crate) fn get_cur_counterparty_commitment_number(&self) -> u64 {
1458 self.current_counterparty_commitment_number
1461 pub(crate) fn get_cur_holder_commitment_number(&self) -> u64 {
1462 self.current_holder_commitment_number
1465 /// Attempts to claim a counterparty commitment transaction's outputs using the revocation key and
1466 /// data in counterparty_claimable_outpoints. Will directly claim any HTLC outputs which expire at a
1467 /// height > height + CLTV_SHARED_CLAIM_BUFFER. In any case, will install monitoring for
1468 /// HTLC-Success/HTLC-Timeout transactions.
1469 /// Return updates for HTLC pending in the channel and failed automatically by the broadcast of
1470 /// revoked counterparty commitment tx
1471 fn check_spend_counterparty_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) -> (Vec<PackageTemplate>, TransactionOutputs) where L::Target: Logger {
1472 // Most secp and related errors trying to create keys means we have no hope of constructing
1473 // a spend transaction...so we return no transactions to broadcast
1474 let mut claimable_outpoints = Vec::new();
1475 let mut watch_outputs = Vec::new();
1477 let commitment_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
1478 let per_commitment_option = self.counterparty_claimable_outpoints.get(&commitment_txid);
1480 macro_rules! ignore_error {
1481 ( $thing : expr ) => {
1484 Err(_) => return (claimable_outpoints, (commitment_txid, watch_outputs))
1489 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);
1490 if commitment_number >= self.get_min_seen_secret() {
1491 let secret = self.get_secret(commitment_number).unwrap();
1492 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
1493 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1494 let revocation_pubkey = ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &self.holder_revocation_basepoint));
1495 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));
1497 let revokeable_redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.counterparty_tx_cache.on_counterparty_tx_csv, &delayed_key);
1498 let revokeable_p2wsh = revokeable_redeemscript.to_v0_p2wsh();
1500 // First, process non-htlc outputs (to_holder & to_counterparty)
1501 for (idx, outp) in tx.output.iter().enumerate() {
1502 if outp.script_pubkey == revokeable_p2wsh {
1503 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);
1504 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);
1505 claimable_outpoints.push(justice_package);
1509 // Then, try to find revoked htlc outputs
1510 if let Some(ref per_commitment_data) = per_commitment_option {
1511 for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
1512 if let Some(transaction_output_index) = htlc.transaction_output_index {
1513 if transaction_output_index as usize >= tx.output.len() ||
1514 tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
1515 return (claimable_outpoints, (commitment_txid, watch_outputs)); // Corrupted per_commitment_data, fuck this user
1517 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());
1518 let justice_package = PackageTemplate::build_package(commitment_txid, transaction_output_index, PackageSolvingData::RevokedHTLCOutput(revk_htlc_outp), htlc.cltv_expiry, true, height);
1519 claimable_outpoints.push(justice_package);
1524 // Last, track onchain revoked commitment transaction and fail backward outgoing HTLCs as payment path is broken
1525 if !claimable_outpoints.is_empty() || per_commitment_option.is_some() { // ie we're confident this is actually ours
1526 // We're definitely a counterparty commitment transaction!
1527 log_trace!(logger, "Got broadcast of revoked counterparty commitment transaction, going to generate general spend tx with {} inputs", claimable_outpoints.len());
1528 for (idx, outp) in tx.output.iter().enumerate() {
1529 watch_outputs.push((idx as u32, outp.clone()));
1531 self.counterparty_commitment_txn_on_chain.insert(commitment_txid, commitment_number);
1533 macro_rules! check_htlc_fails {
1534 ($txid: expr, $commitment_tx: expr) => {
1535 if let Some(ref outpoints) = self.counterparty_claimable_outpoints.get($txid) {
1536 for &(ref htlc, ref source_option) in outpoints.iter() {
1537 if let &Some(ref source) = source_option {
1538 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| {
1539 if entry.height != height { return true; }
1541 OnchainEvent::HTLCUpdate { source: ref update_source, .. } => {
1542 *update_source != **source
1547 let entry = OnchainEventEntry {
1550 event: OnchainEvent::HTLCUpdate {
1551 source: (**source).clone(),
1552 payment_hash: htlc.payment_hash.clone(),
1555 log_info!(logger, "Failing HTLC with payment_hash {} from {} counterparty commitment tx due to broadcast of revoked counterparty commitment transaction, waiting for confirmation (at height {})", log_bytes!(htlc.payment_hash.0), $commitment_tx, entry.confirmation_threshold());
1556 self.onchain_events_awaiting_threshold_conf.push(entry);
1562 if let Some(ref txid) = self.current_counterparty_commitment_txid {
1563 check_htlc_fails!(txid, "current");
1565 if let Some(ref txid) = self.prev_counterparty_commitment_txid {
1566 check_htlc_fails!(txid, "counterparty");
1568 // No need to check holder commitment txn, symmetric HTLCSource must be present as per-htlc data on counterparty commitment tx
1570 } else if let Some(per_commitment_data) = per_commitment_option {
1571 // While this isn't useful yet, there is a potential race where if a counterparty
1572 // revokes a state at the same time as the commitment transaction for that state is
1573 // confirmed, and the watchtower receives the block before the user, the user could
1574 // upload a new ChannelMonitor with the revocation secret but the watchtower has
1575 // already processed the block, resulting in the counterparty_commitment_txn_on_chain entry
1576 // not being generated by the above conditional. Thus, to be safe, we go ahead and
1578 for (idx, outp) in tx.output.iter().enumerate() {
1579 watch_outputs.push((idx as u32, outp.clone()));
1581 self.counterparty_commitment_txn_on_chain.insert(commitment_txid, commitment_number);
1583 log_trace!(logger, "Got broadcast of non-revoked counterparty commitment transaction {}", commitment_txid);
1585 macro_rules! check_htlc_fails {
1586 ($txid: expr, $commitment_tx: expr, $id: tt) => {
1587 if let Some(ref latest_outpoints) = self.counterparty_claimable_outpoints.get($txid) {
1588 $id: for &(ref htlc, ref source_option) in latest_outpoints.iter() {
1589 if let &Some(ref source) = source_option {
1590 // Check if the HTLC is present in the commitment transaction that was
1591 // broadcast, but not if it was below the dust limit, which we should
1592 // fail backwards immediately as there is no way for us to learn the
1593 // payment_preimage.
1594 // Note that if the dust limit were allowed to change between
1595 // commitment transactions we'd want to be check whether *any*
1596 // broadcastable commitment transaction has the HTLC in it, but it
1597 // cannot currently change after channel initialization, so we don't
1599 for &(ref broadcast_htlc, ref broadcast_source) in per_commitment_data.iter() {
1600 if broadcast_htlc.transaction_output_index.is_some() && Some(source) == broadcast_source.as_ref() {
1604 log_trace!(logger, "Failing HTLC with payment_hash {} from {} counterparty commitment tx due to broadcast of counterparty commitment transaction", log_bytes!(htlc.payment_hash.0), $commitment_tx);
1605 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| {
1606 if entry.height != height { return true; }
1608 OnchainEvent::HTLCUpdate { source: ref update_source, .. } => {
1609 *update_source != **source
1614 self.onchain_events_awaiting_threshold_conf.push(OnchainEventEntry {
1617 event: OnchainEvent::HTLCUpdate {
1618 source: (**source).clone(),
1619 payment_hash: htlc.payment_hash.clone(),
1627 if let Some(ref txid) = self.current_counterparty_commitment_txid {
1628 check_htlc_fails!(txid, "current", 'current_loop);
1630 if let Some(ref txid) = self.prev_counterparty_commitment_txid {
1631 check_htlc_fails!(txid, "previous", 'prev_loop);
1634 let htlc_claim_reqs = self.get_counterparty_htlc_output_claim_reqs(commitment_number, commitment_txid, Some(tx));
1635 for req in htlc_claim_reqs {
1636 claimable_outpoints.push(req);
1640 (claimable_outpoints, (commitment_txid, watch_outputs))
1643 fn get_counterparty_htlc_output_claim_reqs(&self, commitment_number: u64, commitment_txid: Txid, tx: Option<&Transaction>) -> Vec<PackageTemplate> {
1644 let mut claimable_outpoints = Vec::new();
1645 if let Some(htlc_outputs) = self.counterparty_claimable_outpoints.get(&commitment_txid) {
1646 if let Some(revocation_points) = self.their_cur_revocation_points {
1647 let revocation_point_option =
1648 // If the counterparty commitment tx is the latest valid state, use their latest
1649 // per-commitment point
1650 if revocation_points.0 == commitment_number { Some(&revocation_points.1) }
1651 else if let Some(point) = revocation_points.2.as_ref() {
1652 // If counterparty commitment tx is the state previous to the latest valid state, use
1653 // their previous per-commitment point (non-atomicity of revocation means it's valid for
1654 // them to temporarily have two valid commitment txns from our viewpoint)
1655 if revocation_points.0 == commitment_number + 1 { Some(point) } else { None }
1657 if let Some(revocation_point) = revocation_point_option {
1658 for (_, &(ref htlc, _)) in htlc_outputs.iter().enumerate() {
1659 if let Some(transaction_output_index) = htlc.transaction_output_index {
1660 if let Some(transaction) = tx {
1661 if transaction_output_index as usize >= transaction.output.len() ||
1662 transaction.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
1663 return claimable_outpoints; // Corrupted per_commitment_data, fuck this user
1666 let preimage = if htlc.offered { if let Some(p) = self.payment_preimages.get(&htlc.payment_hash) { Some(*p) } else { None } } else { None };
1667 if preimage.is_some() || !htlc.offered {
1668 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())) };
1669 let aggregation = if !htlc.offered { false } else { true };
1670 let counterparty_package = PackageTemplate::build_package(commitment_txid, transaction_output_index, counterparty_htlc_outp, htlc.cltv_expiry,aggregation, 0);
1671 claimable_outpoints.push(counterparty_package);
1681 /// Attempts to claim a counterparty HTLC-Success/HTLC-Timeout's outputs using the revocation key
1682 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 {
1683 let htlc_txid = tx.txid();
1684 if tx.input.len() != 1 || tx.output.len() != 1 || tx.input[0].witness.len() != 5 {
1685 return (Vec::new(), None)
1688 macro_rules! ignore_error {
1689 ( $thing : expr ) => {
1692 Err(_) => return (Vec::new(), None)
1697 let secret = if let Some(secret) = self.get_secret(commitment_number) { secret } else { return (Vec::new(), None); };
1698 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
1699 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1701 log_trace!(logger, "Counterparty HTLC broadcast {}:{}", htlc_txid, 0);
1702 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);
1703 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);
1704 let claimable_outpoints = vec!(justice_package);
1705 let outputs = vec![(0, tx.output[0].clone())];
1706 (claimable_outpoints, Some((htlc_txid, outputs)))
1709 // Returns (1) `PackageTemplate`s that can be given to the OnChainTxHandler, so that the handler can
1710 // broadcast transactions claiming holder HTLC commitment outputs and (2) a holder revokable
1711 // script so we can detect whether a holder transaction has been seen on-chain.
1712 fn get_broadcasted_holder_claims(&self, holder_tx: &HolderSignedTx, height: u32) -> (Vec<PackageTemplate>, Option<(Script, PublicKey, PublicKey)>) {
1713 let mut claim_requests = Vec::with_capacity(holder_tx.htlc_outputs.len());
1715 let redeemscript = chan_utils::get_revokeable_redeemscript(&holder_tx.revocation_key, self.on_holder_tx_csv, &holder_tx.delayed_payment_key);
1716 let broadcasted_holder_revokable_script = Some((redeemscript.to_v0_p2wsh(), holder_tx.per_commitment_point.clone(), holder_tx.revocation_key.clone()));
1718 for &(ref htlc, _, _) in holder_tx.htlc_outputs.iter() {
1719 if let Some(transaction_output_index) = htlc.transaction_output_index {
1720 let htlc_output = if htlc.offered {
1721 HolderHTLCOutput::build_offered(htlc.amount_msat, htlc.cltv_expiry)
1723 let payment_preimage = if let Some(preimage) = self.payment_preimages.get(&htlc.payment_hash) {
1726 // We can't build an HTLC-Success transaction without the preimage
1729 HolderHTLCOutput::build_accepted(payment_preimage, htlc.amount_msat)
1731 let htlc_package = PackageTemplate::build_package(holder_tx.txid, transaction_output_index, PackageSolvingData::HolderHTLCOutput(htlc_output), height, false, height);
1732 claim_requests.push(htlc_package);
1736 (claim_requests, broadcasted_holder_revokable_script)
1739 // Returns holder HTLC outputs to watch and react to in case of spending.
1740 fn get_broadcasted_holder_watch_outputs(&self, holder_tx: &HolderSignedTx, commitment_tx: &Transaction) -> Vec<(u32, TxOut)> {
1741 let mut watch_outputs = Vec::with_capacity(holder_tx.htlc_outputs.len());
1742 for &(ref htlc, _, _) in holder_tx.htlc_outputs.iter() {
1743 if let Some(transaction_output_index) = htlc.transaction_output_index {
1744 watch_outputs.push((transaction_output_index, commitment_tx.output[transaction_output_index as usize].clone()));
1750 /// Attempts to claim any claimable HTLCs in a commitment transaction which was not (yet)
1751 /// revoked using data in holder_claimable_outpoints.
1752 /// Should not be used if check_spend_revoked_transaction succeeds.
1753 fn check_spend_holder_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) -> (Vec<PackageTemplate>, TransactionOutputs) where L::Target: Logger {
1754 let commitment_txid = tx.txid();
1755 let mut claim_requests = Vec::new();
1756 let mut watch_outputs = Vec::new();
1758 macro_rules! wait_threshold_conf {
1759 ($source: expr, $commitment_tx: expr, $payment_hash: expr) => {
1760 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| {
1761 if entry.height != height { return true; }
1763 OnchainEvent::HTLCUpdate { source: ref update_source, .. } => {
1764 *update_source != $source
1769 let entry = OnchainEventEntry {
1770 txid: commitment_txid,
1772 event: OnchainEvent::HTLCUpdate { source: $source, payment_hash: $payment_hash },
1774 log_trace!(logger, "Failing HTLC with payment_hash {} from {} holder commitment tx due to broadcast of transaction, waiting confirmation (at height{})", log_bytes!($payment_hash.0), $commitment_tx, entry.confirmation_threshold());
1775 self.onchain_events_awaiting_threshold_conf.push(entry);
1779 macro_rules! append_onchain_update {
1780 ($updates: expr, $to_watch: expr) => {
1781 claim_requests = $updates.0;
1782 self.broadcasted_holder_revokable_script = $updates.1;
1783 watch_outputs.append(&mut $to_watch);
1787 // HTLCs set may differ between last and previous holder commitment txn, in case of one them hitting chain, ensure we cancel all HTLCs backward
1788 let mut is_holder_tx = false;
1790 if self.current_holder_commitment_tx.txid == commitment_txid {
1791 is_holder_tx = true;
1792 log_trace!(logger, "Got latest holder commitment tx broadcast, searching for available HTLCs to claim");
1793 let res = self.get_broadcasted_holder_claims(&self.current_holder_commitment_tx, height);
1794 let mut to_watch = self.get_broadcasted_holder_watch_outputs(&self.current_holder_commitment_tx, tx);
1795 append_onchain_update!(res, to_watch);
1796 } else if let &Some(ref holder_tx) = &self.prev_holder_signed_commitment_tx {
1797 if holder_tx.txid == commitment_txid {
1798 is_holder_tx = true;
1799 log_trace!(logger, "Got previous holder commitment tx broadcast, searching for available HTLCs to claim");
1800 let res = self.get_broadcasted_holder_claims(holder_tx, height);
1801 let mut to_watch = self.get_broadcasted_holder_watch_outputs(holder_tx, tx);
1802 append_onchain_update!(res, to_watch);
1806 macro_rules! fail_dust_htlcs_after_threshold_conf {
1807 ($holder_tx: expr) => {
1808 for &(ref htlc, _, ref source) in &$holder_tx.htlc_outputs {
1809 if htlc.transaction_output_index.is_none() {
1810 if let &Some(ref source) = source {
1811 wait_threshold_conf!(source.clone(), "lastest", htlc.payment_hash.clone());
1819 fail_dust_htlcs_after_threshold_conf!(self.current_holder_commitment_tx);
1820 if let &Some(ref holder_tx) = &self.prev_holder_signed_commitment_tx {
1821 fail_dust_htlcs_after_threshold_conf!(holder_tx);
1825 (claim_requests, (commitment_txid, watch_outputs))
1828 pub fn get_latest_holder_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
1829 log_trace!(logger, "Getting signed latest holder commitment transaction!");
1830 self.holder_tx_signed = true;
1831 let commitment_tx = self.onchain_tx_handler.get_fully_signed_holder_tx(&self.funding_redeemscript);
1832 let txid = commitment_tx.txid();
1833 let mut holder_transactions = vec![commitment_tx];
1834 for htlc in self.current_holder_commitment_tx.htlc_outputs.iter() {
1835 if let Some(vout) = htlc.0.transaction_output_index {
1836 let preimage = if !htlc.0.offered {
1837 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
1838 // We can't build an HTLC-Success transaction without the preimage
1841 } else if htlc.0.cltv_expiry > self.best_block.height() + 1 {
1842 // Don't broadcast HTLC-Timeout transactions immediately as they don't meet the
1843 // current locktime requirements on-chain. We will broadcast them in
1844 // `block_confirmed` when `would_broadcast_at_height` returns true.
1845 // Note that we add + 1 as transactions are broadcastable when they can be
1846 // confirmed in the next block.
1849 if let Some(htlc_tx) = self.onchain_tx_handler.get_fully_signed_htlc_tx(
1850 &::bitcoin::OutPoint { txid, vout }, &preimage) {
1851 holder_transactions.push(htlc_tx);
1855 // 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.
1856 // The data will be re-generated and tracked in check_spend_holder_transaction if we get a confirmation.
1860 #[cfg(any(test,feature = "unsafe_revoked_tx_signing"))]
1861 /// Note that this includes possibly-locktimed-in-the-future transactions!
1862 fn unsafe_get_latest_holder_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
1863 log_trace!(logger, "Getting signed copy of latest holder commitment transaction!");
1864 let commitment_tx = self.onchain_tx_handler.get_fully_signed_copy_holder_tx(&self.funding_redeemscript);
1865 let txid = commitment_tx.txid();
1866 let mut holder_transactions = vec![commitment_tx];
1867 for htlc in self.current_holder_commitment_tx.htlc_outputs.iter() {
1868 if let Some(vout) = htlc.0.transaction_output_index {
1869 let preimage = if !htlc.0.offered {
1870 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
1871 // We can't build an HTLC-Success transaction without the preimage
1875 if let Some(htlc_tx) = self.onchain_tx_handler.unsafe_get_fully_signed_htlc_tx(
1876 &::bitcoin::OutPoint { txid, vout }, &preimage) {
1877 holder_transactions.push(htlc_tx);
1884 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>
1885 where B::Target: BroadcasterInterface,
1886 F::Target: FeeEstimator,
1889 let block_hash = header.block_hash();
1890 log_trace!(logger, "New best block {} at height {}", block_hash, height);
1891 self.best_block = BestBlock::new(block_hash, height);
1893 self.transactions_confirmed(header, txdata, height, broadcaster, fee_estimator, logger)
1896 fn best_block_updated<B: Deref, F: Deref, L: Deref>(
1898 header: &BlockHeader,
1903 ) -> Vec<TransactionOutputs>
1905 B::Target: BroadcasterInterface,
1906 F::Target: FeeEstimator,
1909 let block_hash = header.block_hash();
1910 log_trace!(logger, "New best block {} at height {}", block_hash, height);
1912 if height > self.best_block.height() {
1913 self.best_block = BestBlock::new(block_hash, height);
1914 self.block_confirmed(height, vec![], vec![], vec![], broadcaster, fee_estimator, logger)
1916 self.best_block = BestBlock::new(block_hash, height);
1917 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| entry.height <= height);
1918 self.onchain_tx_handler.block_disconnected(height + 1, broadcaster, fee_estimator, logger);
1923 fn transactions_confirmed<B: Deref, F: Deref, L: Deref>(
1925 header: &BlockHeader,
1926 txdata: &TransactionData,
1931 ) -> Vec<TransactionOutputs>
1933 B::Target: BroadcasterInterface,
1934 F::Target: FeeEstimator,
1937 let txn_matched = self.filter_block(txdata);
1938 for tx in &txn_matched {
1939 let mut output_val = 0;
1940 for out in tx.output.iter() {
1941 if out.value > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
1942 output_val += out.value;
1943 if output_val > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
1947 let block_hash = header.block_hash();
1948 log_trace!(logger, "Block {} at height {} connected with {} txn matched", block_hash, height, txn_matched.len());
1950 let mut watch_outputs = Vec::new();
1951 let mut claimable_outpoints = Vec::new();
1952 for tx in &txn_matched {
1953 if tx.input.len() == 1 {
1954 // Assuming our keys were not leaked (in which case we're screwed no matter what),
1955 // commitment transactions and HTLC transactions will all only ever have one input,
1956 // which is an easy way to filter out any potential non-matching txn for lazy
1958 let prevout = &tx.input[0].previous_output;
1959 if prevout.txid == self.funding_info.0.txid && prevout.vout == self.funding_info.0.index as u32 {
1960 if (tx.input[0].sequence >> 8*3) as u8 == 0x80 && (tx.lock_time >> 8*3) as u8 == 0x20 {
1961 let (mut new_outpoints, new_outputs) = self.check_spend_counterparty_transaction(&tx, height, &logger);
1962 if !new_outputs.1.is_empty() {
1963 watch_outputs.push(new_outputs);
1965 if new_outpoints.is_empty() {
1966 let (mut new_outpoints, new_outputs) = self.check_spend_holder_transaction(&tx, height, &logger);
1967 if !new_outputs.1.is_empty() {
1968 watch_outputs.push(new_outputs);
1970 claimable_outpoints.append(&mut new_outpoints);
1972 claimable_outpoints.append(&mut new_outpoints);
1975 if let Some(&commitment_number) = self.counterparty_commitment_txn_on_chain.get(&prevout.txid) {
1976 let (mut new_outpoints, new_outputs_option) = self.check_spend_counterparty_htlc(&tx, commitment_number, height, &logger);
1977 claimable_outpoints.append(&mut new_outpoints);
1978 if let Some(new_outputs) = new_outputs_option {
1979 watch_outputs.push(new_outputs);
1984 // While all commitment/HTLC-Success/HTLC-Timeout transactions have one input, HTLCs
1985 // can also be resolved in a few other ways which can have more than one output. Thus,
1986 // we call is_resolving_htlc_output here outside of the tx.input.len() == 1 check.
1987 self.is_resolving_htlc_output(&tx, height, &logger);
1989 self.is_paying_spendable_output(&tx, height, &logger);
1992 self.block_confirmed(height, txn_matched, watch_outputs, claimable_outpoints, broadcaster, fee_estimator, logger)
1995 fn block_confirmed<B: Deref, F: Deref, L: Deref>(
1998 txn_matched: Vec<&Transaction>,
1999 mut watch_outputs: Vec<TransactionOutputs>,
2000 mut claimable_outpoints: Vec<PackageTemplate>,
2004 ) -> Vec<TransactionOutputs>
2006 B::Target: BroadcasterInterface,
2007 F::Target: FeeEstimator,
2010 let should_broadcast = self.would_broadcast_at_height(height, &logger);
2011 if should_broadcast {
2012 let funding_outp = HolderFundingOutput::build(self.funding_redeemscript.clone());
2013 let commitment_package = PackageTemplate::build_package(self.funding_info.0.txid.clone(), self.funding_info.0.index as u32, PackageSolvingData::HolderFundingOutput(funding_outp), height, false, height);
2014 claimable_outpoints.push(commitment_package);
2015 self.pending_monitor_events.push(MonitorEvent::CommitmentTxBroadcasted(self.funding_info.0));
2016 let commitment_tx = self.onchain_tx_handler.get_fully_signed_holder_tx(&self.funding_redeemscript);
2017 self.holder_tx_signed = true;
2018 let (mut new_outpoints, _) = self.get_broadcasted_holder_claims(&self.current_holder_commitment_tx, height);
2019 let new_outputs = self.get_broadcasted_holder_watch_outputs(&self.current_holder_commitment_tx, &commitment_tx);
2020 if !new_outputs.is_empty() {
2021 watch_outputs.push((self.current_holder_commitment_tx.txid.clone(), new_outputs));
2023 claimable_outpoints.append(&mut new_outpoints);
2026 // Find which on-chain events have reached their confirmation threshold.
2027 let onchain_events_awaiting_threshold_conf =
2028 self.onchain_events_awaiting_threshold_conf.drain(..).collect::<Vec<_>>();
2029 let mut onchain_events_reaching_threshold_conf = Vec::new();
2030 for entry in onchain_events_awaiting_threshold_conf {
2031 if entry.has_reached_confirmation_threshold(height) {
2032 onchain_events_reaching_threshold_conf.push(entry);
2034 self.onchain_events_awaiting_threshold_conf.push(entry);
2038 // Used to check for duplicate HTLC resolutions.
2039 #[cfg(debug_assertions)]
2040 let unmatured_htlcs: Vec<_> = self.onchain_events_awaiting_threshold_conf
2042 .filter_map(|entry| match &entry.event {
2043 OnchainEvent::HTLCUpdate { source, .. } => Some(source),
2044 OnchainEvent::MaturingOutput { .. } => None,
2047 #[cfg(debug_assertions)]
2048 let mut matured_htlcs = Vec::new();
2050 // Produce actionable events from on-chain events having reached their threshold.
2051 for entry in onchain_events_reaching_threshold_conf.drain(..) {
2053 OnchainEvent::HTLCUpdate { ref source, payment_hash } => {
2054 // Check for duplicate HTLC resolutions.
2055 #[cfg(debug_assertions)]
2058 unmatured_htlcs.iter().find(|&htlc| htlc == &source).is_none(),
2059 "An unmature HTLC transaction conflicts with a maturing one; failed to \
2060 call either transaction_unconfirmed for the conflicting transaction \
2061 or block_disconnected for a block containing it.");
2063 matured_htlcs.iter().find(|&htlc| htlc == source).is_none(),
2064 "A matured HTLC transaction conflicts with a maturing one; failed to \
2065 call either transaction_unconfirmed for the conflicting transaction \
2066 or block_disconnected for a block containing it.");
2067 matured_htlcs.push(source.clone());
2070 log_trace!(logger, "HTLC {} failure update has got enough confirmations to be passed upstream", log_bytes!(payment_hash.0));
2071 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
2072 payment_hash: payment_hash,
2073 payment_preimage: None,
2074 source: source.clone(),
2077 OnchainEvent::MaturingOutput { descriptor } => {
2078 log_trace!(logger, "Descriptor {} has got enough confirmations to be passed upstream", log_spendable!(descriptor));
2079 self.pending_events.push(Event::SpendableOutputs {
2080 outputs: vec![descriptor]
2086 self.onchain_tx_handler.update_claims_view(&txn_matched, claimable_outpoints, height, &&*broadcaster, &&*fee_estimator, &&*logger);
2088 // Determine new outputs to watch by comparing against previously known outputs to watch,
2089 // updating the latter in the process.
2090 watch_outputs.retain(|&(ref txid, ref txouts)| {
2091 let idx_and_scripts = txouts.iter().map(|o| (o.0, o.1.script_pubkey.clone())).collect();
2092 self.outputs_to_watch.insert(txid.clone(), idx_and_scripts).is_none()
2096 // If we see a transaction for which we registered outputs previously,
2097 // make sure the registered scriptpubkey at the expected index match
2098 // the actual transaction output one. We failed this case before #653.
2099 for tx in &txn_matched {
2100 if let Some(outputs) = self.get_outputs_to_watch().get(&tx.txid()) {
2101 for idx_and_script in outputs.iter() {
2102 assert!((idx_and_script.0 as usize) < tx.output.len());
2103 assert_eq!(tx.output[idx_and_script.0 as usize].script_pubkey, idx_and_script.1);
2111 pub fn block_disconnected<B: Deref, F: Deref, L: Deref>(&mut self, header: &BlockHeader, height: u32, broadcaster: B, fee_estimator: F, logger: L)
2112 where B::Target: BroadcasterInterface,
2113 F::Target: FeeEstimator,
2116 log_trace!(logger, "Block {} at height {} disconnected", header.block_hash(), height);
2119 //- htlc update there as failure-trigger tx (revoked commitment tx, non-revoked commitment tx, HTLC-timeout tx) has been disconnected
2120 //- maturing spendable output has transaction paying us has been disconnected
2121 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| entry.height < height);
2123 self.onchain_tx_handler.block_disconnected(height, broadcaster, fee_estimator, logger);
2125 self.best_block = BestBlock::new(header.prev_blockhash, height - 1);
2128 fn transaction_unconfirmed<B: Deref, F: Deref, L: Deref>(
2135 B::Target: BroadcasterInterface,
2136 F::Target: FeeEstimator,
2139 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| entry.txid != *txid);
2140 self.onchain_tx_handler.transaction_unconfirmed(txid, broadcaster, fee_estimator, logger);
2143 /// Filters a block's `txdata` for transactions spending watched outputs or for any child
2144 /// transactions thereof.
2145 fn filter_block<'a>(&self, txdata: &TransactionData<'a>) -> Vec<&'a Transaction> {
2146 let mut matched_txn = HashSet::new();
2147 txdata.iter().filter(|&&(_, tx)| {
2148 let mut matches = self.spends_watched_output(tx);
2149 for input in tx.input.iter() {
2150 if matches { break; }
2151 if matched_txn.contains(&input.previous_output.txid) {
2156 matched_txn.insert(tx.txid());
2159 }).map(|(_, tx)| *tx).collect()
2162 /// Checks if a given transaction spends any watched outputs.
2163 fn spends_watched_output(&self, tx: &Transaction) -> bool {
2164 for input in tx.input.iter() {
2165 if let Some(outputs) = self.get_outputs_to_watch().get(&input.previous_output.txid) {
2166 for (idx, _script_pubkey) in outputs.iter() {
2167 if *idx == input.previous_output.vout {
2170 // If the expected script is a known type, check that the witness
2171 // appears to be spending the correct type (ie that the match would
2172 // actually succeed in BIP 158/159-style filters).
2173 if _script_pubkey.is_v0_p2wsh() {
2174 assert_eq!(&bitcoin::Address::p2wsh(&Script::from(input.witness.last().unwrap().clone()), bitcoin::Network::Bitcoin).script_pubkey(), _script_pubkey);
2175 } else if _script_pubkey.is_v0_p2wpkh() {
2176 assert_eq!(&bitcoin::Address::p2wpkh(&bitcoin::PublicKey::from_slice(&input.witness.last().unwrap()).unwrap(), bitcoin::Network::Bitcoin).unwrap().script_pubkey(), _script_pubkey);
2177 } else { panic!(); }
2188 fn would_broadcast_at_height<L: Deref>(&self, height: u32, logger: &L) -> bool where L::Target: Logger {
2189 // We need to consider all HTLCs which are:
2190 // * in any unrevoked counterparty commitment transaction, as they could broadcast said
2191 // transactions and we'd end up in a race, or
2192 // * are in our latest holder commitment transaction, as this is the thing we will
2193 // broadcast if we go on-chain.
2194 // Note that we consider HTLCs which were below dust threshold here - while they don't
2195 // strictly imply that we need to fail the channel, we need to go ahead and fail them back
2196 // to the source, and if we don't fail the channel we will have to ensure that the next
2197 // updates that peer sends us are update_fails, failing the channel if not. It's probably
2198 // easier to just fail the channel as this case should be rare enough anyway.
2199 macro_rules! scan_commitment {
2200 ($htlcs: expr, $holder_tx: expr) => {
2201 for ref htlc in $htlcs {
2202 // For inbound HTLCs which we know the preimage for, we have to ensure we hit the
2203 // chain with enough room to claim the HTLC without our counterparty being able to
2204 // time out the HTLC first.
2205 // For outbound HTLCs which our counterparty hasn't failed/claimed, our primary
2206 // concern is being able to claim the corresponding inbound HTLC (on another
2207 // channel) before it expires. In fact, we don't even really care if our
2208 // counterparty here claims such an outbound HTLC after it expired as long as we
2209 // can still claim the corresponding HTLC. Thus, to avoid needlessly hitting the
2210 // chain when our counterparty is waiting for expiration to off-chain fail an HTLC
2211 // we give ourselves a few blocks of headroom after expiration before going
2212 // on-chain for an expired HTLC.
2213 // Note that, to avoid a potential attack whereby a node delays claiming an HTLC
2214 // from us until we've reached the point where we go on-chain with the
2215 // corresponding inbound HTLC, we must ensure that outbound HTLCs go on chain at
2216 // least CLTV_CLAIM_BUFFER blocks prior to the inbound HTLC.
2217 // aka outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS == height - CLTV_CLAIM_BUFFER
2218 // inbound_cltv == height + CLTV_CLAIM_BUFFER
2219 // outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS + CLTV_CLAIM_BUFFER <= inbound_cltv - CLTV_CLAIM_BUFFER
2220 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= inbound_cltv - outbound_cltv
2221 // CLTV_EXPIRY_DELTA <= inbound_cltv - outbound_cltv (by check in ChannelManager::decode_update_add_htlc_onion)
2222 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= CLTV_EXPIRY_DELTA
2223 // The final, above, condition is checked for statically in channelmanager
2224 // with CHECK_CLTV_EXPIRY_SANITY_2.
2225 let htlc_outbound = $holder_tx == htlc.offered;
2226 if ( htlc_outbound && htlc.cltv_expiry + LATENCY_GRACE_PERIOD_BLOCKS <= height) ||
2227 (!htlc_outbound && htlc.cltv_expiry <= height + CLTV_CLAIM_BUFFER && self.payment_preimages.contains_key(&htlc.payment_hash)) {
2228 log_info!(logger, "Force-closing channel due to {} HTLC timeout, HTLC expiry is {}", if htlc_outbound { "outbound" } else { "inbound "}, htlc.cltv_expiry);
2235 scan_commitment!(self.current_holder_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, _)| a), true);
2237 if let Some(ref txid) = self.current_counterparty_commitment_txid {
2238 if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(txid) {
2239 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
2242 if let Some(ref txid) = self.prev_counterparty_commitment_txid {
2243 if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(txid) {
2244 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
2251 /// Check if any transaction broadcasted is resolving HTLC output by a success or timeout on a holder
2252 /// or counterparty commitment tx, if so send back the source, preimage if found and payment_hash of resolved HTLC
2253 fn is_resolving_htlc_output<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) where L::Target: Logger {
2254 'outer_loop: for input in &tx.input {
2255 let mut payment_data = None;
2256 let revocation_sig_claim = (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC) && input.witness[1].len() == 33)
2257 || (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::AcceptedHTLC) && input.witness[1].len() == 33);
2258 let accepted_preimage_claim = input.witness.len() == 5 && HTLCType::scriptlen_to_htlctype(input.witness[4].len()) == Some(HTLCType::AcceptedHTLC);
2259 let offered_preimage_claim = input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC);
2261 macro_rules! log_claim {
2262 ($tx_info: expr, $holder_tx: expr, $htlc: expr, $source_avail: expr) => {
2263 // We found the output in question, but aren't failing it backwards
2264 // as we have no corresponding source and no valid counterparty commitment txid
2265 // to try a weak source binding with same-hash, same-value still-valid offered HTLC.
2266 // This implies either it is an inbound HTLC or an outbound HTLC on a revoked transaction.
2267 let outbound_htlc = $holder_tx == $htlc.offered;
2268 if ($holder_tx && revocation_sig_claim) ||
2269 (outbound_htlc && !$source_avail && (accepted_preimage_claim || offered_preimage_claim)) {
2270 log_error!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}!",
2271 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
2272 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
2273 if revocation_sig_claim { "revocation sig" } else { "preimage claim after we'd passed the HTLC resolution back" });
2275 log_info!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}",
2276 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
2277 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
2278 if revocation_sig_claim { "revocation sig" } else if accepted_preimage_claim || offered_preimage_claim { "preimage" } else { "timeout" });
2283 macro_rules! check_htlc_valid_counterparty {
2284 ($counterparty_txid: expr, $htlc_output: expr) => {
2285 if let Some(txid) = $counterparty_txid {
2286 for &(ref pending_htlc, ref pending_source) in self.counterparty_claimable_outpoints.get(&txid).unwrap() {
2287 if pending_htlc.payment_hash == $htlc_output.payment_hash && pending_htlc.amount_msat == $htlc_output.amount_msat {
2288 if let &Some(ref source) = pending_source {
2289 log_claim!("revoked counterparty commitment tx", false, pending_htlc, true);
2290 payment_data = Some(((**source).clone(), $htlc_output.payment_hash));
2299 macro_rules! scan_commitment {
2300 ($htlcs: expr, $tx_info: expr, $holder_tx: expr) => {
2301 for (ref htlc_output, source_option) in $htlcs {
2302 if Some(input.previous_output.vout) == htlc_output.transaction_output_index {
2303 if let Some(ref source) = source_option {
2304 log_claim!($tx_info, $holder_tx, htlc_output, true);
2305 // We have a resolution of an HTLC either from one of our latest
2306 // holder commitment transactions or an unrevoked counterparty commitment
2307 // transaction. This implies we either learned a preimage, the HTLC
2308 // has timed out, or we screwed up. In any case, we should now
2309 // resolve the source HTLC with the original sender.
2310 payment_data = Some(((*source).clone(), htlc_output.payment_hash));
2311 } else if !$holder_tx {
2312 check_htlc_valid_counterparty!(self.current_counterparty_commitment_txid, htlc_output);
2313 if payment_data.is_none() {
2314 check_htlc_valid_counterparty!(self.prev_counterparty_commitment_txid, htlc_output);
2317 if payment_data.is_none() {
2318 log_claim!($tx_info, $holder_tx, htlc_output, false);
2319 continue 'outer_loop;
2326 if input.previous_output.txid == self.current_holder_commitment_tx.txid {
2327 scan_commitment!(self.current_holder_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
2328 "our latest holder commitment tx", true);
2330 if let Some(ref prev_holder_signed_commitment_tx) = self.prev_holder_signed_commitment_tx {
2331 if input.previous_output.txid == prev_holder_signed_commitment_tx.txid {
2332 scan_commitment!(prev_holder_signed_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
2333 "our previous holder commitment tx", true);
2336 if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(&input.previous_output.txid) {
2337 scan_commitment!(htlc_outputs.iter().map(|&(ref a, ref b)| (a, (b.as_ref().clone()).map(|boxed| &**boxed))),
2338 "counterparty commitment tx", false);
2341 // Check that scan_commitment, above, decided there is some source worth relaying an
2342 // HTLC resolution backwards to and figure out whether we learned a preimage from it.
2343 if let Some((source, payment_hash)) = payment_data {
2344 let mut payment_preimage = PaymentPreimage([0; 32]);
2345 if accepted_preimage_claim {
2346 if !self.pending_monitor_events.iter().any(
2347 |update| if let &MonitorEvent::HTLCEvent(ref upd) = update { upd.source == source } else { false }) {
2348 payment_preimage.0.copy_from_slice(&input.witness[3]);
2349 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
2351 payment_preimage: Some(payment_preimage),
2355 } else if offered_preimage_claim {
2356 if !self.pending_monitor_events.iter().any(
2357 |update| if let &MonitorEvent::HTLCEvent(ref upd) = update {
2358 upd.source == source
2360 payment_preimage.0.copy_from_slice(&input.witness[1]);
2361 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
2363 payment_preimage: Some(payment_preimage),
2368 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| {
2369 if entry.height != height { return true; }
2371 OnchainEvent::HTLCUpdate { source: ref htlc_source, .. } => {
2372 *htlc_source != source
2377 let entry = OnchainEventEntry {
2380 event: OnchainEvent::HTLCUpdate { source: source, payment_hash: payment_hash },
2382 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());
2383 self.onchain_events_awaiting_threshold_conf.push(entry);
2389 /// Check if any transaction broadcasted is paying fund back to some address we can assume to own
2390 fn is_paying_spendable_output<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) where L::Target: Logger {
2391 let mut spendable_output = None;
2392 for (i, outp) in tx.output.iter().enumerate() { // There is max one spendable output for any channel tx, including ones generated by us
2393 if i > ::core::u16::MAX as usize {
2394 // While it is possible that an output exists on chain which is greater than the
2395 // 2^16th output in a given transaction, this is only possible if the output is not
2396 // in a lightning transaction and was instead placed there by some third party who
2397 // wishes to give us money for no reason.
2398 // Namely, any lightning transactions which we pre-sign will never have anywhere
2399 // near 2^16 outputs both because such transactions must have ~2^16 outputs who's
2400 // scripts are not longer than one byte in length and because they are inherently
2401 // non-standard due to their size.
2402 // Thus, it is completely safe to ignore such outputs, and while it may result in
2403 // us ignoring non-lightning fund to us, that is only possible if someone fills
2404 // nearly a full block with garbage just to hit this case.
2407 if outp.script_pubkey == self.destination_script {
2408 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
2409 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
2410 output: outp.clone(),
2413 } else if let Some(ref broadcasted_holder_revokable_script) = self.broadcasted_holder_revokable_script {
2414 if broadcasted_holder_revokable_script.0 == outp.script_pubkey {
2415 spendable_output = Some(SpendableOutputDescriptor::DelayedPaymentOutput(DelayedPaymentOutputDescriptor {
2416 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
2417 per_commitment_point: broadcasted_holder_revokable_script.1,
2418 to_self_delay: self.on_holder_tx_csv,
2419 output: outp.clone(),
2420 revocation_pubkey: broadcasted_holder_revokable_script.2.clone(),
2421 channel_keys_id: self.channel_keys_id,
2422 channel_value_satoshis: self.channel_value_satoshis,
2426 } else if self.counterparty_payment_script == outp.script_pubkey {
2427 spendable_output = Some(SpendableOutputDescriptor::StaticPaymentOutput(StaticPaymentOutputDescriptor {
2428 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
2429 output: outp.clone(),
2430 channel_keys_id: self.channel_keys_id,
2431 channel_value_satoshis: self.channel_value_satoshis,
2434 } else if outp.script_pubkey == self.shutdown_script {
2435 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
2436 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
2437 output: outp.clone(),
2441 if let Some(spendable_output) = spendable_output {
2442 let entry = OnchainEventEntry {
2445 event: OnchainEvent::MaturingOutput { descriptor: spendable_output.clone() },
2447 log_trace!(logger, "Maturing {} until {}", log_spendable!(spendable_output), entry.confirmation_threshold());
2448 self.onchain_events_awaiting_threshold_conf.push(entry);
2453 /// `Persist` defines behavior for persisting channel monitors: this could mean
2454 /// writing once to disk, and/or uploading to one or more backup services.
2456 /// Note that for every new monitor, you **must** persist the new `ChannelMonitor`
2457 /// to disk/backups. And, on every update, you **must** persist either the
2458 /// `ChannelMonitorUpdate` or the updated monitor itself. Otherwise, there is risk
2459 /// of situations such as revoking a transaction, then crashing before this
2460 /// revocation can be persisted, then unintentionally broadcasting a revoked
2461 /// transaction and losing money. This is a risk because previous channel states
2462 /// are toxic, so it's important that whatever channel state is persisted is
2463 /// kept up-to-date.
2464 pub trait Persist<ChannelSigner: Sign> {
2465 /// Persist a new channel's data. The data can be stored any way you want, but
2466 /// the identifier provided by Rust-Lightning is the channel's outpoint (and
2467 /// it is up to you to maintain a correct mapping between the outpoint and the
2468 /// stored channel data). Note that you **must** persist every new monitor to
2469 /// disk. See the `Persist` trait documentation for more details.
2471 /// See [`ChannelMonitor::write`] for writing out a `ChannelMonitor`,
2472 /// and [`ChannelMonitorUpdateErr`] for requirements when returning errors.
2473 fn persist_new_channel(&self, id: OutPoint, data: &ChannelMonitor<ChannelSigner>) -> Result<(), ChannelMonitorUpdateErr>;
2475 /// Update one channel's data. The provided `ChannelMonitor` has already
2476 /// applied the given update.
2478 /// Note that on every update, you **must** persist either the
2479 /// `ChannelMonitorUpdate` or the updated monitor itself to disk/backups. See
2480 /// the `Persist` trait documentation for more details.
2482 /// If an implementer chooses to persist the updates only, they need to make
2483 /// sure that all the updates are applied to the `ChannelMonitors` *before*
2484 /// the set of channel monitors is given to the `ChannelManager`
2485 /// deserialization routine. See [`ChannelMonitor::update_monitor`] for
2486 /// applying a monitor update to a monitor. If full `ChannelMonitors` are
2487 /// persisted, then there is no need to persist individual updates.
2489 /// Note that there could be a performance tradeoff between persisting complete
2490 /// channel monitors on every update vs. persisting only updates and applying
2491 /// them in batches. The size of each monitor grows `O(number of state updates)`
2492 /// whereas updates are small and `O(1)`.
2494 /// See [`ChannelMonitor::write`] for writing out a `ChannelMonitor`,
2495 /// [`ChannelMonitorUpdate::write`] for writing out an update, and
2496 /// [`ChannelMonitorUpdateErr`] for requirements when returning errors.
2497 fn update_persisted_channel(&self, id: OutPoint, update: &ChannelMonitorUpdate, data: &ChannelMonitor<ChannelSigner>) -> Result<(), ChannelMonitorUpdateErr>;
2500 impl<Signer: Sign, T: Deref, F: Deref, L: Deref> chain::Listen for (ChannelMonitor<Signer>, T, F, L)
2502 T::Target: BroadcasterInterface,
2503 F::Target: FeeEstimator,
2506 fn block_connected(&self, block: &Block, height: u32) {
2507 let txdata: Vec<_> = block.txdata.iter().enumerate().collect();
2508 self.0.block_connected(&block.header, &txdata, height, &*self.1, &*self.2, &*self.3);
2511 fn block_disconnected(&self, header: &BlockHeader, height: u32) {
2512 self.0.block_disconnected(header, height, &*self.1, &*self.2, &*self.3);
2516 impl<Signer: Sign, T: Deref, F: Deref, L: Deref> chain::Confirm for (ChannelMonitor<Signer>, T, F, L)
2518 T::Target: BroadcasterInterface,
2519 F::Target: FeeEstimator,
2522 fn transactions_confirmed(&self, header: &BlockHeader, txdata: &TransactionData, height: u32) {
2523 self.0.transactions_confirmed(header, txdata, height, &*self.1, &*self.2, &*self.3);
2526 fn transaction_unconfirmed(&self, txid: &Txid) {
2527 self.0.transaction_unconfirmed(txid, &*self.1, &*self.2, &*self.3);
2530 fn best_block_updated(&self, header: &BlockHeader, height: u32) {
2531 self.0.best_block_updated(header, height, &*self.1, &*self.2, &*self.3);
2534 fn get_relevant_txids(&self) -> Vec<Txid> {
2535 self.0.get_relevant_txids()
2539 const MAX_ALLOC_SIZE: usize = 64*1024;
2541 impl<'a, Signer: Sign, K: KeysInterface<Signer = Signer>> ReadableArgs<&'a K>
2542 for (BlockHash, ChannelMonitor<Signer>) {
2543 fn read<R: ::std::io::Read>(reader: &mut R, keys_manager: &'a K) -> Result<Self, DecodeError> {
2544 macro_rules! unwrap_obj {
2548 Err(_) => return Err(DecodeError::InvalidValue),
2553 let _ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
2555 let latest_update_id: u64 = Readable::read(reader)?;
2556 let commitment_transaction_number_obscure_factor = <U48 as Readable>::read(reader)?.0;
2558 let destination_script = Readable::read(reader)?;
2559 let broadcasted_holder_revokable_script = match <u8 as Readable>::read(reader)? {
2561 let revokable_address = Readable::read(reader)?;
2562 let per_commitment_point = Readable::read(reader)?;
2563 let revokable_script = Readable::read(reader)?;
2564 Some((revokable_address, per_commitment_point, revokable_script))
2567 _ => return Err(DecodeError::InvalidValue),
2569 let counterparty_payment_script = Readable::read(reader)?;
2570 let shutdown_script = Readable::read(reader)?;
2572 let channel_keys_id = Readable::read(reader)?;
2573 let holder_revocation_basepoint = Readable::read(reader)?;
2574 // Technically this can fail and serialize fail a round-trip, but only for serialization of
2575 // barely-init'd ChannelMonitors that we can't do anything with.
2576 let outpoint = OutPoint {
2577 txid: Readable::read(reader)?,
2578 index: Readable::read(reader)?,
2580 let funding_info = (outpoint, Readable::read(reader)?);
2581 let current_counterparty_commitment_txid = Readable::read(reader)?;
2582 let prev_counterparty_commitment_txid = Readable::read(reader)?;
2584 let counterparty_tx_cache = Readable::read(reader)?;
2585 let funding_redeemscript = Readable::read(reader)?;
2586 let channel_value_satoshis = Readable::read(reader)?;
2588 let their_cur_revocation_points = {
2589 let first_idx = <U48 as Readable>::read(reader)?.0;
2593 let first_point = Readable::read(reader)?;
2594 let second_point_slice: [u8; 33] = Readable::read(reader)?;
2595 if second_point_slice[0..32] == [0; 32] && second_point_slice[32] == 0 {
2596 Some((first_idx, first_point, None))
2598 Some((first_idx, first_point, Some(unwrap_obj!(PublicKey::from_slice(&second_point_slice)))))
2603 let on_holder_tx_csv: u16 = Readable::read(reader)?;
2605 let commitment_secrets = Readable::read(reader)?;
2607 macro_rules! read_htlc_in_commitment {
2610 let offered: bool = Readable::read(reader)?;
2611 let amount_msat: u64 = Readable::read(reader)?;
2612 let cltv_expiry: u32 = Readable::read(reader)?;
2613 let payment_hash: PaymentHash = Readable::read(reader)?;
2614 let transaction_output_index: Option<u32> = Readable::read(reader)?;
2616 HTLCOutputInCommitment {
2617 offered, amount_msat, cltv_expiry, payment_hash, transaction_output_index
2623 let counterparty_claimable_outpoints_len: u64 = Readable::read(reader)?;
2624 let mut counterparty_claimable_outpoints = HashMap::with_capacity(cmp::min(counterparty_claimable_outpoints_len as usize, MAX_ALLOC_SIZE / 64));
2625 for _ in 0..counterparty_claimable_outpoints_len {
2626 let txid: Txid = Readable::read(reader)?;
2627 let htlcs_count: u64 = Readable::read(reader)?;
2628 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
2629 for _ in 0..htlcs_count {
2630 htlcs.push((read_htlc_in_commitment!(), <Option<HTLCSource> as Readable>::read(reader)?.map(|o: HTLCSource| Box::new(o))));
2632 if let Some(_) = counterparty_claimable_outpoints.insert(txid, htlcs) {
2633 return Err(DecodeError::InvalidValue);
2637 let counterparty_commitment_txn_on_chain_len: u64 = Readable::read(reader)?;
2638 let mut counterparty_commitment_txn_on_chain = HashMap::with_capacity(cmp::min(counterparty_commitment_txn_on_chain_len as usize, MAX_ALLOC_SIZE / 32));
2639 for _ in 0..counterparty_commitment_txn_on_chain_len {
2640 let txid: Txid = Readable::read(reader)?;
2641 let commitment_number = <U48 as Readable>::read(reader)?.0;
2642 if let Some(_) = counterparty_commitment_txn_on_chain.insert(txid, commitment_number) {
2643 return Err(DecodeError::InvalidValue);
2647 let counterparty_hash_commitment_number_len: u64 = Readable::read(reader)?;
2648 let mut counterparty_hash_commitment_number = HashMap::with_capacity(cmp::min(counterparty_hash_commitment_number_len as usize, MAX_ALLOC_SIZE / 32));
2649 for _ in 0..counterparty_hash_commitment_number_len {
2650 let payment_hash: PaymentHash = Readable::read(reader)?;
2651 let commitment_number = <U48 as Readable>::read(reader)?.0;
2652 if let Some(_) = counterparty_hash_commitment_number.insert(payment_hash, commitment_number) {
2653 return Err(DecodeError::InvalidValue);
2657 let prev_holder_signed_commitment_tx = match <u8 as Readable>::read(reader)? {
2660 Some(Readable::read(reader)?)
2662 _ => return Err(DecodeError::InvalidValue),
2664 let current_holder_commitment_tx = Readable::read(reader)?;
2666 let current_counterparty_commitment_number = <U48 as Readable>::read(reader)?.0;
2667 let current_holder_commitment_number = <U48 as Readable>::read(reader)?.0;
2669 let payment_preimages_len: u64 = Readable::read(reader)?;
2670 let mut payment_preimages = HashMap::with_capacity(cmp::min(payment_preimages_len as usize, MAX_ALLOC_SIZE / 32));
2671 for _ in 0..payment_preimages_len {
2672 let preimage: PaymentPreimage = Readable::read(reader)?;
2673 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
2674 if let Some(_) = payment_preimages.insert(hash, preimage) {
2675 return Err(DecodeError::InvalidValue);
2679 let pending_monitor_events_len: u64 = Readable::read(reader)?;
2680 let mut pending_monitor_events = Vec::with_capacity(cmp::min(pending_monitor_events_len as usize, MAX_ALLOC_SIZE / (32 + 8*3)));
2681 for _ in 0..pending_monitor_events_len {
2682 let ev = match <u8 as Readable>::read(reader)? {
2683 0 => MonitorEvent::HTLCEvent(Readable::read(reader)?),
2684 1 => MonitorEvent::CommitmentTxBroadcasted(funding_info.0),
2685 _ => return Err(DecodeError::InvalidValue)
2687 pending_monitor_events.push(ev);
2690 let pending_events_len: u64 = Readable::read(reader)?;
2691 let mut pending_events = Vec::with_capacity(cmp::min(pending_events_len as usize, MAX_ALLOC_SIZE / mem::size_of::<Event>()));
2692 for _ in 0..pending_events_len {
2693 if let Some(event) = MaybeReadable::read(reader)? {
2694 pending_events.push(event);
2698 let best_block = BestBlock::new(Readable::read(reader)?, Readable::read(reader)?);
2700 let waiting_threshold_conf_len: u64 = Readable::read(reader)?;
2701 let mut onchain_events_awaiting_threshold_conf = Vec::with_capacity(cmp::min(waiting_threshold_conf_len as usize, MAX_ALLOC_SIZE / 128));
2702 for _ in 0..waiting_threshold_conf_len {
2703 onchain_events_awaiting_threshold_conf.push(Readable::read(reader)?);
2706 let outputs_to_watch_len: u64 = Readable::read(reader)?;
2707 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>>())));
2708 for _ in 0..outputs_to_watch_len {
2709 let txid = Readable::read(reader)?;
2710 let outputs_len: u64 = Readable::read(reader)?;
2711 let mut outputs = Vec::with_capacity(cmp::min(outputs_len as usize, MAX_ALLOC_SIZE / (mem::size_of::<u32>() + mem::size_of::<Script>())));
2712 for _ in 0..outputs_len {
2713 outputs.push((Readable::read(reader)?, Readable::read(reader)?));
2715 if let Some(_) = outputs_to_watch.insert(txid, outputs) {
2716 return Err(DecodeError::InvalidValue);
2719 let onchain_tx_handler = ReadableArgs::read(reader, keys_manager)?;
2721 let lockdown_from_offchain = Readable::read(reader)?;
2722 let holder_tx_signed = Readable::read(reader)?;
2724 read_tlv_fields!(reader, {}, {});
2726 let mut secp_ctx = Secp256k1::new();
2727 secp_ctx.seeded_randomize(&keys_manager.get_secure_random_bytes());
2729 Ok((best_block.block_hash(), ChannelMonitor {
2730 inner: Mutex::new(ChannelMonitorImpl {
2732 commitment_transaction_number_obscure_factor,
2735 broadcasted_holder_revokable_script,
2736 counterparty_payment_script,
2740 holder_revocation_basepoint,
2742 current_counterparty_commitment_txid,
2743 prev_counterparty_commitment_txid,
2745 counterparty_tx_cache,
2746 funding_redeemscript,
2747 channel_value_satoshis,
2748 their_cur_revocation_points,
2753 counterparty_claimable_outpoints,
2754 counterparty_commitment_txn_on_chain,
2755 counterparty_hash_commitment_number,
2757 prev_holder_signed_commitment_tx,
2758 current_holder_commitment_tx,
2759 current_counterparty_commitment_number,
2760 current_holder_commitment_number,
2763 pending_monitor_events,
2766 onchain_events_awaiting_threshold_conf,
2771 lockdown_from_offchain,
2784 use bitcoin::blockdata::script::{Script, Builder};
2785 use bitcoin::blockdata::opcodes;
2786 use bitcoin::blockdata::transaction::{Transaction, TxIn, TxOut, SigHashType};
2787 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
2788 use bitcoin::util::bip143;
2789 use bitcoin::hashes::Hash;
2790 use bitcoin::hashes::sha256::Hash as Sha256;
2791 use bitcoin::hashes::hex::FromHex;
2792 use bitcoin::hash_types::Txid;
2793 use bitcoin::network::constants::Network;
2795 use chain::channelmonitor::ChannelMonitor;
2796 use chain::package::{WEIGHT_OFFERED_HTLC, WEIGHT_RECEIVED_HTLC, WEIGHT_REVOKED_OFFERED_HTLC, WEIGHT_REVOKED_RECEIVED_HTLC, WEIGHT_REVOKED_OUTPUT};
2797 use chain::transaction::OutPoint;
2798 use ln::{PaymentPreimage, PaymentHash};
2799 use ln::channelmanager::BestBlock;
2801 use ln::chan_utils::{HTLCOutputInCommitment, ChannelPublicKeys, ChannelTransactionParameters, HolderCommitmentTransaction, CounterpartyChannelTransactionParameters};
2802 use util::test_utils::{TestLogger, TestBroadcaster, TestFeeEstimator};
2803 use bitcoin::secp256k1::key::{SecretKey,PublicKey};
2804 use bitcoin::secp256k1::Secp256k1;
2805 use std::sync::{Arc, Mutex};
2806 use chain::keysinterface::InMemorySigner;
2810 fn test_prune_preimages() {
2811 let secp_ctx = Secp256k1::new();
2812 let logger = Arc::new(TestLogger::new());
2813 let broadcaster = Arc::new(TestBroadcaster{txn_broadcasted: Mutex::new(Vec::new()), blocks: Arc::new(Mutex::new(Vec::new()))});
2814 let fee_estimator = Arc::new(TestFeeEstimator { sat_per_kw: 253 });
2816 let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
2817 let dummy_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
2819 let mut preimages = Vec::new();
2822 let preimage = PaymentPreimage([i; 32]);
2823 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
2824 preimages.push((preimage, hash));
2828 macro_rules! preimages_slice_to_htlc_outputs {
2829 ($preimages_slice: expr) => {
2831 let mut res = Vec::new();
2832 for (idx, preimage) in $preimages_slice.iter().enumerate() {
2833 res.push((HTLCOutputInCommitment {
2837 payment_hash: preimage.1.clone(),
2838 transaction_output_index: Some(idx as u32),
2845 macro_rules! preimages_to_holder_htlcs {
2846 ($preimages_slice: expr) => {
2848 let mut inp = preimages_slice_to_htlc_outputs!($preimages_slice);
2849 let res: Vec<_> = inp.drain(..).map(|e| { (e.0, None, e.1) }).collect();
2855 macro_rules! test_preimages_exist {
2856 ($preimages_slice: expr, $monitor: expr) => {
2857 for preimage in $preimages_slice {
2858 assert!($monitor.inner.lock().unwrap().payment_preimages.contains_key(&preimage.1));
2863 let keys = InMemorySigner::new(
2865 SecretKey::from_slice(&[41; 32]).unwrap(),
2866 SecretKey::from_slice(&[41; 32]).unwrap(),
2867 SecretKey::from_slice(&[41; 32]).unwrap(),
2868 SecretKey::from_slice(&[41; 32]).unwrap(),
2869 SecretKey::from_slice(&[41; 32]).unwrap(),
2875 let counterparty_pubkeys = ChannelPublicKeys {
2876 funding_pubkey: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[44; 32]).unwrap()),
2877 revocation_basepoint: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()),
2878 payment_point: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[46; 32]).unwrap()),
2879 delayed_payment_basepoint: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[47; 32]).unwrap()),
2880 htlc_basepoint: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[48; 32]).unwrap())
2882 let funding_outpoint = OutPoint { txid: Default::default(), index: u16::max_value() };
2883 let channel_parameters = ChannelTransactionParameters {
2884 holder_pubkeys: keys.holder_channel_pubkeys.clone(),
2885 holder_selected_contest_delay: 66,
2886 is_outbound_from_holder: true,
2887 counterparty_parameters: Some(CounterpartyChannelTransactionParameters {
2888 pubkeys: counterparty_pubkeys,
2889 selected_contest_delay: 67,
2891 funding_outpoint: Some(funding_outpoint),
2893 // Prune with one old state and a holder commitment tx holding a few overlaps with the
2895 let best_block = BestBlock::from_genesis(Network::Testnet);
2896 let monitor = ChannelMonitor::new(Secp256k1::new(), keys,
2897 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap()), 0, &Script::new(),
2898 (OutPoint { txid: Txid::from_slice(&[43; 32]).unwrap(), index: 0 }, Script::new()),
2899 &channel_parameters,
2900 Script::new(), 46, 0,
2901 HolderCommitmentTransaction::dummy(), best_block);
2903 monitor.provide_latest_holder_commitment_tx(HolderCommitmentTransaction::dummy(), preimages_to_holder_htlcs!(preimages[0..10])).unwrap();
2904 let dummy_txid = dummy_tx.txid();
2905 monitor.provide_latest_counterparty_commitment_tx(dummy_txid, preimages_slice_to_htlc_outputs!(preimages[5..15]), 281474976710655, dummy_key, &logger);
2906 monitor.provide_latest_counterparty_commitment_tx(dummy_txid, preimages_slice_to_htlc_outputs!(preimages[15..20]), 281474976710654, dummy_key, &logger);
2907 monitor.provide_latest_counterparty_commitment_tx(dummy_txid, preimages_slice_to_htlc_outputs!(preimages[17..20]), 281474976710653, dummy_key, &logger);
2908 monitor.provide_latest_counterparty_commitment_tx(dummy_txid, preimages_slice_to_htlc_outputs!(preimages[18..20]), 281474976710652, dummy_key, &logger);
2909 for &(ref preimage, ref hash) in preimages.iter() {
2910 monitor.provide_payment_preimage(hash, preimage, &broadcaster, &fee_estimator, &logger);
2913 // Now provide a secret, pruning preimages 10-15
2914 let mut secret = [0; 32];
2915 secret[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2916 monitor.provide_secret(281474976710655, secret.clone()).unwrap();
2917 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 15);
2918 test_preimages_exist!(&preimages[0..10], monitor);
2919 test_preimages_exist!(&preimages[15..20], monitor);
2921 // Now provide a further secret, pruning preimages 15-17
2922 secret[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2923 monitor.provide_secret(281474976710654, secret.clone()).unwrap();
2924 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 13);
2925 test_preimages_exist!(&preimages[0..10], monitor);
2926 test_preimages_exist!(&preimages[17..20], monitor);
2928 // Now update holder commitment tx info, pruning only element 18 as we still care about the
2929 // previous commitment tx's preimages too
2930 monitor.provide_latest_holder_commitment_tx(HolderCommitmentTransaction::dummy(), preimages_to_holder_htlcs!(preimages[0..5])).unwrap();
2931 secret[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2932 monitor.provide_secret(281474976710653, secret.clone()).unwrap();
2933 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 12);
2934 test_preimages_exist!(&preimages[0..10], monitor);
2935 test_preimages_exist!(&preimages[18..20], monitor);
2937 // But if we do it again, we'll prune 5-10
2938 monitor.provide_latest_holder_commitment_tx(HolderCommitmentTransaction::dummy(), preimages_to_holder_htlcs!(preimages[0..3])).unwrap();
2939 secret[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2940 monitor.provide_secret(281474976710652, secret.clone()).unwrap();
2941 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 5);
2942 test_preimages_exist!(&preimages[0..5], monitor);
2946 fn test_claim_txn_weight_computation() {
2947 // We test Claim txn weight, knowing that we want expected weigth and
2948 // not actual case to avoid sigs and time-lock delays hell variances.
2950 let secp_ctx = Secp256k1::new();
2951 let privkey = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
2952 let pubkey = PublicKey::from_secret_key(&secp_ctx, &privkey);
2953 let mut sum_actual_sigs = 0;
2955 macro_rules! sign_input {
2956 ($sighash_parts: expr, $idx: expr, $amount: expr, $weight: expr, $sum_actual_sigs: expr) => {
2957 let htlc = HTLCOutputInCommitment {
2958 offered: if *$weight == WEIGHT_REVOKED_OFFERED_HTLC || *$weight == WEIGHT_OFFERED_HTLC { true } else { false },
2960 cltv_expiry: 2 << 16,
2961 payment_hash: PaymentHash([1; 32]),
2962 transaction_output_index: Some($idx as u32),
2964 let redeem_script = if *$weight == WEIGHT_REVOKED_OUTPUT { chan_utils::get_revokeable_redeemscript(&pubkey, 256, &pubkey) } else { chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &pubkey, &pubkey, &pubkey) };
2965 let sighash = hash_to_message!(&$sighash_parts.signature_hash($idx, &redeem_script, $amount, SigHashType::All)[..]);
2966 let sig = secp_ctx.sign(&sighash, &privkey);
2967 $sighash_parts.access_witness($idx).push(sig.serialize_der().to_vec());
2968 $sighash_parts.access_witness($idx)[0].push(SigHashType::All as u8);
2969 sum_actual_sigs += $sighash_parts.access_witness($idx)[0].len();
2970 if *$weight == WEIGHT_REVOKED_OUTPUT {
2971 $sighash_parts.access_witness($idx).push(vec!(1));
2972 } else if *$weight == WEIGHT_REVOKED_OFFERED_HTLC || *$weight == WEIGHT_REVOKED_RECEIVED_HTLC {
2973 $sighash_parts.access_witness($idx).push(pubkey.clone().serialize().to_vec());
2974 } else if *$weight == WEIGHT_RECEIVED_HTLC {
2975 $sighash_parts.access_witness($idx).push(vec![0]);
2977 $sighash_parts.access_witness($idx).push(PaymentPreimage([1; 32]).0.to_vec());
2979 $sighash_parts.access_witness($idx).push(redeem_script.into_bytes());
2980 println!("witness[0] {}", $sighash_parts.access_witness($idx)[0].len());
2981 println!("witness[1] {}", $sighash_parts.access_witness($idx)[1].len());
2982 println!("witness[2] {}", $sighash_parts.access_witness($idx)[2].len());
2986 let script_pubkey = Builder::new().push_opcode(opcodes::all::OP_RETURN).into_script();
2987 let txid = Txid::from_hex("56944c5d3f98413ef45cf54545538103cc9f298e0575820ad3591376e2e0f65d").unwrap();
2989 // Justice tx with 1 to_holder, 2 revoked offered HTLCs, 1 revoked received HTLCs
2990 let mut claim_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
2992 claim_tx.input.push(TxIn {
2993 previous_output: BitcoinOutPoint {
2997 script_sig: Script::new(),
2998 sequence: 0xfffffffd,
2999 witness: Vec::new(),
3002 claim_tx.output.push(TxOut {
3003 script_pubkey: script_pubkey.clone(),
3006 let base_weight = claim_tx.get_weight();
3007 let inputs_weight = vec![WEIGHT_REVOKED_OUTPUT, WEIGHT_REVOKED_OFFERED_HTLC, WEIGHT_REVOKED_OFFERED_HTLC, WEIGHT_REVOKED_RECEIVED_HTLC];
3008 let mut inputs_total_weight = 2; // count segwit flags
3010 let mut sighash_parts = bip143::SigHashCache::new(&mut claim_tx);
3011 for (idx, inp) in inputs_weight.iter().enumerate() {
3012 sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs);
3013 inputs_total_weight += inp;
3016 assert_eq!(base_weight + inputs_total_weight as usize, claim_tx.get_weight() + /* max_length_sig */ (73 * inputs_weight.len() - sum_actual_sigs));
3018 // Claim tx with 1 offered HTLCs, 3 received HTLCs
3019 claim_tx.input.clear();
3020 sum_actual_sigs = 0;
3022 claim_tx.input.push(TxIn {
3023 previous_output: BitcoinOutPoint {
3027 script_sig: Script::new(),
3028 sequence: 0xfffffffd,
3029 witness: Vec::new(),
3032 let base_weight = claim_tx.get_weight();
3033 let inputs_weight = vec![WEIGHT_OFFERED_HTLC, WEIGHT_RECEIVED_HTLC, WEIGHT_RECEIVED_HTLC, WEIGHT_RECEIVED_HTLC];
3034 let mut inputs_total_weight = 2; // count segwit flags
3036 let mut sighash_parts = bip143::SigHashCache::new(&mut claim_tx);
3037 for (idx, inp) in inputs_weight.iter().enumerate() {
3038 sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs);
3039 inputs_total_weight += inp;
3042 assert_eq!(base_weight + inputs_total_weight as usize, claim_tx.get_weight() + /* max_length_sig */ (73 * inputs_weight.len() - sum_actual_sigs));
3044 // Justice tx with 1 revoked HTLC-Success tx output
3045 claim_tx.input.clear();
3046 sum_actual_sigs = 0;
3047 claim_tx.input.push(TxIn {
3048 previous_output: BitcoinOutPoint {
3052 script_sig: Script::new(),
3053 sequence: 0xfffffffd,
3054 witness: Vec::new(),
3056 let base_weight = claim_tx.get_weight();
3057 let inputs_weight = vec![WEIGHT_REVOKED_OUTPUT];
3058 let mut inputs_total_weight = 2; // count segwit flags
3060 let mut sighash_parts = bip143::SigHashCache::new(&mut claim_tx);
3061 for (idx, inp) in inputs_weight.iter().enumerate() {
3062 sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs);
3063 inputs_total_weight += inp;
3066 assert_eq!(base_weight + inputs_total_weight as usize, claim_tx.get_weight() + /* max_length_isg */ (73 * inputs_weight.len() - sum_actual_sigs));
3069 // Further testing is done in the ChannelManager integration tests.