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 latest ChannelMonitor must always be actively monitoring for chain updates (and no out-of-date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::BlockHeader;
24 use bitcoin::blockdata::transaction::{OutPoint as BitcoinOutPoint, 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, ecdsa::Signature};
33 use bitcoin::secp256k1::{SecretKey, PublicKey};
34 use bitcoin::secp256k1;
36 use crate::ln::{PaymentHash, PaymentPreimage};
37 use crate::ln::msgs::DecodeError;
38 use crate::ln::chan_utils;
39 use crate::ln::chan_utils::{CounterpartyCommitmentSecrets, HTLCOutputInCommitment, HTLCClaim, ChannelTransactionParameters, HolderCommitmentTransaction};
40 use crate::ln::channelmanager::{HTLCSource, SentHTLCId};
42 use crate::chain::{BestBlock, WatchedOutput};
43 use crate::chain::chaininterface::{BroadcasterInterface, FeeEstimator, LowerBoundedFeeEstimator};
44 use crate::chain::transaction::{OutPoint, TransactionData};
45 use crate::sign::{SpendableOutputDescriptor, StaticPaymentOutputDescriptor, DelayedPaymentOutputDescriptor, WriteableEcdsaChannelSigner, SignerProvider, EntropySource};
47 use crate::chain::onchaintx::ClaimEvent;
48 use crate::chain::onchaintx::OnchainTxHandler;
49 use crate::chain::package::{CounterpartyOfferedHTLCOutput, CounterpartyReceivedHTLCOutput, HolderFundingOutput, HolderHTLCOutput, PackageSolvingData, PackageTemplate, RevokedOutput, RevokedHTLCOutput};
50 use crate::chain::Filter;
51 use crate::util::logger::Logger;
52 use crate::util::ser::{Readable, ReadableArgs, RequiredWrapper, MaybeReadable, UpgradableRequired, Writer, Writeable, U48};
53 use crate::util::byte_utils;
54 use crate::events::Event;
56 use crate::events::bump_transaction::{AnchorDescriptor, HTLCDescriptor, BumpTransactionEvent};
58 use crate::prelude::*;
60 use crate::io::{self, Error};
61 use core::convert::TryInto;
63 use crate::sync::{Mutex, LockTestExt};
65 /// An update generated by the underlying channel itself which contains some new information the
66 /// [`ChannelMonitor`] should be made aware of.
68 /// Because this represents only a small number of updates to the underlying state, it is generally
69 /// much smaller than a full [`ChannelMonitor`]. However, for large single commitment transaction
70 /// updates (e.g. ones during which there are hundreds of HTLCs pending on the commitment
71 /// transaction), a single update may reach upwards of 1 MiB in serialized size.
72 #[derive(Clone, PartialEq, Eq)]
74 pub struct ChannelMonitorUpdate {
75 pub(crate) updates: Vec<ChannelMonitorUpdateStep>,
76 /// The sequence number of this update. Updates *must* be replayed in-order according to this
77 /// sequence number (and updates may panic if they are not). The update_id values are strictly
78 /// increasing and increase by one for each new update, with two exceptions specified below.
80 /// This sequence number is also used to track up to which points updates which returned
81 /// [`ChannelMonitorUpdateStatus::InProgress`] have been applied to all copies of a given
82 /// ChannelMonitor when ChannelManager::channel_monitor_updated is called.
84 /// The only instances we allow where update_id values are not strictly increasing have a
85 /// special update ID of [`CLOSED_CHANNEL_UPDATE_ID`]. This update ID is used for updates that
86 /// will force close the channel by broadcasting the latest commitment transaction or
87 /// special post-force-close updates, like providing preimages necessary to claim outputs on the
88 /// broadcast commitment transaction. See its docs for more details.
90 /// [`ChannelMonitorUpdateStatus::InProgress`]: super::ChannelMonitorUpdateStatus::InProgress
94 /// The update ID used for a [`ChannelMonitorUpdate`] that is either:
96 /// (1) attempting to force close the channel by broadcasting our latest commitment transaction or
97 /// (2) providing a preimage (after the channel has been force closed) from a forward link that
98 /// allows us to spend an HTLC output on this channel's (the backward link's) broadcasted
99 /// commitment transaction.
101 /// No other [`ChannelMonitorUpdate`]s are allowed after force-close.
102 pub const CLOSED_CHANNEL_UPDATE_ID: u64 = core::u64::MAX;
104 impl Writeable for ChannelMonitorUpdate {
105 fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
106 write_ver_prefix!(w, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
107 self.update_id.write(w)?;
108 (self.updates.len() as u64).write(w)?;
109 for update_step in self.updates.iter() {
110 update_step.write(w)?;
112 write_tlv_fields!(w, {});
116 impl Readable for ChannelMonitorUpdate {
117 fn read<R: io::Read>(r: &mut R) -> Result<Self, DecodeError> {
118 let _ver = read_ver_prefix!(r, SERIALIZATION_VERSION);
119 let update_id: u64 = Readable::read(r)?;
120 let len: u64 = Readable::read(r)?;
121 let mut updates = Vec::with_capacity(cmp::min(len as usize, MAX_ALLOC_SIZE / ::core::mem::size_of::<ChannelMonitorUpdateStep>()));
123 if let Some(upd) = MaybeReadable::read(r)? {
127 read_tlv_fields!(r, {});
128 Ok(Self { update_id, updates })
132 /// An event to be processed by the ChannelManager.
133 #[derive(Clone, PartialEq, Eq)]
134 pub enum MonitorEvent {
135 /// A monitor event containing an HTLCUpdate.
136 HTLCEvent(HTLCUpdate),
138 /// A monitor event that the Channel's commitment transaction was confirmed.
139 CommitmentTxConfirmed(OutPoint),
141 /// Indicates a [`ChannelMonitor`] update has completed. See
142 /// [`ChannelMonitorUpdateStatus::InProgress`] for more information on how this is used.
144 /// [`ChannelMonitorUpdateStatus::InProgress`]: super::ChannelMonitorUpdateStatus::InProgress
146 /// The funding outpoint of the [`ChannelMonitor`] that was updated
147 funding_txo: OutPoint,
148 /// The Update ID from [`ChannelMonitorUpdate::update_id`] which was applied or
149 /// [`ChannelMonitor::get_latest_update_id`].
151 /// Note that this should only be set to a given update's ID if all previous updates for the
152 /// same [`ChannelMonitor`] have been applied and persisted.
153 monitor_update_id: u64,
156 /// Indicates a [`ChannelMonitor`] update has failed. See
157 /// [`ChannelMonitorUpdateStatus::PermanentFailure`] for more information on how this is used.
159 /// [`ChannelMonitorUpdateStatus::PermanentFailure`]: super::ChannelMonitorUpdateStatus::PermanentFailure
160 UpdateFailed(OutPoint),
162 impl_writeable_tlv_based_enum_upgradable!(MonitorEvent,
163 // Note that Completed and UpdateFailed are currently never serialized to disk as they are
164 // generated only in ChainMonitor
166 (0, funding_txo, required),
167 (2, monitor_update_id, required),
171 (4, CommitmentTxConfirmed),
175 /// Simple structure sent back by `chain::Watch` when an HTLC from a forward channel is detected on
176 /// chain. Used to update the corresponding HTLC in the backward channel. Failing to pass the
177 /// preimage claim backward will lead to loss of funds.
178 #[derive(Clone, PartialEq, Eq)]
179 pub struct HTLCUpdate {
180 pub(crate) payment_hash: PaymentHash,
181 pub(crate) payment_preimage: Option<PaymentPreimage>,
182 pub(crate) source: HTLCSource,
183 pub(crate) htlc_value_satoshis: Option<u64>,
185 impl_writeable_tlv_based!(HTLCUpdate, {
186 (0, payment_hash, required),
187 (1, htlc_value_satoshis, option),
188 (2, source, required),
189 (4, payment_preimage, option),
192 /// If an HTLC expires within this many blocks, don't try to claim it in a shared transaction,
193 /// instead claiming it in its own individual transaction.
194 pub(crate) const CLTV_SHARED_CLAIM_BUFFER: u32 = 12;
195 /// If an HTLC expires within this many blocks, force-close the channel to broadcast the
196 /// HTLC-Success transaction.
197 /// In other words, this is an upper bound on how many blocks we think it can take us to get a
198 /// transaction confirmed (and we use it in a few more, equivalent, places).
199 pub(crate) const CLTV_CLAIM_BUFFER: u32 = 18;
200 /// Number of blocks by which point we expect our counterparty to have seen new blocks on the
201 /// network and done a full update_fail_htlc/commitment_signed dance (+ we've updated all our
202 /// copies of ChannelMonitors, including watchtowers). We could enforce the contract by failing
203 /// at CLTV expiration height but giving a grace period to our peer may be profitable for us if he
204 /// can provide an over-late preimage. Nevertheless, grace period has to be accounted in our
205 /// CLTV_EXPIRY_DELTA to be secure. Following this policy we may decrease the rate of channel failures
206 /// due to expiration but increase the cost of funds being locked longuer in case of failure.
207 /// This delay also cover a low-power peer being slow to process blocks and so being behind us on
208 /// accurate block height.
209 /// In case of onchain failure to be pass backward we may see the last block of ANTI_REORG_DELAY
210 /// with at worst this delay, so we are not only using this value as a mercy for them but also
211 /// us as a safeguard to delay with enough time.
212 pub(crate) const LATENCY_GRACE_PERIOD_BLOCKS: u32 = 3;
213 /// Number of blocks we wait on seeing a HTLC output being solved before we fail corresponding
214 /// inbound HTLCs. This prevents us from failing backwards and then getting a reorg resulting in us
217 /// Note that this is a library-wide security assumption. If a reorg deeper than this number of
218 /// blocks occurs, counterparties may be able to steal funds or claims made by and balances exposed
219 /// by a [`ChannelMonitor`] may be incorrect.
220 // We also use this delay to be sure we can remove our in-flight claim txn from bump candidates buffer.
221 // It may cause spurious generation of bumped claim txn but that's alright given the outpoint is already
222 // solved by a previous claim tx. What we want to avoid is reorg evicting our claim tx and us not
223 // keep bumping another claim tx to solve the outpoint.
224 pub const ANTI_REORG_DELAY: u32 = 6;
225 /// Number of blocks before confirmation at which we fail back an un-relayed HTLC or at which we
226 /// refuse to accept a new HTLC.
228 /// This is used for a few separate purposes:
229 /// 1) if we've received an MPP HTLC to us and it expires within this many blocks and we are
230 /// waiting on additional parts (or waiting on the preimage for any HTLC from the user), we will
232 /// 2) if we receive an HTLC within this many blocks of its expiry (plus one to avoid a race
233 /// condition with the above), we will fail this HTLC without telling the user we received it,
235 /// (1) is all about protecting us - we need enough time to update the channel state before we hit
236 /// CLTV_CLAIM_BUFFER, at which point we'd go on chain to claim the HTLC with the preimage.
238 /// (2) is the same, but with an additional buffer to avoid accepting an HTLC which is immediately
239 /// in a race condition between the user connecting a block (which would fail it) and the user
240 /// providing us the preimage (which would claim it).
241 pub(crate) const HTLC_FAIL_BACK_BUFFER: u32 = CLTV_CLAIM_BUFFER + LATENCY_GRACE_PERIOD_BLOCKS;
243 // TODO(devrandom) replace this with HolderCommitmentTransaction
244 #[derive(Clone, PartialEq, Eq)]
245 struct HolderSignedTx {
246 /// txid of the transaction in tx, just used to make comparison faster
248 revocation_key: PublicKey,
249 a_htlc_key: PublicKey,
250 b_htlc_key: PublicKey,
251 delayed_payment_key: PublicKey,
252 per_commitment_point: PublicKey,
253 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
254 to_self_value_sat: u64,
257 impl_writeable_tlv_based!(HolderSignedTx, {
259 // Note that this is filled in with data from OnchainTxHandler if it's missing.
260 // For HolderSignedTx objects serialized with 0.0.100+, this should be filled in.
261 (1, to_self_value_sat, (default_value, u64::max_value())),
262 (2, revocation_key, required),
263 (4, a_htlc_key, required),
264 (6, b_htlc_key, required),
265 (8, delayed_payment_key, required),
266 (10, per_commitment_point, required),
267 (12, feerate_per_kw, required),
268 (14, htlc_outputs, vec_type)
272 impl HolderSignedTx {
273 fn non_dust_htlcs(&self) -> Vec<HTLCOutputInCommitment> {
274 self.htlc_outputs.iter().filter_map(|(htlc, _, _)| {
275 if let Some(_) = htlc.transaction_output_index {
285 /// We use this to track static counterparty commitment transaction data and to generate any
286 /// justice or 2nd-stage preimage/timeout transactions.
287 #[derive(PartialEq, Eq)]
288 struct CounterpartyCommitmentParameters {
289 counterparty_delayed_payment_base_key: PublicKey,
290 counterparty_htlc_base_key: PublicKey,
291 on_counterparty_tx_csv: u16,
294 impl Writeable for CounterpartyCommitmentParameters {
295 fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
296 w.write_all(&(0 as u64).to_be_bytes())?;
297 write_tlv_fields!(w, {
298 (0, self.counterparty_delayed_payment_base_key, required),
299 (2, self.counterparty_htlc_base_key, required),
300 (4, self.on_counterparty_tx_csv, required),
305 impl Readable for CounterpartyCommitmentParameters {
306 fn read<R: io::Read>(r: &mut R) -> Result<Self, DecodeError> {
307 let counterparty_commitment_transaction = {
308 // Versions prior to 0.0.100 had some per-HTLC state stored here, which is no longer
309 // used. Read it for compatibility.
310 let per_htlc_len: u64 = Readable::read(r)?;
311 for _ in 0..per_htlc_len {
312 let _txid: Txid = Readable::read(r)?;
313 let htlcs_count: u64 = Readable::read(r)?;
314 for _ in 0..htlcs_count {
315 let _htlc: HTLCOutputInCommitment = Readable::read(r)?;
319 let mut counterparty_delayed_payment_base_key = RequiredWrapper(None);
320 let mut counterparty_htlc_base_key = RequiredWrapper(None);
321 let mut on_counterparty_tx_csv: u16 = 0;
322 read_tlv_fields!(r, {
323 (0, counterparty_delayed_payment_base_key, required),
324 (2, counterparty_htlc_base_key, required),
325 (4, on_counterparty_tx_csv, required),
327 CounterpartyCommitmentParameters {
328 counterparty_delayed_payment_base_key: counterparty_delayed_payment_base_key.0.unwrap(),
329 counterparty_htlc_base_key: counterparty_htlc_base_key.0.unwrap(),
330 on_counterparty_tx_csv,
333 Ok(counterparty_commitment_transaction)
337 /// An entry for an [`OnchainEvent`], stating the block height and hash when the event was
338 /// observed, as well as the transaction causing it.
340 /// Used to determine when the on-chain event can be considered safe from a chain reorganization.
341 #[derive(PartialEq, Eq)]
342 struct OnchainEventEntry {
345 block_hash: Option<BlockHash>, // Added as optional, will be filled in for any entry generated on 0.0.113 or after
347 transaction: Option<Transaction>, // Added as optional, but always filled in, in LDK 0.0.110
350 impl OnchainEventEntry {
351 fn confirmation_threshold(&self) -> u32 {
352 let mut conf_threshold = self.height + ANTI_REORG_DELAY - 1;
354 OnchainEvent::MaturingOutput {
355 descriptor: SpendableOutputDescriptor::DelayedPaymentOutput(ref descriptor)
357 // A CSV'd transaction is confirmable in block (input height) + CSV delay, which means
358 // it's broadcastable when we see the previous block.
359 conf_threshold = cmp::max(conf_threshold, self.height + descriptor.to_self_delay as u32 - 1);
361 OnchainEvent::FundingSpendConfirmation { on_local_output_csv: Some(csv), .. } |
362 OnchainEvent::HTLCSpendConfirmation { on_to_local_output_csv: Some(csv), .. } => {
363 // A CSV'd transaction is confirmable in block (input height) + CSV delay, which means
364 // it's broadcastable when we see the previous block.
365 conf_threshold = cmp::max(conf_threshold, self.height + csv as u32 - 1);
372 fn has_reached_confirmation_threshold(&self, best_block: &BestBlock) -> bool {
373 best_block.height() >= self.confirmation_threshold()
377 /// The (output index, sats value) for the counterparty's output in a commitment transaction.
379 /// This was added as an `Option` in 0.0.110.
380 type CommitmentTxCounterpartyOutputInfo = Option<(u32, u64)>;
382 /// Upon discovering of some classes of onchain tx by ChannelMonitor, we may have to take actions on it
383 /// once they mature to enough confirmations (ANTI_REORG_DELAY)
384 #[derive(PartialEq, Eq)]
386 /// An outbound HTLC failing after a transaction is confirmed. Used
387 /// * when an outbound HTLC output is spent by us after the HTLC timed out
388 /// * an outbound HTLC which was not present in the commitment transaction which appeared
389 /// on-chain (either because it was not fully committed to or it was dust).
390 /// Note that this is *not* used for preimage claims, as those are passed upstream immediately,
391 /// appearing only as an `HTLCSpendConfirmation`, below.
394 payment_hash: PaymentHash,
395 htlc_value_satoshis: Option<u64>,
396 /// None in the second case, above, ie when there is no relevant output in the commitment
397 /// transaction which appeared on chain.
398 commitment_tx_output_idx: Option<u32>,
400 /// An output waiting on [`ANTI_REORG_DELAY`] confirmations before we hand the user the
401 /// [`SpendableOutputDescriptor`].
403 descriptor: SpendableOutputDescriptor,
405 /// A spend of the funding output, either a commitment transaction or a cooperative closing
407 FundingSpendConfirmation {
408 /// The CSV delay for the output of the funding spend transaction (implying it is a local
409 /// commitment transaction, and this is the delay on the to_self output).
410 on_local_output_csv: Option<u16>,
411 /// If the funding spend transaction was a known remote commitment transaction, we track
412 /// the output index and amount of the counterparty's `to_self` output here.
414 /// This allows us to generate a [`Balance::CounterpartyRevokedOutputClaimable`] for the
415 /// counterparty output.
416 commitment_tx_to_counterparty_output: CommitmentTxCounterpartyOutputInfo,
418 /// A spend of a commitment transaction HTLC output, set in the cases where *no* `HTLCUpdate`
419 /// is constructed. This is used when
420 /// * an outbound HTLC is claimed by our counterparty with a preimage, causing us to
421 /// immediately claim the HTLC on the inbound edge and track the resolution here,
422 /// * an inbound HTLC is claimed by our counterparty (with a timeout),
423 /// * an inbound HTLC is claimed by us (with a preimage).
424 /// * a revoked-state HTLC transaction was broadcasted, which was claimed by the revocation
426 /// * a revoked-state HTLC transaction was broadcasted, which was claimed by an
427 /// HTLC-Success/HTLC-Failure transaction (and is still claimable with a revocation
429 HTLCSpendConfirmation {
430 commitment_tx_output_idx: u32,
431 /// If the claim was made by either party with a preimage, this is filled in
432 preimage: Option<PaymentPreimage>,
433 /// If the claim was made by us on an inbound HTLC against a local commitment transaction,
434 /// we set this to the output CSV value which we will have to wait until to spend the
435 /// output (and generate a SpendableOutput event).
436 on_to_local_output_csv: Option<u16>,
440 impl Writeable for OnchainEventEntry {
441 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
442 write_tlv_fields!(writer, {
443 (0, self.txid, required),
444 (1, self.transaction, option),
445 (2, self.height, required),
446 (3, self.block_hash, option),
447 (4, self.event, required),
453 impl MaybeReadable for OnchainEventEntry {
454 fn read<R: io::Read>(reader: &mut R) -> Result<Option<Self>, DecodeError> {
455 let mut txid = Txid::all_zeros();
456 let mut transaction = None;
457 let mut block_hash = None;
459 let mut event = UpgradableRequired(None);
460 read_tlv_fields!(reader, {
462 (1, transaction, option),
463 (2, height, required),
464 (3, block_hash, option),
465 (4, event, upgradable_required),
467 Ok(Some(Self { txid, transaction, height, block_hash, event: _init_tlv_based_struct_field!(event, upgradable_required) }))
471 impl_writeable_tlv_based_enum_upgradable!(OnchainEvent,
473 (0, source, required),
474 (1, htlc_value_satoshis, option),
475 (2, payment_hash, required),
476 (3, commitment_tx_output_idx, option),
478 (1, MaturingOutput) => {
479 (0, descriptor, required),
481 (3, FundingSpendConfirmation) => {
482 (0, on_local_output_csv, option),
483 (1, commitment_tx_to_counterparty_output, option),
485 (5, HTLCSpendConfirmation) => {
486 (0, commitment_tx_output_idx, required),
487 (2, preimage, option),
488 (4, on_to_local_output_csv, option),
493 #[derive(Clone, PartialEq, Eq)]
494 pub(crate) enum ChannelMonitorUpdateStep {
495 LatestHolderCommitmentTXInfo {
496 commitment_tx: HolderCommitmentTransaction,
497 /// Note that LDK after 0.0.115 supports this only containing dust HTLCs (implying the
498 /// `Signature` field is never filled in). At that point, non-dust HTLCs are implied by the
499 /// HTLC fields in `commitment_tx` and the sources passed via `nondust_htlc_sources`.
500 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
501 claimed_htlcs: Vec<(SentHTLCId, PaymentPreimage)>,
502 nondust_htlc_sources: Vec<HTLCSource>,
504 LatestCounterpartyCommitmentTXInfo {
505 commitment_txid: Txid,
506 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
507 commitment_number: u64,
508 their_per_commitment_point: PublicKey,
511 payment_preimage: PaymentPreimage,
517 /// Used to indicate that the no future updates will occur, and likely that the latest holder
518 /// commitment transaction(s) should be broadcast, as the channel has been force-closed.
520 /// If set to false, we shouldn't broadcast the latest holder commitment transaction as we
521 /// think we've fallen behind!
522 should_broadcast: bool,
525 scriptpubkey: Script,
529 impl ChannelMonitorUpdateStep {
530 fn variant_name(&self) -> &'static str {
532 ChannelMonitorUpdateStep::LatestHolderCommitmentTXInfo { .. } => "LatestHolderCommitmentTXInfo",
533 ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo { .. } => "LatestCounterpartyCommitmentTXInfo",
534 ChannelMonitorUpdateStep::PaymentPreimage { .. } => "PaymentPreimage",
535 ChannelMonitorUpdateStep::CommitmentSecret { .. } => "CommitmentSecret",
536 ChannelMonitorUpdateStep::ChannelForceClosed { .. } => "ChannelForceClosed",
537 ChannelMonitorUpdateStep::ShutdownScript { .. } => "ShutdownScript",
542 impl_writeable_tlv_based_enum_upgradable!(ChannelMonitorUpdateStep,
543 (0, LatestHolderCommitmentTXInfo) => {
544 (0, commitment_tx, required),
545 (1, claimed_htlcs, vec_type),
546 (2, htlc_outputs, vec_type),
547 (4, nondust_htlc_sources, optional_vec),
549 (1, LatestCounterpartyCommitmentTXInfo) => {
550 (0, commitment_txid, required),
551 (2, commitment_number, required),
552 (4, their_per_commitment_point, required),
553 (6, htlc_outputs, vec_type),
555 (2, PaymentPreimage) => {
556 (0, payment_preimage, required),
558 (3, CommitmentSecret) => {
560 (2, secret, required),
562 (4, ChannelForceClosed) => {
563 (0, should_broadcast, required),
565 (5, ShutdownScript) => {
566 (0, scriptpubkey, required),
570 /// Details about the balance(s) available for spending once the channel appears on chain.
572 /// See [`ChannelMonitor::get_claimable_balances`] for more details on when these will or will not
574 #[derive(Clone, Debug, PartialEq, Eq)]
575 #[cfg_attr(test, derive(PartialOrd, Ord))]
577 /// The channel is not yet closed (or the commitment or closing transaction has not yet
578 /// appeared in a block). The given balance is claimable (less on-chain fees) if the channel is
579 /// force-closed now.
580 ClaimableOnChannelClose {
581 /// The amount available to claim, in satoshis, excluding the on-chain fees which will be
582 /// required to do so.
583 claimable_amount_satoshis: u64,
585 /// The channel has been closed, and the given balance is ours but awaiting confirmations until
586 /// we consider it spendable.
587 ClaimableAwaitingConfirmations {
588 /// The amount available to claim, in satoshis, possibly excluding the on-chain fees which
589 /// were spent in broadcasting the transaction.
590 claimable_amount_satoshis: u64,
591 /// The height at which an [`Event::SpendableOutputs`] event will be generated for this
593 confirmation_height: u32,
595 /// The channel has been closed, and the given balance should be ours but awaiting spending
596 /// transaction confirmation. If the spending transaction does not confirm in time, it is
597 /// possible our counterparty can take the funds by broadcasting an HTLC timeout on-chain.
599 /// Once the spending transaction confirms, before it has reached enough confirmations to be
600 /// considered safe from chain reorganizations, the balance will instead be provided via
601 /// [`Balance::ClaimableAwaitingConfirmations`].
602 ContentiousClaimable {
603 /// The amount available to claim, in satoshis, excluding the on-chain fees which will be
604 /// required to do so.
605 claimable_amount_satoshis: u64,
606 /// The height at which the counterparty may be able to claim the balance if we have not
609 /// The payment hash that locks this HTLC.
610 payment_hash: PaymentHash,
611 /// The preimage that can be used to claim this HTLC.
612 payment_preimage: PaymentPreimage,
614 /// HTLCs which we sent to our counterparty which are claimable after a timeout (less on-chain
615 /// fees) if the counterparty does not know the preimage for the HTLCs. These are somewhat
616 /// likely to be claimed by our counterparty before we do.
617 MaybeTimeoutClaimableHTLC {
618 /// The amount potentially available to claim, in satoshis, excluding the on-chain fees
619 /// which will be required to do so.
620 claimable_amount_satoshis: u64,
621 /// The height at which we will be able to claim the balance if our counterparty has not
623 claimable_height: u32,
624 /// The payment hash whose preimage our counterparty needs to claim this HTLC.
625 payment_hash: PaymentHash,
627 /// HTLCs which we received from our counterparty which are claimable with a preimage which we
628 /// do not currently have. This will only be claimable if we receive the preimage from the node
629 /// to which we forwarded this HTLC before the timeout.
630 MaybePreimageClaimableHTLC {
631 /// The amount potentially available to claim, in satoshis, excluding the on-chain fees
632 /// which will be required to do so.
633 claimable_amount_satoshis: u64,
634 /// The height at which our counterparty will be able to claim the balance if we have not
635 /// yet received the preimage and claimed it ourselves.
637 /// The payment hash whose preimage we need to claim this HTLC.
638 payment_hash: PaymentHash,
640 /// The channel has been closed, and our counterparty broadcasted a revoked commitment
643 /// Thus, we're able to claim all outputs in the commitment transaction, one of which has the
644 /// following amount.
645 CounterpartyRevokedOutputClaimable {
646 /// The amount, in satoshis, of the output which we can claim.
648 /// Note that for outputs from HTLC balances this may be excluding some on-chain fees that
649 /// were already spent.
650 claimable_amount_satoshis: u64,
655 /// The amount claimable, in satoshis. This excludes balances that we are unsure if we are able
656 /// to claim, this is because we are waiting for a preimage or for a timeout to expire. For more
657 /// information on these balances see [`Balance::MaybeTimeoutClaimableHTLC`] and
658 /// [`Balance::MaybePreimageClaimableHTLC`].
660 /// On-chain fees required to claim the balance are not included in this amount.
661 pub fn claimable_amount_satoshis(&self) -> u64 {
663 Balance::ClaimableOnChannelClose {
664 claimable_amount_satoshis,
665 } => *claimable_amount_satoshis,
666 Balance::ClaimableAwaitingConfirmations {
667 claimable_amount_satoshis,
669 } => *claimable_amount_satoshis,
670 Balance::ContentiousClaimable {
671 claimable_amount_satoshis,
673 } => *claimable_amount_satoshis,
674 Balance::MaybeTimeoutClaimableHTLC {
677 Balance::MaybePreimageClaimableHTLC {
680 Balance::CounterpartyRevokedOutputClaimable {
681 claimable_amount_satoshis,
683 } => *claimable_amount_satoshis,
688 /// An HTLC which has been irrevocably resolved on-chain, and has reached ANTI_REORG_DELAY.
689 #[derive(PartialEq, Eq)]
690 struct IrrevocablyResolvedHTLC {
691 commitment_tx_output_idx: Option<u32>,
692 /// The txid of the transaction which resolved the HTLC, this may be a commitment (if the HTLC
693 /// was not present in the confirmed commitment transaction), HTLC-Success, or HTLC-Timeout
695 resolving_txid: Option<Txid>, // Added as optional, but always filled in, in 0.0.110
696 resolving_tx: Option<Transaction>,
697 /// Only set if the HTLC claim was ours using a payment preimage
698 payment_preimage: Option<PaymentPreimage>,
701 // In LDK versions prior to 0.0.111 commitment_tx_output_idx was not Option-al and
702 // IrrevocablyResolvedHTLC objects only existed for non-dust HTLCs. This was a bug, but to maintain
703 // backwards compatibility we must ensure we always write out a commitment_tx_output_idx field,
704 // using `u32::max_value()` as a sentinal to indicate the HTLC was dust.
705 impl Writeable for IrrevocablyResolvedHTLC {
706 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
707 let mapped_commitment_tx_output_idx = self.commitment_tx_output_idx.unwrap_or(u32::max_value());
708 write_tlv_fields!(writer, {
709 (0, mapped_commitment_tx_output_idx, required),
710 (1, self.resolving_txid, option),
711 (2, self.payment_preimage, option),
712 (3, self.resolving_tx, option),
718 impl Readable for IrrevocablyResolvedHTLC {
719 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
720 let mut mapped_commitment_tx_output_idx = 0;
721 let mut resolving_txid = None;
722 let mut payment_preimage = None;
723 let mut resolving_tx = None;
724 read_tlv_fields!(reader, {
725 (0, mapped_commitment_tx_output_idx, required),
726 (1, resolving_txid, option),
727 (2, payment_preimage, option),
728 (3, resolving_tx, option),
731 commitment_tx_output_idx: if mapped_commitment_tx_output_idx == u32::max_value() { None } else { Some(mapped_commitment_tx_output_idx) },
739 /// A ChannelMonitor handles chain events (blocks connected and disconnected) and generates
740 /// on-chain transactions to ensure no loss of funds occurs.
742 /// You MUST ensure that no ChannelMonitors for a given channel anywhere contain out-of-date
743 /// information and are actively monitoring the chain.
745 /// Pending Events or updated HTLCs which have not yet been read out by
746 /// get_and_clear_pending_monitor_events or get_and_clear_pending_events are serialized to disk and
747 /// reloaded at deserialize-time. Thus, you must ensure that, when handling events, all events
748 /// gotten are fully handled before re-serializing the new state.
750 /// Note that the deserializer is only implemented for (BlockHash, ChannelMonitor), which
751 /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
752 /// the "reorg path" (ie disconnecting blocks until you find a common ancestor from both the
753 /// returned block hash and the the current chain and then reconnecting blocks to get to the
754 /// best chain) upon deserializing the object!
755 pub struct ChannelMonitor<Signer: WriteableEcdsaChannelSigner> {
757 pub(crate) inner: Mutex<ChannelMonitorImpl<Signer>>,
759 inner: Mutex<ChannelMonitorImpl<Signer>>,
763 pub(crate) struct ChannelMonitorImpl<Signer: WriteableEcdsaChannelSigner> {
764 latest_update_id: u64,
765 commitment_transaction_number_obscure_factor: u64,
767 destination_script: Script,
768 broadcasted_holder_revokable_script: Option<(Script, PublicKey, PublicKey)>,
769 counterparty_payment_script: Script,
770 shutdown_script: Option<Script>,
772 channel_keys_id: [u8; 32],
773 holder_revocation_basepoint: PublicKey,
774 funding_info: (OutPoint, Script),
775 current_counterparty_commitment_txid: Option<Txid>,
776 prev_counterparty_commitment_txid: Option<Txid>,
778 counterparty_commitment_params: CounterpartyCommitmentParameters,
779 funding_redeemscript: Script,
780 channel_value_satoshis: u64,
781 // first is the idx of the first of the two per-commitment points
782 their_cur_per_commitment_points: Option<(u64, PublicKey, Option<PublicKey>)>,
784 on_holder_tx_csv: u16,
786 commitment_secrets: CounterpartyCommitmentSecrets,
787 /// The set of outpoints in each counterparty commitment transaction. We always need at least
788 /// the payment hash from `HTLCOutputInCommitment` to claim even a revoked commitment
789 /// transaction broadcast as we need to be able to construct the witness script in all cases.
790 counterparty_claimable_outpoints: HashMap<Txid, Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>>,
791 /// We cannot identify HTLC-Success or HTLC-Timeout transactions by themselves on the chain.
792 /// Nor can we figure out their commitment numbers without the commitment transaction they are
793 /// spending. Thus, in order to claim them via revocation key, we track all the counterparty
794 /// commitment transactions which we find on-chain, mapping them to the commitment number which
795 /// can be used to derive the revocation key and claim the transactions.
796 counterparty_commitment_txn_on_chain: HashMap<Txid, u64>,
797 /// Cache used to make pruning of payment_preimages faster.
798 /// Maps payment_hash values to commitment numbers for counterparty transactions for non-revoked
799 /// counterparty transactions (ie should remain pretty small).
800 /// Serialized to disk but should generally not be sent to Watchtowers.
801 counterparty_hash_commitment_number: HashMap<PaymentHash, u64>,
803 counterparty_fulfilled_htlcs: HashMap<SentHTLCId, PaymentPreimage>,
805 // We store two holder commitment transactions to avoid any race conditions where we may update
806 // some monitors (potentially on watchtowers) but then fail to update others, resulting in the
807 // various monitors for one channel being out of sync, and us broadcasting a holder
808 // transaction for which we have deleted claim information on some watchtowers.
809 prev_holder_signed_commitment_tx: Option<HolderSignedTx>,
810 current_holder_commitment_tx: HolderSignedTx,
812 // Used just for ChannelManager to make sure it has the latest channel data during
814 current_counterparty_commitment_number: u64,
815 // Used just for ChannelManager to make sure it has the latest channel data during
817 current_holder_commitment_number: u64,
819 /// The set of payment hashes from inbound payments for which we know the preimage. Payment
820 /// preimages that are not included in any unrevoked local commitment transaction or unrevoked
821 /// remote commitment transactions are automatically removed when commitment transactions are
823 payment_preimages: HashMap<PaymentHash, PaymentPreimage>,
825 // Note that `MonitorEvent`s MUST NOT be generated during update processing, only generated
826 // during chain data processing. This prevents a race in `ChainMonitor::update_channel` (and
827 // presumably user implementations thereof as well) where we update the in-memory channel
828 // object, then before the persistence finishes (as it's all under a read-lock), we return
829 // pending events to the user or to the relevant `ChannelManager`. Then, on reload, we'll have
830 // the pre-event state here, but have processed the event in the `ChannelManager`.
831 // Note that because the `event_lock` in `ChainMonitor` is only taken in
832 // block/transaction-connected events and *not* during block/transaction-disconnected events,
833 // we further MUST NOT generate events during block/transaction-disconnection.
834 pending_monitor_events: Vec<MonitorEvent>,
836 pending_events: Vec<Event>,
838 // Used to track on-chain events (i.e., transactions part of channels confirmed on chain) on
839 // which to take actions once they reach enough confirmations. Each entry includes the
840 // transaction's id and the height when the transaction was confirmed on chain.
841 onchain_events_awaiting_threshold_conf: Vec<OnchainEventEntry>,
843 // If we get serialized out and re-read, we need to make sure that the chain monitoring
844 // interface knows about the TXOs that we want to be notified of spends of. We could probably
845 // be smart and derive them from the above storage fields, but its much simpler and more
846 // Obviously Correct (tm) if we just keep track of them explicitly.
847 outputs_to_watch: HashMap<Txid, Vec<(u32, Script)>>,
850 pub onchain_tx_handler: OnchainTxHandler<Signer>,
852 onchain_tx_handler: OnchainTxHandler<Signer>,
854 // This is set when the Channel[Manager] generated a ChannelMonitorUpdate which indicated the
855 // channel has been force-closed. After this is set, no further holder commitment transaction
856 // updates may occur, and we panic!() if one is provided.
857 lockdown_from_offchain: bool,
859 // Set once we've signed a holder commitment transaction and handed it over to our
860 // OnchainTxHandler. After this is set, no future updates to our holder commitment transactions
861 // may occur, and we fail any such monitor updates.
863 // In case of update rejection due to a locally already signed commitment transaction, we
864 // nevertheless store update content to track in case of concurrent broadcast by another
865 // remote monitor out-of-order with regards to the block view.
866 holder_tx_signed: bool,
868 // If a spend of the funding output is seen, we set this to true and reject any further
869 // updates. This prevents any further changes in the offchain state no matter the order
870 // of block connection between ChannelMonitors and the ChannelManager.
871 funding_spend_seen: bool,
873 /// Set to `Some` of the confirmed transaction spending the funding input of the channel after
874 /// reaching `ANTI_REORG_DELAY` confirmations.
875 funding_spend_confirmed: Option<Txid>,
877 confirmed_commitment_tx_counterparty_output: CommitmentTxCounterpartyOutputInfo,
878 /// The set of HTLCs which have been either claimed or failed on chain and have reached
879 /// the requisite confirmations on the claim/fail transaction (either ANTI_REORG_DELAY or the
880 /// spending CSV for revocable outputs).
881 htlcs_resolved_on_chain: Vec<IrrevocablyResolvedHTLC>,
883 /// The set of `SpendableOutput` events which we have already passed upstream to be claimed.
884 /// These are tracked explicitly to ensure that we don't generate the same events redundantly
885 /// if users duplicatively confirm old transactions. Specifically for transactions claiming a
886 /// revoked remote outpoint we otherwise have no tracking at all once they've reached
887 /// [`ANTI_REORG_DELAY`], so we have to track them here.
888 spendable_txids_confirmed: Vec<Txid>,
890 // We simply modify best_block in Channel's block_connected so that serialization is
891 // consistent but hopefully the users' copy handles block_connected in a consistent way.
892 // (we do *not*, however, update them in update_monitor to ensure any local user copies keep
893 // their best_block from its state and not based on updated copies that didn't run through
894 // the full block_connected).
895 best_block: BestBlock,
897 /// The node_id of our counterparty
898 counterparty_node_id: Option<PublicKey>,
901 /// Transaction outputs to watch for on-chain spends.
902 pub type TransactionOutputs = (Txid, Vec<(u32, TxOut)>);
904 impl<Signer: WriteableEcdsaChannelSigner> PartialEq for ChannelMonitor<Signer> where Signer: PartialEq {
905 fn eq(&self, other: &Self) -> bool {
906 // We need some kind of total lockorder. Absent a better idea, we sort by position in
907 // memory and take locks in that order (assuming that we can't move within memory while a
909 let ord = ((self as *const _) as usize) < ((other as *const _) as usize);
910 let a = if ord { self.inner.unsafe_well_ordered_double_lock_self() } else { other.inner.unsafe_well_ordered_double_lock_self() };
911 let b = if ord { other.inner.unsafe_well_ordered_double_lock_self() } else { self.inner.unsafe_well_ordered_double_lock_self() };
916 impl<Signer: WriteableEcdsaChannelSigner> Writeable for ChannelMonitor<Signer> {
917 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), Error> {
918 self.inner.lock().unwrap().write(writer)
922 // These are also used for ChannelMonitorUpdate, above.
923 const SERIALIZATION_VERSION: u8 = 1;
924 const MIN_SERIALIZATION_VERSION: u8 = 1;
926 impl<Signer: WriteableEcdsaChannelSigner> Writeable for ChannelMonitorImpl<Signer> {
927 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), Error> {
928 write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
930 self.latest_update_id.write(writer)?;
932 // Set in initial Channel-object creation, so should always be set by now:
933 U48(self.commitment_transaction_number_obscure_factor).write(writer)?;
935 self.destination_script.write(writer)?;
936 if let Some(ref broadcasted_holder_revokable_script) = self.broadcasted_holder_revokable_script {
937 writer.write_all(&[0; 1])?;
938 broadcasted_holder_revokable_script.0.write(writer)?;
939 broadcasted_holder_revokable_script.1.write(writer)?;
940 broadcasted_holder_revokable_script.2.write(writer)?;
942 writer.write_all(&[1; 1])?;
945 self.counterparty_payment_script.write(writer)?;
946 match &self.shutdown_script {
947 Some(script) => script.write(writer)?,
948 None => Script::new().write(writer)?,
951 self.channel_keys_id.write(writer)?;
952 self.holder_revocation_basepoint.write(writer)?;
953 writer.write_all(&self.funding_info.0.txid[..])?;
954 writer.write_all(&self.funding_info.0.index.to_be_bytes())?;
955 self.funding_info.1.write(writer)?;
956 self.current_counterparty_commitment_txid.write(writer)?;
957 self.prev_counterparty_commitment_txid.write(writer)?;
959 self.counterparty_commitment_params.write(writer)?;
960 self.funding_redeemscript.write(writer)?;
961 self.channel_value_satoshis.write(writer)?;
963 match self.their_cur_per_commitment_points {
964 Some((idx, pubkey, second_option)) => {
965 writer.write_all(&byte_utils::be48_to_array(idx))?;
966 writer.write_all(&pubkey.serialize())?;
967 match second_option {
968 Some(second_pubkey) => {
969 writer.write_all(&second_pubkey.serialize())?;
972 writer.write_all(&[0; 33])?;
977 writer.write_all(&byte_utils::be48_to_array(0))?;
981 writer.write_all(&self.on_holder_tx_csv.to_be_bytes())?;
983 self.commitment_secrets.write(writer)?;
985 macro_rules! serialize_htlc_in_commitment {
986 ($htlc_output: expr) => {
987 writer.write_all(&[$htlc_output.offered as u8; 1])?;
988 writer.write_all(&$htlc_output.amount_msat.to_be_bytes())?;
989 writer.write_all(&$htlc_output.cltv_expiry.to_be_bytes())?;
990 writer.write_all(&$htlc_output.payment_hash.0[..])?;
991 $htlc_output.transaction_output_index.write(writer)?;
995 writer.write_all(&(self.counterparty_claimable_outpoints.len() as u64).to_be_bytes())?;
996 for (ref txid, ref htlc_infos) in self.counterparty_claimable_outpoints.iter() {
997 writer.write_all(&txid[..])?;
998 writer.write_all(&(htlc_infos.len() as u64).to_be_bytes())?;
999 for &(ref htlc_output, ref htlc_source) in htlc_infos.iter() {
1000 debug_assert!(htlc_source.is_none() || Some(**txid) == self.current_counterparty_commitment_txid
1001 || Some(**txid) == self.prev_counterparty_commitment_txid,
1002 "HTLC Sources for all revoked commitment transactions should be none!");
1003 serialize_htlc_in_commitment!(htlc_output);
1004 htlc_source.as_ref().map(|b| b.as_ref()).write(writer)?;
1008 writer.write_all(&(self.counterparty_commitment_txn_on_chain.len() as u64).to_be_bytes())?;
1009 for (ref txid, commitment_number) in self.counterparty_commitment_txn_on_chain.iter() {
1010 writer.write_all(&txid[..])?;
1011 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
1014 writer.write_all(&(self.counterparty_hash_commitment_number.len() as u64).to_be_bytes())?;
1015 for (ref payment_hash, commitment_number) in self.counterparty_hash_commitment_number.iter() {
1016 writer.write_all(&payment_hash.0[..])?;
1017 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
1020 if let Some(ref prev_holder_tx) = self.prev_holder_signed_commitment_tx {
1021 writer.write_all(&[1; 1])?;
1022 prev_holder_tx.write(writer)?;
1024 writer.write_all(&[0; 1])?;
1027 self.current_holder_commitment_tx.write(writer)?;
1029 writer.write_all(&byte_utils::be48_to_array(self.current_counterparty_commitment_number))?;
1030 writer.write_all(&byte_utils::be48_to_array(self.current_holder_commitment_number))?;
1032 writer.write_all(&(self.payment_preimages.len() as u64).to_be_bytes())?;
1033 for payment_preimage in self.payment_preimages.values() {
1034 writer.write_all(&payment_preimage.0[..])?;
1037 writer.write_all(&(self.pending_monitor_events.iter().filter(|ev| match ev {
1038 MonitorEvent::HTLCEvent(_) => true,
1039 MonitorEvent::CommitmentTxConfirmed(_) => true,
1041 }).count() as u64).to_be_bytes())?;
1042 for event in self.pending_monitor_events.iter() {
1044 MonitorEvent::HTLCEvent(upd) => {
1048 MonitorEvent::CommitmentTxConfirmed(_) => 1u8.write(writer)?,
1049 _ => {}, // Covered in the TLV writes below
1053 writer.write_all(&(self.pending_events.len() as u64).to_be_bytes())?;
1054 for event in self.pending_events.iter() {
1055 event.write(writer)?;
1058 self.best_block.block_hash().write(writer)?;
1059 writer.write_all(&self.best_block.height().to_be_bytes())?;
1061 writer.write_all(&(self.onchain_events_awaiting_threshold_conf.len() as u64).to_be_bytes())?;
1062 for ref entry in self.onchain_events_awaiting_threshold_conf.iter() {
1063 entry.write(writer)?;
1066 (self.outputs_to_watch.len() as u64).write(writer)?;
1067 for (txid, idx_scripts) in self.outputs_to_watch.iter() {
1068 txid.write(writer)?;
1069 (idx_scripts.len() as u64).write(writer)?;
1070 for (idx, script) in idx_scripts.iter() {
1072 script.write(writer)?;
1075 self.onchain_tx_handler.write(writer)?;
1077 self.lockdown_from_offchain.write(writer)?;
1078 self.holder_tx_signed.write(writer)?;
1080 write_tlv_fields!(writer, {
1081 (1, self.funding_spend_confirmed, option),
1082 (3, self.htlcs_resolved_on_chain, vec_type),
1083 (5, self.pending_monitor_events, vec_type),
1084 (7, self.funding_spend_seen, required),
1085 (9, self.counterparty_node_id, option),
1086 (11, self.confirmed_commitment_tx_counterparty_output, option),
1087 (13, self.spendable_txids_confirmed, vec_type),
1088 (15, self.counterparty_fulfilled_htlcs, required),
1095 impl<Signer: WriteableEcdsaChannelSigner> ChannelMonitor<Signer> {
1096 /// For lockorder enforcement purposes, we need to have a single site which constructs the
1097 /// `inner` mutex, otherwise cases where we lock two monitors at the same time (eg in our
1098 /// PartialEq implementation) we may decide a lockorder violation has occurred.
1099 fn from_impl(imp: ChannelMonitorImpl<Signer>) -> Self {
1100 ChannelMonitor { inner: Mutex::new(imp) }
1103 pub(crate) fn new(secp_ctx: Secp256k1<secp256k1::All>, keys: Signer, shutdown_script: Option<Script>,
1104 on_counterparty_tx_csv: u16, destination_script: &Script, funding_info: (OutPoint, Script),
1105 channel_parameters: &ChannelTransactionParameters,
1106 funding_redeemscript: Script, channel_value_satoshis: u64,
1107 commitment_transaction_number_obscure_factor: u64,
1108 initial_holder_commitment_tx: HolderCommitmentTransaction,
1109 best_block: BestBlock, counterparty_node_id: PublicKey) -> ChannelMonitor<Signer> {
1111 assert!(commitment_transaction_number_obscure_factor <= (1 << 48));
1112 let payment_key_hash = WPubkeyHash::hash(&keys.pubkeys().payment_point.serialize());
1113 let counterparty_payment_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&payment_key_hash[..]).into_script();
1115 let counterparty_channel_parameters = channel_parameters.counterparty_parameters.as_ref().unwrap();
1116 let counterparty_delayed_payment_base_key = counterparty_channel_parameters.pubkeys.delayed_payment_basepoint;
1117 let counterparty_htlc_base_key = counterparty_channel_parameters.pubkeys.htlc_basepoint;
1118 let counterparty_commitment_params = CounterpartyCommitmentParameters { counterparty_delayed_payment_base_key, counterparty_htlc_base_key, on_counterparty_tx_csv };
1120 let channel_keys_id = keys.channel_keys_id();
1121 let holder_revocation_basepoint = keys.pubkeys().revocation_basepoint;
1123 // block for Rust 1.34 compat
1124 let (holder_commitment_tx, current_holder_commitment_number) = {
1125 let trusted_tx = initial_holder_commitment_tx.trust();
1126 let txid = trusted_tx.txid();
1128 let tx_keys = trusted_tx.keys();
1129 let holder_commitment_tx = HolderSignedTx {
1131 revocation_key: tx_keys.revocation_key,
1132 a_htlc_key: tx_keys.broadcaster_htlc_key,
1133 b_htlc_key: tx_keys.countersignatory_htlc_key,
1134 delayed_payment_key: tx_keys.broadcaster_delayed_payment_key,
1135 per_commitment_point: tx_keys.per_commitment_point,
1136 htlc_outputs: Vec::new(), // There are never any HTLCs in the initial commitment transactions
1137 to_self_value_sat: initial_holder_commitment_tx.to_broadcaster_value_sat(),
1138 feerate_per_kw: trusted_tx.feerate_per_kw(),
1140 (holder_commitment_tx, trusted_tx.commitment_number())
1143 let onchain_tx_handler =
1144 OnchainTxHandler::new(destination_script.clone(), keys,
1145 channel_parameters.clone(), initial_holder_commitment_tx, secp_ctx);
1147 let mut outputs_to_watch = HashMap::new();
1148 outputs_to_watch.insert(funding_info.0.txid, vec![(funding_info.0.index as u32, funding_info.1.clone())]);
1150 Self::from_impl(ChannelMonitorImpl {
1151 latest_update_id: 0,
1152 commitment_transaction_number_obscure_factor,
1154 destination_script: destination_script.clone(),
1155 broadcasted_holder_revokable_script: None,
1156 counterparty_payment_script,
1160 holder_revocation_basepoint,
1162 current_counterparty_commitment_txid: None,
1163 prev_counterparty_commitment_txid: None,
1165 counterparty_commitment_params,
1166 funding_redeemscript,
1167 channel_value_satoshis,
1168 their_cur_per_commitment_points: None,
1170 on_holder_tx_csv: counterparty_channel_parameters.selected_contest_delay,
1172 commitment_secrets: CounterpartyCommitmentSecrets::new(),
1173 counterparty_claimable_outpoints: HashMap::new(),
1174 counterparty_commitment_txn_on_chain: HashMap::new(),
1175 counterparty_hash_commitment_number: HashMap::new(),
1176 counterparty_fulfilled_htlcs: HashMap::new(),
1178 prev_holder_signed_commitment_tx: None,
1179 current_holder_commitment_tx: holder_commitment_tx,
1180 current_counterparty_commitment_number: 1 << 48,
1181 current_holder_commitment_number,
1183 payment_preimages: HashMap::new(),
1184 pending_monitor_events: Vec::new(),
1185 pending_events: Vec::new(),
1187 onchain_events_awaiting_threshold_conf: Vec::new(),
1192 lockdown_from_offchain: false,
1193 holder_tx_signed: false,
1194 funding_spend_seen: false,
1195 funding_spend_confirmed: None,
1196 confirmed_commitment_tx_counterparty_output: None,
1197 htlcs_resolved_on_chain: Vec::new(),
1198 spendable_txids_confirmed: Vec::new(),
1201 counterparty_node_id: Some(counterparty_node_id),
1206 fn provide_secret(&self, idx: u64, secret: [u8; 32]) -> Result<(), &'static str> {
1207 self.inner.lock().unwrap().provide_secret(idx, secret)
1210 /// Informs this monitor of the latest counterparty (ie non-broadcastable) commitment transaction.
1211 /// The monitor watches for it to be broadcasted and then uses the HTLC information (and
1212 /// possibly future revocation/preimage information) to claim outputs where possible.
1213 /// We cache also the mapping hash:commitment number to lighten pruning of old preimages by watchtowers.
1214 pub(crate) fn provide_latest_counterparty_commitment_tx<L: Deref>(
1217 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
1218 commitment_number: u64,
1219 their_per_commitment_point: PublicKey,
1221 ) where L::Target: Logger {
1222 self.inner.lock().unwrap().provide_latest_counterparty_commitment_tx(
1223 txid, htlc_outputs, commitment_number, their_per_commitment_point, logger)
1227 fn provide_latest_holder_commitment_tx(
1228 &self, holder_commitment_tx: HolderCommitmentTransaction,
1229 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
1230 ) -> Result<(), ()> {
1231 self.inner.lock().unwrap().provide_latest_holder_commitment_tx(holder_commitment_tx, htlc_outputs, &Vec::new(), Vec::new()).map_err(|_| ())
1234 /// This is used to provide payment preimage(s) out-of-band during startup without updating the
1235 /// off-chain state with a new commitment transaction.
1236 pub(crate) fn provide_payment_preimage<B: Deref, F: Deref, L: Deref>(
1238 payment_hash: &PaymentHash,
1239 payment_preimage: &PaymentPreimage,
1241 fee_estimator: &LowerBoundedFeeEstimator<F>,
1244 B::Target: BroadcasterInterface,
1245 F::Target: FeeEstimator,
1248 self.inner.lock().unwrap().provide_payment_preimage(
1249 payment_hash, payment_preimage, broadcaster, fee_estimator, logger)
1252 /// Updates a ChannelMonitor on the basis of some new information provided by the Channel
1255 /// panics if the given update is not the next update by update_id.
1256 pub fn update_monitor<B: Deref, F: Deref, L: Deref>(
1258 updates: &ChannelMonitorUpdate,
1264 B::Target: BroadcasterInterface,
1265 F::Target: FeeEstimator,
1268 self.inner.lock().unwrap().update_monitor(updates, broadcaster, fee_estimator, logger)
1271 /// Gets the update_id from the latest ChannelMonitorUpdate which was applied to this
1273 pub fn get_latest_update_id(&self) -> u64 {
1274 self.inner.lock().unwrap().get_latest_update_id()
1277 /// Gets the funding transaction outpoint of the channel this ChannelMonitor is monitoring for.
1278 pub fn get_funding_txo(&self) -> (OutPoint, Script) {
1279 self.inner.lock().unwrap().get_funding_txo().clone()
1282 /// Gets a list of txids, with their output scripts (in the order they appear in the
1283 /// transaction), which we must learn about spends of via block_connected().
1284 pub fn get_outputs_to_watch(&self) -> Vec<(Txid, Vec<(u32, Script)>)> {
1285 self.inner.lock().unwrap().get_outputs_to_watch()
1286 .iter().map(|(txid, outputs)| (*txid, outputs.clone())).collect()
1289 /// Loads the funding txo and outputs to watch into the given `chain::Filter` by repeatedly
1290 /// calling `chain::Filter::register_output` and `chain::Filter::register_tx` until all outputs
1291 /// have been registered.
1292 pub fn load_outputs_to_watch<F: Deref>(&self, filter: &F) where F::Target: chain::Filter {
1293 let lock = self.inner.lock().unwrap();
1294 filter.register_tx(&lock.get_funding_txo().0.txid, &lock.get_funding_txo().1);
1295 for (txid, outputs) in lock.get_outputs_to_watch().iter() {
1296 for (index, script_pubkey) in outputs.iter() {
1297 assert!(*index <= u16::max_value() as u32);
1298 filter.register_output(WatchedOutput {
1300 outpoint: OutPoint { txid: *txid, index: *index as u16 },
1301 script_pubkey: script_pubkey.clone(),
1307 /// Get the list of HTLCs who's status has been updated on chain. This should be called by
1308 /// ChannelManager via [`chain::Watch::release_pending_monitor_events`].
1309 pub fn get_and_clear_pending_monitor_events(&self) -> Vec<MonitorEvent> {
1310 self.inner.lock().unwrap().get_and_clear_pending_monitor_events()
1313 /// Gets the list of pending events which were generated by previous actions, clearing the list
1316 /// This is called by the [`EventsProvider::process_pending_events`] implementation for
1317 /// [`ChainMonitor`].
1319 /// [`EventsProvider::process_pending_events`]: crate::events::EventsProvider::process_pending_events
1320 /// [`ChainMonitor`]: crate::chain::chainmonitor::ChainMonitor
1321 pub fn get_and_clear_pending_events(&self) -> Vec<Event> {
1322 self.inner.lock().unwrap().get_and_clear_pending_events()
1325 pub(crate) fn get_min_seen_secret(&self) -> u64 {
1326 self.inner.lock().unwrap().get_min_seen_secret()
1329 pub(crate) fn get_cur_counterparty_commitment_number(&self) -> u64 {
1330 self.inner.lock().unwrap().get_cur_counterparty_commitment_number()
1333 pub(crate) fn get_cur_holder_commitment_number(&self) -> u64 {
1334 self.inner.lock().unwrap().get_cur_holder_commitment_number()
1337 /// Gets the `node_id` of the counterparty for this channel.
1339 /// Will be `None` for channels constructed on LDK versions prior to 0.0.110 and always `Some`
1341 pub fn get_counterparty_node_id(&self) -> Option<PublicKey> {
1342 self.inner.lock().unwrap().counterparty_node_id
1345 /// Used by ChannelManager deserialization to broadcast the latest holder state if its copy of
1346 /// the Channel was out-of-date.
1348 /// You may also use this to broadcast the latest local commitment transaction, either because
1349 /// a monitor update failed with [`ChannelMonitorUpdateStatus::PermanentFailure`] or because we've
1350 /// fallen behind (i.e. we've received proof that our counterparty side knows a revocation
1351 /// secret we gave them that they shouldn't know).
1353 /// Broadcasting these transactions in the second case is UNSAFE, as they allow counterparty
1354 /// side to punish you. Nevertheless you may want to broadcast them if counterparty doesn't
1355 /// close channel with their commitment transaction after a substantial amount of time. Best
1356 /// may be to contact the other node operator out-of-band to coordinate other options available
1357 /// to you. In any-case, the choice is up to you.
1359 /// [`ChannelMonitorUpdateStatus::PermanentFailure`]: super::ChannelMonitorUpdateStatus::PermanentFailure
1360 pub fn get_latest_holder_commitment_txn<L: Deref>(&self, logger: &L) -> Vec<Transaction>
1361 where L::Target: Logger {
1362 self.inner.lock().unwrap().get_latest_holder_commitment_txn(logger)
1365 /// Unsafe test-only version of get_latest_holder_commitment_txn used by our test framework
1366 /// to bypass HolderCommitmentTransaction state update lockdown after signature and generate
1367 /// revoked commitment transaction.
1368 #[cfg(any(test, feature = "unsafe_revoked_tx_signing"))]
1369 pub fn unsafe_get_latest_holder_commitment_txn<L: Deref>(&self, logger: &L) -> Vec<Transaction>
1370 where L::Target: Logger {
1371 self.inner.lock().unwrap().unsafe_get_latest_holder_commitment_txn(logger)
1374 /// Processes transactions in a newly connected block, which may result in any of the following:
1375 /// - update the monitor's state against resolved HTLCs
1376 /// - punish the counterparty in the case of seeing a revoked commitment transaction
1377 /// - force close the channel and claim/timeout incoming/outgoing HTLCs if near expiration
1378 /// - detect settled outputs for later spending
1379 /// - schedule and bump any in-flight claims
1381 /// Returns any new outputs to watch from `txdata`; after called, these are also included in
1382 /// [`get_outputs_to_watch`].
1384 /// [`get_outputs_to_watch`]: #method.get_outputs_to_watch
1385 pub fn block_connected<B: Deref, F: Deref, L: Deref>(
1387 header: &BlockHeader,
1388 txdata: &TransactionData,
1393 ) -> Vec<TransactionOutputs>
1395 B::Target: BroadcasterInterface,
1396 F::Target: FeeEstimator,
1399 self.inner.lock().unwrap().block_connected(
1400 header, txdata, height, broadcaster, fee_estimator, logger)
1403 /// Determines if the disconnected block contained any transactions of interest and updates
1405 pub fn block_disconnected<B: Deref, F: Deref, L: Deref>(
1407 header: &BlockHeader,
1413 B::Target: BroadcasterInterface,
1414 F::Target: FeeEstimator,
1417 self.inner.lock().unwrap().block_disconnected(
1418 header, height, broadcaster, fee_estimator, logger)
1421 /// Processes transactions confirmed in a block with the given header and height, returning new
1422 /// outputs to watch. See [`block_connected`] for details.
1424 /// Used instead of [`block_connected`] by clients that are notified of transactions rather than
1425 /// blocks. See [`chain::Confirm`] for calling expectations.
1427 /// [`block_connected`]: Self::block_connected
1428 pub fn transactions_confirmed<B: Deref, F: Deref, L: Deref>(
1430 header: &BlockHeader,
1431 txdata: &TransactionData,
1436 ) -> Vec<TransactionOutputs>
1438 B::Target: BroadcasterInterface,
1439 F::Target: FeeEstimator,
1442 let bounded_fee_estimator = LowerBoundedFeeEstimator::new(fee_estimator);
1443 self.inner.lock().unwrap().transactions_confirmed(
1444 header, txdata, height, broadcaster, &bounded_fee_estimator, logger)
1447 /// Processes a transaction that was reorganized out of the chain.
1449 /// Used instead of [`block_disconnected`] by clients that are notified of transactions rather
1450 /// than blocks. See [`chain::Confirm`] for calling expectations.
1452 /// [`block_disconnected`]: Self::block_disconnected
1453 pub fn transaction_unconfirmed<B: Deref, F: Deref, L: Deref>(
1460 B::Target: BroadcasterInterface,
1461 F::Target: FeeEstimator,
1464 let bounded_fee_estimator = LowerBoundedFeeEstimator::new(fee_estimator);
1465 self.inner.lock().unwrap().transaction_unconfirmed(
1466 txid, broadcaster, &bounded_fee_estimator, logger);
1469 /// Updates the monitor with the current best chain tip, returning new outputs to watch. See
1470 /// [`block_connected`] for details.
1472 /// Used instead of [`block_connected`] by clients that are notified of transactions rather than
1473 /// blocks. See [`chain::Confirm`] for calling expectations.
1475 /// [`block_connected`]: Self::block_connected
1476 pub fn best_block_updated<B: Deref, F: Deref, L: Deref>(
1478 header: &BlockHeader,
1483 ) -> Vec<TransactionOutputs>
1485 B::Target: BroadcasterInterface,
1486 F::Target: FeeEstimator,
1489 let bounded_fee_estimator = LowerBoundedFeeEstimator::new(fee_estimator);
1490 self.inner.lock().unwrap().best_block_updated(
1491 header, height, broadcaster, &bounded_fee_estimator, logger)
1494 /// Returns the set of txids that should be monitored for re-organization out of the chain.
1495 pub fn get_relevant_txids(&self) -> Vec<(Txid, Option<BlockHash>)> {
1496 let inner = self.inner.lock().unwrap();
1497 let mut txids: Vec<(Txid, Option<BlockHash>)> = inner.onchain_events_awaiting_threshold_conf
1499 .map(|entry| (entry.txid, entry.block_hash))
1500 .chain(inner.onchain_tx_handler.get_relevant_txids().into_iter())
1502 txids.sort_unstable();
1507 /// Gets the latest best block which was connected either via the [`chain::Listen`] or
1508 /// [`chain::Confirm`] interfaces.
1509 pub fn current_best_block(&self) -> BestBlock {
1510 self.inner.lock().unwrap().best_block.clone()
1513 /// Triggers rebroadcasts/fee-bumps of pending claims from a force-closed channel. This is
1514 /// crucial in preventing certain classes of pinning attacks, detecting substantial mempool
1515 /// feerate changes between blocks, and ensuring reliability if broadcasting fails. We recommend
1516 /// invoking this every 30 seconds, or lower if running in an environment with spotty
1517 /// connections, like on mobile.
1518 pub fn rebroadcast_pending_claims<B: Deref, F: Deref, L: Deref>(
1519 &self, broadcaster: B, fee_estimator: F, logger: L,
1522 B::Target: BroadcasterInterface,
1523 F::Target: FeeEstimator,
1526 let fee_estimator = LowerBoundedFeeEstimator::new(fee_estimator);
1527 let mut inner = self.inner.lock().unwrap();
1528 let current_height = inner.best_block.height;
1529 inner.onchain_tx_handler.rebroadcast_pending_claims(
1530 current_height, &broadcaster, &fee_estimator, &logger,
1535 impl<Signer: WriteableEcdsaChannelSigner> ChannelMonitorImpl<Signer> {
1536 /// Helper for get_claimable_balances which does the work for an individual HTLC, generating up
1537 /// to one `Balance` for the HTLC.
1538 fn get_htlc_balance(&self, htlc: &HTLCOutputInCommitment, holder_commitment: bool,
1539 counterparty_revoked_commitment: bool, confirmed_txid: Option<Txid>)
1540 -> Option<Balance> {
1541 let htlc_commitment_tx_output_idx =
1542 if let Some(v) = htlc.transaction_output_index { v } else { return None; };
1544 let mut htlc_spend_txid_opt = None;
1545 let mut htlc_spend_tx_opt = None;
1546 let mut holder_timeout_spend_pending = None;
1547 let mut htlc_spend_pending = None;
1548 let mut holder_delayed_output_pending = None;
1549 for event in self.onchain_events_awaiting_threshold_conf.iter() {
1551 OnchainEvent::HTLCUpdate { commitment_tx_output_idx, htlc_value_satoshis, .. }
1552 if commitment_tx_output_idx == Some(htlc_commitment_tx_output_idx) => {
1553 debug_assert!(htlc_spend_txid_opt.is_none());
1554 htlc_spend_txid_opt = Some(&event.txid);
1555 debug_assert!(htlc_spend_tx_opt.is_none());
1556 htlc_spend_tx_opt = event.transaction.as_ref();
1557 debug_assert!(holder_timeout_spend_pending.is_none());
1558 debug_assert_eq!(htlc_value_satoshis.unwrap(), htlc.amount_msat / 1000);
1559 holder_timeout_spend_pending = Some(event.confirmation_threshold());
1561 OnchainEvent::HTLCSpendConfirmation { commitment_tx_output_idx, preimage, .. }
1562 if commitment_tx_output_idx == htlc_commitment_tx_output_idx => {
1563 debug_assert!(htlc_spend_txid_opt.is_none());
1564 htlc_spend_txid_opt = Some(&event.txid);
1565 debug_assert!(htlc_spend_tx_opt.is_none());
1566 htlc_spend_tx_opt = event.transaction.as_ref();
1567 debug_assert!(htlc_spend_pending.is_none());
1568 htlc_spend_pending = Some((event.confirmation_threshold(), preimage.is_some()));
1570 OnchainEvent::MaturingOutput {
1571 descriptor: SpendableOutputDescriptor::DelayedPaymentOutput(ref descriptor) }
1572 if descriptor.outpoint.index as u32 == htlc_commitment_tx_output_idx => {
1573 debug_assert!(holder_delayed_output_pending.is_none());
1574 holder_delayed_output_pending = Some(event.confirmation_threshold());
1579 let htlc_resolved = self.htlcs_resolved_on_chain.iter()
1580 .find(|v| if v.commitment_tx_output_idx == Some(htlc_commitment_tx_output_idx) {
1581 debug_assert!(htlc_spend_txid_opt.is_none());
1582 htlc_spend_txid_opt = v.resolving_txid.as_ref();
1583 debug_assert!(htlc_spend_tx_opt.is_none());
1584 htlc_spend_tx_opt = v.resolving_tx.as_ref();
1587 debug_assert!(holder_timeout_spend_pending.is_some() as u8 + htlc_spend_pending.is_some() as u8 + htlc_resolved.is_some() as u8 <= 1);
1589 let htlc_commitment_outpoint = BitcoinOutPoint::new(confirmed_txid.unwrap(), htlc_commitment_tx_output_idx);
1590 let htlc_output_to_spend =
1591 if let Some(txid) = htlc_spend_txid_opt {
1592 // Because HTLC transactions either only have 1 input and 1 output (pre-anchors) or
1593 // are signed with SIGHASH_SINGLE|ANYONECANPAY under BIP-0143 (post-anchors), we can
1594 // locate the correct output by ensuring its adjacent input spends the HTLC output
1595 // in the commitment.
1596 if let Some(ref tx) = htlc_spend_tx_opt {
1597 let htlc_input_idx_opt = tx.input.iter().enumerate()
1598 .find(|(_, input)| input.previous_output == htlc_commitment_outpoint)
1599 .map(|(idx, _)| idx as u32);
1600 debug_assert!(htlc_input_idx_opt.is_some());
1601 BitcoinOutPoint::new(*txid, htlc_input_idx_opt.unwrap_or(0))
1603 debug_assert!(!self.onchain_tx_handler.opt_anchors());
1604 BitcoinOutPoint::new(*txid, 0)
1607 htlc_commitment_outpoint
1609 let htlc_output_spend_pending = self.onchain_tx_handler.is_output_spend_pending(&htlc_output_to_spend);
1611 if let Some(conf_thresh) = holder_delayed_output_pending {
1612 debug_assert!(holder_commitment);
1613 return Some(Balance::ClaimableAwaitingConfirmations {
1614 claimable_amount_satoshis: htlc.amount_msat / 1000,
1615 confirmation_height: conf_thresh,
1617 } else if htlc_resolved.is_some() && !htlc_output_spend_pending {
1618 // Funding transaction spends should be fully confirmed by the time any
1619 // HTLC transactions are resolved, unless we're talking about a holder
1620 // commitment tx, whose resolution is delayed until the CSV timeout is
1621 // reached, even though HTLCs may be resolved after only
1622 // ANTI_REORG_DELAY confirmations.
1623 debug_assert!(holder_commitment || self.funding_spend_confirmed.is_some());
1624 } else if counterparty_revoked_commitment {
1625 let htlc_output_claim_pending = self.onchain_events_awaiting_threshold_conf.iter().find_map(|event| {
1626 if let OnchainEvent::MaturingOutput {
1627 descriptor: SpendableOutputDescriptor::StaticOutput { .. }
1629 if event.transaction.as_ref().map(|tx| tx.input.iter().any(|inp| {
1630 if let Some(htlc_spend_txid) = htlc_spend_txid_opt {
1631 tx.txid() == *htlc_spend_txid || inp.previous_output.txid == *htlc_spend_txid
1633 Some(inp.previous_output.txid) == confirmed_txid &&
1634 inp.previous_output.vout == htlc_commitment_tx_output_idx
1636 })).unwrap_or(false) {
1641 if htlc_output_claim_pending.is_some() {
1642 // We already push `Balance`s onto the `res` list for every
1643 // `StaticOutput` in a `MaturingOutput` in the revoked
1644 // counterparty commitment transaction case generally, so don't
1645 // need to do so again here.
1647 debug_assert!(holder_timeout_spend_pending.is_none(),
1648 "HTLCUpdate OnchainEvents should never appear for preimage claims");
1649 debug_assert!(!htlc.offered || htlc_spend_pending.is_none() || !htlc_spend_pending.unwrap().1,
1650 "We don't (currently) generate preimage claims against revoked outputs, where did you get one?!");
1651 return Some(Balance::CounterpartyRevokedOutputClaimable {
1652 claimable_amount_satoshis: htlc.amount_msat / 1000,
1655 } else if htlc.offered == holder_commitment {
1656 // If the payment was outbound, check if there's an HTLCUpdate
1657 // indicating we have spent this HTLC with a timeout, claiming it back
1658 // and awaiting confirmations on it.
1659 if let Some(conf_thresh) = holder_timeout_spend_pending {
1660 return Some(Balance::ClaimableAwaitingConfirmations {
1661 claimable_amount_satoshis: htlc.amount_msat / 1000,
1662 confirmation_height: conf_thresh,
1665 return Some(Balance::MaybeTimeoutClaimableHTLC {
1666 claimable_amount_satoshis: htlc.amount_msat / 1000,
1667 claimable_height: htlc.cltv_expiry,
1668 payment_hash: htlc.payment_hash,
1671 } else if let Some(payment_preimage) = self.payment_preimages.get(&htlc.payment_hash) {
1672 // Otherwise (the payment was inbound), only expose it as claimable if
1673 // we know the preimage.
1674 // Note that if there is a pending claim, but it did not use the
1675 // preimage, we lost funds to our counterparty! We will then continue
1676 // to show it as ContentiousClaimable until ANTI_REORG_DELAY.
1677 debug_assert!(holder_timeout_spend_pending.is_none());
1678 if let Some((conf_thresh, true)) = htlc_spend_pending {
1679 return Some(Balance::ClaimableAwaitingConfirmations {
1680 claimable_amount_satoshis: htlc.amount_msat / 1000,
1681 confirmation_height: conf_thresh,
1684 return Some(Balance::ContentiousClaimable {
1685 claimable_amount_satoshis: htlc.amount_msat / 1000,
1686 timeout_height: htlc.cltv_expiry,
1687 payment_hash: htlc.payment_hash,
1688 payment_preimage: *payment_preimage,
1691 } else if htlc_resolved.is_none() {
1692 return Some(Balance::MaybePreimageClaimableHTLC {
1693 claimable_amount_satoshis: htlc.amount_msat / 1000,
1694 expiry_height: htlc.cltv_expiry,
1695 payment_hash: htlc.payment_hash,
1702 impl<Signer: WriteableEcdsaChannelSigner> ChannelMonitor<Signer> {
1703 /// Gets the balances in this channel which are either claimable by us if we were to
1704 /// force-close the channel now or which are claimable on-chain (possibly awaiting
1707 /// Any balances in the channel which are available on-chain (excluding on-chain fees) are
1708 /// included here until an [`Event::SpendableOutputs`] event has been generated for the
1709 /// balance, or until our counterparty has claimed the balance and accrued several
1710 /// confirmations on the claim transaction.
1712 /// Note that for `ChannelMonitors` which track a channel which went on-chain with versions of
1713 /// LDK prior to 0.0.111, balances may not be fully captured if our counterparty broadcasted
1714 /// a revoked state.
1716 /// See [`Balance`] for additional details on the types of claimable balances which
1717 /// may be returned here and their meanings.
1718 pub fn get_claimable_balances(&self) -> Vec<Balance> {
1719 let mut res = Vec::new();
1720 let us = self.inner.lock().unwrap();
1722 let mut confirmed_txid = us.funding_spend_confirmed;
1723 let mut confirmed_counterparty_output = us.confirmed_commitment_tx_counterparty_output;
1724 let mut pending_commitment_tx_conf_thresh = None;
1725 let funding_spend_pending = us.onchain_events_awaiting_threshold_conf.iter().find_map(|event| {
1726 if let OnchainEvent::FundingSpendConfirmation { commitment_tx_to_counterparty_output, .. } =
1729 confirmed_counterparty_output = commitment_tx_to_counterparty_output;
1730 Some((event.txid, event.confirmation_threshold()))
1733 if let Some((txid, conf_thresh)) = funding_spend_pending {
1734 debug_assert!(us.funding_spend_confirmed.is_none(),
1735 "We have a pending funding spend awaiting anti-reorg confirmation, we can't have confirmed it already!");
1736 confirmed_txid = Some(txid);
1737 pending_commitment_tx_conf_thresh = Some(conf_thresh);
1740 macro_rules! walk_htlcs {
1741 ($holder_commitment: expr, $counterparty_revoked_commitment: expr, $htlc_iter: expr) => {
1742 for htlc in $htlc_iter {
1743 if htlc.transaction_output_index.is_some() {
1745 if let Some(bal) = us.get_htlc_balance(htlc, $holder_commitment, $counterparty_revoked_commitment, confirmed_txid) {
1753 if let Some(txid) = confirmed_txid {
1754 let mut found_commitment_tx = false;
1755 if let Some(counterparty_tx_htlcs) = us.counterparty_claimable_outpoints.get(&txid) {
1756 // First look for the to_remote output back to us.
1757 if let Some(conf_thresh) = pending_commitment_tx_conf_thresh {
1758 if let Some(value) = us.onchain_events_awaiting_threshold_conf.iter().find_map(|event| {
1759 if let OnchainEvent::MaturingOutput {
1760 descriptor: SpendableOutputDescriptor::StaticPaymentOutput(descriptor)
1762 Some(descriptor.output.value)
1765 res.push(Balance::ClaimableAwaitingConfirmations {
1766 claimable_amount_satoshis: value,
1767 confirmation_height: conf_thresh,
1770 // If a counterparty commitment transaction is awaiting confirmation, we
1771 // should either have a StaticPaymentOutput MaturingOutput event awaiting
1772 // confirmation with the same height or have never met our dust amount.
1775 if Some(txid) == us.current_counterparty_commitment_txid || Some(txid) == us.prev_counterparty_commitment_txid {
1776 walk_htlcs!(false, false, counterparty_tx_htlcs.iter().map(|(a, _)| a));
1778 walk_htlcs!(false, true, counterparty_tx_htlcs.iter().map(|(a, _)| a));
1779 // The counterparty broadcasted a revoked state!
1780 // Look for any StaticOutputs first, generating claimable balances for those.
1781 // If any match the confirmed counterparty revoked to_self output, skip
1782 // generating a CounterpartyRevokedOutputClaimable.
1783 let mut spent_counterparty_output = false;
1784 for event in us.onchain_events_awaiting_threshold_conf.iter() {
1785 if let OnchainEvent::MaturingOutput {
1786 descriptor: SpendableOutputDescriptor::StaticOutput { output, .. }
1788 res.push(Balance::ClaimableAwaitingConfirmations {
1789 claimable_amount_satoshis: output.value,
1790 confirmation_height: event.confirmation_threshold(),
1792 if let Some(confirmed_to_self_idx) = confirmed_counterparty_output.map(|(idx, _)| idx) {
1793 if event.transaction.as_ref().map(|tx|
1794 tx.input.iter().any(|inp| inp.previous_output.vout == confirmed_to_self_idx)
1795 ).unwrap_or(false) {
1796 spent_counterparty_output = true;
1802 if spent_counterparty_output {
1803 } else if let Some((confirmed_to_self_idx, amt)) = confirmed_counterparty_output {
1804 let output_spendable = us.onchain_tx_handler
1805 .is_output_spend_pending(&BitcoinOutPoint::new(txid, confirmed_to_self_idx));
1806 if output_spendable {
1807 res.push(Balance::CounterpartyRevokedOutputClaimable {
1808 claimable_amount_satoshis: amt,
1812 // Counterparty output is missing, either it was broadcasted on a
1813 // previous version of LDK or the counterparty hadn't met dust.
1816 found_commitment_tx = true;
1817 } else if txid == us.current_holder_commitment_tx.txid {
1818 walk_htlcs!(true, false, us.current_holder_commitment_tx.htlc_outputs.iter().map(|(a, _, _)| a));
1819 if let Some(conf_thresh) = pending_commitment_tx_conf_thresh {
1820 res.push(Balance::ClaimableAwaitingConfirmations {
1821 claimable_amount_satoshis: us.current_holder_commitment_tx.to_self_value_sat,
1822 confirmation_height: conf_thresh,
1825 found_commitment_tx = true;
1826 } else if let Some(prev_commitment) = &us.prev_holder_signed_commitment_tx {
1827 if txid == prev_commitment.txid {
1828 walk_htlcs!(true, false, prev_commitment.htlc_outputs.iter().map(|(a, _, _)| a));
1829 if let Some(conf_thresh) = pending_commitment_tx_conf_thresh {
1830 res.push(Balance::ClaimableAwaitingConfirmations {
1831 claimable_amount_satoshis: prev_commitment.to_self_value_sat,
1832 confirmation_height: conf_thresh,
1835 found_commitment_tx = true;
1838 if !found_commitment_tx {
1839 if let Some(conf_thresh) = pending_commitment_tx_conf_thresh {
1840 // We blindly assume this is a cooperative close transaction here, and that
1841 // neither us nor our counterparty misbehaved. At worst we've under-estimated
1842 // the amount we can claim as we'll punish a misbehaving counterparty.
1843 res.push(Balance::ClaimableAwaitingConfirmations {
1844 claimable_amount_satoshis: us.current_holder_commitment_tx.to_self_value_sat,
1845 confirmation_height: conf_thresh,
1850 let mut claimable_inbound_htlc_value_sat = 0;
1851 for (htlc, _, _) in us.current_holder_commitment_tx.htlc_outputs.iter() {
1852 if htlc.transaction_output_index.is_none() { continue; }
1854 res.push(Balance::MaybeTimeoutClaimableHTLC {
1855 claimable_amount_satoshis: htlc.amount_msat / 1000,
1856 claimable_height: htlc.cltv_expiry,
1857 payment_hash: htlc.payment_hash,
1859 } else if us.payment_preimages.get(&htlc.payment_hash).is_some() {
1860 claimable_inbound_htlc_value_sat += htlc.amount_msat / 1000;
1862 // As long as the HTLC is still in our latest commitment state, treat
1863 // it as potentially claimable, even if it has long-since expired.
1864 res.push(Balance::MaybePreimageClaimableHTLC {
1865 claimable_amount_satoshis: htlc.amount_msat / 1000,
1866 expiry_height: htlc.cltv_expiry,
1867 payment_hash: htlc.payment_hash,
1871 res.push(Balance::ClaimableOnChannelClose {
1872 claimable_amount_satoshis: us.current_holder_commitment_tx.to_self_value_sat + claimable_inbound_htlc_value_sat,
1879 /// Gets the set of outbound HTLCs which can be (or have been) resolved by this
1880 /// `ChannelMonitor`. This is used to determine if an HTLC was removed from the channel prior
1881 /// to the `ChannelManager` having been persisted.
1883 /// This is similar to [`Self::get_pending_or_resolved_outbound_htlcs`] except it includes
1884 /// HTLCs which were resolved on-chain (i.e. where the final HTLC resolution was done by an
1885 /// event from this `ChannelMonitor`).
1886 pub(crate) fn get_all_current_outbound_htlcs(&self) -> HashMap<HTLCSource, (HTLCOutputInCommitment, Option<PaymentPreimage>)> {
1887 let mut res = HashMap::new();
1888 // Just examine the available counterparty commitment transactions. See docs on
1889 // `fail_unbroadcast_htlcs`, below, for justification.
1890 let us = self.inner.lock().unwrap();
1891 macro_rules! walk_counterparty_commitment {
1893 if let Some(ref latest_outpoints) = us.counterparty_claimable_outpoints.get($txid) {
1894 for &(ref htlc, ref source_option) in latest_outpoints.iter() {
1895 if let &Some(ref source) = source_option {
1896 res.insert((**source).clone(), (htlc.clone(),
1897 us.counterparty_fulfilled_htlcs.get(&SentHTLCId::from_source(source)).cloned()));
1903 if let Some(ref txid) = us.current_counterparty_commitment_txid {
1904 walk_counterparty_commitment!(txid);
1906 if let Some(ref txid) = us.prev_counterparty_commitment_txid {
1907 walk_counterparty_commitment!(txid);
1912 /// Gets the set of outbound HTLCs which are pending resolution in this channel or which were
1913 /// resolved with a preimage from our counterparty.
1915 /// This is used to reconstruct pending outbound payments on restart in the ChannelManager.
1917 /// Currently, the preimage is unused, however if it is present in the relevant internal state
1918 /// an HTLC is always included even if it has been resolved.
1919 pub(crate) fn get_pending_or_resolved_outbound_htlcs(&self) -> HashMap<HTLCSource, (HTLCOutputInCommitment, Option<PaymentPreimage>)> {
1920 let us = self.inner.lock().unwrap();
1921 // We're only concerned with the confirmation count of HTLC transactions, and don't
1922 // actually care how many confirmations a commitment transaction may or may not have. Thus,
1923 // we look for either a FundingSpendConfirmation event or a funding_spend_confirmed.
1924 let confirmed_txid = us.funding_spend_confirmed.or_else(|| {
1925 us.onchain_events_awaiting_threshold_conf.iter().find_map(|event| {
1926 if let OnchainEvent::FundingSpendConfirmation { .. } = event.event {
1932 if confirmed_txid.is_none() {
1933 // If we have not seen a commitment transaction on-chain (ie the channel is not yet
1934 // closed), just get the full set.
1936 return self.get_all_current_outbound_htlcs();
1939 let mut res = HashMap::new();
1940 macro_rules! walk_htlcs {
1941 ($holder_commitment: expr, $htlc_iter: expr) => {
1942 for (htlc, source) in $htlc_iter {
1943 if us.htlcs_resolved_on_chain.iter().any(|v| v.commitment_tx_output_idx == htlc.transaction_output_index) {
1944 // We should assert that funding_spend_confirmed is_some() here, but we
1945 // have some unit tests which violate HTLC transaction CSVs entirely and
1947 // TODO: Once tests all connect transactions at consensus-valid times, we
1948 // should assert here like we do in `get_claimable_balances`.
1949 } else if htlc.offered == $holder_commitment {
1950 // If the payment was outbound, check if there's an HTLCUpdate
1951 // indicating we have spent this HTLC with a timeout, claiming it back
1952 // and awaiting confirmations on it.
1953 let htlc_update_confd = us.onchain_events_awaiting_threshold_conf.iter().any(|event| {
1954 if let OnchainEvent::HTLCUpdate { commitment_tx_output_idx: Some(commitment_tx_output_idx), .. } = event.event {
1955 // If the HTLC was timed out, we wait for ANTI_REORG_DELAY blocks
1956 // before considering it "no longer pending" - this matches when we
1957 // provide the ChannelManager an HTLC failure event.
1958 Some(commitment_tx_output_idx) == htlc.transaction_output_index &&
1959 us.best_block.height() >= event.height + ANTI_REORG_DELAY - 1
1960 } else if let OnchainEvent::HTLCSpendConfirmation { commitment_tx_output_idx, .. } = event.event {
1961 // If the HTLC was fulfilled with a preimage, we consider the HTLC
1962 // immediately non-pending, matching when we provide ChannelManager
1964 Some(commitment_tx_output_idx) == htlc.transaction_output_index
1967 let counterparty_resolved_preimage_opt =
1968 us.counterparty_fulfilled_htlcs.get(&SentHTLCId::from_source(source)).cloned();
1969 if !htlc_update_confd || counterparty_resolved_preimage_opt.is_some() {
1970 res.insert(source.clone(), (htlc.clone(), counterparty_resolved_preimage_opt));
1977 let txid = confirmed_txid.unwrap();
1978 if Some(txid) == us.current_counterparty_commitment_txid || Some(txid) == us.prev_counterparty_commitment_txid {
1979 walk_htlcs!(false, us.counterparty_claimable_outpoints.get(&txid).unwrap().iter().filter_map(|(a, b)| {
1980 if let &Some(ref source) = b {
1981 Some((a, &**source))
1984 } else if txid == us.current_holder_commitment_tx.txid {
1985 walk_htlcs!(true, us.current_holder_commitment_tx.htlc_outputs.iter().filter_map(|(a, _, c)| {
1986 if let Some(source) = c { Some((a, source)) } else { None }
1988 } else if let Some(prev_commitment) = &us.prev_holder_signed_commitment_tx {
1989 if txid == prev_commitment.txid {
1990 walk_htlcs!(true, prev_commitment.htlc_outputs.iter().filter_map(|(a, _, c)| {
1991 if let Some(source) = c { Some((a, source)) } else { None }
1999 pub(crate) fn get_stored_preimages(&self) -> HashMap<PaymentHash, PaymentPreimage> {
2000 self.inner.lock().unwrap().payment_preimages.clone()
2004 /// Compares a broadcasted commitment transaction's HTLCs with those in the latest state,
2005 /// failing any HTLCs which didn't make it into the broadcasted commitment transaction back
2006 /// after ANTI_REORG_DELAY blocks.
2008 /// We always compare against the set of HTLCs in counterparty commitment transactions, as those
2009 /// are the commitment transactions which are generated by us. The off-chain state machine in
2010 /// `Channel` will automatically resolve any HTLCs which were never included in a commitment
2011 /// transaction when it detects channel closure, but it is up to us to ensure any HTLCs which were
2012 /// included in a remote commitment transaction are failed back if they are not present in the
2013 /// broadcasted commitment transaction.
2015 /// Specifically, the removal process for HTLCs in `Channel` is always based on the counterparty
2016 /// sending a `revoke_and_ack`, which causes us to clear `prev_counterparty_commitment_txid`. Thus,
2017 /// as long as we examine both the current counterparty commitment transaction and, if it hasn't
2018 /// been revoked yet, the previous one, we we will never "forget" to resolve an HTLC.
2019 macro_rules! fail_unbroadcast_htlcs {
2020 ($self: expr, $commitment_tx_type: expr, $commitment_txid_confirmed: expr, $commitment_tx_confirmed: expr,
2021 $commitment_tx_conf_height: expr, $commitment_tx_conf_hash: expr, $confirmed_htlcs_list: expr, $logger: expr) => { {
2022 debug_assert_eq!($commitment_tx_confirmed.txid(), $commitment_txid_confirmed);
2024 macro_rules! check_htlc_fails {
2025 ($txid: expr, $commitment_tx: expr) => {
2026 if let Some(ref latest_outpoints) = $self.counterparty_claimable_outpoints.get($txid) {
2027 for &(ref htlc, ref source_option) in latest_outpoints.iter() {
2028 if let &Some(ref source) = source_option {
2029 // Check if the HTLC is present in the commitment transaction that was
2030 // broadcast, but not if it was below the dust limit, which we should
2031 // fail backwards immediately as there is no way for us to learn the
2032 // payment_preimage.
2033 // Note that if the dust limit were allowed to change between
2034 // commitment transactions we'd want to be check whether *any*
2035 // broadcastable commitment transaction has the HTLC in it, but it
2036 // cannot currently change after channel initialization, so we don't
2038 let confirmed_htlcs_iter: &mut Iterator<Item = (&HTLCOutputInCommitment, Option<&HTLCSource>)> = &mut $confirmed_htlcs_list;
2040 let mut matched_htlc = false;
2041 for (ref broadcast_htlc, ref broadcast_source) in confirmed_htlcs_iter {
2042 if broadcast_htlc.transaction_output_index.is_some() &&
2043 (Some(&**source) == *broadcast_source ||
2044 (broadcast_source.is_none() &&
2045 broadcast_htlc.payment_hash == htlc.payment_hash &&
2046 broadcast_htlc.amount_msat == htlc.amount_msat)) {
2047 matched_htlc = true;
2051 if matched_htlc { continue; }
2052 if $self.counterparty_fulfilled_htlcs.get(&SentHTLCId::from_source(source)).is_some() {
2055 $self.onchain_events_awaiting_threshold_conf.retain(|ref entry| {
2056 if entry.height != $commitment_tx_conf_height { return true; }
2058 OnchainEvent::HTLCUpdate { source: ref update_source, .. } => {
2059 *update_source != **source
2064 let entry = OnchainEventEntry {
2065 txid: $commitment_txid_confirmed,
2066 transaction: Some($commitment_tx_confirmed.clone()),
2067 height: $commitment_tx_conf_height,
2068 block_hash: Some(*$commitment_tx_conf_hash),
2069 event: OnchainEvent::HTLCUpdate {
2070 source: (**source).clone(),
2071 payment_hash: htlc.payment_hash.clone(),
2072 htlc_value_satoshis: Some(htlc.amount_msat / 1000),
2073 commitment_tx_output_idx: None,
2076 log_trace!($logger, "Failing HTLC with payment_hash {} from {} counterparty commitment tx due to broadcast of {} commitment transaction {}, waiting for confirmation (at height {})",
2077 log_bytes!(htlc.payment_hash.0), $commitment_tx, $commitment_tx_type,
2078 $commitment_txid_confirmed, entry.confirmation_threshold());
2079 $self.onchain_events_awaiting_threshold_conf.push(entry);
2085 if let Some(ref txid) = $self.current_counterparty_commitment_txid {
2086 check_htlc_fails!(txid, "current");
2088 if let Some(ref txid) = $self.prev_counterparty_commitment_txid {
2089 check_htlc_fails!(txid, "previous");
2094 // In the `test_invalid_funding_tx` test, we need a bogus script which matches the HTLC-Accepted
2095 // witness length match (ie is 136 bytes long). We generate one here which we also use in some
2096 // in-line tests later.
2099 pub fn deliberately_bogus_accepted_htlc_witness_program() -> Vec<u8> {
2100 let mut ret = [opcodes::all::OP_NOP.to_u8(); 136];
2101 ret[131] = opcodes::all::OP_DROP.to_u8();
2102 ret[132] = opcodes::all::OP_DROP.to_u8();
2103 ret[133] = opcodes::all::OP_DROP.to_u8();
2104 ret[134] = opcodes::all::OP_DROP.to_u8();
2105 ret[135] = opcodes::OP_TRUE.to_u8();
2110 pub fn deliberately_bogus_accepted_htlc_witness() -> Vec<Vec<u8>> {
2111 vec![Vec::new(), Vec::new(), Vec::new(), Vec::new(), deliberately_bogus_accepted_htlc_witness_program().into()].into()
2114 impl<Signer: WriteableEcdsaChannelSigner> ChannelMonitorImpl<Signer> {
2115 /// Inserts a revocation secret into this channel monitor. Prunes old preimages if neither
2116 /// needed by holder commitment transactions HTCLs nor by counterparty ones. Unless we haven't already seen
2117 /// counterparty commitment transaction's secret, they are de facto pruned (we can use revocation key).
2118 fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), &'static str> {
2119 if let Err(()) = self.commitment_secrets.provide_secret(idx, secret) {
2120 return Err("Previous secret did not match new one");
2123 // Prune HTLCs from the previous counterparty commitment tx so we don't generate failure/fulfill
2124 // events for now-revoked/fulfilled HTLCs.
2125 if let Some(txid) = self.prev_counterparty_commitment_txid.take() {
2126 if self.current_counterparty_commitment_txid.unwrap() != txid {
2127 let cur_claimables = self.counterparty_claimable_outpoints.get(
2128 &self.current_counterparty_commitment_txid.unwrap()).unwrap();
2129 for (_, ref source_opt) in self.counterparty_claimable_outpoints.get(&txid).unwrap() {
2130 if let Some(source) = source_opt {
2131 if !cur_claimables.iter()
2132 .any(|(_, cur_source_opt)| cur_source_opt == source_opt)
2134 self.counterparty_fulfilled_htlcs.remove(&SentHTLCId::from_source(source));
2138 for &mut (_, ref mut source_opt) in self.counterparty_claimable_outpoints.get_mut(&txid).unwrap() {
2142 assert!(cfg!(fuzzing), "Commitment txids are unique outside of fuzzing, where hashes can collide");
2146 if !self.payment_preimages.is_empty() {
2147 let cur_holder_signed_commitment_tx = &self.current_holder_commitment_tx;
2148 let prev_holder_signed_commitment_tx = self.prev_holder_signed_commitment_tx.as_ref();
2149 let min_idx = self.get_min_seen_secret();
2150 let counterparty_hash_commitment_number = &mut self.counterparty_hash_commitment_number;
2152 self.payment_preimages.retain(|&k, _| {
2153 for &(ref htlc, _, _) in cur_holder_signed_commitment_tx.htlc_outputs.iter() {
2154 if k == htlc.payment_hash {
2158 if let Some(prev_holder_commitment_tx) = prev_holder_signed_commitment_tx {
2159 for &(ref htlc, _, _) in prev_holder_commitment_tx.htlc_outputs.iter() {
2160 if k == htlc.payment_hash {
2165 let contains = if let Some(cn) = counterparty_hash_commitment_number.get(&k) {
2172 counterparty_hash_commitment_number.remove(&k);
2181 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_per_commitment_point: PublicKey, logger: &L) where L::Target: Logger {
2182 // TODO: Encrypt the htlc_outputs data with the single-hash of the commitment transaction
2183 // so that a remote monitor doesn't learn anything unless there is a malicious close.
2184 // (only maybe, sadly we cant do the same for local info, as we need to be aware of
2186 for &(ref htlc, _) in &htlc_outputs {
2187 self.counterparty_hash_commitment_number.insert(htlc.payment_hash, commitment_number);
2190 log_trace!(logger, "Tracking new counterparty commitment transaction with txid {} at commitment number {} with {} HTLC outputs", txid, commitment_number, htlc_outputs.len());
2191 self.prev_counterparty_commitment_txid = self.current_counterparty_commitment_txid.take();
2192 self.current_counterparty_commitment_txid = Some(txid);
2193 self.counterparty_claimable_outpoints.insert(txid, htlc_outputs.clone());
2194 self.current_counterparty_commitment_number = commitment_number;
2195 //TODO: Merge this into the other per-counterparty-transaction output storage stuff
2196 match self.their_cur_per_commitment_points {
2197 Some(old_points) => {
2198 if old_points.0 == commitment_number + 1 {
2199 self.their_cur_per_commitment_points = Some((old_points.0, old_points.1, Some(their_per_commitment_point)));
2200 } else if old_points.0 == commitment_number + 2 {
2201 if let Some(old_second_point) = old_points.2 {
2202 self.their_cur_per_commitment_points = Some((old_points.0 - 1, old_second_point, Some(their_per_commitment_point)));
2204 self.their_cur_per_commitment_points = Some((commitment_number, their_per_commitment_point, None));
2207 self.their_cur_per_commitment_points = Some((commitment_number, their_per_commitment_point, None));
2211 self.their_cur_per_commitment_points = Some((commitment_number, their_per_commitment_point, None));
2214 let mut htlcs = Vec::with_capacity(htlc_outputs.len());
2215 for htlc in htlc_outputs {
2216 if htlc.0.transaction_output_index.is_some() {
2222 /// Informs this monitor of the latest holder (ie broadcastable) commitment transaction. The
2223 /// monitor watches for timeouts and may broadcast it if we approach such a timeout. Thus, it
2224 /// is important that any clones of this channel monitor (including remote clones) by kept
2225 /// up-to-date as our holder commitment transaction is updated.
2226 /// Panics if set_on_holder_tx_csv has never been called.
2227 fn provide_latest_holder_commitment_tx(&mut self, holder_commitment_tx: HolderCommitmentTransaction, mut htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>, claimed_htlcs: &[(SentHTLCId, PaymentPreimage)], nondust_htlc_sources: Vec<HTLCSource>) -> Result<(), &'static str> {
2228 if htlc_outputs.iter().any(|(_, s, _)| s.is_some()) {
2229 // If we have non-dust HTLCs in htlc_outputs, ensure they match the HTLCs in the
2230 // `holder_commitment_tx`. In the future, we'll no longer provide the redundant data
2231 // and just pass in source data via `nondust_htlc_sources`.
2232 debug_assert_eq!(htlc_outputs.iter().filter(|(_, s, _)| s.is_some()).count(), holder_commitment_tx.trust().htlcs().len());
2233 for (a, b) in htlc_outputs.iter().filter(|(_, s, _)| s.is_some()).map(|(h, _, _)| h).zip(holder_commitment_tx.trust().htlcs().iter()) {
2234 debug_assert_eq!(a, b);
2236 debug_assert_eq!(htlc_outputs.iter().filter(|(_, s, _)| s.is_some()).count(), holder_commitment_tx.counterparty_htlc_sigs.len());
2237 for (a, b) in htlc_outputs.iter().filter_map(|(_, s, _)| s.as_ref()).zip(holder_commitment_tx.counterparty_htlc_sigs.iter()) {
2238 debug_assert_eq!(a, b);
2240 debug_assert!(nondust_htlc_sources.is_empty());
2242 // If we don't have any non-dust HTLCs in htlc_outputs, assume they were all passed via
2243 // `nondust_htlc_sources`, building up the final htlc_outputs by combining
2244 // `nondust_htlc_sources` and the `holder_commitment_tx`
2245 #[cfg(debug_assertions)] {
2247 for htlc in holder_commitment_tx.trust().htlcs().iter() {
2248 assert!(htlc.transaction_output_index.unwrap() as i32 > prev);
2249 prev = htlc.transaction_output_index.unwrap() as i32;
2252 debug_assert!(htlc_outputs.iter().all(|(htlc, _, _)| htlc.transaction_output_index.is_none()));
2253 debug_assert!(htlc_outputs.iter().all(|(_, sig_opt, _)| sig_opt.is_none()));
2254 debug_assert_eq!(holder_commitment_tx.trust().htlcs().len(), holder_commitment_tx.counterparty_htlc_sigs.len());
2256 let mut sources_iter = nondust_htlc_sources.into_iter();
2258 for (htlc, counterparty_sig) in holder_commitment_tx.trust().htlcs().iter()
2259 .zip(holder_commitment_tx.counterparty_htlc_sigs.iter())
2262 let source = sources_iter.next().expect("Non-dust HTLC sources didn't match commitment tx");
2263 #[cfg(debug_assertions)] {
2264 assert!(source.possibly_matches_output(htlc));
2266 htlc_outputs.push((htlc.clone(), Some(counterparty_sig.clone()), Some(source)));
2268 htlc_outputs.push((htlc.clone(), Some(counterparty_sig.clone()), None));
2271 debug_assert!(sources_iter.next().is_none());
2274 let trusted_tx = holder_commitment_tx.trust();
2275 let txid = trusted_tx.txid();
2276 let tx_keys = trusted_tx.keys();
2277 self.current_holder_commitment_number = trusted_tx.commitment_number();
2278 let mut new_holder_commitment_tx = HolderSignedTx {
2280 revocation_key: tx_keys.revocation_key,
2281 a_htlc_key: tx_keys.broadcaster_htlc_key,
2282 b_htlc_key: tx_keys.countersignatory_htlc_key,
2283 delayed_payment_key: tx_keys.broadcaster_delayed_payment_key,
2284 per_commitment_point: tx_keys.per_commitment_point,
2286 to_self_value_sat: holder_commitment_tx.to_broadcaster_value_sat(),
2287 feerate_per_kw: trusted_tx.feerate_per_kw(),
2289 self.onchain_tx_handler.provide_latest_holder_tx(holder_commitment_tx);
2290 mem::swap(&mut new_holder_commitment_tx, &mut self.current_holder_commitment_tx);
2291 self.prev_holder_signed_commitment_tx = Some(new_holder_commitment_tx);
2292 for (claimed_htlc_id, claimed_preimage) in claimed_htlcs {
2293 #[cfg(debug_assertions)] {
2294 let cur_counterparty_htlcs = self.counterparty_claimable_outpoints.get(
2295 &self.current_counterparty_commitment_txid.unwrap()).unwrap();
2296 assert!(cur_counterparty_htlcs.iter().any(|(_, source_opt)| {
2297 if let Some(source) = source_opt {
2298 SentHTLCId::from_source(source) == *claimed_htlc_id
2302 self.counterparty_fulfilled_htlcs.insert(*claimed_htlc_id, *claimed_preimage);
2304 if self.holder_tx_signed {
2305 return Err("Latest holder commitment signed has already been signed, update is rejected");
2310 /// Provides a payment_hash->payment_preimage mapping. Will be automatically pruned when all
2311 /// commitment_tx_infos which contain the payment hash have been revoked.
2312 fn provide_payment_preimage<B: Deref, F: Deref, L: Deref>(
2313 &mut self, payment_hash: &PaymentHash, payment_preimage: &PaymentPreimage, broadcaster: &B,
2314 fee_estimator: &LowerBoundedFeeEstimator<F>, logger: &L)
2315 where B::Target: BroadcasterInterface,
2316 F::Target: FeeEstimator,
2319 self.payment_preimages.insert(payment_hash.clone(), payment_preimage.clone());
2321 // If the channel is force closed, try to claim the output from this preimage.
2322 // First check if a counterparty commitment transaction has been broadcasted:
2323 macro_rules! claim_htlcs {
2324 ($commitment_number: expr, $txid: expr) => {
2325 let (htlc_claim_reqs, _) = self.get_counterparty_output_claim_info($commitment_number, $txid, None);
2326 self.onchain_tx_handler.update_claims_view_from_requests(htlc_claim_reqs, self.best_block.height(), self.best_block.height(), broadcaster, fee_estimator, logger);
2329 if let Some(txid) = self.current_counterparty_commitment_txid {
2330 if let Some(commitment_number) = self.counterparty_commitment_txn_on_chain.get(&txid) {
2331 claim_htlcs!(*commitment_number, txid);
2335 if let Some(txid) = self.prev_counterparty_commitment_txid {
2336 if let Some(commitment_number) = self.counterparty_commitment_txn_on_chain.get(&txid) {
2337 claim_htlcs!(*commitment_number, txid);
2342 // Then if a holder commitment transaction has been seen on-chain, broadcast transactions
2343 // claiming the HTLC output from each of the holder commitment transactions.
2344 // Note that we can't just use `self.holder_tx_signed`, because that only covers the case where
2345 // *we* sign a holder commitment transaction, not when e.g. a watchtower broadcasts one of our
2346 // holder commitment transactions.
2347 if self.broadcasted_holder_revokable_script.is_some() {
2348 // Assume that the broadcasted commitment transaction confirmed in the current best
2349 // block. Even if not, its a reasonable metric for the bump criteria on the HTLC
2351 let (claim_reqs, _) = self.get_broadcasted_holder_claims(&self.current_holder_commitment_tx, self.best_block.height());
2352 self.onchain_tx_handler.update_claims_view_from_requests(claim_reqs, self.best_block.height(), self.best_block.height(), broadcaster, fee_estimator, logger);
2353 if let Some(ref tx) = self.prev_holder_signed_commitment_tx {
2354 let (claim_reqs, _) = self.get_broadcasted_holder_claims(&tx, self.best_block.height());
2355 self.onchain_tx_handler.update_claims_view_from_requests(claim_reqs, self.best_block.height(), self.best_block.height(), broadcaster, fee_estimator, logger);
2360 pub(crate) fn broadcast_latest_holder_commitment_txn<B: Deref, L: Deref>(&mut self, broadcaster: &B, logger: &L)
2361 where B::Target: BroadcasterInterface,
2364 let commit_txs = self.get_latest_holder_commitment_txn(logger);
2365 let mut txs = vec![];
2366 for tx in commit_txs.iter() {
2367 log_info!(logger, "Broadcasting local {}", log_tx!(tx));
2370 broadcaster.broadcast_transactions(&txs);
2371 self.pending_monitor_events.push(MonitorEvent::CommitmentTxConfirmed(self.funding_info.0));
2374 pub fn update_monitor<B: Deref, F: Deref, L: Deref>(&mut self, updates: &ChannelMonitorUpdate, broadcaster: &B, fee_estimator: F, logger: &L) -> Result<(), ()>
2375 where B::Target: BroadcasterInterface,
2376 F::Target: FeeEstimator,
2379 if self.latest_update_id == CLOSED_CHANNEL_UPDATE_ID && updates.update_id == CLOSED_CHANNEL_UPDATE_ID {
2380 log_info!(logger, "Applying post-force-closed update to monitor {} with {} change(s).",
2381 log_funding_info!(self), updates.updates.len());
2382 } else if updates.update_id == CLOSED_CHANNEL_UPDATE_ID {
2383 log_info!(logger, "Applying force close update to monitor {} with {} change(s).",
2384 log_funding_info!(self), updates.updates.len());
2386 log_info!(logger, "Applying update to monitor {}, bringing update_id from {} to {} with {} change(s).",
2387 log_funding_info!(self), self.latest_update_id, updates.update_id, updates.updates.len());
2389 // ChannelMonitor updates may be applied after force close if we receive a preimage for a
2390 // broadcasted commitment transaction HTLC output that we'd like to claim on-chain. If this
2391 // is the case, we no longer have guaranteed access to the monitor's update ID, so we use a
2392 // sentinel value instead.
2394 // The `ChannelManager` may also queue redundant `ChannelForceClosed` updates if it still
2395 // thinks the channel needs to have its commitment transaction broadcast, so we'll allow
2397 if updates.update_id == CLOSED_CHANNEL_UPDATE_ID {
2398 assert_eq!(updates.updates.len(), 1);
2399 match updates.updates[0] {
2400 ChannelMonitorUpdateStep::ChannelForceClosed { .. } => {},
2401 // We should have already seen a `ChannelForceClosed` update if we're trying to
2402 // provide a preimage at this point.
2403 ChannelMonitorUpdateStep::PaymentPreimage { .. } =>
2404 debug_assert_eq!(self.latest_update_id, CLOSED_CHANNEL_UPDATE_ID),
2406 log_error!(logger, "Attempted to apply post-force-close ChannelMonitorUpdate of type {}", updates.updates[0].variant_name());
2407 panic!("Attempted to apply post-force-close ChannelMonitorUpdate that wasn't providing a payment preimage");
2410 } else if self.latest_update_id + 1 != updates.update_id {
2411 panic!("Attempted to apply ChannelMonitorUpdates out of order, check the update_id before passing an update to update_monitor!");
2413 let mut ret = Ok(());
2414 let bounded_fee_estimator = LowerBoundedFeeEstimator::new(&*fee_estimator);
2415 for update in updates.updates.iter() {
2417 ChannelMonitorUpdateStep::LatestHolderCommitmentTXInfo { commitment_tx, htlc_outputs, claimed_htlcs, nondust_htlc_sources } => {
2418 log_trace!(logger, "Updating ChannelMonitor with latest holder commitment transaction info");
2419 if self.lockdown_from_offchain { panic!(); }
2420 if let Err(e) = self.provide_latest_holder_commitment_tx(commitment_tx.clone(), htlc_outputs.clone(), &claimed_htlcs, nondust_htlc_sources.clone()) {
2421 log_error!(logger, "Providing latest holder commitment transaction failed/was refused:");
2422 log_error!(logger, " {}", e);
2426 ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo { commitment_txid, htlc_outputs, commitment_number, their_per_commitment_point } => {
2427 log_trace!(logger, "Updating ChannelMonitor with latest counterparty commitment transaction info");
2428 self.provide_latest_counterparty_commitment_tx(*commitment_txid, htlc_outputs.clone(), *commitment_number, *their_per_commitment_point, logger)
2430 ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage } => {
2431 log_trace!(logger, "Updating ChannelMonitor with payment preimage");
2432 self.provide_payment_preimage(&PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()), &payment_preimage, broadcaster, &bounded_fee_estimator, logger)
2434 ChannelMonitorUpdateStep::CommitmentSecret { idx, secret } => {
2435 log_trace!(logger, "Updating ChannelMonitor with commitment secret");
2436 if let Err(e) = self.provide_secret(*idx, *secret) {
2437 log_error!(logger, "Providing latest counterparty commitment secret failed/was refused:");
2438 log_error!(logger, " {}", e);
2442 ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast } => {
2443 log_trace!(logger, "Updating ChannelMonitor: channel force closed, should broadcast: {}", should_broadcast);
2444 self.lockdown_from_offchain = true;
2445 if *should_broadcast {
2446 // There's no need to broadcast our commitment transaction if we've seen one
2447 // confirmed (even with 1 confirmation) as it'll be rejected as
2448 // duplicate/conflicting.
2449 let detected_funding_spend = self.funding_spend_confirmed.is_some() ||
2450 self.onchain_events_awaiting_threshold_conf.iter().find(|event| match event.event {
2451 OnchainEvent::FundingSpendConfirmation { .. } => true,
2454 if detected_funding_spend {
2455 log_trace!(logger, "Avoiding commitment broadcast, already detected confirmed spend onchain");
2458 self.broadcast_latest_holder_commitment_txn(broadcaster, logger);
2459 // If the channel supports anchor outputs, we'll need to emit an external
2460 // event to be consumed such that a child transaction is broadcast with a
2461 // high enough feerate for the parent commitment transaction to confirm.
2462 if self.onchain_tx_handler.opt_anchors() {
2463 let funding_output = HolderFundingOutput::build(
2464 self.funding_redeemscript.clone(), self.channel_value_satoshis,
2465 self.onchain_tx_handler.opt_anchors(),
2467 let best_block_height = self.best_block.height();
2468 let commitment_package = PackageTemplate::build_package(
2469 self.funding_info.0.txid.clone(), self.funding_info.0.index as u32,
2470 PackageSolvingData::HolderFundingOutput(funding_output),
2471 best_block_height, best_block_height
2473 self.onchain_tx_handler.update_claims_view_from_requests(
2474 vec![commitment_package], best_block_height, best_block_height,
2475 broadcaster, &bounded_fee_estimator, logger,
2478 } else if !self.holder_tx_signed {
2479 log_error!(logger, "WARNING: You have a potentially-unsafe holder commitment transaction available to broadcast");
2480 log_error!(logger, " in channel monitor for channel {}!", log_bytes!(self.funding_info.0.to_channel_id()));
2481 log_error!(logger, " Read the docs for ChannelMonitor::get_latest_holder_commitment_txn and take manual action!");
2483 // If we generated a MonitorEvent::CommitmentTxConfirmed, the ChannelManager
2484 // will still give us a ChannelForceClosed event with !should_broadcast, but we
2485 // shouldn't print the scary warning above.
2486 log_info!(logger, "Channel off-chain state closed after we broadcasted our latest commitment transaction.");
2489 ChannelMonitorUpdateStep::ShutdownScript { scriptpubkey } => {
2490 log_trace!(logger, "Updating ChannelMonitor with shutdown script");
2491 if let Some(shutdown_script) = self.shutdown_script.replace(scriptpubkey.clone()) {
2492 panic!("Attempted to replace shutdown script {} with {}", shutdown_script, scriptpubkey);
2498 // If the updates succeeded and we were in an already closed channel state, then there's no
2499 // need to refuse any updates we expect to receive afer seeing a confirmed commitment.
2500 if ret.is_ok() && updates.update_id == CLOSED_CHANNEL_UPDATE_ID && self.latest_update_id == updates.update_id {
2504 self.latest_update_id = updates.update_id;
2506 // Refuse updates after we've detected a spend onchain, but only if we haven't processed a
2507 // force closed monitor update yet.
2508 if ret.is_ok() && self.funding_spend_seen && self.latest_update_id != CLOSED_CHANNEL_UPDATE_ID {
2509 log_error!(logger, "Refusing Channel Monitor Update as counterparty attempted to update commitment after funding was spent");
2514 pub fn get_latest_update_id(&self) -> u64 {
2515 self.latest_update_id
2518 pub fn get_funding_txo(&self) -> &(OutPoint, Script) {
2522 pub fn get_outputs_to_watch(&self) -> &HashMap<Txid, Vec<(u32, Script)>> {
2523 // If we've detected a counterparty commitment tx on chain, we must include it in the set
2524 // of outputs to watch for spends of, otherwise we're likely to lose user funds. Because
2525 // its trivial to do, double-check that here.
2526 for (txid, _) in self.counterparty_commitment_txn_on_chain.iter() {
2527 self.outputs_to_watch.get(txid).expect("Counterparty commitment txn which have been broadcast should have outputs registered");
2529 &self.outputs_to_watch
2532 pub fn get_and_clear_pending_monitor_events(&mut self) -> Vec<MonitorEvent> {
2533 let mut ret = Vec::new();
2534 mem::swap(&mut ret, &mut self.pending_monitor_events);
2538 pub fn get_and_clear_pending_events(&mut self) -> Vec<Event> {
2539 let mut ret = Vec::new();
2540 mem::swap(&mut ret, &mut self.pending_events);
2542 for (claim_id, claim_event) in self.onchain_tx_handler.get_and_clear_pending_claim_events().drain(..) {
2544 ClaimEvent::BumpCommitment {
2545 package_target_feerate_sat_per_1000_weight, commitment_tx, anchor_output_idx,
2547 let commitment_txid = commitment_tx.txid();
2548 debug_assert_eq!(self.current_holder_commitment_tx.txid, commitment_txid);
2549 let pending_htlcs = self.current_holder_commitment_tx.non_dust_htlcs();
2550 let commitment_tx_fee_satoshis = self.channel_value_satoshis -
2551 commitment_tx.output.iter().fold(0u64, |sum, output| sum + output.value);
2552 ret.push(Event::BumpTransaction(BumpTransactionEvent::ChannelClose {
2554 package_target_feerate_sat_per_1000_weight,
2556 commitment_tx_fee_satoshis,
2557 anchor_descriptor: AnchorDescriptor {
2558 channel_keys_id: self.channel_keys_id,
2559 channel_value_satoshis: self.channel_value_satoshis,
2560 outpoint: BitcoinOutPoint {
2561 txid: commitment_txid,
2562 vout: anchor_output_idx,
2568 ClaimEvent::BumpHTLC {
2569 target_feerate_sat_per_1000_weight, htlcs, tx_lock_time,
2571 let mut htlc_descriptors = Vec::with_capacity(htlcs.len());
2573 htlc_descriptors.push(HTLCDescriptor {
2574 channel_keys_id: self.channel_keys_id,
2575 channel_value_satoshis: self.channel_value_satoshis,
2576 channel_parameters: self.onchain_tx_handler.channel_transaction_parameters.clone(),
2577 commitment_txid: htlc.commitment_txid,
2578 per_commitment_number: htlc.per_commitment_number,
2580 preimage: htlc.preimage,
2581 counterparty_sig: htlc.counterparty_sig,
2584 ret.push(Event::BumpTransaction(BumpTransactionEvent::HTLCResolution {
2586 target_feerate_sat_per_1000_weight,
2596 /// Can only fail if idx is < get_min_seen_secret
2597 fn get_secret(&self, idx: u64) -> Option<[u8; 32]> {
2598 self.commitment_secrets.get_secret(idx)
2601 pub(crate) fn get_min_seen_secret(&self) -> u64 {
2602 self.commitment_secrets.get_min_seen_secret()
2605 pub(crate) fn get_cur_counterparty_commitment_number(&self) -> u64 {
2606 self.current_counterparty_commitment_number
2609 pub(crate) fn get_cur_holder_commitment_number(&self) -> u64 {
2610 self.current_holder_commitment_number
2613 /// Attempts to claim a counterparty commitment transaction's outputs using the revocation key and
2614 /// data in counterparty_claimable_outpoints. Will directly claim any HTLC outputs which expire at a
2615 /// height > height + CLTV_SHARED_CLAIM_BUFFER. In any case, will install monitoring for
2616 /// HTLC-Success/HTLC-Timeout transactions.
2618 /// Returns packages to claim the revoked output(s), as well as additional outputs to watch and
2619 /// general information about the output that is to the counterparty in the commitment
2621 fn check_spend_counterparty_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, block_hash: &BlockHash, logger: &L)
2622 -> (Vec<PackageTemplate>, TransactionOutputs, CommitmentTxCounterpartyOutputInfo)
2623 where L::Target: Logger {
2624 // Most secp and related errors trying to create keys means we have no hope of constructing
2625 // a spend transaction...so we return no transactions to broadcast
2626 let mut claimable_outpoints = Vec::new();
2627 let mut watch_outputs = Vec::new();
2628 let mut to_counterparty_output_info = None;
2630 let commitment_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
2631 let per_commitment_option = self.counterparty_claimable_outpoints.get(&commitment_txid);
2633 macro_rules! ignore_error {
2634 ( $thing : expr ) => {
2637 Err(_) => return (claimable_outpoints, (commitment_txid, watch_outputs), to_counterparty_output_info)
2642 let commitment_number = 0xffffffffffff - ((((tx.input[0].sequence.0 as u64 & 0xffffff) << 3*8) | (tx.lock_time.0 as u64 & 0xffffff)) ^ self.commitment_transaction_number_obscure_factor);
2643 if commitment_number >= self.get_min_seen_secret() {
2644 let secret = self.get_secret(commitment_number).unwrap();
2645 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
2646 let per_commitment_point = PublicKey::from_secret_key(&self.onchain_tx_handler.secp_ctx, &per_commitment_key);
2647 let revocation_pubkey = chan_utils::derive_public_revocation_key(&self.onchain_tx_handler.secp_ctx, &per_commitment_point, &self.holder_revocation_basepoint);
2648 let delayed_key = chan_utils::derive_public_key(&self.onchain_tx_handler.secp_ctx, &PublicKey::from_secret_key(&self.onchain_tx_handler.secp_ctx, &per_commitment_key), &self.counterparty_commitment_params.counterparty_delayed_payment_base_key);
2650 let revokeable_redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.counterparty_commitment_params.on_counterparty_tx_csv, &delayed_key);
2651 let revokeable_p2wsh = revokeable_redeemscript.to_v0_p2wsh();
2653 // First, process non-htlc outputs (to_holder & to_counterparty)
2654 for (idx, outp) in tx.output.iter().enumerate() {
2655 if outp.script_pubkey == revokeable_p2wsh {
2656 let revk_outp = RevokedOutput::build(per_commitment_point, self.counterparty_commitment_params.counterparty_delayed_payment_base_key, self.counterparty_commitment_params.counterparty_htlc_base_key, per_commitment_key, outp.value, self.counterparty_commitment_params.on_counterparty_tx_csv, self.onchain_tx_handler.opt_anchors());
2657 let justice_package = PackageTemplate::build_package(commitment_txid, idx as u32, PackageSolvingData::RevokedOutput(revk_outp), height + self.counterparty_commitment_params.on_counterparty_tx_csv as u32, height);
2658 claimable_outpoints.push(justice_package);
2659 to_counterparty_output_info =
2660 Some((idx.try_into().expect("Txn can't have more than 2^32 outputs"), outp.value));
2664 // Then, try to find revoked htlc outputs
2665 if let Some(ref per_commitment_data) = per_commitment_option {
2666 for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
2667 if let Some(transaction_output_index) = htlc.transaction_output_index {
2668 if transaction_output_index as usize >= tx.output.len() ||
2669 tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
2670 // per_commitment_data is corrupt or our commitment signing key leaked!
2671 return (claimable_outpoints, (commitment_txid, watch_outputs),
2672 to_counterparty_output_info);
2674 let revk_htlc_outp = RevokedHTLCOutput::build(per_commitment_point, self.counterparty_commitment_params.counterparty_delayed_payment_base_key, self.counterparty_commitment_params.counterparty_htlc_base_key, per_commitment_key, htlc.amount_msat / 1000, htlc.clone(), self.onchain_tx_handler.channel_transaction_parameters.opt_anchors.is_some());
2675 let justice_package = PackageTemplate::build_package(commitment_txid, transaction_output_index, PackageSolvingData::RevokedHTLCOutput(revk_htlc_outp), htlc.cltv_expiry, height);
2676 claimable_outpoints.push(justice_package);
2681 // Last, track onchain revoked commitment transaction and fail backward outgoing HTLCs as payment path is broken
2682 if !claimable_outpoints.is_empty() || per_commitment_option.is_some() { // ie we're confident this is actually ours
2683 // We're definitely a counterparty commitment transaction!
2684 log_error!(logger, "Got broadcast of revoked counterparty commitment transaction, going to generate general spend tx with {} inputs", claimable_outpoints.len());
2685 for (idx, outp) in tx.output.iter().enumerate() {
2686 watch_outputs.push((idx as u32, outp.clone()));
2688 self.counterparty_commitment_txn_on_chain.insert(commitment_txid, commitment_number);
2690 if let Some(per_commitment_data) = per_commitment_option {
2691 fail_unbroadcast_htlcs!(self, "revoked_counterparty", commitment_txid, tx, height,
2692 block_hash, per_commitment_data.iter().map(|(htlc, htlc_source)|
2693 (htlc, htlc_source.as_ref().map(|htlc_source| htlc_source.as_ref()))
2696 debug_assert!(false, "We should have per-commitment option for any recognized old commitment txn");
2697 fail_unbroadcast_htlcs!(self, "revoked counterparty", commitment_txid, tx, height,
2698 block_hash, [].iter().map(|reference| *reference), logger);
2701 } else if let Some(per_commitment_data) = per_commitment_option {
2702 // While this isn't useful yet, there is a potential race where if a counterparty
2703 // revokes a state at the same time as the commitment transaction for that state is
2704 // confirmed, and the watchtower receives the block before the user, the user could
2705 // upload a new ChannelMonitor with the revocation secret but the watchtower has
2706 // already processed the block, resulting in the counterparty_commitment_txn_on_chain entry
2707 // not being generated by the above conditional. Thus, to be safe, we go ahead and
2709 for (idx, outp) in tx.output.iter().enumerate() {
2710 watch_outputs.push((idx as u32, outp.clone()));
2712 self.counterparty_commitment_txn_on_chain.insert(commitment_txid, commitment_number);
2714 log_info!(logger, "Got broadcast of non-revoked counterparty commitment transaction {}", commitment_txid);
2715 fail_unbroadcast_htlcs!(self, "counterparty", commitment_txid, tx, height, block_hash,
2716 per_commitment_data.iter().map(|(htlc, htlc_source)|
2717 (htlc, htlc_source.as_ref().map(|htlc_source| htlc_source.as_ref()))
2720 let (htlc_claim_reqs, counterparty_output_info) =
2721 self.get_counterparty_output_claim_info(commitment_number, commitment_txid, Some(tx));
2722 to_counterparty_output_info = counterparty_output_info;
2723 for req in htlc_claim_reqs {
2724 claimable_outpoints.push(req);
2728 (claimable_outpoints, (commitment_txid, watch_outputs), to_counterparty_output_info)
2731 /// Returns the HTLC claim package templates and the counterparty output info
2732 fn get_counterparty_output_claim_info(&self, commitment_number: u64, commitment_txid: Txid, tx: Option<&Transaction>)
2733 -> (Vec<PackageTemplate>, CommitmentTxCounterpartyOutputInfo) {
2734 let mut claimable_outpoints = Vec::new();
2735 let mut to_counterparty_output_info: CommitmentTxCounterpartyOutputInfo = None;
2737 let htlc_outputs = match self.counterparty_claimable_outpoints.get(&commitment_txid) {
2738 Some(outputs) => outputs,
2739 None => return (claimable_outpoints, to_counterparty_output_info),
2741 let per_commitment_points = match self.their_cur_per_commitment_points {
2742 Some(points) => points,
2743 None => return (claimable_outpoints, to_counterparty_output_info),
2746 let per_commitment_point =
2747 // If the counterparty commitment tx is the latest valid state, use their latest
2748 // per-commitment point
2749 if per_commitment_points.0 == commitment_number { &per_commitment_points.1 }
2750 else if let Some(point) = per_commitment_points.2.as_ref() {
2751 // If counterparty commitment tx is the state previous to the latest valid state, use
2752 // their previous per-commitment point (non-atomicity of revocation means it's valid for
2753 // them to temporarily have two valid commitment txns from our viewpoint)
2754 if per_commitment_points.0 == commitment_number + 1 {
2756 } else { return (claimable_outpoints, to_counterparty_output_info); }
2757 } else { return (claimable_outpoints, to_counterparty_output_info); };
2759 if let Some(transaction) = tx {
2760 let revocation_pubkey = chan_utils::derive_public_revocation_key(
2761 &self.onchain_tx_handler.secp_ctx, &per_commitment_point, &self.holder_revocation_basepoint);
2762 let delayed_key = chan_utils::derive_public_key(&self.onchain_tx_handler.secp_ctx,
2763 &per_commitment_point,
2764 &self.counterparty_commitment_params.counterparty_delayed_payment_base_key);
2765 let revokeable_p2wsh = chan_utils::get_revokeable_redeemscript(&revocation_pubkey,
2766 self.counterparty_commitment_params.on_counterparty_tx_csv,
2767 &delayed_key).to_v0_p2wsh();
2768 for (idx, outp) in transaction.output.iter().enumerate() {
2769 if outp.script_pubkey == revokeable_p2wsh {
2770 to_counterparty_output_info =
2771 Some((idx.try_into().expect("Can't have > 2^32 outputs"), outp.value));
2776 for (_, &(ref htlc, _)) in htlc_outputs.iter().enumerate() {
2777 if let Some(transaction_output_index) = htlc.transaction_output_index {
2778 if let Some(transaction) = tx {
2779 if transaction_output_index as usize >= transaction.output.len() ||
2780 transaction.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
2781 // per_commitment_data is corrupt or our commitment signing key leaked!
2782 return (claimable_outpoints, to_counterparty_output_info);
2785 let preimage = if htlc.offered { if let Some(p) = self.payment_preimages.get(&htlc.payment_hash) { Some(*p) } else { None } } else { None };
2786 if preimage.is_some() || !htlc.offered {
2787 let counterparty_htlc_outp = if htlc.offered {
2788 PackageSolvingData::CounterpartyOfferedHTLCOutput(
2789 CounterpartyOfferedHTLCOutput::build(*per_commitment_point,
2790 self.counterparty_commitment_params.counterparty_delayed_payment_base_key,
2791 self.counterparty_commitment_params.counterparty_htlc_base_key,
2792 preimage.unwrap(), htlc.clone(), self.onchain_tx_handler.opt_anchors()))
2794 PackageSolvingData::CounterpartyReceivedHTLCOutput(
2795 CounterpartyReceivedHTLCOutput::build(*per_commitment_point,
2796 self.counterparty_commitment_params.counterparty_delayed_payment_base_key,
2797 self.counterparty_commitment_params.counterparty_htlc_base_key,
2798 htlc.clone(), self.onchain_tx_handler.opt_anchors()))
2800 let counterparty_package = PackageTemplate::build_package(commitment_txid, transaction_output_index, counterparty_htlc_outp, htlc.cltv_expiry, 0);
2801 claimable_outpoints.push(counterparty_package);
2806 (claimable_outpoints, to_counterparty_output_info)
2809 /// Attempts to claim a counterparty HTLC-Success/HTLC-Timeout's outputs using the revocation key
2810 fn check_spend_counterparty_htlc<L: Deref>(
2811 &mut self, tx: &Transaction, commitment_number: u64, commitment_txid: &Txid, height: u32, logger: &L
2812 ) -> (Vec<PackageTemplate>, Option<TransactionOutputs>) where L::Target: Logger {
2813 let secret = if let Some(secret) = self.get_secret(commitment_number) { secret } else { return (Vec::new(), None); };
2814 let per_commitment_key = match SecretKey::from_slice(&secret) {
2816 Err(_) => return (Vec::new(), None)
2818 let per_commitment_point = PublicKey::from_secret_key(&self.onchain_tx_handler.secp_ctx, &per_commitment_key);
2820 let htlc_txid = tx.txid();
2821 let mut claimable_outpoints = vec![];
2822 let mut outputs_to_watch = None;
2823 // Previously, we would only claim HTLCs from revoked HTLC transactions if they had 1 input
2824 // with a witness of 5 elements and 1 output. This wasn't enough for anchor outputs, as the
2825 // counterparty can now aggregate multiple HTLCs into a single transaction thanks to
2826 // `SIGHASH_SINGLE` remote signatures, leading us to not claim any HTLCs upon seeing a
2827 // confirmed revoked HTLC transaction (for more details, see
2828 // https://lists.linuxfoundation.org/pipermail/lightning-dev/2022-April/003561.html).
2830 // We make sure we're not vulnerable to this case by checking all inputs of the transaction,
2831 // and claim those which spend the commitment transaction, have a witness of 5 elements, and
2832 // have a corresponding output at the same index within the transaction.
2833 for (idx, input) in tx.input.iter().enumerate() {
2834 if input.previous_output.txid == *commitment_txid && input.witness.len() == 5 && tx.output.get(idx).is_some() {
2835 log_error!(logger, "Got broadcast of revoked counterparty HTLC transaction, spending {}:{}", htlc_txid, idx);
2836 let revk_outp = RevokedOutput::build(
2837 per_commitment_point, self.counterparty_commitment_params.counterparty_delayed_payment_base_key,
2838 self.counterparty_commitment_params.counterparty_htlc_base_key, per_commitment_key,
2839 tx.output[idx].value, self.counterparty_commitment_params.on_counterparty_tx_csv,
2842 let justice_package = PackageTemplate::build_package(
2843 htlc_txid, idx as u32, PackageSolvingData::RevokedOutput(revk_outp),
2844 height + self.counterparty_commitment_params.on_counterparty_tx_csv as u32, height
2846 claimable_outpoints.push(justice_package);
2847 if outputs_to_watch.is_none() {
2848 outputs_to_watch = Some((htlc_txid, vec![]));
2850 outputs_to_watch.as_mut().unwrap().1.push((idx as u32, tx.output[idx].clone()));
2853 (claimable_outpoints, outputs_to_watch)
2856 // Returns (1) `PackageTemplate`s that can be given to the OnchainTxHandler, so that the handler can
2857 // broadcast transactions claiming holder HTLC commitment outputs and (2) a holder revokable
2858 // script so we can detect whether a holder transaction has been seen on-chain.
2859 fn get_broadcasted_holder_claims(&self, holder_tx: &HolderSignedTx, conf_height: u32) -> (Vec<PackageTemplate>, Option<(Script, PublicKey, PublicKey)>) {
2860 let mut claim_requests = Vec::with_capacity(holder_tx.htlc_outputs.len());
2862 let redeemscript = chan_utils::get_revokeable_redeemscript(&holder_tx.revocation_key, self.on_holder_tx_csv, &holder_tx.delayed_payment_key);
2863 let broadcasted_holder_revokable_script = Some((redeemscript.to_v0_p2wsh(), holder_tx.per_commitment_point.clone(), holder_tx.revocation_key.clone()));
2865 for &(ref htlc, _, _) in holder_tx.htlc_outputs.iter() {
2866 if let Some(transaction_output_index) = htlc.transaction_output_index {
2867 let htlc_output = if htlc.offered {
2868 let htlc_output = HolderHTLCOutput::build_offered(
2869 htlc.amount_msat, htlc.cltv_expiry, self.onchain_tx_handler.opt_anchors()
2873 let payment_preimage = if let Some(preimage) = self.payment_preimages.get(&htlc.payment_hash) {
2876 // We can't build an HTLC-Success transaction without the preimage
2879 let htlc_output = HolderHTLCOutput::build_accepted(
2880 payment_preimage, htlc.amount_msat, self.onchain_tx_handler.opt_anchors()
2884 let htlc_package = PackageTemplate::build_package(
2885 holder_tx.txid, transaction_output_index,
2886 PackageSolvingData::HolderHTLCOutput(htlc_output),
2887 htlc.cltv_expiry, conf_height
2889 claim_requests.push(htlc_package);
2893 (claim_requests, broadcasted_holder_revokable_script)
2896 // Returns holder HTLC outputs to watch and react to in case of spending.
2897 fn get_broadcasted_holder_watch_outputs(&self, holder_tx: &HolderSignedTx, commitment_tx: &Transaction) -> Vec<(u32, TxOut)> {
2898 let mut watch_outputs = Vec::with_capacity(holder_tx.htlc_outputs.len());
2899 for &(ref htlc, _, _) in holder_tx.htlc_outputs.iter() {
2900 if let Some(transaction_output_index) = htlc.transaction_output_index {
2901 watch_outputs.push((transaction_output_index, commitment_tx.output[transaction_output_index as usize].clone()));
2907 /// Attempts to claim any claimable HTLCs in a commitment transaction which was not (yet)
2908 /// revoked using data in holder_claimable_outpoints.
2909 /// Should not be used if check_spend_revoked_transaction succeeds.
2910 /// Returns None unless the transaction is definitely one of our commitment transactions.
2911 fn check_spend_holder_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, block_hash: &BlockHash, logger: &L) -> Option<(Vec<PackageTemplate>, TransactionOutputs)> where L::Target: Logger {
2912 let commitment_txid = tx.txid();
2913 let mut claim_requests = Vec::new();
2914 let mut watch_outputs = Vec::new();
2916 macro_rules! append_onchain_update {
2917 ($updates: expr, $to_watch: expr) => {
2918 claim_requests = $updates.0;
2919 self.broadcasted_holder_revokable_script = $updates.1;
2920 watch_outputs.append(&mut $to_watch);
2924 // HTLCs set may differ between last and previous holder commitment txn, in case of one them hitting chain, ensure we cancel all HTLCs backward
2925 let mut is_holder_tx = false;
2927 if self.current_holder_commitment_tx.txid == commitment_txid {
2928 is_holder_tx = true;
2929 log_info!(logger, "Got broadcast of latest holder commitment tx {}, searching for available HTLCs to claim", commitment_txid);
2930 let res = self.get_broadcasted_holder_claims(&self.current_holder_commitment_tx, height);
2931 let mut to_watch = self.get_broadcasted_holder_watch_outputs(&self.current_holder_commitment_tx, tx);
2932 append_onchain_update!(res, to_watch);
2933 fail_unbroadcast_htlcs!(self, "latest holder", commitment_txid, tx, height,
2934 block_hash, self.current_holder_commitment_tx.htlc_outputs.iter()
2935 .map(|(htlc, _, htlc_source)| (htlc, htlc_source.as_ref())), logger);
2936 } else if let &Some(ref holder_tx) = &self.prev_holder_signed_commitment_tx {
2937 if holder_tx.txid == commitment_txid {
2938 is_holder_tx = true;
2939 log_info!(logger, "Got broadcast of previous holder commitment tx {}, searching for available HTLCs to claim", commitment_txid);
2940 let res = self.get_broadcasted_holder_claims(holder_tx, height);
2941 let mut to_watch = self.get_broadcasted_holder_watch_outputs(holder_tx, tx);
2942 append_onchain_update!(res, to_watch);
2943 fail_unbroadcast_htlcs!(self, "previous holder", commitment_txid, tx, height, block_hash,
2944 holder_tx.htlc_outputs.iter().map(|(htlc, _, htlc_source)| (htlc, htlc_source.as_ref())),
2950 Some((claim_requests, (commitment_txid, watch_outputs)))
2956 pub fn get_latest_holder_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
2957 log_debug!(logger, "Getting signed latest holder commitment transaction!");
2958 self.holder_tx_signed = true;
2959 let commitment_tx = self.onchain_tx_handler.get_fully_signed_holder_tx(&self.funding_redeemscript);
2960 let txid = commitment_tx.txid();
2961 let mut holder_transactions = vec![commitment_tx];
2962 // When anchor outputs are present, the HTLC transactions are only valid once the commitment
2963 // transaction confirms.
2964 if self.onchain_tx_handler.opt_anchors() {
2965 return holder_transactions;
2967 for htlc in self.current_holder_commitment_tx.htlc_outputs.iter() {
2968 if let Some(vout) = htlc.0.transaction_output_index {
2969 let preimage = if !htlc.0.offered {
2970 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
2971 // We can't build an HTLC-Success transaction without the preimage
2974 } else if htlc.0.cltv_expiry > self.best_block.height() + 1 {
2975 // Don't broadcast HTLC-Timeout transactions immediately as they don't meet the
2976 // current locktime requirements on-chain. We will broadcast them in
2977 // `block_confirmed` when `should_broadcast_holder_commitment_txn` returns true.
2978 // Note that we add + 1 as transactions are broadcastable when they can be
2979 // confirmed in the next block.
2982 if let Some(htlc_tx) = self.onchain_tx_handler.get_fully_signed_htlc_tx(
2983 &::bitcoin::OutPoint { txid, vout }, &preimage) {
2984 holder_transactions.push(htlc_tx);
2988 // 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.
2989 // The data will be re-generated and tracked in check_spend_holder_transaction if we get a confirmation.
2993 #[cfg(any(test,feature = "unsafe_revoked_tx_signing"))]
2994 /// Note that this includes possibly-locktimed-in-the-future transactions!
2995 fn unsafe_get_latest_holder_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
2996 log_debug!(logger, "Getting signed copy of latest holder commitment transaction!");
2997 let commitment_tx = self.onchain_tx_handler.get_fully_signed_copy_holder_tx(&self.funding_redeemscript);
2998 let txid = commitment_tx.txid();
2999 let mut holder_transactions = vec![commitment_tx];
3000 // When anchor outputs are present, the HTLC transactions are only final once the commitment
3001 // transaction confirms due to the CSV 1 encumberance.
3002 if self.onchain_tx_handler.opt_anchors() {
3003 return holder_transactions;
3005 for htlc in self.current_holder_commitment_tx.htlc_outputs.iter() {
3006 if let Some(vout) = htlc.0.transaction_output_index {
3007 let preimage = if !htlc.0.offered {
3008 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
3009 // We can't build an HTLC-Success transaction without the preimage
3013 if let Some(htlc_tx) = self.onchain_tx_handler.unsafe_get_fully_signed_htlc_tx(
3014 &::bitcoin::OutPoint { txid, vout }, &preimage) {
3015 holder_transactions.push(htlc_tx);
3022 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>
3023 where B::Target: BroadcasterInterface,
3024 F::Target: FeeEstimator,
3027 let block_hash = header.block_hash();
3028 self.best_block = BestBlock::new(block_hash, height);
3030 let bounded_fee_estimator = LowerBoundedFeeEstimator::new(fee_estimator);
3031 self.transactions_confirmed(header, txdata, height, broadcaster, &bounded_fee_estimator, logger)
3034 fn best_block_updated<B: Deref, F: Deref, L: Deref>(
3036 header: &BlockHeader,
3039 fee_estimator: &LowerBoundedFeeEstimator<F>,
3041 ) -> Vec<TransactionOutputs>
3043 B::Target: BroadcasterInterface,
3044 F::Target: FeeEstimator,
3047 let block_hash = header.block_hash();
3049 if height > self.best_block.height() {
3050 self.best_block = BestBlock::new(block_hash, height);
3051 self.block_confirmed(height, block_hash, vec![], vec![], vec![], &broadcaster, &fee_estimator, &logger)
3052 } else if block_hash != self.best_block.block_hash() {
3053 self.best_block = BestBlock::new(block_hash, height);
3054 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| entry.height <= height);
3055 self.onchain_tx_handler.block_disconnected(height + 1, broadcaster, fee_estimator, logger);
3057 } else { Vec::new() }
3060 fn transactions_confirmed<B: Deref, F: Deref, L: Deref>(
3062 header: &BlockHeader,
3063 txdata: &TransactionData,
3066 fee_estimator: &LowerBoundedFeeEstimator<F>,
3068 ) -> Vec<TransactionOutputs>
3070 B::Target: BroadcasterInterface,
3071 F::Target: FeeEstimator,
3074 let txn_matched = self.filter_block(txdata);
3075 for tx in &txn_matched {
3076 let mut output_val = 0;
3077 for out in tx.output.iter() {
3078 if out.value > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
3079 output_val += out.value;
3080 if output_val > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
3084 let block_hash = header.block_hash();
3086 let mut watch_outputs = Vec::new();
3087 let mut claimable_outpoints = Vec::new();
3088 'tx_iter: for tx in &txn_matched {
3089 let txid = tx.txid();
3090 // If a transaction has already been confirmed, ensure we don't bother processing it duplicatively.
3091 if Some(txid) == self.funding_spend_confirmed {
3092 log_debug!(logger, "Skipping redundant processing of funding-spend tx {} as it was previously confirmed", txid);
3095 for ev in self.onchain_events_awaiting_threshold_conf.iter() {
3096 if ev.txid == txid {
3097 if let Some(conf_hash) = ev.block_hash {
3098 assert_eq!(header.block_hash(), conf_hash,
3099 "Transaction {} was already confirmed and is being re-confirmed in a different block.\n\
3100 This indicates a severe bug in the transaction connection logic - a reorg should have been processed first!", ev.txid);
3102 log_debug!(logger, "Skipping redundant processing of confirming tx {} as it was previously confirmed", txid);
3106 for htlc in self.htlcs_resolved_on_chain.iter() {
3107 if Some(txid) == htlc.resolving_txid {
3108 log_debug!(logger, "Skipping redundant processing of HTLC resolution tx {} as it was previously confirmed", txid);
3112 for spendable_txid in self.spendable_txids_confirmed.iter() {
3113 if txid == *spendable_txid {
3114 log_debug!(logger, "Skipping redundant processing of spendable tx {} as it was previously confirmed", txid);
3119 if tx.input.len() == 1 {
3120 // Assuming our keys were not leaked (in which case we're screwed no matter what),
3121 // commitment transactions and HTLC transactions will all only ever have one input
3122 // (except for HTLC transactions for channels with anchor outputs), which is an easy
3123 // way to filter out any potential non-matching txn for lazy filters.
3124 let prevout = &tx.input[0].previous_output;
3125 if prevout.txid == self.funding_info.0.txid && prevout.vout == self.funding_info.0.index as u32 {
3126 let mut balance_spendable_csv = None;
3127 log_info!(logger, "Channel {} closed by funding output spend in txid {}.",
3128 log_bytes!(self.funding_info.0.to_channel_id()), txid);
3129 self.funding_spend_seen = true;
3130 let mut commitment_tx_to_counterparty_output = None;
3131 if (tx.input[0].sequence.0 >> 8*3) as u8 == 0x80 && (tx.lock_time.0 >> 8*3) as u8 == 0x20 {
3132 let (mut new_outpoints, new_outputs, counterparty_output_idx_sats) =
3133 self.check_spend_counterparty_transaction(&tx, height, &block_hash, &logger);
3134 commitment_tx_to_counterparty_output = counterparty_output_idx_sats;
3135 if !new_outputs.1.is_empty() {
3136 watch_outputs.push(new_outputs);
3138 claimable_outpoints.append(&mut new_outpoints);
3139 if new_outpoints.is_empty() {
3140 if let Some((mut new_outpoints, new_outputs)) = self.check_spend_holder_transaction(&tx, height, &block_hash, &logger) {
3141 debug_assert!(commitment_tx_to_counterparty_output.is_none(),
3142 "A commitment transaction matched as both a counterparty and local commitment tx?");
3143 if !new_outputs.1.is_empty() {
3144 watch_outputs.push(new_outputs);
3146 claimable_outpoints.append(&mut new_outpoints);
3147 balance_spendable_csv = Some(self.on_holder_tx_csv);
3151 self.onchain_events_awaiting_threshold_conf.push(OnchainEventEntry {
3153 transaction: Some((*tx).clone()),
3155 block_hash: Some(block_hash),
3156 event: OnchainEvent::FundingSpendConfirmation {
3157 on_local_output_csv: balance_spendable_csv,
3158 commitment_tx_to_counterparty_output,
3163 if tx.input.len() >= 1 {
3164 // While all commitment transactions have one input, HTLC transactions may have more
3165 // if the HTLC was present in an anchor channel. HTLCs can also be resolved in a few
3166 // other ways which can have more than one output.
3167 for tx_input in &tx.input {
3168 let commitment_txid = tx_input.previous_output.txid;
3169 if let Some(&commitment_number) = self.counterparty_commitment_txn_on_chain.get(&commitment_txid) {
3170 let (mut new_outpoints, new_outputs_option) = self.check_spend_counterparty_htlc(
3171 &tx, commitment_number, &commitment_txid, height, &logger
3173 claimable_outpoints.append(&mut new_outpoints);
3174 if let Some(new_outputs) = new_outputs_option {
3175 watch_outputs.push(new_outputs);
3177 // Since there may be multiple HTLCs for this channel (all spending the
3178 // same commitment tx) being claimed by the counterparty within the same
3179 // transaction, and `check_spend_counterparty_htlc` already checks all the
3180 // ones relevant to this channel, we can safely break from our loop.
3184 self.is_resolving_htlc_output(&tx, height, &block_hash, &logger);
3186 self.is_paying_spendable_output(&tx, height, &block_hash, &logger);
3190 if height > self.best_block.height() {
3191 self.best_block = BestBlock::new(block_hash, height);
3194 self.block_confirmed(height, block_hash, txn_matched, watch_outputs, claimable_outpoints, &broadcaster, &fee_estimator, &logger)
3197 /// Update state for new block(s)/transaction(s) confirmed. Note that the caller must update
3198 /// `self.best_block` before calling if a new best blockchain tip is available. More
3199 /// concretely, `self.best_block` must never be at a lower height than `conf_height`, avoiding
3200 /// complexity especially in
3201 /// `OnchainTx::update_claims_view_from_requests`/`OnchainTx::update_claims_view_from_matched_txn`.
3203 /// `conf_height` should be set to the height at which any new transaction(s)/block(s) were
3204 /// confirmed at, even if it is not the current best height.
3205 fn block_confirmed<B: Deref, F: Deref, L: Deref>(
3208 conf_hash: BlockHash,
3209 txn_matched: Vec<&Transaction>,
3210 mut watch_outputs: Vec<TransactionOutputs>,
3211 mut claimable_outpoints: Vec<PackageTemplate>,
3213 fee_estimator: &LowerBoundedFeeEstimator<F>,
3215 ) -> Vec<TransactionOutputs>
3217 B::Target: BroadcasterInterface,
3218 F::Target: FeeEstimator,
3221 log_trace!(logger, "Processing {} matched transactions for block at height {}.", txn_matched.len(), conf_height);
3222 debug_assert!(self.best_block.height() >= conf_height);
3224 let should_broadcast = self.should_broadcast_holder_commitment_txn(logger);
3225 if should_broadcast {
3226 let funding_outp = HolderFundingOutput::build(self.funding_redeemscript.clone(), self.channel_value_satoshis, self.onchain_tx_handler.opt_anchors());
3227 let commitment_package = PackageTemplate::build_package(self.funding_info.0.txid.clone(), self.funding_info.0.index as u32, PackageSolvingData::HolderFundingOutput(funding_outp), self.best_block.height(), self.best_block.height());
3228 claimable_outpoints.push(commitment_package);
3229 self.pending_monitor_events.push(MonitorEvent::CommitmentTxConfirmed(self.funding_info.0));
3230 let commitment_tx = self.onchain_tx_handler.get_fully_signed_holder_tx(&self.funding_redeemscript);
3231 self.holder_tx_signed = true;
3232 // We can't broadcast our HTLC transactions while the commitment transaction is
3233 // unconfirmed. We'll delay doing so until we detect the confirmed commitment in
3234 // `transactions_confirmed`.
3235 if !self.onchain_tx_handler.opt_anchors() {
3236 // Because we're broadcasting a commitment transaction, we should construct the package
3237 // assuming it gets confirmed in the next block. Sadly, we have code which considers
3238 // "not yet confirmed" things as discardable, so we cannot do that here.
3239 let (mut new_outpoints, _) = self.get_broadcasted_holder_claims(&self.current_holder_commitment_tx, self.best_block.height());
3240 let new_outputs = self.get_broadcasted_holder_watch_outputs(&self.current_holder_commitment_tx, &commitment_tx);
3241 if !new_outputs.is_empty() {
3242 watch_outputs.push((self.current_holder_commitment_tx.txid.clone(), new_outputs));
3244 claimable_outpoints.append(&mut new_outpoints);
3248 // Find which on-chain events have reached their confirmation threshold.
3249 let onchain_events_awaiting_threshold_conf =
3250 self.onchain_events_awaiting_threshold_conf.drain(..).collect::<Vec<_>>();
3251 let mut onchain_events_reaching_threshold_conf = Vec::new();
3252 for entry in onchain_events_awaiting_threshold_conf {
3253 if entry.has_reached_confirmation_threshold(&self.best_block) {
3254 onchain_events_reaching_threshold_conf.push(entry);
3256 self.onchain_events_awaiting_threshold_conf.push(entry);
3260 // Used to check for duplicate HTLC resolutions.
3261 #[cfg(debug_assertions)]
3262 let unmatured_htlcs: Vec<_> = self.onchain_events_awaiting_threshold_conf
3264 .filter_map(|entry| match &entry.event {
3265 OnchainEvent::HTLCUpdate { source, .. } => Some(source),
3269 #[cfg(debug_assertions)]
3270 let mut matured_htlcs = Vec::new();
3272 // Produce actionable events from on-chain events having reached their threshold.
3273 for entry in onchain_events_reaching_threshold_conf.drain(..) {
3275 OnchainEvent::HTLCUpdate { ref source, payment_hash, htlc_value_satoshis, commitment_tx_output_idx } => {
3276 // Check for duplicate HTLC resolutions.
3277 #[cfg(debug_assertions)]
3280 unmatured_htlcs.iter().find(|&htlc| htlc == &source).is_none(),
3281 "An unmature HTLC transaction conflicts with a maturing one; failed to \
3282 call either transaction_unconfirmed for the conflicting transaction \
3283 or block_disconnected for a block containing it.");
3285 matured_htlcs.iter().find(|&htlc| htlc == source).is_none(),
3286 "A matured HTLC transaction conflicts with a maturing one; failed to \
3287 call either transaction_unconfirmed for the conflicting transaction \
3288 or block_disconnected for a block containing it.");
3289 matured_htlcs.push(source.clone());
3292 log_debug!(logger, "HTLC {} failure update in {} has got enough confirmations to be passed upstream",
3293 log_bytes!(payment_hash.0), entry.txid);
3294 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
3296 payment_preimage: None,
3297 source: source.clone(),
3298 htlc_value_satoshis,
3300 self.htlcs_resolved_on_chain.push(IrrevocablyResolvedHTLC {
3301 commitment_tx_output_idx,
3302 resolving_txid: Some(entry.txid),
3303 resolving_tx: entry.transaction,
3304 payment_preimage: None,
3307 OnchainEvent::MaturingOutput { descriptor } => {
3308 log_debug!(logger, "Descriptor {} has got enough confirmations to be passed upstream", log_spendable!(descriptor));
3309 self.pending_events.push(Event::SpendableOutputs {
3310 outputs: vec![descriptor]
3312 self.spendable_txids_confirmed.push(entry.txid);
3314 OnchainEvent::HTLCSpendConfirmation { commitment_tx_output_idx, preimage, .. } => {
3315 self.htlcs_resolved_on_chain.push(IrrevocablyResolvedHTLC {
3316 commitment_tx_output_idx: Some(commitment_tx_output_idx),
3317 resolving_txid: Some(entry.txid),
3318 resolving_tx: entry.transaction,
3319 payment_preimage: preimage,
3322 OnchainEvent::FundingSpendConfirmation { commitment_tx_to_counterparty_output, .. } => {
3323 self.funding_spend_confirmed = Some(entry.txid);
3324 self.confirmed_commitment_tx_counterparty_output = commitment_tx_to_counterparty_output;
3329 self.onchain_tx_handler.update_claims_view_from_requests(claimable_outpoints, conf_height, self.best_block.height(), broadcaster, fee_estimator, logger);
3330 self.onchain_tx_handler.update_claims_view_from_matched_txn(&txn_matched, conf_height, conf_hash, self.best_block.height(), broadcaster, fee_estimator, logger);
3332 // Determine new outputs to watch by comparing against previously known outputs to watch,
3333 // updating the latter in the process.
3334 watch_outputs.retain(|&(ref txid, ref txouts)| {
3335 let idx_and_scripts = txouts.iter().map(|o| (o.0, o.1.script_pubkey.clone())).collect();
3336 self.outputs_to_watch.insert(txid.clone(), idx_and_scripts).is_none()
3340 // If we see a transaction for which we registered outputs previously,
3341 // make sure the registered scriptpubkey at the expected index match
3342 // the actual transaction output one. We failed this case before #653.
3343 for tx in &txn_matched {
3344 if let Some(outputs) = self.get_outputs_to_watch().get(&tx.txid()) {
3345 for idx_and_script in outputs.iter() {
3346 assert!((idx_and_script.0 as usize) < tx.output.len());
3347 assert_eq!(tx.output[idx_and_script.0 as usize].script_pubkey, idx_and_script.1);
3355 pub fn block_disconnected<B: Deref, F: Deref, L: Deref>(&mut self, header: &BlockHeader, height: u32, broadcaster: B, fee_estimator: F, logger: L)
3356 where B::Target: BroadcasterInterface,
3357 F::Target: FeeEstimator,
3360 log_trace!(logger, "Block {} at height {} disconnected", header.block_hash(), height);
3363 //- htlc update there as failure-trigger tx (revoked commitment tx, non-revoked commitment tx, HTLC-timeout tx) has been disconnected
3364 //- maturing spendable output has transaction paying us has been disconnected
3365 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| entry.height < height);
3367 let bounded_fee_estimator = LowerBoundedFeeEstimator::new(fee_estimator);
3368 self.onchain_tx_handler.block_disconnected(height, broadcaster, &bounded_fee_estimator, logger);
3370 self.best_block = BestBlock::new(header.prev_blockhash, height - 1);
3373 fn transaction_unconfirmed<B: Deref, F: Deref, L: Deref>(
3377 fee_estimator: &LowerBoundedFeeEstimator<F>,
3380 B::Target: BroadcasterInterface,
3381 F::Target: FeeEstimator,
3384 let mut removed_height = None;
3385 for entry in self.onchain_events_awaiting_threshold_conf.iter() {
3386 if entry.txid == *txid {
3387 removed_height = Some(entry.height);
3392 if let Some(removed_height) = removed_height {
3393 log_info!(logger, "transaction_unconfirmed of txid {} implies height {} was reorg'd out", txid, removed_height);
3394 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| if entry.height >= removed_height {
3395 log_info!(logger, "Transaction {} reorg'd out", entry.txid);
3400 debug_assert!(!self.onchain_events_awaiting_threshold_conf.iter().any(|ref entry| entry.txid == *txid));
3402 self.onchain_tx_handler.transaction_unconfirmed(txid, broadcaster, fee_estimator, logger);
3405 /// Filters a block's `txdata` for transactions spending watched outputs or for any child
3406 /// transactions thereof.
3407 fn filter_block<'a>(&self, txdata: &TransactionData<'a>) -> Vec<&'a Transaction> {
3408 let mut matched_txn = HashSet::new();
3409 txdata.iter().filter(|&&(_, tx)| {
3410 let mut matches = self.spends_watched_output(tx);
3411 for input in tx.input.iter() {
3412 if matches { break; }
3413 if matched_txn.contains(&input.previous_output.txid) {
3418 matched_txn.insert(tx.txid());
3421 }).map(|(_, tx)| *tx).collect()
3424 /// Checks if a given transaction spends any watched outputs.
3425 fn spends_watched_output(&self, tx: &Transaction) -> bool {
3426 for input in tx.input.iter() {
3427 if let Some(outputs) = self.get_outputs_to_watch().get(&input.previous_output.txid) {
3428 for (idx, _script_pubkey) in outputs.iter() {
3429 if *idx == input.previous_output.vout {
3432 // If the expected script is a known type, check that the witness
3433 // appears to be spending the correct type (ie that the match would
3434 // actually succeed in BIP 158/159-style filters).
3435 if _script_pubkey.is_v0_p2wsh() {
3436 if input.witness.last().unwrap().to_vec() == deliberately_bogus_accepted_htlc_witness_program() {
3437 // In at least one test we use a deliberately bogus witness
3438 // script which hit an old panic. Thus, we check for that here
3439 // and avoid the assert if its the expected bogus script.
3443 assert_eq!(&bitcoin::Address::p2wsh(&Script::from(input.witness.last().unwrap().to_vec()), bitcoin::Network::Bitcoin).script_pubkey(), _script_pubkey);
3444 } else if _script_pubkey.is_v0_p2wpkh() {
3445 assert_eq!(&bitcoin::Address::p2wpkh(&bitcoin::PublicKey::from_slice(&input.witness.last().unwrap()).unwrap(), bitcoin::Network::Bitcoin).unwrap().script_pubkey(), _script_pubkey);
3446 } else { panic!(); }
3457 fn should_broadcast_holder_commitment_txn<L: Deref>(&self, logger: &L) -> bool where L::Target: Logger {
3458 // There's no need to broadcast our commitment transaction if we've seen one confirmed (even
3459 // with 1 confirmation) as it'll be rejected as duplicate/conflicting.
3460 if self.funding_spend_confirmed.is_some() ||
3461 self.onchain_events_awaiting_threshold_conf.iter().find(|event| match event.event {
3462 OnchainEvent::FundingSpendConfirmation { .. } => true,
3468 // We need to consider all HTLCs which are:
3469 // * in any unrevoked counterparty commitment transaction, as they could broadcast said
3470 // transactions and we'd end up in a race, or
3471 // * are in our latest holder commitment transaction, as this is the thing we will
3472 // broadcast if we go on-chain.
3473 // Note that we consider HTLCs which were below dust threshold here - while they don't
3474 // strictly imply that we need to fail the channel, we need to go ahead and fail them back
3475 // to the source, and if we don't fail the channel we will have to ensure that the next
3476 // updates that peer sends us are update_fails, failing the channel if not. It's probably
3477 // easier to just fail the channel as this case should be rare enough anyway.
3478 let height = self.best_block.height();
3479 macro_rules! scan_commitment {
3480 ($htlcs: expr, $holder_tx: expr) => {
3481 for ref htlc in $htlcs {
3482 // For inbound HTLCs which we know the preimage for, we have to ensure we hit the
3483 // chain with enough room to claim the HTLC without our counterparty being able to
3484 // time out the HTLC first.
3485 // For outbound HTLCs which our counterparty hasn't failed/claimed, our primary
3486 // concern is being able to claim the corresponding inbound HTLC (on another
3487 // channel) before it expires. In fact, we don't even really care if our
3488 // counterparty here claims such an outbound HTLC after it expired as long as we
3489 // can still claim the corresponding HTLC. Thus, to avoid needlessly hitting the
3490 // chain when our counterparty is waiting for expiration to off-chain fail an HTLC
3491 // we give ourselves a few blocks of headroom after expiration before going
3492 // on-chain for an expired HTLC.
3493 // Note that, to avoid a potential attack whereby a node delays claiming an HTLC
3494 // from us until we've reached the point where we go on-chain with the
3495 // corresponding inbound HTLC, we must ensure that outbound HTLCs go on chain at
3496 // least CLTV_CLAIM_BUFFER blocks prior to the inbound HTLC.
3497 // aka outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS == height - CLTV_CLAIM_BUFFER
3498 // inbound_cltv == height + CLTV_CLAIM_BUFFER
3499 // outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS + CLTV_CLAIM_BUFFER <= inbound_cltv - CLTV_CLAIM_BUFFER
3500 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= inbound_cltv - outbound_cltv
3501 // CLTV_EXPIRY_DELTA <= inbound_cltv - outbound_cltv (by check in ChannelManager::decode_update_add_htlc_onion)
3502 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= CLTV_EXPIRY_DELTA
3503 // The final, above, condition is checked for statically in channelmanager
3504 // with CHECK_CLTV_EXPIRY_SANITY_2.
3505 let htlc_outbound = $holder_tx == htlc.offered;
3506 if ( htlc_outbound && htlc.cltv_expiry + LATENCY_GRACE_PERIOD_BLOCKS <= height) ||
3507 (!htlc_outbound && htlc.cltv_expiry <= height + CLTV_CLAIM_BUFFER && self.payment_preimages.contains_key(&htlc.payment_hash)) {
3508 log_info!(logger, "Force-closing channel due to {} HTLC timeout, HTLC expiry is {}", if htlc_outbound { "outbound" } else { "inbound "}, htlc.cltv_expiry);
3515 scan_commitment!(self.current_holder_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, _)| a), true);
3517 if let Some(ref txid) = self.current_counterparty_commitment_txid {
3518 if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(txid) {
3519 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
3522 if let Some(ref txid) = self.prev_counterparty_commitment_txid {
3523 if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(txid) {
3524 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
3531 /// Check if any transaction broadcasted is resolving HTLC output by a success or timeout on a holder
3532 /// or counterparty commitment tx, if so send back the source, preimage if found and payment_hash of resolved HTLC
3533 fn is_resolving_htlc_output<L: Deref>(&mut self, tx: &Transaction, height: u32, block_hash: &BlockHash, logger: &L) where L::Target: Logger {
3534 'outer_loop: for input in &tx.input {
3535 let mut payment_data = None;
3536 let htlc_claim = HTLCClaim::from_witness(&input.witness);
3537 let revocation_sig_claim = htlc_claim == Some(HTLCClaim::Revocation);
3538 let accepted_preimage_claim = htlc_claim == Some(HTLCClaim::AcceptedPreimage);
3539 #[cfg(not(fuzzing))]
3540 let accepted_timeout_claim = htlc_claim == Some(HTLCClaim::AcceptedTimeout);
3541 let offered_preimage_claim = htlc_claim == Some(HTLCClaim::OfferedPreimage);
3542 #[cfg(not(fuzzing))]
3543 let offered_timeout_claim = htlc_claim == Some(HTLCClaim::OfferedTimeout);
3545 let mut payment_preimage = PaymentPreimage([0; 32]);
3546 if offered_preimage_claim || accepted_preimage_claim {
3547 payment_preimage.0.copy_from_slice(input.witness.second_to_last().unwrap());
3550 macro_rules! log_claim {
3551 ($tx_info: expr, $holder_tx: expr, $htlc: expr, $source_avail: expr) => {
3552 let outbound_htlc = $holder_tx == $htlc.offered;
3553 // HTLCs must either be claimed by a matching script type or through the
3555 #[cfg(not(fuzzing))] // Note that the fuzzer is not bound by pesky things like "signatures"
3556 debug_assert!(!$htlc.offered || offered_preimage_claim || offered_timeout_claim || revocation_sig_claim);
3557 #[cfg(not(fuzzing))] // Note that the fuzzer is not bound by pesky things like "signatures"
3558 debug_assert!($htlc.offered || accepted_preimage_claim || accepted_timeout_claim || revocation_sig_claim);
3559 // Further, only exactly one of the possible spend paths should have been
3560 // matched by any HTLC spend:
3561 #[cfg(not(fuzzing))] // Note that the fuzzer is not bound by pesky things like "signatures"
3562 debug_assert_eq!(accepted_preimage_claim as u8 + accepted_timeout_claim as u8 +
3563 offered_preimage_claim as u8 + offered_timeout_claim as u8 +
3564 revocation_sig_claim as u8, 1);
3565 if ($holder_tx && revocation_sig_claim) ||
3566 (outbound_htlc && !$source_avail && (accepted_preimage_claim || offered_preimage_claim)) {
3567 log_error!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}!",
3568 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
3569 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
3570 if revocation_sig_claim { "revocation sig" } else { "preimage claim after we'd passed the HTLC resolution back. We can likely claim the HTLC output with a revocation claim" });
3572 log_info!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}",
3573 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
3574 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
3575 if revocation_sig_claim { "revocation sig" } else if accepted_preimage_claim || offered_preimage_claim { "preimage" } else { "timeout" });
3580 macro_rules! check_htlc_valid_counterparty {
3581 ($counterparty_txid: expr, $htlc_output: expr) => {
3582 if let Some(txid) = $counterparty_txid {
3583 for &(ref pending_htlc, ref pending_source) in self.counterparty_claimable_outpoints.get(&txid).unwrap() {
3584 if pending_htlc.payment_hash == $htlc_output.payment_hash && pending_htlc.amount_msat == $htlc_output.amount_msat {
3585 if let &Some(ref source) = pending_source {
3586 log_claim!("revoked counterparty commitment tx", false, pending_htlc, true);
3587 payment_data = Some(((**source).clone(), $htlc_output.payment_hash, $htlc_output.amount_msat));
3596 macro_rules! scan_commitment {
3597 ($htlcs: expr, $tx_info: expr, $holder_tx: expr) => {
3598 for (ref htlc_output, source_option) in $htlcs {
3599 if Some(input.previous_output.vout) == htlc_output.transaction_output_index {
3600 if let Some(ref source) = source_option {
3601 log_claim!($tx_info, $holder_tx, htlc_output, true);
3602 // We have a resolution of an HTLC either from one of our latest
3603 // holder commitment transactions or an unrevoked counterparty commitment
3604 // transaction. This implies we either learned a preimage, the HTLC
3605 // has timed out, or we screwed up. In any case, we should now
3606 // resolve the source HTLC with the original sender.
3607 payment_data = Some(((*source).clone(), htlc_output.payment_hash, htlc_output.amount_msat));
3608 } else if !$holder_tx {
3609 check_htlc_valid_counterparty!(self.current_counterparty_commitment_txid, htlc_output);
3610 if payment_data.is_none() {
3611 check_htlc_valid_counterparty!(self.prev_counterparty_commitment_txid, htlc_output);
3614 if payment_data.is_none() {
3615 log_claim!($tx_info, $holder_tx, htlc_output, false);
3616 let outbound_htlc = $holder_tx == htlc_output.offered;
3617 self.onchain_events_awaiting_threshold_conf.push(OnchainEventEntry {
3618 txid: tx.txid(), height, block_hash: Some(*block_hash), transaction: Some(tx.clone()),
3619 event: OnchainEvent::HTLCSpendConfirmation {
3620 commitment_tx_output_idx: input.previous_output.vout,
3621 preimage: if accepted_preimage_claim || offered_preimage_claim {
3622 Some(payment_preimage) } else { None },
3623 // If this is a payment to us (ie !outbound_htlc), wait for
3624 // the CSV delay before dropping the HTLC from claimable
3625 // balance if the claim was an HTLC-Success transaction (ie
3626 // accepted_preimage_claim).
3627 on_to_local_output_csv: if accepted_preimage_claim && !outbound_htlc {
3628 Some(self.on_holder_tx_csv) } else { None },
3631 continue 'outer_loop;
3638 if input.previous_output.txid == self.current_holder_commitment_tx.txid {
3639 scan_commitment!(self.current_holder_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
3640 "our latest holder commitment tx", true);
3642 if let Some(ref prev_holder_signed_commitment_tx) = self.prev_holder_signed_commitment_tx {
3643 if input.previous_output.txid == prev_holder_signed_commitment_tx.txid {
3644 scan_commitment!(prev_holder_signed_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
3645 "our previous holder commitment tx", true);
3648 if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(&input.previous_output.txid) {
3649 scan_commitment!(htlc_outputs.iter().map(|&(ref a, ref b)| (a, (b.as_ref().clone()).map(|boxed| &**boxed))),
3650 "counterparty commitment tx", false);
3653 // Check that scan_commitment, above, decided there is some source worth relaying an
3654 // HTLC resolution backwards to and figure out whether we learned a preimage from it.
3655 if let Some((source, payment_hash, amount_msat)) = payment_data {
3656 if accepted_preimage_claim {
3657 if !self.pending_monitor_events.iter().any(
3658 |update| if let &MonitorEvent::HTLCEvent(ref upd) = update { upd.source == source } else { false }) {
3659 self.onchain_events_awaiting_threshold_conf.push(OnchainEventEntry {
3662 block_hash: Some(*block_hash),
3663 transaction: Some(tx.clone()),
3664 event: OnchainEvent::HTLCSpendConfirmation {
3665 commitment_tx_output_idx: input.previous_output.vout,
3666 preimage: Some(payment_preimage),
3667 on_to_local_output_csv: None,
3670 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
3672 payment_preimage: Some(payment_preimage),
3674 htlc_value_satoshis: Some(amount_msat / 1000),
3677 } else if offered_preimage_claim {
3678 if !self.pending_monitor_events.iter().any(
3679 |update| if let &MonitorEvent::HTLCEvent(ref upd) = update {
3680 upd.source == source
3682 self.onchain_events_awaiting_threshold_conf.push(OnchainEventEntry {
3684 transaction: Some(tx.clone()),
3686 block_hash: Some(*block_hash),
3687 event: OnchainEvent::HTLCSpendConfirmation {
3688 commitment_tx_output_idx: input.previous_output.vout,
3689 preimage: Some(payment_preimage),
3690 on_to_local_output_csv: None,
3693 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
3695 payment_preimage: Some(payment_preimage),
3697 htlc_value_satoshis: Some(amount_msat / 1000),
3701 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| {
3702 if entry.height != height { return true; }
3704 OnchainEvent::HTLCUpdate { source: ref htlc_source, .. } => {
3705 *htlc_source != source
3710 let entry = OnchainEventEntry {
3712 transaction: Some(tx.clone()),
3714 block_hash: Some(*block_hash),
3715 event: OnchainEvent::HTLCUpdate {
3716 source, payment_hash,
3717 htlc_value_satoshis: Some(amount_msat / 1000),
3718 commitment_tx_output_idx: Some(input.previous_output.vout),
3721 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());
3722 self.onchain_events_awaiting_threshold_conf.push(entry);
3728 /// Check if any transaction broadcasted is paying fund back to some address we can assume to own
3729 fn is_paying_spendable_output<L: Deref>(&mut self, tx: &Transaction, height: u32, block_hash: &BlockHash, logger: &L) where L::Target: Logger {
3730 let mut spendable_output = None;
3731 for (i, outp) in tx.output.iter().enumerate() { // There is max one spendable output for any channel tx, including ones generated by us
3732 if i > ::core::u16::MAX as usize {
3733 // While it is possible that an output exists on chain which is greater than the
3734 // 2^16th output in a given transaction, this is only possible if the output is not
3735 // in a lightning transaction and was instead placed there by some third party who
3736 // wishes to give us money for no reason.
3737 // Namely, any lightning transactions which we pre-sign will never have anywhere
3738 // near 2^16 outputs both because such transactions must have ~2^16 outputs who's
3739 // scripts are not longer than one byte in length and because they are inherently
3740 // non-standard due to their size.
3741 // Thus, it is completely safe to ignore such outputs, and while it may result in
3742 // us ignoring non-lightning fund to us, that is only possible if someone fills
3743 // nearly a full block with garbage just to hit this case.
3746 if outp.script_pubkey == self.destination_script {
3747 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
3748 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
3749 output: outp.clone(),
3753 if let Some(ref broadcasted_holder_revokable_script) = self.broadcasted_holder_revokable_script {
3754 if broadcasted_holder_revokable_script.0 == outp.script_pubkey {
3755 spendable_output = Some(SpendableOutputDescriptor::DelayedPaymentOutput(DelayedPaymentOutputDescriptor {
3756 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
3757 per_commitment_point: broadcasted_holder_revokable_script.1,
3758 to_self_delay: self.on_holder_tx_csv,
3759 output: outp.clone(),
3760 revocation_pubkey: broadcasted_holder_revokable_script.2.clone(),
3761 channel_keys_id: self.channel_keys_id,
3762 channel_value_satoshis: self.channel_value_satoshis,
3767 if self.counterparty_payment_script == outp.script_pubkey {
3768 spendable_output = Some(SpendableOutputDescriptor::StaticPaymentOutput(StaticPaymentOutputDescriptor {
3769 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
3770 output: outp.clone(),
3771 channel_keys_id: self.channel_keys_id,
3772 channel_value_satoshis: self.channel_value_satoshis,
3776 if self.shutdown_script.as_ref() == Some(&outp.script_pubkey) {
3777 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
3778 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
3779 output: outp.clone(),
3784 if let Some(spendable_output) = spendable_output {
3785 let entry = OnchainEventEntry {
3787 transaction: Some(tx.clone()),
3789 block_hash: Some(*block_hash),
3790 event: OnchainEvent::MaturingOutput { descriptor: spendable_output.clone() },
3792 log_info!(logger, "Received spendable output {}, spendable at height {}", log_spendable!(spendable_output), entry.confirmation_threshold());
3793 self.onchain_events_awaiting_threshold_conf.push(entry);
3798 impl<Signer: WriteableEcdsaChannelSigner, T: Deref, F: Deref, L: Deref> chain::Listen for (ChannelMonitor<Signer>, T, F, L)
3800 T::Target: BroadcasterInterface,
3801 F::Target: FeeEstimator,
3804 fn filtered_block_connected(&self, header: &BlockHeader, txdata: &TransactionData, height: u32) {
3805 self.0.block_connected(header, txdata, height, &*self.1, &*self.2, &*self.3);
3808 fn block_disconnected(&self, header: &BlockHeader, height: u32) {
3809 self.0.block_disconnected(header, height, &*self.1, &*self.2, &*self.3);
3813 impl<Signer: WriteableEcdsaChannelSigner, M, T: Deref, F: Deref, L: Deref> chain::Confirm for (M, T, F, L)
3815 M: Deref<Target = ChannelMonitor<Signer>>,
3816 T::Target: BroadcasterInterface,
3817 F::Target: FeeEstimator,
3820 fn transactions_confirmed(&self, header: &BlockHeader, txdata: &TransactionData, height: u32) {
3821 self.0.transactions_confirmed(header, txdata, height, &*self.1, &*self.2, &*self.3);
3824 fn transaction_unconfirmed(&self, txid: &Txid) {
3825 self.0.transaction_unconfirmed(txid, &*self.1, &*self.2, &*self.3);
3828 fn best_block_updated(&self, header: &BlockHeader, height: u32) {
3829 self.0.best_block_updated(header, height, &*self.1, &*self.2, &*self.3);
3832 fn get_relevant_txids(&self) -> Vec<(Txid, Option<BlockHash>)> {
3833 self.0.get_relevant_txids()
3837 const MAX_ALLOC_SIZE: usize = 64*1024;
3839 impl<'a, 'b, ES: EntropySource, SP: SignerProvider> ReadableArgs<(&'a ES, &'b SP)>
3840 for (BlockHash, ChannelMonitor<SP::Signer>) {
3841 fn read<R: io::Read>(reader: &mut R, args: (&'a ES, &'b SP)) -> Result<Self, DecodeError> {
3842 macro_rules! unwrap_obj {
3846 Err(_) => return Err(DecodeError::InvalidValue),
3851 let (entropy_source, signer_provider) = args;
3853 let _ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
3855 let latest_update_id: u64 = Readable::read(reader)?;
3856 let commitment_transaction_number_obscure_factor = <U48 as Readable>::read(reader)?.0;
3858 let destination_script = Readable::read(reader)?;
3859 let broadcasted_holder_revokable_script = match <u8 as Readable>::read(reader)? {
3861 let revokable_address = Readable::read(reader)?;
3862 let per_commitment_point = Readable::read(reader)?;
3863 let revokable_script = Readable::read(reader)?;
3864 Some((revokable_address, per_commitment_point, revokable_script))
3867 _ => return Err(DecodeError::InvalidValue),
3869 let counterparty_payment_script = Readable::read(reader)?;
3870 let shutdown_script = {
3871 let script = <Script as Readable>::read(reader)?;
3872 if script.is_empty() { None } else { Some(script) }
3875 let channel_keys_id = Readable::read(reader)?;
3876 let holder_revocation_basepoint = Readable::read(reader)?;
3877 // Technically this can fail and serialize fail a round-trip, but only for serialization of
3878 // barely-init'd ChannelMonitors that we can't do anything with.
3879 let outpoint = OutPoint {
3880 txid: Readable::read(reader)?,
3881 index: Readable::read(reader)?,
3883 let funding_info = (outpoint, Readable::read(reader)?);
3884 let current_counterparty_commitment_txid = Readable::read(reader)?;
3885 let prev_counterparty_commitment_txid = Readable::read(reader)?;
3887 let counterparty_commitment_params = Readable::read(reader)?;
3888 let funding_redeemscript = Readable::read(reader)?;
3889 let channel_value_satoshis = Readable::read(reader)?;
3891 let their_cur_per_commitment_points = {
3892 let first_idx = <U48 as Readable>::read(reader)?.0;
3896 let first_point = Readable::read(reader)?;
3897 let second_point_slice: [u8; 33] = Readable::read(reader)?;
3898 if second_point_slice[0..32] == [0; 32] && second_point_slice[32] == 0 {
3899 Some((first_idx, first_point, None))
3901 Some((first_idx, first_point, Some(unwrap_obj!(PublicKey::from_slice(&second_point_slice)))))
3906 let on_holder_tx_csv: u16 = Readable::read(reader)?;
3908 let commitment_secrets = Readable::read(reader)?;
3910 macro_rules! read_htlc_in_commitment {
3913 let offered: bool = Readable::read(reader)?;
3914 let amount_msat: u64 = Readable::read(reader)?;
3915 let cltv_expiry: u32 = Readable::read(reader)?;
3916 let payment_hash: PaymentHash = Readable::read(reader)?;
3917 let transaction_output_index: Option<u32> = Readable::read(reader)?;
3919 HTLCOutputInCommitment {
3920 offered, amount_msat, cltv_expiry, payment_hash, transaction_output_index
3926 let counterparty_claimable_outpoints_len: u64 = Readable::read(reader)?;
3927 let mut counterparty_claimable_outpoints = HashMap::with_capacity(cmp::min(counterparty_claimable_outpoints_len as usize, MAX_ALLOC_SIZE / 64));
3928 for _ in 0..counterparty_claimable_outpoints_len {
3929 let txid: Txid = Readable::read(reader)?;
3930 let htlcs_count: u64 = Readable::read(reader)?;
3931 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
3932 for _ in 0..htlcs_count {
3933 htlcs.push((read_htlc_in_commitment!(), <Option<HTLCSource> as Readable>::read(reader)?.map(|o: HTLCSource| Box::new(o))));
3935 if let Some(_) = counterparty_claimable_outpoints.insert(txid, htlcs) {
3936 return Err(DecodeError::InvalidValue);
3940 let counterparty_commitment_txn_on_chain_len: u64 = Readable::read(reader)?;
3941 let mut counterparty_commitment_txn_on_chain = HashMap::with_capacity(cmp::min(counterparty_commitment_txn_on_chain_len as usize, MAX_ALLOC_SIZE / 32));
3942 for _ in 0..counterparty_commitment_txn_on_chain_len {
3943 let txid: Txid = Readable::read(reader)?;
3944 let commitment_number = <U48 as Readable>::read(reader)?.0;
3945 if let Some(_) = counterparty_commitment_txn_on_chain.insert(txid, commitment_number) {
3946 return Err(DecodeError::InvalidValue);
3950 let counterparty_hash_commitment_number_len: u64 = Readable::read(reader)?;
3951 let mut counterparty_hash_commitment_number = HashMap::with_capacity(cmp::min(counterparty_hash_commitment_number_len as usize, MAX_ALLOC_SIZE / 32));
3952 for _ in 0..counterparty_hash_commitment_number_len {
3953 let payment_hash: PaymentHash = Readable::read(reader)?;
3954 let commitment_number = <U48 as Readable>::read(reader)?.0;
3955 if let Some(_) = counterparty_hash_commitment_number.insert(payment_hash, commitment_number) {
3956 return Err(DecodeError::InvalidValue);
3960 let mut prev_holder_signed_commitment_tx: Option<HolderSignedTx> =
3961 match <u8 as Readable>::read(reader)? {
3964 Some(Readable::read(reader)?)
3966 _ => return Err(DecodeError::InvalidValue),
3968 let mut current_holder_commitment_tx: HolderSignedTx = Readable::read(reader)?;
3970 let current_counterparty_commitment_number = <U48 as Readable>::read(reader)?.0;
3971 let current_holder_commitment_number = <U48 as Readable>::read(reader)?.0;
3973 let payment_preimages_len: u64 = Readable::read(reader)?;
3974 let mut payment_preimages = HashMap::with_capacity(cmp::min(payment_preimages_len as usize, MAX_ALLOC_SIZE / 32));
3975 for _ in 0..payment_preimages_len {
3976 let preimage: PaymentPreimage = Readable::read(reader)?;
3977 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
3978 if let Some(_) = payment_preimages.insert(hash, preimage) {
3979 return Err(DecodeError::InvalidValue);
3983 let pending_monitor_events_len: u64 = Readable::read(reader)?;
3984 let mut pending_monitor_events = Some(
3985 Vec::with_capacity(cmp::min(pending_monitor_events_len as usize, MAX_ALLOC_SIZE / (32 + 8*3))));
3986 for _ in 0..pending_monitor_events_len {
3987 let ev = match <u8 as Readable>::read(reader)? {
3988 0 => MonitorEvent::HTLCEvent(Readable::read(reader)?),
3989 1 => MonitorEvent::CommitmentTxConfirmed(funding_info.0),
3990 _ => return Err(DecodeError::InvalidValue)
3992 pending_monitor_events.as_mut().unwrap().push(ev);
3995 let pending_events_len: u64 = Readable::read(reader)?;
3996 let mut pending_events = Vec::with_capacity(cmp::min(pending_events_len as usize, MAX_ALLOC_SIZE / mem::size_of::<Event>()));
3997 for _ in 0..pending_events_len {
3998 if let Some(event) = MaybeReadable::read(reader)? {
3999 pending_events.push(event);
4003 let best_block = BestBlock::new(Readable::read(reader)?, Readable::read(reader)?);
4005 let waiting_threshold_conf_len: u64 = Readable::read(reader)?;
4006 let mut onchain_events_awaiting_threshold_conf = Vec::with_capacity(cmp::min(waiting_threshold_conf_len as usize, MAX_ALLOC_SIZE / 128));
4007 for _ in 0..waiting_threshold_conf_len {
4008 if let Some(val) = MaybeReadable::read(reader)? {
4009 onchain_events_awaiting_threshold_conf.push(val);
4013 let outputs_to_watch_len: u64 = Readable::read(reader)?;
4014 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>>())));
4015 for _ in 0..outputs_to_watch_len {
4016 let txid = Readable::read(reader)?;
4017 let outputs_len: u64 = Readable::read(reader)?;
4018 let mut outputs = Vec::with_capacity(cmp::min(outputs_len as usize, MAX_ALLOC_SIZE / (mem::size_of::<u32>() + mem::size_of::<Script>())));
4019 for _ in 0..outputs_len {
4020 outputs.push((Readable::read(reader)?, Readable::read(reader)?));
4022 if let Some(_) = outputs_to_watch.insert(txid, outputs) {
4023 return Err(DecodeError::InvalidValue);
4026 let onchain_tx_handler: OnchainTxHandler<SP::Signer> = ReadableArgs::read(
4027 reader, (entropy_source, signer_provider, channel_value_satoshis, channel_keys_id)
4030 let lockdown_from_offchain = Readable::read(reader)?;
4031 let holder_tx_signed = Readable::read(reader)?;
4033 if let Some(prev_commitment_tx) = prev_holder_signed_commitment_tx.as_mut() {
4034 let prev_holder_value = onchain_tx_handler.get_prev_holder_commitment_to_self_value();
4035 if prev_holder_value.is_none() { return Err(DecodeError::InvalidValue); }
4036 if prev_commitment_tx.to_self_value_sat == u64::max_value() {
4037 prev_commitment_tx.to_self_value_sat = prev_holder_value.unwrap();
4038 } else if prev_commitment_tx.to_self_value_sat != prev_holder_value.unwrap() {
4039 return Err(DecodeError::InvalidValue);
4043 let cur_holder_value = onchain_tx_handler.get_cur_holder_commitment_to_self_value();
4044 if current_holder_commitment_tx.to_self_value_sat == u64::max_value() {
4045 current_holder_commitment_tx.to_self_value_sat = cur_holder_value;
4046 } else if current_holder_commitment_tx.to_self_value_sat != cur_holder_value {
4047 return Err(DecodeError::InvalidValue);
4050 let mut funding_spend_confirmed = None;
4051 let mut htlcs_resolved_on_chain = Some(Vec::new());
4052 let mut funding_spend_seen = Some(false);
4053 let mut counterparty_node_id = None;
4054 let mut confirmed_commitment_tx_counterparty_output = None;
4055 let mut spendable_txids_confirmed = Some(Vec::new());
4056 let mut counterparty_fulfilled_htlcs = Some(HashMap::new());
4057 read_tlv_fields!(reader, {
4058 (1, funding_spend_confirmed, option),
4059 (3, htlcs_resolved_on_chain, vec_type),
4060 (5, pending_monitor_events, vec_type),
4061 (7, funding_spend_seen, option),
4062 (9, counterparty_node_id, option),
4063 (11, confirmed_commitment_tx_counterparty_output, option),
4064 (13, spendable_txids_confirmed, vec_type),
4065 (15, counterparty_fulfilled_htlcs, option),
4068 Ok((best_block.block_hash(), ChannelMonitor::from_impl(ChannelMonitorImpl {
4070 commitment_transaction_number_obscure_factor,
4073 broadcasted_holder_revokable_script,
4074 counterparty_payment_script,
4078 holder_revocation_basepoint,
4080 current_counterparty_commitment_txid,
4081 prev_counterparty_commitment_txid,
4083 counterparty_commitment_params,
4084 funding_redeemscript,
4085 channel_value_satoshis,
4086 their_cur_per_commitment_points,
4091 counterparty_claimable_outpoints,
4092 counterparty_commitment_txn_on_chain,
4093 counterparty_hash_commitment_number,
4094 counterparty_fulfilled_htlcs: counterparty_fulfilled_htlcs.unwrap(),
4096 prev_holder_signed_commitment_tx,
4097 current_holder_commitment_tx,
4098 current_counterparty_commitment_number,
4099 current_holder_commitment_number,
4102 pending_monitor_events: pending_monitor_events.unwrap(),
4105 onchain_events_awaiting_threshold_conf,
4110 lockdown_from_offchain,
4112 funding_spend_seen: funding_spend_seen.unwrap(),
4113 funding_spend_confirmed,
4114 confirmed_commitment_tx_counterparty_output,
4115 htlcs_resolved_on_chain: htlcs_resolved_on_chain.unwrap(),
4116 spendable_txids_confirmed: spendable_txids_confirmed.unwrap(),
4119 counterparty_node_id,
4126 use bitcoin::blockdata::script::{Script, Builder};
4127 use bitcoin::blockdata::opcodes;
4128 use bitcoin::blockdata::transaction::{Transaction, TxIn, TxOut, EcdsaSighashType};
4129 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
4130 use bitcoin::util::sighash;
4131 use bitcoin::hashes::Hash;
4132 use bitcoin::hashes::sha256::Hash as Sha256;
4133 use bitcoin::hashes::hex::FromHex;
4134 use bitcoin::hash_types::{BlockHash, Txid};
4135 use bitcoin::network::constants::Network;
4136 use bitcoin::secp256k1::{SecretKey,PublicKey};
4137 use bitcoin::secp256k1::Secp256k1;
4141 use crate::chain::chaininterface::LowerBoundedFeeEstimator;
4143 use super::ChannelMonitorUpdateStep;
4144 use crate::{check_added_monitors, check_closed_broadcast, check_closed_event, check_spends, get_local_commitment_txn, get_monitor, get_route_and_payment_hash, unwrap_send_err};
4145 use crate::chain::{BestBlock, Confirm};
4146 use crate::chain::channelmonitor::ChannelMonitor;
4147 use crate::chain::package::{weight_offered_htlc, weight_received_htlc, weight_revoked_offered_htlc, weight_revoked_received_htlc, WEIGHT_REVOKED_OUTPUT};
4148 use crate::chain::transaction::OutPoint;
4149 use crate::sign::InMemorySigner;
4150 use crate::events::ClosureReason;
4151 use crate::ln::{PaymentPreimage, PaymentHash};
4152 use crate::ln::chan_utils;
4153 use crate::ln::chan_utils::{HTLCOutputInCommitment, ChannelPublicKeys, ChannelTransactionParameters, HolderCommitmentTransaction, CounterpartyChannelTransactionParameters};
4154 use crate::ln::channelmanager::{PaymentSendFailure, PaymentId, RecipientOnionFields};
4155 use crate::ln::functional_test_utils::*;
4156 use crate::ln::script::ShutdownScript;
4157 use crate::util::errors::APIError;
4158 use crate::util::test_utils::{TestLogger, TestBroadcaster, TestFeeEstimator};
4159 use crate::util::ser::{ReadableArgs, Writeable};
4160 use crate::sync::{Arc, Mutex};
4162 use bitcoin::{PackedLockTime, Sequence, Witness};
4163 use crate::prelude::*;
4165 fn do_test_funding_spend_refuses_updates(use_local_txn: bool) {
4166 // Previously, monitor updates were allowed freely even after a funding-spend transaction
4167 // confirmed. This would allow a race condition where we could receive a payment (including
4168 // the counterparty revoking their broadcasted state!) and accept it without recourse as
4169 // long as the ChannelMonitor receives the block first, the full commitment update dance
4170 // occurs after the block is connected, and before the ChannelManager receives the block.
4171 // Obviously this is an incredibly contrived race given the counterparty would be risking
4172 // their full channel balance for it, but its worth fixing nonetheless as it makes the
4173 // potential ChannelMonitor states simpler to reason about.
4175 // This test checks said behavior, as well as ensuring a ChannelMonitorUpdate with multiple
4176 // updates is handled correctly in such conditions.
4177 let chanmon_cfgs = create_chanmon_cfgs(3);
4178 let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
4179 let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
4180 let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
4181 let channel = create_announced_chan_between_nodes(&nodes, 0, 1);
4182 create_announced_chan_between_nodes(&nodes, 1, 2);
4184 // Rebalance somewhat
4185 send_payment(&nodes[0], &[&nodes[1]], 10_000_000);
4187 // First route two payments for testing at the end
4188 let payment_preimage_1 = route_payment(&nodes[0], &[&nodes[1], &nodes[2]], 1_000_000).0;
4189 let payment_preimage_2 = route_payment(&nodes[0], &[&nodes[1], &nodes[2]], 1_000_000).0;
4191 let local_txn = get_local_commitment_txn!(nodes[1], channel.2);
4192 assert_eq!(local_txn.len(), 1);
4193 let remote_txn = get_local_commitment_txn!(nodes[0], channel.2);
4194 assert_eq!(remote_txn.len(), 3); // Commitment and two HTLC-Timeouts
4195 check_spends!(remote_txn[1], remote_txn[0]);
4196 check_spends!(remote_txn[2], remote_txn[0]);
4197 let broadcast_tx = if use_local_txn { &local_txn[0] } else { &remote_txn[0] };
4199 // Connect a commitment transaction, but only to the ChainMonitor/ChannelMonitor. The
4200 // channel is now closed, but the ChannelManager doesn't know that yet.
4201 let new_header = create_dummy_header(nodes[0].best_block_info().0, 0);
4202 let conf_height = nodes[0].best_block_info().1 + 1;
4203 nodes[1].chain_monitor.chain_monitor.transactions_confirmed(&new_header,
4204 &[(0, broadcast_tx)], conf_height);
4206 let (_, pre_update_monitor) = <(BlockHash, ChannelMonitor<InMemorySigner>)>::read(
4207 &mut io::Cursor::new(&get_monitor!(nodes[1], channel.2).encode()),
4208 (&nodes[1].keys_manager.backing, &nodes[1].keys_manager.backing)).unwrap();
4210 // If the ChannelManager tries to update the channel, however, the ChainMonitor will pass
4211 // the update through to the ChannelMonitor which will refuse it (as the channel is closed).
4212 let (route, payment_hash, _, payment_secret) = get_route_and_payment_hash!(nodes[1], nodes[0], 100_000);
4213 unwrap_send_err!(nodes[1].node.send_payment_with_route(&route, payment_hash,
4214 RecipientOnionFields::secret_only(payment_secret), PaymentId(payment_hash.0)
4215 ), true, APIError::ChannelUnavailable { ref err },
4216 assert!(err.contains("ChannelMonitor storage failure")));
4217 check_added_monitors!(nodes[1], 2); // After the failure we generate a close-channel monitor update
4218 check_closed_broadcast!(nodes[1], true);
4219 check_closed_event!(nodes[1], 1, ClosureReason::ProcessingError { err: "ChannelMonitor storage failure".to_string() });
4221 // Build a new ChannelMonitorUpdate which contains both the failing commitment tx update
4222 // and provides the claim preimages for the two pending HTLCs. The first update generates
4223 // an error, but the point of this test is to ensure the later updates are still applied.
4224 let monitor_updates = nodes[1].chain_monitor.monitor_updates.lock().unwrap();
4225 let mut replay_update = monitor_updates.get(&channel.2).unwrap().iter().rev().skip(1).next().unwrap().clone();
4226 assert_eq!(replay_update.updates.len(), 1);
4227 if let ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo { .. } = replay_update.updates[0] {
4228 } else { panic!(); }
4229 replay_update.updates.push(ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage: payment_preimage_1 });
4230 replay_update.updates.push(ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage: payment_preimage_2 });
4232 let broadcaster = TestBroadcaster::with_blocks(Arc::clone(&nodes[1].blocks));
4234 pre_update_monitor.update_monitor(&replay_update, &&broadcaster, &chanmon_cfgs[1].fee_estimator, &nodes[1].logger)
4236 // Even though we error'd on the first update, we should still have generated an HTLC claim
4238 let txn_broadcasted = broadcaster.txn_broadcasted.lock().unwrap().split_off(0);
4239 assert!(txn_broadcasted.len() >= 2);
4240 let htlc_txn = txn_broadcasted.iter().filter(|tx| {
4241 assert_eq!(tx.input.len(), 1);
4242 tx.input[0].previous_output.txid == broadcast_tx.txid()
4243 }).collect::<Vec<_>>();
4244 assert_eq!(htlc_txn.len(), 2);
4245 check_spends!(htlc_txn[0], broadcast_tx);
4246 check_spends!(htlc_txn[1], broadcast_tx);
4249 fn test_funding_spend_refuses_updates() {
4250 do_test_funding_spend_refuses_updates(true);
4251 do_test_funding_spend_refuses_updates(false);
4255 fn test_prune_preimages() {
4256 let secp_ctx = Secp256k1::new();
4257 let logger = Arc::new(TestLogger::new());
4258 let broadcaster = Arc::new(TestBroadcaster::new(Network::Testnet));
4259 let fee_estimator = TestFeeEstimator { sat_per_kw: Mutex::new(253) };
4261 let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
4263 let mut preimages = Vec::new();
4266 let preimage = PaymentPreimage([i; 32]);
4267 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
4268 preimages.push((preimage, hash));
4272 macro_rules! preimages_slice_to_htlcs {
4273 ($preimages_slice: expr) => {
4275 let mut res = Vec::new();
4276 for (idx, preimage) in $preimages_slice.iter().enumerate() {
4277 res.push((HTLCOutputInCommitment {
4281 payment_hash: preimage.1.clone(),
4282 transaction_output_index: Some(idx as u32),
4289 macro_rules! preimages_slice_to_htlc_outputs {
4290 ($preimages_slice: expr) => {
4291 preimages_slice_to_htlcs!($preimages_slice).into_iter().map(|(htlc, _)| (htlc, None)).collect()
4294 let dummy_sig = crate::util::crypto::sign(&secp_ctx,
4295 &bitcoin::secp256k1::Message::from_slice(&[42; 32]).unwrap(),
4296 &SecretKey::from_slice(&[42; 32]).unwrap());
4298 macro_rules! test_preimages_exist {
4299 ($preimages_slice: expr, $monitor: expr) => {
4300 for preimage in $preimages_slice {
4301 assert!($monitor.inner.lock().unwrap().payment_preimages.contains_key(&preimage.1));
4306 let keys = InMemorySigner::new(
4308 SecretKey::from_slice(&[41; 32]).unwrap(),
4309 SecretKey::from_slice(&[41; 32]).unwrap(),
4310 SecretKey::from_slice(&[41; 32]).unwrap(),
4311 SecretKey::from_slice(&[41; 32]).unwrap(),
4312 SecretKey::from_slice(&[41; 32]).unwrap(),
4319 let counterparty_pubkeys = ChannelPublicKeys {
4320 funding_pubkey: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[44; 32]).unwrap()),
4321 revocation_basepoint: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()),
4322 payment_point: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[46; 32]).unwrap()),
4323 delayed_payment_basepoint: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[47; 32]).unwrap()),
4324 htlc_basepoint: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[48; 32]).unwrap())
4326 let funding_outpoint = OutPoint { txid: Txid::all_zeros(), index: u16::max_value() };
4327 let channel_parameters = ChannelTransactionParameters {
4328 holder_pubkeys: keys.holder_channel_pubkeys.clone(),
4329 holder_selected_contest_delay: 66,
4330 is_outbound_from_holder: true,
4331 counterparty_parameters: Some(CounterpartyChannelTransactionParameters {
4332 pubkeys: counterparty_pubkeys,
4333 selected_contest_delay: 67,
4335 funding_outpoint: Some(funding_outpoint),
4337 opt_non_zero_fee_anchors: None,
4339 // Prune with one old state and a holder commitment tx holding a few overlaps with the
4341 let shutdown_pubkey = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
4342 let best_block = BestBlock::from_network(Network::Testnet);
4343 let monitor = ChannelMonitor::new(Secp256k1::new(), keys,
4344 Some(ShutdownScript::new_p2wpkh_from_pubkey(shutdown_pubkey).into_inner()), 0, &Script::new(),
4345 (OutPoint { txid: Txid::from_slice(&[43; 32]).unwrap(), index: 0 }, Script::new()),
4346 &channel_parameters, Script::new(), 46, 0, HolderCommitmentTransaction::dummy(&mut Vec::new()),
4347 best_block, dummy_key);
4349 let mut htlcs = preimages_slice_to_htlcs!(preimages[0..10]);
4350 let dummy_commitment_tx = HolderCommitmentTransaction::dummy(&mut htlcs);
4351 monitor.provide_latest_holder_commitment_tx(dummy_commitment_tx.clone(),
4352 htlcs.into_iter().map(|(htlc, _)| (htlc, Some(dummy_sig), None)).collect()).unwrap();
4353 monitor.provide_latest_counterparty_commitment_tx(Txid::from_inner(Sha256::hash(b"1").into_inner()),
4354 preimages_slice_to_htlc_outputs!(preimages[5..15]), 281474976710655, dummy_key, &logger);
4355 monitor.provide_latest_counterparty_commitment_tx(Txid::from_inner(Sha256::hash(b"2").into_inner()),
4356 preimages_slice_to_htlc_outputs!(preimages[15..20]), 281474976710654, dummy_key, &logger);
4357 for &(ref preimage, ref hash) in preimages.iter() {
4358 let bounded_fee_estimator = LowerBoundedFeeEstimator::new(&fee_estimator);
4359 monitor.provide_payment_preimage(hash, preimage, &broadcaster, &bounded_fee_estimator, &logger);
4362 // Now provide a secret, pruning preimages 10-15
4363 let mut secret = [0; 32];
4364 secret[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
4365 monitor.provide_secret(281474976710655, secret.clone()).unwrap();
4366 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 15);
4367 test_preimages_exist!(&preimages[0..10], monitor);
4368 test_preimages_exist!(&preimages[15..20], monitor);
4370 monitor.provide_latest_counterparty_commitment_tx(Txid::from_inner(Sha256::hash(b"3").into_inner()),
4371 preimages_slice_to_htlc_outputs!(preimages[17..20]), 281474976710653, dummy_key, &logger);
4373 // Now provide a further secret, pruning preimages 15-17
4374 secret[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
4375 monitor.provide_secret(281474976710654, secret.clone()).unwrap();
4376 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 13);
4377 test_preimages_exist!(&preimages[0..10], monitor);
4378 test_preimages_exist!(&preimages[17..20], monitor);
4380 monitor.provide_latest_counterparty_commitment_tx(Txid::from_inner(Sha256::hash(b"4").into_inner()),
4381 preimages_slice_to_htlc_outputs!(preimages[18..20]), 281474976710652, dummy_key, &logger);
4383 // Now update holder commitment tx info, pruning only element 18 as we still care about the
4384 // previous commitment tx's preimages too
4385 let mut htlcs = preimages_slice_to_htlcs!(preimages[0..5]);
4386 let dummy_commitment_tx = HolderCommitmentTransaction::dummy(&mut htlcs);
4387 monitor.provide_latest_holder_commitment_tx(dummy_commitment_tx.clone(),
4388 htlcs.into_iter().map(|(htlc, _)| (htlc, Some(dummy_sig), None)).collect()).unwrap();
4389 secret[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
4390 monitor.provide_secret(281474976710653, secret.clone()).unwrap();
4391 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 12);
4392 test_preimages_exist!(&preimages[0..10], monitor);
4393 test_preimages_exist!(&preimages[18..20], monitor);
4395 // But if we do it again, we'll prune 5-10
4396 let mut htlcs = preimages_slice_to_htlcs!(preimages[0..3]);
4397 let dummy_commitment_tx = HolderCommitmentTransaction::dummy(&mut htlcs);
4398 monitor.provide_latest_holder_commitment_tx(dummy_commitment_tx,
4399 htlcs.into_iter().map(|(htlc, _)| (htlc, Some(dummy_sig), None)).collect()).unwrap();
4400 secret[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
4401 monitor.provide_secret(281474976710652, secret.clone()).unwrap();
4402 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 5);
4403 test_preimages_exist!(&preimages[0..5], monitor);
4407 fn test_claim_txn_weight_computation() {
4408 // We test Claim txn weight, knowing that we want expected weigth and
4409 // not actual case to avoid sigs and time-lock delays hell variances.
4411 let secp_ctx = Secp256k1::new();
4412 let privkey = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
4413 let pubkey = PublicKey::from_secret_key(&secp_ctx, &privkey);
4415 macro_rules! sign_input {
4416 ($sighash_parts: expr, $idx: expr, $amount: expr, $weight: expr, $sum_actual_sigs: expr, $opt_anchors: expr) => {
4417 let htlc = HTLCOutputInCommitment {
4418 offered: if *$weight == weight_revoked_offered_htlc($opt_anchors) || *$weight == weight_offered_htlc($opt_anchors) { true } else { false },
4420 cltv_expiry: 2 << 16,
4421 payment_hash: PaymentHash([1; 32]),
4422 transaction_output_index: Some($idx as u32),
4424 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, $opt_anchors, &pubkey, &pubkey, &pubkey) };
4425 let sighash = hash_to_message!(&$sighash_parts.segwit_signature_hash($idx, &redeem_script, $amount, EcdsaSighashType::All).unwrap()[..]);
4426 let sig = secp_ctx.sign_ecdsa(&sighash, &privkey);
4427 let mut ser_sig = sig.serialize_der().to_vec();
4428 ser_sig.push(EcdsaSighashType::All as u8);
4429 $sum_actual_sigs += ser_sig.len();
4430 let witness = $sighash_parts.witness_mut($idx).unwrap();
4431 witness.push(ser_sig);
4432 if *$weight == WEIGHT_REVOKED_OUTPUT {
4433 witness.push(vec!(1));
4434 } else if *$weight == weight_revoked_offered_htlc($opt_anchors) || *$weight == weight_revoked_received_htlc($opt_anchors) {
4435 witness.push(pubkey.clone().serialize().to_vec());
4436 } else if *$weight == weight_received_htlc($opt_anchors) {
4437 witness.push(vec![0]);
4439 witness.push(PaymentPreimage([1; 32]).0.to_vec());
4441 witness.push(redeem_script.into_bytes());
4442 let witness = witness.to_vec();
4443 println!("witness[0] {}", witness[0].len());
4444 println!("witness[1] {}", witness[1].len());
4445 println!("witness[2] {}", witness[2].len());
4449 let script_pubkey = Builder::new().push_opcode(opcodes::all::OP_RETURN).into_script();
4450 let txid = Txid::from_hex("56944c5d3f98413ef45cf54545538103cc9f298e0575820ad3591376e2e0f65d").unwrap();
4452 // Justice tx with 1 to_holder, 2 revoked offered HTLCs, 1 revoked received HTLCs
4453 for &opt_anchors in [false, true].iter() {
4454 let mut claim_tx = Transaction { version: 0, lock_time: PackedLockTime::ZERO, input: Vec::new(), output: Vec::new() };
4455 let mut sum_actual_sigs = 0;
4457 claim_tx.input.push(TxIn {
4458 previous_output: BitcoinOutPoint {
4462 script_sig: Script::new(),
4463 sequence: Sequence::ENABLE_RBF_NO_LOCKTIME,
4464 witness: Witness::new(),
4467 claim_tx.output.push(TxOut {
4468 script_pubkey: script_pubkey.clone(),
4471 let base_weight = claim_tx.weight();
4472 let inputs_weight = vec![WEIGHT_REVOKED_OUTPUT, weight_revoked_offered_htlc(opt_anchors), weight_revoked_offered_htlc(opt_anchors), weight_revoked_received_htlc(opt_anchors)];
4473 let mut inputs_total_weight = 2; // count segwit flags
4475 let mut sighash_parts = sighash::SighashCache::new(&mut claim_tx);
4476 for (idx, inp) in inputs_weight.iter().enumerate() {
4477 sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs, opt_anchors);
4478 inputs_total_weight += inp;
4481 assert_eq!(base_weight + inputs_total_weight as usize, claim_tx.weight() + /* max_length_sig */ (73 * inputs_weight.len() - sum_actual_sigs));
4484 // Claim tx with 1 offered HTLCs, 3 received HTLCs
4485 for &opt_anchors in [false, true].iter() {
4486 let mut claim_tx = Transaction { version: 0, lock_time: PackedLockTime::ZERO, input: Vec::new(), output: Vec::new() };
4487 let mut sum_actual_sigs = 0;
4489 claim_tx.input.push(TxIn {
4490 previous_output: BitcoinOutPoint {
4494 script_sig: Script::new(),
4495 sequence: Sequence::ENABLE_RBF_NO_LOCKTIME,
4496 witness: Witness::new(),
4499 claim_tx.output.push(TxOut {
4500 script_pubkey: script_pubkey.clone(),
4503 let base_weight = claim_tx.weight();
4504 let inputs_weight = vec![weight_offered_htlc(opt_anchors), weight_received_htlc(opt_anchors), weight_received_htlc(opt_anchors), weight_received_htlc(opt_anchors)];
4505 let mut inputs_total_weight = 2; // count segwit flags
4507 let mut sighash_parts = sighash::SighashCache::new(&mut claim_tx);
4508 for (idx, inp) in inputs_weight.iter().enumerate() {
4509 sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs, opt_anchors);
4510 inputs_total_weight += inp;
4513 assert_eq!(base_weight + inputs_total_weight as usize, claim_tx.weight() + /* max_length_sig */ (73 * inputs_weight.len() - sum_actual_sigs));
4516 // Justice tx with 1 revoked HTLC-Success tx output
4517 for &opt_anchors in [false, true].iter() {
4518 let mut claim_tx = Transaction { version: 0, lock_time: PackedLockTime::ZERO, input: Vec::new(), output: Vec::new() };
4519 let mut sum_actual_sigs = 0;
4520 claim_tx.input.push(TxIn {
4521 previous_output: BitcoinOutPoint {
4525 script_sig: Script::new(),
4526 sequence: Sequence::ENABLE_RBF_NO_LOCKTIME,
4527 witness: Witness::new(),
4529 claim_tx.output.push(TxOut {
4530 script_pubkey: script_pubkey.clone(),
4533 let base_weight = claim_tx.weight();
4534 let inputs_weight = vec![WEIGHT_REVOKED_OUTPUT];
4535 let mut inputs_total_weight = 2; // count segwit flags
4537 let mut sighash_parts = sighash::SighashCache::new(&mut claim_tx);
4538 for (idx, inp) in inputs_weight.iter().enumerate() {
4539 sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs, opt_anchors);
4540 inputs_total_weight += inp;
4543 assert_eq!(base_weight + inputs_total_weight as usize, claim_tx.weight() + /* max_length_isg */ (73 * inputs_weight.len() - sum_actual_sigs));
4547 // Further testing is done in the ChannelManager integration tests.