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Merge pull request #2148 from TheBlueMatt/2023-04-claim-from-closed
[rust-lightning] / lightning / src / chain / channelmonitor.rs
1 // This file is Copyright its original authors, visible in version control
2 // history.
3 //
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
8 // licenses.
9
10 //! The logic to monitor for on-chain transactions and create the relevant claim responses lives
11 //! here.
12 //!
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.
16 //!
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 latest ChannelMonitor must always be actively monitoring for chain updates (and no out-of-date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.
22
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;
27
28 use bitcoin::hashes::Hash;
29 use bitcoin::hashes::sha256::Hash as Sha256;
30 use bitcoin::hash_types::{Txid, BlockHash, WPubkeyHash};
31
32 use bitcoin::secp256k1::{Secp256k1, ecdsa::Signature};
33 use bitcoin::secp256k1::{SecretKey, PublicKey};
34 use bitcoin::secp256k1;
35
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};
41 use crate::chain;
42 use crate::chain::{BestBlock, WatchedOutput};
43 use crate::chain::chaininterface::{BroadcasterInterface, FeeEstimator, LowerBoundedFeeEstimator};
44 use crate::chain::transaction::{OutPoint, TransactionData};
45 use crate::chain::keysinterface::{SpendableOutputDescriptor, StaticPaymentOutputDescriptor, DelayedPaymentOutputDescriptor, WriteableEcdsaChannelSigner, SignerProvider, EntropySource};
46 #[cfg(anchors)]
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;
55 #[cfg(anchors)]
56 use crate::events::bump_transaction::{AnchorDescriptor, HTLCDescriptor, BumpTransactionEvent};
57
58 use crate::prelude::*;
59 use core::{cmp, mem};
60 use crate::io::{self, Error};
61 use core::convert::TryInto;
62 use core::ops::Deref;
63 use crate::sync::{Mutex, LockTestExt};
64
65 /// An update generated by the underlying channel itself which contains some new information the
66 /// [`ChannelMonitor`] should be made aware of.
67 ///
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)]
73 #[must_use]
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.
79         ///
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.
83         ///
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.
89         ///
90         /// [`ChannelMonitorUpdateStatus::InProgress`]: super::ChannelMonitorUpdateStatus::InProgress
91         pub update_id: u64,
92 }
93
94 /// The update ID used for a [`ChannelMonitorUpdate`] that is either:
95 ///
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.
100 ///
101 /// No other [`ChannelMonitorUpdate`]s are allowed after force-close.
102 pub const CLOSED_CHANNEL_UPDATE_ID: u64 = core::u64::MAX;
103
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)?;
111                 }
112                 write_tlv_fields!(w, {});
113                 Ok(())
114         }
115 }
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>()));
122                 for _ in 0..len {
123                         if let Some(upd) = MaybeReadable::read(r)? {
124                                 updates.push(upd);
125                         }
126                 }
127                 read_tlv_fields!(r, {});
128                 Ok(Self { update_id, updates })
129         }
130 }
131
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),
137
138         /// A monitor event that the Channel's commitment transaction was confirmed.
139         CommitmentTxConfirmed(OutPoint),
140
141         /// Indicates a [`ChannelMonitor`] update has completed. See
142         /// [`ChannelMonitorUpdateStatus::InProgress`] for more information on how this is used.
143         ///
144         /// [`ChannelMonitorUpdateStatus::InProgress`]: super::ChannelMonitorUpdateStatus::InProgress
145         Completed {
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`].
150                 ///
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,
154         },
155
156         /// Indicates a [`ChannelMonitor`] update has failed. See
157         /// [`ChannelMonitorUpdateStatus::PermanentFailure`] for more information on how this is used.
158         ///
159         /// [`ChannelMonitorUpdateStatus::PermanentFailure`]: super::ChannelMonitorUpdateStatus::PermanentFailure
160         UpdateFailed(OutPoint),
161 }
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
165         (0, Completed) => {
166                 (0, funding_txo, required),
167                 (2, monitor_update_id, required),
168         },
169 ;
170         (2, HTLCEvent),
171         (4, CommitmentTxConfirmed),
172         (6, UpdateFailed),
173 );
174
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>,
184 }
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),
190 });
191
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
215 /// losing money.
216 ///
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.
227 ///
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
231 ///    fail this HTLC,
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,
234 ///
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.
237 ///
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;
242
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
247         txid: Txid,
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,
255         feerate_per_kw: u32,
256 }
257 impl_writeable_tlv_based!(HolderSignedTx, {
258         (0, txid, required),
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)
269 });
270
271 #[cfg(anchors)]
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 {
276                                 Some(htlc.clone())
277                         } else {
278                                 None
279                         }
280                 })
281                 .collect()
282         }
283 }
284
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,
292 }
293
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),
301                 });
302                 Ok(())
303         }
304 }
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)?;
316                                 }
317                         }
318
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),
326                         });
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,
331                         }
332                 };
333                 Ok(counterparty_commitment_transaction)
334         }
335 }
336
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.
339 ///
340 /// Used to determine when the on-chain event can be considered safe from a chain reorganization.
341 #[derive(PartialEq, Eq)]
342 struct OnchainEventEntry {
343         txid: Txid,
344         height: u32,
345         block_hash: Option<BlockHash>, // Added as optional, will be filled in for any entry generated on 0.0.113 or after
346         event: OnchainEvent,
347         transaction: Option<Transaction>, // Added as optional, but always filled in, in LDK 0.0.110
348 }
349
350 impl OnchainEventEntry {
351         fn confirmation_threshold(&self) -> u32 {
352                 let mut conf_threshold = self.height + ANTI_REORG_DELAY - 1;
353                 match self.event {
354                         OnchainEvent::MaturingOutput {
355                                 descriptor: SpendableOutputDescriptor::DelayedPaymentOutput(ref descriptor)
356                         } => {
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);
360                         },
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);
366                         },
367                         _ => {},
368                 }
369                 conf_threshold
370         }
371
372         fn has_reached_confirmation_threshold(&self, best_block: &BestBlock) -> bool {
373                 best_block.height() >= self.confirmation_threshold()
374         }
375 }
376
377 /// The (output index, sats value) for the counterparty's output in a commitment transaction.
378 ///
379 /// This was added as an `Option` in 0.0.110.
380 type CommitmentTxCounterpartyOutputInfo = Option<(u32, u64)>;
381
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)]
385 enum OnchainEvent {
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.
392         HTLCUpdate {
393                 source: HTLCSource,
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>,
399         },
400         /// An output waiting on [`ANTI_REORG_DELAY`] confirmations before we hand the user the
401         /// [`SpendableOutputDescriptor`].
402         MaturingOutput {
403                 descriptor: SpendableOutputDescriptor,
404         },
405         /// A spend of the funding output, either a commitment transaction or a cooperative closing
406         /// transaction.
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.
413                 ///
414                 /// This allows us to generate a [`Balance::CounterpartyRevokedOutputClaimable`] for the
415                 /// counterparty output.
416                 commitment_tx_to_counterparty_output: CommitmentTxCounterpartyOutputInfo,
417         },
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
425         ///    signature.
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
428         ///    signature).
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>,
437         },
438 }
439
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),
448                 });
449                 Ok(())
450         }
451 }
452
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;
458                 let mut height = 0;
459                 let mut event = UpgradableRequired(None);
460                 read_tlv_fields!(reader, {
461                         (0, txid, required),
462                         (1, transaction, option),
463                         (2, height, required),
464                         (3, block_hash, option),
465                         (4, event, upgradable_required),
466                 });
467                 Ok(Some(Self { txid, transaction, height, block_hash, event: _init_tlv_based_struct_field!(event, upgradable_required) }))
468         }
469 }
470
471 impl_writeable_tlv_based_enum_upgradable!(OnchainEvent,
472         (0, HTLCUpdate) => {
473                 (0, source, required),
474                 (1, htlc_value_satoshis, option),
475                 (2, payment_hash, required),
476                 (3, commitment_tx_output_idx, option),
477         },
478         (1, MaturingOutput) => {
479                 (0, descriptor, required),
480         },
481         (3, FundingSpendConfirmation) => {
482                 (0, on_local_output_csv, option),
483                 (1, commitment_tx_to_counterparty_output, option),
484         },
485         (5, HTLCSpendConfirmation) => {
486                 (0, commitment_tx_output_idx, required),
487                 (2, preimage, option),
488                 (4, on_to_local_output_csv, option),
489         },
490
491 );
492
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>,
503         },
504         LatestCounterpartyCommitmentTXInfo {
505                 commitment_txid: Txid,
506                 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
507                 commitment_number: u64,
508                 their_per_commitment_point: PublicKey,
509         },
510         PaymentPreimage {
511                 payment_preimage: PaymentPreimage,
512         },
513         CommitmentSecret {
514                 idx: u64,
515                 secret: [u8; 32],
516         },
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.
519         ChannelForceClosed {
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,
523         },
524         ShutdownScript {
525                 scriptpubkey: Script,
526         },
527 }
528
529 impl ChannelMonitorUpdateStep {
530         fn variant_name(&self) -> &'static str {
531                 match self {
532                         ChannelMonitorUpdateStep::LatestHolderCommitmentTXInfo { .. } => "LatestHolderCommitmentTXInfo",
533                         ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo { .. } => "LatestCounterpartyCommitmentTXInfo",
534                         ChannelMonitorUpdateStep::PaymentPreimage { .. } => "PaymentPreimage",
535                         ChannelMonitorUpdateStep::CommitmentSecret { .. } => "CommitmentSecret",
536                         ChannelMonitorUpdateStep::ChannelForceClosed { .. } => "ChannelForceClosed",
537                         ChannelMonitorUpdateStep::ShutdownScript { .. } => "ShutdownScript",
538                 }
539         }
540 }
541
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),
548         },
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),
554         },
555         (2, PaymentPreimage) => {
556                 (0, payment_preimage, required),
557         },
558         (3, CommitmentSecret) => {
559                 (0, idx, required),
560                 (2, secret, required),
561         },
562         (4, ChannelForceClosed) => {
563                 (0, should_broadcast, required),
564         },
565         (5, ShutdownScript) => {
566                 (0, scriptpubkey, required),
567         },
568 );
569
570 /// Details about the balance(s) available for spending once the channel appears on chain.
571 ///
572 /// See [`ChannelMonitor::get_claimable_balances`] for more details on when these will or will not
573 /// be provided.
574 #[derive(Clone, Debug, PartialEq, Eq)]
575 #[cfg_attr(test, derive(PartialOrd, Ord))]
576 pub enum Balance {
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,
584         },
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
592                 /// amount.
593                 confirmation_height: u32,
594         },
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.
598         ///
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
607                 /// done so.
608                 timeout_height: u32,
609         },
610         /// HTLCs which we sent to our counterparty which are claimable after a timeout (less on-chain
611         /// fees) if the counterparty does not know the preimage for the HTLCs. These are somewhat
612         /// likely to be claimed by our counterparty before we do.
613         MaybeTimeoutClaimableHTLC {
614                 /// The amount potentially available to claim, in satoshis, excluding the on-chain fees
615                 /// which will be required to do so.
616                 claimable_amount_satoshis: u64,
617                 /// The height at which we will be able to claim the balance if our counterparty has not
618                 /// done so.
619                 claimable_height: u32,
620         },
621         /// HTLCs which we received from our counterparty which are claimable with a preimage which we
622         /// do not currently have. This will only be claimable if we receive the preimage from the node
623         /// to which we forwarded this HTLC before the timeout.
624         MaybePreimageClaimableHTLC {
625                 /// The amount potentially available to claim, in satoshis, excluding the on-chain fees
626                 /// which will be required to do so.
627                 claimable_amount_satoshis: u64,
628                 /// The height at which our counterparty will be able to claim the balance if we have not
629                 /// yet received the preimage and claimed it ourselves.
630                 expiry_height: u32,
631         },
632         /// The channel has been closed, and our counterparty broadcasted a revoked commitment
633         /// transaction.
634         ///
635         /// Thus, we're able to claim all outputs in the commitment transaction, one of which has the
636         /// following amount.
637         CounterpartyRevokedOutputClaimable {
638                 /// The amount, in satoshis, of the output which we can claim.
639                 ///
640                 /// Note that for outputs from HTLC balances this may be excluding some on-chain fees that
641                 /// were already spent.
642                 claimable_amount_satoshis: u64,
643         },
644 }
645
646 /// An HTLC which has been irrevocably resolved on-chain, and has reached ANTI_REORG_DELAY.
647 #[derive(PartialEq, Eq)]
648 struct IrrevocablyResolvedHTLC {
649         commitment_tx_output_idx: Option<u32>,
650         /// The txid of the transaction which resolved the HTLC, this may be a commitment (if the HTLC
651         /// was not present in the confirmed commitment transaction), HTLC-Success, or HTLC-Timeout
652         /// transaction.
653         resolving_txid: Option<Txid>, // Added as optional, but always filled in, in 0.0.110
654         resolving_tx: Option<Transaction>,
655         /// Only set if the HTLC claim was ours using a payment preimage
656         payment_preimage: Option<PaymentPreimage>,
657 }
658
659 // In LDK versions prior to 0.0.111 commitment_tx_output_idx was not Option-al and
660 // IrrevocablyResolvedHTLC objects only existed for non-dust HTLCs. This was a bug, but to maintain
661 // backwards compatibility we must ensure we always write out a commitment_tx_output_idx field,
662 // using `u32::max_value()` as a sentinal to indicate the HTLC was dust.
663 impl Writeable for IrrevocablyResolvedHTLC {
664         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
665                 let mapped_commitment_tx_output_idx = self.commitment_tx_output_idx.unwrap_or(u32::max_value());
666                 write_tlv_fields!(writer, {
667                         (0, mapped_commitment_tx_output_idx, required),
668                         (1, self.resolving_txid, option),
669                         (2, self.payment_preimage, option),
670                         (3, self.resolving_tx, option),
671                 });
672                 Ok(())
673         }
674 }
675
676 impl Readable for IrrevocablyResolvedHTLC {
677         fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
678                 let mut mapped_commitment_tx_output_idx = 0;
679                 let mut resolving_txid = None;
680                 let mut payment_preimage = None;
681                 let mut resolving_tx = None;
682                 read_tlv_fields!(reader, {
683                         (0, mapped_commitment_tx_output_idx, required),
684                         (1, resolving_txid, option),
685                         (2, payment_preimage, option),
686                         (3, resolving_tx, option),
687                 });
688                 Ok(Self {
689                         commitment_tx_output_idx: if mapped_commitment_tx_output_idx == u32::max_value() { None } else { Some(mapped_commitment_tx_output_idx) },
690                         resolving_txid,
691                         payment_preimage,
692                         resolving_tx,
693                 })
694         }
695 }
696
697 /// A ChannelMonitor handles chain events (blocks connected and disconnected) and generates
698 /// on-chain transactions to ensure no loss of funds occurs.
699 ///
700 /// You MUST ensure that no ChannelMonitors for a given channel anywhere contain out-of-date
701 /// information and are actively monitoring the chain.
702 ///
703 /// Pending Events or updated HTLCs which have not yet been read out by
704 /// get_and_clear_pending_monitor_events or get_and_clear_pending_events are serialized to disk and
705 /// reloaded at deserialize-time. Thus, you must ensure that, when handling events, all events
706 /// gotten are fully handled before re-serializing the new state.
707 ///
708 /// Note that the deserializer is only implemented for (BlockHash, ChannelMonitor), which
709 /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
710 /// the "reorg path" (ie disconnecting blocks until you find a common ancestor from both the
711 /// returned block hash and the the current chain and then reconnecting blocks to get to the
712 /// best chain) upon deserializing the object!
713 pub struct ChannelMonitor<Signer: WriteableEcdsaChannelSigner> {
714         #[cfg(test)]
715         pub(crate) inner: Mutex<ChannelMonitorImpl<Signer>>,
716         #[cfg(not(test))]
717         inner: Mutex<ChannelMonitorImpl<Signer>>,
718 }
719
720 #[derive(PartialEq)]
721 pub(crate) struct ChannelMonitorImpl<Signer: WriteableEcdsaChannelSigner> {
722         latest_update_id: u64,
723         commitment_transaction_number_obscure_factor: u64,
724
725         destination_script: Script,
726         broadcasted_holder_revokable_script: Option<(Script, PublicKey, PublicKey)>,
727         counterparty_payment_script: Script,
728         shutdown_script: Option<Script>,
729
730         channel_keys_id: [u8; 32],
731         holder_revocation_basepoint: PublicKey,
732         funding_info: (OutPoint, Script),
733         current_counterparty_commitment_txid: Option<Txid>,
734         prev_counterparty_commitment_txid: Option<Txid>,
735
736         counterparty_commitment_params: CounterpartyCommitmentParameters,
737         funding_redeemscript: Script,
738         channel_value_satoshis: u64,
739         // first is the idx of the first of the two per-commitment points
740         their_cur_per_commitment_points: Option<(u64, PublicKey, Option<PublicKey>)>,
741
742         on_holder_tx_csv: u16,
743
744         commitment_secrets: CounterpartyCommitmentSecrets,
745         /// The set of outpoints in each counterparty commitment transaction. We always need at least
746         /// the payment hash from `HTLCOutputInCommitment` to claim even a revoked commitment
747         /// transaction broadcast as we need to be able to construct the witness script in all cases.
748         counterparty_claimable_outpoints: HashMap<Txid, Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>>,
749         /// We cannot identify HTLC-Success or HTLC-Timeout transactions by themselves on the chain.
750         /// Nor can we figure out their commitment numbers without the commitment transaction they are
751         /// spending. Thus, in order to claim them via revocation key, we track all the counterparty
752         /// commitment transactions which we find on-chain, mapping them to the commitment number which
753         /// can be used to derive the revocation key and claim the transactions.
754         counterparty_commitment_txn_on_chain: HashMap<Txid, u64>,
755         /// Cache used to make pruning of payment_preimages faster.
756         /// Maps payment_hash values to commitment numbers for counterparty transactions for non-revoked
757         /// counterparty transactions (ie should remain pretty small).
758         /// Serialized to disk but should generally not be sent to Watchtowers.
759         counterparty_hash_commitment_number: HashMap<PaymentHash, u64>,
760
761         counterparty_fulfilled_htlcs: HashMap<SentHTLCId, PaymentPreimage>,
762
763         // We store two holder commitment transactions to avoid any race conditions where we may update
764         // some monitors (potentially on watchtowers) but then fail to update others, resulting in the
765         // various monitors for one channel being out of sync, and us broadcasting a holder
766         // transaction for which we have deleted claim information on some watchtowers.
767         prev_holder_signed_commitment_tx: Option<HolderSignedTx>,
768         current_holder_commitment_tx: HolderSignedTx,
769
770         // Used just for ChannelManager to make sure it has the latest channel data during
771         // deserialization
772         current_counterparty_commitment_number: u64,
773         // Used just for ChannelManager to make sure it has the latest channel data during
774         // deserialization
775         current_holder_commitment_number: u64,
776
777         /// The set of payment hashes from inbound payments for which we know the preimage. Payment
778         /// preimages that are not included in any unrevoked local commitment transaction or unrevoked
779         /// remote commitment transactions are automatically removed when commitment transactions are
780         /// revoked.
781         payment_preimages: HashMap<PaymentHash, PaymentPreimage>,
782
783         // Note that `MonitorEvent`s MUST NOT be generated during update processing, only generated
784         // during chain data processing. This prevents a race in `ChainMonitor::update_channel` (and
785         // presumably user implementations thereof as well) where we update the in-memory channel
786         // object, then before the persistence finishes (as it's all under a read-lock), we return
787         // pending events to the user or to the relevant `ChannelManager`. Then, on reload, we'll have
788         // the pre-event state here, but have processed the event in the `ChannelManager`.
789         // Note that because the `event_lock` in `ChainMonitor` is only taken in
790         // block/transaction-connected events and *not* during block/transaction-disconnected events,
791         // we further MUST NOT generate events during block/transaction-disconnection.
792         pending_monitor_events: Vec<MonitorEvent>,
793
794         pending_events: Vec<Event>,
795
796         // Used to track on-chain events (i.e., transactions part of channels confirmed on chain) on
797         // which to take actions once they reach enough confirmations. Each entry includes the
798         // transaction's id and the height when the transaction was confirmed on chain.
799         onchain_events_awaiting_threshold_conf: Vec<OnchainEventEntry>,
800
801         // If we get serialized out and re-read, we need to make sure that the chain monitoring
802         // interface knows about the TXOs that we want to be notified of spends of. We could probably
803         // be smart and derive them from the above storage fields, but its much simpler and more
804         // Obviously Correct (tm) if we just keep track of them explicitly.
805         outputs_to_watch: HashMap<Txid, Vec<(u32, Script)>>,
806
807         #[cfg(test)]
808         pub onchain_tx_handler: OnchainTxHandler<Signer>,
809         #[cfg(not(test))]
810         onchain_tx_handler: OnchainTxHandler<Signer>,
811
812         // This is set when the Channel[Manager] generated a ChannelMonitorUpdate which indicated the
813         // channel has been force-closed. After this is set, no further holder commitment transaction
814         // updates may occur, and we panic!() if one is provided.
815         lockdown_from_offchain: bool,
816
817         // Set once we've signed a holder commitment transaction and handed it over to our
818         // OnchainTxHandler. After this is set, no future updates to our holder commitment transactions
819         // may occur, and we fail any such monitor updates.
820         //
821         // In case of update rejection due to a locally already signed commitment transaction, we
822         // nevertheless store update content to track in case of concurrent broadcast by another
823         // remote monitor out-of-order with regards to the block view.
824         holder_tx_signed: bool,
825
826         // If a spend of the funding output is seen, we set this to true and reject any further
827         // updates. This prevents any further changes in the offchain state no matter the order
828         // of block connection between ChannelMonitors and the ChannelManager.
829         funding_spend_seen: bool,
830
831         /// Set to `Some` of the confirmed transaction spending the funding input of the channel after
832         /// reaching `ANTI_REORG_DELAY` confirmations.
833         funding_spend_confirmed: Option<Txid>,
834
835         confirmed_commitment_tx_counterparty_output: CommitmentTxCounterpartyOutputInfo,
836         /// The set of HTLCs which have been either claimed or failed on chain and have reached
837         /// the requisite confirmations on the claim/fail transaction (either ANTI_REORG_DELAY or the
838         /// spending CSV for revocable outputs).
839         htlcs_resolved_on_chain: Vec<IrrevocablyResolvedHTLC>,
840
841         /// The set of `SpendableOutput` events which we have already passed upstream to be claimed.
842         /// These are tracked explicitly to ensure that we don't generate the same events redundantly
843         /// if users duplicatively confirm old transactions. Specifically for transactions claiming a
844         /// revoked remote outpoint we otherwise have no tracking at all once they've reached
845         /// [`ANTI_REORG_DELAY`], so we have to track them here.
846         spendable_txids_confirmed: Vec<Txid>,
847
848         // We simply modify best_block in Channel's block_connected so that serialization is
849         // consistent but hopefully the users' copy handles block_connected in a consistent way.
850         // (we do *not*, however, update them in update_monitor to ensure any local user copies keep
851         // their best_block from its state and not based on updated copies that didn't run through
852         // the full block_connected).
853         best_block: BestBlock,
854
855         /// The node_id of our counterparty
856         counterparty_node_id: Option<PublicKey>,
857 }
858
859 /// Transaction outputs to watch for on-chain spends.
860 pub type TransactionOutputs = (Txid, Vec<(u32, TxOut)>);
861
862 impl<Signer: WriteableEcdsaChannelSigner> PartialEq for ChannelMonitor<Signer> where Signer: PartialEq {
863         fn eq(&self, other: &Self) -> bool {
864                 // We need some kind of total lockorder. Absent a better idea, we sort by position in
865                 // memory and take locks in that order (assuming that we can't move within memory while a
866                 // lock is held).
867                 let ord = ((self as *const _) as usize) < ((other as *const _) as usize);
868                 let a = if ord { self.inner.unsafe_well_ordered_double_lock_self() } else { other.inner.unsafe_well_ordered_double_lock_self() };
869                 let b = if ord { other.inner.unsafe_well_ordered_double_lock_self() } else { self.inner.unsafe_well_ordered_double_lock_self() };
870                 a.eq(&b)
871         }
872 }
873
874 impl<Signer: WriteableEcdsaChannelSigner> Writeable for ChannelMonitor<Signer> {
875         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), Error> {
876                 self.inner.lock().unwrap().write(writer)
877         }
878 }
879
880 // These are also used for ChannelMonitorUpdate, above.
881 const SERIALIZATION_VERSION: u8 = 1;
882 const MIN_SERIALIZATION_VERSION: u8 = 1;
883
884 impl<Signer: WriteableEcdsaChannelSigner> Writeable for ChannelMonitorImpl<Signer> {
885         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), Error> {
886                 write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
887
888                 self.latest_update_id.write(writer)?;
889
890                 // Set in initial Channel-object creation, so should always be set by now:
891                 U48(self.commitment_transaction_number_obscure_factor).write(writer)?;
892
893                 self.destination_script.write(writer)?;
894                 if let Some(ref broadcasted_holder_revokable_script) = self.broadcasted_holder_revokable_script {
895                         writer.write_all(&[0; 1])?;
896                         broadcasted_holder_revokable_script.0.write(writer)?;
897                         broadcasted_holder_revokable_script.1.write(writer)?;
898                         broadcasted_holder_revokable_script.2.write(writer)?;
899                 } else {
900                         writer.write_all(&[1; 1])?;
901                 }
902
903                 self.counterparty_payment_script.write(writer)?;
904                 match &self.shutdown_script {
905                         Some(script) => script.write(writer)?,
906                         None => Script::new().write(writer)?,
907                 }
908
909                 self.channel_keys_id.write(writer)?;
910                 self.holder_revocation_basepoint.write(writer)?;
911                 writer.write_all(&self.funding_info.0.txid[..])?;
912                 writer.write_all(&self.funding_info.0.index.to_be_bytes())?;
913                 self.funding_info.1.write(writer)?;
914                 self.current_counterparty_commitment_txid.write(writer)?;
915                 self.prev_counterparty_commitment_txid.write(writer)?;
916
917                 self.counterparty_commitment_params.write(writer)?;
918                 self.funding_redeemscript.write(writer)?;
919                 self.channel_value_satoshis.write(writer)?;
920
921                 match self.their_cur_per_commitment_points {
922                         Some((idx, pubkey, second_option)) => {
923                                 writer.write_all(&byte_utils::be48_to_array(idx))?;
924                                 writer.write_all(&pubkey.serialize())?;
925                                 match second_option {
926                                         Some(second_pubkey) => {
927                                                 writer.write_all(&second_pubkey.serialize())?;
928                                         },
929                                         None => {
930                                                 writer.write_all(&[0; 33])?;
931                                         },
932                                 }
933                         },
934                         None => {
935                                 writer.write_all(&byte_utils::be48_to_array(0))?;
936                         },
937                 }
938
939                 writer.write_all(&self.on_holder_tx_csv.to_be_bytes())?;
940
941                 self.commitment_secrets.write(writer)?;
942
943                 macro_rules! serialize_htlc_in_commitment {
944                         ($htlc_output: expr) => {
945                                 writer.write_all(&[$htlc_output.offered as u8; 1])?;
946                                 writer.write_all(&$htlc_output.amount_msat.to_be_bytes())?;
947                                 writer.write_all(&$htlc_output.cltv_expiry.to_be_bytes())?;
948                                 writer.write_all(&$htlc_output.payment_hash.0[..])?;
949                                 $htlc_output.transaction_output_index.write(writer)?;
950                         }
951                 }
952
953                 writer.write_all(&(self.counterparty_claimable_outpoints.len() as u64).to_be_bytes())?;
954                 for (ref txid, ref htlc_infos) in self.counterparty_claimable_outpoints.iter() {
955                         writer.write_all(&txid[..])?;
956                         writer.write_all(&(htlc_infos.len() as u64).to_be_bytes())?;
957                         for &(ref htlc_output, ref htlc_source) in htlc_infos.iter() {
958                                 debug_assert!(htlc_source.is_none() || Some(**txid) == self.current_counterparty_commitment_txid
959                                                 || Some(**txid) == self.prev_counterparty_commitment_txid,
960                                         "HTLC Sources for all revoked commitment transactions should be none!");
961                                 serialize_htlc_in_commitment!(htlc_output);
962                                 htlc_source.as_ref().map(|b| b.as_ref()).write(writer)?;
963                         }
964                 }
965
966                 writer.write_all(&(self.counterparty_commitment_txn_on_chain.len() as u64).to_be_bytes())?;
967                 for (ref txid, commitment_number) in self.counterparty_commitment_txn_on_chain.iter() {
968                         writer.write_all(&txid[..])?;
969                         writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
970                 }
971
972                 writer.write_all(&(self.counterparty_hash_commitment_number.len() as u64).to_be_bytes())?;
973                 for (ref payment_hash, commitment_number) in self.counterparty_hash_commitment_number.iter() {
974                         writer.write_all(&payment_hash.0[..])?;
975                         writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
976                 }
977
978                 if let Some(ref prev_holder_tx) = self.prev_holder_signed_commitment_tx {
979                         writer.write_all(&[1; 1])?;
980                         prev_holder_tx.write(writer)?;
981                 } else {
982                         writer.write_all(&[0; 1])?;
983                 }
984
985                 self.current_holder_commitment_tx.write(writer)?;
986
987                 writer.write_all(&byte_utils::be48_to_array(self.current_counterparty_commitment_number))?;
988                 writer.write_all(&byte_utils::be48_to_array(self.current_holder_commitment_number))?;
989
990                 writer.write_all(&(self.payment_preimages.len() as u64).to_be_bytes())?;
991                 for payment_preimage in self.payment_preimages.values() {
992                         writer.write_all(&payment_preimage.0[..])?;
993                 }
994
995                 writer.write_all(&(self.pending_monitor_events.iter().filter(|ev| match ev {
996                         MonitorEvent::HTLCEvent(_) => true,
997                         MonitorEvent::CommitmentTxConfirmed(_) => true,
998                         _ => false,
999                 }).count() as u64).to_be_bytes())?;
1000                 for event in self.pending_monitor_events.iter() {
1001                         match event {
1002                                 MonitorEvent::HTLCEvent(upd) => {
1003                                         0u8.write(writer)?;
1004                                         upd.write(writer)?;
1005                                 },
1006                                 MonitorEvent::CommitmentTxConfirmed(_) => 1u8.write(writer)?,
1007                                 _ => {}, // Covered in the TLV writes below
1008                         }
1009                 }
1010
1011                 writer.write_all(&(self.pending_events.len() as u64).to_be_bytes())?;
1012                 for event in self.pending_events.iter() {
1013                         event.write(writer)?;
1014                 }
1015
1016                 self.best_block.block_hash().write(writer)?;
1017                 writer.write_all(&self.best_block.height().to_be_bytes())?;
1018
1019                 writer.write_all(&(self.onchain_events_awaiting_threshold_conf.len() as u64).to_be_bytes())?;
1020                 for ref entry in self.onchain_events_awaiting_threshold_conf.iter() {
1021                         entry.write(writer)?;
1022                 }
1023
1024                 (self.outputs_to_watch.len() as u64).write(writer)?;
1025                 for (txid, idx_scripts) in self.outputs_to_watch.iter() {
1026                         txid.write(writer)?;
1027                         (idx_scripts.len() as u64).write(writer)?;
1028                         for (idx, script) in idx_scripts.iter() {
1029                                 idx.write(writer)?;
1030                                 script.write(writer)?;
1031                         }
1032                 }
1033                 self.onchain_tx_handler.write(writer)?;
1034
1035                 self.lockdown_from_offchain.write(writer)?;
1036                 self.holder_tx_signed.write(writer)?;
1037
1038                 write_tlv_fields!(writer, {
1039                         (1, self.funding_spend_confirmed, option),
1040                         (3, self.htlcs_resolved_on_chain, vec_type),
1041                         (5, self.pending_monitor_events, vec_type),
1042                         (7, self.funding_spend_seen, required),
1043                         (9, self.counterparty_node_id, option),
1044                         (11, self.confirmed_commitment_tx_counterparty_output, option),
1045                         (13, self.spendable_txids_confirmed, vec_type),
1046                         (15, self.counterparty_fulfilled_htlcs, required),
1047                 });
1048
1049                 Ok(())
1050         }
1051 }
1052
1053 impl<Signer: WriteableEcdsaChannelSigner> ChannelMonitor<Signer> {
1054         /// For lockorder enforcement purposes, we need to have a single site which constructs the
1055         /// `inner` mutex, otherwise cases where we lock two monitors at the same time (eg in our
1056         /// PartialEq implementation) we may decide a lockorder violation has occurred.
1057         fn from_impl(imp: ChannelMonitorImpl<Signer>) -> Self {
1058                 ChannelMonitor { inner: Mutex::new(imp) }
1059         }
1060
1061         pub(crate) fn new(secp_ctx: Secp256k1<secp256k1::All>, keys: Signer, shutdown_script: Option<Script>,
1062                           on_counterparty_tx_csv: u16, destination_script: &Script, funding_info: (OutPoint, Script),
1063                           channel_parameters: &ChannelTransactionParameters,
1064                           funding_redeemscript: Script, channel_value_satoshis: u64,
1065                           commitment_transaction_number_obscure_factor: u64,
1066                           initial_holder_commitment_tx: HolderCommitmentTransaction,
1067                           best_block: BestBlock, counterparty_node_id: PublicKey) -> ChannelMonitor<Signer> {
1068
1069                 assert!(commitment_transaction_number_obscure_factor <= (1 << 48));
1070                 let payment_key_hash = WPubkeyHash::hash(&keys.pubkeys().payment_point.serialize());
1071                 let counterparty_payment_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&payment_key_hash[..]).into_script();
1072
1073                 let counterparty_channel_parameters = channel_parameters.counterparty_parameters.as_ref().unwrap();
1074                 let counterparty_delayed_payment_base_key = counterparty_channel_parameters.pubkeys.delayed_payment_basepoint;
1075                 let counterparty_htlc_base_key = counterparty_channel_parameters.pubkeys.htlc_basepoint;
1076                 let counterparty_commitment_params = CounterpartyCommitmentParameters { counterparty_delayed_payment_base_key, counterparty_htlc_base_key, on_counterparty_tx_csv };
1077
1078                 let channel_keys_id = keys.channel_keys_id();
1079                 let holder_revocation_basepoint = keys.pubkeys().revocation_basepoint;
1080
1081                 // block for Rust 1.34 compat
1082                 let (holder_commitment_tx, current_holder_commitment_number) = {
1083                         let trusted_tx = initial_holder_commitment_tx.trust();
1084                         let txid = trusted_tx.txid();
1085
1086                         let tx_keys = trusted_tx.keys();
1087                         let holder_commitment_tx = HolderSignedTx {
1088                                 txid,
1089                                 revocation_key: tx_keys.revocation_key,
1090                                 a_htlc_key: tx_keys.broadcaster_htlc_key,
1091                                 b_htlc_key: tx_keys.countersignatory_htlc_key,
1092                                 delayed_payment_key: tx_keys.broadcaster_delayed_payment_key,
1093                                 per_commitment_point: tx_keys.per_commitment_point,
1094                                 htlc_outputs: Vec::new(), // There are never any HTLCs in the initial commitment transactions
1095                                 to_self_value_sat: initial_holder_commitment_tx.to_broadcaster_value_sat(),
1096                                 feerate_per_kw: trusted_tx.feerate_per_kw(),
1097                         };
1098                         (holder_commitment_tx, trusted_tx.commitment_number())
1099                 };
1100
1101                 let onchain_tx_handler =
1102                         OnchainTxHandler::new(destination_script.clone(), keys,
1103                         channel_parameters.clone(), initial_holder_commitment_tx, secp_ctx);
1104
1105                 let mut outputs_to_watch = HashMap::new();
1106                 outputs_to_watch.insert(funding_info.0.txid, vec![(funding_info.0.index as u32, funding_info.1.clone())]);
1107
1108                 Self::from_impl(ChannelMonitorImpl {
1109                         latest_update_id: 0,
1110                         commitment_transaction_number_obscure_factor,
1111
1112                         destination_script: destination_script.clone(),
1113                         broadcasted_holder_revokable_script: None,
1114                         counterparty_payment_script,
1115                         shutdown_script,
1116
1117                         channel_keys_id,
1118                         holder_revocation_basepoint,
1119                         funding_info,
1120                         current_counterparty_commitment_txid: None,
1121                         prev_counterparty_commitment_txid: None,
1122
1123                         counterparty_commitment_params,
1124                         funding_redeemscript,
1125                         channel_value_satoshis,
1126                         their_cur_per_commitment_points: None,
1127
1128                         on_holder_tx_csv: counterparty_channel_parameters.selected_contest_delay,
1129
1130                         commitment_secrets: CounterpartyCommitmentSecrets::new(),
1131                         counterparty_claimable_outpoints: HashMap::new(),
1132                         counterparty_commitment_txn_on_chain: HashMap::new(),
1133                         counterparty_hash_commitment_number: HashMap::new(),
1134                         counterparty_fulfilled_htlcs: HashMap::new(),
1135
1136                         prev_holder_signed_commitment_tx: None,
1137                         current_holder_commitment_tx: holder_commitment_tx,
1138                         current_counterparty_commitment_number: 1 << 48,
1139                         current_holder_commitment_number,
1140
1141                         payment_preimages: HashMap::new(),
1142                         pending_monitor_events: Vec::new(),
1143                         pending_events: Vec::new(),
1144
1145                         onchain_events_awaiting_threshold_conf: Vec::new(),
1146                         outputs_to_watch,
1147
1148                         onchain_tx_handler,
1149
1150                         lockdown_from_offchain: false,
1151                         holder_tx_signed: false,
1152                         funding_spend_seen: false,
1153                         funding_spend_confirmed: None,
1154                         confirmed_commitment_tx_counterparty_output: None,
1155                         htlcs_resolved_on_chain: Vec::new(),
1156                         spendable_txids_confirmed: Vec::new(),
1157
1158                         best_block,
1159                         counterparty_node_id: Some(counterparty_node_id),
1160                 })
1161         }
1162
1163         #[cfg(test)]
1164         fn provide_secret(&self, idx: u64, secret: [u8; 32]) -> Result<(), &'static str> {
1165                 self.inner.lock().unwrap().provide_secret(idx, secret)
1166         }
1167
1168         /// Informs this monitor of the latest counterparty (ie non-broadcastable) commitment transaction.
1169         /// The monitor watches for it to be broadcasted and then uses the HTLC information (and
1170         /// possibly future revocation/preimage information) to claim outputs where possible.
1171         /// We cache also the mapping hash:commitment number to lighten pruning of old preimages by watchtowers.
1172         pub(crate) fn provide_latest_counterparty_commitment_tx<L: Deref>(
1173                 &self,
1174                 txid: Txid,
1175                 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
1176                 commitment_number: u64,
1177                 their_per_commitment_point: PublicKey,
1178                 logger: &L,
1179         ) where L::Target: Logger {
1180                 self.inner.lock().unwrap().provide_latest_counterparty_commitment_tx(
1181                         txid, htlc_outputs, commitment_number, their_per_commitment_point, logger)
1182         }
1183
1184         #[cfg(test)]
1185         fn provide_latest_holder_commitment_tx(
1186                 &self, holder_commitment_tx: HolderCommitmentTransaction,
1187                 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
1188         ) -> Result<(), ()> {
1189                 self.inner.lock().unwrap().provide_latest_holder_commitment_tx(holder_commitment_tx, htlc_outputs, &Vec::new(), Vec::new()).map_err(|_| ())
1190         }
1191
1192         /// This is used to provide payment preimage(s) out-of-band during startup without updating the
1193         /// off-chain state with a new commitment transaction.
1194         pub(crate) fn provide_payment_preimage<B: Deref, F: Deref, L: Deref>(
1195                 &self,
1196                 payment_hash: &PaymentHash,
1197                 payment_preimage: &PaymentPreimage,
1198                 broadcaster: &B,
1199                 fee_estimator: &LowerBoundedFeeEstimator<F>,
1200                 logger: &L,
1201         ) where
1202                 B::Target: BroadcasterInterface,
1203                 F::Target: FeeEstimator,
1204                 L::Target: Logger,
1205         {
1206                 self.inner.lock().unwrap().provide_payment_preimage(
1207                         payment_hash, payment_preimage, broadcaster, fee_estimator, logger)
1208         }
1209
1210         /// Updates a ChannelMonitor on the basis of some new information provided by the Channel
1211         /// itself.
1212         ///
1213         /// panics if the given update is not the next update by update_id.
1214         pub fn update_monitor<B: Deref, F: Deref, L: Deref>(
1215                 &self,
1216                 updates: &ChannelMonitorUpdate,
1217                 broadcaster: &B,
1218                 fee_estimator: F,
1219                 logger: &L,
1220         ) -> Result<(), ()>
1221         where
1222                 B::Target: BroadcasterInterface,
1223                 F::Target: FeeEstimator,
1224                 L::Target: Logger,
1225         {
1226                 self.inner.lock().unwrap().update_monitor(updates, broadcaster, fee_estimator, logger)
1227         }
1228
1229         /// Gets the update_id from the latest ChannelMonitorUpdate which was applied to this
1230         /// ChannelMonitor.
1231         pub fn get_latest_update_id(&self) -> u64 {
1232                 self.inner.lock().unwrap().get_latest_update_id()
1233         }
1234
1235         /// Gets the funding transaction outpoint of the channel this ChannelMonitor is monitoring for.
1236         pub fn get_funding_txo(&self) -> (OutPoint, Script) {
1237                 self.inner.lock().unwrap().get_funding_txo().clone()
1238         }
1239
1240         /// Gets a list of txids, with their output scripts (in the order they appear in the
1241         /// transaction), which we must learn about spends of via block_connected().
1242         pub fn get_outputs_to_watch(&self) -> Vec<(Txid, Vec<(u32, Script)>)> {
1243                 self.inner.lock().unwrap().get_outputs_to_watch()
1244                         .iter().map(|(txid, outputs)| (*txid, outputs.clone())).collect()
1245         }
1246
1247         /// Loads the funding txo and outputs to watch into the given `chain::Filter` by repeatedly
1248         /// calling `chain::Filter::register_output` and `chain::Filter::register_tx` until all outputs
1249         /// have been registered.
1250         pub fn load_outputs_to_watch<F: Deref>(&self, filter: &F) where F::Target: chain::Filter {
1251                 let lock = self.inner.lock().unwrap();
1252                 filter.register_tx(&lock.get_funding_txo().0.txid, &lock.get_funding_txo().1);
1253                 for (txid, outputs) in lock.get_outputs_to_watch().iter() {
1254                         for (index, script_pubkey) in outputs.iter() {
1255                                 assert!(*index <= u16::max_value() as u32);
1256                                 filter.register_output(WatchedOutput {
1257                                         block_hash: None,
1258                                         outpoint: OutPoint { txid: *txid, index: *index as u16 },
1259                                         script_pubkey: script_pubkey.clone(),
1260                                 });
1261                         }
1262                 }
1263         }
1264
1265         /// Get the list of HTLCs who's status has been updated on chain. This should be called by
1266         /// ChannelManager via [`chain::Watch::release_pending_monitor_events`].
1267         pub fn get_and_clear_pending_monitor_events(&self) -> Vec<MonitorEvent> {
1268                 self.inner.lock().unwrap().get_and_clear_pending_monitor_events()
1269         }
1270
1271         /// Gets the list of pending events which were generated by previous actions, clearing the list
1272         /// in the process.
1273         ///
1274         /// This is called by the [`EventsProvider::process_pending_events`] implementation for
1275         /// [`ChainMonitor`].
1276         ///
1277         /// [`EventsProvider::process_pending_events`]: crate::events::EventsProvider::process_pending_events
1278         /// [`ChainMonitor`]: crate::chain::chainmonitor::ChainMonitor
1279         pub fn get_and_clear_pending_events(&self) -> Vec<Event> {
1280                 self.inner.lock().unwrap().get_and_clear_pending_events()
1281         }
1282
1283         pub(crate) fn get_min_seen_secret(&self) -> u64 {
1284                 self.inner.lock().unwrap().get_min_seen_secret()
1285         }
1286
1287         pub(crate) fn get_cur_counterparty_commitment_number(&self) -> u64 {
1288                 self.inner.lock().unwrap().get_cur_counterparty_commitment_number()
1289         }
1290
1291         pub(crate) fn get_cur_holder_commitment_number(&self) -> u64 {
1292                 self.inner.lock().unwrap().get_cur_holder_commitment_number()
1293         }
1294
1295         /// Gets the `node_id` of the counterparty for this channel.
1296         ///
1297         /// Will be `None` for channels constructed on LDK versions prior to 0.0.110 and always `Some`
1298         /// otherwise.
1299         pub fn get_counterparty_node_id(&self) -> Option<PublicKey> {
1300                 self.inner.lock().unwrap().counterparty_node_id
1301         }
1302
1303         /// Used by ChannelManager deserialization to broadcast the latest holder state if its copy of
1304         /// the Channel was out-of-date.
1305         ///
1306         /// You may also use this to broadcast the latest local commitment transaction, either because
1307         /// a monitor update failed with [`ChannelMonitorUpdateStatus::PermanentFailure`] or because we've
1308         /// fallen behind (i.e. we've received proof that our counterparty side knows a revocation
1309         /// secret we gave them that they shouldn't know).
1310         ///
1311         /// Broadcasting these transactions in the second case is UNSAFE, as they allow counterparty
1312         /// side to punish you. Nevertheless you may want to broadcast them if counterparty doesn't
1313         /// close channel with their commitment transaction after a substantial amount of time. Best
1314         /// may be to contact the other node operator out-of-band to coordinate other options available
1315         /// to you. In any-case, the choice is up to you.
1316         ///
1317         /// [`ChannelMonitorUpdateStatus::PermanentFailure`]: super::ChannelMonitorUpdateStatus::PermanentFailure
1318         pub fn get_latest_holder_commitment_txn<L: Deref>(&self, logger: &L) -> Vec<Transaction>
1319         where L::Target: Logger {
1320                 self.inner.lock().unwrap().get_latest_holder_commitment_txn(logger)
1321         }
1322
1323         /// Unsafe test-only version of get_latest_holder_commitment_txn used by our test framework
1324         /// to bypass HolderCommitmentTransaction state update lockdown after signature and generate
1325         /// revoked commitment transaction.
1326         #[cfg(any(test, feature = "unsafe_revoked_tx_signing"))]
1327         pub fn unsafe_get_latest_holder_commitment_txn<L: Deref>(&self, logger: &L) -> Vec<Transaction>
1328         where L::Target: Logger {
1329                 self.inner.lock().unwrap().unsafe_get_latest_holder_commitment_txn(logger)
1330         }
1331
1332         /// Processes transactions in a newly connected block, which may result in any of the following:
1333         /// - update the monitor's state against resolved HTLCs
1334         /// - punish the counterparty in the case of seeing a revoked commitment transaction
1335         /// - force close the channel and claim/timeout incoming/outgoing HTLCs if near expiration
1336         /// - detect settled outputs for later spending
1337         /// - schedule and bump any in-flight claims
1338         ///
1339         /// Returns any new outputs to watch from `txdata`; after called, these are also included in
1340         /// [`get_outputs_to_watch`].
1341         ///
1342         /// [`get_outputs_to_watch`]: #method.get_outputs_to_watch
1343         pub fn block_connected<B: Deref, F: Deref, L: Deref>(
1344                 &self,
1345                 header: &BlockHeader,
1346                 txdata: &TransactionData,
1347                 height: u32,
1348                 broadcaster: B,
1349                 fee_estimator: F,
1350                 logger: L,
1351         ) -> Vec<TransactionOutputs>
1352         where
1353                 B::Target: BroadcasterInterface,
1354                 F::Target: FeeEstimator,
1355                 L::Target: Logger,
1356         {
1357                 self.inner.lock().unwrap().block_connected(
1358                         header, txdata, height, broadcaster, fee_estimator, logger)
1359         }
1360
1361         /// Determines if the disconnected block contained any transactions of interest and updates
1362         /// appropriately.
1363         pub fn block_disconnected<B: Deref, F: Deref, L: Deref>(
1364                 &self,
1365                 header: &BlockHeader,
1366                 height: u32,
1367                 broadcaster: B,
1368                 fee_estimator: F,
1369                 logger: L,
1370         ) where
1371                 B::Target: BroadcasterInterface,
1372                 F::Target: FeeEstimator,
1373                 L::Target: Logger,
1374         {
1375                 self.inner.lock().unwrap().block_disconnected(
1376                         header, height, broadcaster, fee_estimator, logger)
1377         }
1378
1379         /// Processes transactions confirmed in a block with the given header and height, returning new
1380         /// outputs to watch. See [`block_connected`] for details.
1381         ///
1382         /// Used instead of [`block_connected`] by clients that are notified of transactions rather than
1383         /// blocks. See [`chain::Confirm`] for calling expectations.
1384         ///
1385         /// [`block_connected`]: Self::block_connected
1386         pub fn transactions_confirmed<B: Deref, F: Deref, L: Deref>(
1387                 &self,
1388                 header: &BlockHeader,
1389                 txdata: &TransactionData,
1390                 height: u32,
1391                 broadcaster: B,
1392                 fee_estimator: F,
1393                 logger: L,
1394         ) -> Vec<TransactionOutputs>
1395         where
1396                 B::Target: BroadcasterInterface,
1397                 F::Target: FeeEstimator,
1398                 L::Target: Logger,
1399         {
1400                 let bounded_fee_estimator = LowerBoundedFeeEstimator::new(fee_estimator);
1401                 self.inner.lock().unwrap().transactions_confirmed(
1402                         header, txdata, height, broadcaster, &bounded_fee_estimator, logger)
1403         }
1404
1405         /// Processes a transaction that was reorganized out of the chain.
1406         ///
1407         /// Used instead of [`block_disconnected`] by clients that are notified of transactions rather
1408         /// than blocks. See [`chain::Confirm`] for calling expectations.
1409         ///
1410         /// [`block_disconnected`]: Self::block_disconnected
1411         pub fn transaction_unconfirmed<B: Deref, F: Deref, L: Deref>(
1412                 &self,
1413                 txid: &Txid,
1414                 broadcaster: B,
1415                 fee_estimator: F,
1416                 logger: L,
1417         ) where
1418                 B::Target: BroadcasterInterface,
1419                 F::Target: FeeEstimator,
1420                 L::Target: Logger,
1421         {
1422                 let bounded_fee_estimator = LowerBoundedFeeEstimator::new(fee_estimator);
1423                 self.inner.lock().unwrap().transaction_unconfirmed(
1424                         txid, broadcaster, &bounded_fee_estimator, logger);
1425         }
1426
1427         /// Updates the monitor with the current best chain tip, returning new outputs to watch. See
1428         /// [`block_connected`] for details.
1429         ///
1430         /// Used instead of [`block_connected`] by clients that are notified of transactions rather than
1431         /// blocks. See [`chain::Confirm`] for calling expectations.
1432         ///
1433         /// [`block_connected`]: Self::block_connected
1434         pub fn best_block_updated<B: Deref, F: Deref, L: Deref>(
1435                 &self,
1436                 header: &BlockHeader,
1437                 height: u32,
1438                 broadcaster: B,
1439                 fee_estimator: F,
1440                 logger: L,
1441         ) -> Vec<TransactionOutputs>
1442         where
1443                 B::Target: BroadcasterInterface,
1444                 F::Target: FeeEstimator,
1445                 L::Target: Logger,
1446         {
1447                 let bounded_fee_estimator = LowerBoundedFeeEstimator::new(fee_estimator);
1448                 self.inner.lock().unwrap().best_block_updated(
1449                         header, height, broadcaster, &bounded_fee_estimator, logger)
1450         }
1451
1452         /// Returns the set of txids that should be monitored for re-organization out of the chain.
1453         pub fn get_relevant_txids(&self) -> Vec<(Txid, Option<BlockHash>)> {
1454                 let inner = self.inner.lock().unwrap();
1455                 let mut txids: Vec<(Txid, Option<BlockHash>)> = inner.onchain_events_awaiting_threshold_conf
1456                         .iter()
1457                         .map(|entry| (entry.txid, entry.block_hash))
1458                         .chain(inner.onchain_tx_handler.get_relevant_txids().into_iter())
1459                         .collect();
1460                 txids.sort_unstable();
1461                 txids.dedup();
1462                 txids
1463         }
1464
1465         /// Gets the latest best block which was connected either via the [`chain::Listen`] or
1466         /// [`chain::Confirm`] interfaces.
1467         pub fn current_best_block(&self) -> BestBlock {
1468                 self.inner.lock().unwrap().best_block.clone()
1469         }
1470 }
1471
1472 impl<Signer: WriteableEcdsaChannelSigner> ChannelMonitorImpl<Signer> {
1473         /// Helper for get_claimable_balances which does the work for an individual HTLC, generating up
1474         /// to one `Balance` for the HTLC.
1475         fn get_htlc_balance(&self, htlc: &HTLCOutputInCommitment, holder_commitment: bool,
1476                 counterparty_revoked_commitment: bool, confirmed_txid: Option<Txid>)
1477         -> Option<Balance> {
1478                 let htlc_commitment_tx_output_idx =
1479                         if let Some(v) = htlc.transaction_output_index { v } else { return None; };
1480
1481                 let mut htlc_spend_txid_opt = None;
1482                 let mut htlc_spend_tx_opt = None;
1483                 let mut holder_timeout_spend_pending = None;
1484                 let mut htlc_spend_pending = None;
1485                 let mut holder_delayed_output_pending = None;
1486                 for event in self.onchain_events_awaiting_threshold_conf.iter() {
1487                         match event.event {
1488                                 OnchainEvent::HTLCUpdate { commitment_tx_output_idx, htlc_value_satoshis, .. }
1489                                 if commitment_tx_output_idx == Some(htlc_commitment_tx_output_idx) => {
1490                                         debug_assert!(htlc_spend_txid_opt.is_none());
1491                                         htlc_spend_txid_opt = Some(&event.txid);
1492                                         debug_assert!(htlc_spend_tx_opt.is_none());
1493                                         htlc_spend_tx_opt = event.transaction.as_ref();
1494                                         debug_assert!(holder_timeout_spend_pending.is_none());
1495                                         debug_assert_eq!(htlc_value_satoshis.unwrap(), htlc.amount_msat / 1000);
1496                                         holder_timeout_spend_pending = Some(event.confirmation_threshold());
1497                                 },
1498                                 OnchainEvent::HTLCSpendConfirmation { commitment_tx_output_idx, preimage, .. }
1499                                 if commitment_tx_output_idx == htlc_commitment_tx_output_idx => {
1500                                         debug_assert!(htlc_spend_txid_opt.is_none());
1501                                         htlc_spend_txid_opt = Some(&event.txid);
1502                                         debug_assert!(htlc_spend_tx_opt.is_none());
1503                                         htlc_spend_tx_opt = event.transaction.as_ref();
1504                                         debug_assert!(htlc_spend_pending.is_none());
1505                                         htlc_spend_pending = Some((event.confirmation_threshold(), preimage.is_some()));
1506                                 },
1507                                 OnchainEvent::MaturingOutput {
1508                                         descriptor: SpendableOutputDescriptor::DelayedPaymentOutput(ref descriptor) }
1509                                 if descriptor.outpoint.index as u32 == htlc_commitment_tx_output_idx => {
1510                                         debug_assert!(holder_delayed_output_pending.is_none());
1511                                         holder_delayed_output_pending = Some(event.confirmation_threshold());
1512                                 },
1513                                 _ => {},
1514                         }
1515                 }
1516                 let htlc_resolved = self.htlcs_resolved_on_chain.iter()
1517                         .find(|v| if v.commitment_tx_output_idx == Some(htlc_commitment_tx_output_idx) {
1518                                 debug_assert!(htlc_spend_txid_opt.is_none());
1519                                 htlc_spend_txid_opt = v.resolving_txid.as_ref();
1520                                 debug_assert!(htlc_spend_tx_opt.is_none());
1521                                 htlc_spend_tx_opt = v.resolving_tx.as_ref();
1522                                 true
1523                         } else { false });
1524                 debug_assert!(holder_timeout_spend_pending.is_some() as u8 + htlc_spend_pending.is_some() as u8 + htlc_resolved.is_some() as u8 <= 1);
1525
1526                 let htlc_commitment_outpoint = BitcoinOutPoint::new(confirmed_txid.unwrap(), htlc_commitment_tx_output_idx);
1527                 let htlc_output_to_spend =
1528                         if let Some(txid) = htlc_spend_txid_opt {
1529                                 // Because HTLC transactions either only have 1 input and 1 output (pre-anchors) or
1530                                 // are signed with SIGHASH_SINGLE|ANYONECANPAY under BIP-0143 (post-anchors), we can
1531                                 // locate the correct output by ensuring its adjacent input spends the HTLC output
1532                                 // in the commitment.
1533                                 if let Some(ref tx) = htlc_spend_tx_opt {
1534                                         let htlc_input_idx_opt = tx.input.iter().enumerate()
1535                                                 .find(|(_, input)| input.previous_output == htlc_commitment_outpoint)
1536                                                 .map(|(idx, _)| idx as u32);
1537                                         debug_assert!(htlc_input_idx_opt.is_some());
1538                                         BitcoinOutPoint::new(*txid, htlc_input_idx_opt.unwrap_or(0))
1539                                 } else {
1540                                         debug_assert!(!self.onchain_tx_handler.opt_anchors());
1541                                         BitcoinOutPoint::new(*txid, 0)
1542                                 }
1543                         } else {
1544                                 htlc_commitment_outpoint
1545                         };
1546                 let htlc_output_spend_pending = self.onchain_tx_handler.is_output_spend_pending(&htlc_output_to_spend);
1547
1548                 if let Some(conf_thresh) = holder_delayed_output_pending {
1549                         debug_assert!(holder_commitment);
1550                         return Some(Balance::ClaimableAwaitingConfirmations {
1551                                 claimable_amount_satoshis: htlc.amount_msat / 1000,
1552                                 confirmation_height: conf_thresh,
1553                         });
1554                 } else if htlc_resolved.is_some() && !htlc_output_spend_pending {
1555                         // Funding transaction spends should be fully confirmed by the time any
1556                         // HTLC transactions are resolved, unless we're talking about a holder
1557                         // commitment tx, whose resolution is delayed until the CSV timeout is
1558                         // reached, even though HTLCs may be resolved after only
1559                         // ANTI_REORG_DELAY confirmations.
1560                         debug_assert!(holder_commitment || self.funding_spend_confirmed.is_some());
1561                 } else if counterparty_revoked_commitment {
1562                         let htlc_output_claim_pending = self.onchain_events_awaiting_threshold_conf.iter().find_map(|event| {
1563                                 if let OnchainEvent::MaturingOutput {
1564                                         descriptor: SpendableOutputDescriptor::StaticOutput { .. }
1565                                 } = &event.event {
1566                                         if event.transaction.as_ref().map(|tx| tx.input.iter().any(|inp| {
1567                                                 if let Some(htlc_spend_txid) = htlc_spend_txid_opt {
1568                                                         tx.txid() == *htlc_spend_txid || inp.previous_output.txid == *htlc_spend_txid
1569                                                 } else {
1570                                                         Some(inp.previous_output.txid) == confirmed_txid &&
1571                                                                 inp.previous_output.vout == htlc_commitment_tx_output_idx
1572                                                 }
1573                                         })).unwrap_or(false) {
1574                                                 Some(())
1575                                         } else { None }
1576                                 } else { None }
1577                         });
1578                         if htlc_output_claim_pending.is_some() {
1579                                 // We already push `Balance`s onto the `res` list for every
1580                                 // `StaticOutput` in a `MaturingOutput` in the revoked
1581                                 // counterparty commitment transaction case generally, so don't
1582                                 // need to do so again here.
1583                         } else {
1584                                 debug_assert!(holder_timeout_spend_pending.is_none(),
1585                                         "HTLCUpdate OnchainEvents should never appear for preimage claims");
1586                                 debug_assert!(!htlc.offered || htlc_spend_pending.is_none() || !htlc_spend_pending.unwrap().1,
1587                                         "We don't (currently) generate preimage claims against revoked outputs, where did you get one?!");
1588                                 return Some(Balance::CounterpartyRevokedOutputClaimable {
1589                                         claimable_amount_satoshis: htlc.amount_msat / 1000,
1590                                 });
1591                         }
1592                 } else if htlc.offered == holder_commitment {
1593                         // If the payment was outbound, check if there's an HTLCUpdate
1594                         // indicating we have spent this HTLC with a timeout, claiming it back
1595                         // and awaiting confirmations on it.
1596                         if let Some(conf_thresh) = holder_timeout_spend_pending {
1597                                 return Some(Balance::ClaimableAwaitingConfirmations {
1598                                         claimable_amount_satoshis: htlc.amount_msat / 1000,
1599                                         confirmation_height: conf_thresh,
1600                                 });
1601                         } else {
1602                                 return Some(Balance::MaybeTimeoutClaimableHTLC {
1603                                         claimable_amount_satoshis: htlc.amount_msat / 1000,
1604                                         claimable_height: htlc.cltv_expiry,
1605                                 });
1606                         }
1607                 } else if self.payment_preimages.get(&htlc.payment_hash).is_some() {
1608                         // Otherwise (the payment was inbound), only expose it as claimable if
1609                         // we know the preimage.
1610                         // Note that if there is a pending claim, but it did not use the
1611                         // preimage, we lost funds to our counterparty! We will then continue
1612                         // to show it as ContentiousClaimable until ANTI_REORG_DELAY.
1613                         debug_assert!(holder_timeout_spend_pending.is_none());
1614                         if let Some((conf_thresh, true)) = htlc_spend_pending {
1615                                 return Some(Balance::ClaimableAwaitingConfirmations {
1616                                         claimable_amount_satoshis: htlc.amount_msat / 1000,
1617                                         confirmation_height: conf_thresh,
1618                                 });
1619                         } else {
1620                                 return Some(Balance::ContentiousClaimable {
1621                                         claimable_amount_satoshis: htlc.amount_msat / 1000,
1622                                         timeout_height: htlc.cltv_expiry,
1623                                 });
1624                         }
1625                 } else if htlc_resolved.is_none() {
1626                         return Some(Balance::MaybePreimageClaimableHTLC {
1627                                 claimable_amount_satoshis: htlc.amount_msat / 1000,
1628                                 expiry_height: htlc.cltv_expiry,
1629                         });
1630                 }
1631                 None
1632         }
1633 }
1634
1635 impl<Signer: WriteableEcdsaChannelSigner> ChannelMonitor<Signer> {
1636         /// Gets the balances in this channel which are either claimable by us if we were to
1637         /// force-close the channel now or which are claimable on-chain (possibly awaiting
1638         /// confirmation).
1639         ///
1640         /// Any balances in the channel which are available on-chain (excluding on-chain fees) are
1641         /// included here until an [`Event::SpendableOutputs`] event has been generated for the
1642         /// balance, or until our counterparty has claimed the balance and accrued several
1643         /// confirmations on the claim transaction.
1644         ///
1645         /// Note that for `ChannelMonitors` which track a channel which went on-chain with versions of
1646         /// LDK prior to 0.0.111, balances may not be fully captured if our counterparty broadcasted
1647         /// a revoked state.
1648         ///
1649         /// See [`Balance`] for additional details on the types of claimable balances which
1650         /// may be returned here and their meanings.
1651         pub fn get_claimable_balances(&self) -> Vec<Balance> {
1652                 let mut res = Vec::new();
1653                 let us = self.inner.lock().unwrap();
1654
1655                 let mut confirmed_txid = us.funding_spend_confirmed;
1656                 let mut confirmed_counterparty_output = us.confirmed_commitment_tx_counterparty_output;
1657                 let mut pending_commitment_tx_conf_thresh = None;
1658                 let funding_spend_pending = us.onchain_events_awaiting_threshold_conf.iter().find_map(|event| {
1659                         if let OnchainEvent::FundingSpendConfirmation { commitment_tx_to_counterparty_output, .. } =
1660                                 event.event
1661                         {
1662                                 confirmed_counterparty_output = commitment_tx_to_counterparty_output;
1663                                 Some((event.txid, event.confirmation_threshold()))
1664                         } else { None }
1665                 });
1666                 if let Some((txid, conf_thresh)) = funding_spend_pending {
1667                         debug_assert!(us.funding_spend_confirmed.is_none(),
1668                                 "We have a pending funding spend awaiting anti-reorg confirmation, we can't have confirmed it already!");
1669                         confirmed_txid = Some(txid);
1670                         pending_commitment_tx_conf_thresh = Some(conf_thresh);
1671                 }
1672
1673                 macro_rules! walk_htlcs {
1674                         ($holder_commitment: expr, $counterparty_revoked_commitment: expr, $htlc_iter: expr) => {
1675                                 for htlc in $htlc_iter {
1676                                         if htlc.transaction_output_index.is_some() {
1677
1678                                                 if let Some(bal) = us.get_htlc_balance(htlc, $holder_commitment, $counterparty_revoked_commitment, confirmed_txid) {
1679                                                         res.push(bal);
1680                                                 }
1681                                         }
1682                                 }
1683                         }
1684                 }
1685
1686                 if let Some(txid) = confirmed_txid {
1687                         let mut found_commitment_tx = false;
1688                         if let Some(counterparty_tx_htlcs) = us.counterparty_claimable_outpoints.get(&txid) {
1689                                 // First look for the to_remote output back to us.
1690                                 if let Some(conf_thresh) = pending_commitment_tx_conf_thresh {
1691                                         if let Some(value) = us.onchain_events_awaiting_threshold_conf.iter().find_map(|event| {
1692                                                 if let OnchainEvent::MaturingOutput {
1693                                                         descriptor: SpendableOutputDescriptor::StaticPaymentOutput(descriptor)
1694                                                 } = &event.event {
1695                                                         Some(descriptor.output.value)
1696                                                 } else { None }
1697                                         }) {
1698                                                 res.push(Balance::ClaimableAwaitingConfirmations {
1699                                                         claimable_amount_satoshis: value,
1700                                                         confirmation_height: conf_thresh,
1701                                                 });
1702                                         } else {
1703                                                 // If a counterparty commitment transaction is awaiting confirmation, we
1704                                                 // should either have a StaticPaymentOutput MaturingOutput event awaiting
1705                                                 // confirmation with the same height or have never met our dust amount.
1706                                         }
1707                                 }
1708                                 if Some(txid) == us.current_counterparty_commitment_txid || Some(txid) == us.prev_counterparty_commitment_txid {
1709                                         walk_htlcs!(false, false, counterparty_tx_htlcs.iter().map(|(a, _)| a));
1710                                 } else {
1711                                         walk_htlcs!(false, true, counterparty_tx_htlcs.iter().map(|(a, _)| a));
1712                                         // The counterparty broadcasted a revoked state!
1713                                         // Look for any StaticOutputs first, generating claimable balances for those.
1714                                         // If any match the confirmed counterparty revoked to_self output, skip
1715                                         // generating a CounterpartyRevokedOutputClaimable.
1716                                         let mut spent_counterparty_output = false;
1717                                         for event in us.onchain_events_awaiting_threshold_conf.iter() {
1718                                                 if let OnchainEvent::MaturingOutput {
1719                                                         descriptor: SpendableOutputDescriptor::StaticOutput { output, .. }
1720                                                 } = &event.event {
1721                                                         res.push(Balance::ClaimableAwaitingConfirmations {
1722                                                                 claimable_amount_satoshis: output.value,
1723                                                                 confirmation_height: event.confirmation_threshold(),
1724                                                         });
1725                                                         if let Some(confirmed_to_self_idx) = confirmed_counterparty_output.map(|(idx, _)| idx) {
1726                                                                 if event.transaction.as_ref().map(|tx|
1727                                                                         tx.input.iter().any(|inp| inp.previous_output.vout == confirmed_to_self_idx)
1728                                                                 ).unwrap_or(false) {
1729                                                                         spent_counterparty_output = true;
1730                                                                 }
1731                                                         }
1732                                                 }
1733                                         }
1734
1735                                         if spent_counterparty_output {
1736                                         } else if let Some((confirmed_to_self_idx, amt)) = confirmed_counterparty_output {
1737                                                 let output_spendable = us.onchain_tx_handler
1738                                                         .is_output_spend_pending(&BitcoinOutPoint::new(txid, confirmed_to_self_idx));
1739                                                 if output_spendable {
1740                                                         res.push(Balance::CounterpartyRevokedOutputClaimable {
1741                                                                 claimable_amount_satoshis: amt,
1742                                                         });
1743                                                 }
1744                                         } else {
1745                                                 // Counterparty output is missing, either it was broadcasted on a
1746                                                 // previous version of LDK or the counterparty hadn't met dust.
1747                                         }
1748                                 }
1749                                 found_commitment_tx = true;
1750                         } else if txid == us.current_holder_commitment_tx.txid {
1751                                 walk_htlcs!(true, false, us.current_holder_commitment_tx.htlc_outputs.iter().map(|(a, _, _)| a));
1752                                 if let Some(conf_thresh) = pending_commitment_tx_conf_thresh {
1753                                         res.push(Balance::ClaimableAwaitingConfirmations {
1754                                                 claimable_amount_satoshis: us.current_holder_commitment_tx.to_self_value_sat,
1755                                                 confirmation_height: conf_thresh,
1756                                         });
1757                                 }
1758                                 found_commitment_tx = true;
1759                         } else if let Some(prev_commitment) = &us.prev_holder_signed_commitment_tx {
1760                                 if txid == prev_commitment.txid {
1761                                         walk_htlcs!(true, false, prev_commitment.htlc_outputs.iter().map(|(a, _, _)| a));
1762                                         if let Some(conf_thresh) = pending_commitment_tx_conf_thresh {
1763                                                 res.push(Balance::ClaimableAwaitingConfirmations {
1764                                                         claimable_amount_satoshis: prev_commitment.to_self_value_sat,
1765                                                         confirmation_height: conf_thresh,
1766                                                 });
1767                                         }
1768                                         found_commitment_tx = true;
1769                                 }
1770                         }
1771                         if !found_commitment_tx {
1772                                 if let Some(conf_thresh) = pending_commitment_tx_conf_thresh {
1773                                         // We blindly assume this is a cooperative close transaction here, and that
1774                                         // neither us nor our counterparty misbehaved. At worst we've under-estimated
1775                                         // the amount we can claim as we'll punish a misbehaving counterparty.
1776                                         res.push(Balance::ClaimableAwaitingConfirmations {
1777                                                 claimable_amount_satoshis: us.current_holder_commitment_tx.to_self_value_sat,
1778                                                 confirmation_height: conf_thresh,
1779                                         });
1780                                 }
1781                         }
1782                 } else {
1783                         let mut claimable_inbound_htlc_value_sat = 0;
1784                         for (htlc, _, _) in us.current_holder_commitment_tx.htlc_outputs.iter() {
1785                                 if htlc.transaction_output_index.is_none() { continue; }
1786                                 if htlc.offered {
1787                                         res.push(Balance::MaybeTimeoutClaimableHTLC {
1788                                                 claimable_amount_satoshis: htlc.amount_msat / 1000,
1789                                                 claimable_height: htlc.cltv_expiry,
1790                                         });
1791                                 } else if us.payment_preimages.get(&htlc.payment_hash).is_some() {
1792                                         claimable_inbound_htlc_value_sat += htlc.amount_msat / 1000;
1793                                 } else {
1794                                         // As long as the HTLC is still in our latest commitment state, treat
1795                                         // it as potentially claimable, even if it has long-since expired.
1796                                         res.push(Balance::MaybePreimageClaimableHTLC {
1797                                                 claimable_amount_satoshis: htlc.amount_msat / 1000,
1798                                                 expiry_height: htlc.cltv_expiry,
1799                                         });
1800                                 }
1801                         }
1802                         res.push(Balance::ClaimableOnChannelClose {
1803                                 claimable_amount_satoshis: us.current_holder_commitment_tx.to_self_value_sat + claimable_inbound_htlc_value_sat,
1804                         });
1805                 }
1806
1807                 res
1808         }
1809
1810         /// Gets the set of outbound HTLCs which can be (or have been) resolved by this
1811         /// `ChannelMonitor`. This is used to determine if an HTLC was removed from the channel prior
1812         /// to the `ChannelManager` having been persisted.
1813         ///
1814         /// This is similar to [`Self::get_pending_or_resolved_outbound_htlcs`] except it includes
1815         /// HTLCs which were resolved on-chain (i.e. where the final HTLC resolution was done by an
1816         /// event from this `ChannelMonitor`).
1817         pub(crate) fn get_all_current_outbound_htlcs(&self) -> HashMap<HTLCSource, (HTLCOutputInCommitment, Option<PaymentPreimage>)> {
1818                 let mut res = HashMap::new();
1819                 // Just examine the available counterparty commitment transactions. See docs on
1820                 // `fail_unbroadcast_htlcs`, below, for justification.
1821                 let us = self.inner.lock().unwrap();
1822                 macro_rules! walk_counterparty_commitment {
1823                         ($txid: expr) => {
1824                                 if let Some(ref latest_outpoints) = us.counterparty_claimable_outpoints.get($txid) {
1825                                         for &(ref htlc, ref source_option) in latest_outpoints.iter() {
1826                                                 if let &Some(ref source) = source_option {
1827                                                         res.insert((**source).clone(), (htlc.clone(),
1828                                                                 us.counterparty_fulfilled_htlcs.get(&SentHTLCId::from_source(source)).cloned()));
1829                                                 }
1830                                         }
1831                                 }
1832                         }
1833                 }
1834                 if let Some(ref txid) = us.current_counterparty_commitment_txid {
1835                         walk_counterparty_commitment!(txid);
1836                 }
1837                 if let Some(ref txid) = us.prev_counterparty_commitment_txid {
1838                         walk_counterparty_commitment!(txid);
1839                 }
1840                 res
1841         }
1842
1843         /// Gets the set of outbound HTLCs which are pending resolution in this channel or which were
1844         /// resolved with a preimage from our counterparty.
1845         ///
1846         /// This is used to reconstruct pending outbound payments on restart in the ChannelManager.
1847         ///
1848         /// Currently, the preimage is unused, however if it is present in the relevant internal state
1849         /// an HTLC is always included even if it has been resolved.
1850         pub(crate) fn get_pending_or_resolved_outbound_htlcs(&self) -> HashMap<HTLCSource, (HTLCOutputInCommitment, Option<PaymentPreimage>)> {
1851                 let us = self.inner.lock().unwrap();
1852                 // We're only concerned with the confirmation count of HTLC transactions, and don't
1853                 // actually care how many confirmations a commitment transaction may or may not have. Thus,
1854                 // we look for either a FundingSpendConfirmation event or a funding_spend_confirmed.
1855                 let confirmed_txid = us.funding_spend_confirmed.or_else(|| {
1856                         us.onchain_events_awaiting_threshold_conf.iter().find_map(|event| {
1857                                 if let OnchainEvent::FundingSpendConfirmation { .. } = event.event {
1858                                         Some(event.txid)
1859                                 } else { None }
1860                         })
1861                 });
1862
1863                 if confirmed_txid.is_none() {
1864                         // If we have not seen a commitment transaction on-chain (ie the channel is not yet
1865                         // closed), just get the full set.
1866                         mem::drop(us);
1867                         return self.get_all_current_outbound_htlcs();
1868                 }
1869
1870                 let mut res = HashMap::new();
1871                 macro_rules! walk_htlcs {
1872                         ($holder_commitment: expr, $htlc_iter: expr) => {
1873                                 for (htlc, source) in $htlc_iter {
1874                                         if us.htlcs_resolved_on_chain.iter().any(|v| v.commitment_tx_output_idx == htlc.transaction_output_index) {
1875                                                 // We should assert that funding_spend_confirmed is_some() here, but we
1876                                                 // have some unit tests which violate HTLC transaction CSVs entirely and
1877                                                 // would fail.
1878                                                 // TODO: Once tests all connect transactions at consensus-valid times, we
1879                                                 // should assert here like we do in `get_claimable_balances`.
1880                                         } else if htlc.offered == $holder_commitment {
1881                                                 // If the payment was outbound, check if there's an HTLCUpdate
1882                                                 // indicating we have spent this HTLC with a timeout, claiming it back
1883                                                 // and awaiting confirmations on it.
1884                                                 let htlc_update_confd = us.onchain_events_awaiting_threshold_conf.iter().any(|event| {
1885                                                         if let OnchainEvent::HTLCUpdate { commitment_tx_output_idx: Some(commitment_tx_output_idx), .. } = event.event {
1886                                                                 // If the HTLC was timed out, we wait for ANTI_REORG_DELAY blocks
1887                                                                 // before considering it "no longer pending" - this matches when we
1888                                                                 // provide the ChannelManager an HTLC failure event.
1889                                                                 Some(commitment_tx_output_idx) == htlc.transaction_output_index &&
1890                                                                         us.best_block.height() >= event.height + ANTI_REORG_DELAY - 1
1891                                                         } else if let OnchainEvent::HTLCSpendConfirmation { commitment_tx_output_idx, .. } = event.event {
1892                                                                 // If the HTLC was fulfilled with a preimage, we consider the HTLC
1893                                                                 // immediately non-pending, matching when we provide ChannelManager
1894                                                                 // the preimage.
1895                                                                 Some(commitment_tx_output_idx) == htlc.transaction_output_index
1896                                                         } else { false }
1897                                                 });
1898                                                 let counterparty_resolved_preimage_opt =
1899                                                         us.counterparty_fulfilled_htlcs.get(&SentHTLCId::from_source(source)).cloned();
1900                                                 if !htlc_update_confd || counterparty_resolved_preimage_opt.is_some() {
1901                                                         res.insert(source.clone(), (htlc.clone(), counterparty_resolved_preimage_opt));
1902                                                 }
1903                                         }
1904                                 }
1905                         }
1906                 }
1907
1908                 let txid = confirmed_txid.unwrap();
1909                 if Some(txid) == us.current_counterparty_commitment_txid || Some(txid) == us.prev_counterparty_commitment_txid {
1910                         walk_htlcs!(false, us.counterparty_claimable_outpoints.get(&txid).unwrap().iter().filter_map(|(a, b)| {
1911                                 if let &Some(ref source) = b {
1912                                         Some((a, &**source))
1913                                 } else { None }
1914                         }));
1915                 } else if txid == us.current_holder_commitment_tx.txid {
1916                         walk_htlcs!(true, us.current_holder_commitment_tx.htlc_outputs.iter().filter_map(|(a, _, c)| {
1917                                 if let Some(source) = c { Some((a, source)) } else { None }
1918                         }));
1919                 } else if let Some(prev_commitment) = &us.prev_holder_signed_commitment_tx {
1920                         if txid == prev_commitment.txid {
1921                                 walk_htlcs!(true, prev_commitment.htlc_outputs.iter().filter_map(|(a, _, c)| {
1922                                         if let Some(source) = c { Some((a, source)) } else { None }
1923                                 }));
1924                         }
1925                 }
1926
1927                 res
1928         }
1929
1930         pub(crate) fn get_stored_preimages(&self) -> HashMap<PaymentHash, PaymentPreimage> {
1931                 self.inner.lock().unwrap().payment_preimages.clone()
1932         }
1933 }
1934
1935 /// Compares a broadcasted commitment transaction's HTLCs with those in the latest state,
1936 /// failing any HTLCs which didn't make it into the broadcasted commitment transaction back
1937 /// after ANTI_REORG_DELAY blocks.
1938 ///
1939 /// We always compare against the set of HTLCs in counterparty commitment transactions, as those
1940 /// are the commitment transactions which are generated by us. The off-chain state machine in
1941 /// `Channel` will automatically resolve any HTLCs which were never included in a commitment
1942 /// transaction when it detects channel closure, but it is up to us to ensure any HTLCs which were
1943 /// included in a remote commitment transaction are failed back if they are not present in the
1944 /// broadcasted commitment transaction.
1945 ///
1946 /// Specifically, the removal process for HTLCs in `Channel` is always based on the counterparty
1947 /// sending a `revoke_and_ack`, which causes us to clear `prev_counterparty_commitment_txid`. Thus,
1948 /// as long as we examine both the current counterparty commitment transaction and, if it hasn't
1949 /// been revoked yet, the previous one, we we will never "forget" to resolve an HTLC.
1950 macro_rules! fail_unbroadcast_htlcs {
1951         ($self: expr, $commitment_tx_type: expr, $commitment_txid_confirmed: expr, $commitment_tx_confirmed: expr,
1952          $commitment_tx_conf_height: expr, $commitment_tx_conf_hash: expr, $confirmed_htlcs_list: expr, $logger: expr) => { {
1953                 debug_assert_eq!($commitment_tx_confirmed.txid(), $commitment_txid_confirmed);
1954
1955                 macro_rules! check_htlc_fails {
1956                         ($txid: expr, $commitment_tx: expr) => {
1957                                 if let Some(ref latest_outpoints) = $self.counterparty_claimable_outpoints.get($txid) {
1958                                         for &(ref htlc, ref source_option) in latest_outpoints.iter() {
1959                                                 if let &Some(ref source) = source_option {
1960                                                         // Check if the HTLC is present in the commitment transaction that was
1961                                                         // broadcast, but not if it was below the dust limit, which we should
1962                                                         // fail backwards immediately as there is no way for us to learn the
1963                                                         // payment_preimage.
1964                                                         // Note that if the dust limit were allowed to change between
1965                                                         // commitment transactions we'd want to be check whether *any*
1966                                                         // broadcastable commitment transaction has the HTLC in it, but it
1967                                                         // cannot currently change after channel initialization, so we don't
1968                                                         // need to here.
1969                                                         let confirmed_htlcs_iter: &mut Iterator<Item = (&HTLCOutputInCommitment, Option<&HTLCSource>)> = &mut $confirmed_htlcs_list;
1970
1971                                                         let mut matched_htlc = false;
1972                                                         for (ref broadcast_htlc, ref broadcast_source) in confirmed_htlcs_iter {
1973                                                                 if broadcast_htlc.transaction_output_index.is_some() &&
1974                                                                         (Some(&**source) == *broadcast_source ||
1975                                                                          (broadcast_source.is_none() &&
1976                                                                           broadcast_htlc.payment_hash == htlc.payment_hash &&
1977                                                                           broadcast_htlc.amount_msat == htlc.amount_msat)) {
1978                                                                         matched_htlc = true;
1979                                                                         break;
1980                                                                 }
1981                                                         }
1982                                                         if matched_htlc { continue; }
1983                                                         if $self.counterparty_fulfilled_htlcs.get(&SentHTLCId::from_source(source)).is_some() {
1984                                                                 continue;
1985                                                         }
1986                                                         $self.onchain_events_awaiting_threshold_conf.retain(|ref entry| {
1987                                                                 if entry.height != $commitment_tx_conf_height { return true; }
1988                                                                 match entry.event {
1989                                                                         OnchainEvent::HTLCUpdate { source: ref update_source, .. } => {
1990                                                                                 *update_source != **source
1991                                                                         },
1992                                                                         _ => true,
1993                                                                 }
1994                                                         });
1995                                                         let entry = OnchainEventEntry {
1996                                                                 txid: $commitment_txid_confirmed,
1997                                                                 transaction: Some($commitment_tx_confirmed.clone()),
1998                                                                 height: $commitment_tx_conf_height,
1999                                                                 block_hash: Some(*$commitment_tx_conf_hash),
2000                                                                 event: OnchainEvent::HTLCUpdate {
2001                                                                         source: (**source).clone(),
2002                                                                         payment_hash: htlc.payment_hash.clone(),
2003                                                                         htlc_value_satoshis: Some(htlc.amount_msat / 1000),
2004                                                                         commitment_tx_output_idx: None,
2005                                                                 },
2006                                                         };
2007                                                         log_trace!($logger, "Failing HTLC with payment_hash {} from {} counterparty commitment tx due to broadcast of {} commitment transaction {}, waiting for confirmation (at height {})",
2008                                                                 log_bytes!(htlc.payment_hash.0), $commitment_tx, $commitment_tx_type,
2009                                                                 $commitment_txid_confirmed, entry.confirmation_threshold());
2010                                                         $self.onchain_events_awaiting_threshold_conf.push(entry);
2011                                                 }
2012                                         }
2013                                 }
2014                         }
2015                 }
2016                 if let Some(ref txid) = $self.current_counterparty_commitment_txid {
2017                         check_htlc_fails!(txid, "current");
2018                 }
2019                 if let Some(ref txid) = $self.prev_counterparty_commitment_txid {
2020                         check_htlc_fails!(txid, "previous");
2021                 }
2022         } }
2023 }
2024
2025 // In the `test_invalid_funding_tx` test, we need a bogus script which matches the HTLC-Accepted
2026 // witness length match (ie is 136 bytes long). We generate one here which we also use in some
2027 // in-line tests later.
2028
2029 #[cfg(test)]
2030 pub fn deliberately_bogus_accepted_htlc_witness_program() -> Vec<u8> {
2031         let mut ret = [opcodes::all::OP_NOP.to_u8(); 136];
2032         ret[131] = opcodes::all::OP_DROP.to_u8();
2033         ret[132] = opcodes::all::OP_DROP.to_u8();
2034         ret[133] = opcodes::all::OP_DROP.to_u8();
2035         ret[134] = opcodes::all::OP_DROP.to_u8();
2036         ret[135] = opcodes::OP_TRUE.to_u8();
2037         Vec::from(&ret[..])
2038 }
2039
2040 #[cfg(test)]
2041 pub fn deliberately_bogus_accepted_htlc_witness() -> Vec<Vec<u8>> {
2042         vec![Vec::new(), Vec::new(), Vec::new(), Vec::new(), deliberately_bogus_accepted_htlc_witness_program().into()].into()
2043 }
2044
2045 impl<Signer: WriteableEcdsaChannelSigner> ChannelMonitorImpl<Signer> {
2046         /// Inserts a revocation secret into this channel monitor. Prunes old preimages if neither
2047         /// needed by holder commitment transactions HTCLs nor by counterparty ones. Unless we haven't already seen
2048         /// counterparty commitment transaction's secret, they are de facto pruned (we can use revocation key).
2049         fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), &'static str> {
2050                 if let Err(()) = self.commitment_secrets.provide_secret(idx, secret) {
2051                         return Err("Previous secret did not match new one");
2052                 }
2053
2054                 // Prune HTLCs from the previous counterparty commitment tx so we don't generate failure/fulfill
2055                 // events for now-revoked/fulfilled HTLCs.
2056                 if let Some(txid) = self.prev_counterparty_commitment_txid.take() {
2057                         if self.current_counterparty_commitment_txid.unwrap() != txid {
2058                                 let cur_claimables = self.counterparty_claimable_outpoints.get(
2059                                         &self.current_counterparty_commitment_txid.unwrap()).unwrap();
2060                                 for (_, ref source_opt) in self.counterparty_claimable_outpoints.get(&txid).unwrap() {
2061                                         if let Some(source) = source_opt {
2062                                                 if !cur_claimables.iter()
2063                                                         .any(|(_, cur_source_opt)| cur_source_opt == source_opt)
2064                                                 {
2065                                                         self.counterparty_fulfilled_htlcs.remove(&SentHTLCId::from_source(source));
2066                                                 }
2067                                         }
2068                                 }
2069                                 for &mut (_, ref mut source_opt) in self.counterparty_claimable_outpoints.get_mut(&txid).unwrap() {
2070                                         *source_opt = None;
2071                                 }
2072                         } else {
2073                                 assert!(cfg!(fuzzing), "Commitment txids are unique outside of fuzzing, where hashes can collide");
2074                         }
2075                 }
2076
2077                 if !self.payment_preimages.is_empty() {
2078                         let cur_holder_signed_commitment_tx = &self.current_holder_commitment_tx;
2079                         let prev_holder_signed_commitment_tx = self.prev_holder_signed_commitment_tx.as_ref();
2080                         let min_idx = self.get_min_seen_secret();
2081                         let counterparty_hash_commitment_number = &mut self.counterparty_hash_commitment_number;
2082
2083                         self.payment_preimages.retain(|&k, _| {
2084                                 for &(ref htlc, _, _) in cur_holder_signed_commitment_tx.htlc_outputs.iter() {
2085                                         if k == htlc.payment_hash {
2086                                                 return true
2087                                         }
2088                                 }
2089                                 if let Some(prev_holder_commitment_tx) = prev_holder_signed_commitment_tx {
2090                                         for &(ref htlc, _, _) in prev_holder_commitment_tx.htlc_outputs.iter() {
2091                                                 if k == htlc.payment_hash {
2092                                                         return true
2093                                                 }
2094                                         }
2095                                 }
2096                                 let contains = if let Some(cn) = counterparty_hash_commitment_number.get(&k) {
2097                                         if *cn < min_idx {
2098                                                 return true
2099                                         }
2100                                         true
2101                                 } else { false };
2102                                 if contains {
2103                                         counterparty_hash_commitment_number.remove(&k);
2104                                 }
2105                                 false
2106                         });
2107                 }
2108
2109                 Ok(())
2110         }
2111
2112         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 {
2113                 // TODO: Encrypt the htlc_outputs data with the single-hash of the commitment transaction
2114                 // so that a remote monitor doesn't learn anything unless there is a malicious close.
2115                 // (only maybe, sadly we cant do the same for local info, as we need to be aware of
2116                 // timeouts)
2117                 for &(ref htlc, _) in &htlc_outputs {
2118                         self.counterparty_hash_commitment_number.insert(htlc.payment_hash, commitment_number);
2119                 }
2120
2121                 log_trace!(logger, "Tracking new counterparty commitment transaction with txid {} at commitment number {} with {} HTLC outputs", txid, commitment_number, htlc_outputs.len());
2122                 self.prev_counterparty_commitment_txid = self.current_counterparty_commitment_txid.take();
2123                 self.current_counterparty_commitment_txid = Some(txid);
2124                 self.counterparty_claimable_outpoints.insert(txid, htlc_outputs.clone());
2125                 self.current_counterparty_commitment_number = commitment_number;
2126                 //TODO: Merge this into the other per-counterparty-transaction output storage stuff
2127                 match self.their_cur_per_commitment_points {
2128                         Some(old_points) => {
2129                                 if old_points.0 == commitment_number + 1 {
2130                                         self.their_cur_per_commitment_points = Some((old_points.0, old_points.1, Some(their_per_commitment_point)));
2131                                 } else if old_points.0 == commitment_number + 2 {
2132                                         if let Some(old_second_point) = old_points.2 {
2133                                                 self.their_cur_per_commitment_points = Some((old_points.0 - 1, old_second_point, Some(their_per_commitment_point)));
2134                                         } else {
2135                                                 self.their_cur_per_commitment_points = Some((commitment_number, their_per_commitment_point, None));
2136                                         }
2137                                 } else {
2138                                         self.their_cur_per_commitment_points = Some((commitment_number, their_per_commitment_point, None));
2139                                 }
2140                         },
2141                         None => {
2142                                 self.their_cur_per_commitment_points = Some((commitment_number, their_per_commitment_point, None));
2143                         }
2144                 }
2145                 let mut htlcs = Vec::with_capacity(htlc_outputs.len());
2146                 for htlc in htlc_outputs {
2147                         if htlc.0.transaction_output_index.is_some() {
2148                                 htlcs.push(htlc.0);
2149                         }
2150                 }
2151         }
2152
2153         /// Informs this monitor of the latest holder (ie broadcastable) commitment transaction. The
2154         /// monitor watches for timeouts and may broadcast it if we approach such a timeout. Thus, it
2155         /// is important that any clones of this channel monitor (including remote clones) by kept
2156         /// up-to-date as our holder commitment transaction is updated.
2157         /// Panics if set_on_holder_tx_csv has never been called.
2158         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> {
2159                 if htlc_outputs.iter().any(|(_, s, _)| s.is_some()) {
2160                         // If we have non-dust HTLCs in htlc_outputs, ensure they match the HTLCs in the
2161                         // `holder_commitment_tx`. In the future, we'll no longer provide the redundant data
2162                         // and just pass in source data via `nondust_htlc_sources`.
2163                         debug_assert_eq!(htlc_outputs.iter().filter(|(_, s, _)| s.is_some()).count(), holder_commitment_tx.trust().htlcs().len());
2164                         for (a, b) in htlc_outputs.iter().filter(|(_, s, _)| s.is_some()).map(|(h, _, _)| h).zip(holder_commitment_tx.trust().htlcs().iter()) {
2165                                 debug_assert_eq!(a, b);
2166                         }
2167                         debug_assert_eq!(htlc_outputs.iter().filter(|(_, s, _)| s.is_some()).count(), holder_commitment_tx.counterparty_htlc_sigs.len());
2168                         for (a, b) in htlc_outputs.iter().filter_map(|(_, s, _)| s.as_ref()).zip(holder_commitment_tx.counterparty_htlc_sigs.iter()) {
2169                                 debug_assert_eq!(a, b);
2170                         }
2171                         debug_assert!(nondust_htlc_sources.is_empty());
2172                 } else {
2173                         // If we don't have any non-dust HTLCs in htlc_outputs, assume they were all passed via
2174                         // `nondust_htlc_sources`, building up the final htlc_outputs by combining
2175                         // `nondust_htlc_sources` and the `holder_commitment_tx`
2176                         #[cfg(debug_assertions)] {
2177                                 let mut prev = -1;
2178                                 for htlc in holder_commitment_tx.trust().htlcs().iter() {
2179                                         assert!(htlc.transaction_output_index.unwrap() as i32 > prev);
2180                                         prev = htlc.transaction_output_index.unwrap() as i32;
2181                                 }
2182                         }
2183                         debug_assert!(htlc_outputs.iter().all(|(htlc, _, _)| htlc.transaction_output_index.is_none()));
2184                         debug_assert!(htlc_outputs.iter().all(|(_, sig_opt, _)| sig_opt.is_none()));
2185                         debug_assert_eq!(holder_commitment_tx.trust().htlcs().len(), holder_commitment_tx.counterparty_htlc_sigs.len());
2186
2187                         let mut sources_iter = nondust_htlc_sources.into_iter();
2188
2189                         for (htlc, counterparty_sig) in holder_commitment_tx.trust().htlcs().iter()
2190                                 .zip(holder_commitment_tx.counterparty_htlc_sigs.iter())
2191                         {
2192                                 if htlc.offered {
2193                                         let source = sources_iter.next().expect("Non-dust HTLC sources didn't match commitment tx");
2194                                         #[cfg(debug_assertions)] {
2195                                                 assert!(source.possibly_matches_output(htlc));
2196                                         }
2197                                         htlc_outputs.push((htlc.clone(), Some(counterparty_sig.clone()), Some(source)));
2198                                 } else {
2199                                         htlc_outputs.push((htlc.clone(), Some(counterparty_sig.clone()), None));
2200                                 }
2201                         }
2202                         debug_assert!(sources_iter.next().is_none());
2203                 }
2204
2205                 let trusted_tx = holder_commitment_tx.trust();
2206                 let txid = trusted_tx.txid();
2207                 let tx_keys = trusted_tx.keys();
2208                 self.current_holder_commitment_number = trusted_tx.commitment_number();
2209                 let mut new_holder_commitment_tx = HolderSignedTx {
2210                         txid,
2211                         revocation_key: tx_keys.revocation_key,
2212                         a_htlc_key: tx_keys.broadcaster_htlc_key,
2213                         b_htlc_key: tx_keys.countersignatory_htlc_key,
2214                         delayed_payment_key: tx_keys.broadcaster_delayed_payment_key,
2215                         per_commitment_point: tx_keys.per_commitment_point,
2216                         htlc_outputs,
2217                         to_self_value_sat: holder_commitment_tx.to_broadcaster_value_sat(),
2218                         feerate_per_kw: trusted_tx.feerate_per_kw(),
2219                 };
2220                 self.onchain_tx_handler.provide_latest_holder_tx(holder_commitment_tx);
2221                 mem::swap(&mut new_holder_commitment_tx, &mut self.current_holder_commitment_tx);
2222                 self.prev_holder_signed_commitment_tx = Some(new_holder_commitment_tx);
2223                 for (claimed_htlc_id, claimed_preimage) in claimed_htlcs {
2224                         #[cfg(debug_assertions)] {
2225                                 let cur_counterparty_htlcs = self.counterparty_claimable_outpoints.get(
2226                                                 &self.current_counterparty_commitment_txid.unwrap()).unwrap();
2227                                 assert!(cur_counterparty_htlcs.iter().any(|(_, source_opt)| {
2228                                         if let Some(source) = source_opt {
2229                                                 SentHTLCId::from_source(source) == *claimed_htlc_id
2230                                         } else { false }
2231                                 }));
2232                         }
2233                         self.counterparty_fulfilled_htlcs.insert(*claimed_htlc_id, *claimed_preimage);
2234                 }
2235                 if self.holder_tx_signed {
2236                         return Err("Latest holder commitment signed has already been signed, update is rejected");
2237                 }
2238                 Ok(())
2239         }
2240
2241         /// Provides a payment_hash->payment_preimage mapping. Will be automatically pruned when all
2242         /// commitment_tx_infos which contain the payment hash have been revoked.
2243         fn provide_payment_preimage<B: Deref, F: Deref, L: Deref>(
2244                 &mut self, payment_hash: &PaymentHash, payment_preimage: &PaymentPreimage, broadcaster: &B,
2245                 fee_estimator: &LowerBoundedFeeEstimator<F>, logger: &L)
2246         where B::Target: BroadcasterInterface,
2247                     F::Target: FeeEstimator,
2248                     L::Target: Logger,
2249         {
2250                 self.payment_preimages.insert(payment_hash.clone(), payment_preimage.clone());
2251
2252                 // If the channel is force closed, try to claim the output from this preimage.
2253                 // First check if a counterparty commitment transaction has been broadcasted:
2254                 macro_rules! claim_htlcs {
2255                         ($commitment_number: expr, $txid: expr) => {
2256                                 let (htlc_claim_reqs, _) = self.get_counterparty_output_claim_info($commitment_number, $txid, None);
2257                                 self.onchain_tx_handler.update_claims_view_from_requests(htlc_claim_reqs, self.best_block.height(), self.best_block.height(), broadcaster, fee_estimator, logger);
2258                         }
2259                 }
2260                 if let Some(txid) = self.current_counterparty_commitment_txid {
2261                         if let Some(commitment_number) = self.counterparty_commitment_txn_on_chain.get(&txid) {
2262                                 claim_htlcs!(*commitment_number, txid);
2263                                 return;
2264                         }
2265                 }
2266                 if let Some(txid) = self.prev_counterparty_commitment_txid {
2267                         if let Some(commitment_number) = self.counterparty_commitment_txn_on_chain.get(&txid) {
2268                                 claim_htlcs!(*commitment_number, txid);
2269                                 return;
2270                         }
2271                 }
2272
2273                 // Then if a holder commitment transaction has been seen on-chain, broadcast transactions
2274                 // claiming the HTLC output from each of the holder commitment transactions.
2275                 // Note that we can't just use `self.holder_tx_signed`, because that only covers the case where
2276                 // *we* sign a holder commitment transaction, not when e.g. a watchtower broadcasts one of our
2277                 // holder commitment transactions.
2278                 if self.broadcasted_holder_revokable_script.is_some() {
2279                         // Assume that the broadcasted commitment transaction confirmed in the current best
2280                         // block. Even if not, its a reasonable metric for the bump criteria on the HTLC
2281                         // transactions.
2282                         let (claim_reqs, _) = self.get_broadcasted_holder_claims(&self.current_holder_commitment_tx, self.best_block.height());
2283                         self.onchain_tx_handler.update_claims_view_from_requests(claim_reqs, self.best_block.height(), self.best_block.height(), broadcaster, fee_estimator, logger);
2284                         if let Some(ref tx) = self.prev_holder_signed_commitment_tx {
2285                                 let (claim_reqs, _) = self.get_broadcasted_holder_claims(&tx, self.best_block.height());
2286                                 self.onchain_tx_handler.update_claims_view_from_requests(claim_reqs, self.best_block.height(), self.best_block.height(), broadcaster, fee_estimator, logger);
2287                         }
2288                 }
2289         }
2290
2291         pub(crate) fn broadcast_latest_holder_commitment_txn<B: Deref, L: Deref>(&mut self, broadcaster: &B, logger: &L)
2292                 where B::Target: BroadcasterInterface,
2293                                         L::Target: Logger,
2294         {
2295                 for tx in self.get_latest_holder_commitment_txn(logger).iter() {
2296                         log_info!(logger, "Broadcasting local {}", log_tx!(tx));
2297                         broadcaster.broadcast_transaction(tx);
2298                 }
2299                 self.pending_monitor_events.push(MonitorEvent::CommitmentTxConfirmed(self.funding_info.0));
2300         }
2301
2302         pub fn update_monitor<B: Deref, F: Deref, L: Deref>(&mut self, updates: &ChannelMonitorUpdate, broadcaster: &B, fee_estimator: F, logger: &L) -> Result<(), ()>
2303         where B::Target: BroadcasterInterface,
2304                 F::Target: FeeEstimator,
2305                 L::Target: Logger,
2306         {
2307                 log_info!(logger, "Applying update to monitor {}, bringing update_id from {} to {} with {} changes.",
2308                         log_funding_info!(self), self.latest_update_id, updates.update_id, updates.updates.len());
2309                 // ChannelMonitor updates may be applied after force close if we receive a preimage for a
2310                 // broadcasted commitment transaction HTLC output that we'd like to claim on-chain. If this
2311                 // is the case, we no longer have guaranteed access to the monitor's update ID, so we use a
2312                 // sentinel value instead.
2313                 //
2314                 // The `ChannelManager` may also queue redundant `ChannelForceClosed` updates if it still
2315                 // thinks the channel needs to have its commitment transaction broadcast, so we'll allow
2316                 // them as well.
2317                 if updates.update_id == CLOSED_CHANNEL_UPDATE_ID {
2318                         assert_eq!(updates.updates.len(), 1);
2319                         match updates.updates[0] {
2320                                 ChannelMonitorUpdateStep::ChannelForceClosed { .. } => {},
2321                                 // We should have already seen a `ChannelForceClosed` update if we're trying to
2322                                 // provide a preimage at this point.
2323                                 ChannelMonitorUpdateStep::PaymentPreimage { .. } =>
2324                                         debug_assert_eq!(self.latest_update_id, CLOSED_CHANNEL_UPDATE_ID),
2325                                 _ => {
2326                                         log_error!(logger, "Attempted to apply post-force-close ChannelMonitorUpdate of type {}", updates.updates[0].variant_name());
2327                                         panic!("Attempted to apply post-force-close ChannelMonitorUpdate that wasn't providing a payment preimage");
2328                                 },
2329                         }
2330                 } else if self.latest_update_id + 1 != updates.update_id {
2331                         panic!("Attempted to apply ChannelMonitorUpdates out of order, check the update_id before passing an update to update_monitor!");
2332                 }
2333                 let mut ret = Ok(());
2334                 let bounded_fee_estimator = LowerBoundedFeeEstimator::new(&*fee_estimator);
2335                 for update in updates.updates.iter() {
2336                         match update {
2337                                 ChannelMonitorUpdateStep::LatestHolderCommitmentTXInfo { commitment_tx, htlc_outputs, claimed_htlcs, nondust_htlc_sources } => {
2338                                         log_trace!(logger, "Updating ChannelMonitor with latest holder commitment transaction info");
2339                                         if self.lockdown_from_offchain { panic!(); }
2340                                         if let Err(e) = self.provide_latest_holder_commitment_tx(commitment_tx.clone(), htlc_outputs.clone(), &claimed_htlcs, nondust_htlc_sources.clone()) {
2341                                                 log_error!(logger, "Providing latest holder commitment transaction failed/was refused:");
2342                                                 log_error!(logger, "    {}", e);
2343                                                 ret = Err(());
2344                                         }
2345                                 }
2346                                 ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo { commitment_txid, htlc_outputs, commitment_number, their_per_commitment_point } => {
2347                                         log_trace!(logger, "Updating ChannelMonitor with latest counterparty commitment transaction info");
2348                                         self.provide_latest_counterparty_commitment_tx(*commitment_txid, htlc_outputs.clone(), *commitment_number, *their_per_commitment_point, logger)
2349                                 },
2350                                 ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage } => {
2351                                         log_trace!(logger, "Updating ChannelMonitor with payment preimage");
2352                                         self.provide_payment_preimage(&PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()), &payment_preimage, broadcaster, &bounded_fee_estimator, logger)
2353                                 },
2354                                 ChannelMonitorUpdateStep::CommitmentSecret { idx, secret } => {
2355                                         log_trace!(logger, "Updating ChannelMonitor with commitment secret");
2356                                         if let Err(e) = self.provide_secret(*idx, *secret) {
2357                                                 log_error!(logger, "Providing latest counterparty commitment secret failed/was refused:");
2358                                                 log_error!(logger, "    {}", e);
2359                                                 ret = Err(());
2360                                         }
2361                                 },
2362                                 ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast } => {
2363                                         log_trace!(logger, "Updating ChannelMonitor: channel force closed, should broadcast: {}", should_broadcast);
2364                                         self.lockdown_from_offchain = true;
2365                                         if *should_broadcast {
2366                                                 // There's no need to broadcast our commitment transaction if we've seen one
2367                                                 // confirmed (even with 1 confirmation) as it'll be rejected as
2368                                                 // duplicate/conflicting.
2369                                                 let detected_funding_spend = self.funding_spend_confirmed.is_some() ||
2370                                                         self.onchain_events_awaiting_threshold_conf.iter().find(|event| match event.event {
2371                                                                 OnchainEvent::FundingSpendConfirmation { .. } => true,
2372                                                                 _ => false,
2373                                                         }).is_some();
2374                                                 if detected_funding_spend {
2375                                                         continue;
2376                                                 }
2377                                                 self.broadcast_latest_holder_commitment_txn(broadcaster, logger);
2378                                                 // If the channel supports anchor outputs, we'll need to emit an external
2379                                                 // event to be consumed such that a child transaction is broadcast with a
2380                                                 // high enough feerate for the parent commitment transaction to confirm.
2381                                                 if self.onchain_tx_handler.opt_anchors() {
2382                                                         let funding_output = HolderFundingOutput::build(
2383                                                                 self.funding_redeemscript.clone(), self.channel_value_satoshis,
2384                                                                 self.onchain_tx_handler.opt_anchors(),
2385                                                         );
2386                                                         let best_block_height = self.best_block.height();
2387                                                         let commitment_package = PackageTemplate::build_package(
2388                                                                 self.funding_info.0.txid.clone(), self.funding_info.0.index as u32,
2389                                                                 PackageSolvingData::HolderFundingOutput(funding_output),
2390                                                                 best_block_height, false, best_block_height,
2391                                                         );
2392                                                         self.onchain_tx_handler.update_claims_view_from_requests(
2393                                                                 vec![commitment_package], best_block_height, best_block_height,
2394                                                                 broadcaster, &bounded_fee_estimator, logger,
2395                                                         );
2396                                                 }
2397                                         } else if !self.holder_tx_signed {
2398                                                 log_error!(logger, "WARNING: You have a potentially-unsafe holder commitment transaction available to broadcast");
2399                                                 log_error!(logger, "    in channel monitor for channel {}!", log_bytes!(self.funding_info.0.to_channel_id()));
2400                                                 log_error!(logger, "    Read the docs for ChannelMonitor::get_latest_holder_commitment_txn and take manual action!");
2401                                         } else {
2402                                                 // If we generated a MonitorEvent::CommitmentTxConfirmed, the ChannelManager
2403                                                 // will still give us a ChannelForceClosed event with !should_broadcast, but we
2404                                                 // shouldn't print the scary warning above.
2405                                                 log_info!(logger, "Channel off-chain state closed after we broadcasted our latest commitment transaction.");
2406                                         }
2407                                 },
2408                                 ChannelMonitorUpdateStep::ShutdownScript { scriptpubkey } => {
2409                                         log_trace!(logger, "Updating ChannelMonitor with shutdown script");
2410                                         if let Some(shutdown_script) = self.shutdown_script.replace(scriptpubkey.clone()) {
2411                                                 panic!("Attempted to replace shutdown script {} with {}", shutdown_script, scriptpubkey);
2412                                         }
2413                                 },
2414                         }
2415                 }
2416
2417                 // If the updates succeeded and we were in an already closed channel state, then there's no
2418                 // need to refuse any updates we expect to receive afer seeing a confirmed commitment.
2419                 if ret.is_ok() && updates.update_id == CLOSED_CHANNEL_UPDATE_ID && self.latest_update_id == updates.update_id {
2420                         return Ok(());
2421                 }
2422
2423                 self.latest_update_id = updates.update_id;
2424
2425                 if ret.is_ok() && self.funding_spend_seen {
2426                         log_error!(logger, "Refusing Channel Monitor Update as counterparty attempted to update commitment after funding was spent");
2427                         Err(())
2428                 } else { ret }
2429         }
2430
2431         pub fn get_latest_update_id(&self) -> u64 {
2432                 self.latest_update_id
2433         }
2434
2435         pub fn get_funding_txo(&self) -> &(OutPoint, Script) {
2436                 &self.funding_info
2437         }
2438
2439         pub fn get_outputs_to_watch(&self) -> &HashMap<Txid, Vec<(u32, Script)>> {
2440                 // If we've detected a counterparty commitment tx on chain, we must include it in the set
2441                 // of outputs to watch for spends of, otherwise we're likely to lose user funds. Because
2442                 // its trivial to do, double-check that here.
2443                 for (txid, _) in self.counterparty_commitment_txn_on_chain.iter() {
2444                         self.outputs_to_watch.get(txid).expect("Counterparty commitment txn which have been broadcast should have outputs registered");
2445                 }
2446                 &self.outputs_to_watch
2447         }
2448
2449         pub fn get_and_clear_pending_monitor_events(&mut self) -> Vec<MonitorEvent> {
2450                 let mut ret = Vec::new();
2451                 mem::swap(&mut ret, &mut self.pending_monitor_events);
2452                 ret
2453         }
2454
2455         pub fn get_and_clear_pending_events(&mut self) -> Vec<Event> {
2456                 let mut ret = Vec::new();
2457                 mem::swap(&mut ret, &mut self.pending_events);
2458                 #[cfg(anchors)]
2459                 for claim_event in self.onchain_tx_handler.get_and_clear_pending_claim_events().drain(..) {
2460                         match claim_event {
2461                                 ClaimEvent::BumpCommitment {
2462                                         package_target_feerate_sat_per_1000_weight, commitment_tx, anchor_output_idx,
2463                                 } => {
2464                                         let commitment_txid = commitment_tx.txid();
2465                                         debug_assert_eq!(self.current_holder_commitment_tx.txid, commitment_txid);
2466                                         let pending_htlcs = self.current_holder_commitment_tx.non_dust_htlcs();
2467                                         let commitment_tx_fee_satoshis = self.channel_value_satoshis -
2468                                                 commitment_tx.output.iter().fold(0u64, |sum, output| sum + output.value);
2469                                         ret.push(Event::BumpTransaction(BumpTransactionEvent::ChannelClose {
2470                                                 package_target_feerate_sat_per_1000_weight,
2471                                                 commitment_tx,
2472                                                 commitment_tx_fee_satoshis,
2473                                                 anchor_descriptor: AnchorDescriptor {
2474                                                         channel_keys_id: self.channel_keys_id,
2475                                                         channel_value_satoshis: self.channel_value_satoshis,
2476                                                         outpoint: BitcoinOutPoint {
2477                                                                 txid: commitment_txid,
2478                                                                 vout: anchor_output_idx,
2479                                                         },
2480                                                 },
2481                                                 pending_htlcs,
2482                                         }));
2483                                 },
2484                                 ClaimEvent::BumpHTLC {
2485                                         target_feerate_sat_per_1000_weight, htlcs, tx_lock_time,
2486                                 } => {
2487                                         let mut htlc_descriptors = Vec::with_capacity(htlcs.len());
2488                                         for htlc in htlcs {
2489                                                 htlc_descriptors.push(HTLCDescriptor {
2490                                                         channel_keys_id: self.channel_keys_id,
2491                                                         channel_value_satoshis: self.channel_value_satoshis,
2492                                                         channel_parameters: self.onchain_tx_handler.channel_transaction_parameters.clone(),
2493                                                         commitment_txid: htlc.commitment_txid,
2494                                                         per_commitment_number: htlc.per_commitment_number,
2495                                                         htlc: htlc.htlc,
2496                                                         preimage: htlc.preimage,
2497                                                         counterparty_sig: htlc.counterparty_sig,
2498                                                 });
2499                                         }
2500                                         ret.push(Event::BumpTransaction(BumpTransactionEvent::HTLCResolution {
2501                                                 target_feerate_sat_per_1000_weight,
2502                                                 htlc_descriptors,
2503                                                 tx_lock_time,
2504                                         }));
2505                                 }
2506                         }
2507                 }
2508                 ret
2509         }
2510
2511         /// Can only fail if idx is < get_min_seen_secret
2512         fn get_secret(&self, idx: u64) -> Option<[u8; 32]> {
2513                 self.commitment_secrets.get_secret(idx)
2514         }
2515
2516         pub(crate) fn get_min_seen_secret(&self) -> u64 {
2517                 self.commitment_secrets.get_min_seen_secret()
2518         }
2519
2520         pub(crate) fn get_cur_counterparty_commitment_number(&self) -> u64 {
2521                 self.current_counterparty_commitment_number
2522         }
2523
2524         pub(crate) fn get_cur_holder_commitment_number(&self) -> u64 {
2525                 self.current_holder_commitment_number
2526         }
2527
2528         /// Attempts to claim a counterparty commitment transaction's outputs using the revocation key and
2529         /// data in counterparty_claimable_outpoints. Will directly claim any HTLC outputs which expire at a
2530         /// height > height + CLTV_SHARED_CLAIM_BUFFER. In any case, will install monitoring for
2531         /// HTLC-Success/HTLC-Timeout transactions.
2532         ///
2533         /// Returns packages to claim the revoked output(s), as well as additional outputs to watch and
2534         /// general information about the output that is to the counterparty in the commitment
2535         /// transaction.
2536         fn check_spend_counterparty_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, block_hash: &BlockHash, logger: &L)
2537                 -> (Vec<PackageTemplate>, TransactionOutputs, CommitmentTxCounterpartyOutputInfo)
2538         where L::Target: Logger {
2539                 // Most secp and related errors trying to create keys means we have no hope of constructing
2540                 // a spend transaction...so we return no transactions to broadcast
2541                 let mut claimable_outpoints = Vec::new();
2542                 let mut watch_outputs = Vec::new();
2543                 let mut to_counterparty_output_info = None;
2544
2545                 let commitment_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
2546                 let per_commitment_option = self.counterparty_claimable_outpoints.get(&commitment_txid);
2547
2548                 macro_rules! ignore_error {
2549                         ( $thing : expr ) => {
2550                                 match $thing {
2551                                         Ok(a) => a,
2552                                         Err(_) => return (claimable_outpoints, (commitment_txid, watch_outputs), to_counterparty_output_info)
2553                                 }
2554                         };
2555                 }
2556
2557                 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);
2558                 if commitment_number >= self.get_min_seen_secret() {
2559                         let secret = self.get_secret(commitment_number).unwrap();
2560                         let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
2561                         let per_commitment_point = PublicKey::from_secret_key(&self.onchain_tx_handler.secp_ctx, &per_commitment_key);
2562                         let revocation_pubkey = chan_utils::derive_public_revocation_key(&self.onchain_tx_handler.secp_ctx, &per_commitment_point, &self.holder_revocation_basepoint);
2563                         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);
2564
2565                         let revokeable_redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.counterparty_commitment_params.on_counterparty_tx_csv, &delayed_key);
2566                         let revokeable_p2wsh = revokeable_redeemscript.to_v0_p2wsh();
2567
2568                         // First, process non-htlc outputs (to_holder & to_counterparty)
2569                         for (idx, outp) in tx.output.iter().enumerate() {
2570                                 if outp.script_pubkey == revokeable_p2wsh {
2571                                         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);
2572                                         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, true, height);
2573                                         claimable_outpoints.push(justice_package);
2574                                         to_counterparty_output_info =
2575                                                 Some((idx.try_into().expect("Txn can't have more than 2^32 outputs"), outp.value));
2576                                 }
2577                         }
2578
2579                         // Then, try to find revoked htlc outputs
2580                         if let Some(ref per_commitment_data) = per_commitment_option {
2581                                 for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
2582                                         if let Some(transaction_output_index) = htlc.transaction_output_index {
2583                                                 if transaction_output_index as usize >= tx.output.len() ||
2584                                                                 tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
2585                                                         // per_commitment_data is corrupt or our commitment signing key leaked!
2586                                                         return (claimable_outpoints, (commitment_txid, watch_outputs),
2587                                                                 to_counterparty_output_info);
2588                                                 }
2589                                                 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());
2590                                                 let justice_package = PackageTemplate::build_package(commitment_txid, transaction_output_index, PackageSolvingData::RevokedHTLCOutput(revk_htlc_outp), htlc.cltv_expiry, true, height);
2591                                                 claimable_outpoints.push(justice_package);
2592                                         }
2593                                 }
2594                         }
2595
2596                         // Last, track onchain revoked commitment transaction and fail backward outgoing HTLCs as payment path is broken
2597                         if !claimable_outpoints.is_empty() || per_commitment_option.is_some() { // ie we're confident this is actually ours
2598                                 // We're definitely a counterparty commitment transaction!
2599                                 log_error!(logger, "Got broadcast of revoked counterparty commitment transaction, going to generate general spend tx with {} inputs", claimable_outpoints.len());
2600                                 for (idx, outp) in tx.output.iter().enumerate() {
2601                                         watch_outputs.push((idx as u32, outp.clone()));
2602                                 }
2603                                 self.counterparty_commitment_txn_on_chain.insert(commitment_txid, commitment_number);
2604
2605                                 if let Some(per_commitment_data) = per_commitment_option {
2606                                         fail_unbroadcast_htlcs!(self, "revoked_counterparty", commitment_txid, tx, height,
2607                                                 block_hash, per_commitment_data.iter().map(|(htlc, htlc_source)|
2608                                                         (htlc, htlc_source.as_ref().map(|htlc_source| htlc_source.as_ref()))
2609                                                 ), logger);
2610                                 } else {
2611                                         debug_assert!(false, "We should have per-commitment option for any recognized old commitment txn");
2612                                         fail_unbroadcast_htlcs!(self, "revoked counterparty", commitment_txid, tx, height,
2613                                                 block_hash, [].iter().map(|reference| *reference), logger);
2614                                 }
2615                         }
2616                 } else if let Some(per_commitment_data) = per_commitment_option {
2617                         // While this isn't useful yet, there is a potential race where if a counterparty
2618                         // revokes a state at the same time as the commitment transaction for that state is
2619                         // confirmed, and the watchtower receives the block before the user, the user could
2620                         // upload a new ChannelMonitor with the revocation secret but the watchtower has
2621                         // already processed the block, resulting in the counterparty_commitment_txn_on_chain entry
2622                         // not being generated by the above conditional. Thus, to be safe, we go ahead and
2623                         // insert it here.
2624                         for (idx, outp) in tx.output.iter().enumerate() {
2625                                 watch_outputs.push((idx as u32, outp.clone()));
2626                         }
2627                         self.counterparty_commitment_txn_on_chain.insert(commitment_txid, commitment_number);
2628
2629                         log_info!(logger, "Got broadcast of non-revoked counterparty commitment transaction {}", commitment_txid);
2630                         fail_unbroadcast_htlcs!(self, "counterparty", commitment_txid, tx, height, block_hash,
2631                                 per_commitment_data.iter().map(|(htlc, htlc_source)|
2632                                         (htlc, htlc_source.as_ref().map(|htlc_source| htlc_source.as_ref()))
2633                                 ), logger);
2634
2635                         let (htlc_claim_reqs, counterparty_output_info) =
2636                                 self.get_counterparty_output_claim_info(commitment_number, commitment_txid, Some(tx));
2637                         to_counterparty_output_info = counterparty_output_info;
2638                         for req in htlc_claim_reqs {
2639                                 claimable_outpoints.push(req);
2640                         }
2641
2642                 }
2643                 (claimable_outpoints, (commitment_txid, watch_outputs), to_counterparty_output_info)
2644         }
2645
2646         /// Returns the HTLC claim package templates and the counterparty output info
2647         fn get_counterparty_output_claim_info(&self, commitment_number: u64, commitment_txid: Txid, tx: Option<&Transaction>)
2648         -> (Vec<PackageTemplate>, CommitmentTxCounterpartyOutputInfo) {
2649                 let mut claimable_outpoints = Vec::new();
2650                 let mut to_counterparty_output_info: CommitmentTxCounterpartyOutputInfo = None;
2651
2652                 let htlc_outputs = match self.counterparty_claimable_outpoints.get(&commitment_txid) {
2653                         Some(outputs) => outputs,
2654                         None => return (claimable_outpoints, to_counterparty_output_info),
2655                 };
2656                 let per_commitment_points = match self.their_cur_per_commitment_points {
2657                         Some(points) => points,
2658                         None => return (claimable_outpoints, to_counterparty_output_info),
2659                 };
2660
2661                 let per_commitment_point =
2662                         // If the counterparty commitment tx is the latest valid state, use their latest
2663                         // per-commitment point
2664                         if per_commitment_points.0 == commitment_number { &per_commitment_points.1 }
2665                         else if let Some(point) = per_commitment_points.2.as_ref() {
2666                                 // If counterparty commitment tx is the state previous to the latest valid state, use
2667                                 // their previous per-commitment point (non-atomicity of revocation means it's valid for
2668                                 // them to temporarily have two valid commitment txns from our viewpoint)
2669                                 if per_commitment_points.0 == commitment_number + 1 {
2670                                         point
2671                                 } else { return (claimable_outpoints, to_counterparty_output_info); }
2672                         } else { return (claimable_outpoints, to_counterparty_output_info); };
2673
2674                 if let Some(transaction) = tx {
2675                         let revocation_pubkey = chan_utils::derive_public_revocation_key(
2676                                 &self.onchain_tx_handler.secp_ctx, &per_commitment_point, &self.holder_revocation_basepoint);
2677                         let delayed_key = chan_utils::derive_public_key(&self.onchain_tx_handler.secp_ctx,
2678                                 &per_commitment_point,
2679                                 &self.counterparty_commitment_params.counterparty_delayed_payment_base_key);
2680                         let revokeable_p2wsh = chan_utils::get_revokeable_redeemscript(&revocation_pubkey,
2681                                 self.counterparty_commitment_params.on_counterparty_tx_csv,
2682                                 &delayed_key).to_v0_p2wsh();
2683                         for (idx, outp) in transaction.output.iter().enumerate() {
2684                                 if outp.script_pubkey == revokeable_p2wsh {
2685                                         to_counterparty_output_info =
2686                                                 Some((idx.try_into().expect("Can't have > 2^32 outputs"), outp.value));
2687                                 }
2688                         }
2689                 }
2690
2691                 for (_, &(ref htlc, _)) in htlc_outputs.iter().enumerate() {
2692                         if let Some(transaction_output_index) = htlc.transaction_output_index {
2693                                 if let Some(transaction) = tx {
2694                                         if transaction_output_index as usize >= transaction.output.len() ||
2695                                                 transaction.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
2696                                                         // per_commitment_data is corrupt or our commitment signing key leaked!
2697                                                         return (claimable_outpoints, to_counterparty_output_info);
2698                                                 }
2699                                 }
2700                                 let preimage = if htlc.offered { if let Some(p) = self.payment_preimages.get(&htlc.payment_hash) { Some(*p) } else { None } } else { None };
2701                                 if preimage.is_some() || !htlc.offered {
2702                                         let counterparty_htlc_outp = if htlc.offered {
2703                                                 PackageSolvingData::CounterpartyOfferedHTLCOutput(
2704                                                         CounterpartyOfferedHTLCOutput::build(*per_commitment_point,
2705                                                                 self.counterparty_commitment_params.counterparty_delayed_payment_base_key,
2706                                                                 self.counterparty_commitment_params.counterparty_htlc_base_key,
2707                                                                 preimage.unwrap(), htlc.clone(), self.onchain_tx_handler.opt_anchors()))
2708                                         } else {
2709                                                 PackageSolvingData::CounterpartyReceivedHTLCOutput(
2710                                                         CounterpartyReceivedHTLCOutput::build(*per_commitment_point,
2711                                                                 self.counterparty_commitment_params.counterparty_delayed_payment_base_key,
2712                                                                 self.counterparty_commitment_params.counterparty_htlc_base_key,
2713                                                                 htlc.clone(), self.onchain_tx_handler.opt_anchors()))
2714                                         };
2715                                         let aggregation = if !htlc.offered { false } else { true };
2716                                         let counterparty_package = PackageTemplate::build_package(commitment_txid, transaction_output_index, counterparty_htlc_outp, htlc.cltv_expiry,aggregation, 0);
2717                                         claimable_outpoints.push(counterparty_package);
2718                                 }
2719                         }
2720                 }
2721
2722                 (claimable_outpoints, to_counterparty_output_info)
2723         }
2724
2725         /// Attempts to claim a counterparty HTLC-Success/HTLC-Timeout's outputs using the revocation key
2726         fn check_spend_counterparty_htlc<L: Deref>(
2727                 &mut self, tx: &Transaction, commitment_number: u64, commitment_txid: &Txid, height: u32, logger: &L
2728         ) -> (Vec<PackageTemplate>, Option<TransactionOutputs>) where L::Target: Logger {
2729                 let secret = if let Some(secret) = self.get_secret(commitment_number) { secret } else { return (Vec::new(), None); };
2730                 let per_commitment_key = match SecretKey::from_slice(&secret) {
2731                         Ok(key) => key,
2732                         Err(_) => return (Vec::new(), None)
2733                 };
2734                 let per_commitment_point = PublicKey::from_secret_key(&self.onchain_tx_handler.secp_ctx, &per_commitment_key);
2735
2736                 let htlc_txid = tx.txid();
2737                 let mut claimable_outpoints = vec![];
2738                 let mut outputs_to_watch = None;
2739                 // Previously, we would only claim HTLCs from revoked HTLC transactions if they had 1 input
2740                 // with a witness of 5 elements and 1 output. This wasn't enough for anchor outputs, as the
2741                 // counterparty can now aggregate multiple HTLCs into a single transaction thanks to
2742                 // `SIGHASH_SINGLE` remote signatures, leading us to not claim any HTLCs upon seeing a
2743                 // confirmed revoked HTLC transaction (for more details, see
2744                 // https://lists.linuxfoundation.org/pipermail/lightning-dev/2022-April/003561.html).
2745                 //
2746                 // We make sure we're not vulnerable to this case by checking all inputs of the transaction,
2747                 // and claim those which spend the commitment transaction, have a witness of 5 elements, and
2748                 // have a corresponding output at the same index within the transaction.
2749                 for (idx, input) in tx.input.iter().enumerate() {
2750                         if input.previous_output.txid == *commitment_txid && input.witness.len() == 5 && tx.output.get(idx).is_some() {
2751                                 log_error!(logger, "Got broadcast of revoked counterparty HTLC transaction, spending {}:{}", htlc_txid, idx);
2752                                 let revk_outp = RevokedOutput::build(
2753                                         per_commitment_point, self.counterparty_commitment_params.counterparty_delayed_payment_base_key,
2754                                         self.counterparty_commitment_params.counterparty_htlc_base_key, per_commitment_key,
2755                                         tx.output[idx].value, self.counterparty_commitment_params.on_counterparty_tx_csv
2756                                 );
2757                                 let justice_package = PackageTemplate::build_package(
2758                                         htlc_txid, idx as u32, PackageSolvingData::RevokedOutput(revk_outp),
2759                                         height + self.counterparty_commitment_params.on_counterparty_tx_csv as u32, true, height
2760                                 );
2761                                 claimable_outpoints.push(justice_package);
2762                                 if outputs_to_watch.is_none() {
2763                                         outputs_to_watch = Some((htlc_txid, vec![]));
2764                                 }
2765                                 outputs_to_watch.as_mut().unwrap().1.push((idx as u32, tx.output[idx].clone()));
2766                         }
2767                 }
2768                 (claimable_outpoints, outputs_to_watch)
2769         }
2770
2771         // Returns (1) `PackageTemplate`s that can be given to the OnchainTxHandler, so that the handler can
2772         // broadcast transactions claiming holder HTLC commitment outputs and (2) a holder revokable
2773         // script so we can detect whether a holder transaction has been seen on-chain.
2774         fn get_broadcasted_holder_claims(&self, holder_tx: &HolderSignedTx, conf_height: u32) -> (Vec<PackageTemplate>, Option<(Script, PublicKey, PublicKey)>) {
2775                 let mut claim_requests = Vec::with_capacity(holder_tx.htlc_outputs.len());
2776
2777                 let redeemscript = chan_utils::get_revokeable_redeemscript(&holder_tx.revocation_key, self.on_holder_tx_csv, &holder_tx.delayed_payment_key);
2778                 let broadcasted_holder_revokable_script = Some((redeemscript.to_v0_p2wsh(), holder_tx.per_commitment_point.clone(), holder_tx.revocation_key.clone()));
2779
2780                 for &(ref htlc, _, _) in holder_tx.htlc_outputs.iter() {
2781                         if let Some(transaction_output_index) = htlc.transaction_output_index {
2782                                 let (htlc_output, aggregable) = if htlc.offered {
2783                                         let htlc_output = HolderHTLCOutput::build_offered(
2784                                                 htlc.amount_msat, htlc.cltv_expiry, self.onchain_tx_handler.opt_anchors()
2785                                         );
2786                                         (htlc_output, false)
2787                                 } else {
2788                                         let payment_preimage = if let Some(preimage) = self.payment_preimages.get(&htlc.payment_hash) {
2789                                                 preimage.clone()
2790                                         } else {
2791                                                 // We can't build an HTLC-Success transaction without the preimage
2792                                                 continue;
2793                                         };
2794                                         let htlc_output = HolderHTLCOutput::build_accepted(
2795                                                 payment_preimage, htlc.amount_msat, self.onchain_tx_handler.opt_anchors()
2796                                         );
2797                                         (htlc_output, self.onchain_tx_handler.opt_anchors())
2798                                 };
2799                                 let htlc_package = PackageTemplate::build_package(
2800                                         holder_tx.txid, transaction_output_index,
2801                                         PackageSolvingData::HolderHTLCOutput(htlc_output),
2802                                         htlc.cltv_expiry, aggregable, conf_height
2803                                 );
2804                                 claim_requests.push(htlc_package);
2805                         }
2806                 }
2807
2808                 (claim_requests, broadcasted_holder_revokable_script)
2809         }
2810
2811         // Returns holder HTLC outputs to watch and react to in case of spending.
2812         fn get_broadcasted_holder_watch_outputs(&self, holder_tx: &HolderSignedTx, commitment_tx: &Transaction) -> Vec<(u32, TxOut)> {
2813                 let mut watch_outputs = Vec::with_capacity(holder_tx.htlc_outputs.len());
2814                 for &(ref htlc, _, _) in holder_tx.htlc_outputs.iter() {
2815                         if let Some(transaction_output_index) = htlc.transaction_output_index {
2816                                 watch_outputs.push((transaction_output_index, commitment_tx.output[transaction_output_index as usize].clone()));
2817                         }
2818                 }
2819                 watch_outputs
2820         }
2821
2822         /// Attempts to claim any claimable HTLCs in a commitment transaction which was not (yet)
2823         /// revoked using data in holder_claimable_outpoints.
2824         /// Should not be used if check_spend_revoked_transaction succeeds.
2825         /// Returns None unless the transaction is definitely one of our commitment transactions.
2826         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 {
2827                 let commitment_txid = tx.txid();
2828                 let mut claim_requests = Vec::new();
2829                 let mut watch_outputs = Vec::new();
2830
2831                 macro_rules! append_onchain_update {
2832                         ($updates: expr, $to_watch: expr) => {
2833                                 claim_requests = $updates.0;
2834                                 self.broadcasted_holder_revokable_script = $updates.1;
2835                                 watch_outputs.append(&mut $to_watch);
2836                         }
2837                 }
2838
2839                 // HTLCs set may differ between last and previous holder commitment txn, in case of one them hitting chain, ensure we cancel all HTLCs backward
2840                 let mut is_holder_tx = false;
2841
2842                 if self.current_holder_commitment_tx.txid == commitment_txid {
2843                         is_holder_tx = true;
2844                         log_info!(logger, "Got broadcast of latest holder commitment tx {}, searching for available HTLCs to claim", commitment_txid);
2845                         let res = self.get_broadcasted_holder_claims(&self.current_holder_commitment_tx, height);
2846                         let mut to_watch = self.get_broadcasted_holder_watch_outputs(&self.current_holder_commitment_tx, tx);
2847                         append_onchain_update!(res, to_watch);
2848                         fail_unbroadcast_htlcs!(self, "latest holder", commitment_txid, tx, height,
2849                                 block_hash, self.current_holder_commitment_tx.htlc_outputs.iter()
2850                                 .map(|(htlc, _, htlc_source)| (htlc, htlc_source.as_ref())), logger);
2851                 } else if let &Some(ref holder_tx) = &self.prev_holder_signed_commitment_tx {
2852                         if holder_tx.txid == commitment_txid {
2853                                 is_holder_tx = true;
2854                                 log_info!(logger, "Got broadcast of previous holder commitment tx {}, searching for available HTLCs to claim", commitment_txid);
2855                                 let res = self.get_broadcasted_holder_claims(holder_tx, height);
2856                                 let mut to_watch = self.get_broadcasted_holder_watch_outputs(holder_tx, tx);
2857                                 append_onchain_update!(res, to_watch);
2858                                 fail_unbroadcast_htlcs!(self, "previous holder", commitment_txid, tx, height, block_hash,
2859                                         holder_tx.htlc_outputs.iter().map(|(htlc, _, htlc_source)| (htlc, htlc_source.as_ref())),
2860                                         logger);
2861                         }
2862                 }
2863
2864                 if is_holder_tx {
2865                         Some((claim_requests, (commitment_txid, watch_outputs)))
2866                 } else {
2867                         None
2868                 }
2869         }
2870
2871         pub fn get_latest_holder_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
2872                 log_debug!(logger, "Getting signed latest holder commitment transaction!");
2873                 self.holder_tx_signed = true;
2874                 let commitment_tx = self.onchain_tx_handler.get_fully_signed_holder_tx(&self.funding_redeemscript);
2875                 let txid = commitment_tx.txid();
2876                 let mut holder_transactions = vec![commitment_tx];
2877                 // When anchor outputs are present, the HTLC transactions are only valid once the commitment
2878                 // transaction confirms.
2879                 if self.onchain_tx_handler.opt_anchors() {
2880                         return holder_transactions;
2881                 }
2882                 for htlc in self.current_holder_commitment_tx.htlc_outputs.iter() {
2883                         if let Some(vout) = htlc.0.transaction_output_index {
2884                                 let preimage = if !htlc.0.offered {
2885                                         if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
2886                                                 // We can't build an HTLC-Success transaction without the preimage
2887                                                 continue;
2888                                         }
2889                                 } else if htlc.0.cltv_expiry > self.best_block.height() + 1 {
2890                                         // Don't broadcast HTLC-Timeout transactions immediately as they don't meet the
2891                                         // current locktime requirements on-chain. We will broadcast them in
2892                                         // `block_confirmed` when `should_broadcast_holder_commitment_txn` returns true.
2893                                         // Note that we add + 1 as transactions are broadcastable when they can be
2894                                         // confirmed in the next block.
2895                                         continue;
2896                                 } else { None };
2897                                 if let Some(htlc_tx) = self.onchain_tx_handler.get_fully_signed_htlc_tx(
2898                                         &::bitcoin::OutPoint { txid, vout }, &preimage) {
2899                                         holder_transactions.push(htlc_tx);
2900                                 }
2901                         }
2902                 }
2903                 // 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.
2904                 // The data will be re-generated and tracked in check_spend_holder_transaction if we get a confirmation.
2905                 holder_transactions
2906         }
2907
2908         #[cfg(any(test,feature = "unsafe_revoked_tx_signing"))]
2909         /// Note that this includes possibly-locktimed-in-the-future transactions!
2910         fn unsafe_get_latest_holder_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
2911                 log_debug!(logger, "Getting signed copy of latest holder commitment transaction!");
2912                 let commitment_tx = self.onchain_tx_handler.get_fully_signed_copy_holder_tx(&self.funding_redeemscript);
2913                 let txid = commitment_tx.txid();
2914                 let mut holder_transactions = vec![commitment_tx];
2915                 // When anchor outputs are present, the HTLC transactions are only final once the commitment
2916                 // transaction confirms due to the CSV 1 encumberance.
2917                 if self.onchain_tx_handler.opt_anchors() {
2918                         return holder_transactions;
2919                 }
2920                 for htlc in self.current_holder_commitment_tx.htlc_outputs.iter() {
2921                         if let Some(vout) = htlc.0.transaction_output_index {
2922                                 let preimage = if !htlc.0.offered {
2923                                         if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
2924                                                 // We can't build an HTLC-Success transaction without the preimage
2925                                                 continue;
2926                                         }
2927                                 } else { None };
2928                                 if let Some(htlc_tx) = self.onchain_tx_handler.unsafe_get_fully_signed_htlc_tx(
2929                                         &::bitcoin::OutPoint { txid, vout }, &preimage) {
2930                                         holder_transactions.push(htlc_tx);
2931                                 }
2932                         }
2933                 }
2934                 holder_transactions
2935         }
2936
2937         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>
2938                 where B::Target: BroadcasterInterface,
2939                       F::Target: FeeEstimator,
2940                                         L::Target: Logger,
2941         {
2942                 let block_hash = header.block_hash();
2943                 self.best_block = BestBlock::new(block_hash, height);
2944
2945                 let bounded_fee_estimator = LowerBoundedFeeEstimator::new(fee_estimator);
2946                 self.transactions_confirmed(header, txdata, height, broadcaster, &bounded_fee_estimator, logger)
2947         }
2948
2949         fn best_block_updated<B: Deref, F: Deref, L: Deref>(
2950                 &mut self,
2951                 header: &BlockHeader,
2952                 height: u32,
2953                 broadcaster: B,
2954                 fee_estimator: &LowerBoundedFeeEstimator<F>,
2955                 logger: L,
2956         ) -> Vec<TransactionOutputs>
2957         where
2958                 B::Target: BroadcasterInterface,
2959                 F::Target: FeeEstimator,
2960                 L::Target: Logger,
2961         {
2962                 let block_hash = header.block_hash();
2963
2964                 if height > self.best_block.height() {
2965                         self.best_block = BestBlock::new(block_hash, height);
2966                         self.block_confirmed(height, block_hash, vec![], vec![], vec![], &broadcaster, &fee_estimator, &logger)
2967                 } else if block_hash != self.best_block.block_hash() {
2968                         self.best_block = BestBlock::new(block_hash, height);
2969                         self.onchain_events_awaiting_threshold_conf.retain(|ref entry| entry.height <= height);
2970                         self.onchain_tx_handler.block_disconnected(height + 1, broadcaster, fee_estimator, logger);
2971                         Vec::new()
2972                 } else { Vec::new() }
2973         }
2974
2975         fn transactions_confirmed<B: Deref, F: Deref, L: Deref>(
2976                 &mut self,
2977                 header: &BlockHeader,
2978                 txdata: &TransactionData,
2979                 height: u32,
2980                 broadcaster: B,
2981                 fee_estimator: &LowerBoundedFeeEstimator<F>,
2982                 logger: L,
2983         ) -> Vec<TransactionOutputs>
2984         where
2985                 B::Target: BroadcasterInterface,
2986                 F::Target: FeeEstimator,
2987                 L::Target: Logger,
2988         {
2989                 let txn_matched = self.filter_block(txdata);
2990                 for tx in &txn_matched {
2991                         let mut output_val = 0;
2992                         for out in tx.output.iter() {
2993                                 if out.value > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
2994                                 output_val += out.value;
2995                                 if output_val > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
2996                         }
2997                 }
2998
2999                 let block_hash = header.block_hash();
3000
3001                 let mut watch_outputs = Vec::new();
3002                 let mut claimable_outpoints = Vec::new();
3003                 'tx_iter: for tx in &txn_matched {
3004                         let txid = tx.txid();
3005                         // If a transaction has already been confirmed, ensure we don't bother processing it duplicatively.
3006                         if Some(txid) == self.funding_spend_confirmed {
3007                                 log_debug!(logger, "Skipping redundant processing of funding-spend tx {} as it was previously confirmed", txid);
3008                                 continue 'tx_iter;
3009                         }
3010                         for ev in self.onchain_events_awaiting_threshold_conf.iter() {
3011                                 if ev.txid == txid {
3012                                         if let Some(conf_hash) = ev.block_hash {
3013                                                 assert_eq!(header.block_hash(), conf_hash,
3014                                                         "Transaction {} was already confirmed and is being re-confirmed in a different block.\n\
3015                                                         This indicates a severe bug in the transaction connection logic - a reorg should have been processed first!", ev.txid);
3016                                         }
3017                                         log_debug!(logger, "Skipping redundant processing of confirming tx {} as it was previously confirmed", txid);
3018                                         continue 'tx_iter;
3019                                 }
3020                         }
3021                         for htlc in self.htlcs_resolved_on_chain.iter() {
3022                                 if Some(txid) == htlc.resolving_txid {
3023                                         log_debug!(logger, "Skipping redundant processing of HTLC resolution tx {} as it was previously confirmed", txid);
3024                                         continue 'tx_iter;
3025                                 }
3026                         }
3027                         for spendable_txid in self.spendable_txids_confirmed.iter() {
3028                                 if txid == *spendable_txid {
3029                                         log_debug!(logger, "Skipping redundant processing of spendable tx {} as it was previously confirmed", txid);
3030                                         continue 'tx_iter;
3031                                 }
3032                         }
3033
3034                         if tx.input.len() == 1 {
3035                                 // Assuming our keys were not leaked (in which case we're screwed no matter what),
3036                                 // commitment transactions and HTLC transactions will all only ever have one input
3037                                 // (except for HTLC transactions for channels with anchor outputs), which is an easy
3038                                 // way to filter out any potential non-matching txn for lazy filters.
3039                                 let prevout = &tx.input[0].previous_output;
3040                                 if prevout.txid == self.funding_info.0.txid && prevout.vout == self.funding_info.0.index as u32 {
3041                                         let mut balance_spendable_csv = None;
3042                                         log_info!(logger, "Channel {} closed by funding output spend in txid {}.",
3043                                                 log_bytes!(self.funding_info.0.to_channel_id()), txid);
3044                                         self.funding_spend_seen = true;
3045                                         let mut commitment_tx_to_counterparty_output = None;
3046                                         if (tx.input[0].sequence.0 >> 8*3) as u8 == 0x80 && (tx.lock_time.0 >> 8*3) as u8 == 0x20 {
3047                                                 let (mut new_outpoints, new_outputs, counterparty_output_idx_sats) =
3048                                                         self.check_spend_counterparty_transaction(&tx, height, &block_hash, &logger);
3049                                                 commitment_tx_to_counterparty_output = counterparty_output_idx_sats;
3050                                                 if !new_outputs.1.is_empty() {
3051                                                         watch_outputs.push(new_outputs);
3052                                                 }
3053                                                 claimable_outpoints.append(&mut new_outpoints);
3054                                                 if new_outpoints.is_empty() {
3055                                                         if let Some((mut new_outpoints, new_outputs)) = self.check_spend_holder_transaction(&tx, height, &block_hash, &logger) {
3056                                                                 debug_assert!(commitment_tx_to_counterparty_output.is_none(),
3057                                                                         "A commitment transaction matched as both a counterparty and local commitment tx?");
3058                                                                 if !new_outputs.1.is_empty() {
3059                                                                         watch_outputs.push(new_outputs);
3060                                                                 }
3061                                                                 claimable_outpoints.append(&mut new_outpoints);
3062                                                                 balance_spendable_csv = Some(self.on_holder_tx_csv);
3063                                                         }
3064                                                 }
3065                                         }
3066                                         self.onchain_events_awaiting_threshold_conf.push(OnchainEventEntry {
3067                                                 txid,
3068                                                 transaction: Some((*tx).clone()),
3069                                                 height,
3070                                                 block_hash: Some(block_hash),
3071                                                 event: OnchainEvent::FundingSpendConfirmation {
3072                                                         on_local_output_csv: balance_spendable_csv,
3073                                                         commitment_tx_to_counterparty_output,
3074                                                 },
3075                                         });
3076                                 }
3077                         }
3078                         if tx.input.len() >= 1 {
3079                                 // While all commitment transactions have one input, HTLC transactions may have more
3080                                 // if the HTLC was present in an anchor channel. HTLCs can also be resolved in a few
3081                                 // other ways which can have more than one output.
3082                                 for tx_input in &tx.input {
3083                                         let commitment_txid = tx_input.previous_output.txid;
3084                                         if let Some(&commitment_number) = self.counterparty_commitment_txn_on_chain.get(&commitment_txid) {
3085                                                 let (mut new_outpoints, new_outputs_option) = self.check_spend_counterparty_htlc(
3086                                                         &tx, commitment_number, &commitment_txid, height, &logger
3087                                                 );
3088                                                 claimable_outpoints.append(&mut new_outpoints);
3089                                                 if let Some(new_outputs) = new_outputs_option {
3090                                                         watch_outputs.push(new_outputs);
3091                                                 }
3092                                                 // Since there may be multiple HTLCs for this channel (all spending the
3093                                                 // same commitment tx) being claimed by the counterparty within the same
3094                                                 // transaction, and `check_spend_counterparty_htlc` already checks all the
3095                                                 // ones relevant to this channel, we can safely break from our loop.
3096                                                 break;
3097                                         }
3098                                 }
3099                                 self.is_resolving_htlc_output(&tx, height, &block_hash, &logger);
3100
3101                                 self.is_paying_spendable_output(&tx, height, &block_hash, &logger);
3102                         }
3103                 }
3104
3105                 if height > self.best_block.height() {
3106                         self.best_block = BestBlock::new(block_hash, height);
3107                 }
3108
3109                 self.block_confirmed(height, block_hash, txn_matched, watch_outputs, claimable_outpoints, &broadcaster, &fee_estimator, &logger)
3110         }
3111
3112         /// Update state for new block(s)/transaction(s) confirmed. Note that the caller must update
3113         /// `self.best_block` before calling if a new best blockchain tip is available. More
3114         /// concretely, `self.best_block` must never be at a lower height than `conf_height`, avoiding
3115         /// complexity especially in
3116         /// `OnchainTx::update_claims_view_from_requests`/`OnchainTx::update_claims_view_from_matched_txn`.
3117         ///
3118         /// `conf_height` should be set to the height at which any new transaction(s)/block(s) were
3119         /// confirmed at, even if it is not the current best height.
3120         fn block_confirmed<B: Deref, F: Deref, L: Deref>(
3121                 &mut self,
3122                 conf_height: u32,
3123                 conf_hash: BlockHash,
3124                 txn_matched: Vec<&Transaction>,
3125                 mut watch_outputs: Vec<TransactionOutputs>,
3126                 mut claimable_outpoints: Vec<PackageTemplate>,
3127                 broadcaster: &B,
3128                 fee_estimator: &LowerBoundedFeeEstimator<F>,
3129                 logger: &L,
3130         ) -> Vec<TransactionOutputs>
3131         where
3132                 B::Target: BroadcasterInterface,
3133                 F::Target: FeeEstimator,
3134                 L::Target: Logger,
3135         {
3136                 log_trace!(logger, "Processing {} matched transactions for block at height {}.", txn_matched.len(), conf_height);
3137                 debug_assert!(self.best_block.height() >= conf_height);
3138
3139                 let should_broadcast = self.should_broadcast_holder_commitment_txn(logger);
3140                 if should_broadcast {
3141                         let funding_outp = HolderFundingOutput::build(self.funding_redeemscript.clone(), self.channel_value_satoshis, self.onchain_tx_handler.opt_anchors());
3142                         let commitment_package = PackageTemplate::build_package(self.funding_info.0.txid.clone(), self.funding_info.0.index as u32, PackageSolvingData::HolderFundingOutput(funding_outp), self.best_block.height(), false, self.best_block.height());
3143                         claimable_outpoints.push(commitment_package);
3144                         self.pending_monitor_events.push(MonitorEvent::CommitmentTxConfirmed(self.funding_info.0));
3145                         let commitment_tx = self.onchain_tx_handler.get_fully_signed_holder_tx(&self.funding_redeemscript);
3146                         self.holder_tx_signed = true;
3147                         // We can't broadcast our HTLC transactions while the commitment transaction is
3148                         // unconfirmed. We'll delay doing so until we detect the confirmed commitment in
3149                         // `transactions_confirmed`.
3150                         if !self.onchain_tx_handler.opt_anchors() {
3151                                 // Because we're broadcasting a commitment transaction, we should construct the package
3152                                 // assuming it gets confirmed in the next block. Sadly, we have code which considers
3153                                 // "not yet confirmed" things as discardable, so we cannot do that here.
3154                                 let (mut new_outpoints, _) = self.get_broadcasted_holder_claims(&self.current_holder_commitment_tx, self.best_block.height());
3155                                 let new_outputs = self.get_broadcasted_holder_watch_outputs(&self.current_holder_commitment_tx, &commitment_tx);
3156                                 if !new_outputs.is_empty() {
3157                                         watch_outputs.push((self.current_holder_commitment_tx.txid.clone(), new_outputs));
3158                                 }
3159                                 claimable_outpoints.append(&mut new_outpoints);
3160                         }
3161                 }
3162
3163                 // Find which on-chain events have reached their confirmation threshold.
3164                 let onchain_events_awaiting_threshold_conf =
3165                         self.onchain_events_awaiting_threshold_conf.drain(..).collect::<Vec<_>>();
3166                 let mut onchain_events_reaching_threshold_conf = Vec::new();
3167                 for entry in onchain_events_awaiting_threshold_conf {
3168                         if entry.has_reached_confirmation_threshold(&self.best_block) {
3169                                 onchain_events_reaching_threshold_conf.push(entry);
3170                         } else {
3171                                 self.onchain_events_awaiting_threshold_conf.push(entry);
3172                         }
3173                 }
3174
3175                 // Used to check for duplicate HTLC resolutions.
3176                 #[cfg(debug_assertions)]
3177                 let unmatured_htlcs: Vec<_> = self.onchain_events_awaiting_threshold_conf
3178                         .iter()
3179                         .filter_map(|entry| match &entry.event {
3180                                 OnchainEvent::HTLCUpdate { source, .. } => Some(source),
3181                                 _ => None,
3182                         })
3183                         .collect();
3184                 #[cfg(debug_assertions)]
3185                 let mut matured_htlcs = Vec::new();
3186
3187                 // Produce actionable events from on-chain events having reached their threshold.
3188                 for entry in onchain_events_reaching_threshold_conf.drain(..) {
3189                         match entry.event {
3190                                 OnchainEvent::HTLCUpdate { ref source, payment_hash, htlc_value_satoshis, commitment_tx_output_idx } => {
3191                                         // Check for duplicate HTLC resolutions.
3192                                         #[cfg(debug_assertions)]
3193                                         {
3194                                                 debug_assert!(
3195                                                         unmatured_htlcs.iter().find(|&htlc| htlc == &source).is_none(),
3196                                                         "An unmature HTLC transaction conflicts with a maturing one; failed to \
3197                                                          call either transaction_unconfirmed for the conflicting transaction \
3198                                                          or block_disconnected for a block containing it.");
3199                                                 debug_assert!(
3200                                                         matured_htlcs.iter().find(|&htlc| htlc == source).is_none(),
3201                                                         "A matured HTLC transaction conflicts with a maturing one; failed to \
3202                                                          call either transaction_unconfirmed for the conflicting transaction \
3203                                                          or block_disconnected for a block containing it.");
3204                                                 matured_htlcs.push(source.clone());
3205                                         }
3206
3207                                         log_debug!(logger, "HTLC {} failure update in {} has got enough confirmations to be passed upstream",
3208                                                 log_bytes!(payment_hash.0), entry.txid);
3209                                         self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
3210                                                 payment_hash,
3211                                                 payment_preimage: None,
3212                                                 source: source.clone(),
3213                                                 htlc_value_satoshis,
3214                                         }));
3215                                         self.htlcs_resolved_on_chain.push(IrrevocablyResolvedHTLC {
3216                                                 commitment_tx_output_idx,
3217                                                 resolving_txid: Some(entry.txid),
3218                                                 resolving_tx: entry.transaction,
3219                                                 payment_preimage: None,
3220                                         });
3221                                 },
3222                                 OnchainEvent::MaturingOutput { descriptor } => {
3223                                         log_debug!(logger, "Descriptor {} has got enough confirmations to be passed upstream", log_spendable!(descriptor));
3224                                         self.pending_events.push(Event::SpendableOutputs {
3225                                                 outputs: vec![descriptor]
3226                                         });
3227                                         self.spendable_txids_confirmed.push(entry.txid);
3228                                 },
3229                                 OnchainEvent::HTLCSpendConfirmation { commitment_tx_output_idx, preimage, .. } => {
3230                                         self.htlcs_resolved_on_chain.push(IrrevocablyResolvedHTLC {
3231                                                 commitment_tx_output_idx: Some(commitment_tx_output_idx),
3232                                                 resolving_txid: Some(entry.txid),
3233                                                 resolving_tx: entry.transaction,
3234                                                 payment_preimage: preimage,
3235                                         });
3236                                 },
3237                                 OnchainEvent::FundingSpendConfirmation { commitment_tx_to_counterparty_output, .. } => {
3238                                         self.funding_spend_confirmed = Some(entry.txid);
3239                                         self.confirmed_commitment_tx_counterparty_output = commitment_tx_to_counterparty_output;
3240                                 },
3241                         }
3242                 }
3243
3244                 self.onchain_tx_handler.update_claims_view_from_requests(claimable_outpoints, conf_height, self.best_block.height(), broadcaster, fee_estimator, logger);
3245                 self.onchain_tx_handler.update_claims_view_from_matched_txn(&txn_matched, conf_height, conf_hash, self.best_block.height(), broadcaster, fee_estimator, logger);
3246
3247                 // Determine new outputs to watch by comparing against previously known outputs to watch,
3248                 // updating the latter in the process.
3249                 watch_outputs.retain(|&(ref txid, ref txouts)| {
3250                         let idx_and_scripts = txouts.iter().map(|o| (o.0, o.1.script_pubkey.clone())).collect();
3251                         self.outputs_to_watch.insert(txid.clone(), idx_and_scripts).is_none()
3252                 });
3253                 #[cfg(test)]
3254                 {
3255                         // If we see a transaction for which we registered outputs previously,
3256                         // make sure the registered scriptpubkey at the expected index match
3257                         // the actual transaction output one. We failed this case before #653.
3258                         for tx in &txn_matched {
3259                                 if let Some(outputs) = self.get_outputs_to_watch().get(&tx.txid()) {
3260                                         for idx_and_script in outputs.iter() {
3261                                                 assert!((idx_and_script.0 as usize) < tx.output.len());
3262                                                 assert_eq!(tx.output[idx_and_script.0 as usize].script_pubkey, idx_and_script.1);
3263                                         }
3264                                 }
3265                         }
3266                 }
3267                 watch_outputs
3268         }
3269
3270         pub fn block_disconnected<B: Deref, F: Deref, L: Deref>(&mut self, header: &BlockHeader, height: u32, broadcaster: B, fee_estimator: F, logger: L)
3271                 where B::Target: BroadcasterInterface,
3272                       F::Target: FeeEstimator,
3273                       L::Target: Logger,
3274         {
3275                 log_trace!(logger, "Block {} at height {} disconnected", header.block_hash(), height);
3276
3277                 //We may discard:
3278                 //- htlc update there as failure-trigger tx (revoked commitment tx, non-revoked commitment tx, HTLC-timeout tx) has been disconnected
3279                 //- maturing spendable output has transaction paying us has been disconnected
3280                 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| entry.height < height);
3281
3282                 let bounded_fee_estimator = LowerBoundedFeeEstimator::new(fee_estimator);
3283                 self.onchain_tx_handler.block_disconnected(height, broadcaster, &bounded_fee_estimator, logger);
3284
3285                 self.best_block = BestBlock::new(header.prev_blockhash, height - 1);
3286         }
3287
3288         fn transaction_unconfirmed<B: Deref, F: Deref, L: Deref>(
3289                 &mut self,
3290                 txid: &Txid,
3291                 broadcaster: B,
3292                 fee_estimator: &LowerBoundedFeeEstimator<F>,
3293                 logger: L,
3294         ) where
3295                 B::Target: BroadcasterInterface,
3296                 F::Target: FeeEstimator,
3297                 L::Target: Logger,
3298         {
3299                 let mut removed_height = None;
3300                 for entry in self.onchain_events_awaiting_threshold_conf.iter() {
3301                         if entry.txid == *txid {
3302                                 removed_height = Some(entry.height);
3303                                 break;
3304                         }
3305                 }
3306
3307                 if let Some(removed_height) = removed_height {
3308                         log_info!(logger, "transaction_unconfirmed of txid {} implies height {} was reorg'd out", txid, removed_height);
3309                         self.onchain_events_awaiting_threshold_conf.retain(|ref entry| if entry.height >= removed_height {
3310                                 log_info!(logger, "Transaction {} reorg'd out", entry.txid);
3311                                 false
3312                         } else { true });
3313                 }
3314
3315                 debug_assert!(!self.onchain_events_awaiting_threshold_conf.iter().any(|ref entry| entry.txid == *txid));
3316
3317                 self.onchain_tx_handler.transaction_unconfirmed(txid, broadcaster, fee_estimator, logger);
3318         }
3319
3320         /// Filters a block's `txdata` for transactions spending watched outputs or for any child
3321         /// transactions thereof.
3322         fn filter_block<'a>(&self, txdata: &TransactionData<'a>) -> Vec<&'a Transaction> {
3323                 let mut matched_txn = HashSet::new();
3324                 txdata.iter().filter(|&&(_, tx)| {
3325                         let mut matches = self.spends_watched_output(tx);
3326                         for input in tx.input.iter() {
3327                                 if matches { break; }
3328                                 if matched_txn.contains(&input.previous_output.txid) {
3329                                         matches = true;
3330                                 }
3331                         }
3332                         if matches {
3333                                 matched_txn.insert(tx.txid());
3334                         }
3335                         matches
3336                 }).map(|(_, tx)| *tx).collect()
3337         }
3338
3339         /// Checks if a given transaction spends any watched outputs.
3340         fn spends_watched_output(&self, tx: &Transaction) -> bool {
3341                 for input in tx.input.iter() {
3342                         if let Some(outputs) = self.get_outputs_to_watch().get(&input.previous_output.txid) {
3343                                 for (idx, _script_pubkey) in outputs.iter() {
3344                                         if *idx == input.previous_output.vout {
3345                                                 #[cfg(test)]
3346                                                 {
3347                                                         // If the expected script is a known type, check that the witness
3348                                                         // appears to be spending the correct type (ie that the match would
3349                                                         // actually succeed in BIP 158/159-style filters).
3350                                                         if _script_pubkey.is_v0_p2wsh() {
3351                                                                 if input.witness.last().unwrap().to_vec() == deliberately_bogus_accepted_htlc_witness_program() {
3352                                                                         // In at least one test we use a deliberately bogus witness
3353                                                                         // script which hit an old panic. Thus, we check for that here
3354                                                                         // and avoid the assert if its the expected bogus script.
3355                                                                         return true;
3356                                                                 }
3357
3358                                                                 assert_eq!(&bitcoin::Address::p2wsh(&Script::from(input.witness.last().unwrap().to_vec()), bitcoin::Network::Bitcoin).script_pubkey(), _script_pubkey);
3359                                                         } else if _script_pubkey.is_v0_p2wpkh() {
3360                                                                 assert_eq!(&bitcoin::Address::p2wpkh(&bitcoin::PublicKey::from_slice(&input.witness.last().unwrap()).unwrap(), bitcoin::Network::Bitcoin).unwrap().script_pubkey(), _script_pubkey);
3361                                                         } else { panic!(); }
3362                                                 }
3363                                                 return true;
3364                                         }
3365                                 }
3366                         }
3367                 }
3368
3369                 false
3370         }
3371
3372         fn should_broadcast_holder_commitment_txn<L: Deref>(&self, logger: &L) -> bool where L::Target: Logger {
3373                 // There's no need to broadcast our commitment transaction if we've seen one confirmed (even
3374                 // with 1 confirmation) as it'll be rejected as duplicate/conflicting.
3375                 if self.funding_spend_confirmed.is_some() ||
3376                         self.onchain_events_awaiting_threshold_conf.iter().find(|event| match event.event {
3377                                 OnchainEvent::FundingSpendConfirmation { .. } => true,
3378                                 _ => false,
3379                         }).is_some()
3380                 {
3381                         return false;
3382                 }
3383                 // We need to consider all HTLCs which are:
3384                 //  * in any unrevoked counterparty commitment transaction, as they could broadcast said
3385                 //    transactions and we'd end up in a race, or
3386                 //  * are in our latest holder commitment transaction, as this is the thing we will
3387                 //    broadcast if we go on-chain.
3388                 // Note that we consider HTLCs which were below dust threshold here - while they don't
3389                 // strictly imply that we need to fail the channel, we need to go ahead and fail them back
3390                 // to the source, and if we don't fail the channel we will have to ensure that the next
3391                 // updates that peer sends us are update_fails, failing the channel if not. It's probably
3392                 // easier to just fail the channel as this case should be rare enough anyway.
3393                 let height = self.best_block.height();
3394                 macro_rules! scan_commitment {
3395                         ($htlcs: expr, $holder_tx: expr) => {
3396                                 for ref htlc in $htlcs {
3397                                         // For inbound HTLCs which we know the preimage for, we have to ensure we hit the
3398                                         // chain with enough room to claim the HTLC without our counterparty being able to
3399                                         // time out the HTLC first.
3400                                         // For outbound HTLCs which our counterparty hasn't failed/claimed, our primary
3401                                         // concern is being able to claim the corresponding inbound HTLC (on another
3402                                         // channel) before it expires. In fact, we don't even really care if our
3403                                         // counterparty here claims such an outbound HTLC after it expired as long as we
3404                                         // can still claim the corresponding HTLC. Thus, to avoid needlessly hitting the
3405                                         // chain when our counterparty is waiting for expiration to off-chain fail an HTLC
3406                                         // we give ourselves a few blocks of headroom after expiration before going
3407                                         // on-chain for an expired HTLC.
3408                                         // Note that, to avoid a potential attack whereby a node delays claiming an HTLC
3409                                         // from us until we've reached the point where we go on-chain with the
3410                                         // corresponding inbound HTLC, we must ensure that outbound HTLCs go on chain at
3411                                         // least CLTV_CLAIM_BUFFER blocks prior to the inbound HTLC.
3412                                         //  aka outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS == height - CLTV_CLAIM_BUFFER
3413                                         //      inbound_cltv == height + CLTV_CLAIM_BUFFER
3414                                         //      outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS + CLTV_CLAIM_BUFFER <= inbound_cltv - CLTV_CLAIM_BUFFER
3415                                         //      LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= inbound_cltv - outbound_cltv
3416                                         //      CLTV_EXPIRY_DELTA <= inbound_cltv - outbound_cltv (by check in ChannelManager::decode_update_add_htlc_onion)
3417                                         //      LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= CLTV_EXPIRY_DELTA
3418                                         //  The final, above, condition is checked for statically in channelmanager
3419                                         //  with CHECK_CLTV_EXPIRY_SANITY_2.
3420                                         let htlc_outbound = $holder_tx == htlc.offered;
3421                                         if ( htlc_outbound && htlc.cltv_expiry + LATENCY_GRACE_PERIOD_BLOCKS <= height) ||
3422                                            (!htlc_outbound && htlc.cltv_expiry <= height + CLTV_CLAIM_BUFFER && self.payment_preimages.contains_key(&htlc.payment_hash)) {
3423                                                 log_info!(logger, "Force-closing channel due to {} HTLC timeout, HTLC expiry is {}", if htlc_outbound { "outbound" } else { "inbound "}, htlc.cltv_expiry);
3424                                                 return true;
3425                                         }
3426                                 }
3427                         }
3428                 }
3429
3430                 scan_commitment!(self.current_holder_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, _)| a), true);
3431
3432                 if let Some(ref txid) = self.current_counterparty_commitment_txid {
3433                         if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(txid) {
3434                                 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
3435                         }
3436                 }
3437                 if let Some(ref txid) = self.prev_counterparty_commitment_txid {
3438                         if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(txid) {
3439                                 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
3440                         }
3441                 }
3442
3443                 false
3444         }
3445
3446         /// Check if any transaction broadcasted is resolving HTLC output by a success or timeout on a holder
3447         /// or counterparty commitment tx, if so send back the source, preimage if found and payment_hash of resolved HTLC
3448         fn is_resolving_htlc_output<L: Deref>(&mut self, tx: &Transaction, height: u32, block_hash: &BlockHash, logger: &L) where L::Target: Logger {
3449                 'outer_loop: for input in &tx.input {
3450                         let mut payment_data = None;
3451                         let htlc_claim = HTLCClaim::from_witness(&input.witness);
3452                         let revocation_sig_claim = htlc_claim == Some(HTLCClaim::Revocation);
3453                         let accepted_preimage_claim = htlc_claim == Some(HTLCClaim::AcceptedPreimage);
3454                         #[cfg(not(fuzzing))]
3455                         let accepted_timeout_claim = htlc_claim == Some(HTLCClaim::AcceptedTimeout);
3456                         let offered_preimage_claim = htlc_claim == Some(HTLCClaim::OfferedPreimage);
3457                         #[cfg(not(fuzzing))]
3458                         let offered_timeout_claim = htlc_claim == Some(HTLCClaim::OfferedTimeout);
3459
3460                         let mut payment_preimage = PaymentPreimage([0; 32]);
3461                         if offered_preimage_claim || accepted_preimage_claim {
3462                                 payment_preimage.0.copy_from_slice(input.witness.second_to_last().unwrap());
3463                         }
3464
3465                         macro_rules! log_claim {
3466                                 ($tx_info: expr, $holder_tx: expr, $htlc: expr, $source_avail: expr) => {
3467                                         let outbound_htlc = $holder_tx == $htlc.offered;
3468                                         // HTLCs must either be claimed by a matching script type or through the
3469                                         // revocation path:
3470                                         #[cfg(not(fuzzing))] // Note that the fuzzer is not bound by pesky things like "signatures"
3471                                         debug_assert!(!$htlc.offered || offered_preimage_claim || offered_timeout_claim || revocation_sig_claim);
3472                                         #[cfg(not(fuzzing))] // Note that the fuzzer is not bound by pesky things like "signatures"
3473                                         debug_assert!($htlc.offered || accepted_preimage_claim || accepted_timeout_claim || revocation_sig_claim);
3474                                         // Further, only exactly one of the possible spend paths should have been
3475                                         // matched by any HTLC spend:
3476                                         #[cfg(not(fuzzing))] // Note that the fuzzer is not bound by pesky things like "signatures"
3477                                         debug_assert_eq!(accepted_preimage_claim as u8 + accepted_timeout_claim as u8 +
3478                                                          offered_preimage_claim as u8 + offered_timeout_claim as u8 +
3479                                                          revocation_sig_claim as u8, 1);
3480                                         if ($holder_tx && revocation_sig_claim) ||
3481                                                         (outbound_htlc && !$source_avail && (accepted_preimage_claim || offered_preimage_claim)) {
3482                                                 log_error!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}!",
3483                                                         $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
3484                                                         if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
3485                                                         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" });
3486                                         } else {
3487                                                 log_info!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}",
3488                                                         $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
3489                                                         if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
3490                                                         if revocation_sig_claim { "revocation sig" } else if accepted_preimage_claim || offered_preimage_claim { "preimage" } else { "timeout" });
3491                                         }
3492                                 }
3493                         }
3494
3495                         macro_rules! check_htlc_valid_counterparty {
3496                                 ($counterparty_txid: expr, $htlc_output: expr) => {
3497                                         if let Some(txid) = $counterparty_txid {
3498                                                 for &(ref pending_htlc, ref pending_source) in self.counterparty_claimable_outpoints.get(&txid).unwrap() {
3499                                                         if pending_htlc.payment_hash == $htlc_output.payment_hash && pending_htlc.amount_msat == $htlc_output.amount_msat {
3500                                                                 if let &Some(ref source) = pending_source {
3501                                                                         log_claim!("revoked counterparty commitment tx", false, pending_htlc, true);
3502                                                                         payment_data = Some(((**source).clone(), $htlc_output.payment_hash, $htlc_output.amount_msat));
3503                                                                         break;
3504                                                                 }
3505                                                         }
3506                                                 }
3507                                         }
3508                                 }
3509                         }
3510
3511                         macro_rules! scan_commitment {
3512                                 ($htlcs: expr, $tx_info: expr, $holder_tx: expr) => {
3513                                         for (ref htlc_output, source_option) in $htlcs {
3514                                                 if Some(input.previous_output.vout) == htlc_output.transaction_output_index {
3515                                                         if let Some(ref source) = source_option {
3516                                                                 log_claim!($tx_info, $holder_tx, htlc_output, true);
3517                                                                 // We have a resolution of an HTLC either from one of our latest
3518                                                                 // holder commitment transactions or an unrevoked counterparty commitment
3519                                                                 // transaction. This implies we either learned a preimage, the HTLC
3520                                                                 // has timed out, or we screwed up. In any case, we should now
3521                                                                 // resolve the source HTLC with the original sender.
3522                                                                 payment_data = Some(((*source).clone(), htlc_output.payment_hash, htlc_output.amount_msat));
3523                                                         } else if !$holder_tx {
3524                                                                 check_htlc_valid_counterparty!(self.current_counterparty_commitment_txid, htlc_output);
3525                                                                 if payment_data.is_none() {
3526                                                                         check_htlc_valid_counterparty!(self.prev_counterparty_commitment_txid, htlc_output);
3527                                                                 }
3528                                                         }
3529                                                         if payment_data.is_none() {
3530                                                                 log_claim!($tx_info, $holder_tx, htlc_output, false);
3531                                                                 let outbound_htlc = $holder_tx == htlc_output.offered;
3532                                                                 self.onchain_events_awaiting_threshold_conf.push(OnchainEventEntry {
3533                                                                         txid: tx.txid(), height, block_hash: Some(*block_hash), transaction: Some(tx.clone()),
3534                                                                         event: OnchainEvent::HTLCSpendConfirmation {
3535                                                                                 commitment_tx_output_idx: input.previous_output.vout,
3536                                                                                 preimage: if accepted_preimage_claim || offered_preimage_claim {
3537                                                                                         Some(payment_preimage) } else { None },
3538                                                                                 // If this is a payment to us (ie !outbound_htlc), wait for
3539                                                                                 // the CSV delay before dropping the HTLC from claimable
3540                                                                                 // balance if the claim was an HTLC-Success transaction (ie
3541                                                                                 // accepted_preimage_claim).
3542                                                                                 on_to_local_output_csv: if accepted_preimage_claim && !outbound_htlc {
3543                                                                                         Some(self.on_holder_tx_csv) } else { None },
3544                                                                         },
3545                                                                 });
3546                                                                 continue 'outer_loop;
3547                                                         }
3548                                                 }
3549                                         }
3550                                 }
3551                         }
3552
3553                         if input.previous_output.txid == self.current_holder_commitment_tx.txid {
3554                                 scan_commitment!(self.current_holder_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
3555                                         "our latest holder commitment tx", true);
3556                         }
3557                         if let Some(ref prev_holder_signed_commitment_tx) = self.prev_holder_signed_commitment_tx {
3558                                 if input.previous_output.txid == prev_holder_signed_commitment_tx.txid {
3559                                         scan_commitment!(prev_holder_signed_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
3560                                                 "our previous holder commitment tx", true);
3561                                 }
3562                         }
3563                         if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(&input.previous_output.txid) {
3564                                 scan_commitment!(htlc_outputs.iter().map(|&(ref a, ref b)| (a, (b.as_ref().clone()).map(|boxed| &**boxed))),
3565                                         "counterparty commitment tx", false);
3566                         }
3567
3568                         // Check that scan_commitment, above, decided there is some source worth relaying an
3569                         // HTLC resolution backwards to and figure out whether we learned a preimage from it.
3570                         if let Some((source, payment_hash, amount_msat)) = payment_data {
3571                                 if accepted_preimage_claim {
3572                                         if !self.pending_monitor_events.iter().any(
3573                                                 |update| if let &MonitorEvent::HTLCEvent(ref upd) = update { upd.source == source } else { false }) {
3574                                                 self.onchain_events_awaiting_threshold_conf.push(OnchainEventEntry {
3575                                                         txid: tx.txid(),
3576                                                         height,
3577                                                         block_hash: Some(*block_hash),
3578                                                         transaction: Some(tx.clone()),
3579                                                         event: OnchainEvent::HTLCSpendConfirmation {
3580                                                                 commitment_tx_output_idx: input.previous_output.vout,
3581                                                                 preimage: Some(payment_preimage),
3582                                                                 on_to_local_output_csv: None,
3583                                                         },
3584                                                 });
3585                                                 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
3586                                                         source,
3587                                                         payment_preimage: Some(payment_preimage),
3588                                                         payment_hash,
3589                                                         htlc_value_satoshis: Some(amount_msat / 1000),
3590                                                 }));
3591                                         }
3592                                 } else if offered_preimage_claim {
3593                                         if !self.pending_monitor_events.iter().any(
3594                                                 |update| if let &MonitorEvent::HTLCEvent(ref upd) = update {
3595                                                         upd.source == source
3596                                                 } else { false }) {
3597                                                 self.onchain_events_awaiting_threshold_conf.push(OnchainEventEntry {
3598                                                         txid: tx.txid(),
3599                                                         transaction: Some(tx.clone()),
3600                                                         height,
3601                                                         block_hash: Some(*block_hash),
3602                                                         event: OnchainEvent::HTLCSpendConfirmation {
3603                                                                 commitment_tx_output_idx: input.previous_output.vout,
3604                                                                 preimage: Some(payment_preimage),
3605                                                                 on_to_local_output_csv: None,
3606                                                         },
3607                                                 });
3608                                                 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
3609                                                         source,
3610                                                         payment_preimage: Some(payment_preimage),
3611                                                         payment_hash,
3612                                                         htlc_value_satoshis: Some(amount_msat / 1000),
3613                                                 }));
3614                                         }
3615                                 } else {
3616                                         self.onchain_events_awaiting_threshold_conf.retain(|ref entry| {
3617                                                 if entry.height != height { return true; }
3618                                                 match entry.event {
3619                                                         OnchainEvent::HTLCUpdate { source: ref htlc_source, .. } => {
3620                                                                 *htlc_source != source
3621                                                         },
3622                                                         _ => true,
3623                                                 }
3624                                         });
3625                                         let entry = OnchainEventEntry {
3626                                                 txid: tx.txid(),
3627                                                 transaction: Some(tx.clone()),
3628                                                 height,
3629                                                 block_hash: Some(*block_hash),
3630                                                 event: OnchainEvent::HTLCUpdate {
3631                                                         source, payment_hash,
3632                                                         htlc_value_satoshis: Some(amount_msat / 1000),
3633                                                         commitment_tx_output_idx: Some(input.previous_output.vout),
3634                                                 },
3635                                         };
3636                                         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());
3637                                         self.onchain_events_awaiting_threshold_conf.push(entry);
3638                                 }
3639                         }
3640                 }
3641         }
3642
3643         /// Check if any transaction broadcasted is paying fund back to some address we can assume to own
3644         fn is_paying_spendable_output<L: Deref>(&mut self, tx: &Transaction, height: u32, block_hash: &BlockHash, logger: &L) where L::Target: Logger {
3645                 let mut spendable_output = None;
3646                 for (i, outp) in tx.output.iter().enumerate() { // There is max one spendable output for any channel tx, including ones generated by us
3647                         if i > ::core::u16::MAX as usize {
3648                                 // While it is possible that an output exists on chain which is greater than the
3649                                 // 2^16th output in a given transaction, this is only possible if the output is not
3650                                 // in a lightning transaction and was instead placed there by some third party who
3651                                 // wishes to give us money for no reason.
3652                                 // Namely, any lightning transactions which we pre-sign will never have anywhere
3653                                 // near 2^16 outputs both because such transactions must have ~2^16 outputs who's
3654                                 // scripts are not longer than one byte in length and because they are inherently
3655                                 // non-standard due to their size.
3656                                 // Thus, it is completely safe to ignore such outputs, and while it may result in
3657                                 // us ignoring non-lightning fund to us, that is only possible if someone fills
3658                                 // nearly a full block with garbage just to hit this case.
3659                                 continue;
3660                         }
3661                         if outp.script_pubkey == self.destination_script {
3662                                 spendable_output =  Some(SpendableOutputDescriptor::StaticOutput {
3663                                         outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
3664                                         output: outp.clone(),
3665                                 });
3666                                 break;
3667                         }
3668                         if let Some(ref broadcasted_holder_revokable_script) = self.broadcasted_holder_revokable_script {
3669                                 if broadcasted_holder_revokable_script.0 == outp.script_pubkey {
3670                                         spendable_output =  Some(SpendableOutputDescriptor::DelayedPaymentOutput(DelayedPaymentOutputDescriptor {
3671                                                 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
3672                                                 per_commitment_point: broadcasted_holder_revokable_script.1,
3673                                                 to_self_delay: self.on_holder_tx_csv,
3674                                                 output: outp.clone(),
3675                                                 revocation_pubkey: broadcasted_holder_revokable_script.2.clone(),
3676                                                 channel_keys_id: self.channel_keys_id,
3677                                                 channel_value_satoshis: self.channel_value_satoshis,
3678                                         }));
3679                                         break;
3680                                 }
3681                         }
3682                         if self.counterparty_payment_script == outp.script_pubkey {
3683                                 spendable_output = Some(SpendableOutputDescriptor::StaticPaymentOutput(StaticPaymentOutputDescriptor {
3684                                         outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
3685                                         output: outp.clone(),
3686                                         channel_keys_id: self.channel_keys_id,
3687                                         channel_value_satoshis: self.channel_value_satoshis,
3688                                 }));
3689                                 break;
3690                         }
3691                         if self.shutdown_script.as_ref() == Some(&outp.script_pubkey) {
3692                                 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
3693                                         outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
3694                                         output: outp.clone(),
3695                                 });
3696                                 break;
3697                         }
3698                 }
3699                 if let Some(spendable_output) = spendable_output {
3700                         let entry = OnchainEventEntry {
3701                                 txid: tx.txid(),
3702                                 transaction: Some(tx.clone()),
3703                                 height,
3704                                 block_hash: Some(*block_hash),
3705                                 event: OnchainEvent::MaturingOutput { descriptor: spendable_output.clone() },
3706                         };
3707                         log_info!(logger, "Received spendable output {}, spendable at height {}", log_spendable!(spendable_output), entry.confirmation_threshold());
3708                         self.onchain_events_awaiting_threshold_conf.push(entry);
3709                 }
3710         }
3711 }
3712
3713 impl<Signer: WriteableEcdsaChannelSigner, T: Deref, F: Deref, L: Deref> chain::Listen for (ChannelMonitor<Signer>, T, F, L)
3714 where
3715         T::Target: BroadcasterInterface,
3716         F::Target: FeeEstimator,
3717         L::Target: Logger,
3718 {
3719         fn filtered_block_connected(&self, header: &BlockHeader, txdata: &TransactionData, height: u32) {
3720                 self.0.block_connected(header, txdata, height, &*self.1, &*self.2, &*self.3);
3721         }
3722
3723         fn block_disconnected(&self, header: &BlockHeader, height: u32) {
3724                 self.0.block_disconnected(header, height, &*self.1, &*self.2, &*self.3);
3725         }
3726 }
3727
3728 impl<Signer: WriteableEcdsaChannelSigner, M, T: Deref, F: Deref, L: Deref> chain::Confirm for (M, T, F, L)
3729 where
3730         M: Deref<Target = ChannelMonitor<Signer>>,
3731         T::Target: BroadcasterInterface,
3732         F::Target: FeeEstimator,
3733         L::Target: Logger,
3734 {
3735         fn transactions_confirmed(&self, header: &BlockHeader, txdata: &TransactionData, height: u32) {
3736                 self.0.transactions_confirmed(header, txdata, height, &*self.1, &*self.2, &*self.3);
3737         }
3738
3739         fn transaction_unconfirmed(&self, txid: &Txid) {
3740                 self.0.transaction_unconfirmed(txid, &*self.1, &*self.2, &*self.3);
3741         }
3742
3743         fn best_block_updated(&self, header: &BlockHeader, height: u32) {
3744                 self.0.best_block_updated(header, height, &*self.1, &*self.2, &*self.3);
3745         }
3746
3747         fn get_relevant_txids(&self) -> Vec<(Txid, Option<BlockHash>)> {
3748                 self.0.get_relevant_txids()
3749         }
3750 }
3751
3752 const MAX_ALLOC_SIZE: usize = 64*1024;
3753
3754 impl<'a, 'b, ES: EntropySource, SP: SignerProvider> ReadableArgs<(&'a ES, &'b SP)>
3755                 for (BlockHash, ChannelMonitor<SP::Signer>) {
3756         fn read<R: io::Read>(reader: &mut R, args: (&'a ES, &'b SP)) -> Result<Self, DecodeError> {
3757                 macro_rules! unwrap_obj {
3758                         ($key: expr) => {
3759                                 match $key {
3760                                         Ok(res) => res,
3761                                         Err(_) => return Err(DecodeError::InvalidValue),
3762                                 }
3763                         }
3764                 }
3765
3766                 let (entropy_source, signer_provider) = args;
3767
3768                 let _ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
3769
3770                 let latest_update_id: u64 = Readable::read(reader)?;
3771                 let commitment_transaction_number_obscure_factor = <U48 as Readable>::read(reader)?.0;
3772
3773                 let destination_script = Readable::read(reader)?;
3774                 let broadcasted_holder_revokable_script = match <u8 as Readable>::read(reader)? {
3775                         0 => {
3776                                 let revokable_address = Readable::read(reader)?;
3777                                 let per_commitment_point = Readable::read(reader)?;
3778                                 let revokable_script = Readable::read(reader)?;
3779                                 Some((revokable_address, per_commitment_point, revokable_script))
3780                         },
3781                         1 => { None },
3782                         _ => return Err(DecodeError::InvalidValue),
3783                 };
3784                 let counterparty_payment_script = Readable::read(reader)?;
3785                 let shutdown_script = {
3786                         let script = <Script as Readable>::read(reader)?;
3787                         if script.is_empty() { None } else { Some(script) }
3788                 };
3789
3790                 let channel_keys_id = Readable::read(reader)?;
3791                 let holder_revocation_basepoint = Readable::read(reader)?;
3792                 // Technically this can fail and serialize fail a round-trip, but only for serialization of
3793                 // barely-init'd ChannelMonitors that we can't do anything with.
3794                 let outpoint = OutPoint {
3795                         txid: Readable::read(reader)?,
3796                         index: Readable::read(reader)?,
3797                 };
3798                 let funding_info = (outpoint, Readable::read(reader)?);
3799                 let current_counterparty_commitment_txid = Readable::read(reader)?;
3800                 let prev_counterparty_commitment_txid = Readable::read(reader)?;
3801
3802                 let counterparty_commitment_params = Readable::read(reader)?;
3803                 let funding_redeemscript = Readable::read(reader)?;
3804                 let channel_value_satoshis = Readable::read(reader)?;
3805
3806                 let their_cur_per_commitment_points = {
3807                         let first_idx = <U48 as Readable>::read(reader)?.0;
3808                         if first_idx == 0 {
3809                                 None
3810                         } else {
3811                                 let first_point = Readable::read(reader)?;
3812                                 let second_point_slice: [u8; 33] = Readable::read(reader)?;
3813                                 if second_point_slice[0..32] == [0; 32] && second_point_slice[32] == 0 {
3814                                         Some((first_idx, first_point, None))
3815                                 } else {
3816                                         Some((first_idx, first_point, Some(unwrap_obj!(PublicKey::from_slice(&second_point_slice)))))
3817                                 }
3818                         }
3819                 };
3820
3821                 let on_holder_tx_csv: u16 = Readable::read(reader)?;
3822
3823                 let commitment_secrets = Readable::read(reader)?;
3824
3825                 macro_rules! read_htlc_in_commitment {
3826                         () => {
3827                                 {
3828                                         let offered: bool = Readable::read(reader)?;
3829                                         let amount_msat: u64 = Readable::read(reader)?;
3830                                         let cltv_expiry: u32 = Readable::read(reader)?;
3831                                         let payment_hash: PaymentHash = Readable::read(reader)?;
3832                                         let transaction_output_index: Option<u32> = Readable::read(reader)?;
3833
3834                                         HTLCOutputInCommitment {
3835                                                 offered, amount_msat, cltv_expiry, payment_hash, transaction_output_index
3836                                         }
3837                                 }
3838                         }
3839                 }
3840
3841                 let counterparty_claimable_outpoints_len: u64 = Readable::read(reader)?;
3842                 let mut counterparty_claimable_outpoints = HashMap::with_capacity(cmp::min(counterparty_claimable_outpoints_len as usize, MAX_ALLOC_SIZE / 64));
3843                 for _ in 0..counterparty_claimable_outpoints_len {
3844                         let txid: Txid = Readable::read(reader)?;
3845                         let htlcs_count: u64 = Readable::read(reader)?;
3846                         let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
3847                         for _ in 0..htlcs_count {
3848                                 htlcs.push((read_htlc_in_commitment!(), <Option<HTLCSource> as Readable>::read(reader)?.map(|o: HTLCSource| Box::new(o))));
3849                         }
3850                         if let Some(_) = counterparty_claimable_outpoints.insert(txid, htlcs) {
3851                                 return Err(DecodeError::InvalidValue);
3852                         }
3853                 }
3854
3855                 let counterparty_commitment_txn_on_chain_len: u64 = Readable::read(reader)?;
3856                 let mut counterparty_commitment_txn_on_chain = HashMap::with_capacity(cmp::min(counterparty_commitment_txn_on_chain_len as usize, MAX_ALLOC_SIZE / 32));
3857                 for _ in 0..counterparty_commitment_txn_on_chain_len {
3858                         let txid: Txid = Readable::read(reader)?;
3859                         let commitment_number = <U48 as Readable>::read(reader)?.0;
3860                         if let Some(_) = counterparty_commitment_txn_on_chain.insert(txid, commitment_number) {
3861                                 return Err(DecodeError::InvalidValue);
3862                         }
3863                 }
3864
3865                 let counterparty_hash_commitment_number_len: u64 = Readable::read(reader)?;
3866                 let mut counterparty_hash_commitment_number = HashMap::with_capacity(cmp::min(counterparty_hash_commitment_number_len as usize, MAX_ALLOC_SIZE / 32));
3867                 for _ in 0..counterparty_hash_commitment_number_len {
3868                         let payment_hash: PaymentHash = Readable::read(reader)?;
3869                         let commitment_number = <U48 as Readable>::read(reader)?.0;
3870                         if let Some(_) = counterparty_hash_commitment_number.insert(payment_hash, commitment_number) {
3871                                 return Err(DecodeError::InvalidValue);
3872                         }
3873                 }
3874
3875                 let mut prev_holder_signed_commitment_tx: Option<HolderSignedTx> =
3876                         match <u8 as Readable>::read(reader)? {
3877                                 0 => None,
3878                                 1 => {
3879                                         Some(Readable::read(reader)?)
3880                                 },
3881                                 _ => return Err(DecodeError::InvalidValue),
3882                         };
3883                 let mut current_holder_commitment_tx: HolderSignedTx = Readable::read(reader)?;
3884
3885                 let current_counterparty_commitment_number = <U48 as Readable>::read(reader)?.0;
3886                 let current_holder_commitment_number = <U48 as Readable>::read(reader)?.0;
3887
3888                 let payment_preimages_len: u64 = Readable::read(reader)?;
3889                 let mut payment_preimages = HashMap::with_capacity(cmp::min(payment_preimages_len as usize, MAX_ALLOC_SIZE / 32));
3890                 for _ in 0..payment_preimages_len {
3891                         let preimage: PaymentPreimage = Readable::read(reader)?;
3892                         let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
3893                         if let Some(_) = payment_preimages.insert(hash, preimage) {
3894                                 return Err(DecodeError::InvalidValue);
3895                         }
3896                 }
3897
3898                 let pending_monitor_events_len: u64 = Readable::read(reader)?;
3899                 let mut pending_monitor_events = Some(
3900                         Vec::with_capacity(cmp::min(pending_monitor_events_len as usize, MAX_ALLOC_SIZE / (32 + 8*3))));
3901                 for _ in 0..pending_monitor_events_len {
3902                         let ev = match <u8 as Readable>::read(reader)? {
3903                                 0 => MonitorEvent::HTLCEvent(Readable::read(reader)?),
3904                                 1 => MonitorEvent::CommitmentTxConfirmed(funding_info.0),
3905                                 _ => return Err(DecodeError::InvalidValue)
3906                         };
3907                         pending_monitor_events.as_mut().unwrap().push(ev);
3908                 }
3909
3910                 let pending_events_len: u64 = Readable::read(reader)?;
3911                 let mut pending_events = Vec::with_capacity(cmp::min(pending_events_len as usize, MAX_ALLOC_SIZE / mem::size_of::<Event>()));
3912                 for _ in 0..pending_events_len {
3913                         if let Some(event) = MaybeReadable::read(reader)? {
3914                                 pending_events.push(event);
3915                         }
3916                 }
3917
3918                 let best_block = BestBlock::new(Readable::read(reader)?, Readable::read(reader)?);
3919
3920                 let waiting_threshold_conf_len: u64 = Readable::read(reader)?;
3921                 let mut onchain_events_awaiting_threshold_conf = Vec::with_capacity(cmp::min(waiting_threshold_conf_len as usize, MAX_ALLOC_SIZE / 128));
3922                 for _ in 0..waiting_threshold_conf_len {
3923                         if let Some(val) = MaybeReadable::read(reader)? {
3924                                 onchain_events_awaiting_threshold_conf.push(val);
3925                         }
3926                 }
3927
3928                 let outputs_to_watch_len: u64 = Readable::read(reader)?;
3929                 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>>())));
3930                 for _ in 0..outputs_to_watch_len {
3931                         let txid = Readable::read(reader)?;
3932                         let outputs_len: u64 = Readable::read(reader)?;
3933                         let mut outputs = Vec::with_capacity(cmp::min(outputs_len as usize, MAX_ALLOC_SIZE / (mem::size_of::<u32>() + mem::size_of::<Script>())));
3934                         for _ in 0..outputs_len {
3935                                 outputs.push((Readable::read(reader)?, Readable::read(reader)?));
3936                         }
3937                         if let Some(_) = outputs_to_watch.insert(txid, outputs) {
3938                                 return Err(DecodeError::InvalidValue);
3939                         }
3940                 }
3941                 let onchain_tx_handler: OnchainTxHandler<SP::Signer> = ReadableArgs::read(
3942                         reader, (entropy_source, signer_provider, channel_value_satoshis, channel_keys_id)
3943                 )?;
3944
3945                 let lockdown_from_offchain = Readable::read(reader)?;
3946                 let holder_tx_signed = Readable::read(reader)?;
3947
3948                 if let Some(prev_commitment_tx) = prev_holder_signed_commitment_tx.as_mut() {
3949                         let prev_holder_value = onchain_tx_handler.get_prev_holder_commitment_to_self_value();
3950                         if prev_holder_value.is_none() { return Err(DecodeError::InvalidValue); }
3951                         if prev_commitment_tx.to_self_value_sat == u64::max_value() {
3952                                 prev_commitment_tx.to_self_value_sat = prev_holder_value.unwrap();
3953                         } else if prev_commitment_tx.to_self_value_sat != prev_holder_value.unwrap() {
3954                                 return Err(DecodeError::InvalidValue);
3955                         }
3956                 }
3957
3958                 let cur_holder_value = onchain_tx_handler.get_cur_holder_commitment_to_self_value();
3959                 if current_holder_commitment_tx.to_self_value_sat == u64::max_value() {
3960                         current_holder_commitment_tx.to_self_value_sat = cur_holder_value;
3961                 } else if current_holder_commitment_tx.to_self_value_sat != cur_holder_value {
3962                         return Err(DecodeError::InvalidValue);
3963                 }
3964
3965                 let mut funding_spend_confirmed = None;
3966                 let mut htlcs_resolved_on_chain = Some(Vec::new());
3967                 let mut funding_spend_seen = Some(false);
3968                 let mut counterparty_node_id = None;
3969                 let mut confirmed_commitment_tx_counterparty_output = None;
3970                 let mut spendable_txids_confirmed = Some(Vec::new());
3971                 let mut counterparty_fulfilled_htlcs = Some(HashMap::new());
3972                 read_tlv_fields!(reader, {
3973                         (1, funding_spend_confirmed, option),
3974                         (3, htlcs_resolved_on_chain, vec_type),
3975                         (5, pending_monitor_events, vec_type),
3976                         (7, funding_spend_seen, option),
3977                         (9, counterparty_node_id, option),
3978                         (11, confirmed_commitment_tx_counterparty_output, option),
3979                         (13, spendable_txids_confirmed, vec_type),
3980                         (15, counterparty_fulfilled_htlcs, option),
3981                 });
3982
3983                 Ok((best_block.block_hash(), ChannelMonitor::from_impl(ChannelMonitorImpl {
3984                         latest_update_id,
3985                         commitment_transaction_number_obscure_factor,
3986
3987                         destination_script,
3988                         broadcasted_holder_revokable_script,
3989                         counterparty_payment_script,
3990                         shutdown_script,
3991
3992                         channel_keys_id,
3993                         holder_revocation_basepoint,
3994                         funding_info,
3995                         current_counterparty_commitment_txid,
3996                         prev_counterparty_commitment_txid,
3997
3998                         counterparty_commitment_params,
3999                         funding_redeemscript,
4000                         channel_value_satoshis,
4001                         their_cur_per_commitment_points,
4002
4003                         on_holder_tx_csv,
4004
4005                         commitment_secrets,
4006                         counterparty_claimable_outpoints,
4007                         counterparty_commitment_txn_on_chain,
4008                         counterparty_hash_commitment_number,
4009                         counterparty_fulfilled_htlcs: counterparty_fulfilled_htlcs.unwrap(),
4010
4011                         prev_holder_signed_commitment_tx,
4012                         current_holder_commitment_tx,
4013                         current_counterparty_commitment_number,
4014                         current_holder_commitment_number,
4015
4016                         payment_preimages,
4017                         pending_monitor_events: pending_monitor_events.unwrap(),
4018                         pending_events,
4019
4020                         onchain_events_awaiting_threshold_conf,
4021                         outputs_to_watch,
4022
4023                         onchain_tx_handler,
4024
4025                         lockdown_from_offchain,
4026                         holder_tx_signed,
4027                         funding_spend_seen: funding_spend_seen.unwrap(),
4028                         funding_spend_confirmed,
4029                         confirmed_commitment_tx_counterparty_output,
4030                         htlcs_resolved_on_chain: htlcs_resolved_on_chain.unwrap(),
4031                         spendable_txids_confirmed: spendable_txids_confirmed.unwrap(),
4032
4033                         best_block,
4034                         counterparty_node_id,
4035                 })))
4036         }
4037 }
4038
4039 #[cfg(test)]
4040 mod tests {
4041         use bitcoin::blockdata::block::BlockHeader;
4042         use bitcoin::blockdata::script::{Script, Builder};
4043         use bitcoin::blockdata::opcodes;
4044         use bitcoin::blockdata::transaction::{Transaction, TxIn, TxOut, EcdsaSighashType};
4045         use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
4046         use bitcoin::util::sighash;
4047         use bitcoin::hashes::Hash;
4048         use bitcoin::hashes::sha256::Hash as Sha256;
4049         use bitcoin::hashes::hex::FromHex;
4050         use bitcoin::hash_types::{BlockHash, Txid};
4051         use bitcoin::network::constants::Network;
4052         use bitcoin::secp256k1::{SecretKey,PublicKey};
4053         use bitcoin::secp256k1::Secp256k1;
4054
4055         use hex;
4056
4057         use crate::chain::chaininterface::LowerBoundedFeeEstimator;
4058
4059         use super::ChannelMonitorUpdateStep;
4060         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};
4061         use crate::chain::{BestBlock, Confirm};
4062         use crate::chain::channelmonitor::ChannelMonitor;
4063         use crate::chain::package::{weight_offered_htlc, weight_received_htlc, weight_revoked_offered_htlc, weight_revoked_received_htlc, WEIGHT_REVOKED_OUTPUT};
4064         use crate::chain::transaction::OutPoint;
4065         use crate::chain::keysinterface::InMemorySigner;
4066         use crate::events::ClosureReason;
4067         use crate::ln::{PaymentPreimage, PaymentHash};
4068         use crate::ln::chan_utils;
4069         use crate::ln::chan_utils::{HTLCOutputInCommitment, ChannelPublicKeys, ChannelTransactionParameters, HolderCommitmentTransaction, CounterpartyChannelTransactionParameters};
4070         use crate::ln::channelmanager::{PaymentSendFailure, PaymentId, RecipientOnionFields};
4071         use crate::ln::functional_test_utils::*;
4072         use crate::ln::script::ShutdownScript;
4073         use crate::util::errors::APIError;
4074         use crate::util::test_utils::{TestLogger, TestBroadcaster, TestFeeEstimator};
4075         use crate::util::ser::{ReadableArgs, Writeable};
4076         use crate::sync::{Arc, Mutex};
4077         use crate::io;
4078         use bitcoin::{PackedLockTime, Sequence, TxMerkleNode, Witness};
4079         use crate::prelude::*;
4080
4081         fn do_test_funding_spend_refuses_updates(use_local_txn: bool) {
4082                 // Previously, monitor updates were allowed freely even after a funding-spend transaction
4083                 // confirmed. This would allow a race condition where we could receive a payment (including
4084                 // the counterparty revoking their broadcasted state!) and accept it without recourse as
4085                 // long as the ChannelMonitor receives the block first, the full commitment update dance
4086                 // occurs after the block is connected, and before the ChannelManager receives the block.
4087                 // Obviously this is an incredibly contrived race given the counterparty would be risking
4088                 // their full channel balance for it, but its worth fixing nonetheless as it makes the
4089                 // potential ChannelMonitor states simpler to reason about.
4090                 //
4091                 // This test checks said behavior, as well as ensuring a ChannelMonitorUpdate with multiple
4092                 // updates is handled correctly in such conditions.
4093                 let chanmon_cfgs = create_chanmon_cfgs(3);
4094                 let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
4095                 let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
4096                 let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
4097                 let channel = create_announced_chan_between_nodes(&nodes, 0, 1);
4098                 create_announced_chan_between_nodes(&nodes, 1, 2);
4099
4100                 // Rebalance somewhat
4101                 send_payment(&nodes[0], &[&nodes[1]], 10_000_000);
4102
4103                 // First route two payments for testing at the end
4104                 let payment_preimage_1 = route_payment(&nodes[0], &[&nodes[1], &nodes[2]], 1_000_000).0;
4105                 let payment_preimage_2 = route_payment(&nodes[0], &[&nodes[1], &nodes[2]], 1_000_000).0;
4106
4107                 let local_txn = get_local_commitment_txn!(nodes[1], channel.2);
4108                 assert_eq!(local_txn.len(), 1);
4109                 let remote_txn = get_local_commitment_txn!(nodes[0], channel.2);
4110                 assert_eq!(remote_txn.len(), 3); // Commitment and two HTLC-Timeouts
4111                 check_spends!(remote_txn[1], remote_txn[0]);
4112                 check_spends!(remote_txn[2], remote_txn[0]);
4113                 let broadcast_tx = if use_local_txn { &local_txn[0] } else { &remote_txn[0] };
4114
4115                 // Connect a commitment transaction, but only to the ChainMonitor/ChannelMonitor. The
4116                 // channel is now closed, but the ChannelManager doesn't know that yet.
4117                 let new_header = BlockHeader {
4118                         version: 2, time: 0, bits: 0, nonce: 0,
4119                         prev_blockhash: nodes[0].best_block_info().0,
4120                         merkle_root: TxMerkleNode::all_zeros() };
4121                 let conf_height = nodes[0].best_block_info().1 + 1;
4122                 nodes[1].chain_monitor.chain_monitor.transactions_confirmed(&new_header,
4123                         &[(0, broadcast_tx)], conf_height);
4124
4125                 let (_, pre_update_monitor) = <(BlockHash, ChannelMonitor<InMemorySigner>)>::read(
4126                                                 &mut io::Cursor::new(&get_monitor!(nodes[1], channel.2).encode()),
4127                                                 (&nodes[1].keys_manager.backing, &nodes[1].keys_manager.backing)).unwrap();
4128
4129                 // If the ChannelManager tries to update the channel, however, the ChainMonitor will pass
4130                 // the update through to the ChannelMonitor which will refuse it (as the channel is closed).
4131                 let (route, payment_hash, _, payment_secret) = get_route_and_payment_hash!(nodes[1], nodes[0], 100_000);
4132                 unwrap_send_err!(nodes[1].node.send_payment_with_route(&route, payment_hash,
4133                                 RecipientOnionFields::secret_only(payment_secret), PaymentId(payment_hash.0)
4134                         ), true, APIError::ChannelUnavailable { ref err },
4135                         assert!(err.contains("ChannelMonitor storage failure")));
4136                 check_added_monitors!(nodes[1], 2); // After the failure we generate a close-channel monitor update
4137                 check_closed_broadcast!(nodes[1], true);
4138                 check_closed_event!(nodes[1], 1, ClosureReason::ProcessingError { err: "ChannelMonitor storage failure".to_string() });
4139
4140                 // Build a new ChannelMonitorUpdate which contains both the failing commitment tx update
4141                 // and provides the claim preimages for the two pending HTLCs. The first update generates
4142                 // an error, but the point of this test is to ensure the later updates are still applied.
4143                 let monitor_updates = nodes[1].chain_monitor.monitor_updates.lock().unwrap();
4144                 let mut replay_update = monitor_updates.get(&channel.2).unwrap().iter().rev().skip(1).next().unwrap().clone();
4145                 assert_eq!(replay_update.updates.len(), 1);
4146                 if let ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo { .. } = replay_update.updates[0] {
4147                 } else { panic!(); }
4148                 replay_update.updates.push(ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage: payment_preimage_1 });
4149                 replay_update.updates.push(ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage: payment_preimage_2 });
4150
4151                 let broadcaster = TestBroadcaster::new(Arc::clone(&nodes[1].blocks));
4152                 assert!(
4153                         pre_update_monitor.update_monitor(&replay_update, &&broadcaster, &chanmon_cfgs[1].fee_estimator, &nodes[1].logger)
4154                         .is_err());
4155                 // Even though we error'd on the first update, we should still have generated an HTLC claim
4156                 // transaction
4157                 let txn_broadcasted = broadcaster.txn_broadcasted.lock().unwrap().split_off(0);
4158                 assert!(txn_broadcasted.len() >= 2);
4159                 let htlc_txn = txn_broadcasted.iter().filter(|tx| {
4160                         assert_eq!(tx.input.len(), 1);
4161                         tx.input[0].previous_output.txid == broadcast_tx.txid()
4162                 }).collect::<Vec<_>>();
4163                 assert_eq!(htlc_txn.len(), 2);
4164                 check_spends!(htlc_txn[0], broadcast_tx);
4165                 check_spends!(htlc_txn[1], broadcast_tx);
4166         }
4167         #[test]
4168         fn test_funding_spend_refuses_updates() {
4169                 do_test_funding_spend_refuses_updates(true);
4170                 do_test_funding_spend_refuses_updates(false);
4171         }
4172
4173         #[test]
4174         fn test_prune_preimages() {
4175                 let secp_ctx = Secp256k1::new();
4176                 let logger = Arc::new(TestLogger::new());
4177                 let broadcaster = Arc::new(TestBroadcaster {
4178                         txn_broadcasted: Mutex::new(Vec::new()),
4179                         blocks: Arc::new(Mutex::new(Vec::new()))
4180                 });
4181                 let fee_estimator = TestFeeEstimator { sat_per_kw: Mutex::new(253) };
4182
4183                 let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
4184
4185                 let mut preimages = Vec::new();
4186                 {
4187                         for i in 0..20 {
4188                                 let preimage = PaymentPreimage([i; 32]);
4189                                 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
4190                                 preimages.push((preimage, hash));
4191                         }
4192                 }
4193
4194                 macro_rules! preimages_slice_to_htlcs {
4195                         ($preimages_slice: expr) => {
4196                                 {
4197                                         let mut res = Vec::new();
4198                                         for (idx, preimage) in $preimages_slice.iter().enumerate() {
4199                                                 res.push((HTLCOutputInCommitment {
4200                                                         offered: true,
4201                                                         amount_msat: 0,
4202                                                         cltv_expiry: 0,
4203                                                         payment_hash: preimage.1.clone(),
4204                                                         transaction_output_index: Some(idx as u32),
4205                                                 }, ()));
4206                                         }
4207                                         res
4208                                 }
4209                         }
4210                 }
4211                 macro_rules! preimages_slice_to_htlc_outputs {
4212                         ($preimages_slice: expr) => {
4213                                 preimages_slice_to_htlcs!($preimages_slice).into_iter().map(|(htlc, _)| (htlc, None)).collect()
4214                         }
4215                 }
4216                 let dummy_sig = crate::util::crypto::sign(&secp_ctx,
4217                         &bitcoin::secp256k1::Message::from_slice(&[42; 32]).unwrap(),
4218                         &SecretKey::from_slice(&[42; 32]).unwrap());
4219
4220                 macro_rules! test_preimages_exist {
4221                         ($preimages_slice: expr, $monitor: expr) => {
4222                                 for preimage in $preimages_slice {
4223                                         assert!($monitor.inner.lock().unwrap().payment_preimages.contains_key(&preimage.1));
4224                                 }
4225                         }
4226                 }
4227
4228                 let keys = InMemorySigner::new(
4229                         &secp_ctx,
4230                         SecretKey::from_slice(&[41; 32]).unwrap(),
4231                         SecretKey::from_slice(&[41; 32]).unwrap(),
4232                         SecretKey::from_slice(&[41; 32]).unwrap(),
4233                         SecretKey::from_slice(&[41; 32]).unwrap(),
4234                         SecretKey::from_slice(&[41; 32]).unwrap(),
4235                         [41; 32],
4236                         0,
4237                         [0; 32],
4238                 );
4239
4240                 let counterparty_pubkeys = ChannelPublicKeys {
4241                         funding_pubkey: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[44; 32]).unwrap()),
4242                         revocation_basepoint: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()),
4243                         payment_point: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[46; 32]).unwrap()),
4244                         delayed_payment_basepoint: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[47; 32]).unwrap()),
4245                         htlc_basepoint: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[48; 32]).unwrap())
4246                 };
4247                 let funding_outpoint = OutPoint { txid: Txid::all_zeros(), index: u16::max_value() };
4248                 let channel_parameters = ChannelTransactionParameters {
4249                         holder_pubkeys: keys.holder_channel_pubkeys.clone(),
4250                         holder_selected_contest_delay: 66,
4251                         is_outbound_from_holder: true,
4252                         counterparty_parameters: Some(CounterpartyChannelTransactionParameters {
4253                                 pubkeys: counterparty_pubkeys,
4254                                 selected_contest_delay: 67,
4255                         }),
4256                         funding_outpoint: Some(funding_outpoint),
4257                         opt_anchors: None,
4258                         opt_non_zero_fee_anchors: None,
4259                 };
4260                 // Prune with one old state and a holder commitment tx holding a few overlaps with the
4261                 // old state.
4262                 let shutdown_pubkey = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
4263                 let best_block = BestBlock::from_network(Network::Testnet);
4264                 let monitor = ChannelMonitor::new(Secp256k1::new(), keys,
4265                         Some(ShutdownScript::new_p2wpkh_from_pubkey(shutdown_pubkey).into_inner()), 0, &Script::new(),
4266                         (OutPoint { txid: Txid::from_slice(&[43; 32]).unwrap(), index: 0 }, Script::new()),
4267                         &channel_parameters, Script::new(), 46, 0, HolderCommitmentTransaction::dummy(&mut Vec::new()),
4268                         best_block, dummy_key);
4269
4270                 let mut htlcs = preimages_slice_to_htlcs!(preimages[0..10]);
4271                 let dummy_commitment_tx = HolderCommitmentTransaction::dummy(&mut htlcs);
4272                 monitor.provide_latest_holder_commitment_tx(dummy_commitment_tx.clone(),
4273                         htlcs.into_iter().map(|(htlc, _)| (htlc, Some(dummy_sig), None)).collect()).unwrap();
4274                 monitor.provide_latest_counterparty_commitment_tx(Txid::from_inner(Sha256::hash(b"1").into_inner()),
4275                         preimages_slice_to_htlc_outputs!(preimages[5..15]), 281474976710655, dummy_key, &logger);
4276                 monitor.provide_latest_counterparty_commitment_tx(Txid::from_inner(Sha256::hash(b"2").into_inner()),
4277                         preimages_slice_to_htlc_outputs!(preimages[15..20]), 281474976710654, dummy_key, &logger);
4278                 for &(ref preimage, ref hash) in preimages.iter() {
4279                         let bounded_fee_estimator = LowerBoundedFeeEstimator::new(&fee_estimator);
4280                         monitor.provide_payment_preimage(hash, preimage, &broadcaster, &bounded_fee_estimator, &logger);
4281                 }
4282
4283                 // Now provide a secret, pruning preimages 10-15
4284                 let mut secret = [0; 32];
4285                 secret[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
4286                 monitor.provide_secret(281474976710655, secret.clone()).unwrap();
4287                 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 15);
4288                 test_preimages_exist!(&preimages[0..10], monitor);
4289                 test_preimages_exist!(&preimages[15..20], monitor);
4290
4291                 monitor.provide_latest_counterparty_commitment_tx(Txid::from_inner(Sha256::hash(b"3").into_inner()),
4292                         preimages_slice_to_htlc_outputs!(preimages[17..20]), 281474976710653, dummy_key, &logger);
4293
4294                 // Now provide a further secret, pruning preimages 15-17
4295                 secret[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
4296                 monitor.provide_secret(281474976710654, secret.clone()).unwrap();
4297                 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 13);
4298                 test_preimages_exist!(&preimages[0..10], monitor);
4299                 test_preimages_exist!(&preimages[17..20], monitor);
4300
4301                 monitor.provide_latest_counterparty_commitment_tx(Txid::from_inner(Sha256::hash(b"4").into_inner()),
4302                         preimages_slice_to_htlc_outputs!(preimages[18..20]), 281474976710652, dummy_key, &logger);
4303
4304                 // Now update holder commitment tx info, pruning only element 18 as we still care about the
4305                 // previous commitment tx's preimages too
4306                 let mut htlcs = preimages_slice_to_htlcs!(preimages[0..5]);
4307                 let dummy_commitment_tx = HolderCommitmentTransaction::dummy(&mut htlcs);
4308                 monitor.provide_latest_holder_commitment_tx(dummy_commitment_tx.clone(),
4309                         htlcs.into_iter().map(|(htlc, _)| (htlc, Some(dummy_sig), None)).collect()).unwrap();
4310                 secret[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
4311                 monitor.provide_secret(281474976710653, secret.clone()).unwrap();
4312                 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 12);
4313                 test_preimages_exist!(&preimages[0..10], monitor);
4314                 test_preimages_exist!(&preimages[18..20], monitor);
4315
4316                 // But if we do it again, we'll prune 5-10
4317                 let mut htlcs = preimages_slice_to_htlcs!(preimages[0..3]);
4318                 let dummy_commitment_tx = HolderCommitmentTransaction::dummy(&mut htlcs);
4319                 monitor.provide_latest_holder_commitment_tx(dummy_commitment_tx,
4320                         htlcs.into_iter().map(|(htlc, _)| (htlc, Some(dummy_sig), None)).collect()).unwrap();
4321                 secret[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
4322                 monitor.provide_secret(281474976710652, secret.clone()).unwrap();
4323                 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 5);
4324                 test_preimages_exist!(&preimages[0..5], monitor);
4325         }
4326
4327         #[test]
4328         fn test_claim_txn_weight_computation() {
4329                 // We test Claim txn weight, knowing that we want expected weigth and
4330                 // not actual case to avoid sigs and time-lock delays hell variances.
4331
4332                 let secp_ctx = Secp256k1::new();
4333                 let privkey = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
4334                 let pubkey = PublicKey::from_secret_key(&secp_ctx, &privkey);
4335
4336                 macro_rules! sign_input {
4337                         ($sighash_parts: expr, $idx: expr, $amount: expr, $weight: expr, $sum_actual_sigs: expr, $opt_anchors: expr) => {
4338                                 let htlc = HTLCOutputInCommitment {
4339                                         offered: if *$weight == weight_revoked_offered_htlc($opt_anchors) || *$weight == weight_offered_htlc($opt_anchors) { true } else { false },
4340                                         amount_msat: 0,
4341                                         cltv_expiry: 2 << 16,
4342                                         payment_hash: PaymentHash([1; 32]),
4343                                         transaction_output_index: Some($idx as u32),
4344                                 };
4345                                 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, $opt_anchors, &pubkey, &pubkey, &pubkey) };
4346                                 let sighash = hash_to_message!(&$sighash_parts.segwit_signature_hash($idx, &redeem_script, $amount, EcdsaSighashType::All).unwrap()[..]);
4347                                 let sig = secp_ctx.sign_ecdsa(&sighash, &privkey);
4348                                 let mut ser_sig = sig.serialize_der().to_vec();
4349                                 ser_sig.push(EcdsaSighashType::All as u8);
4350                                 $sum_actual_sigs += ser_sig.len();
4351                                 let witness = $sighash_parts.witness_mut($idx).unwrap();
4352                                 witness.push(ser_sig);
4353                                 if *$weight == WEIGHT_REVOKED_OUTPUT {
4354                                         witness.push(vec!(1));
4355                                 } else if *$weight == weight_revoked_offered_htlc($opt_anchors) || *$weight == weight_revoked_received_htlc($opt_anchors) {
4356                                         witness.push(pubkey.clone().serialize().to_vec());
4357                                 } else if *$weight == weight_received_htlc($opt_anchors) {
4358                                         witness.push(vec![0]);
4359                                 } else {
4360                                         witness.push(PaymentPreimage([1; 32]).0.to_vec());
4361                                 }
4362                                 witness.push(redeem_script.into_bytes());
4363                                 let witness = witness.to_vec();
4364                                 println!("witness[0] {}", witness[0].len());
4365                                 println!("witness[1] {}", witness[1].len());
4366                                 println!("witness[2] {}", witness[2].len());
4367                         }
4368                 }
4369
4370                 let script_pubkey = Builder::new().push_opcode(opcodes::all::OP_RETURN).into_script();
4371                 let txid = Txid::from_hex("56944c5d3f98413ef45cf54545538103cc9f298e0575820ad3591376e2e0f65d").unwrap();
4372
4373                 // Justice tx with 1 to_holder, 2 revoked offered HTLCs, 1 revoked received HTLCs
4374                 for &opt_anchors in [false, true].iter() {
4375                         let mut claim_tx = Transaction { version: 0, lock_time: PackedLockTime::ZERO, input: Vec::new(), output: Vec::new() };
4376                         let mut sum_actual_sigs = 0;
4377                         for i in 0..4 {
4378                                 claim_tx.input.push(TxIn {
4379                                         previous_output: BitcoinOutPoint {
4380                                                 txid,
4381                                                 vout: i,
4382                                         },
4383                                         script_sig: Script::new(),
4384                                         sequence: Sequence::ENABLE_RBF_NO_LOCKTIME,
4385                                         witness: Witness::new(),
4386                                 });
4387                         }
4388                         claim_tx.output.push(TxOut {
4389                                 script_pubkey: script_pubkey.clone(),
4390                                 value: 0,
4391                         });
4392                         let base_weight = claim_tx.weight();
4393                         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)];
4394                         let mut inputs_total_weight = 2; // count segwit flags
4395                         {
4396                                 let mut sighash_parts = sighash::SighashCache::new(&mut claim_tx);
4397                                 for (idx, inp) in inputs_weight.iter().enumerate() {
4398                                         sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs, opt_anchors);
4399                                         inputs_total_weight += inp;
4400                                 }
4401                         }
4402                         assert_eq!(base_weight + inputs_total_weight as usize,  claim_tx.weight() + /* max_length_sig */ (73 * inputs_weight.len() - sum_actual_sigs));
4403                 }
4404
4405                 // Claim tx with 1 offered HTLCs, 3 received HTLCs
4406                 for &opt_anchors in [false, true].iter() {
4407                         let mut claim_tx = Transaction { version: 0, lock_time: PackedLockTime::ZERO, input: Vec::new(), output: Vec::new() };
4408                         let mut sum_actual_sigs = 0;
4409                         for i in 0..4 {
4410                                 claim_tx.input.push(TxIn {
4411                                         previous_output: BitcoinOutPoint {
4412                                                 txid,
4413                                                 vout: i,
4414                                         },
4415                                         script_sig: Script::new(),
4416                                         sequence: Sequence::ENABLE_RBF_NO_LOCKTIME,
4417                                         witness: Witness::new(),
4418                                 });
4419                         }
4420                         claim_tx.output.push(TxOut {
4421                                 script_pubkey: script_pubkey.clone(),
4422                                 value: 0,
4423                         });
4424                         let base_weight = claim_tx.weight();
4425                         let inputs_weight = vec![weight_offered_htlc(opt_anchors), weight_received_htlc(opt_anchors), weight_received_htlc(opt_anchors), weight_received_htlc(opt_anchors)];
4426                         let mut inputs_total_weight = 2; // count segwit flags
4427                         {
4428                                 let mut sighash_parts = sighash::SighashCache::new(&mut claim_tx);
4429                                 for (idx, inp) in inputs_weight.iter().enumerate() {
4430                                         sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs, opt_anchors);
4431                                         inputs_total_weight += inp;
4432                                 }
4433                         }
4434                         assert_eq!(base_weight + inputs_total_weight as usize,  claim_tx.weight() + /* max_length_sig */ (73 * inputs_weight.len() - sum_actual_sigs));
4435                 }
4436
4437                 // Justice tx with 1 revoked HTLC-Success tx output
4438                 for &opt_anchors in [false, true].iter() {
4439                         let mut claim_tx = Transaction { version: 0, lock_time: PackedLockTime::ZERO, input: Vec::new(), output: Vec::new() };
4440                         let mut sum_actual_sigs = 0;
4441                         claim_tx.input.push(TxIn {
4442                                 previous_output: BitcoinOutPoint {
4443                                         txid,
4444                                         vout: 0,
4445                                 },
4446                                 script_sig: Script::new(),
4447                                 sequence: Sequence::ENABLE_RBF_NO_LOCKTIME,
4448                                 witness: Witness::new(),
4449                         });
4450                         claim_tx.output.push(TxOut {
4451                                 script_pubkey: script_pubkey.clone(),
4452                                 value: 0,
4453                         });
4454                         let base_weight = claim_tx.weight();
4455                         let inputs_weight = vec![WEIGHT_REVOKED_OUTPUT];
4456                         let mut inputs_total_weight = 2; // count segwit flags
4457                         {
4458                                 let mut sighash_parts = sighash::SighashCache::new(&mut claim_tx);
4459                                 for (idx, inp) in inputs_weight.iter().enumerate() {
4460                                         sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs, opt_anchors);
4461                                         inputs_total_weight += inp;
4462                                 }
4463                         }
4464                         assert_eq!(base_weight + inputs_total_weight as usize, claim_tx.weight() + /* max_length_isg */ (73 * inputs_weight.len() - sum_actual_sigs));
4465                 }
4466         }
4467
4468         // Further testing is done in the ChannelManager integration tests.
4469 }