1 // This file is Copyright its original authors, visible in version control
4 // This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
5 // or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
6 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
7 // You may not use this file except in accordance with one or both of these
10 //! Various utilities for building scripts and deriving keys related to channels. These are
11 //! largely of interest for those implementing chain::keysinterface::Sign message signing by hand.
13 use bitcoin::blockdata::script::{Script,Builder};
14 use bitcoin::blockdata::opcodes;
15 use bitcoin::blockdata::transaction::{TxIn,TxOut,OutPoint,Transaction, SigHashType};
16 use bitcoin::util::bip143;
18 use bitcoin::hashes::{Hash, HashEngine};
19 use bitcoin::hashes::sha256::Hash as Sha256;
20 use bitcoin::hashes::ripemd160::Hash as Ripemd160;
21 use bitcoin::hash_types::{Txid, PubkeyHash};
23 use ln::channelmanager::{PaymentHash, PaymentPreimage};
24 use ln::msgs::DecodeError;
25 use util::ser::{Readable, Writeable, Writer, MAX_BUF_SIZE};
28 use bitcoin::hash_types::WPubkeyHash;
29 use bitcoin::secp256k1::key::{SecretKey, PublicKey};
30 use bitcoin::secp256k1::{Secp256k1, Signature, Message};
31 use bitcoin::secp256k1::Error as SecpError;
32 use bitcoin::secp256k1;
36 use util::transaction_utils::sort_outputs;
37 use ln::channel::INITIAL_COMMITMENT_NUMBER;
42 const HTLC_OUTPUT_IN_COMMITMENT_SIZE: usize = 1 + 8 + 4 + 32 + 5;
44 pub(crate) const MAX_HTLCS: u16 = 483;
46 // This checks that the buffer size is greater than the maximum possible size for serialized HTLCS
47 const _EXCESS_BUFFER_SIZE: usize = MAX_BUF_SIZE - MAX_HTLCS as usize * HTLC_OUTPUT_IN_COMMITMENT_SIZE;
49 pub(super) const HTLC_SUCCESS_TX_WEIGHT: u64 = 703;
50 pub(super) const HTLC_TIMEOUT_TX_WEIGHT: u64 = 663;
53 pub(crate) enum HTLCType {
59 /// Check if a given tx witnessScript len matchs one of a pre-signed HTLC
60 pub(crate) fn scriptlen_to_htlctype(witness_script_len: usize) -> Option<HTLCType> {
61 if witness_script_len == 133 {
62 Some(HTLCType::OfferedHTLC)
63 } else if witness_script_len >= 136 && witness_script_len <= 139 {
64 Some(HTLCType::AcceptedHTLC)
71 // Various functions for key derivation and transaction creation for use within channels. Primarily
72 // used in Channel and ChannelMonitor.
74 /// Build the commitment secret from the seed and the commitment number
75 pub fn build_commitment_secret(commitment_seed: &[u8; 32], idx: u64) -> [u8; 32] {
76 let mut res: [u8; 32] = commitment_seed.clone();
79 if idx & (1 << bitpos) == (1 << bitpos) {
80 res[bitpos / 8] ^= 1 << (bitpos & 7);
81 res = Sha256::hash(&res).into_inner();
87 /// Implements the per-commitment secret storage scheme from
88 /// [BOLT 3](https://github.com/lightningnetwork/lightning-rfc/blob/dcbf8583976df087c79c3ce0b535311212e6812d/03-transactions.md#efficient-per-commitment-secret-storage).
90 /// Allows us to keep track of all of the revocation secrets of counterarties in just 50*32 bytes
93 pub(crate) struct CounterpartyCommitmentSecrets {
94 old_secrets: [([u8; 32], u64); 49],
97 impl PartialEq for CounterpartyCommitmentSecrets {
98 fn eq(&self, other: &Self) -> bool {
99 for (&(ref secret, ref idx), &(ref o_secret, ref o_idx)) in self.old_secrets.iter().zip(other.old_secrets.iter()) {
100 if secret != o_secret || idx != o_idx {
108 impl CounterpartyCommitmentSecrets {
109 pub(crate) fn new() -> Self {
110 Self { old_secrets: [([0; 32], 1 << 48); 49], }
114 fn place_secret(idx: u64) -> u8 {
116 if idx & (1 << i) == (1 << i) {
123 pub(crate) fn get_min_seen_secret(&self) -> u64 {
124 //TODO This can be optimized?
125 let mut min = 1 << 48;
126 for &(_, idx) in self.old_secrets.iter() {
135 fn derive_secret(secret: [u8; 32], bits: u8, idx: u64) -> [u8; 32] {
136 let mut res: [u8; 32] = secret;
138 let bitpos = bits - 1 - i;
139 if idx & (1 << bitpos) == (1 << bitpos) {
140 res[(bitpos / 8) as usize] ^= 1 << (bitpos & 7);
141 res = Sha256::hash(&res).into_inner();
147 pub(crate) fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), ()> {
148 let pos = Self::place_secret(idx);
150 let (old_secret, old_idx) = self.old_secrets[i as usize];
151 if Self::derive_secret(secret, pos, old_idx) != old_secret {
155 if self.get_min_seen_secret() <= idx {
158 self.old_secrets[pos as usize] = (secret, idx);
162 /// Can only fail if idx is < get_min_seen_secret
163 pub(crate) fn get_secret(&self, idx: u64) -> Option<[u8; 32]> {
164 for i in 0..self.old_secrets.len() {
165 if (idx & (!((1 << i) - 1))) == self.old_secrets[i].1 {
166 return Some(Self::derive_secret(self.old_secrets[i].0, i as u8, idx))
169 assert!(idx < self.get_min_seen_secret());
174 impl Writeable for CounterpartyCommitmentSecrets {
175 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
176 for &(ref secret, ref idx) in self.old_secrets.iter() {
177 writer.write_all(secret)?;
178 writer.write_all(&byte_utils::be64_to_array(*idx))?;
183 impl Readable for CounterpartyCommitmentSecrets {
184 fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
185 let mut old_secrets = [([0; 32], 1 << 48); 49];
186 for &mut (ref mut secret, ref mut idx) in old_secrets.iter_mut() {
187 *secret = Readable::read(reader)?;
188 *idx = Readable::read(reader)?;
191 Ok(Self { old_secrets })
195 /// Derives a per-commitment-transaction private key (eg an htlc key or delayed_payment key)
196 /// from the base secret and the per_commitment_point.
198 /// Note that this is infallible iff we trust that at least one of the two input keys are randomly
199 /// generated (ie our own).
200 pub fn derive_private_key<T: secp256k1::Signing>(secp_ctx: &Secp256k1<T>, per_commitment_point: &PublicKey, base_secret: &SecretKey) -> Result<SecretKey, SecpError> {
201 let mut sha = Sha256::engine();
202 sha.input(&per_commitment_point.serialize());
203 sha.input(&PublicKey::from_secret_key(&secp_ctx, &base_secret).serialize());
204 let res = Sha256::from_engine(sha).into_inner();
206 let mut key = base_secret.clone();
207 key.add_assign(&res)?;
211 /// Derives a per-commitment-transaction public key (eg an htlc key or a delayed_payment key)
212 /// from the base point and the per_commitment_key. This is the public equivalent of
213 /// derive_private_key - using only public keys to derive a public key instead of private keys.
215 /// Note that this is infallible iff we trust that at least one of the two input keys are randomly
216 /// generated (ie our own).
217 pub fn derive_public_key<T: secp256k1::Signing>(secp_ctx: &Secp256k1<T>, per_commitment_point: &PublicKey, base_point: &PublicKey) -> Result<PublicKey, SecpError> {
218 let mut sha = Sha256::engine();
219 sha.input(&per_commitment_point.serialize());
220 sha.input(&base_point.serialize());
221 let res = Sha256::from_engine(sha).into_inner();
223 let hashkey = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&res)?);
224 base_point.combine(&hashkey)
227 /// Derives a per-commitment-transaction revocation key from its constituent parts.
229 /// Only the cheating participant owns a valid witness to propagate a revoked
230 /// commitment transaction, thus per_commitment_secret always come from cheater
231 /// and revocation_base_secret always come from punisher, which is the broadcaster
232 /// of the transaction spending with this key knowledge.
234 /// Note that this is infallible iff we trust that at least one of the two input keys are randomly
235 /// generated (ie our own).
236 pub fn derive_private_revocation_key<T: secp256k1::Signing>(secp_ctx: &Secp256k1<T>, per_commitment_secret: &SecretKey, countersignatory_revocation_base_secret: &SecretKey) -> Result<SecretKey, SecpError> {
237 let countersignatory_revocation_base_point = PublicKey::from_secret_key(&secp_ctx, &countersignatory_revocation_base_secret);
238 let per_commitment_point = PublicKey::from_secret_key(&secp_ctx, &per_commitment_secret);
240 let rev_append_commit_hash_key = {
241 let mut sha = Sha256::engine();
242 sha.input(&countersignatory_revocation_base_point.serialize());
243 sha.input(&per_commitment_point.serialize());
245 Sha256::from_engine(sha).into_inner()
247 let commit_append_rev_hash_key = {
248 let mut sha = Sha256::engine();
249 sha.input(&per_commitment_point.serialize());
250 sha.input(&countersignatory_revocation_base_point.serialize());
252 Sha256::from_engine(sha).into_inner()
255 let mut countersignatory_contrib = countersignatory_revocation_base_secret.clone();
256 countersignatory_contrib.mul_assign(&rev_append_commit_hash_key)?;
257 let mut broadcaster_contrib = per_commitment_secret.clone();
258 broadcaster_contrib.mul_assign(&commit_append_rev_hash_key)?;
259 countersignatory_contrib.add_assign(&broadcaster_contrib[..])?;
260 Ok(countersignatory_contrib)
263 /// Derives a per-commitment-transaction revocation public key from its constituent parts. This is
264 /// the public equivalend of derive_private_revocation_key - using only public keys to derive a
265 /// public key instead of private keys.
267 /// Only the cheating participant owns a valid witness to propagate a revoked
268 /// commitment transaction, thus per_commitment_point always come from cheater
269 /// and revocation_base_point always come from punisher, which is the broadcaster
270 /// of the transaction spending with this key knowledge.
272 /// Note that this is infallible iff we trust that at least one of the two input keys are randomly
273 /// generated (ie our own).
274 pub fn derive_public_revocation_key<T: secp256k1::Verification>(secp_ctx: &Secp256k1<T>, per_commitment_point: &PublicKey, countersignatory_revocation_base_point: &PublicKey) -> Result<PublicKey, SecpError> {
275 let rev_append_commit_hash_key = {
276 let mut sha = Sha256::engine();
277 sha.input(&countersignatory_revocation_base_point.serialize());
278 sha.input(&per_commitment_point.serialize());
280 Sha256::from_engine(sha).into_inner()
282 let commit_append_rev_hash_key = {
283 let mut sha = Sha256::engine();
284 sha.input(&per_commitment_point.serialize());
285 sha.input(&countersignatory_revocation_base_point.serialize());
287 Sha256::from_engine(sha).into_inner()
290 let mut countersignatory_contrib = countersignatory_revocation_base_point.clone();
291 countersignatory_contrib.mul_assign(&secp_ctx, &rev_append_commit_hash_key)?;
292 let mut broadcaster_contrib = per_commitment_point.clone();
293 broadcaster_contrib.mul_assign(&secp_ctx, &commit_append_rev_hash_key)?;
294 countersignatory_contrib.combine(&broadcaster_contrib)
297 /// The set of public keys which are used in the creation of one commitment transaction.
298 /// These are derived from the channel base keys and per-commitment data.
300 /// A broadcaster key is provided from potential broadcaster of the computed transaction.
301 /// A countersignatory key is coming from a protocol participant unable to broadcast the
304 /// These keys are assumed to be good, either because the code derived them from
305 /// channel basepoints via the new function, or they were obtained via
306 /// CommitmentTransaction.trust().keys() because we trusted the source of the
307 /// pre-calculated keys.
308 #[derive(PartialEq, Clone)]
309 pub struct TxCreationKeys {
310 /// The broadcaster's per-commitment public key which was used to derive the other keys.
311 pub per_commitment_point: PublicKey,
312 /// The revocation key which is used to allow the broadcaster of the commitment
313 /// transaction to provide their counterparty the ability to punish them if they broadcast
315 pub revocation_key: PublicKey,
316 /// Broadcaster's HTLC Key
317 pub broadcaster_htlc_key: PublicKey,
318 /// Countersignatory's HTLC Key
319 pub countersignatory_htlc_key: PublicKey,
320 /// Broadcaster's Payment Key (which isn't allowed to be spent from for some delay)
321 pub broadcaster_delayed_payment_key: PublicKey,
323 impl_writeable!(TxCreationKeys, 33*6,
324 { per_commitment_point, revocation_key, broadcaster_htlc_key, countersignatory_htlc_key, broadcaster_delayed_payment_key });
326 /// One counterparty's public keys which do not change over the life of a channel.
327 #[derive(Clone, PartialEq)]
328 pub struct ChannelPublicKeys {
329 /// The public key which is used to sign all commitment transactions, as it appears in the
330 /// on-chain channel lock-in 2-of-2 multisig output.
331 pub funding_pubkey: PublicKey,
332 /// The base point which is used (with derive_public_revocation_key) to derive per-commitment
333 /// revocation keys. This is combined with the per-commitment-secret generated by the
334 /// counterparty to create a secret which the counterparty can reveal to revoke previous
336 pub revocation_basepoint: PublicKey,
337 /// The public key on which the non-broadcaster (ie the countersignatory) receives an immediately
338 /// spendable primary channel balance on the broadcaster's commitment transaction. This key is
339 /// static across every commitment transaction.
340 pub payment_point: PublicKey,
341 /// The base point which is used (with derive_public_key) to derive a per-commitment payment
342 /// public key which receives non-HTLC-encumbered funds which are only available for spending
343 /// after some delay (or can be claimed via the revocation path).
344 pub delayed_payment_basepoint: PublicKey,
345 /// The base point which is used (with derive_public_key) to derive a per-commitment public key
346 /// which is used to encumber HTLC-in-flight outputs.
347 pub htlc_basepoint: PublicKey,
350 impl_writeable!(ChannelPublicKeys, 33*5, {
352 revocation_basepoint,
354 delayed_payment_basepoint,
359 impl TxCreationKeys {
360 /// Create per-state keys from channel base points and the per-commitment point.
361 /// Key set is asymmetric and can't be used as part of counter-signatory set of transactions.
362 pub fn derive_new<T: secp256k1::Signing + secp256k1::Verification>(secp_ctx: &Secp256k1<T>, per_commitment_point: &PublicKey, broadcaster_delayed_payment_base: &PublicKey, broadcaster_htlc_base: &PublicKey, countersignatory_revocation_base: &PublicKey, countersignatory_htlc_base: &PublicKey) -> Result<TxCreationKeys, SecpError> {
364 per_commitment_point: per_commitment_point.clone(),
365 revocation_key: derive_public_revocation_key(&secp_ctx, &per_commitment_point, &countersignatory_revocation_base)?,
366 broadcaster_htlc_key: derive_public_key(&secp_ctx, &per_commitment_point, &broadcaster_htlc_base)?,
367 countersignatory_htlc_key: derive_public_key(&secp_ctx, &per_commitment_point, &countersignatory_htlc_base)?,
368 broadcaster_delayed_payment_key: derive_public_key(&secp_ctx, &per_commitment_point, &broadcaster_delayed_payment_base)?,
372 /// Generate per-state keys from channel static keys.
373 /// Key set is asymmetric and can't be used as part of counter-signatory set of transactions.
374 pub fn from_channel_static_keys<T: secp256k1::Signing + secp256k1::Verification>(per_commitment_point: &PublicKey, broadcaster_keys: &ChannelPublicKeys, countersignatory_keys: &ChannelPublicKeys, secp_ctx: &Secp256k1<T>) -> Result<TxCreationKeys, SecpError> {
375 TxCreationKeys::derive_new(
377 &per_commitment_point,
378 &broadcaster_keys.delayed_payment_basepoint,
379 &broadcaster_keys.htlc_basepoint,
380 &countersignatory_keys.revocation_basepoint,
381 &countersignatory_keys.htlc_basepoint,
386 /// The maximum length of a script returned by get_revokeable_redeemscript.
387 // Calculated as 6 bytes of opcodes, 1 byte push plus 2 bytes for contest_delay, and two public
388 // keys of 33 bytes (+ 1 push).
389 pub const REVOKEABLE_REDEEMSCRIPT_MAX_LENGTH: usize = 6 + 3 + 34*2;
391 /// A script either spendable by the revocation
392 /// key or the broadcaster_delayed_payment_key and satisfying the relative-locktime OP_CSV constrain.
393 /// Encumbering a `to_holder` output on a commitment transaction or 2nd-stage HTLC transactions.
394 pub fn get_revokeable_redeemscript(revocation_key: &PublicKey, contest_delay: u16, broadcaster_delayed_payment_key: &PublicKey) -> Script {
395 let res = Builder::new().push_opcode(opcodes::all::OP_IF)
396 .push_slice(&revocation_key.serialize())
397 .push_opcode(opcodes::all::OP_ELSE)
398 .push_int(contest_delay as i64)
399 .push_opcode(opcodes::all::OP_CSV)
400 .push_opcode(opcodes::all::OP_DROP)
401 .push_slice(&broadcaster_delayed_payment_key.serialize())
402 .push_opcode(opcodes::all::OP_ENDIF)
403 .push_opcode(opcodes::all::OP_CHECKSIG)
405 debug_assert!(res.len() <= REVOKEABLE_REDEEMSCRIPT_MAX_LENGTH);
409 #[derive(Clone, PartialEq)]
410 /// Information about an HTLC as it appears in a commitment transaction
411 pub struct HTLCOutputInCommitment {
412 /// Whether the HTLC was "offered" (ie outbound in relation to this commitment transaction).
413 /// Note that this is not the same as whether it is ountbound *from us*. To determine that you
414 /// need to compare this value to whether the commitment transaction in question is that of
415 /// the counterparty or our own.
417 /// The value, in msat, of the HTLC. The value as it appears in the commitment transaction is
418 /// this divided by 1000.
419 pub amount_msat: u64,
420 /// The CLTV lock-time at which this HTLC expires.
421 pub cltv_expiry: u32,
422 /// The hash of the preimage which unlocks this HTLC.
423 pub payment_hash: PaymentHash,
424 /// The position within the commitment transactions' outputs. This may be None if the value is
425 /// below the dust limit (in which case no output appears in the commitment transaction and the
426 /// value is spent to additional transaction fees).
427 pub transaction_output_index: Option<u32>,
430 impl_writeable!(HTLCOutputInCommitment, HTLC_OUTPUT_IN_COMMITMENT_SIZE, {
435 transaction_output_index
439 pub(crate) fn get_htlc_redeemscript_with_explicit_keys(htlc: &HTLCOutputInCommitment, broadcaster_htlc_key: &PublicKey, countersignatory_htlc_key: &PublicKey, revocation_key: &PublicKey) -> Script {
440 let payment_hash160 = Ripemd160::hash(&htlc.payment_hash.0[..]).into_inner();
442 Builder::new().push_opcode(opcodes::all::OP_DUP)
443 .push_opcode(opcodes::all::OP_HASH160)
444 .push_slice(&PubkeyHash::hash(&revocation_key.serialize())[..])
445 .push_opcode(opcodes::all::OP_EQUAL)
446 .push_opcode(opcodes::all::OP_IF)
447 .push_opcode(opcodes::all::OP_CHECKSIG)
448 .push_opcode(opcodes::all::OP_ELSE)
449 .push_slice(&countersignatory_htlc_key.serialize()[..])
450 .push_opcode(opcodes::all::OP_SWAP)
451 .push_opcode(opcodes::all::OP_SIZE)
453 .push_opcode(opcodes::all::OP_EQUAL)
454 .push_opcode(opcodes::all::OP_NOTIF)
455 .push_opcode(opcodes::all::OP_DROP)
457 .push_opcode(opcodes::all::OP_SWAP)
458 .push_slice(&broadcaster_htlc_key.serialize()[..])
460 .push_opcode(opcodes::all::OP_CHECKMULTISIG)
461 .push_opcode(opcodes::all::OP_ELSE)
462 .push_opcode(opcodes::all::OP_HASH160)
463 .push_slice(&payment_hash160)
464 .push_opcode(opcodes::all::OP_EQUALVERIFY)
465 .push_opcode(opcodes::all::OP_CHECKSIG)
466 .push_opcode(opcodes::all::OP_ENDIF)
467 .push_opcode(opcodes::all::OP_ENDIF)
470 Builder::new().push_opcode(opcodes::all::OP_DUP)
471 .push_opcode(opcodes::all::OP_HASH160)
472 .push_slice(&PubkeyHash::hash(&revocation_key.serialize())[..])
473 .push_opcode(opcodes::all::OP_EQUAL)
474 .push_opcode(opcodes::all::OP_IF)
475 .push_opcode(opcodes::all::OP_CHECKSIG)
476 .push_opcode(opcodes::all::OP_ELSE)
477 .push_slice(&countersignatory_htlc_key.serialize()[..])
478 .push_opcode(opcodes::all::OP_SWAP)
479 .push_opcode(opcodes::all::OP_SIZE)
481 .push_opcode(opcodes::all::OP_EQUAL)
482 .push_opcode(opcodes::all::OP_IF)
483 .push_opcode(opcodes::all::OP_HASH160)
484 .push_slice(&payment_hash160)
485 .push_opcode(opcodes::all::OP_EQUALVERIFY)
487 .push_opcode(opcodes::all::OP_SWAP)
488 .push_slice(&broadcaster_htlc_key.serialize()[..])
490 .push_opcode(opcodes::all::OP_CHECKMULTISIG)
491 .push_opcode(opcodes::all::OP_ELSE)
492 .push_opcode(opcodes::all::OP_DROP)
493 .push_int(htlc.cltv_expiry as i64)
494 .push_opcode(opcodes::all::OP_CLTV)
495 .push_opcode(opcodes::all::OP_DROP)
496 .push_opcode(opcodes::all::OP_CHECKSIG)
497 .push_opcode(opcodes::all::OP_ENDIF)
498 .push_opcode(opcodes::all::OP_ENDIF)
503 /// Gets the witness redeemscript for an HTLC output in a commitment transaction. Note that htlc
504 /// does not need to have its previous_output_index filled.
506 pub fn get_htlc_redeemscript(htlc: &HTLCOutputInCommitment, keys: &TxCreationKeys) -> Script {
507 get_htlc_redeemscript_with_explicit_keys(htlc, &keys.broadcaster_htlc_key, &keys.countersignatory_htlc_key, &keys.revocation_key)
510 /// Gets the redeemscript for a funding output from the two funding public keys.
511 /// Note that the order of funding public keys does not matter.
512 pub fn make_funding_redeemscript(broadcaster: &PublicKey, countersignatory: &PublicKey) -> Script {
513 let broadcaster_funding_key = broadcaster.serialize();
514 let countersignatory_funding_key = countersignatory.serialize();
516 let builder = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2);
517 if broadcaster_funding_key[..] < countersignatory_funding_key[..] {
518 builder.push_slice(&broadcaster_funding_key)
519 .push_slice(&countersignatory_funding_key)
521 builder.push_slice(&countersignatory_funding_key)
522 .push_slice(&broadcaster_funding_key)
523 }.push_opcode(opcodes::all::OP_PUSHNUM_2).push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script()
526 /// panics if htlc.transaction_output_index.is_none()!
527 pub fn build_htlc_transaction(prev_hash: &Txid, feerate_per_kw: u32, contest_delay: u16, htlc: &HTLCOutputInCommitment, broadcaster_delayed_payment_key: &PublicKey, revocation_key: &PublicKey) -> Transaction {
528 let mut txins: Vec<TxIn> = Vec::new();
530 previous_output: OutPoint {
531 txid: prev_hash.clone(),
532 vout: htlc.transaction_output_index.expect("Can't build an HTLC transaction for a dust output"),
534 script_sig: Script::new(),
539 let total_fee = if htlc.offered {
540 feerate_per_kw as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000
542 feerate_per_kw as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000
545 let mut txouts: Vec<TxOut> = Vec::new();
547 script_pubkey: get_revokeable_redeemscript(revocation_key, contest_delay, broadcaster_delayed_payment_key).to_v0_p2wsh(),
548 value: htlc.amount_msat / 1000 - total_fee //TODO: BOLT 3 does not specify if we should add amount_msat before dividing or if we should divide by 1000 before subtracting (as we do here)
553 lock_time: if htlc.offered { htlc.cltv_expiry } else { 0 },
559 /// Per-channel data used to build transactions in conjunction with the per-commitment data (CommitmentTransaction).
560 /// The fields are organized by holder/counterparty.
562 /// Normally, this is converted to the broadcaster/countersignatory-organized DirectedChannelTransactionParameters
563 /// before use, via the as_holder_broadcastable and as_counterparty_broadcastable functions.
565 pub struct ChannelTransactionParameters {
566 /// Holder public keys
567 pub holder_pubkeys: ChannelPublicKeys,
568 /// The contest delay selected by the holder, which applies to counterparty-broadcast transactions
569 pub holder_selected_contest_delay: u16,
570 /// Whether the holder is the initiator of this channel.
571 /// This is an input to the commitment number obscure factor computation.
572 pub is_outbound_from_holder: bool,
573 /// The late-bound counterparty channel transaction parameters.
574 /// These parameters are populated at the point in the protocol where the counterparty provides them.
575 pub counterparty_parameters: Option<CounterpartyChannelTransactionParameters>,
576 /// The late-bound funding outpoint
577 pub funding_outpoint: Option<chain::transaction::OutPoint>,
580 /// Late-bound per-channel counterparty data used to build transactions.
582 pub struct CounterpartyChannelTransactionParameters {
583 /// Counter-party public keys
584 pub pubkeys: ChannelPublicKeys,
585 /// The contest delay selected by the counterparty, which applies to holder-broadcast transactions
586 pub selected_contest_delay: u16,
589 impl ChannelTransactionParameters {
590 /// Whether the late bound parameters are populated.
591 pub fn is_populated(&self) -> bool {
592 self.counterparty_parameters.is_some() && self.funding_outpoint.is_some()
595 /// Convert the holder/counterparty parameters to broadcaster/countersignatory-organized parameters,
596 /// given that the holder is the broadcaster.
598 /// self.is_populated() must be true before calling this function.
599 pub fn as_holder_broadcastable(&self) -> DirectedChannelTransactionParameters {
600 assert!(self.is_populated(), "self.late_parameters must be set before using as_holder_broadcastable");
601 DirectedChannelTransactionParameters {
603 holder_is_broadcaster: true
607 /// Convert the holder/counterparty parameters to broadcaster/countersignatory-organized parameters,
608 /// given that the counterparty is the broadcaster.
610 /// self.is_populated() must be true before calling this function.
611 pub fn as_counterparty_broadcastable(&self) -> DirectedChannelTransactionParameters {
612 assert!(self.is_populated(), "self.late_parameters must be set before using as_counterparty_broadcastable");
613 DirectedChannelTransactionParameters {
615 holder_is_broadcaster: false
620 impl_writeable!(CounterpartyChannelTransactionParameters, 0, {
622 selected_contest_delay
625 impl_writeable!(ChannelTransactionParameters, 0, {
627 holder_selected_contest_delay,
628 is_outbound_from_holder,
629 counterparty_parameters,
633 /// Static channel fields used to build transactions given per-commitment fields, organized by
634 /// broadcaster/countersignatory.
636 /// This is derived from the holder/counterparty-organized ChannelTransactionParameters via the
637 /// as_holder_broadcastable and as_counterparty_broadcastable functions.
638 pub struct DirectedChannelTransactionParameters<'a> {
639 /// The holder's channel static parameters
640 inner: &'a ChannelTransactionParameters,
641 /// Whether the holder is the broadcaster
642 holder_is_broadcaster: bool,
645 impl<'a> DirectedChannelTransactionParameters<'a> {
646 /// Get the channel pubkeys for the broadcaster
647 pub fn broadcaster_pubkeys(&self) -> &ChannelPublicKeys {
648 if self.holder_is_broadcaster {
649 &self.inner.holder_pubkeys
651 &self.inner.counterparty_parameters.as_ref().unwrap().pubkeys
655 /// Get the channel pubkeys for the countersignatory
656 pub fn countersignatory_pubkeys(&self) -> &ChannelPublicKeys {
657 if self.holder_is_broadcaster {
658 &self.inner.counterparty_parameters.as_ref().unwrap().pubkeys
660 &self.inner.holder_pubkeys
664 /// Get the contest delay applicable to the transactions.
665 /// Note that the contest delay was selected by the countersignatory.
666 pub fn contest_delay(&self) -> u16 {
667 let counterparty_parameters = self.inner.counterparty_parameters.as_ref().unwrap();
668 if self.holder_is_broadcaster { counterparty_parameters.selected_contest_delay } else { self.inner.holder_selected_contest_delay }
671 /// Whether the channel is outbound from the broadcaster.
673 /// The boolean representing the side that initiated the channel is
674 /// an input to the commitment number obscure factor computation.
675 pub fn is_outbound(&self) -> bool {
676 if self.holder_is_broadcaster { self.inner.is_outbound_from_holder } else { !self.inner.is_outbound_from_holder }
679 /// The funding outpoint
680 pub fn funding_outpoint(&self) -> OutPoint {
681 self.inner.funding_outpoint.unwrap().into_bitcoin_outpoint()
685 /// Information needed to build and sign a holder's commitment transaction.
687 /// The transaction is only signed once we are ready to broadcast.
689 pub struct HolderCommitmentTransaction {
690 inner: CommitmentTransaction,
691 /// Our counterparty's signature for the transaction
692 pub counterparty_sig: Signature,
693 /// All non-dust counterparty HTLC signatures, in the order they appear in the transaction
694 pub counterparty_htlc_sigs: Vec<Signature>,
695 // Which order the signatures should go in when constructing the final commitment tx witness.
696 // The user should be able to reconstruct this themselves, so we don't bother to expose it.
697 holder_sig_first: bool,
700 impl Deref for HolderCommitmentTransaction {
701 type Target = CommitmentTransaction;
703 fn deref(&self) -> &Self::Target { &self.inner }
706 impl PartialEq for HolderCommitmentTransaction {
707 // We dont care whether we are signed in equality comparison
708 fn eq(&self, o: &Self) -> bool {
709 self.inner == o.inner
713 impl_writeable!(HolderCommitmentTransaction, 0, {
714 inner, counterparty_sig, counterparty_htlc_sigs, holder_sig_first
717 impl HolderCommitmentTransaction {
719 pub fn dummy() -> Self {
720 let secp_ctx = Secp256k1::new();
721 let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
722 let dummy_sig = secp_ctx.sign(&secp256k1::Message::from_slice(&[42; 32]).unwrap(), &SecretKey::from_slice(&[42; 32]).unwrap());
724 let keys = TxCreationKeys {
725 per_commitment_point: dummy_key.clone(),
726 revocation_key: dummy_key.clone(),
727 broadcaster_htlc_key: dummy_key.clone(),
728 countersignatory_htlc_key: dummy_key.clone(),
729 broadcaster_delayed_payment_key: dummy_key.clone(),
731 let channel_pubkeys = ChannelPublicKeys {
732 funding_pubkey: dummy_key.clone(),
733 revocation_basepoint: dummy_key.clone(),
734 payment_point: dummy_key.clone(),
735 delayed_payment_basepoint: dummy_key.clone(),
736 htlc_basepoint: dummy_key.clone()
738 let channel_parameters = ChannelTransactionParameters {
739 holder_pubkeys: channel_pubkeys.clone(),
740 holder_selected_contest_delay: 0,
741 is_outbound_from_holder: false,
742 counterparty_parameters: Some(CounterpartyChannelTransactionParameters { pubkeys: channel_pubkeys.clone(), selected_contest_delay: 0 }),
743 funding_outpoint: Some(chain::transaction::OutPoint { txid: Default::default(), index: 0 })
745 let mut htlcs_with_aux: Vec<(_, ())> = Vec::new();
746 let inner = CommitmentTransaction::new_with_auxiliary_htlc_data(0, 0, 0, keys, 0, &mut htlcs_with_aux, &channel_parameters.as_counterparty_broadcastable());
747 HolderCommitmentTransaction {
749 counterparty_sig: dummy_sig,
750 counterparty_htlc_sigs: Vec::new(),
751 holder_sig_first: false
755 /// Create a new holder transaction with the given counterparty signatures.
756 /// The funding keys are used to figure out which signature should go first when building the transaction for broadcast.
757 pub fn new(commitment_tx: CommitmentTransaction, counterparty_sig: Signature, counterparty_htlc_sigs: Vec<Signature>, holder_funding_key: &PublicKey, counterparty_funding_key: &PublicKey) -> Self {
759 inner: commitment_tx,
761 counterparty_htlc_sigs,
762 holder_sig_first: holder_funding_key.serialize()[..] < counterparty_funding_key.serialize()[..],
766 pub(crate) fn add_holder_sig(&self, funding_redeemscript: &Script, holder_sig: Signature) -> Transaction {
767 // First push the multisig dummy, note that due to BIP147 (NULLDUMMY) it must be a zero-length element.
768 let mut tx = self.inner.built.transaction.clone();
769 tx.input[0].witness.push(Vec::new());
771 if self.holder_sig_first {
772 tx.input[0].witness.push(holder_sig.serialize_der().to_vec());
773 tx.input[0].witness.push(self.counterparty_sig.serialize_der().to_vec());
775 tx.input[0].witness.push(self.counterparty_sig.serialize_der().to_vec());
776 tx.input[0].witness.push(holder_sig.serialize_der().to_vec());
778 tx.input[0].witness[1].push(SigHashType::All as u8);
779 tx.input[0].witness[2].push(SigHashType::All as u8);
781 tx.input[0].witness.push(funding_redeemscript.as_bytes().to_vec());
786 /// A pre-built Bitcoin commitment transaction and its txid.
788 pub struct BuiltCommitmentTransaction {
789 /// The commitment transaction
790 pub transaction: Transaction,
791 /// The txid for the commitment transaction.
793 /// This is provided as a performance optimization, instead of calling transaction.txid()
798 impl_writeable!(BuiltCommitmentTransaction, 0, { transaction, txid });
800 impl BuiltCommitmentTransaction {
801 /// Get the SIGHASH_ALL sighash value of the transaction.
803 /// This can be used to verify a signature.
804 pub fn get_sighash_all(&self, funding_redeemscript: &Script, channel_value_satoshis: u64) -> Message {
805 let sighash = &bip143::SigHashCache::new(&self.transaction).signature_hash(0, funding_redeemscript, channel_value_satoshis, SigHashType::All)[..];
806 hash_to_message!(sighash)
809 /// Sign a transaction, either because we are counter-signing the counterparty's transaction or
810 /// because we are about to broadcast a holder transaction.
811 pub fn sign<T: secp256k1::Signing>(&self, funding_key: &SecretKey, funding_redeemscript: &Script, channel_value_satoshis: u64, secp_ctx: &Secp256k1<T>) -> Signature {
812 let sighash = self.get_sighash_all(funding_redeemscript, channel_value_satoshis);
813 secp_ctx.sign(&sighash, funding_key)
817 /// This class tracks the per-transaction information needed to build a commitment transaction and to
818 /// actually build it and sign. It is used for holder transactions that we sign only when needed
819 /// and for transactions we sign for the counterparty.
821 /// This class can be used inside a signer implementation to generate a signature given the relevant
824 pub struct CommitmentTransaction {
825 commitment_number: u64,
826 to_broadcaster_value_sat: u64,
827 to_countersignatory_value_sat: u64,
829 htlcs: Vec<HTLCOutputInCommitment>,
830 // A cache of the parties' pubkeys required to construct the transaction, see doc for trust()
831 keys: TxCreationKeys,
832 // For access to the pre-built transaction, see doc for trust()
833 built: BuiltCommitmentTransaction,
836 impl PartialEq for CommitmentTransaction {
837 fn eq(&self, o: &Self) -> bool {
838 let eq = self.commitment_number == o.commitment_number &&
839 self.to_broadcaster_value_sat == o.to_broadcaster_value_sat &&
840 self.to_countersignatory_value_sat == o.to_countersignatory_value_sat &&
841 self.feerate_per_kw == o.feerate_per_kw &&
842 self.htlcs == o.htlcs &&
845 debug_assert_eq!(self.built.transaction, o.built.transaction);
846 debug_assert_eq!(self.built.txid, o.built.txid);
852 /// (C-not exported) as users never need to call this directly
853 impl Writeable for Vec<HTLCOutputInCommitment> {
855 fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
856 (self.len() as u16).write(w)?;
857 for e in self.iter() {
864 /// (C-not exported) as users never need to call this directly
865 impl Readable for Vec<HTLCOutputInCommitment> {
867 fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
868 let len: u16 = Readable::read(r)?;
869 let byte_size = (len as usize)
870 .checked_mul(HTLC_OUTPUT_IN_COMMITMENT_SIZE)
871 .ok_or(DecodeError::BadLengthDescriptor)?;
872 if byte_size > MAX_BUF_SIZE {
873 return Err(DecodeError::BadLengthDescriptor);
875 let mut ret = Vec::with_capacity(len as usize);
876 for _ in 0..len { ret.push(HTLCOutputInCommitment::read(r)?); }
881 impl_writeable!(CommitmentTransaction, 0, {
883 to_broadcaster_value_sat,
884 to_countersignatory_value_sat,
891 impl CommitmentTransaction {
892 /// Construct an object of the class while assigning transaction output indices to HTLCs.
894 /// Populates HTLCOutputInCommitment.transaction_output_index in htlcs_with_aux.
896 /// The generic T allows the caller to match the HTLC output index with auxiliary data.
897 /// This auxiliary data is not stored in this object.
899 /// Only include HTLCs that are above the dust limit for the channel.
901 /// (C-not exported) due to the generic though we likely should expose a version without
902 pub fn new_with_auxiliary_htlc_data<T>(commitment_number: u64, to_broadcaster_value_sat: u64, to_countersignatory_value_sat: u64, keys: TxCreationKeys, feerate_per_kw: u32, htlcs_with_aux: &mut Vec<(HTLCOutputInCommitment, T)>, channel_parameters: &DirectedChannelTransactionParameters) -> CommitmentTransaction {
903 // Sort outputs and populate output indices while keeping track of the auxiliary data
904 let (outputs, htlcs) = Self::internal_build_outputs(&keys, to_broadcaster_value_sat, to_countersignatory_value_sat, htlcs_with_aux, channel_parameters).unwrap();
906 let (obscured_commitment_transaction_number, txins) = Self::internal_build_inputs(commitment_number, channel_parameters);
907 let transaction = Self::make_transaction(obscured_commitment_transaction_number, txins, outputs);
908 let txid = transaction.txid();
909 CommitmentTransaction {
911 to_broadcaster_value_sat,
912 to_countersignatory_value_sat,
916 built: BuiltCommitmentTransaction {
923 fn internal_rebuild_transaction(&self, keys: &TxCreationKeys, channel_parameters: &DirectedChannelTransactionParameters) -> Result<BuiltCommitmentTransaction, ()> {
924 let (obscured_commitment_transaction_number, txins) = Self::internal_build_inputs(self.commitment_number, channel_parameters);
926 let mut htlcs_with_aux = self.htlcs.iter().map(|h| (h.clone(), ())).collect();
927 let (outputs, _) = Self::internal_build_outputs(keys, self.to_broadcaster_value_sat, self.to_countersignatory_value_sat, &mut htlcs_with_aux, channel_parameters)?;
929 let transaction = Self::make_transaction(obscured_commitment_transaction_number, txins, outputs);
930 let txid = transaction.txid();
931 let built_transaction = BuiltCommitmentTransaction {
935 Ok(built_transaction)
938 fn make_transaction(obscured_commitment_transaction_number: u64, txins: Vec<TxIn>, outputs: Vec<TxOut>) -> Transaction {
941 lock_time: ((0x20 as u32) << 8 * 3) | ((obscured_commitment_transaction_number & 0xffffffu64) as u32),
947 // This is used in two cases:
948 // - initial sorting of outputs / HTLCs in the constructor, in which case T is auxiliary data the
949 // caller needs to have sorted together with the HTLCs so it can keep track of the output index
950 // - building of a bitcoin transaction during a verify() call, in which case T is just ()
951 fn internal_build_outputs<T>(keys: &TxCreationKeys, to_broadcaster_value_sat: u64, to_countersignatory_value_sat: u64, htlcs_with_aux: &mut Vec<(HTLCOutputInCommitment, T)>, channel_parameters: &DirectedChannelTransactionParameters) -> Result<(Vec<TxOut>, Vec<HTLCOutputInCommitment>), ()> {
952 let countersignatory_pubkeys = channel_parameters.countersignatory_pubkeys();
953 let contest_delay = channel_parameters.contest_delay();
955 let mut txouts: Vec<(TxOut, Option<&mut HTLCOutputInCommitment>)> = Vec::new();
957 if to_countersignatory_value_sat > 0 {
958 let script = script_for_p2wpkh(&countersignatory_pubkeys.payment_point);
961 script_pubkey: script.clone(),
962 value: to_countersignatory_value_sat,
968 if to_broadcaster_value_sat > 0 {
969 let redeem_script = get_revokeable_redeemscript(
970 &keys.revocation_key,
972 &keys.broadcaster_delayed_payment_key,
976 script_pubkey: redeem_script.to_v0_p2wsh(),
977 value: to_broadcaster_value_sat,
983 let mut htlcs = Vec::with_capacity(htlcs_with_aux.len());
984 for (htlc, _) in htlcs_with_aux {
985 let script = chan_utils::get_htlc_redeemscript(&htlc, &keys);
987 script_pubkey: script.to_v0_p2wsh(),
988 value: htlc.amount_msat / 1000,
990 txouts.push((txout, Some(htlc)));
993 // Sort output in BIP-69 order (amount, scriptPubkey). Tie-breaks based on HTLC
994 // CLTV expiration height.
995 sort_outputs(&mut txouts, |a, b| {
996 if let &Some(ref a_htlcout) = a {
997 if let &Some(ref b_htlcout) = b {
998 a_htlcout.cltv_expiry.cmp(&b_htlcout.cltv_expiry)
999 // Note that due to hash collisions, we have to have a fallback comparison
1000 // here for fuzztarget mode (otherwise at least chanmon_fail_consistency
1002 .then(a_htlcout.payment_hash.0.cmp(&b_htlcout.payment_hash.0))
1003 // For non-HTLC outputs, if they're copying our SPK we don't really care if we
1004 // close the channel due to mismatches - they're doing something dumb:
1005 } else { cmp::Ordering::Equal }
1006 } else { cmp::Ordering::Equal }
1009 let mut outputs = Vec::with_capacity(txouts.len());
1010 for (idx, out) in txouts.drain(..).enumerate() {
1011 if let Some(htlc) = out.1 {
1012 htlc.transaction_output_index = Some(idx as u32);
1013 htlcs.push(htlc.clone());
1015 outputs.push(out.0);
1017 Ok((outputs, htlcs))
1020 fn internal_build_inputs(commitment_number: u64, channel_parameters: &DirectedChannelTransactionParameters) -> (u64, Vec<TxIn>) {
1021 let broadcaster_pubkeys = channel_parameters.broadcaster_pubkeys();
1022 let countersignatory_pubkeys = channel_parameters.countersignatory_pubkeys();
1023 let commitment_transaction_number_obscure_factor = get_commitment_transaction_number_obscure_factor(
1024 &broadcaster_pubkeys.payment_point,
1025 &countersignatory_pubkeys.payment_point,
1026 channel_parameters.is_outbound(),
1029 let obscured_commitment_transaction_number =
1030 commitment_transaction_number_obscure_factor ^ (INITIAL_COMMITMENT_NUMBER - commitment_number);
1033 let mut ins: Vec<TxIn> = Vec::new();
1035 previous_output: channel_parameters.funding_outpoint(),
1036 script_sig: Script::new(),
1037 sequence: ((0x80 as u32) << 8 * 3)
1038 | ((obscured_commitment_transaction_number >> 3 * 8) as u32),
1039 witness: Vec::new(),
1043 (obscured_commitment_transaction_number, txins)
1046 /// The backwards-counting commitment number
1047 pub fn commitment_number(&self) -> u64 {
1048 self.commitment_number
1051 /// The value to be sent to the broadcaster
1052 pub fn to_broadcaster_value_sat(&self) -> u64 {
1053 self.to_broadcaster_value_sat
1056 /// The value to be sent to the counterparty
1057 pub fn to_countersignatory_value_sat(&self) -> u64 {
1058 self.to_countersignatory_value_sat
1061 /// The feerate paid per 1000-weight-unit in this commitment transaction.
1062 pub fn feerate_per_kw(&self) -> u32 {
1066 /// The non-dust HTLCs (direction, amt, height expiration, hash, transaction output index)
1067 /// which were included in this commitment transaction in output order.
1068 /// The transaction index is always populated.
1070 /// (C-not exported) as we cannot currently convert Vec references to/from C, though we should
1071 /// expose a less effecient version which creates a Vec of references in the future.
1072 pub fn htlcs(&self) -> &Vec<HTLCOutputInCommitment> {
1076 /// Trust our pre-built transaction and derived transaction creation public keys.
1078 /// Applies a wrapper which allows access to these fields.
1080 /// This should only be used if you fully trust the builder of this object. It should not
1081 /// be used by an external signer - instead use the verify function.
1082 pub fn trust(&self) -> TrustedCommitmentTransaction {
1083 TrustedCommitmentTransaction { inner: self }
1086 /// Verify our pre-built transaction and derived transaction creation public keys.
1088 /// Applies a wrapper which allows access to these fields.
1090 /// An external validating signer must call this method before signing
1091 /// or using the built transaction.
1092 pub fn verify<T: secp256k1::Signing + secp256k1::Verification>(&self, channel_parameters: &DirectedChannelTransactionParameters, broadcaster_keys: &ChannelPublicKeys, countersignatory_keys: &ChannelPublicKeys, secp_ctx: &Secp256k1<T>) -> Result<TrustedCommitmentTransaction, ()> {
1093 // This is the only field of the key cache that we trust
1094 let per_commitment_point = self.keys.per_commitment_point;
1095 let keys = TxCreationKeys::from_channel_static_keys(&per_commitment_point, broadcaster_keys, countersignatory_keys, secp_ctx).unwrap();
1096 if keys != self.keys {
1099 let tx = self.internal_rebuild_transaction(&keys, channel_parameters)?;
1100 if self.built.transaction != tx.transaction || self.built.txid != tx.txid {
1103 Ok(TrustedCommitmentTransaction { inner: self })
1107 /// A wrapper on CommitmentTransaction indicating that the derived fields (the built bitcoin
1108 /// transaction and the transaction creation keys) are trusted.
1110 /// See trust() and verify() functions on CommitmentTransaction.
1112 /// This structure implements Deref.
1113 pub struct TrustedCommitmentTransaction<'a> {
1114 inner: &'a CommitmentTransaction,
1117 impl<'a> Deref for TrustedCommitmentTransaction<'a> {
1118 type Target = CommitmentTransaction;
1120 fn deref(&self) -> &Self::Target { self.inner }
1123 impl<'a> TrustedCommitmentTransaction<'a> {
1124 /// The transaction ID of the built Bitcoin transaction
1125 pub fn txid(&self) -> Txid {
1126 self.inner.built.txid
1129 /// The pre-built Bitcoin commitment transaction
1130 pub fn built_transaction(&self) -> &BuiltCommitmentTransaction {
1134 /// The pre-calculated transaction creation public keys.
1135 pub fn keys(&self) -> &TxCreationKeys {
1139 /// Get a signature for each HTLC which was included in the commitment transaction (ie for
1140 /// which HTLCOutputInCommitment::transaction_output_index.is_some()).
1142 /// The returned Vec has one entry for each HTLC, and in the same order.
1143 pub fn get_htlc_sigs<T: secp256k1::Signing>(&self, htlc_base_key: &SecretKey, channel_parameters: &DirectedChannelTransactionParameters, secp_ctx: &Secp256k1<T>) -> Result<Vec<Signature>, ()> {
1144 let inner = self.inner;
1145 let keys = &inner.keys;
1146 let txid = inner.built.txid;
1147 let mut ret = Vec::with_capacity(inner.htlcs.len());
1148 let holder_htlc_key = derive_private_key(secp_ctx, &inner.keys.per_commitment_point, htlc_base_key).map_err(|_| ())?;
1150 for this_htlc in inner.htlcs.iter() {
1151 assert!(this_htlc.transaction_output_index.is_some());
1152 let htlc_tx = build_htlc_transaction(&txid, inner.feerate_per_kw, channel_parameters.contest_delay(), &this_htlc, &keys.broadcaster_delayed_payment_key, &keys.revocation_key);
1154 let htlc_redeemscript = get_htlc_redeemscript_with_explicit_keys(&this_htlc, &keys.broadcaster_htlc_key, &keys.countersignatory_htlc_key, &keys.revocation_key);
1156 let sighash = hash_to_message!(&bip143::SigHashCache::new(&htlc_tx).signature_hash(0, &htlc_redeemscript, this_htlc.amount_msat / 1000, SigHashType::All)[..]);
1157 ret.push(secp_ctx.sign(&sighash, &holder_htlc_key));
1162 /// Gets a signed HTLC transaction given a preimage (for !htlc.offered) and the holder HTLC transaction signature.
1163 pub(crate) fn get_signed_htlc_tx(&self, channel_parameters: &DirectedChannelTransactionParameters, htlc_index: usize, counterparty_signature: &Signature, signature: &Signature, preimage: &Option<PaymentPreimage>) -> Transaction {
1164 let inner = self.inner;
1165 let keys = &inner.keys;
1166 let txid = inner.built.txid;
1167 let this_htlc = &inner.htlcs[htlc_index];
1168 assert!(this_htlc.transaction_output_index.is_some());
1169 // if we don't have preimage for an HTLC-Success, we can't generate an HTLC transaction.
1170 if !this_htlc.offered && preimage.is_none() { unreachable!(); }
1171 // Further, we should never be provided the preimage for an HTLC-Timeout transaction.
1172 if this_htlc.offered && preimage.is_some() { unreachable!(); }
1174 let mut htlc_tx = build_htlc_transaction(&txid, inner.feerate_per_kw, channel_parameters.contest_delay(), &this_htlc, &keys.broadcaster_delayed_payment_key, &keys.revocation_key);
1176 let htlc_redeemscript = get_htlc_redeemscript_with_explicit_keys(&this_htlc, &keys.broadcaster_htlc_key, &keys.countersignatory_htlc_key, &keys.revocation_key);
1178 // First push the multisig dummy, note that due to BIP147 (NULLDUMMY) it must be a zero-length element.
1179 htlc_tx.input[0].witness.push(Vec::new());
1181 htlc_tx.input[0].witness.push(counterparty_signature.serialize_der().to_vec());
1182 htlc_tx.input[0].witness.push(signature.serialize_der().to_vec());
1183 htlc_tx.input[0].witness[1].push(SigHashType::All as u8);
1184 htlc_tx.input[0].witness[2].push(SigHashType::All as u8);
1186 if this_htlc.offered {
1187 // Due to BIP146 (MINIMALIF) this must be a zero-length element to relay.
1188 htlc_tx.input[0].witness.push(Vec::new());
1190 htlc_tx.input[0].witness.push(preimage.unwrap().0.to_vec());
1193 htlc_tx.input[0].witness.push(htlc_redeemscript.as_bytes().to_vec());
1198 /// Get the transaction number obscure factor
1199 pub fn get_commitment_transaction_number_obscure_factor(
1200 broadcaster_payment_basepoint: &PublicKey,
1201 countersignatory_payment_basepoint: &PublicKey,
1202 outbound_from_broadcaster: bool,
1204 let mut sha = Sha256::engine();
1206 if outbound_from_broadcaster {
1207 sha.input(&broadcaster_payment_basepoint.serialize());
1208 sha.input(&countersignatory_payment_basepoint.serialize());
1210 sha.input(&countersignatory_payment_basepoint.serialize());
1211 sha.input(&broadcaster_payment_basepoint.serialize());
1213 let res = Sha256::from_engine(sha).into_inner();
1215 ((res[26] as u64) << 5 * 8)
1216 | ((res[27] as u64) << 4 * 8)
1217 | ((res[28] as u64) << 3 * 8)
1218 | ((res[29] as u64) << 2 * 8)
1219 | ((res[30] as u64) << 1 * 8)
1220 | ((res[31] as u64) << 0 * 8)
1223 fn script_for_p2wpkh(key: &PublicKey) -> Script {
1224 Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0)
1225 .push_slice(&WPubkeyHash::hash(&key.serialize())[..])
1231 use super::CounterpartyCommitmentSecrets;
1235 fn test_per_commitment_storage() {
1236 // Test vectors from BOLT 3:
1237 let mut secrets: Vec<[u8; 32]> = Vec::new();
1240 macro_rules! test_secrets {
1242 let mut idx = 281474976710655;
1243 for secret in secrets.iter() {
1244 assert_eq!(monitor.get_secret(idx).unwrap(), *secret);
1247 assert_eq!(monitor.get_min_seen_secret(), idx + 1);
1248 assert!(monitor.get_secret(idx).is_none());
1253 // insert_secret correct sequence
1254 monitor = CounterpartyCommitmentSecrets::new();
1257 secrets.push([0; 32]);
1258 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1259 monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1262 secrets.push([0; 32]);
1263 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1264 monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1267 secrets.push([0; 32]);
1268 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1269 monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1272 secrets.push([0; 32]);
1273 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1274 monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
1277 secrets.push([0; 32]);
1278 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
1279 monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
1282 secrets.push([0; 32]);
1283 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
1284 monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
1287 secrets.push([0; 32]);
1288 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
1289 monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
1292 secrets.push([0; 32]);
1293 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
1294 monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap();
1299 // insert_secret #1 incorrect
1300 monitor = CounterpartyCommitmentSecrets::new();
1303 secrets.push([0; 32]);
1304 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
1305 monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1308 secrets.push([0; 32]);
1309 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1310 assert!(monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).is_err());
1314 // insert_secret #2 incorrect (#1 derived from incorrect)
1315 monitor = CounterpartyCommitmentSecrets::new();
1318 secrets.push([0; 32]);
1319 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
1320 monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1323 secrets.push([0; 32]);
1324 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("dddc3a8d14fddf2b68fa8c7fbad2748274937479dd0f8930d5ebb4ab6bd866a3").unwrap());
1325 monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1328 secrets.push([0; 32]);
1329 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1330 monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1333 secrets.push([0; 32]);
1334 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1335 assert!(monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).is_err());
1339 // insert_secret #3 incorrect
1340 monitor = CounterpartyCommitmentSecrets::new();
1343 secrets.push([0; 32]);
1344 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1345 monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1348 secrets.push([0; 32]);
1349 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1350 monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1353 secrets.push([0; 32]);
1354 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c51a18b13e8527e579ec56365482c62f180b7d5760b46e9477dae59e87ed423a").unwrap());
1355 monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1358 secrets.push([0; 32]);
1359 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1360 assert!(monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).is_err());
1364 // insert_secret #4 incorrect (1,2,3 derived from incorrect)
1365 monitor = CounterpartyCommitmentSecrets::new();
1368 secrets.push([0; 32]);
1369 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
1370 monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1373 secrets.push([0; 32]);
1374 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("dddc3a8d14fddf2b68fa8c7fbad2748274937479dd0f8930d5ebb4ab6bd866a3").unwrap());
1375 monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1378 secrets.push([0; 32]);
1379 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c51a18b13e8527e579ec56365482c62f180b7d5760b46e9477dae59e87ed423a").unwrap());
1380 monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1383 secrets.push([0; 32]);
1384 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("ba65d7b0ef55a3ba300d4e87af29868f394f8f138d78a7011669c79b37b936f4").unwrap());
1385 monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
1388 secrets.push([0; 32]);
1389 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
1390 monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
1393 secrets.push([0; 32]);
1394 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
1395 monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
1398 secrets.push([0; 32]);
1399 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
1400 monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
1403 secrets.push([0; 32]);
1404 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
1405 assert!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).is_err());
1409 // insert_secret #5 incorrect
1410 monitor = CounterpartyCommitmentSecrets::new();
1413 secrets.push([0; 32]);
1414 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1415 monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1418 secrets.push([0; 32]);
1419 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1420 monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1423 secrets.push([0; 32]);
1424 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1425 monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1428 secrets.push([0; 32]);
1429 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1430 monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
1433 secrets.push([0; 32]);
1434 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("631373ad5f9ef654bb3dade742d09504c567edd24320d2fcd68e3cc47e2ff6a6").unwrap());
1435 monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
1438 secrets.push([0; 32]);
1439 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
1440 assert!(monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).is_err());
1444 // insert_secret #6 incorrect (5 derived from incorrect)
1445 monitor = CounterpartyCommitmentSecrets::new();
1448 secrets.push([0; 32]);
1449 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1450 monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1453 secrets.push([0; 32]);
1454 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1455 monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1458 secrets.push([0; 32]);
1459 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1460 monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1463 secrets.push([0; 32]);
1464 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1465 monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
1468 secrets.push([0; 32]);
1469 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("631373ad5f9ef654bb3dade742d09504c567edd24320d2fcd68e3cc47e2ff6a6").unwrap());
1470 monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
1473 secrets.push([0; 32]);
1474 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("b7e76a83668bde38b373970155c868a653304308f9896692f904a23731224bb1").unwrap());
1475 monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
1478 secrets.push([0; 32]);
1479 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
1480 monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
1483 secrets.push([0; 32]);
1484 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
1485 assert!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).is_err());
1489 // insert_secret #7 incorrect
1490 monitor = CounterpartyCommitmentSecrets::new();
1493 secrets.push([0; 32]);
1494 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1495 monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1498 secrets.push([0; 32]);
1499 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1500 monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1503 secrets.push([0; 32]);
1504 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1505 monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1508 secrets.push([0; 32]);
1509 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1510 monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
1513 secrets.push([0; 32]);
1514 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
1515 monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
1518 secrets.push([0; 32]);
1519 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
1520 monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
1523 secrets.push([0; 32]);
1524 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("e7971de736e01da8ed58b94c2fc216cb1dca9e326f3a96e7194fe8ea8af6c0a3").unwrap());
1525 monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
1528 secrets.push([0; 32]);
1529 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
1530 assert!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).is_err());
1534 // insert_secret #8 incorrect
1535 monitor = CounterpartyCommitmentSecrets::new();
1538 secrets.push([0; 32]);
1539 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1540 monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1543 secrets.push([0; 32]);
1544 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1545 monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1548 secrets.push([0; 32]);
1549 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1550 monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1553 secrets.push([0; 32]);
1554 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1555 monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
1558 secrets.push([0; 32]);
1559 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
1560 monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
1563 secrets.push([0; 32]);
1564 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
1565 monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
1568 secrets.push([0; 32]);
1569 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
1570 monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
1573 secrets.push([0; 32]);
1574 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a7efbc61aac46d34f77778bac22c8a20c6a46ca460addc49009bda875ec88fa4").unwrap());
1575 assert!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).is_err());