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 the traits on [`crate::sign`] by hand.
13 use bitcoin::blockdata::script::{Script,Builder};
14 use bitcoin::blockdata::opcodes;
15 use bitcoin::blockdata::transaction::{TxIn,TxOut,OutPoint,Transaction, EcdsaSighashType};
16 use bitcoin::util::sighash;
17 use bitcoin::util::address::Payload;
19 use bitcoin::hashes::{Hash, HashEngine};
20 use bitcoin::hashes::sha256::Hash as Sha256;
21 use bitcoin::hashes::ripemd160::Hash as Ripemd160;
22 use bitcoin::hash_types::{Txid, PubkeyHash, WPubkeyHash};
24 use crate::chain::chaininterface::fee_for_weight;
25 use crate::chain::package::WEIGHT_REVOKED_OUTPUT;
26 use crate::sign::EntropySource;
27 use crate::ln::{PaymentHash, PaymentPreimage};
28 use crate::ln::msgs::DecodeError;
29 use crate::util::ser::{Readable, RequiredWrapper, Writeable, Writer};
30 use crate::util::transaction_utils;
32 use bitcoin::secp256k1::{SecretKey, PublicKey, Scalar};
33 use bitcoin::secp256k1::{Secp256k1, ecdsa::Signature, Message};
34 use bitcoin::{PackedLockTime, secp256k1, Sequence, Witness};
35 use bitcoin::PublicKey as BitcoinPublicKey;
38 use crate::prelude::*;
40 use crate::ln::chan_utils;
41 use crate::util::transaction_utils::sort_outputs;
42 use crate::ln::channel::{INITIAL_COMMITMENT_NUMBER, ANCHOR_OUTPUT_VALUE_SATOSHI};
45 use crate::ln::features::ChannelTypeFeatures;
46 use crate::util::crypto::{sign, sign_with_aux_rand};
48 /// Maximum number of one-way in-flight HTLC (protocol-level value).
49 pub const MAX_HTLCS: u16 = 483;
50 /// The weight of a BIP141 witnessScript for a BOLT3's "offered HTLC output" on a commitment transaction, non-anchor variant.
51 pub const OFFERED_HTLC_SCRIPT_WEIGHT: usize = 133;
52 /// The weight of a BIP141 witnessScript for a BOLT3's "offered HTLC output" on a commitment transaction, anchor variant.
53 pub const OFFERED_HTLC_SCRIPT_WEIGHT_ANCHORS: usize = 136;
55 /// The weight of a BIP141 witnessScript for a BOLT3's "received HTLC output" can vary in function of its CLTV argument value.
56 /// We define a range that encompasses both its non-anchors and anchors variants.
57 pub(crate) const MIN_ACCEPTED_HTLC_SCRIPT_WEIGHT: usize = 136;
58 /// The weight of a BIP141 witnessScript for a BOLT3's "received HTLC output" can vary in function of its CLTV argument value.
59 /// We define a range that encompasses both its non-anchors and anchors variants.
60 /// This is the maximum post-anchor value.
61 pub const MAX_ACCEPTED_HTLC_SCRIPT_WEIGHT: usize = 143;
63 /// The upper bound weight of an anchor input.
64 pub const ANCHOR_INPUT_WITNESS_WEIGHT: u64 = 116;
65 /// The upper bound weight of an HTLC timeout input from a commitment transaction with anchor
67 pub const HTLC_TIMEOUT_INPUT_ANCHOR_WITNESS_WEIGHT: u64 = 288;
68 /// The upper bound weight of an HTLC success input from a commitment transaction with anchor
70 pub const HTLC_SUCCESS_INPUT_ANCHOR_WITNESS_WEIGHT: u64 = 327;
72 /// Gets the weight for an HTLC-Success transaction.
74 pub fn htlc_success_tx_weight(channel_type_features: &ChannelTypeFeatures) -> u64 {
75 const HTLC_SUCCESS_TX_WEIGHT: u64 = 703;
76 const HTLC_SUCCESS_ANCHOR_TX_WEIGHT: u64 = 706;
77 if channel_type_features.supports_anchors_zero_fee_htlc_tx() { HTLC_SUCCESS_ANCHOR_TX_WEIGHT } else { HTLC_SUCCESS_TX_WEIGHT }
80 /// Gets the weight for an HTLC-Timeout transaction.
82 pub fn htlc_timeout_tx_weight(channel_type_features: &ChannelTypeFeatures) -> u64 {
83 const HTLC_TIMEOUT_TX_WEIGHT: u64 = 663;
84 const HTLC_TIMEOUT_ANCHOR_TX_WEIGHT: u64 = 666;
85 if channel_type_features.supports_anchors_zero_fee_htlc_tx() { HTLC_TIMEOUT_ANCHOR_TX_WEIGHT } else { HTLC_TIMEOUT_TX_WEIGHT }
88 /// Describes the type of HTLC claim as determined by analyzing the witness.
89 #[derive(PartialEq, Eq)]
91 /// Claims an offered output on a commitment transaction through the timeout path.
93 /// Claims an offered output on a commitment transaction through the success path.
95 /// Claims an accepted output on a commitment transaction through the timeout path.
97 /// Claims an accepted output on a commitment transaction through the success path.
99 /// Claims an offered/accepted output on a commitment transaction through the revocation path.
104 /// Check if a given input witness attempts to claim a HTLC.
105 pub fn from_witness(witness: &Witness) -> Option<Self> {
106 debug_assert_eq!(OFFERED_HTLC_SCRIPT_WEIGHT_ANCHORS, MIN_ACCEPTED_HTLC_SCRIPT_WEIGHT);
107 if witness.len() < 2 {
110 let witness_script = witness.last().unwrap();
111 let second_to_last = witness.second_to_last().unwrap();
112 if witness_script.len() == OFFERED_HTLC_SCRIPT_WEIGHT {
113 if witness.len() == 3 && second_to_last.len() == 33 {
114 // <revocation sig> <revocationpubkey> <witness_script>
115 Some(Self::Revocation)
116 } else if witness.len() == 3 && second_to_last.len() == 32 {
117 // <remotehtlcsig> <payment_preimage> <witness_script>
118 Some(Self::OfferedPreimage)
119 } else if witness.len() == 5 && second_to_last.len() == 0 {
120 // 0 <remotehtlcsig> <localhtlcsig> <> <witness_script>
121 Some(Self::OfferedTimeout)
125 } else if witness_script.len() == OFFERED_HTLC_SCRIPT_WEIGHT_ANCHORS {
126 // It's possible for the weight of `offered_htlc_script` and `accepted_htlc_script` to
127 // match so we check for both here.
128 if witness.len() == 3 && second_to_last.len() == 33 {
129 // <revocation sig> <revocationpubkey> <witness_script>
130 Some(Self::Revocation)
131 } else if witness.len() == 3 && second_to_last.len() == 32 {
132 // <remotehtlcsig> <payment_preimage> <witness_script>
133 Some(Self::OfferedPreimage)
134 } else if witness.len() == 5 && second_to_last.len() == 0 {
135 // 0 <remotehtlcsig> <localhtlcsig> <> <witness_script>
136 Some(Self::OfferedTimeout)
137 } else if witness.len() == 3 && second_to_last.len() == 0 {
138 // <remotehtlcsig> <> <witness_script>
139 Some(Self::AcceptedTimeout)
140 } else if witness.len() == 5 && second_to_last.len() == 32 {
141 // 0 <remotehtlcsig> <localhtlcsig> <payment_preimage> <witness_script>
142 Some(Self::AcceptedPreimage)
146 } else if witness_script.len() > MIN_ACCEPTED_HTLC_SCRIPT_WEIGHT &&
147 witness_script.len() <= MAX_ACCEPTED_HTLC_SCRIPT_WEIGHT {
148 // Handle remaining range of ACCEPTED_HTLC_SCRIPT_WEIGHT.
149 if witness.len() == 3 && second_to_last.len() == 33 {
150 // <revocation sig> <revocationpubkey> <witness_script>
151 Some(Self::Revocation)
152 } else if witness.len() == 3 && second_to_last.len() == 0 {
153 // <remotehtlcsig> <> <witness_script>
154 Some(Self::AcceptedTimeout)
155 } else if witness.len() == 5 && second_to_last.len() == 32 {
156 // 0 <remotehtlcsig> <localhtlcsig> <payment_preimage> <witness_script>
157 Some(Self::AcceptedPreimage)
167 // Various functions for key derivation and transaction creation for use within channels. Primarily
168 // used in Channel and ChannelMonitor.
170 /// Build the commitment secret from the seed and the commitment number
171 pub fn build_commitment_secret(commitment_seed: &[u8; 32], idx: u64) -> [u8; 32] {
172 let mut res: [u8; 32] = commitment_seed.clone();
175 if idx & (1 << bitpos) == (1 << bitpos) {
176 res[bitpos / 8] ^= 1 << (bitpos & 7);
177 res = Sha256::hash(&res).into_inner();
183 /// Build a closing transaction
184 pub fn build_closing_transaction(to_holder_value_sat: u64, to_counterparty_value_sat: u64, to_holder_script: Script, to_counterparty_script: Script, funding_outpoint: OutPoint) -> Transaction {
186 let mut ins: Vec<TxIn> = Vec::new();
188 previous_output: funding_outpoint,
189 script_sig: Script::new(),
190 sequence: Sequence::MAX,
191 witness: Witness::new(),
196 let mut txouts: Vec<(TxOut, ())> = Vec::new();
198 if to_counterparty_value_sat > 0 {
200 script_pubkey: to_counterparty_script,
201 value: to_counterparty_value_sat
205 if to_holder_value_sat > 0 {
207 script_pubkey: to_holder_script,
208 value: to_holder_value_sat
212 transaction_utils::sort_outputs(&mut txouts, |_, _| { cmp::Ordering::Equal }); // Ordering doesnt matter if they used our pubkey...
214 let mut outputs: Vec<TxOut> = Vec::new();
215 for out in txouts.drain(..) {
221 lock_time: PackedLockTime::ZERO,
227 /// Implements the per-commitment secret storage scheme from
228 /// [BOLT 3](https://github.com/lightning/bolts/blob/dcbf8583976df087c79c3ce0b535311212e6812d/03-transactions.md#efficient-per-commitment-secret-storage).
230 /// Allows us to keep track of all of the revocation secrets of our counterparty in just 50*32 bytes
233 pub struct CounterpartyCommitmentSecrets {
234 old_secrets: [([u8; 32], u64); 49],
237 impl Eq for CounterpartyCommitmentSecrets {}
238 impl PartialEq for CounterpartyCommitmentSecrets {
239 fn eq(&self, other: &Self) -> bool {
240 for (&(ref secret, ref idx), &(ref o_secret, ref o_idx)) in self.old_secrets.iter().zip(other.old_secrets.iter()) {
241 if secret != o_secret || idx != o_idx {
249 impl CounterpartyCommitmentSecrets {
250 /// Creates a new empty `CounterpartyCommitmentSecrets` structure.
251 pub fn new() -> Self {
252 Self { old_secrets: [([0; 32], 1 << 48); 49], }
256 fn place_secret(idx: u64) -> u8 {
258 if idx & (1 << i) == (1 << i) {
265 /// Returns the minimum index of all stored secrets. Note that indexes start
266 /// at 1 << 48 and get decremented by one for each new secret.
267 pub fn get_min_seen_secret(&self) -> u64 {
268 //TODO This can be optimized?
269 let mut min = 1 << 48;
270 for &(_, idx) in self.old_secrets.iter() {
279 fn derive_secret(secret: [u8; 32], bits: u8, idx: u64) -> [u8; 32] {
280 let mut res: [u8; 32] = secret;
282 let bitpos = bits - 1 - i;
283 if idx & (1 << bitpos) == (1 << bitpos) {
284 res[(bitpos / 8) as usize] ^= 1 << (bitpos & 7);
285 res = Sha256::hash(&res).into_inner();
291 /// Inserts the `secret` at `idx`. Returns `Ok(())` if the secret
292 /// was generated in accordance with BOLT 3 and is consistent with previous secrets.
293 pub fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), ()> {
294 let pos = Self::place_secret(idx);
296 let (old_secret, old_idx) = self.old_secrets[i as usize];
297 if Self::derive_secret(secret, pos, old_idx) != old_secret {
301 if self.get_min_seen_secret() <= idx {
304 self.old_secrets[pos as usize] = (secret, idx);
308 /// Returns the secret at `idx`.
309 /// Returns `None` if `idx` is < [`CounterpartyCommitmentSecrets::get_min_seen_secret`].
310 pub fn get_secret(&self, idx: u64) -> Option<[u8; 32]> {
311 for i in 0..self.old_secrets.len() {
312 if (idx & (!((1 << i) - 1))) == self.old_secrets[i].1 {
313 return Some(Self::derive_secret(self.old_secrets[i].0, i as u8, idx))
316 assert!(idx < self.get_min_seen_secret());
321 impl Writeable for CounterpartyCommitmentSecrets {
322 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
323 for &(ref secret, ref idx) in self.old_secrets.iter() {
324 writer.write_all(secret)?;
325 writer.write_all(&idx.to_be_bytes())?;
327 write_tlv_fields!(writer, {});
331 impl Readable for CounterpartyCommitmentSecrets {
332 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
333 let mut old_secrets = [([0; 32], 1 << 48); 49];
334 for &mut (ref mut secret, ref mut idx) in old_secrets.iter_mut() {
335 *secret = Readable::read(reader)?;
336 *idx = Readable::read(reader)?;
338 read_tlv_fields!(reader, {});
339 Ok(Self { old_secrets })
343 /// Derives a per-commitment-transaction private key (eg an htlc key or delayed_payment key)
344 /// from the base secret and the per_commitment_point.
345 pub fn derive_private_key<T: secp256k1::Signing>(secp_ctx: &Secp256k1<T>, per_commitment_point: &PublicKey, base_secret: &SecretKey) -> SecretKey {
346 let mut sha = Sha256::engine();
347 sha.input(&per_commitment_point.serialize());
348 sha.input(&PublicKey::from_secret_key(&secp_ctx, &base_secret).serialize());
349 let res = Sha256::from_engine(sha).into_inner();
351 base_secret.clone().add_tweak(&Scalar::from_be_bytes(res).unwrap())
352 .expect("Addition only fails if the tweak is the inverse of the key. This is not possible when the tweak contains the hash of the key.")
355 /// Derives a per-commitment-transaction public key (eg an htlc key or a delayed_payment key)
356 /// from the base point and the per_commitment_key. This is the public equivalent of
357 /// derive_private_key - using only public keys to derive a public key instead of private keys.
358 pub fn derive_public_key<T: secp256k1::Signing>(secp_ctx: &Secp256k1<T>, per_commitment_point: &PublicKey, base_point: &PublicKey) -> PublicKey {
359 let mut sha = Sha256::engine();
360 sha.input(&per_commitment_point.serialize());
361 sha.input(&base_point.serialize());
362 let res = Sha256::from_engine(sha).into_inner();
364 let hashkey = PublicKey::from_secret_key(&secp_ctx,
365 &SecretKey::from_slice(&res).expect("Hashes should always be valid keys unless SHA-256 is broken"));
366 base_point.combine(&hashkey)
367 .expect("Addition only fails if the tweak is the inverse of the key. This is not possible when the tweak contains the hash of the key.")
370 /// Derives a per-commitment-transaction revocation key from its constituent parts.
372 /// Only the cheating participant owns a valid witness to propagate a revoked
373 /// commitment transaction, thus per_commitment_secret always come from cheater
374 /// and revocation_base_secret always come from punisher, which is the broadcaster
375 /// of the transaction spending with this key knowledge.
376 pub fn derive_private_revocation_key<T: secp256k1::Signing>(secp_ctx: &Secp256k1<T>,
377 per_commitment_secret: &SecretKey, countersignatory_revocation_base_secret: &SecretKey)
379 let countersignatory_revocation_base_point = PublicKey::from_secret_key(&secp_ctx, &countersignatory_revocation_base_secret);
380 let per_commitment_point = PublicKey::from_secret_key(&secp_ctx, &per_commitment_secret);
382 let rev_append_commit_hash_key = {
383 let mut sha = Sha256::engine();
384 sha.input(&countersignatory_revocation_base_point.serialize());
385 sha.input(&per_commitment_point.serialize());
387 Sha256::from_engine(sha).into_inner()
389 let commit_append_rev_hash_key = {
390 let mut sha = Sha256::engine();
391 sha.input(&per_commitment_point.serialize());
392 sha.input(&countersignatory_revocation_base_point.serialize());
394 Sha256::from_engine(sha).into_inner()
397 let countersignatory_contrib = countersignatory_revocation_base_secret.clone().mul_tweak(&Scalar::from_be_bytes(rev_append_commit_hash_key).unwrap())
398 .expect("Multiplying a secret key by a hash is expected to never fail per secp256k1 docs");
399 let broadcaster_contrib = per_commitment_secret.clone().mul_tweak(&Scalar::from_be_bytes(commit_append_rev_hash_key).unwrap())
400 .expect("Multiplying a secret key by a hash is expected to never fail per secp256k1 docs");
401 countersignatory_contrib.add_tweak(&Scalar::from_be_bytes(broadcaster_contrib.secret_bytes()).unwrap())
402 .expect("Addition only fails if the tweak is the inverse of the key. This is not possible when the tweak commits to the key.")
405 /// Derives a per-commitment-transaction revocation public key from its constituent parts. This is
406 /// the public equivalend of derive_private_revocation_key - using only public keys to derive a
407 /// public key instead of private keys.
409 /// Only the cheating participant owns a valid witness to propagate a revoked
410 /// commitment transaction, thus per_commitment_point always come from cheater
411 /// and revocation_base_point always come from punisher, which is the broadcaster
412 /// of the transaction spending with this key knowledge.
414 /// Note that this is infallible iff we trust that at least one of the two input keys are randomly
415 /// generated (ie our own).
416 pub fn derive_public_revocation_key<T: secp256k1::Verification>(secp_ctx: &Secp256k1<T>,
417 per_commitment_point: &PublicKey, countersignatory_revocation_base_point: &PublicKey)
419 let rev_append_commit_hash_key = {
420 let mut sha = Sha256::engine();
421 sha.input(&countersignatory_revocation_base_point.serialize());
422 sha.input(&per_commitment_point.serialize());
424 Sha256::from_engine(sha).into_inner()
426 let commit_append_rev_hash_key = {
427 let mut sha = Sha256::engine();
428 sha.input(&per_commitment_point.serialize());
429 sha.input(&countersignatory_revocation_base_point.serialize());
431 Sha256::from_engine(sha).into_inner()
434 let countersignatory_contrib = countersignatory_revocation_base_point.clone().mul_tweak(&secp_ctx, &Scalar::from_be_bytes(rev_append_commit_hash_key).unwrap())
435 .expect("Multiplying a valid public key by a hash is expected to never fail per secp256k1 docs");
436 let broadcaster_contrib = per_commitment_point.clone().mul_tweak(&secp_ctx, &Scalar::from_be_bytes(commit_append_rev_hash_key).unwrap())
437 .expect("Multiplying a valid public key by a hash is expected to never fail per secp256k1 docs");
438 countersignatory_contrib.combine(&broadcaster_contrib)
439 .expect("Addition only fails if the tweak is the inverse of the key. This is not possible when the tweak commits to the key.")
442 /// The set of public keys which are used in the creation of one commitment transaction.
443 /// These are derived from the channel base keys and per-commitment data.
445 /// A broadcaster key is provided from potential broadcaster of the computed transaction.
446 /// A countersignatory key is coming from a protocol participant unable to broadcast the
449 /// These keys are assumed to be good, either because the code derived them from
450 /// channel basepoints via the new function, or they were obtained via
451 /// CommitmentTransaction.trust().keys() because we trusted the source of the
452 /// pre-calculated keys.
453 #[derive(PartialEq, Eq, Clone, Debug)]
454 pub struct TxCreationKeys {
455 /// The broadcaster's per-commitment public key which was used to derive the other keys.
456 pub per_commitment_point: PublicKey,
457 /// The revocation key which is used to allow the broadcaster of the commitment
458 /// transaction to provide their counterparty the ability to punish them if they broadcast
460 pub revocation_key: PublicKey,
461 /// Broadcaster's HTLC Key
462 pub broadcaster_htlc_key: PublicKey,
463 /// Countersignatory's HTLC Key
464 pub countersignatory_htlc_key: PublicKey,
465 /// Broadcaster's Payment Key (which isn't allowed to be spent from for some delay)
466 pub broadcaster_delayed_payment_key: PublicKey,
469 impl_writeable_tlv_based!(TxCreationKeys, {
470 (0, per_commitment_point, required),
471 (2, revocation_key, required),
472 (4, broadcaster_htlc_key, required),
473 (6, countersignatory_htlc_key, required),
474 (8, broadcaster_delayed_payment_key, required),
477 /// One counterparty's public keys which do not change over the life of a channel.
478 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
479 pub struct ChannelPublicKeys {
480 /// The public key which is used to sign all commitment transactions, as it appears in the
481 /// on-chain channel lock-in 2-of-2 multisig output.
482 pub funding_pubkey: PublicKey,
483 /// The base point which is used (with derive_public_revocation_key) to derive per-commitment
484 /// revocation keys. This is combined with the per-commitment-secret generated by the
485 /// counterparty to create a secret which the counterparty can reveal to revoke previous
487 pub revocation_basepoint: PublicKey,
488 /// The public key on which the non-broadcaster (ie the countersignatory) receives an immediately
489 /// spendable primary channel balance on the broadcaster's commitment transaction. This key is
490 /// static across every commitment transaction.
491 pub payment_point: PublicKey,
492 /// The base point which is used (with derive_public_key) to derive a per-commitment payment
493 /// public key which receives non-HTLC-encumbered funds which are only available for spending
494 /// after some delay (or can be claimed via the revocation path).
495 pub delayed_payment_basepoint: PublicKey,
496 /// The base point which is used (with derive_public_key) to derive a per-commitment public key
497 /// which is used to encumber HTLC-in-flight outputs.
498 pub htlc_basepoint: PublicKey,
501 impl_writeable_tlv_based!(ChannelPublicKeys, {
502 (0, funding_pubkey, required),
503 (2, revocation_basepoint, required),
504 (4, payment_point, required),
505 (6, delayed_payment_basepoint, required),
506 (8, htlc_basepoint, required),
509 impl TxCreationKeys {
510 /// Create per-state keys from channel base points and the per-commitment point.
511 /// Key set is asymmetric and can't be used as part of counter-signatory set of transactions.
512 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) -> TxCreationKeys {
514 per_commitment_point: per_commitment_point.clone(),
515 revocation_key: derive_public_revocation_key(&secp_ctx, &per_commitment_point, &countersignatory_revocation_base),
516 broadcaster_htlc_key: derive_public_key(&secp_ctx, &per_commitment_point, &broadcaster_htlc_base),
517 countersignatory_htlc_key: derive_public_key(&secp_ctx, &per_commitment_point, &countersignatory_htlc_base),
518 broadcaster_delayed_payment_key: derive_public_key(&secp_ctx, &per_commitment_point, &broadcaster_delayed_payment_base),
522 /// Generate per-state keys from channel static keys.
523 /// Key set is asymmetric and can't be used as part of counter-signatory set of transactions.
524 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>) -> TxCreationKeys {
525 TxCreationKeys::derive_new(
527 &per_commitment_point,
528 &broadcaster_keys.delayed_payment_basepoint,
529 &broadcaster_keys.htlc_basepoint,
530 &countersignatory_keys.revocation_basepoint,
531 &countersignatory_keys.htlc_basepoint,
536 /// The maximum length of a script returned by get_revokeable_redeemscript.
537 // Calculated as 6 bytes of opcodes, 1 byte push plus 2 bytes for contest_delay, and two public
538 // keys of 33 bytes (+ 1 push).
539 pub const REVOKEABLE_REDEEMSCRIPT_MAX_LENGTH: usize = 6 + 3 + 34*2;
541 /// A script either spendable by the revocation
542 /// key or the broadcaster_delayed_payment_key and satisfying the relative-locktime OP_CSV constrain.
543 /// Encumbering a `to_holder` output on a commitment transaction or 2nd-stage HTLC transactions.
544 pub fn get_revokeable_redeemscript(revocation_key: &PublicKey, contest_delay: u16, broadcaster_delayed_payment_key: &PublicKey) -> Script {
545 let res = Builder::new().push_opcode(opcodes::all::OP_IF)
546 .push_slice(&revocation_key.serialize())
547 .push_opcode(opcodes::all::OP_ELSE)
548 .push_int(contest_delay as i64)
549 .push_opcode(opcodes::all::OP_CSV)
550 .push_opcode(opcodes::all::OP_DROP)
551 .push_slice(&broadcaster_delayed_payment_key.serialize())
552 .push_opcode(opcodes::all::OP_ENDIF)
553 .push_opcode(opcodes::all::OP_CHECKSIG)
555 debug_assert!(res.len() <= REVOKEABLE_REDEEMSCRIPT_MAX_LENGTH);
559 /// Returns the script for the counterparty's output on a holder's commitment transaction based on
560 /// the channel type.
561 pub fn get_counterparty_payment_script(channel_type_features: &ChannelTypeFeatures, payment_key: &PublicKey) -> Script {
562 if channel_type_features.supports_anchors_zero_fee_htlc_tx() {
563 get_to_countersignatory_with_anchors_redeemscript(payment_key).to_v0_p2wsh()
565 Script::new_v0_p2wpkh(&WPubkeyHash::hash(&payment_key.serialize()))
569 /// Information about an HTLC as it appears in a commitment transaction
570 #[derive(Clone, Debug, PartialEq, Eq)]
571 pub struct HTLCOutputInCommitment {
572 /// Whether the HTLC was "offered" (ie outbound in relation to this commitment transaction).
573 /// Note that this is not the same as whether it is ountbound *from us*. To determine that you
574 /// need to compare this value to whether the commitment transaction in question is that of
575 /// the counterparty or our own.
577 /// The value, in msat, of the HTLC. The value as it appears in the commitment transaction is
578 /// this divided by 1000.
579 pub amount_msat: u64,
580 /// The CLTV lock-time at which this HTLC expires.
581 pub cltv_expiry: u32,
582 /// The hash of the preimage which unlocks this HTLC.
583 pub payment_hash: PaymentHash,
584 /// The position within the commitment transactions' outputs. This may be None if the value is
585 /// below the dust limit (in which case no output appears in the commitment transaction and the
586 /// value is spent to additional transaction fees).
587 pub transaction_output_index: Option<u32>,
590 impl_writeable_tlv_based!(HTLCOutputInCommitment, {
591 (0, offered, required),
592 (2, amount_msat, required),
593 (4, cltv_expiry, required),
594 (6, payment_hash, required),
595 (8, transaction_output_index, option),
599 pub(crate) fn get_htlc_redeemscript_with_explicit_keys(htlc: &HTLCOutputInCommitment, channel_type_features: &ChannelTypeFeatures, broadcaster_htlc_key: &PublicKey, countersignatory_htlc_key: &PublicKey, revocation_key: &PublicKey) -> Script {
600 let payment_hash160 = Ripemd160::hash(&htlc.payment_hash.0[..]).into_inner();
602 let mut bldr = Builder::new().push_opcode(opcodes::all::OP_DUP)
603 .push_opcode(opcodes::all::OP_HASH160)
604 .push_slice(&PubkeyHash::hash(&revocation_key.serialize())[..])
605 .push_opcode(opcodes::all::OP_EQUAL)
606 .push_opcode(opcodes::all::OP_IF)
607 .push_opcode(opcodes::all::OP_CHECKSIG)
608 .push_opcode(opcodes::all::OP_ELSE)
609 .push_slice(&countersignatory_htlc_key.serialize()[..])
610 .push_opcode(opcodes::all::OP_SWAP)
611 .push_opcode(opcodes::all::OP_SIZE)
613 .push_opcode(opcodes::all::OP_EQUAL)
614 .push_opcode(opcodes::all::OP_NOTIF)
615 .push_opcode(opcodes::all::OP_DROP)
617 .push_opcode(opcodes::all::OP_SWAP)
618 .push_slice(&broadcaster_htlc_key.serialize()[..])
620 .push_opcode(opcodes::all::OP_CHECKMULTISIG)
621 .push_opcode(opcodes::all::OP_ELSE)
622 .push_opcode(opcodes::all::OP_HASH160)
623 .push_slice(&payment_hash160)
624 .push_opcode(opcodes::all::OP_EQUALVERIFY)
625 .push_opcode(opcodes::all::OP_CHECKSIG)
626 .push_opcode(opcodes::all::OP_ENDIF);
627 if channel_type_features.supports_anchors_zero_fee_htlc_tx() {
628 bldr = bldr.push_opcode(opcodes::all::OP_PUSHNUM_1)
629 .push_opcode(opcodes::all::OP_CSV)
630 .push_opcode(opcodes::all::OP_DROP);
632 bldr.push_opcode(opcodes::all::OP_ENDIF)
635 let mut bldr = Builder::new().push_opcode(opcodes::all::OP_DUP)
636 .push_opcode(opcodes::all::OP_HASH160)
637 .push_slice(&PubkeyHash::hash(&revocation_key.serialize())[..])
638 .push_opcode(opcodes::all::OP_EQUAL)
639 .push_opcode(opcodes::all::OP_IF)
640 .push_opcode(opcodes::all::OP_CHECKSIG)
641 .push_opcode(opcodes::all::OP_ELSE)
642 .push_slice(&countersignatory_htlc_key.serialize()[..])
643 .push_opcode(opcodes::all::OP_SWAP)
644 .push_opcode(opcodes::all::OP_SIZE)
646 .push_opcode(opcodes::all::OP_EQUAL)
647 .push_opcode(opcodes::all::OP_IF)
648 .push_opcode(opcodes::all::OP_HASH160)
649 .push_slice(&payment_hash160)
650 .push_opcode(opcodes::all::OP_EQUALVERIFY)
652 .push_opcode(opcodes::all::OP_SWAP)
653 .push_slice(&broadcaster_htlc_key.serialize()[..])
655 .push_opcode(opcodes::all::OP_CHECKMULTISIG)
656 .push_opcode(opcodes::all::OP_ELSE)
657 .push_opcode(opcodes::all::OP_DROP)
658 .push_int(htlc.cltv_expiry as i64)
659 .push_opcode(opcodes::all::OP_CLTV)
660 .push_opcode(opcodes::all::OP_DROP)
661 .push_opcode(opcodes::all::OP_CHECKSIG)
662 .push_opcode(opcodes::all::OP_ENDIF);
663 if channel_type_features.supports_anchors_zero_fee_htlc_tx() {
664 bldr = bldr.push_opcode(opcodes::all::OP_PUSHNUM_1)
665 .push_opcode(opcodes::all::OP_CSV)
666 .push_opcode(opcodes::all::OP_DROP);
668 bldr.push_opcode(opcodes::all::OP_ENDIF)
673 /// Gets the witness redeemscript for an HTLC output in a commitment transaction. Note that htlc
674 /// does not need to have its previous_output_index filled.
676 pub fn get_htlc_redeemscript(htlc: &HTLCOutputInCommitment, channel_type_features: &ChannelTypeFeatures, keys: &TxCreationKeys) -> Script {
677 get_htlc_redeemscript_with_explicit_keys(htlc, channel_type_features, &keys.broadcaster_htlc_key, &keys.countersignatory_htlc_key, &keys.revocation_key)
680 /// Gets the redeemscript for a funding output from the two funding public keys.
681 /// Note that the order of funding public keys does not matter.
682 pub fn make_funding_redeemscript(broadcaster: &PublicKey, countersignatory: &PublicKey) -> Script {
683 let broadcaster_funding_key = broadcaster.serialize();
684 let countersignatory_funding_key = countersignatory.serialize();
686 make_funding_redeemscript_from_slices(&broadcaster_funding_key, &countersignatory_funding_key)
689 pub(crate) fn make_funding_redeemscript_from_slices(broadcaster_funding_key: &[u8], countersignatory_funding_key: &[u8]) -> Script {
690 let builder = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2);
691 if broadcaster_funding_key[..] < countersignatory_funding_key[..] {
692 builder.push_slice(broadcaster_funding_key)
693 .push_slice(countersignatory_funding_key)
695 builder.push_slice(countersignatory_funding_key)
696 .push_slice(broadcaster_funding_key)
697 }.push_opcode(opcodes::all::OP_PUSHNUM_2).push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script()
700 /// Builds an unsigned HTLC-Success or HTLC-Timeout transaction from the given channel and HTLC
701 /// parameters. This is used by [`TrustedCommitmentTransaction::get_htlc_sigs`] to fetch the
702 /// transaction which needs signing, and can be used to construct an HTLC transaction which is
703 /// broadcastable given a counterparty HTLC signature.
705 /// Panics if htlc.transaction_output_index.is_none() (as such HTLCs do not appear in the
706 /// commitment transaction).
707 pub fn build_htlc_transaction(commitment_txid: &Txid, feerate_per_kw: u32, contest_delay: u16, htlc: &HTLCOutputInCommitment, channel_type_features: &ChannelTypeFeatures, broadcaster_delayed_payment_key: &PublicKey, revocation_key: &PublicKey) -> Transaction {
708 let mut txins: Vec<TxIn> = Vec::new();
709 txins.push(build_htlc_input(commitment_txid, htlc, channel_type_features));
711 let mut txouts: Vec<TxOut> = Vec::new();
712 txouts.push(build_htlc_output(
713 feerate_per_kw, contest_delay, htlc, channel_type_features,
714 broadcaster_delayed_payment_key, revocation_key
719 lock_time: PackedLockTime(if htlc.offered { htlc.cltv_expiry } else { 0 }),
725 pub(crate) fn build_htlc_input(commitment_txid: &Txid, htlc: &HTLCOutputInCommitment, channel_type_features: &ChannelTypeFeatures) -> TxIn {
727 previous_output: OutPoint {
728 txid: commitment_txid.clone(),
729 vout: htlc.transaction_output_index.expect("Can't build an HTLC transaction for a dust output"),
731 script_sig: Script::new(),
732 sequence: Sequence(if channel_type_features.supports_anchors_zero_fee_htlc_tx() { 1 } else { 0 }),
733 witness: Witness::new(),
737 pub(crate) fn build_htlc_output(
738 feerate_per_kw: u32, contest_delay: u16, htlc: &HTLCOutputInCommitment, channel_type_features: &ChannelTypeFeatures, broadcaster_delayed_payment_key: &PublicKey, revocation_key: &PublicKey
740 let weight = if htlc.offered {
741 htlc_timeout_tx_weight(channel_type_features)
743 htlc_success_tx_weight(channel_type_features)
745 let output_value = if channel_type_features.supports_anchors_zero_fee_htlc_tx() && !channel_type_features.supports_anchors_nonzero_fee_htlc_tx() {
746 htlc.amount_msat / 1000
748 let total_fee = feerate_per_kw as u64 * weight / 1000;
749 htlc.amount_msat / 1000 - total_fee
753 script_pubkey: get_revokeable_redeemscript(revocation_key, contest_delay, broadcaster_delayed_payment_key).to_v0_p2wsh(),
758 /// Returns the witness required to satisfy and spend a HTLC input.
759 pub fn build_htlc_input_witness(
760 local_sig: &Signature, remote_sig: &Signature, preimage: &Option<PaymentPreimage>,
761 redeem_script: &Script, channel_type_features: &ChannelTypeFeatures,
763 let remote_sighash_type = if channel_type_features.supports_anchors_zero_fee_htlc_tx() {
764 EcdsaSighashType::SinglePlusAnyoneCanPay
766 EcdsaSighashType::All
769 let mut witness = Witness::new();
770 // First push the multisig dummy, note that due to BIP147 (NULLDUMMY) it must be a zero-length element.
771 witness.push(vec![]);
772 witness.push_bitcoin_signature(&remote_sig.serialize_der(), remote_sighash_type);
773 witness.push_bitcoin_signature(&local_sig.serialize_der(), EcdsaSighashType::All);
774 if let Some(preimage) = preimage {
775 witness.push(preimage.0.to_vec());
777 // Due to BIP146 (MINIMALIF) this must be a zero-length element to relay.
778 witness.push(vec![]);
780 witness.push(redeem_script.to_bytes());
784 /// Pre-anchors channel type features did not use to get serialized in the following six structs:
785 /// — [`ChannelTransactionParameters`]
786 /// — [`CommitmentTransaction`]
787 /// — [`CounterpartyOfferedHTLCOutput`]
788 /// — [`CounterpartyReceivedHTLCOutput`]
789 /// — [`HolderHTLCOutput`]
790 /// — [`HolderFundingOutput`]
792 /// To ensure a forwards-compatible serialization, we use odd TLV fields. However, if new features
793 /// are used that could break security, where old signers should be prevented from handling the
794 /// serialized data, an optional even-field TLV will be used as a stand-in to break compatibility.
796 /// This method determines whether or not that option needs to be set based on the chanenl type
797 /// features, and returns it.
799 /// [`CounterpartyOfferedHTLCOutput`]: crate::chain::package::CounterpartyOfferedHTLCOutput
800 /// [`CounterpartyReceivedHTLCOutput`]: crate::chain::package::CounterpartyReceivedHTLCOutput
801 /// [`HolderHTLCOutput`]: crate::chain::package::HolderHTLCOutput
802 /// [`HolderFundingOutput`]: crate::chain::package::HolderFundingOutput
803 pub(crate) fn legacy_deserialization_prevention_marker_for_channel_type_features(features: &ChannelTypeFeatures) -> Option<()> {
804 let mut legacy_version_bit_set = ChannelTypeFeatures::only_static_remote_key();
805 legacy_version_bit_set.set_scid_privacy_required();
806 legacy_version_bit_set.set_zero_conf_required();
808 if features.is_subset(&legacy_version_bit_set) {
815 /// Gets the witnessScript for the to_remote output when anchors are enabled.
817 pub fn get_to_countersignatory_with_anchors_redeemscript(payment_point: &PublicKey) -> Script {
819 .push_slice(&payment_point.serialize()[..])
820 .push_opcode(opcodes::all::OP_CHECKSIGVERIFY)
822 .push_opcode(opcodes::all::OP_CSV)
826 /// Gets the witnessScript for an anchor output from the funding public key.
827 /// The witness in the spending input must be:
828 /// <BIP 143 funding_signature>
829 /// After 16 blocks of confirmation, an alternative satisfying witness could be:
831 /// (empty vector required to satisfy compliance with MINIMALIF-standard rule)
833 pub fn get_anchor_redeemscript(funding_pubkey: &PublicKey) -> Script {
834 Builder::new().push_slice(&funding_pubkey.serialize()[..])
835 .push_opcode(opcodes::all::OP_CHECKSIG)
836 .push_opcode(opcodes::all::OP_IFDUP)
837 .push_opcode(opcodes::all::OP_NOTIF)
839 .push_opcode(opcodes::all::OP_CSV)
840 .push_opcode(opcodes::all::OP_ENDIF)
844 /// Locates the output with an anchor script paying to `funding_pubkey` within `commitment_tx`.
845 pub(crate) fn get_anchor_output<'a>(commitment_tx: &'a Transaction, funding_pubkey: &PublicKey) -> Option<(u32, &'a TxOut)> {
846 let anchor_script = chan_utils::get_anchor_redeemscript(funding_pubkey).to_v0_p2wsh();
847 commitment_tx.output.iter().enumerate()
848 .find(|(_, txout)| txout.script_pubkey == anchor_script)
849 .map(|(idx, txout)| (idx as u32, txout))
852 /// Returns the witness required to satisfy and spend an anchor input.
853 pub fn build_anchor_input_witness(funding_key: &PublicKey, funding_sig: &Signature) -> Witness {
854 let anchor_redeem_script = chan_utils::get_anchor_redeemscript(funding_key);
855 let mut ret = Witness::new();
856 ret.push_bitcoin_signature(&funding_sig.serialize_der(), EcdsaSighashType::All);
857 ret.push(anchor_redeem_script.as_bytes());
861 /// Per-channel data used to build transactions in conjunction with the per-commitment data (CommitmentTransaction).
862 /// The fields are organized by holder/counterparty.
864 /// Normally, this is converted to the broadcaster/countersignatory-organized DirectedChannelTransactionParameters
865 /// before use, via the as_holder_broadcastable and as_counterparty_broadcastable functions.
866 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
867 pub struct ChannelTransactionParameters {
868 /// Holder public keys
869 pub holder_pubkeys: ChannelPublicKeys,
870 /// The contest delay selected by the holder, which applies to counterparty-broadcast transactions
871 pub holder_selected_contest_delay: u16,
872 /// Whether the holder is the initiator of this channel.
873 /// This is an input to the commitment number obscure factor computation.
874 pub is_outbound_from_holder: bool,
875 /// The late-bound counterparty channel transaction parameters.
876 /// These parameters are populated at the point in the protocol where the counterparty provides them.
877 pub counterparty_parameters: Option<CounterpartyChannelTransactionParameters>,
878 /// The late-bound funding outpoint
879 pub funding_outpoint: Option<chain::transaction::OutPoint>,
880 /// This channel's type, as negotiated during channel open. For old objects where this field
881 /// wasn't serialized, it will default to static_remote_key at deserialization.
882 pub channel_type_features: ChannelTypeFeatures
885 /// Late-bound per-channel counterparty data used to build transactions.
886 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
887 pub struct CounterpartyChannelTransactionParameters {
888 /// Counter-party public keys
889 pub pubkeys: ChannelPublicKeys,
890 /// The contest delay selected by the counterparty, which applies to holder-broadcast transactions
891 pub selected_contest_delay: u16,
894 impl ChannelTransactionParameters {
895 /// Whether the late bound parameters are populated.
896 pub fn is_populated(&self) -> bool {
897 self.counterparty_parameters.is_some() && self.funding_outpoint.is_some()
900 /// Convert the holder/counterparty parameters to broadcaster/countersignatory-organized parameters,
901 /// given that the holder is the broadcaster.
903 /// self.is_populated() must be true before calling this function.
904 pub fn as_holder_broadcastable(&self) -> DirectedChannelTransactionParameters {
905 assert!(self.is_populated(), "self.late_parameters must be set before using as_holder_broadcastable");
906 DirectedChannelTransactionParameters {
908 holder_is_broadcaster: true
912 /// Convert the holder/counterparty parameters to broadcaster/countersignatory-organized parameters,
913 /// given that the counterparty is the broadcaster.
915 /// self.is_populated() must be true before calling this function.
916 pub fn as_counterparty_broadcastable(&self) -> DirectedChannelTransactionParameters {
917 assert!(self.is_populated(), "self.late_parameters must be set before using as_counterparty_broadcastable");
918 DirectedChannelTransactionParameters {
920 holder_is_broadcaster: false
925 impl_writeable_tlv_based!(CounterpartyChannelTransactionParameters, {
926 (0, pubkeys, required),
927 (2, selected_contest_delay, required),
930 impl Writeable for ChannelTransactionParameters {
931 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
932 let legacy_deserialization_prevention_marker = legacy_deserialization_prevention_marker_for_channel_type_features(&self.channel_type_features);
933 write_tlv_fields!(writer, {
934 (0, self.holder_pubkeys, required),
935 (2, self.holder_selected_contest_delay, required),
936 (4, self.is_outbound_from_holder, required),
937 (6, self.counterparty_parameters, option),
938 (8, self.funding_outpoint, option),
939 (10, legacy_deserialization_prevention_marker, option),
940 (11, self.channel_type_features, required),
946 impl Readable for ChannelTransactionParameters {
947 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
948 let mut holder_pubkeys = RequiredWrapper(None);
949 let mut holder_selected_contest_delay = RequiredWrapper(None);
950 let mut is_outbound_from_holder = RequiredWrapper(None);
951 let mut counterparty_parameters = None;
952 let mut funding_outpoint = None;
953 let mut _legacy_deserialization_prevention_marker: Option<()> = None;
954 let mut channel_type_features = None;
956 read_tlv_fields!(reader, {
957 (0, holder_pubkeys, required),
958 (2, holder_selected_contest_delay, required),
959 (4, is_outbound_from_holder, required),
960 (6, counterparty_parameters, option),
961 (8, funding_outpoint, option),
962 (10, _legacy_deserialization_prevention_marker, option),
963 (11, channel_type_features, option),
966 let mut additional_features = ChannelTypeFeatures::empty();
967 additional_features.set_anchors_nonzero_fee_htlc_tx_required();
968 chain::package::verify_channel_type_features(&channel_type_features, Some(&additional_features))?;
971 holder_pubkeys: holder_pubkeys.0.unwrap(),
972 holder_selected_contest_delay: holder_selected_contest_delay.0.unwrap(),
973 is_outbound_from_holder: is_outbound_from_holder.0.unwrap(),
974 counterparty_parameters,
976 channel_type_features: channel_type_features.unwrap_or(ChannelTypeFeatures::only_static_remote_key())
981 /// Static channel fields used to build transactions given per-commitment fields, organized by
982 /// broadcaster/countersignatory.
984 /// This is derived from the holder/counterparty-organized ChannelTransactionParameters via the
985 /// as_holder_broadcastable and as_counterparty_broadcastable functions.
986 pub struct DirectedChannelTransactionParameters<'a> {
987 /// The holder's channel static parameters
988 inner: &'a ChannelTransactionParameters,
989 /// Whether the holder is the broadcaster
990 holder_is_broadcaster: bool,
993 impl<'a> DirectedChannelTransactionParameters<'a> {
994 /// Get the channel pubkeys for the broadcaster
995 pub fn broadcaster_pubkeys(&self) -> &'a ChannelPublicKeys {
996 if self.holder_is_broadcaster {
997 &self.inner.holder_pubkeys
999 &self.inner.counterparty_parameters.as_ref().unwrap().pubkeys
1003 /// Get the channel pubkeys for the countersignatory
1004 pub fn countersignatory_pubkeys(&self) -> &'a ChannelPublicKeys {
1005 if self.holder_is_broadcaster {
1006 &self.inner.counterparty_parameters.as_ref().unwrap().pubkeys
1008 &self.inner.holder_pubkeys
1012 /// Get the contest delay applicable to the transactions.
1013 /// Note that the contest delay was selected by the countersignatory.
1014 pub fn contest_delay(&self) -> u16 {
1015 let counterparty_parameters = self.inner.counterparty_parameters.as_ref().unwrap();
1016 if self.holder_is_broadcaster { counterparty_parameters.selected_contest_delay } else { self.inner.holder_selected_contest_delay }
1019 /// Whether the channel is outbound from the broadcaster.
1021 /// The boolean representing the side that initiated the channel is
1022 /// an input to the commitment number obscure factor computation.
1023 pub fn is_outbound(&self) -> bool {
1024 if self.holder_is_broadcaster { self.inner.is_outbound_from_holder } else { !self.inner.is_outbound_from_holder }
1027 /// The funding outpoint
1028 pub fn funding_outpoint(&self) -> OutPoint {
1029 self.inner.funding_outpoint.unwrap().into_bitcoin_outpoint()
1032 /// Whether to use anchors for this channel
1033 pub fn channel_type_features(&self) -> &'a ChannelTypeFeatures {
1034 &self.inner.channel_type_features
1038 /// Information needed to build and sign a holder's commitment transaction.
1040 /// The transaction is only signed once we are ready to broadcast.
1041 #[derive(Clone, Debug)]
1042 pub struct HolderCommitmentTransaction {
1043 inner: CommitmentTransaction,
1044 /// Our counterparty's signature for the transaction
1045 pub counterparty_sig: Signature,
1046 /// All non-dust counterparty HTLC signatures, in the order they appear in the transaction
1047 pub counterparty_htlc_sigs: Vec<Signature>,
1048 // Which order the signatures should go in when constructing the final commitment tx witness.
1049 // The user should be able to reconstruct this themselves, so we don't bother to expose it.
1050 holder_sig_first: bool,
1053 impl Deref for HolderCommitmentTransaction {
1054 type Target = CommitmentTransaction;
1056 fn deref(&self) -> &Self::Target { &self.inner }
1059 impl Eq for HolderCommitmentTransaction {}
1060 impl PartialEq for HolderCommitmentTransaction {
1061 // We dont care whether we are signed in equality comparison
1062 fn eq(&self, o: &Self) -> bool {
1063 self.inner == o.inner
1067 impl_writeable_tlv_based!(HolderCommitmentTransaction, {
1068 (0, inner, required),
1069 (2, counterparty_sig, required),
1070 (4, holder_sig_first, required),
1071 (6, counterparty_htlc_sigs, required_vec),
1074 impl HolderCommitmentTransaction {
1076 pub fn dummy(htlcs: &mut Vec<(HTLCOutputInCommitment, ())>) -> Self {
1077 let secp_ctx = Secp256k1::new();
1078 let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
1079 let dummy_sig = sign(&secp_ctx, &secp256k1::Message::from_slice(&[42; 32]).unwrap(), &SecretKey::from_slice(&[42; 32]).unwrap());
1081 let keys = TxCreationKeys {
1082 per_commitment_point: dummy_key.clone(),
1083 revocation_key: dummy_key.clone(),
1084 broadcaster_htlc_key: dummy_key.clone(),
1085 countersignatory_htlc_key: dummy_key.clone(),
1086 broadcaster_delayed_payment_key: dummy_key.clone(),
1088 let channel_pubkeys = ChannelPublicKeys {
1089 funding_pubkey: dummy_key.clone(),
1090 revocation_basepoint: dummy_key.clone(),
1091 payment_point: dummy_key.clone(),
1092 delayed_payment_basepoint: dummy_key.clone(),
1093 htlc_basepoint: dummy_key.clone()
1095 let channel_parameters = ChannelTransactionParameters {
1096 holder_pubkeys: channel_pubkeys.clone(),
1097 holder_selected_contest_delay: 0,
1098 is_outbound_from_holder: false,
1099 counterparty_parameters: Some(CounterpartyChannelTransactionParameters { pubkeys: channel_pubkeys.clone(), selected_contest_delay: 0 }),
1100 funding_outpoint: Some(chain::transaction::OutPoint { txid: Txid::all_zeros(), index: 0 }),
1101 channel_type_features: ChannelTypeFeatures::only_static_remote_key(),
1103 let mut counterparty_htlc_sigs = Vec::new();
1104 for _ in 0..htlcs.len() {
1105 counterparty_htlc_sigs.push(dummy_sig);
1107 let inner = CommitmentTransaction::new_with_auxiliary_htlc_data(0, 0, 0, dummy_key.clone(), dummy_key.clone(), keys, 0, htlcs, &channel_parameters.as_counterparty_broadcastable());
1108 htlcs.sort_by_key(|htlc| htlc.0.transaction_output_index);
1109 HolderCommitmentTransaction {
1111 counterparty_sig: dummy_sig,
1112 counterparty_htlc_sigs,
1113 holder_sig_first: false
1117 /// Create a new holder transaction with the given counterparty signatures.
1118 /// The funding keys are used to figure out which signature should go first when building the transaction for broadcast.
1119 pub fn new(commitment_tx: CommitmentTransaction, counterparty_sig: Signature, counterparty_htlc_sigs: Vec<Signature>, holder_funding_key: &PublicKey, counterparty_funding_key: &PublicKey) -> Self {
1121 inner: commitment_tx,
1123 counterparty_htlc_sigs,
1124 holder_sig_first: holder_funding_key.serialize()[..] < counterparty_funding_key.serialize()[..],
1128 pub(crate) fn add_holder_sig(&self, funding_redeemscript: &Script, holder_sig: Signature) -> Transaction {
1129 // First push the multisig dummy, note that due to BIP147 (NULLDUMMY) it must be a zero-length element.
1130 let mut tx = self.inner.built.transaction.clone();
1131 tx.input[0].witness.push(Vec::new());
1133 if self.holder_sig_first {
1134 tx.input[0].witness.push_bitcoin_signature(&holder_sig.serialize_der(), EcdsaSighashType::All);
1135 tx.input[0].witness.push_bitcoin_signature(&self.counterparty_sig.serialize_der(), EcdsaSighashType::All);
1137 tx.input[0].witness.push_bitcoin_signature(&self.counterparty_sig.serialize_der(), EcdsaSighashType::All);
1138 tx.input[0].witness.push_bitcoin_signature(&holder_sig.serialize_der(), EcdsaSighashType::All);
1141 tx.input[0].witness.push(funding_redeemscript.as_bytes().to_vec());
1146 /// A pre-built Bitcoin commitment transaction and its txid.
1147 #[derive(Clone, Debug)]
1148 pub struct BuiltCommitmentTransaction {
1149 /// The commitment transaction
1150 pub transaction: Transaction,
1151 /// The txid for the commitment transaction.
1153 /// This is provided as a performance optimization, instead of calling transaction.txid()
1158 impl_writeable_tlv_based!(BuiltCommitmentTransaction, {
1159 (0, transaction, required),
1160 (2, txid, required),
1163 impl BuiltCommitmentTransaction {
1164 /// Get the SIGHASH_ALL sighash value of the transaction.
1166 /// This can be used to verify a signature.
1167 pub fn get_sighash_all(&self, funding_redeemscript: &Script, channel_value_satoshis: u64) -> Message {
1168 let sighash = &sighash::SighashCache::new(&self.transaction).segwit_signature_hash(0, funding_redeemscript, channel_value_satoshis, EcdsaSighashType::All).unwrap()[..];
1169 hash_to_message!(sighash)
1172 /// Signs the counterparty's commitment transaction.
1173 pub fn sign_counterparty_commitment<T: secp256k1::Signing>(&self, funding_key: &SecretKey, funding_redeemscript: &Script, channel_value_satoshis: u64, secp_ctx: &Secp256k1<T>) -> Signature {
1174 let sighash = self.get_sighash_all(funding_redeemscript, channel_value_satoshis);
1175 sign(secp_ctx, &sighash, funding_key)
1178 /// Signs the holder commitment transaction because we are about to broadcast it.
1179 pub fn sign_holder_commitment<T: secp256k1::Signing, ES: Deref>(
1180 &self, funding_key: &SecretKey, funding_redeemscript: &Script, channel_value_satoshis: u64,
1181 entropy_source: &ES, secp_ctx: &Secp256k1<T>
1182 ) -> Signature where ES::Target: EntropySource {
1183 let sighash = self.get_sighash_all(funding_redeemscript, channel_value_satoshis);
1184 sign_with_aux_rand(secp_ctx, &sighash, funding_key, entropy_source)
1188 /// This class tracks the per-transaction information needed to build a closing transaction and will
1189 /// actually build it and sign.
1191 /// This class can be used inside a signer implementation to generate a signature given the relevant
1193 #[derive(Clone, Hash, PartialEq, Eq)]
1194 pub struct ClosingTransaction {
1195 to_holder_value_sat: u64,
1196 to_counterparty_value_sat: u64,
1197 to_holder_script: Script,
1198 to_counterparty_script: Script,
1202 impl ClosingTransaction {
1203 /// Construct an object of the class
1205 to_holder_value_sat: u64,
1206 to_counterparty_value_sat: u64,
1207 to_holder_script: Script,
1208 to_counterparty_script: Script,
1209 funding_outpoint: OutPoint,
1211 let built = build_closing_transaction(
1212 to_holder_value_sat, to_counterparty_value_sat,
1213 to_holder_script.clone(), to_counterparty_script.clone(),
1216 ClosingTransaction {
1217 to_holder_value_sat,
1218 to_counterparty_value_sat,
1220 to_counterparty_script,
1225 /// Trust our pre-built transaction.
1227 /// Applies a wrapper which allows access to the transaction.
1229 /// This should only be used if you fully trust the builder of this object. It should not
1230 /// be used by an external signer - instead use the verify function.
1231 pub fn trust(&self) -> TrustedClosingTransaction {
1232 TrustedClosingTransaction { inner: self }
1235 /// Verify our pre-built transaction.
1237 /// Applies a wrapper which allows access to the transaction.
1239 /// An external validating signer must call this method before signing
1240 /// or using the built transaction.
1241 pub fn verify(&self, funding_outpoint: OutPoint) -> Result<TrustedClosingTransaction, ()> {
1242 let built = build_closing_transaction(
1243 self.to_holder_value_sat, self.to_counterparty_value_sat,
1244 self.to_holder_script.clone(), self.to_counterparty_script.clone(),
1247 if self.built != built {
1250 Ok(TrustedClosingTransaction { inner: self })
1253 /// The value to be sent to the holder, or zero if the output will be omitted
1254 pub fn to_holder_value_sat(&self) -> u64 {
1255 self.to_holder_value_sat
1258 /// The value to be sent to the counterparty, or zero if the output will be omitted
1259 pub fn to_counterparty_value_sat(&self) -> u64 {
1260 self.to_counterparty_value_sat
1263 /// The destination of the holder's output
1264 pub fn to_holder_script(&self) -> &Script {
1265 &self.to_holder_script
1268 /// The destination of the counterparty's output
1269 pub fn to_counterparty_script(&self) -> &Script {
1270 &self.to_counterparty_script
1274 /// A wrapper on ClosingTransaction indicating that the built bitcoin
1275 /// transaction is trusted.
1277 /// See trust() and verify() functions on CommitmentTransaction.
1279 /// This structure implements Deref.
1280 pub struct TrustedClosingTransaction<'a> {
1281 inner: &'a ClosingTransaction,
1284 impl<'a> Deref for TrustedClosingTransaction<'a> {
1285 type Target = ClosingTransaction;
1287 fn deref(&self) -> &Self::Target { self.inner }
1290 impl<'a> TrustedClosingTransaction<'a> {
1291 /// The pre-built Bitcoin commitment transaction
1292 pub fn built_transaction(&self) -> &'a Transaction {
1296 /// Get the SIGHASH_ALL sighash value of the transaction.
1298 /// This can be used to verify a signature.
1299 pub fn get_sighash_all(&self, funding_redeemscript: &Script, channel_value_satoshis: u64) -> Message {
1300 let sighash = &sighash::SighashCache::new(&self.inner.built).segwit_signature_hash(0, funding_redeemscript, channel_value_satoshis, EcdsaSighashType::All).unwrap()[..];
1301 hash_to_message!(sighash)
1304 /// Sign a transaction, either because we are counter-signing the counterparty's transaction or
1305 /// because we are about to broadcast a holder transaction.
1306 pub fn sign<T: secp256k1::Signing>(&self, funding_key: &SecretKey, funding_redeemscript: &Script, channel_value_satoshis: u64, secp_ctx: &Secp256k1<T>) -> Signature {
1307 let sighash = self.get_sighash_all(funding_redeemscript, channel_value_satoshis);
1308 sign(secp_ctx, &sighash, funding_key)
1312 /// This class tracks the per-transaction information needed to build a commitment transaction and will
1313 /// actually build it and sign. It is used for holder transactions that we sign only when needed
1314 /// and for transactions we sign for the counterparty.
1316 /// This class can be used inside a signer implementation to generate a signature given the relevant
1318 #[derive(Clone, Debug)]
1319 pub struct CommitmentTransaction {
1320 commitment_number: u64,
1321 to_broadcaster_value_sat: u64,
1322 to_countersignatory_value_sat: u64,
1323 to_broadcaster_delay: Option<u16>, // Added in 0.0.117
1324 feerate_per_kw: u32,
1325 htlcs: Vec<HTLCOutputInCommitment>,
1326 // Note that on upgrades, some features of existing outputs may be missed.
1327 channel_type_features: ChannelTypeFeatures,
1328 // A cache of the parties' pubkeys required to construct the transaction, see doc for trust()
1329 keys: TxCreationKeys,
1330 // For access to the pre-built transaction, see doc for trust()
1331 built: BuiltCommitmentTransaction,
1334 impl Eq for CommitmentTransaction {}
1335 impl PartialEq for CommitmentTransaction {
1336 fn eq(&self, o: &Self) -> bool {
1337 let eq = self.commitment_number == o.commitment_number &&
1338 self.to_broadcaster_value_sat == o.to_broadcaster_value_sat &&
1339 self.to_countersignatory_value_sat == o.to_countersignatory_value_sat &&
1340 self.feerate_per_kw == o.feerate_per_kw &&
1341 self.htlcs == o.htlcs &&
1342 self.channel_type_features == o.channel_type_features &&
1343 self.keys == o.keys;
1345 debug_assert_eq!(self.built.transaction, o.built.transaction);
1346 debug_assert_eq!(self.built.txid, o.built.txid);
1352 impl Writeable for CommitmentTransaction {
1353 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
1354 let legacy_deserialization_prevention_marker = legacy_deserialization_prevention_marker_for_channel_type_features(&self.channel_type_features);
1355 write_tlv_fields!(writer, {
1356 (0, self.commitment_number, required),
1357 (1, self.to_broadcaster_delay, option),
1358 (2, self.to_broadcaster_value_sat, required),
1359 (4, self.to_countersignatory_value_sat, required),
1360 (6, self.feerate_per_kw, required),
1361 (8, self.keys, required),
1362 (10, self.built, required),
1363 (12, self.htlcs, required_vec),
1364 (14, legacy_deserialization_prevention_marker, option),
1365 (15, self.channel_type_features, required),
1371 impl Readable for CommitmentTransaction {
1372 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
1373 _init_and_read_len_prefixed_tlv_fields!(reader, {
1374 (0, commitment_number, required),
1375 (1, to_broadcaster_delay, option),
1376 (2, to_broadcaster_value_sat, required),
1377 (4, to_countersignatory_value_sat, required),
1378 (6, feerate_per_kw, required),
1379 (8, keys, required),
1380 (10, built, required),
1381 (12, htlcs, required_vec),
1382 (14, _legacy_deserialization_prevention_marker, option),
1383 (15, channel_type_features, option),
1386 let mut additional_features = ChannelTypeFeatures::empty();
1387 additional_features.set_anchors_nonzero_fee_htlc_tx_required();
1388 chain::package::verify_channel_type_features(&channel_type_features, Some(&additional_features))?;
1391 commitment_number: commitment_number.0.unwrap(),
1392 to_broadcaster_value_sat: to_broadcaster_value_sat.0.unwrap(),
1393 to_countersignatory_value_sat: to_countersignatory_value_sat.0.unwrap(),
1394 to_broadcaster_delay,
1395 feerate_per_kw: feerate_per_kw.0.unwrap(),
1396 keys: keys.0.unwrap(),
1397 built: built.0.unwrap(),
1399 channel_type_features: channel_type_features.unwrap_or(ChannelTypeFeatures::only_static_remote_key())
1404 impl CommitmentTransaction {
1405 /// Construct an object of the class while assigning transaction output indices to HTLCs.
1407 /// Populates HTLCOutputInCommitment.transaction_output_index in htlcs_with_aux.
1409 /// The generic T allows the caller to match the HTLC output index with auxiliary data.
1410 /// This auxiliary data is not stored in this object.
1412 /// Only include HTLCs that are above the dust limit for the channel.
1414 /// This is not exported to bindings users due to the generic though we likely should expose a version without
1415 pub fn new_with_auxiliary_htlc_data<T>(commitment_number: u64, to_broadcaster_value_sat: u64, to_countersignatory_value_sat: u64, broadcaster_funding_key: PublicKey, countersignatory_funding_key: PublicKey, keys: TxCreationKeys, feerate_per_kw: u32, htlcs_with_aux: &mut Vec<(HTLCOutputInCommitment, T)>, channel_parameters: &DirectedChannelTransactionParameters) -> CommitmentTransaction {
1416 // Sort outputs and populate output indices while keeping track of the auxiliary data
1417 let (outputs, htlcs) = Self::internal_build_outputs(&keys, to_broadcaster_value_sat, to_countersignatory_value_sat, htlcs_with_aux, channel_parameters, &broadcaster_funding_key, &countersignatory_funding_key).unwrap();
1419 let (obscured_commitment_transaction_number, txins) = Self::internal_build_inputs(commitment_number, channel_parameters);
1420 let transaction = Self::make_transaction(obscured_commitment_transaction_number, txins, outputs);
1421 let txid = transaction.txid();
1422 CommitmentTransaction {
1424 to_broadcaster_value_sat,
1425 to_countersignatory_value_sat,
1426 to_broadcaster_delay: Some(channel_parameters.contest_delay()),
1429 channel_type_features: channel_parameters.channel_type_features().clone(),
1431 built: BuiltCommitmentTransaction {
1438 /// Use non-zero fee anchors
1440 /// This is not exported to bindings users due to move, and also not likely to be useful for binding users
1441 pub fn with_non_zero_fee_anchors(mut self) -> Self {
1442 self.channel_type_features.set_anchors_nonzero_fee_htlc_tx_required();
1446 fn internal_rebuild_transaction(&self, keys: &TxCreationKeys, channel_parameters: &DirectedChannelTransactionParameters, broadcaster_funding_key: &PublicKey, countersignatory_funding_key: &PublicKey) -> Result<BuiltCommitmentTransaction, ()> {
1447 let (obscured_commitment_transaction_number, txins) = Self::internal_build_inputs(self.commitment_number, channel_parameters);
1449 let mut htlcs_with_aux = self.htlcs.iter().map(|h| (h.clone(), ())).collect();
1450 let (outputs, _) = Self::internal_build_outputs(keys, self.to_broadcaster_value_sat, self.to_countersignatory_value_sat, &mut htlcs_with_aux, channel_parameters, broadcaster_funding_key, countersignatory_funding_key)?;
1452 let transaction = Self::make_transaction(obscured_commitment_transaction_number, txins, outputs);
1453 let txid = transaction.txid();
1454 let built_transaction = BuiltCommitmentTransaction {
1458 Ok(built_transaction)
1461 fn make_transaction(obscured_commitment_transaction_number: u64, txins: Vec<TxIn>, outputs: Vec<TxOut>) -> Transaction {
1464 lock_time: PackedLockTime(((0x20 as u32) << 8 * 3) | ((obscured_commitment_transaction_number & 0xffffffu64) as u32)),
1470 // This is used in two cases:
1471 // - initial sorting of outputs / HTLCs in the constructor, in which case T is auxiliary data the
1472 // caller needs to have sorted together with the HTLCs so it can keep track of the output index
1473 // - building of a bitcoin transaction during a verify() call, in which case T is just ()
1474 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, broadcaster_funding_key: &PublicKey, countersignatory_funding_key: &PublicKey) -> Result<(Vec<TxOut>, Vec<HTLCOutputInCommitment>), ()> {
1475 let countersignatory_pubkeys = channel_parameters.countersignatory_pubkeys();
1476 let contest_delay = channel_parameters.contest_delay();
1478 let mut txouts: Vec<(TxOut, Option<&mut HTLCOutputInCommitment>)> = Vec::new();
1480 if to_countersignatory_value_sat > 0 {
1481 let script = if channel_parameters.channel_type_features().supports_anchors_zero_fee_htlc_tx() {
1482 get_to_countersignatory_with_anchors_redeemscript(&countersignatory_pubkeys.payment_point).to_v0_p2wsh()
1484 Payload::p2wpkh(&BitcoinPublicKey::new(countersignatory_pubkeys.payment_point)).unwrap().script_pubkey()
1488 script_pubkey: script.clone(),
1489 value: to_countersignatory_value_sat,
1495 if to_broadcaster_value_sat > 0 {
1496 let redeem_script = get_revokeable_redeemscript(
1497 &keys.revocation_key,
1499 &keys.broadcaster_delayed_payment_key,
1503 script_pubkey: redeem_script.to_v0_p2wsh(),
1504 value: to_broadcaster_value_sat,
1510 if channel_parameters.channel_type_features().supports_anchors_zero_fee_htlc_tx() {
1511 if to_broadcaster_value_sat > 0 || !htlcs_with_aux.is_empty() {
1512 let anchor_script = get_anchor_redeemscript(broadcaster_funding_key);
1515 script_pubkey: anchor_script.to_v0_p2wsh(),
1516 value: ANCHOR_OUTPUT_VALUE_SATOSHI,
1522 if to_countersignatory_value_sat > 0 || !htlcs_with_aux.is_empty() {
1523 let anchor_script = get_anchor_redeemscript(countersignatory_funding_key);
1526 script_pubkey: anchor_script.to_v0_p2wsh(),
1527 value: ANCHOR_OUTPUT_VALUE_SATOSHI,
1534 let mut htlcs = Vec::with_capacity(htlcs_with_aux.len());
1535 for (htlc, _) in htlcs_with_aux {
1536 let script = chan_utils::get_htlc_redeemscript(&htlc, &channel_parameters.channel_type_features(), &keys);
1538 script_pubkey: script.to_v0_p2wsh(),
1539 value: htlc.amount_msat / 1000,
1541 txouts.push((txout, Some(htlc)));
1544 // Sort output in BIP-69 order (amount, scriptPubkey). Tie-breaks based on HTLC
1545 // CLTV expiration height.
1546 sort_outputs(&mut txouts, |a, b| {
1547 if let &Some(ref a_htlcout) = a {
1548 if let &Some(ref b_htlcout) = b {
1549 a_htlcout.cltv_expiry.cmp(&b_htlcout.cltv_expiry)
1550 // Note that due to hash collisions, we have to have a fallback comparison
1551 // here for fuzzing mode (otherwise at least chanmon_fail_consistency
1553 .then(a_htlcout.payment_hash.0.cmp(&b_htlcout.payment_hash.0))
1554 // For non-HTLC outputs, if they're copying our SPK we don't really care if we
1555 // close the channel due to mismatches - they're doing something dumb:
1556 } else { cmp::Ordering::Equal }
1557 } else { cmp::Ordering::Equal }
1560 let mut outputs = Vec::with_capacity(txouts.len());
1561 for (idx, out) in txouts.drain(..).enumerate() {
1562 if let Some(htlc) = out.1 {
1563 htlc.transaction_output_index = Some(idx as u32);
1564 htlcs.push(htlc.clone());
1566 outputs.push(out.0);
1568 Ok((outputs, htlcs))
1571 fn internal_build_inputs(commitment_number: u64, channel_parameters: &DirectedChannelTransactionParameters) -> (u64, Vec<TxIn>) {
1572 let broadcaster_pubkeys = channel_parameters.broadcaster_pubkeys();
1573 let countersignatory_pubkeys = channel_parameters.countersignatory_pubkeys();
1574 let commitment_transaction_number_obscure_factor = get_commitment_transaction_number_obscure_factor(
1575 &broadcaster_pubkeys.payment_point,
1576 &countersignatory_pubkeys.payment_point,
1577 channel_parameters.is_outbound(),
1580 let obscured_commitment_transaction_number =
1581 commitment_transaction_number_obscure_factor ^ (INITIAL_COMMITMENT_NUMBER - commitment_number);
1584 let mut ins: Vec<TxIn> = Vec::new();
1586 previous_output: channel_parameters.funding_outpoint(),
1587 script_sig: Script::new(),
1588 sequence: Sequence(((0x80 as u32) << 8 * 3)
1589 | ((obscured_commitment_transaction_number >> 3 * 8) as u32)),
1590 witness: Witness::new(),
1594 (obscured_commitment_transaction_number, txins)
1597 /// The backwards-counting commitment number
1598 pub fn commitment_number(&self) -> u64 {
1599 self.commitment_number
1602 /// The per commitment point used by the broadcaster.
1603 pub fn per_commitment_point(&self) -> PublicKey {
1604 self.keys.per_commitment_point
1607 /// The value to be sent to the broadcaster
1608 pub fn to_broadcaster_value_sat(&self) -> u64 {
1609 self.to_broadcaster_value_sat
1612 /// The value to be sent to the counterparty
1613 pub fn to_countersignatory_value_sat(&self) -> u64 {
1614 self.to_countersignatory_value_sat
1617 /// The feerate paid per 1000-weight-unit in this commitment transaction.
1618 pub fn feerate_per_kw(&self) -> u32 {
1622 /// The non-dust HTLCs (direction, amt, height expiration, hash, transaction output index)
1623 /// which were included in this commitment transaction in output order.
1624 /// The transaction index is always populated.
1626 /// This is not exported to bindings users as we cannot currently convert Vec references to/from C, though we should
1627 /// expose a less effecient version which creates a Vec of references in the future.
1628 pub fn htlcs(&self) -> &Vec<HTLCOutputInCommitment> {
1632 /// Trust our pre-built transaction and derived transaction creation public keys.
1634 /// Applies a wrapper which allows access to these fields.
1636 /// This should only be used if you fully trust the builder of this object. It should not
1637 /// be used by an external signer - instead use the verify function.
1638 pub fn trust(&self) -> TrustedCommitmentTransaction {
1639 TrustedCommitmentTransaction { inner: self }
1642 /// Verify our pre-built transaction and derived transaction creation public keys.
1644 /// Applies a wrapper which allows access to these fields.
1646 /// An external validating signer must call this method before signing
1647 /// or using the built transaction.
1648 pub fn verify<T: secp256k1::Signing + secp256k1::Verification>(&self, channel_parameters: &DirectedChannelTransactionParameters, broadcaster_keys: &ChannelPublicKeys, countersignatory_keys: &ChannelPublicKeys, secp_ctx: &Secp256k1<T>) -> Result<TrustedCommitmentTransaction, ()> {
1649 // This is the only field of the key cache that we trust
1650 let per_commitment_point = self.keys.per_commitment_point;
1651 let keys = TxCreationKeys::from_channel_static_keys(&per_commitment_point, broadcaster_keys, countersignatory_keys, secp_ctx);
1652 if keys != self.keys {
1655 let tx = self.internal_rebuild_transaction(&keys, channel_parameters, &broadcaster_keys.funding_pubkey, &countersignatory_keys.funding_pubkey)?;
1656 if self.built.transaction != tx.transaction || self.built.txid != tx.txid {
1659 Ok(TrustedCommitmentTransaction { inner: self })
1663 /// A wrapper on CommitmentTransaction indicating that the derived fields (the built bitcoin
1664 /// transaction and the transaction creation keys) are trusted.
1666 /// See trust() and verify() functions on CommitmentTransaction.
1668 /// This structure implements Deref.
1669 pub struct TrustedCommitmentTransaction<'a> {
1670 inner: &'a CommitmentTransaction,
1673 impl<'a> Deref for TrustedCommitmentTransaction<'a> {
1674 type Target = CommitmentTransaction;
1676 fn deref(&self) -> &Self::Target { self.inner }
1679 impl<'a> TrustedCommitmentTransaction<'a> {
1680 /// The transaction ID of the built Bitcoin transaction
1681 pub fn txid(&self) -> Txid {
1682 self.inner.built.txid
1685 /// The pre-built Bitcoin commitment transaction
1686 pub fn built_transaction(&self) -> &'a BuiltCommitmentTransaction {
1690 /// The pre-calculated transaction creation public keys.
1691 pub fn keys(&self) -> &'a TxCreationKeys {
1695 /// Should anchors be used.
1696 pub fn channel_type_features(&self) -> &'a ChannelTypeFeatures {
1697 &self.inner.channel_type_features
1700 /// Get a signature for each HTLC which was included in the commitment transaction (ie for
1701 /// which HTLCOutputInCommitment::transaction_output_index.is_some()).
1703 /// The returned Vec has one entry for each HTLC, and in the same order.
1705 /// This function is only valid in the holder commitment context, it always uses EcdsaSighashType::All.
1706 pub fn get_htlc_sigs<T: secp256k1::Signing, ES: Deref>(
1707 &self, htlc_base_key: &SecretKey, channel_parameters: &DirectedChannelTransactionParameters,
1708 entropy_source: &ES, secp_ctx: &Secp256k1<T>,
1709 ) -> Result<Vec<Signature>, ()> where ES::Target: EntropySource {
1710 let inner = self.inner;
1711 let keys = &inner.keys;
1712 let txid = inner.built.txid;
1713 let mut ret = Vec::with_capacity(inner.htlcs.len());
1714 let holder_htlc_key = derive_private_key(secp_ctx, &inner.keys.per_commitment_point, htlc_base_key);
1716 for this_htlc in inner.htlcs.iter() {
1717 assert!(this_htlc.transaction_output_index.is_some());
1718 let htlc_tx = build_htlc_transaction(&txid, inner.feerate_per_kw, channel_parameters.contest_delay(), &this_htlc, &self.channel_type_features, &keys.broadcaster_delayed_payment_key, &keys.revocation_key);
1720 let htlc_redeemscript = get_htlc_redeemscript_with_explicit_keys(&this_htlc, &self.channel_type_features, &keys.broadcaster_htlc_key, &keys.countersignatory_htlc_key, &keys.revocation_key);
1722 let sighash = hash_to_message!(&sighash::SighashCache::new(&htlc_tx).segwit_signature_hash(0, &htlc_redeemscript, this_htlc.amount_msat / 1000, EcdsaSighashType::All).unwrap()[..]);
1723 ret.push(sign_with_aux_rand(secp_ctx, &sighash, &holder_htlc_key, entropy_source));
1728 /// Builds the second-level holder HTLC transaction for the HTLC with index `htlc_index`.
1729 pub(crate) fn build_unsigned_htlc_tx(
1730 &self, channel_parameters: &DirectedChannelTransactionParameters, htlc_index: usize,
1731 preimage: &Option<PaymentPreimage>,
1733 let keys = &self.inner.keys;
1734 let this_htlc = &self.inner.htlcs[htlc_index];
1735 assert!(this_htlc.transaction_output_index.is_some());
1736 // if we don't have preimage for an HTLC-Success, we can't generate an HTLC transaction.
1737 if !this_htlc.offered && preimage.is_none() { unreachable!(); }
1738 // Further, we should never be provided the preimage for an HTLC-Timeout transaction.
1739 if this_htlc.offered && preimage.is_some() { unreachable!(); }
1741 build_htlc_transaction(
1742 &self.inner.built.txid, self.inner.feerate_per_kw, channel_parameters.contest_delay(), &this_htlc,
1743 &self.channel_type_features, &keys.broadcaster_delayed_payment_key, &keys.revocation_key
1748 /// Builds the witness required to spend the input for the HTLC with index `htlc_index` in a
1749 /// second-level holder HTLC transaction.
1750 pub(crate) fn build_htlc_input_witness(
1751 &self, htlc_index: usize, counterparty_signature: &Signature, signature: &Signature,
1752 preimage: &Option<PaymentPreimage>
1754 let keys = &self.inner.keys;
1755 let htlc_redeemscript = get_htlc_redeemscript_with_explicit_keys(
1756 &self.inner.htlcs[htlc_index], &self.channel_type_features, &keys.broadcaster_htlc_key,
1757 &keys.countersignatory_htlc_key, &keys.revocation_key
1759 chan_utils::build_htlc_input_witness(
1760 signature, counterparty_signature, preimage, &htlc_redeemscript, &self.channel_type_features,
1764 /// Returns the index of the revokeable output, i.e. the `to_local` output sending funds to
1765 /// the broadcaster, in the built transaction, if any exists.
1767 /// There are two cases where this may return `None`:
1768 /// - The balance of the revokeable output is below the dust limit (only found on commitments
1769 /// early in the channel's lifetime, i.e. before the channel reserve is met).
1770 /// - This commitment was created before LDK 0.0.117. In this case, the
1771 /// commitment transaction previously didn't contain enough information to locate the
1772 /// revokeable output.
1773 pub fn revokeable_output_index(&self) -> Option<usize> {
1774 let revokeable_redeemscript = get_revokeable_redeemscript(
1775 &self.keys.revocation_key,
1776 self.to_broadcaster_delay?,
1777 &self.keys.broadcaster_delayed_payment_key,
1779 let revokeable_p2wsh = revokeable_redeemscript.to_v0_p2wsh();
1780 let outputs = &self.inner.built.transaction.output;
1781 outputs.iter().enumerate()
1782 .find(|(_, out)| out.script_pubkey == revokeable_p2wsh)
1783 .map(|(idx, _)| idx)
1786 /// Helper method to build an unsigned justice transaction spending the revokeable
1787 /// `to_local` output to a destination script. Fee estimation accounts for the expected
1788 /// revocation witness data that will be added when signed.
1790 /// This method will error if the given fee rate results in a fee greater than the value
1791 /// of the output being spent, or if there exists no revokeable `to_local` output on this
1792 /// commitment transaction. See [`Self::revokeable_output_index`] for more details.
1794 /// The built transaction will allow fee bumping with RBF, and this method takes
1795 /// `feerate_per_kw` as an input such that multiple copies of a justice transaction at different
1796 /// fee rates may be built.
1797 pub fn build_to_local_justice_tx(&self, feerate_per_kw: u64, destination_script: Script)
1798 -> Result<Transaction, ()> {
1799 let output_idx = self.revokeable_output_index().ok_or(())?;
1800 let input = vec![TxIn {
1801 previous_output: OutPoint {
1802 txid: self.trust().txid(),
1803 vout: output_idx as u32,
1805 script_sig: Script::new(),
1806 sequence: Sequence::ENABLE_RBF_NO_LOCKTIME,
1807 witness: Witness::new(),
1809 let value = self.inner.built.transaction.output[output_idx].value;
1810 let output = vec![TxOut {
1811 script_pubkey: destination_script,
1814 let mut justice_tx = Transaction {
1816 lock_time: PackedLockTime::ZERO,
1820 let weight = justice_tx.weight() as u64 + WEIGHT_REVOKED_OUTPUT;
1821 let fee = fee_for_weight(feerate_per_kw as u32, weight);
1822 justice_tx.output[0].value = value.checked_sub(fee).ok_or(())?;
1828 /// Commitment transaction numbers which appear in the transactions themselves are XOR'd with a
1829 /// shared secret first. This prevents on-chain observers from discovering how many commitment
1830 /// transactions occurred in a channel before it was closed.
1832 /// This function gets the shared secret from relevant channel public keys and can be used to
1833 /// "decrypt" the commitment transaction number given a commitment transaction on-chain.
1834 pub fn get_commitment_transaction_number_obscure_factor(
1835 broadcaster_payment_basepoint: &PublicKey,
1836 countersignatory_payment_basepoint: &PublicKey,
1837 outbound_from_broadcaster: bool,
1839 let mut sha = Sha256::engine();
1841 if outbound_from_broadcaster {
1842 sha.input(&broadcaster_payment_basepoint.serialize());
1843 sha.input(&countersignatory_payment_basepoint.serialize());
1845 sha.input(&countersignatory_payment_basepoint.serialize());
1846 sha.input(&broadcaster_payment_basepoint.serialize());
1848 let res = Sha256::from_engine(sha).into_inner();
1850 ((res[26] as u64) << 5 * 8)
1851 | ((res[27] as u64) << 4 * 8)
1852 | ((res[28] as u64) << 3 * 8)
1853 | ((res[29] as u64) << 2 * 8)
1854 | ((res[30] as u64) << 1 * 8)
1855 | ((res[31] as u64) << 0 * 8)
1860 use super::{CounterpartyCommitmentSecrets, ChannelPublicKeys};
1861 use crate::{hex, chain};
1862 use crate::prelude::*;
1863 use crate::ln::chan_utils::{get_htlc_redeemscript, get_to_countersignatory_with_anchors_redeemscript, CommitmentTransaction, TxCreationKeys, ChannelTransactionParameters, CounterpartyChannelTransactionParameters, HTLCOutputInCommitment};
1864 use bitcoin::secp256k1::{PublicKey, SecretKey, Secp256k1};
1865 use crate::util::test_utils;
1866 use crate::sign::{ChannelSigner, SignerProvider};
1867 use bitcoin::{Network, Txid, Script};
1868 use bitcoin::hashes::Hash;
1869 use crate::ln::PaymentHash;
1870 use bitcoin::hashes::hex::ToHex;
1871 use bitcoin::util::address::Payload;
1872 use bitcoin::PublicKey as BitcoinPublicKey;
1873 use crate::ln::features::ChannelTypeFeatures;
1875 struct TestCommitmentTxBuilder {
1876 commitment_number: u64,
1877 holder_funding_pubkey: PublicKey,
1878 counterparty_funding_pubkey: PublicKey,
1879 keys: TxCreationKeys,
1880 feerate_per_kw: u32,
1881 htlcs_with_aux: Vec<(HTLCOutputInCommitment, ())>,
1882 channel_parameters: ChannelTransactionParameters,
1883 counterparty_pubkeys: ChannelPublicKeys,
1886 impl TestCommitmentTxBuilder {
1888 let secp_ctx = Secp256k1::new();
1889 let seed = [42; 32];
1890 let network = Network::Testnet;
1891 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
1892 let signer = keys_provider.derive_channel_signer(3000, keys_provider.generate_channel_keys_id(false, 1_000_000, 0));
1893 let counterparty_signer = keys_provider.derive_channel_signer(3000, keys_provider.generate_channel_keys_id(true, 1_000_000, 1));
1894 let delayed_payment_base = &signer.pubkeys().delayed_payment_basepoint;
1895 let per_commitment_secret = SecretKey::from_slice(&hex::decode("1f1e1d1c1b1a191817161514131211100f0e0d0c0b0a09080706050403020100").unwrap()[..]).unwrap();
1896 let per_commitment_point = PublicKey::from_secret_key(&secp_ctx, &per_commitment_secret);
1897 let htlc_basepoint = &signer.pubkeys().htlc_basepoint;
1898 let holder_pubkeys = signer.pubkeys();
1899 let counterparty_pubkeys = counterparty_signer.pubkeys().clone();
1900 let keys = TxCreationKeys::derive_new(&secp_ctx, &per_commitment_point, delayed_payment_base, htlc_basepoint, &counterparty_pubkeys.revocation_basepoint, &counterparty_pubkeys.htlc_basepoint);
1901 let channel_parameters = ChannelTransactionParameters {
1902 holder_pubkeys: holder_pubkeys.clone(),
1903 holder_selected_contest_delay: 0,
1904 is_outbound_from_holder: false,
1905 counterparty_parameters: Some(CounterpartyChannelTransactionParameters { pubkeys: counterparty_pubkeys.clone(), selected_contest_delay: 0 }),
1906 funding_outpoint: Some(chain::transaction::OutPoint { txid: Txid::all_zeros(), index: 0 }),
1907 channel_type_features: ChannelTypeFeatures::only_static_remote_key(),
1909 let htlcs_with_aux = Vec::new();
1912 commitment_number: 0,
1913 holder_funding_pubkey: holder_pubkeys.funding_pubkey,
1914 counterparty_funding_pubkey: counterparty_pubkeys.funding_pubkey,
1919 counterparty_pubkeys,
1923 fn build(&mut self, to_broadcaster_sats: u64, to_countersignatory_sats: u64) -> CommitmentTransaction {
1924 CommitmentTransaction::new_with_auxiliary_htlc_data(
1925 self.commitment_number, to_broadcaster_sats, to_countersignatory_sats,
1926 self.holder_funding_pubkey.clone(),
1927 self.counterparty_funding_pubkey.clone(),
1928 self.keys.clone(), self.feerate_per_kw,
1929 &mut self.htlcs_with_aux, &self.channel_parameters.as_holder_broadcastable()
1936 let mut builder = TestCommitmentTxBuilder::new();
1938 // Generate broadcaster and counterparty outputs
1939 let tx = builder.build(1000, 2000);
1940 assert_eq!(tx.built.transaction.output.len(), 2);
1941 assert_eq!(tx.built.transaction.output[1].script_pubkey, Payload::p2wpkh(&BitcoinPublicKey::new(builder.counterparty_pubkeys.payment_point)).unwrap().script_pubkey());
1943 // Generate broadcaster and counterparty outputs as well as two anchors
1944 builder.channel_parameters.channel_type_features = ChannelTypeFeatures::anchors_zero_htlc_fee_and_dependencies();
1945 let tx = builder.build(1000, 2000);
1946 assert_eq!(tx.built.transaction.output.len(), 4);
1947 assert_eq!(tx.built.transaction.output[3].script_pubkey, get_to_countersignatory_with_anchors_redeemscript(&builder.counterparty_pubkeys.payment_point).to_v0_p2wsh());
1949 // Generate broadcaster output and anchor
1950 let tx = builder.build(3000, 0);
1951 assert_eq!(tx.built.transaction.output.len(), 2);
1953 // Generate counterparty output and anchor
1954 let tx = builder.build(0, 3000);
1955 assert_eq!(tx.built.transaction.output.len(), 2);
1957 let received_htlc = HTLCOutputInCommitment {
1959 amount_msat: 400000,
1961 payment_hash: PaymentHash([42; 32]),
1962 transaction_output_index: None,
1965 let offered_htlc = HTLCOutputInCommitment {
1967 amount_msat: 600000,
1969 payment_hash: PaymentHash([43; 32]),
1970 transaction_output_index: None,
1973 // Generate broadcaster output and received and offered HTLC outputs, w/o anchors
1974 builder.channel_parameters.channel_type_features = ChannelTypeFeatures::only_static_remote_key();
1975 builder.htlcs_with_aux = vec![(received_htlc.clone(), ()), (offered_htlc.clone(), ())];
1976 let tx = builder.build(3000, 0);
1977 let keys = &builder.keys.clone();
1978 assert_eq!(tx.built.transaction.output.len(), 3);
1979 assert_eq!(tx.built.transaction.output[0].script_pubkey, get_htlc_redeemscript(&received_htlc, &ChannelTypeFeatures::only_static_remote_key(), &keys).to_v0_p2wsh());
1980 assert_eq!(tx.built.transaction.output[1].script_pubkey, get_htlc_redeemscript(&offered_htlc, &ChannelTypeFeatures::only_static_remote_key(), &keys).to_v0_p2wsh());
1981 assert_eq!(get_htlc_redeemscript(&received_htlc, &ChannelTypeFeatures::only_static_remote_key(), &keys).to_v0_p2wsh().to_hex(),
1982 "0020e43a7c068553003fe68fcae424fb7b28ec5ce48cd8b6744b3945631389bad2fb");
1983 assert_eq!(get_htlc_redeemscript(&offered_htlc, &ChannelTypeFeatures::only_static_remote_key(), &keys).to_v0_p2wsh().to_hex(),
1984 "0020215d61bba56b19e9eadb6107f5a85d7f99c40f65992443f69229c290165bc00d");
1986 // Generate broadcaster output and received and offered HTLC outputs, with anchors
1987 builder.channel_parameters.channel_type_features = ChannelTypeFeatures::anchors_zero_htlc_fee_and_dependencies();
1988 builder.htlcs_with_aux = vec![(received_htlc.clone(), ()), (offered_htlc.clone(), ())];
1989 let tx = builder.build(3000, 0);
1990 assert_eq!(tx.built.transaction.output.len(), 5);
1991 assert_eq!(tx.built.transaction.output[2].script_pubkey, get_htlc_redeemscript(&received_htlc, &ChannelTypeFeatures::anchors_zero_htlc_fee_and_dependencies(), &keys).to_v0_p2wsh());
1992 assert_eq!(tx.built.transaction.output[3].script_pubkey, get_htlc_redeemscript(&offered_htlc, &ChannelTypeFeatures::anchors_zero_htlc_fee_and_dependencies(), &keys).to_v0_p2wsh());
1993 assert_eq!(get_htlc_redeemscript(&received_htlc, &ChannelTypeFeatures::anchors_zero_htlc_fee_and_dependencies(), &keys).to_v0_p2wsh().to_hex(),
1994 "0020b70d0649c72b38756885c7a30908d912a7898dd5d79457a7280b8e9a20f3f2bc");
1995 assert_eq!(get_htlc_redeemscript(&offered_htlc, &ChannelTypeFeatures::anchors_zero_htlc_fee_and_dependencies(), &keys).to_v0_p2wsh().to_hex(),
1996 "002087a3faeb1950a469c0e2db4a79b093a41b9526e5a6fc6ef5cb949bde3be379c7");
2000 fn test_finding_revokeable_output_index() {
2001 let mut builder = TestCommitmentTxBuilder::new();
2003 // Revokeable output present
2004 let tx = builder.build(1000, 2000);
2005 assert_eq!(tx.built.transaction.output.len(), 2);
2006 assert_eq!(tx.trust().revokeable_output_index(), Some(0));
2008 // Revokeable output present (but to_broadcaster_delay missing)
2009 let tx = CommitmentTransaction { to_broadcaster_delay: None, ..tx };
2010 assert_eq!(tx.built.transaction.output.len(), 2);
2011 assert_eq!(tx.trust().revokeable_output_index(), None);
2013 // Revokeable output not present (our balance is dust)
2014 let tx = builder.build(0, 2000);
2015 assert_eq!(tx.built.transaction.output.len(), 1);
2016 assert_eq!(tx.trust().revokeable_output_index(), None);
2020 fn test_building_to_local_justice_tx() {
2021 let mut builder = TestCommitmentTxBuilder::new();
2023 // Revokeable output not present (our balance is dust)
2024 let tx = builder.build(0, 2000);
2025 assert_eq!(tx.built.transaction.output.len(), 1);
2026 assert!(tx.trust().build_to_local_justice_tx(253, Script::new()).is_err());
2028 // Revokeable output present
2029 let tx = builder.build(1000, 2000);
2030 assert_eq!(tx.built.transaction.output.len(), 2);
2033 assert!(tx.trust().build_to_local_justice_tx(100_000, Script::new()).is_err());
2035 // Generate a random public key for destination script
2036 let secret_key = SecretKey::from_slice(
2037 &hex::decode("1f1e1d1c1b1a191817161514131211100f0e0d0c0b0a09080706050403020100")
2038 .unwrap()[..]).unwrap();
2039 let pubkey_hash = BitcoinPublicKey::new(
2040 PublicKey::from_secret_key(&Secp256k1::new(), &secret_key)).wpubkey_hash().unwrap();
2041 let destination_script = Script::new_v0_p2wpkh(&pubkey_hash);
2043 let justice_tx = tx.trust().build_to_local_justice_tx(253, destination_script.clone()).unwrap();
2044 assert_eq!(justice_tx.input.len(), 1);
2045 assert_eq!(justice_tx.input[0].previous_output.txid, tx.built.transaction.txid());
2046 assert_eq!(justice_tx.input[0].previous_output.vout, tx.trust().revokeable_output_index().unwrap() as u32);
2047 assert!(justice_tx.input[0].sequence.is_rbf());
2049 assert_eq!(justice_tx.output.len(), 1);
2050 assert!(justice_tx.output[0].value < 1000);
2051 assert_eq!(justice_tx.output[0].script_pubkey, destination_script);
2055 fn test_per_commitment_storage() {
2056 // Test vectors from BOLT 3:
2057 let mut secrets: Vec<[u8; 32]> = Vec::new();
2060 macro_rules! test_secrets {
2062 let mut idx = 281474976710655;
2063 for secret in secrets.iter() {
2064 assert_eq!(monitor.get_secret(idx).unwrap(), *secret);
2067 assert_eq!(monitor.get_min_seen_secret(), idx + 1);
2068 assert!(monitor.get_secret(idx).is_none());
2073 // insert_secret correct sequence
2074 monitor = CounterpartyCommitmentSecrets::new();
2077 secrets.push([0; 32]);
2078 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2079 monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2082 secrets.push([0; 32]);
2083 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2084 monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2087 secrets.push([0; 32]);
2088 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2089 monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2092 secrets.push([0; 32]);
2093 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2094 monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
2097 secrets.push([0; 32]);
2098 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
2099 monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
2102 secrets.push([0; 32]);
2103 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
2104 monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
2107 secrets.push([0; 32]);
2108 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
2109 monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
2112 secrets.push([0; 32]);
2113 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
2114 monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap();
2119 // insert_secret #1 incorrect
2120 monitor = CounterpartyCommitmentSecrets::new();
2123 secrets.push([0; 32]);
2124 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
2125 monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2128 secrets.push([0; 32]);
2129 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2130 assert!(monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).is_err());
2134 // insert_secret #2 incorrect (#1 derived from incorrect)
2135 monitor = CounterpartyCommitmentSecrets::new();
2138 secrets.push([0; 32]);
2139 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
2140 monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2143 secrets.push([0; 32]);
2144 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("dddc3a8d14fddf2b68fa8c7fbad2748274937479dd0f8930d5ebb4ab6bd866a3").unwrap());
2145 monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2148 secrets.push([0; 32]);
2149 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2150 monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2153 secrets.push([0; 32]);
2154 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2155 assert!(monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).is_err());
2159 // insert_secret #3 incorrect
2160 monitor = CounterpartyCommitmentSecrets::new();
2163 secrets.push([0; 32]);
2164 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2165 monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2168 secrets.push([0; 32]);
2169 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2170 monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2173 secrets.push([0; 32]);
2174 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c51a18b13e8527e579ec56365482c62f180b7d5760b46e9477dae59e87ed423a").unwrap());
2175 monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2178 secrets.push([0; 32]);
2179 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2180 assert!(monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).is_err());
2184 // insert_secret #4 incorrect (1,2,3 derived from incorrect)
2185 monitor = CounterpartyCommitmentSecrets::new();
2188 secrets.push([0; 32]);
2189 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
2190 monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2193 secrets.push([0; 32]);
2194 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("dddc3a8d14fddf2b68fa8c7fbad2748274937479dd0f8930d5ebb4ab6bd866a3").unwrap());
2195 monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2198 secrets.push([0; 32]);
2199 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c51a18b13e8527e579ec56365482c62f180b7d5760b46e9477dae59e87ed423a").unwrap());
2200 monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2203 secrets.push([0; 32]);
2204 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("ba65d7b0ef55a3ba300d4e87af29868f394f8f138d78a7011669c79b37b936f4").unwrap());
2205 monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
2208 secrets.push([0; 32]);
2209 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
2210 monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
2213 secrets.push([0; 32]);
2214 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
2215 monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
2218 secrets.push([0; 32]);
2219 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
2220 monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
2223 secrets.push([0; 32]);
2224 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
2225 assert!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).is_err());
2229 // insert_secret #5 incorrect
2230 monitor = CounterpartyCommitmentSecrets::new();
2233 secrets.push([0; 32]);
2234 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2235 monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2238 secrets.push([0; 32]);
2239 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2240 monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2243 secrets.push([0; 32]);
2244 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2245 monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2248 secrets.push([0; 32]);
2249 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2250 monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
2253 secrets.push([0; 32]);
2254 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("631373ad5f9ef654bb3dade742d09504c567edd24320d2fcd68e3cc47e2ff6a6").unwrap());
2255 monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
2258 secrets.push([0; 32]);
2259 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
2260 assert!(monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).is_err());
2264 // insert_secret #6 incorrect (5 derived from incorrect)
2265 monitor = CounterpartyCommitmentSecrets::new();
2268 secrets.push([0; 32]);
2269 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2270 monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2273 secrets.push([0; 32]);
2274 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2275 monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2278 secrets.push([0; 32]);
2279 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2280 monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2283 secrets.push([0; 32]);
2284 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2285 monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
2288 secrets.push([0; 32]);
2289 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("631373ad5f9ef654bb3dade742d09504c567edd24320d2fcd68e3cc47e2ff6a6").unwrap());
2290 monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
2293 secrets.push([0; 32]);
2294 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("b7e76a83668bde38b373970155c868a653304308f9896692f904a23731224bb1").unwrap());
2295 monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
2298 secrets.push([0; 32]);
2299 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
2300 monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
2303 secrets.push([0; 32]);
2304 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
2305 assert!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).is_err());
2309 // insert_secret #7 incorrect
2310 monitor = CounterpartyCommitmentSecrets::new();
2313 secrets.push([0; 32]);
2314 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2315 monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2318 secrets.push([0; 32]);
2319 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2320 monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2323 secrets.push([0; 32]);
2324 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2325 monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2328 secrets.push([0; 32]);
2329 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2330 monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
2333 secrets.push([0; 32]);
2334 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
2335 monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
2338 secrets.push([0; 32]);
2339 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
2340 monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
2343 secrets.push([0; 32]);
2344 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("e7971de736e01da8ed58b94c2fc216cb1dca9e326f3a96e7194fe8ea8af6c0a3").unwrap());
2345 monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
2348 secrets.push([0; 32]);
2349 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
2350 assert!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).is_err());
2354 // insert_secret #8 incorrect
2355 monitor = CounterpartyCommitmentSecrets::new();
2358 secrets.push([0; 32]);
2359 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2360 monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2363 secrets.push([0; 32]);
2364 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2365 monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2368 secrets.push([0; 32]);
2369 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2370 monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2373 secrets.push([0; 32]);
2374 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2375 monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
2378 secrets.push([0; 32]);
2379 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
2380 monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
2383 secrets.push([0; 32]);
2384 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
2385 monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
2388 secrets.push([0; 32]);
2389 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
2390 monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
2393 secrets.push([0; 32]);
2394 secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a7efbc61aac46d34f77778bac22c8a20c6a46ca460addc49009bda875ec88fa4").unwrap());
2395 assert!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).is_err());