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Merge pull request #2248 from TheBlueMatt/2023-04-gossip-check
[rust-lightning] / lightning / src / ln / chan_utils.rs
1 // This file is Copyright its original authors, visible in version control
2 // history.
3 //
4 // This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
5 // or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
6 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
7 // You may not use this file except in accordance with one or both of these
8 // licenses.
9
10 //! 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.
12
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;
18
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};
23
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;
31
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;
36
37 use crate::io;
38 use crate::prelude::*;
39 use core::cmp;
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};
43 use core::ops::Deref;
44 use crate::chain;
45 use crate::ln::features::ChannelTypeFeatures;
46 use crate::util::crypto::{sign, sign_with_aux_rand};
47
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;
54
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;
62
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
66 /// outputs.
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
69 /// outputs.
70 pub const HTLC_SUCCESS_INPUT_ANCHOR_WITNESS_WEIGHT: u64 = 327;
71
72 /// Gets the weight for an HTLC-Success transaction.
73 #[inline]
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 }
78 }
79
80 /// Gets the weight for an HTLC-Timeout transaction.
81 #[inline]
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 }
86 }
87
88 /// Describes the type of HTLC claim as determined by analyzing the witness.
89 #[derive(PartialEq, Eq)]
90 pub enum HTLCClaim {
91         /// Claims an offered output on a commitment transaction through the timeout path.
92         OfferedTimeout,
93         /// Claims an offered output on a commitment transaction through the success path.
94         OfferedPreimage,
95         /// Claims an accepted output on a commitment transaction through the timeout path.
96         AcceptedTimeout,
97         /// Claims an accepted output on a commitment transaction through the success path.
98         AcceptedPreimage,
99         /// Claims an offered/accepted output on a commitment transaction through the revocation path.
100         Revocation,
101 }
102
103 impl HTLCClaim {
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 {
108                         return None;
109                 }
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)
122                         } else {
123                                 None
124                         }
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)
143                         } else {
144                                 None
145                         }
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)
158                         } else {
159                                 None
160                         }
161                 } else {
162                         None
163                 }
164         }
165 }
166
167 // Various functions for key derivation and transaction creation for use within channels. Primarily
168 // used in Channel and ChannelMonitor.
169
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();
173         for i in 0..48 {
174                 let bitpos = 47 - i;
175                 if idx & (1 << bitpos) == (1 << bitpos) {
176                         res[bitpos / 8] ^= 1 << (bitpos & 7);
177                         res = Sha256::hash(&res).into_inner();
178                 }
179         }
180         res
181 }
182
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 {
185         let txins = {
186                 let mut ins: Vec<TxIn> = Vec::new();
187                 ins.push(TxIn {
188                         previous_output: funding_outpoint,
189                         script_sig: Script::new(),
190                         sequence: Sequence::MAX,
191                         witness: Witness::new(),
192                 });
193                 ins
194         };
195
196         let mut txouts: Vec<(TxOut, ())> = Vec::new();
197
198         if to_counterparty_value_sat > 0 {
199                 txouts.push((TxOut {
200                         script_pubkey: to_counterparty_script,
201                         value: to_counterparty_value_sat
202                 }, ()));
203         }
204
205         if to_holder_value_sat > 0 {
206                 txouts.push((TxOut {
207                         script_pubkey: to_holder_script,
208                         value: to_holder_value_sat
209                 }, ()));
210         }
211
212         transaction_utils::sort_outputs(&mut txouts, |_, _| { cmp::Ordering::Equal }); // Ordering doesnt matter if they used our pubkey...
213
214         let mut outputs: Vec<TxOut> = Vec::new();
215         for out in txouts.drain(..) {
216                 outputs.push(out.0);
217         }
218
219         Transaction {
220                 version: 2,
221                 lock_time: PackedLockTime::ZERO,
222                 input: txins,
223                 output: outputs,
224         }
225 }
226
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).
229 ///
230 /// Allows us to keep track of all of the revocation secrets of our counterparty in just 50*32 bytes
231 /// or so.
232 #[derive(Clone)]
233 pub struct CounterpartyCommitmentSecrets {
234         old_secrets: [([u8; 32], u64); 49],
235 }
236
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 {
242                                 return false
243                         }
244                 }
245                 true
246         }
247 }
248
249 impl CounterpartyCommitmentSecrets {
250         /// Creates a new empty `CounterpartyCommitmentSecrets` structure.
251         pub fn new() -> Self {
252                 Self { old_secrets: [([0; 32], 1 << 48); 49], }
253         }
254
255         #[inline]
256         fn place_secret(idx: u64) -> u8 {
257                 for i in 0..48 {
258                         if idx & (1 << i) == (1 << i) {
259                                 return i
260                         }
261                 }
262                 48
263         }
264
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() {
271                         if idx < min {
272                                 min = idx;
273                         }
274                 }
275                 min
276         }
277
278         #[inline]
279         fn derive_secret(secret: [u8; 32], bits: u8, idx: u64) -> [u8; 32] {
280                 let mut res: [u8; 32] = secret;
281                 for i in 0..bits {
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();
286                         }
287                 }
288                 res
289         }
290
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);
295                 for i in 0..pos {
296                         let (old_secret, old_idx) = self.old_secrets[i as usize];
297                         if Self::derive_secret(secret, pos, old_idx) != old_secret {
298                                 return Err(());
299                         }
300                 }
301                 if self.get_min_seen_secret() <= idx {
302                         return Ok(());
303                 }
304                 self.old_secrets[pos as usize] = (secret, idx);
305                 Ok(())
306         }
307
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))
314                         }
315                 }
316                 assert!(idx < self.get_min_seen_secret());
317                 None
318         }
319 }
320
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())?;
326                 }
327                 write_tlv_fields!(writer, {});
328                 Ok(())
329         }
330 }
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)?;
337                 }
338                 read_tlv_fields!(reader, {});
339                 Ok(Self { old_secrets })
340         }
341 }
342
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();
350
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.")
353 }
354
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();
363
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.")
368 }
369
370 /// Derives a per-commitment-transaction revocation key from its constituent parts.
371 ///
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)
378 -> 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);
381
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());
386
387                 Sha256::from_engine(sha).into_inner()
388         };
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());
393
394                 Sha256::from_engine(sha).into_inner()
395         };
396
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.")
403 }
404
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.
408 ///
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.
413 ///
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)
418 -> 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());
423
424                 Sha256::from_engine(sha).into_inner()
425         };
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());
430
431                 Sha256::from_engine(sha).into_inner()
432         };
433
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.")
440 }
441
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.
444 ///
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
447 /// transaction.
448 ///
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)]
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
459         /// an old state.
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,
467 }
468
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),
475 });
476
477 /// One counterparty's public keys which do not change over the life of a channel.
478 #[derive(Clone, Debug, 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
486         /// states.
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,
499 }
500
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),
507 });
508
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 {
513                 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),
519                 }
520         }
521
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(
526                         &secp_ctx,
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,
532                 )
533         }
534 }
535
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;
540
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)
554                       .into_script();
555         debug_assert!(res.len() <= REVOKEABLE_REDEEMSCRIPT_MAX_LENGTH);
556         res
557 }
558
559 /// Information about an HTLC as it appears in a commitment transaction
560 #[derive(Clone, Debug, PartialEq, Eq)]
561 pub struct HTLCOutputInCommitment {
562         /// Whether the HTLC was "offered" (ie outbound in relation to this commitment transaction).
563         /// Note that this is not the same as whether it is ountbound *from us*. To determine that you
564         /// need to compare this value to whether the commitment transaction in question is that of
565         /// the counterparty or our own.
566         pub offered: bool,
567         /// The value, in msat, of the HTLC. The value as it appears in the commitment transaction is
568         /// this divided by 1000.
569         pub amount_msat: u64,
570         /// The CLTV lock-time at which this HTLC expires.
571         pub cltv_expiry: u32,
572         /// The hash of the preimage which unlocks this HTLC.
573         pub payment_hash: PaymentHash,
574         /// The position within the commitment transactions' outputs. This may be None if the value is
575         /// below the dust limit (in which case no output appears in the commitment transaction and the
576         /// value is spent to additional transaction fees).
577         pub transaction_output_index: Option<u32>,
578 }
579
580 impl_writeable_tlv_based!(HTLCOutputInCommitment, {
581         (0, offered, required),
582         (2, amount_msat, required),
583         (4, cltv_expiry, required),
584         (6, payment_hash, required),
585         (8, transaction_output_index, option),
586 });
587
588 #[inline]
589 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 {
590         let payment_hash160 = Ripemd160::hash(&htlc.payment_hash.0[..]).into_inner();
591         if htlc.offered {
592                 let mut bldr = Builder::new().push_opcode(opcodes::all::OP_DUP)
593                               .push_opcode(opcodes::all::OP_HASH160)
594                               .push_slice(&PubkeyHash::hash(&revocation_key.serialize())[..])
595                               .push_opcode(opcodes::all::OP_EQUAL)
596                               .push_opcode(opcodes::all::OP_IF)
597                               .push_opcode(opcodes::all::OP_CHECKSIG)
598                               .push_opcode(opcodes::all::OP_ELSE)
599                               .push_slice(&countersignatory_htlc_key.serialize()[..])
600                               .push_opcode(opcodes::all::OP_SWAP)
601                               .push_opcode(opcodes::all::OP_SIZE)
602                               .push_int(32)
603                               .push_opcode(opcodes::all::OP_EQUAL)
604                               .push_opcode(opcodes::all::OP_NOTIF)
605                               .push_opcode(opcodes::all::OP_DROP)
606                               .push_int(2)
607                               .push_opcode(opcodes::all::OP_SWAP)
608                               .push_slice(&broadcaster_htlc_key.serialize()[..])
609                               .push_int(2)
610                               .push_opcode(opcodes::all::OP_CHECKMULTISIG)
611                               .push_opcode(opcodes::all::OP_ELSE)
612                               .push_opcode(opcodes::all::OP_HASH160)
613                               .push_slice(&payment_hash160)
614                               .push_opcode(opcodes::all::OP_EQUALVERIFY)
615                               .push_opcode(opcodes::all::OP_CHECKSIG)
616                               .push_opcode(opcodes::all::OP_ENDIF);
617                 if channel_type_features.supports_anchors_zero_fee_htlc_tx() {
618                         bldr = bldr.push_opcode(opcodes::all::OP_PUSHNUM_1)
619                                 .push_opcode(opcodes::all::OP_CSV)
620                                 .push_opcode(opcodes::all::OP_DROP);
621                 }
622                 bldr.push_opcode(opcodes::all::OP_ENDIF)
623                         .into_script()
624         } else {
625                         let mut bldr = Builder::new().push_opcode(opcodes::all::OP_DUP)
626                               .push_opcode(opcodes::all::OP_HASH160)
627                               .push_slice(&PubkeyHash::hash(&revocation_key.serialize())[..])
628                               .push_opcode(opcodes::all::OP_EQUAL)
629                               .push_opcode(opcodes::all::OP_IF)
630                               .push_opcode(opcodes::all::OP_CHECKSIG)
631                               .push_opcode(opcodes::all::OP_ELSE)
632                               .push_slice(&countersignatory_htlc_key.serialize()[..])
633                               .push_opcode(opcodes::all::OP_SWAP)
634                               .push_opcode(opcodes::all::OP_SIZE)
635                               .push_int(32)
636                               .push_opcode(opcodes::all::OP_EQUAL)
637                               .push_opcode(opcodes::all::OP_IF)
638                               .push_opcode(opcodes::all::OP_HASH160)
639                               .push_slice(&payment_hash160)
640                               .push_opcode(opcodes::all::OP_EQUALVERIFY)
641                               .push_int(2)
642                               .push_opcode(opcodes::all::OP_SWAP)
643                               .push_slice(&broadcaster_htlc_key.serialize()[..])
644                               .push_int(2)
645                               .push_opcode(opcodes::all::OP_CHECKMULTISIG)
646                               .push_opcode(opcodes::all::OP_ELSE)
647                               .push_opcode(opcodes::all::OP_DROP)
648                               .push_int(htlc.cltv_expiry as i64)
649                               .push_opcode(opcodes::all::OP_CLTV)
650                               .push_opcode(opcodes::all::OP_DROP)
651                               .push_opcode(opcodes::all::OP_CHECKSIG)
652                               .push_opcode(opcodes::all::OP_ENDIF);
653                 if channel_type_features.supports_anchors_zero_fee_htlc_tx() {
654                         bldr = bldr.push_opcode(opcodes::all::OP_PUSHNUM_1)
655                                 .push_opcode(opcodes::all::OP_CSV)
656                                 .push_opcode(opcodes::all::OP_DROP);
657                 }
658                 bldr.push_opcode(opcodes::all::OP_ENDIF)
659                         .into_script()
660         }
661 }
662
663 /// Gets the witness redeemscript for an HTLC output in a commitment transaction. Note that htlc
664 /// does not need to have its previous_output_index filled.
665 #[inline]
666 pub fn get_htlc_redeemscript(htlc: &HTLCOutputInCommitment, channel_type_features: &ChannelTypeFeatures, keys: &TxCreationKeys) -> Script {
667         get_htlc_redeemscript_with_explicit_keys(htlc, channel_type_features, &keys.broadcaster_htlc_key, &keys.countersignatory_htlc_key, &keys.revocation_key)
668 }
669
670 /// Gets the redeemscript for a funding output from the two funding public keys.
671 /// Note that the order of funding public keys does not matter.
672 pub fn make_funding_redeemscript(broadcaster: &PublicKey, countersignatory: &PublicKey) -> Script {
673         let broadcaster_funding_key = broadcaster.serialize();
674         let countersignatory_funding_key = countersignatory.serialize();
675
676         make_funding_redeemscript_from_slices(&broadcaster_funding_key, &countersignatory_funding_key)
677 }
678
679 pub(crate) fn make_funding_redeemscript_from_slices(broadcaster_funding_key: &[u8], countersignatory_funding_key: &[u8]) -> Script {
680         let builder = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2);
681         if broadcaster_funding_key[..] < countersignatory_funding_key[..] {
682                 builder.push_slice(broadcaster_funding_key)
683                         .push_slice(countersignatory_funding_key)
684         } else {
685                 builder.push_slice(countersignatory_funding_key)
686                         .push_slice(broadcaster_funding_key)
687         }.push_opcode(opcodes::all::OP_PUSHNUM_2).push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script()
688 }
689
690 /// Builds an unsigned HTLC-Success or HTLC-Timeout transaction from the given channel and HTLC
691 /// parameters. This is used by [`TrustedCommitmentTransaction::get_htlc_sigs`] to fetch the
692 /// transaction which needs signing, and can be used to construct an HTLC transaction which is
693 /// broadcastable given a counterparty HTLC signature.
694 ///
695 /// Panics if htlc.transaction_output_index.is_none() (as such HTLCs do not appear in the
696 /// commitment transaction).
697 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 {
698         let mut txins: Vec<TxIn> = Vec::new();
699         txins.push(build_htlc_input(commitment_txid, htlc, channel_type_features));
700
701         let mut txouts: Vec<TxOut> = Vec::new();
702         txouts.push(build_htlc_output(
703                 feerate_per_kw, contest_delay, htlc, channel_type_features,
704                 broadcaster_delayed_payment_key, revocation_key
705         ));
706
707         Transaction {
708                 version: 2,
709                 lock_time: PackedLockTime(if htlc.offered { htlc.cltv_expiry } else { 0 }),
710                 input: txins,
711                 output: txouts,
712         }
713 }
714
715 pub(crate) fn build_htlc_input(commitment_txid: &Txid, htlc: &HTLCOutputInCommitment, channel_type_features: &ChannelTypeFeatures) -> TxIn {
716         TxIn {
717                 previous_output: OutPoint {
718                         txid: commitment_txid.clone(),
719                         vout: htlc.transaction_output_index.expect("Can't build an HTLC transaction for a dust output"),
720                 },
721                 script_sig: Script::new(),
722                 sequence: Sequence(if channel_type_features.supports_anchors_zero_fee_htlc_tx() { 1 } else { 0 }),
723                 witness: Witness::new(),
724         }
725 }
726
727 pub(crate) fn build_htlc_output(
728         feerate_per_kw: u32, contest_delay: u16, htlc: &HTLCOutputInCommitment, channel_type_features: &ChannelTypeFeatures, broadcaster_delayed_payment_key: &PublicKey, revocation_key: &PublicKey
729 ) -> TxOut {
730         let weight = if htlc.offered {
731                 htlc_timeout_tx_weight(channel_type_features)
732         } else {
733                 htlc_success_tx_weight(channel_type_features)
734         };
735         let output_value = if channel_type_features.supports_anchors_zero_fee_htlc_tx() && !channel_type_features.supports_anchors_nonzero_fee_htlc_tx() {
736                 htlc.amount_msat / 1000
737         } else {
738                 let total_fee = feerate_per_kw as u64 * weight / 1000;
739                 htlc.amount_msat / 1000 - total_fee
740         };
741
742         TxOut {
743                 script_pubkey: get_revokeable_redeemscript(revocation_key, contest_delay, broadcaster_delayed_payment_key).to_v0_p2wsh(),
744                 value: output_value,
745         }
746 }
747
748 /// Returns the witness required to satisfy and spend a HTLC input.
749 pub fn build_htlc_input_witness(
750         local_sig: &Signature, remote_sig: &Signature, preimage: &Option<PaymentPreimage>,
751         redeem_script: &Script, channel_type_features: &ChannelTypeFeatures,
752 ) -> Witness {
753         let remote_sighash_type = if channel_type_features.supports_anchors_zero_fee_htlc_tx() {
754                 EcdsaSighashType::SinglePlusAnyoneCanPay
755         } else {
756                 EcdsaSighashType::All
757         };
758
759         let mut witness = Witness::new();
760         // First push the multisig dummy, note that due to BIP147 (NULLDUMMY) it must be a zero-length element.
761         witness.push(vec![]);
762         witness.push_bitcoin_signature(&remote_sig.serialize_der(), remote_sighash_type);
763         witness.push_bitcoin_signature(&local_sig.serialize_der(), EcdsaSighashType::All);
764         if let Some(preimage) = preimage {
765                 witness.push(preimage.0.to_vec());
766         } else {
767                 // Due to BIP146 (MINIMALIF) this must be a zero-length element to relay.
768                 witness.push(vec![]);
769         }
770         witness.push(redeem_script.to_bytes());
771         witness
772 }
773
774 /// Pre-anchors channel type features did not use to get serialized in the following six structs:
775 /// â€” [`ChannelTransactionParameters`]
776 /// â€” [`CommitmentTransaction`]
777 /// â€” [`CounterpartyOfferedHTLCOutput`]
778 /// â€” [`CounterpartyReceivedHTLCOutput`]
779 /// â€” [`HolderHTLCOutput`]
780 /// â€” [`HolderFundingOutput`]
781 ///
782 /// To ensure a forwards-compatible serialization, we use odd TLV fields. However, if new features
783 /// are used that could break security, where old signers should be prevented from handling the
784 /// serialized data, an optional even-field TLV will be used as a stand-in to break compatibility.
785 ///
786 /// This method determines whether or not that option needs to be set based on the chanenl type
787 /// features, and returns it.
788 ///
789 /// [`CounterpartyOfferedHTLCOutput`]: crate::chain::package::CounterpartyOfferedHTLCOutput
790 /// [`CounterpartyReceivedHTLCOutput`]: crate::chain::package::CounterpartyReceivedHTLCOutput
791 /// [`HolderHTLCOutput`]: crate::chain::package::HolderHTLCOutput
792 /// [`HolderFundingOutput`]: crate::chain::package::HolderFundingOutput
793 pub(crate) fn legacy_deserialization_prevention_marker_for_channel_type_features(features: &ChannelTypeFeatures) -> Option<()> {
794         let mut legacy_version_bit_set = ChannelTypeFeatures::only_static_remote_key();
795         legacy_version_bit_set.set_scid_privacy_required();
796         legacy_version_bit_set.set_zero_conf_required();
797
798         if features.is_subset(&legacy_version_bit_set) {
799                 None
800         } else {
801                 Some(())
802         }
803 }
804
805 /// Gets the witnessScript for the to_remote output when anchors are enabled.
806 #[inline]
807 pub fn get_to_countersignatory_with_anchors_redeemscript(payment_point: &PublicKey) -> Script {
808         Builder::new()
809                 .push_slice(&payment_point.serialize()[..])
810                 .push_opcode(opcodes::all::OP_CHECKSIGVERIFY)
811                 .push_int(1)
812                 .push_opcode(opcodes::all::OP_CSV)
813                 .into_script()
814 }
815
816 /// Gets the witnessScript for an anchor output from the funding public key.
817 /// The witness in the spending input must be:
818 /// <BIP 143 funding_signature>
819 /// After 16 blocks of confirmation, an alternative satisfying witness could be:
820 /// <>
821 /// (empty vector required to satisfy compliance with MINIMALIF-standard rule)
822 #[inline]
823 pub fn get_anchor_redeemscript(funding_pubkey: &PublicKey) -> Script {
824         Builder::new().push_slice(&funding_pubkey.serialize()[..])
825                 .push_opcode(opcodes::all::OP_CHECKSIG)
826                 .push_opcode(opcodes::all::OP_IFDUP)
827                 .push_opcode(opcodes::all::OP_NOTIF)
828                 .push_int(16)
829                 .push_opcode(opcodes::all::OP_CSV)
830                 .push_opcode(opcodes::all::OP_ENDIF)
831                 .into_script()
832 }
833
834 /// Locates the output with an anchor script paying to `funding_pubkey` within `commitment_tx`.
835 pub(crate) fn get_anchor_output<'a>(commitment_tx: &'a Transaction, funding_pubkey: &PublicKey) -> Option<(u32, &'a TxOut)> {
836         let anchor_script = chan_utils::get_anchor_redeemscript(funding_pubkey).to_v0_p2wsh();
837         commitment_tx.output.iter().enumerate()
838                 .find(|(_, txout)| txout.script_pubkey == anchor_script)
839                 .map(|(idx, txout)| (idx as u32, txout))
840 }
841
842 /// Returns the witness required to satisfy and spend an anchor input.
843 pub fn build_anchor_input_witness(funding_key: &PublicKey, funding_sig: &Signature) -> Witness {
844         let anchor_redeem_script = chan_utils::get_anchor_redeemscript(funding_key);
845         let mut ret = Witness::new();
846         ret.push_bitcoin_signature(&funding_sig.serialize_der(), EcdsaSighashType::All);
847         ret.push(anchor_redeem_script.as_bytes());
848         ret
849 }
850
851 /// Per-channel data used to build transactions in conjunction with the per-commitment data (CommitmentTransaction).
852 /// The fields are organized by holder/counterparty.
853 ///
854 /// Normally, this is converted to the broadcaster/countersignatory-organized DirectedChannelTransactionParameters
855 /// before use, via the as_holder_broadcastable and as_counterparty_broadcastable functions.
856 #[derive(Clone, Debug, PartialEq, Eq)]
857 pub struct ChannelTransactionParameters {
858         /// Holder public keys
859         pub holder_pubkeys: ChannelPublicKeys,
860         /// The contest delay selected by the holder, which applies to counterparty-broadcast transactions
861         pub holder_selected_contest_delay: u16,
862         /// Whether the holder is the initiator of this channel.
863         /// This is an input to the commitment number obscure factor computation.
864         pub is_outbound_from_holder: bool,
865         /// The late-bound counterparty channel transaction parameters.
866         /// These parameters are populated at the point in the protocol where the counterparty provides them.
867         pub counterparty_parameters: Option<CounterpartyChannelTransactionParameters>,
868         /// The late-bound funding outpoint
869         pub funding_outpoint: Option<chain::transaction::OutPoint>,
870         /// This channel's type, as negotiated during channel open. For old objects where this field
871         /// wasn't serialized, it will default to static_remote_key at deserialization.
872         pub channel_type_features: ChannelTypeFeatures
873 }
874
875 /// Late-bound per-channel counterparty data used to build transactions.
876 #[derive(Clone, Debug, PartialEq, Eq)]
877 pub struct CounterpartyChannelTransactionParameters {
878         /// Counter-party public keys
879         pub pubkeys: ChannelPublicKeys,
880         /// The contest delay selected by the counterparty, which applies to holder-broadcast transactions
881         pub selected_contest_delay: u16,
882 }
883
884 impl ChannelTransactionParameters {
885         /// Whether the late bound parameters are populated.
886         pub fn is_populated(&self) -> bool {
887                 self.counterparty_parameters.is_some() && self.funding_outpoint.is_some()
888         }
889
890         /// Convert the holder/counterparty parameters to broadcaster/countersignatory-organized parameters,
891         /// given that the holder is the broadcaster.
892         ///
893         /// self.is_populated() must be true before calling this function.
894         pub fn as_holder_broadcastable(&self) -> DirectedChannelTransactionParameters {
895                 assert!(self.is_populated(), "self.late_parameters must be set before using as_holder_broadcastable");
896                 DirectedChannelTransactionParameters {
897                         inner: self,
898                         holder_is_broadcaster: true
899                 }
900         }
901
902         /// Convert the holder/counterparty parameters to broadcaster/countersignatory-organized parameters,
903         /// given that the counterparty is the broadcaster.
904         ///
905         /// self.is_populated() must be true before calling this function.
906         pub fn as_counterparty_broadcastable(&self) -> DirectedChannelTransactionParameters {
907                 assert!(self.is_populated(), "self.late_parameters must be set before using as_counterparty_broadcastable");
908                 DirectedChannelTransactionParameters {
909                         inner: self,
910                         holder_is_broadcaster: false
911                 }
912         }
913 }
914
915 impl_writeable_tlv_based!(CounterpartyChannelTransactionParameters, {
916         (0, pubkeys, required),
917         (2, selected_contest_delay, required),
918 });
919
920 impl Writeable for ChannelTransactionParameters {
921         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
922                 let legacy_deserialization_prevention_marker = legacy_deserialization_prevention_marker_for_channel_type_features(&self.channel_type_features);
923                 write_tlv_fields!(writer, {
924                         (0, self.holder_pubkeys, required),
925                         (2, self.holder_selected_contest_delay, required),
926                         (4, self.is_outbound_from_holder, required),
927                         (6, self.counterparty_parameters, option),
928                         (8, self.funding_outpoint, option),
929                         (10, legacy_deserialization_prevention_marker, option),
930                         (11, self.channel_type_features, required),
931                 });
932                 Ok(())
933         }
934 }
935
936 impl Readable for ChannelTransactionParameters {
937         fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
938                 let mut holder_pubkeys = RequiredWrapper(None);
939                 let mut holder_selected_contest_delay = RequiredWrapper(None);
940                 let mut is_outbound_from_holder = RequiredWrapper(None);
941                 let mut counterparty_parameters = None;
942                 let mut funding_outpoint = None;
943                 let mut _legacy_deserialization_prevention_marker: Option<()> = None;
944                 let mut channel_type_features = None;
945
946                 read_tlv_fields!(reader, {
947                         (0, holder_pubkeys, required),
948                         (2, holder_selected_contest_delay, required),
949                         (4, is_outbound_from_holder, required),
950                         (6, counterparty_parameters, option),
951                         (8, funding_outpoint, option),
952                         (10, _legacy_deserialization_prevention_marker, option),
953                         (11, channel_type_features, option),
954                 });
955
956                 let mut additional_features = ChannelTypeFeatures::empty();
957                 additional_features.set_anchors_nonzero_fee_htlc_tx_required();
958                 chain::package::verify_channel_type_features(&channel_type_features, Some(&additional_features))?;
959
960                 Ok(Self {
961                         holder_pubkeys: holder_pubkeys.0.unwrap(),
962                         holder_selected_contest_delay: holder_selected_contest_delay.0.unwrap(),
963                         is_outbound_from_holder: is_outbound_from_holder.0.unwrap(),
964                         counterparty_parameters,
965                         funding_outpoint,
966                         channel_type_features: channel_type_features.unwrap_or(ChannelTypeFeatures::only_static_remote_key())
967                 })
968         }
969 }
970
971 /// Static channel fields used to build transactions given per-commitment fields, organized by
972 /// broadcaster/countersignatory.
973 ///
974 /// This is derived from the holder/counterparty-organized ChannelTransactionParameters via the
975 /// as_holder_broadcastable and as_counterparty_broadcastable functions.
976 pub struct DirectedChannelTransactionParameters<'a> {
977         /// The holder's channel static parameters
978         inner: &'a ChannelTransactionParameters,
979         /// Whether the holder is the broadcaster
980         holder_is_broadcaster: bool,
981 }
982
983 impl<'a> DirectedChannelTransactionParameters<'a> {
984         /// Get the channel pubkeys for the broadcaster
985         pub fn broadcaster_pubkeys(&self) -> &ChannelPublicKeys {
986                 if self.holder_is_broadcaster {
987                         &self.inner.holder_pubkeys
988                 } else {
989                         &self.inner.counterparty_parameters.as_ref().unwrap().pubkeys
990                 }
991         }
992
993         /// Get the channel pubkeys for the countersignatory
994         pub fn countersignatory_pubkeys(&self) -> &ChannelPublicKeys {
995                 if self.holder_is_broadcaster {
996                         &self.inner.counterparty_parameters.as_ref().unwrap().pubkeys
997                 } else {
998                         &self.inner.holder_pubkeys
999                 }
1000         }
1001
1002         /// Get the contest delay applicable to the transactions.
1003         /// Note that the contest delay was selected by the countersignatory.
1004         pub fn contest_delay(&self) -> u16 {
1005                 let counterparty_parameters = self.inner.counterparty_parameters.as_ref().unwrap();
1006                 if self.holder_is_broadcaster { counterparty_parameters.selected_contest_delay } else { self.inner.holder_selected_contest_delay }
1007         }
1008
1009         /// Whether the channel is outbound from the broadcaster.
1010         ///
1011         /// The boolean representing the side that initiated the channel is
1012         /// an input to the commitment number obscure factor computation.
1013         pub fn is_outbound(&self) -> bool {
1014                 if self.holder_is_broadcaster { self.inner.is_outbound_from_holder } else { !self.inner.is_outbound_from_holder }
1015         }
1016
1017         /// The funding outpoint
1018         pub fn funding_outpoint(&self) -> OutPoint {
1019                 self.inner.funding_outpoint.unwrap().into_bitcoin_outpoint()
1020         }
1021
1022         /// Whether to use anchors for this channel
1023         pub fn channel_type_features(&self) -> &ChannelTypeFeatures {
1024                 &self.inner.channel_type_features
1025         }
1026 }
1027
1028 /// Information needed to build and sign a holder's commitment transaction.
1029 ///
1030 /// The transaction is only signed once we are ready to broadcast.
1031 #[derive(Clone)]
1032 pub struct HolderCommitmentTransaction {
1033         inner: CommitmentTransaction,
1034         /// Our counterparty's signature for the transaction
1035         pub counterparty_sig: Signature,
1036         /// All non-dust counterparty HTLC signatures, in the order they appear in the transaction
1037         pub counterparty_htlc_sigs: Vec<Signature>,
1038         // Which order the signatures should go in when constructing the final commitment tx witness.
1039         // The user should be able to reconstruct this themselves, so we don't bother to expose it.
1040         holder_sig_first: bool,
1041 }
1042
1043 impl Deref for HolderCommitmentTransaction {
1044         type Target = CommitmentTransaction;
1045
1046         fn deref(&self) -> &Self::Target { &self.inner }
1047 }
1048
1049 impl Eq for HolderCommitmentTransaction {}
1050 impl PartialEq for HolderCommitmentTransaction {
1051         // We dont care whether we are signed in equality comparison
1052         fn eq(&self, o: &Self) -> bool {
1053                 self.inner == o.inner
1054         }
1055 }
1056
1057 impl_writeable_tlv_based!(HolderCommitmentTransaction, {
1058         (0, inner, required),
1059         (2, counterparty_sig, required),
1060         (4, holder_sig_first, required),
1061         (6, counterparty_htlc_sigs, required_vec),
1062 });
1063
1064 impl HolderCommitmentTransaction {
1065         #[cfg(test)]
1066         pub fn dummy(htlcs: &mut Vec<(HTLCOutputInCommitment, ())>) -> Self {
1067                 let secp_ctx = Secp256k1::new();
1068                 let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
1069                 let dummy_sig = sign(&secp_ctx, &secp256k1::Message::from_slice(&[42; 32]).unwrap(), &SecretKey::from_slice(&[42; 32]).unwrap());
1070
1071                 let keys = TxCreationKeys {
1072                         per_commitment_point: dummy_key.clone(),
1073                         revocation_key: dummy_key.clone(),
1074                         broadcaster_htlc_key: dummy_key.clone(),
1075                         countersignatory_htlc_key: dummy_key.clone(),
1076                         broadcaster_delayed_payment_key: dummy_key.clone(),
1077                 };
1078                 let channel_pubkeys = ChannelPublicKeys {
1079                         funding_pubkey: dummy_key.clone(),
1080                         revocation_basepoint: dummy_key.clone(),
1081                         payment_point: dummy_key.clone(),
1082                         delayed_payment_basepoint: dummy_key.clone(),
1083                         htlc_basepoint: dummy_key.clone()
1084                 };
1085                 let channel_parameters = ChannelTransactionParameters {
1086                         holder_pubkeys: channel_pubkeys.clone(),
1087                         holder_selected_contest_delay: 0,
1088                         is_outbound_from_holder: false,
1089                         counterparty_parameters: Some(CounterpartyChannelTransactionParameters { pubkeys: channel_pubkeys.clone(), selected_contest_delay: 0 }),
1090                         funding_outpoint: Some(chain::transaction::OutPoint { txid: Txid::all_zeros(), index: 0 }),
1091                         channel_type_features: ChannelTypeFeatures::only_static_remote_key(),
1092                 };
1093                 let mut counterparty_htlc_sigs = Vec::new();
1094                 for _ in 0..htlcs.len() {
1095                         counterparty_htlc_sigs.push(dummy_sig);
1096                 }
1097                 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());
1098                 htlcs.sort_by_key(|htlc| htlc.0.transaction_output_index);
1099                 HolderCommitmentTransaction {
1100                         inner,
1101                         counterparty_sig: dummy_sig,
1102                         counterparty_htlc_sigs,
1103                         holder_sig_first: false
1104                 }
1105         }
1106
1107         /// Create a new holder transaction with the given counterparty signatures.
1108         /// The funding keys are used to figure out which signature should go first when building the transaction for broadcast.
1109         pub fn new(commitment_tx: CommitmentTransaction, counterparty_sig: Signature, counterparty_htlc_sigs: Vec<Signature>, holder_funding_key: &PublicKey, counterparty_funding_key: &PublicKey) -> Self {
1110                 Self {
1111                         inner: commitment_tx,
1112                         counterparty_sig,
1113                         counterparty_htlc_sigs,
1114                         holder_sig_first: holder_funding_key.serialize()[..] < counterparty_funding_key.serialize()[..],
1115                 }
1116         }
1117
1118         pub(crate) fn add_holder_sig(&self, funding_redeemscript: &Script, holder_sig: Signature) -> Transaction {
1119                 // First push the multisig dummy, note that due to BIP147 (NULLDUMMY) it must be a zero-length element.
1120                 let mut tx = self.inner.built.transaction.clone();
1121                 tx.input[0].witness.push(Vec::new());
1122
1123                 if self.holder_sig_first {
1124                         tx.input[0].witness.push_bitcoin_signature(&holder_sig.serialize_der(), EcdsaSighashType::All);
1125                         tx.input[0].witness.push_bitcoin_signature(&self.counterparty_sig.serialize_der(), EcdsaSighashType::All);
1126                 } else {
1127                         tx.input[0].witness.push_bitcoin_signature(&self.counterparty_sig.serialize_der(), EcdsaSighashType::All);
1128                         tx.input[0].witness.push_bitcoin_signature(&holder_sig.serialize_der(), EcdsaSighashType::All);
1129                 }
1130
1131                 tx.input[0].witness.push(funding_redeemscript.as_bytes().to_vec());
1132                 tx
1133         }
1134 }
1135
1136 /// A pre-built Bitcoin commitment transaction and its txid.
1137 #[derive(Clone)]
1138 pub struct BuiltCommitmentTransaction {
1139         /// The commitment transaction
1140         pub transaction: Transaction,
1141         /// The txid for the commitment transaction.
1142         ///
1143         /// This is provided as a performance optimization, instead of calling transaction.txid()
1144         /// multiple times.
1145         pub txid: Txid,
1146 }
1147
1148 impl_writeable_tlv_based!(BuiltCommitmentTransaction, {
1149         (0, transaction, required),
1150         (2, txid, required),
1151 });
1152
1153 impl BuiltCommitmentTransaction {
1154         /// Get the SIGHASH_ALL sighash value of the transaction.
1155         ///
1156         /// This can be used to verify a signature.
1157         pub fn get_sighash_all(&self, funding_redeemscript: &Script, channel_value_satoshis: u64) -> Message {
1158                 let sighash = &sighash::SighashCache::new(&self.transaction).segwit_signature_hash(0, funding_redeemscript, channel_value_satoshis, EcdsaSighashType::All).unwrap()[..];
1159                 hash_to_message!(sighash)
1160         }
1161
1162         /// Signs the counterparty's commitment transaction.
1163         pub fn sign_counterparty_commitment<T: secp256k1::Signing>(&self, funding_key: &SecretKey, funding_redeemscript: &Script, channel_value_satoshis: u64, secp_ctx: &Secp256k1<T>) -> Signature {
1164                 let sighash = self.get_sighash_all(funding_redeemscript, channel_value_satoshis);
1165                 sign(secp_ctx, &sighash, funding_key)
1166         }
1167
1168         /// Signs the holder commitment transaction because we are about to broadcast it.
1169         pub fn sign_holder_commitment<T: secp256k1::Signing, ES: Deref>(
1170                 &self, funding_key: &SecretKey, funding_redeemscript: &Script, channel_value_satoshis: u64,
1171                 entropy_source: &ES, secp_ctx: &Secp256k1<T>
1172         ) -> Signature where ES::Target: EntropySource {
1173                 let sighash = self.get_sighash_all(funding_redeemscript, channel_value_satoshis);
1174                 sign_with_aux_rand(secp_ctx, &sighash, funding_key, entropy_source)
1175         }
1176 }
1177
1178 /// This class tracks the per-transaction information needed to build a closing transaction and will
1179 /// actually build it and sign.
1180 ///
1181 /// This class can be used inside a signer implementation to generate a signature given the relevant
1182 /// secret key.
1183 #[derive(Clone, Hash, PartialEq, Eq)]
1184 pub struct ClosingTransaction {
1185         to_holder_value_sat: u64,
1186         to_counterparty_value_sat: u64,
1187         to_holder_script: Script,
1188         to_counterparty_script: Script,
1189         built: Transaction,
1190 }
1191
1192 impl ClosingTransaction {
1193         /// Construct an object of the class
1194         pub fn new(
1195                 to_holder_value_sat: u64,
1196                 to_counterparty_value_sat: u64,
1197                 to_holder_script: Script,
1198                 to_counterparty_script: Script,
1199                 funding_outpoint: OutPoint,
1200         ) -> Self {
1201                 let built = build_closing_transaction(
1202                         to_holder_value_sat, to_counterparty_value_sat,
1203                         to_holder_script.clone(), to_counterparty_script.clone(),
1204                         funding_outpoint
1205                 );
1206                 ClosingTransaction {
1207                         to_holder_value_sat,
1208                         to_counterparty_value_sat,
1209                         to_holder_script,
1210                         to_counterparty_script,
1211                         built
1212                 }
1213         }
1214
1215         /// Trust our pre-built transaction.
1216         ///
1217         /// Applies a wrapper which allows access to the transaction.
1218         ///
1219         /// This should only be used if you fully trust the builder of this object. It should not
1220         /// be used by an external signer - instead use the verify function.
1221         pub fn trust(&self) -> TrustedClosingTransaction {
1222                 TrustedClosingTransaction { inner: self }
1223         }
1224
1225         /// Verify our pre-built transaction.
1226         ///
1227         /// Applies a wrapper which allows access to the transaction.
1228         ///
1229         /// An external validating signer must call this method before signing
1230         /// or using the built transaction.
1231         pub fn verify(&self, funding_outpoint: OutPoint) -> Result<TrustedClosingTransaction, ()> {
1232                 let built = build_closing_transaction(
1233                         self.to_holder_value_sat, self.to_counterparty_value_sat,
1234                         self.to_holder_script.clone(), self.to_counterparty_script.clone(),
1235                         funding_outpoint
1236                 );
1237                 if self.built != built {
1238                         return Err(())
1239                 }
1240                 Ok(TrustedClosingTransaction { inner: self })
1241         }
1242
1243         /// The value to be sent to the holder, or zero if the output will be omitted
1244         pub fn to_holder_value_sat(&self) -> u64 {
1245                 self.to_holder_value_sat
1246         }
1247
1248         /// The value to be sent to the counterparty, or zero if the output will be omitted
1249         pub fn to_counterparty_value_sat(&self) -> u64 {
1250                 self.to_counterparty_value_sat
1251         }
1252
1253         /// The destination of the holder's output
1254         pub fn to_holder_script(&self) -> &Script {
1255                 &self.to_holder_script
1256         }
1257
1258         /// The destination of the counterparty's output
1259         pub fn to_counterparty_script(&self) -> &Script {
1260                 &self.to_counterparty_script
1261         }
1262 }
1263
1264 /// A wrapper on ClosingTransaction indicating that the built bitcoin
1265 /// transaction is trusted.
1266 ///
1267 /// See trust() and verify() functions on CommitmentTransaction.
1268 ///
1269 /// This structure implements Deref.
1270 pub struct TrustedClosingTransaction<'a> {
1271         inner: &'a ClosingTransaction,
1272 }
1273
1274 impl<'a> Deref for TrustedClosingTransaction<'a> {
1275         type Target = ClosingTransaction;
1276
1277         fn deref(&self) -> &Self::Target { self.inner }
1278 }
1279
1280 impl<'a> TrustedClosingTransaction<'a> {
1281         /// The pre-built Bitcoin commitment transaction
1282         pub fn built_transaction(&self) -> &Transaction {
1283                 &self.inner.built
1284         }
1285
1286         /// Get the SIGHASH_ALL sighash value of the transaction.
1287         ///
1288         /// This can be used to verify a signature.
1289         pub fn get_sighash_all(&self, funding_redeemscript: &Script, channel_value_satoshis: u64) -> Message {
1290                 let sighash = &sighash::SighashCache::new(&self.inner.built).segwit_signature_hash(0, funding_redeemscript, channel_value_satoshis, EcdsaSighashType::All).unwrap()[..];
1291                 hash_to_message!(sighash)
1292         }
1293
1294         /// Sign a transaction, either because we are counter-signing the counterparty's transaction or
1295         /// because we are about to broadcast a holder transaction.
1296         pub fn sign<T: secp256k1::Signing>(&self, funding_key: &SecretKey, funding_redeemscript: &Script, channel_value_satoshis: u64, secp_ctx: &Secp256k1<T>) -> Signature {
1297                 let sighash = self.get_sighash_all(funding_redeemscript, channel_value_satoshis);
1298                 sign(secp_ctx, &sighash, funding_key)
1299         }
1300 }
1301
1302 /// This class tracks the per-transaction information needed to build a commitment transaction and will
1303 /// actually build it and sign.  It is used for holder transactions that we sign only when needed
1304 /// and for transactions we sign for the counterparty.
1305 ///
1306 /// This class can be used inside a signer implementation to generate a signature given the relevant
1307 /// secret key.
1308 #[derive(Clone)]
1309 pub struct CommitmentTransaction {
1310         commitment_number: u64,
1311         to_broadcaster_value_sat: u64,
1312         to_countersignatory_value_sat: u64,
1313         to_broadcaster_delay: Option<u16>, // Added in 0.0.117
1314         feerate_per_kw: u32,
1315         htlcs: Vec<HTLCOutputInCommitment>,
1316         // Note that on upgrades, some features of existing outputs may be missed.
1317         channel_type_features: ChannelTypeFeatures,
1318         // A cache of the parties' pubkeys required to construct the transaction, see doc for trust()
1319         keys: TxCreationKeys,
1320         // For access to the pre-built transaction, see doc for trust()
1321         built: BuiltCommitmentTransaction,
1322 }
1323
1324 impl Eq for CommitmentTransaction {}
1325 impl PartialEq for CommitmentTransaction {
1326         fn eq(&self, o: &Self) -> bool {
1327                 let eq = self.commitment_number == o.commitment_number &&
1328                         self.to_broadcaster_value_sat == o.to_broadcaster_value_sat &&
1329                         self.to_countersignatory_value_sat == o.to_countersignatory_value_sat &&
1330                         self.feerate_per_kw == o.feerate_per_kw &&
1331                         self.htlcs == o.htlcs &&
1332                         self.channel_type_features == o.channel_type_features &&
1333                         self.keys == o.keys;
1334                 if eq {
1335                         debug_assert_eq!(self.built.transaction, o.built.transaction);
1336                         debug_assert_eq!(self.built.txid, o.built.txid);
1337                 }
1338                 eq
1339         }
1340 }
1341
1342 impl Writeable for CommitmentTransaction {
1343         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
1344                 let legacy_deserialization_prevention_marker = legacy_deserialization_prevention_marker_for_channel_type_features(&self.channel_type_features);
1345                 write_tlv_fields!(writer, {
1346                         (0, self.commitment_number, required),
1347                         (1, self.to_broadcaster_delay, option),
1348                         (2, self.to_broadcaster_value_sat, required),
1349                         (4, self.to_countersignatory_value_sat, required),
1350                         (6, self.feerate_per_kw, required),
1351                         (8, self.keys, required),
1352                         (10, self.built, required),
1353                         (12, self.htlcs, required_vec),
1354                         (14, legacy_deserialization_prevention_marker, option),
1355                         (15, self.channel_type_features, required),
1356                 });
1357                 Ok(())
1358         }
1359 }
1360
1361 impl Readable for CommitmentTransaction {
1362         fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
1363                 _init_and_read_len_prefixed_tlv_fields!(reader, {
1364                         (0, commitment_number, required),
1365                         (1, to_broadcaster_delay, option),
1366                         (2, to_broadcaster_value_sat, required),
1367                         (4, to_countersignatory_value_sat, required),
1368                         (6, feerate_per_kw, required),
1369                         (8, keys, required),
1370                         (10, built, required),
1371                         (12, htlcs, required_vec),
1372                         (14, _legacy_deserialization_prevention_marker, option),
1373                         (15, channel_type_features, option),
1374                 });
1375
1376                 let mut additional_features = ChannelTypeFeatures::empty();
1377                 additional_features.set_anchors_nonzero_fee_htlc_tx_required();
1378                 chain::package::verify_channel_type_features(&channel_type_features, Some(&additional_features))?;
1379
1380                 Ok(Self {
1381                         commitment_number: commitment_number.0.unwrap(),
1382                         to_broadcaster_value_sat: to_broadcaster_value_sat.0.unwrap(),
1383                         to_countersignatory_value_sat: to_countersignatory_value_sat.0.unwrap(),
1384                         to_broadcaster_delay,
1385                         feerate_per_kw: feerate_per_kw.0.unwrap(),
1386                         keys: keys.0.unwrap(),
1387                         built: built.0.unwrap(),
1388                         htlcs,
1389                         channel_type_features: channel_type_features.unwrap_or(ChannelTypeFeatures::only_static_remote_key())
1390                 })
1391         }
1392 }
1393
1394 impl CommitmentTransaction {
1395         /// Construct an object of the class while assigning transaction output indices to HTLCs.
1396         ///
1397         /// Populates HTLCOutputInCommitment.transaction_output_index in htlcs_with_aux.
1398         ///
1399         /// The generic T allows the caller to match the HTLC output index with auxiliary data.
1400         /// This auxiliary data is not stored in this object.
1401         ///
1402         /// Only include HTLCs that are above the dust limit for the channel.
1403         ///
1404         /// This is not exported to bindings users due to the generic though we likely should expose a version without
1405         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 {
1406                 // Sort outputs and populate output indices while keeping track of the auxiliary data
1407                 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();
1408
1409                 let (obscured_commitment_transaction_number, txins) = Self::internal_build_inputs(commitment_number, channel_parameters);
1410                 let transaction = Self::make_transaction(obscured_commitment_transaction_number, txins, outputs);
1411                 let txid = transaction.txid();
1412                 CommitmentTransaction {
1413                         commitment_number,
1414                         to_broadcaster_value_sat,
1415                         to_countersignatory_value_sat,
1416                         to_broadcaster_delay: Some(channel_parameters.contest_delay()),
1417                         feerate_per_kw,
1418                         htlcs,
1419                         channel_type_features: channel_parameters.channel_type_features().clone(),
1420                         keys,
1421                         built: BuiltCommitmentTransaction {
1422                                 transaction,
1423                                 txid
1424                         },
1425                 }
1426         }
1427
1428         /// Use non-zero fee anchors
1429         ///
1430         /// This is not exported to bindings users due to move, and also not likely to be useful for binding users
1431         pub fn with_non_zero_fee_anchors(mut self) -> Self {
1432                 self.channel_type_features.set_anchors_nonzero_fee_htlc_tx_required();
1433                 self
1434         }
1435
1436         fn internal_rebuild_transaction(&self, keys: &TxCreationKeys, channel_parameters: &DirectedChannelTransactionParameters, broadcaster_funding_key: &PublicKey, countersignatory_funding_key: &PublicKey) -> Result<BuiltCommitmentTransaction, ()> {
1437                 let (obscured_commitment_transaction_number, txins) = Self::internal_build_inputs(self.commitment_number, channel_parameters);
1438
1439                 let mut htlcs_with_aux = self.htlcs.iter().map(|h| (h.clone(), ())).collect();
1440                 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)?;
1441
1442                 let transaction = Self::make_transaction(obscured_commitment_transaction_number, txins, outputs);
1443                 let txid = transaction.txid();
1444                 let built_transaction = BuiltCommitmentTransaction {
1445                         transaction,
1446                         txid
1447                 };
1448                 Ok(built_transaction)
1449         }
1450
1451         fn make_transaction(obscured_commitment_transaction_number: u64, txins: Vec<TxIn>, outputs: Vec<TxOut>) -> Transaction {
1452                 Transaction {
1453                         version: 2,
1454                         lock_time: PackedLockTime(((0x20 as u32) << 8 * 3) | ((obscured_commitment_transaction_number & 0xffffffu64) as u32)),
1455                         input: txins,
1456                         output: outputs,
1457                 }
1458         }
1459
1460         // This is used in two cases:
1461         // - initial sorting of outputs / HTLCs in the constructor, in which case T is auxiliary data the
1462         //   caller needs to have sorted together with the HTLCs so it can keep track of the output index
1463         // - building of a bitcoin transaction during a verify() call, in which case T is just ()
1464         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>), ()> {
1465                 let countersignatory_pubkeys = channel_parameters.countersignatory_pubkeys();
1466                 let contest_delay = channel_parameters.contest_delay();
1467
1468                 let mut txouts: Vec<(TxOut, Option<&mut HTLCOutputInCommitment>)> = Vec::new();
1469
1470                 if to_countersignatory_value_sat > 0 {
1471                         let script = if channel_parameters.channel_type_features().supports_anchors_zero_fee_htlc_tx() {
1472                             get_to_countersignatory_with_anchors_redeemscript(&countersignatory_pubkeys.payment_point).to_v0_p2wsh()
1473                         } else {
1474                             Payload::p2wpkh(&BitcoinPublicKey::new(countersignatory_pubkeys.payment_point)).unwrap().script_pubkey()
1475                         };
1476                         txouts.push((
1477                                 TxOut {
1478                                         script_pubkey: script.clone(),
1479                                         value: to_countersignatory_value_sat,
1480                                 },
1481                                 None,
1482                         ))
1483                 }
1484
1485                 if to_broadcaster_value_sat > 0 {
1486                         let redeem_script = get_revokeable_redeemscript(
1487                                 &keys.revocation_key,
1488                                 contest_delay,
1489                                 &keys.broadcaster_delayed_payment_key,
1490                         );
1491                         txouts.push((
1492                                 TxOut {
1493                                         script_pubkey: redeem_script.to_v0_p2wsh(),
1494                                         value: to_broadcaster_value_sat,
1495                                 },
1496                                 None,
1497                         ));
1498                 }
1499
1500                 if channel_parameters.channel_type_features().supports_anchors_zero_fee_htlc_tx() {
1501                         if to_broadcaster_value_sat > 0 || !htlcs_with_aux.is_empty() {
1502                                 let anchor_script = get_anchor_redeemscript(broadcaster_funding_key);
1503                                 txouts.push((
1504                                         TxOut {
1505                                                 script_pubkey: anchor_script.to_v0_p2wsh(),
1506                                                 value: ANCHOR_OUTPUT_VALUE_SATOSHI,
1507                                         },
1508                                         None,
1509                                 ));
1510                         }
1511
1512                         if to_countersignatory_value_sat > 0 || !htlcs_with_aux.is_empty() {
1513                                 let anchor_script = get_anchor_redeemscript(countersignatory_funding_key);
1514                                 txouts.push((
1515                                         TxOut {
1516                                                 script_pubkey: anchor_script.to_v0_p2wsh(),
1517                                                 value: ANCHOR_OUTPUT_VALUE_SATOSHI,
1518                                         },
1519                                         None,
1520                                 ));
1521                         }
1522                 }
1523
1524                 let mut htlcs = Vec::with_capacity(htlcs_with_aux.len());
1525                 for (htlc, _) in htlcs_with_aux {
1526                         let script = chan_utils::get_htlc_redeemscript(&htlc, &channel_parameters.channel_type_features(), &keys);
1527                         let txout = TxOut {
1528                                 script_pubkey: script.to_v0_p2wsh(),
1529                                 value: htlc.amount_msat / 1000,
1530                         };
1531                         txouts.push((txout, Some(htlc)));
1532                 }
1533
1534                 // Sort output in BIP-69 order (amount, scriptPubkey).  Tie-breaks based on HTLC
1535                 // CLTV expiration height.
1536                 sort_outputs(&mut txouts, |a, b| {
1537                         if let &Some(ref a_htlcout) = a {
1538                                 if let &Some(ref b_htlcout) = b {
1539                                         a_htlcout.cltv_expiry.cmp(&b_htlcout.cltv_expiry)
1540                                                 // Note that due to hash collisions, we have to have a fallback comparison
1541                                                 // here for fuzzing mode (otherwise at least chanmon_fail_consistency
1542                                                 // may fail)!
1543                                                 .then(a_htlcout.payment_hash.0.cmp(&b_htlcout.payment_hash.0))
1544                                 // For non-HTLC outputs, if they're copying our SPK we don't really care if we
1545                                 // close the channel due to mismatches - they're doing something dumb:
1546                                 } else { cmp::Ordering::Equal }
1547                         } else { cmp::Ordering::Equal }
1548                 });
1549
1550                 let mut outputs = Vec::with_capacity(txouts.len());
1551                 for (idx, out) in txouts.drain(..).enumerate() {
1552                         if let Some(htlc) = out.1 {
1553                                 htlc.transaction_output_index = Some(idx as u32);
1554                                 htlcs.push(htlc.clone());
1555                         }
1556                         outputs.push(out.0);
1557                 }
1558                 Ok((outputs, htlcs))
1559         }
1560
1561         fn internal_build_inputs(commitment_number: u64, channel_parameters: &DirectedChannelTransactionParameters) -> (u64, Vec<TxIn>) {
1562                 let broadcaster_pubkeys = channel_parameters.broadcaster_pubkeys();
1563                 let countersignatory_pubkeys = channel_parameters.countersignatory_pubkeys();
1564                 let commitment_transaction_number_obscure_factor = get_commitment_transaction_number_obscure_factor(
1565                         &broadcaster_pubkeys.payment_point,
1566                         &countersignatory_pubkeys.payment_point,
1567                         channel_parameters.is_outbound(),
1568                 );
1569
1570                 let obscured_commitment_transaction_number =
1571                         commitment_transaction_number_obscure_factor ^ (INITIAL_COMMITMENT_NUMBER - commitment_number);
1572
1573                 let txins = {
1574                         let mut ins: Vec<TxIn> = Vec::new();
1575                         ins.push(TxIn {
1576                                 previous_output: channel_parameters.funding_outpoint(),
1577                                 script_sig: Script::new(),
1578                                 sequence: Sequence(((0x80 as u32) << 8 * 3)
1579                                         | ((obscured_commitment_transaction_number >> 3 * 8) as u32)),
1580                                 witness: Witness::new(),
1581                         });
1582                         ins
1583                 };
1584                 (obscured_commitment_transaction_number, txins)
1585         }
1586
1587         /// The backwards-counting commitment number
1588         pub fn commitment_number(&self) -> u64 {
1589                 self.commitment_number
1590         }
1591
1592         /// The value to be sent to the broadcaster
1593         pub fn to_broadcaster_value_sat(&self) -> u64 {
1594                 self.to_broadcaster_value_sat
1595         }
1596
1597         /// The value to be sent to the counterparty
1598         pub fn to_countersignatory_value_sat(&self) -> u64 {
1599                 self.to_countersignatory_value_sat
1600         }
1601
1602         /// The feerate paid per 1000-weight-unit in this commitment transaction.
1603         pub fn feerate_per_kw(&self) -> u32 {
1604                 self.feerate_per_kw
1605         }
1606
1607         /// The non-dust HTLCs (direction, amt, height expiration, hash, transaction output index)
1608         /// which were included in this commitment transaction in output order.
1609         /// The transaction index is always populated.
1610         ///
1611         /// This is not exported to bindings users as we cannot currently convert Vec references to/from C, though we should
1612         /// expose a less effecient version which creates a Vec of references in the future.
1613         pub fn htlcs(&self) -> &Vec<HTLCOutputInCommitment> {
1614                 &self.htlcs
1615         }
1616
1617         /// Trust our pre-built transaction and derived transaction creation public keys.
1618         ///
1619         /// Applies a wrapper which allows access to these fields.
1620         ///
1621         /// This should only be used if you fully trust the builder of this object.  It should not
1622         /// be used by an external signer - instead use the verify function.
1623         pub fn trust(&self) -> TrustedCommitmentTransaction {
1624                 TrustedCommitmentTransaction { inner: self }
1625         }
1626
1627         /// Verify our pre-built transaction and derived transaction creation public keys.
1628         ///
1629         /// Applies a wrapper which allows access to these fields.
1630         ///
1631         /// An external validating signer must call this method before signing
1632         /// or using the built transaction.
1633         pub fn verify<T: secp256k1::Signing + secp256k1::Verification>(&self, channel_parameters: &DirectedChannelTransactionParameters, broadcaster_keys: &ChannelPublicKeys, countersignatory_keys: &ChannelPublicKeys, secp_ctx: &Secp256k1<T>) -> Result<TrustedCommitmentTransaction, ()> {
1634                 // This is the only field of the key cache that we trust
1635                 let per_commitment_point = self.keys.per_commitment_point;
1636                 let keys = TxCreationKeys::from_channel_static_keys(&per_commitment_point, broadcaster_keys, countersignatory_keys, secp_ctx);
1637                 if keys != self.keys {
1638                         return Err(());
1639                 }
1640                 let tx = self.internal_rebuild_transaction(&keys, channel_parameters, &broadcaster_keys.funding_pubkey, &countersignatory_keys.funding_pubkey)?;
1641                 if self.built.transaction != tx.transaction || self.built.txid != tx.txid {
1642                         return Err(());
1643                 }
1644                 Ok(TrustedCommitmentTransaction { inner: self })
1645         }
1646 }
1647
1648 /// A wrapper on CommitmentTransaction indicating that the derived fields (the built bitcoin
1649 /// transaction and the transaction creation keys) are trusted.
1650 ///
1651 /// See trust() and verify() functions on CommitmentTransaction.
1652 ///
1653 /// This structure implements Deref.
1654 pub struct TrustedCommitmentTransaction<'a> {
1655         inner: &'a CommitmentTransaction,
1656 }
1657
1658 impl<'a> Deref for TrustedCommitmentTransaction<'a> {
1659         type Target = CommitmentTransaction;
1660
1661         fn deref(&self) -> &Self::Target { self.inner }
1662 }
1663
1664 impl<'a> TrustedCommitmentTransaction<'a> {
1665         /// The transaction ID of the built Bitcoin transaction
1666         pub fn txid(&self) -> Txid {
1667                 self.inner.built.txid
1668         }
1669
1670         /// The pre-built Bitcoin commitment transaction
1671         pub fn built_transaction(&self) -> &BuiltCommitmentTransaction {
1672                 &self.inner.built
1673         }
1674
1675         /// The pre-calculated transaction creation public keys.
1676         pub fn keys(&self) -> &TxCreationKeys {
1677                 &self.inner.keys
1678         }
1679
1680         /// Should anchors be used.
1681         pub fn channel_type_features(&self) -> &ChannelTypeFeatures {
1682                 &self.inner.channel_type_features
1683         }
1684
1685         /// Get a signature for each HTLC which was included in the commitment transaction (ie for
1686         /// which HTLCOutputInCommitment::transaction_output_index.is_some()).
1687         ///
1688         /// The returned Vec has one entry for each HTLC, and in the same order.
1689         ///
1690         /// This function is only valid in the holder commitment context, it always uses EcdsaSighashType::All.
1691         pub fn get_htlc_sigs<T: secp256k1::Signing, ES: Deref>(
1692                 &self, htlc_base_key: &SecretKey, channel_parameters: &DirectedChannelTransactionParameters,
1693                 entropy_source: &ES, secp_ctx: &Secp256k1<T>,
1694         ) -> Result<Vec<Signature>, ()> where ES::Target: EntropySource {
1695                 let inner = self.inner;
1696                 let keys = &inner.keys;
1697                 let txid = inner.built.txid;
1698                 let mut ret = Vec::with_capacity(inner.htlcs.len());
1699                 let holder_htlc_key = derive_private_key(secp_ctx, &inner.keys.per_commitment_point, htlc_base_key);
1700
1701                 for this_htlc in inner.htlcs.iter() {
1702                         assert!(this_htlc.transaction_output_index.is_some());
1703                         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);
1704
1705                         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);
1706
1707                         let sighash = hash_to_message!(&sighash::SighashCache::new(&htlc_tx).segwit_signature_hash(0, &htlc_redeemscript, this_htlc.amount_msat / 1000, EcdsaSighashType::All).unwrap()[..]);
1708                         ret.push(sign_with_aux_rand(secp_ctx, &sighash, &holder_htlc_key, entropy_source));
1709                 }
1710                 Ok(ret)
1711         }
1712
1713         /// Gets a signed HTLC transaction given a preimage (for !htlc.offered) and the holder HTLC transaction signature.
1714         pub(crate) fn get_signed_htlc_tx(&self, channel_parameters: &DirectedChannelTransactionParameters, htlc_index: usize, counterparty_signature: &Signature, signature: &Signature, preimage: &Option<PaymentPreimage>) -> Transaction {
1715                 let inner = self.inner;
1716                 let keys = &inner.keys;
1717                 let txid = inner.built.txid;
1718                 let this_htlc = &inner.htlcs[htlc_index];
1719                 assert!(this_htlc.transaction_output_index.is_some());
1720                 // if we don't have preimage for an HTLC-Success, we can't generate an HTLC transaction.
1721                 if !this_htlc.offered && preimage.is_none() { unreachable!(); }
1722                 // Further, we should never be provided the preimage for an HTLC-Timeout transaction.
1723                 if  this_htlc.offered && preimage.is_some() { unreachable!(); }
1724
1725                 let mut 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);
1726
1727                 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);
1728
1729                 htlc_tx.input[0].witness = chan_utils::build_htlc_input_witness(
1730                         signature, counterparty_signature, preimage, &htlc_redeemscript, &self.channel_type_features,
1731                 );
1732                 htlc_tx
1733         }
1734
1735         /// Returns the index of the revokeable output, i.e. the `to_local` output sending funds to
1736         /// the broadcaster, in the built transaction, if any exists.
1737         ///
1738         /// There are two cases where this may return `None`:
1739         /// - The balance of the revokeable output is below the dust limit (only found on commitments
1740         /// early in the channel's lifetime, i.e. before the channel reserve is met).
1741         /// - This commitment was created before LDK 0.0.117. In this case, the
1742         /// commitment transaction previously didn't contain enough information to locate the
1743         /// revokeable output.
1744         pub fn revokeable_output_index(&self) -> Option<usize> {
1745                 let revokeable_redeemscript = get_revokeable_redeemscript(
1746                         &self.keys.revocation_key,
1747                         self.to_broadcaster_delay?,
1748                         &self.keys.broadcaster_delayed_payment_key,
1749                 );
1750                 let revokeable_p2wsh = revokeable_redeemscript.to_v0_p2wsh();
1751                 let outputs = &self.inner.built.transaction.output;
1752                 outputs.iter().enumerate()
1753                         .find(|(_, out)| out.script_pubkey == revokeable_p2wsh)
1754                         .map(|(idx, _)| idx)
1755         }
1756
1757         /// Helper method to build an unsigned justice transaction spending the revokeable
1758         /// `to_local` output to a destination script. Fee estimation accounts for the expected
1759         /// revocation witness data that will be added when signed.
1760         ///
1761         /// This method will error if the given fee rate results in a fee greater than the value
1762         /// of the output being spent, or if there exists no revokeable `to_local` output on this
1763         /// commitment transaction. See [`Self::revokeable_output_index`] for more details.
1764         ///
1765         /// The built transaction will allow fee bumping with RBF, and this method takes
1766         /// `feerate_per_kw` as an input such that multiple copies of a justice transaction at different
1767         /// fee rates may be built.
1768         pub fn build_to_local_justice_tx(&self, feerate_per_kw: u64, destination_script: Script)
1769         -> Result<Transaction, ()> {
1770                 let output_idx = self.revokeable_output_index().ok_or(())?;
1771                 let input = vec![TxIn {
1772                         previous_output: OutPoint {
1773                                 txid: self.trust().txid(),
1774                                 vout: output_idx as u32,
1775                         },
1776                         script_sig: Script::new(),
1777                         sequence: Sequence::ENABLE_RBF_NO_LOCKTIME,
1778                         witness: Witness::new(),
1779                 }];
1780                 let value = self.inner.built.transaction.output[output_idx].value;
1781                 let output = vec![TxOut {
1782                         script_pubkey: destination_script,
1783                         value,
1784                 }];
1785                 let mut justice_tx = Transaction {
1786                         version: 2,
1787                         lock_time: PackedLockTime::ZERO,
1788                         input,
1789                         output,
1790                 };
1791                 let weight = justice_tx.weight() as u64 + WEIGHT_REVOKED_OUTPUT;
1792                 let fee = fee_for_weight(feerate_per_kw as u32, weight);
1793                 justice_tx.output[0].value = value.checked_sub(fee).ok_or(())?;
1794                 Ok(justice_tx)
1795         }
1796
1797 }
1798
1799 /// Commitment transaction numbers which appear in the transactions themselves are XOR'd with a
1800 /// shared secret first. This prevents on-chain observers from discovering how many commitment
1801 /// transactions occurred in a channel before it was closed.
1802 ///
1803 /// This function gets the shared secret from relevant channel public keys and can be used to
1804 /// "decrypt" the commitment transaction number given a commitment transaction on-chain.
1805 pub fn get_commitment_transaction_number_obscure_factor(
1806         broadcaster_payment_basepoint: &PublicKey,
1807         countersignatory_payment_basepoint: &PublicKey,
1808         outbound_from_broadcaster: bool,
1809 ) -> u64 {
1810         let mut sha = Sha256::engine();
1811
1812         if outbound_from_broadcaster {
1813                 sha.input(&broadcaster_payment_basepoint.serialize());
1814                 sha.input(&countersignatory_payment_basepoint.serialize());
1815         } else {
1816                 sha.input(&countersignatory_payment_basepoint.serialize());
1817                 sha.input(&broadcaster_payment_basepoint.serialize());
1818         }
1819         let res = Sha256::from_engine(sha).into_inner();
1820
1821         ((res[26] as u64) << 5 * 8)
1822                 | ((res[27] as u64) << 4 * 8)
1823                 | ((res[28] as u64) << 3 * 8)
1824                 | ((res[29] as u64) << 2 * 8)
1825                 | ((res[30] as u64) << 1 * 8)
1826                 | ((res[31] as u64) << 0 * 8)
1827 }
1828
1829 #[cfg(test)]
1830 mod tests {
1831         use super::{CounterpartyCommitmentSecrets, ChannelPublicKeys};
1832         use crate::{hex, chain};
1833         use crate::prelude::*;
1834         use crate::ln::chan_utils::{get_htlc_redeemscript, get_to_countersignatory_with_anchors_redeemscript, CommitmentTransaction, TxCreationKeys, ChannelTransactionParameters, CounterpartyChannelTransactionParameters, HTLCOutputInCommitment};
1835         use bitcoin::secp256k1::{PublicKey, SecretKey, Secp256k1};
1836         use crate::util::test_utils;
1837         use crate::sign::{ChannelSigner, SignerProvider};
1838         use bitcoin::{Network, Txid, Script};
1839         use bitcoin::hashes::Hash;
1840         use crate::ln::PaymentHash;
1841         use bitcoin::hashes::hex::ToHex;
1842         use bitcoin::util::address::Payload;
1843         use bitcoin::PublicKey as BitcoinPublicKey;
1844         use crate::ln::features::ChannelTypeFeatures;
1845
1846         struct TestCommitmentTxBuilder {
1847                 commitment_number: u64,
1848                 holder_funding_pubkey: PublicKey,
1849                 counterparty_funding_pubkey: PublicKey,
1850                 keys: TxCreationKeys,
1851                 feerate_per_kw: u32,
1852                 htlcs_with_aux: Vec<(HTLCOutputInCommitment, ())>,
1853                 channel_parameters: ChannelTransactionParameters,
1854                 counterparty_pubkeys: ChannelPublicKeys,
1855         }
1856
1857         impl TestCommitmentTxBuilder {
1858                 fn new() -> Self {
1859                         let secp_ctx = Secp256k1::new();
1860                         let seed = [42; 32];
1861                         let network = Network::Testnet;
1862                         let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
1863                         let signer = keys_provider.derive_channel_signer(3000, keys_provider.generate_channel_keys_id(false, 1_000_000, 0));
1864                         let counterparty_signer = keys_provider.derive_channel_signer(3000, keys_provider.generate_channel_keys_id(true, 1_000_000, 1));
1865                         let delayed_payment_base = &signer.pubkeys().delayed_payment_basepoint;
1866                         let per_commitment_secret = SecretKey::from_slice(&hex::decode("1f1e1d1c1b1a191817161514131211100f0e0d0c0b0a09080706050403020100").unwrap()[..]).unwrap();
1867                         let per_commitment_point = PublicKey::from_secret_key(&secp_ctx, &per_commitment_secret);
1868                         let htlc_basepoint = &signer.pubkeys().htlc_basepoint;
1869                         let holder_pubkeys = signer.pubkeys();
1870                         let counterparty_pubkeys = counterparty_signer.pubkeys().clone();
1871                         let keys = TxCreationKeys::derive_new(&secp_ctx, &per_commitment_point, delayed_payment_base, htlc_basepoint, &counterparty_pubkeys.revocation_basepoint, &counterparty_pubkeys.htlc_basepoint);
1872                         let channel_parameters = ChannelTransactionParameters {
1873                                 holder_pubkeys: holder_pubkeys.clone(),
1874                                 holder_selected_contest_delay: 0,
1875                                 is_outbound_from_holder: false,
1876                                 counterparty_parameters: Some(CounterpartyChannelTransactionParameters { pubkeys: counterparty_pubkeys.clone(), selected_contest_delay: 0 }),
1877                                 funding_outpoint: Some(chain::transaction::OutPoint { txid: Txid::all_zeros(), index: 0 }),
1878                                 channel_type_features: ChannelTypeFeatures::only_static_remote_key(),
1879                         };
1880                         let htlcs_with_aux = Vec::new();
1881
1882                         Self {
1883                                 commitment_number: 0,
1884                                 holder_funding_pubkey: holder_pubkeys.funding_pubkey,
1885                                 counterparty_funding_pubkey: counterparty_pubkeys.funding_pubkey,
1886                                 keys,
1887                                 feerate_per_kw: 1,
1888                                 htlcs_with_aux,
1889                                 channel_parameters,
1890                                 counterparty_pubkeys,
1891                         }
1892                 }
1893
1894                 fn build(&mut self, to_broadcaster_sats: u64, to_countersignatory_sats: u64) -> CommitmentTransaction {
1895                         CommitmentTransaction::new_with_auxiliary_htlc_data(
1896                                 self.commitment_number, to_broadcaster_sats, to_countersignatory_sats,
1897                                 self.holder_funding_pubkey.clone(),
1898                                 self.counterparty_funding_pubkey.clone(),
1899                                 self.keys.clone(), self.feerate_per_kw,
1900                                 &mut self.htlcs_with_aux, &self.channel_parameters.as_holder_broadcastable()
1901                         )
1902                 }
1903         }
1904
1905         #[test]
1906         fn test_anchors() {
1907                 let mut builder = TestCommitmentTxBuilder::new();
1908
1909                 // Generate broadcaster and counterparty outputs
1910                 let tx = builder.build(1000, 2000);
1911                 assert_eq!(tx.built.transaction.output.len(), 2);
1912                 assert_eq!(tx.built.transaction.output[1].script_pubkey, Payload::p2wpkh(&BitcoinPublicKey::new(builder.counterparty_pubkeys.payment_point)).unwrap().script_pubkey());
1913
1914                 // Generate broadcaster and counterparty outputs as well as two anchors
1915                 builder.channel_parameters.channel_type_features = ChannelTypeFeatures::anchors_zero_htlc_fee_and_dependencies();
1916                 let tx = builder.build(1000, 2000);
1917                 assert_eq!(tx.built.transaction.output.len(), 4);
1918                 assert_eq!(tx.built.transaction.output[3].script_pubkey, get_to_countersignatory_with_anchors_redeemscript(&builder.counterparty_pubkeys.payment_point).to_v0_p2wsh());
1919
1920                 // Generate broadcaster output and anchor
1921                 let tx = builder.build(3000, 0);
1922                 assert_eq!(tx.built.transaction.output.len(), 2);
1923
1924                 // Generate counterparty output and anchor
1925                 let tx = builder.build(0, 3000);
1926                 assert_eq!(tx.built.transaction.output.len(), 2);
1927
1928                 let received_htlc = HTLCOutputInCommitment {
1929                         offered: false,
1930                         amount_msat: 400000,
1931                         cltv_expiry: 100,
1932                         payment_hash: PaymentHash([42; 32]),
1933                         transaction_output_index: None,
1934                 };
1935
1936                 let offered_htlc = HTLCOutputInCommitment {
1937                         offered: true,
1938                         amount_msat: 600000,
1939                         cltv_expiry: 100,
1940                         payment_hash: PaymentHash([43; 32]),
1941                         transaction_output_index: None,
1942                 };
1943
1944                 // Generate broadcaster output and received and offered HTLC outputs,  w/o anchors
1945                 builder.channel_parameters.channel_type_features = ChannelTypeFeatures::only_static_remote_key();
1946                 builder.htlcs_with_aux = vec![(received_htlc.clone(), ()), (offered_htlc.clone(), ())];
1947                 let tx = builder.build(3000, 0);
1948                 let keys = &builder.keys.clone();
1949                 assert_eq!(tx.built.transaction.output.len(), 3);
1950                 assert_eq!(tx.built.transaction.output[0].script_pubkey, get_htlc_redeemscript(&received_htlc, &ChannelTypeFeatures::only_static_remote_key(), &keys).to_v0_p2wsh());
1951                 assert_eq!(tx.built.transaction.output[1].script_pubkey, get_htlc_redeemscript(&offered_htlc, &ChannelTypeFeatures::only_static_remote_key(), &keys).to_v0_p2wsh());
1952                 assert_eq!(get_htlc_redeemscript(&received_htlc, &ChannelTypeFeatures::only_static_remote_key(), &keys).to_v0_p2wsh().to_hex(),
1953                                    "0020e43a7c068553003fe68fcae424fb7b28ec5ce48cd8b6744b3945631389bad2fb");
1954                 assert_eq!(get_htlc_redeemscript(&offered_htlc, &ChannelTypeFeatures::only_static_remote_key(), &keys).to_v0_p2wsh().to_hex(),
1955                                    "0020215d61bba56b19e9eadb6107f5a85d7f99c40f65992443f69229c290165bc00d");
1956
1957                 // Generate broadcaster output and received and offered HTLC outputs,  with anchors
1958                 builder.channel_parameters.channel_type_features = ChannelTypeFeatures::anchors_zero_htlc_fee_and_dependencies();
1959                 builder.htlcs_with_aux = vec![(received_htlc.clone(), ()), (offered_htlc.clone(), ())];
1960                 let tx = builder.build(3000, 0);
1961                 assert_eq!(tx.built.transaction.output.len(), 5);
1962                 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());
1963                 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());
1964                 assert_eq!(get_htlc_redeemscript(&received_htlc, &ChannelTypeFeatures::anchors_zero_htlc_fee_and_dependencies(), &keys).to_v0_p2wsh().to_hex(),
1965                                    "0020b70d0649c72b38756885c7a30908d912a7898dd5d79457a7280b8e9a20f3f2bc");
1966                 assert_eq!(get_htlc_redeemscript(&offered_htlc, &ChannelTypeFeatures::anchors_zero_htlc_fee_and_dependencies(), &keys).to_v0_p2wsh().to_hex(),
1967                                    "002087a3faeb1950a469c0e2db4a79b093a41b9526e5a6fc6ef5cb949bde3be379c7");
1968         }
1969
1970         #[test]
1971         fn test_finding_revokeable_output_index() {
1972                 let mut builder = TestCommitmentTxBuilder::new();
1973
1974                 // Revokeable output present
1975                 let tx = builder.build(1000, 2000);
1976                 assert_eq!(tx.built.transaction.output.len(), 2);
1977                 assert_eq!(tx.trust().revokeable_output_index(), Some(0));
1978
1979                 // Revokeable output present (but to_broadcaster_delay missing)
1980                 let tx = CommitmentTransaction { to_broadcaster_delay: None, ..tx };
1981                 assert_eq!(tx.built.transaction.output.len(), 2);
1982                 assert_eq!(tx.trust().revokeable_output_index(), None);
1983
1984                 // Revokeable output not present (our balance is dust)
1985                 let tx = builder.build(0, 2000);
1986                 assert_eq!(tx.built.transaction.output.len(), 1);
1987                 assert_eq!(tx.trust().revokeable_output_index(), None);
1988         }
1989
1990         #[test]
1991         fn test_building_to_local_justice_tx() {
1992                 let mut builder = TestCommitmentTxBuilder::new();
1993
1994                 // Revokeable output not present (our balance is dust)
1995                 let tx = builder.build(0, 2000);
1996                 assert_eq!(tx.built.transaction.output.len(), 1);
1997                 assert!(tx.trust().build_to_local_justice_tx(253, Script::new()).is_err());
1998
1999                 // Revokeable output present
2000                 let tx = builder.build(1000, 2000);
2001                 assert_eq!(tx.built.transaction.output.len(), 2);
2002
2003                 // Too high feerate
2004                 assert!(tx.trust().build_to_local_justice_tx(100_000, Script::new()).is_err());
2005
2006                 // Generate a random public key for destination script
2007                 let secret_key = SecretKey::from_slice(
2008                         &hex::decode("1f1e1d1c1b1a191817161514131211100f0e0d0c0b0a09080706050403020100")
2009                         .unwrap()[..]).unwrap();
2010                 let pubkey_hash = BitcoinPublicKey::new(
2011                         PublicKey::from_secret_key(&Secp256k1::new(), &secret_key)).wpubkey_hash().unwrap();
2012                 let destination_script = Script::new_v0_p2wpkh(&pubkey_hash);
2013
2014                 let justice_tx = tx.trust().build_to_local_justice_tx(253, destination_script.clone()).unwrap();
2015                 assert_eq!(justice_tx.input.len(), 1);
2016                 assert_eq!(justice_tx.input[0].previous_output.txid, tx.built.transaction.txid());
2017                 assert_eq!(justice_tx.input[0].previous_output.vout, tx.trust().revokeable_output_index().unwrap() as u32);
2018                 assert!(justice_tx.input[0].sequence.is_rbf());
2019
2020                 assert_eq!(justice_tx.output.len(), 1);
2021                 assert!(justice_tx.output[0].value < 1000);
2022                 assert_eq!(justice_tx.output[0].script_pubkey, destination_script);
2023         }
2024
2025         #[test]
2026         fn test_per_commitment_storage() {
2027                 // Test vectors from BOLT 3:
2028                 let mut secrets: Vec<[u8; 32]> = Vec::new();
2029                 let mut monitor;
2030
2031                 macro_rules! test_secrets {
2032                         () => {
2033                                 let mut idx = 281474976710655;
2034                                 for secret in secrets.iter() {
2035                                         assert_eq!(monitor.get_secret(idx).unwrap(), *secret);
2036                                         idx -= 1;
2037                                 }
2038                                 assert_eq!(monitor.get_min_seen_secret(), idx + 1);
2039                                 assert!(monitor.get_secret(idx).is_none());
2040                         };
2041                 }
2042
2043                 {
2044                         // insert_secret correct sequence
2045                         monitor = CounterpartyCommitmentSecrets::new();
2046                         secrets.clear();
2047
2048                         secrets.push([0; 32]);
2049                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2050                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2051                         test_secrets!();
2052
2053                         secrets.push([0; 32]);
2054                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2055                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2056                         test_secrets!();
2057
2058                         secrets.push([0; 32]);
2059                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2060                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2061                         test_secrets!();
2062
2063                         secrets.push([0; 32]);
2064                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2065                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
2066                         test_secrets!();
2067
2068                         secrets.push([0; 32]);
2069                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
2070                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
2071                         test_secrets!();
2072
2073                         secrets.push([0; 32]);
2074                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
2075                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
2076                         test_secrets!();
2077
2078                         secrets.push([0; 32]);
2079                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
2080                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
2081                         test_secrets!();
2082
2083                         secrets.push([0; 32]);
2084                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
2085                         monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap();
2086                         test_secrets!();
2087                 }
2088
2089                 {
2090                         // insert_secret #1 incorrect
2091                         monitor = CounterpartyCommitmentSecrets::new();
2092                         secrets.clear();
2093
2094                         secrets.push([0; 32]);
2095                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
2096                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2097                         test_secrets!();
2098
2099                         secrets.push([0; 32]);
2100                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2101                         assert!(monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).is_err());
2102                 }
2103
2104                 {
2105                         // insert_secret #2 incorrect (#1 derived from incorrect)
2106                         monitor = CounterpartyCommitmentSecrets::new();
2107                         secrets.clear();
2108
2109                         secrets.push([0; 32]);
2110                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
2111                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2112                         test_secrets!();
2113
2114                         secrets.push([0; 32]);
2115                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("dddc3a8d14fddf2b68fa8c7fbad2748274937479dd0f8930d5ebb4ab6bd866a3").unwrap());
2116                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2117                         test_secrets!();
2118
2119                         secrets.push([0; 32]);
2120                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2121                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2122                         test_secrets!();
2123
2124                         secrets.push([0; 32]);
2125                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2126                         assert!(monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).is_err());
2127                 }
2128
2129                 {
2130                         // insert_secret #3 incorrect
2131                         monitor = CounterpartyCommitmentSecrets::new();
2132                         secrets.clear();
2133
2134                         secrets.push([0; 32]);
2135                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2136                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2137                         test_secrets!();
2138
2139                         secrets.push([0; 32]);
2140                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2141                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2142                         test_secrets!();
2143
2144                         secrets.push([0; 32]);
2145                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c51a18b13e8527e579ec56365482c62f180b7d5760b46e9477dae59e87ed423a").unwrap());
2146                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2147                         test_secrets!();
2148
2149                         secrets.push([0; 32]);
2150                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2151                         assert!(monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).is_err());
2152                 }
2153
2154                 {
2155                         // insert_secret #4 incorrect (1,2,3 derived from incorrect)
2156                         monitor = CounterpartyCommitmentSecrets::new();
2157                         secrets.clear();
2158
2159                         secrets.push([0; 32]);
2160                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
2161                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2162                         test_secrets!();
2163
2164                         secrets.push([0; 32]);
2165                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("dddc3a8d14fddf2b68fa8c7fbad2748274937479dd0f8930d5ebb4ab6bd866a3").unwrap());
2166                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2167                         test_secrets!();
2168
2169                         secrets.push([0; 32]);
2170                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c51a18b13e8527e579ec56365482c62f180b7d5760b46e9477dae59e87ed423a").unwrap());
2171                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2172                         test_secrets!();
2173
2174                         secrets.push([0; 32]);
2175                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("ba65d7b0ef55a3ba300d4e87af29868f394f8f138d78a7011669c79b37b936f4").unwrap());
2176                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
2177                         test_secrets!();
2178
2179                         secrets.push([0; 32]);
2180                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
2181                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
2182                         test_secrets!();
2183
2184                         secrets.push([0; 32]);
2185                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
2186                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
2187                         test_secrets!();
2188
2189                         secrets.push([0; 32]);
2190                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
2191                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
2192                         test_secrets!();
2193
2194                         secrets.push([0; 32]);
2195                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
2196                         assert!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).is_err());
2197                 }
2198
2199                 {
2200                         // insert_secret #5 incorrect
2201                         monitor = CounterpartyCommitmentSecrets::new();
2202                         secrets.clear();
2203
2204                         secrets.push([0; 32]);
2205                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2206                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2207                         test_secrets!();
2208
2209                         secrets.push([0; 32]);
2210                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2211                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2212                         test_secrets!();
2213
2214                         secrets.push([0; 32]);
2215                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2216                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2217                         test_secrets!();
2218
2219                         secrets.push([0; 32]);
2220                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2221                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
2222                         test_secrets!();
2223
2224                         secrets.push([0; 32]);
2225                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("631373ad5f9ef654bb3dade742d09504c567edd24320d2fcd68e3cc47e2ff6a6").unwrap());
2226                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
2227                         test_secrets!();
2228
2229                         secrets.push([0; 32]);
2230                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
2231                         assert!(monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).is_err());
2232                 }
2233
2234                 {
2235                         // insert_secret #6 incorrect (5 derived from incorrect)
2236                         monitor = CounterpartyCommitmentSecrets::new();
2237                         secrets.clear();
2238
2239                         secrets.push([0; 32]);
2240                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2241                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2242                         test_secrets!();
2243
2244                         secrets.push([0; 32]);
2245                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2246                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2247                         test_secrets!();
2248
2249                         secrets.push([0; 32]);
2250                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2251                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2252                         test_secrets!();
2253
2254                         secrets.push([0; 32]);
2255                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2256                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
2257                         test_secrets!();
2258
2259                         secrets.push([0; 32]);
2260                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("631373ad5f9ef654bb3dade742d09504c567edd24320d2fcd68e3cc47e2ff6a6").unwrap());
2261                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
2262                         test_secrets!();
2263
2264                         secrets.push([0; 32]);
2265                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("b7e76a83668bde38b373970155c868a653304308f9896692f904a23731224bb1").unwrap());
2266                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
2267                         test_secrets!();
2268
2269                         secrets.push([0; 32]);
2270                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
2271                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
2272                         test_secrets!();
2273
2274                         secrets.push([0; 32]);
2275                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
2276                         assert!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).is_err());
2277                 }
2278
2279                 {
2280                         // insert_secret #7 incorrect
2281                         monitor = CounterpartyCommitmentSecrets::new();
2282                         secrets.clear();
2283
2284                         secrets.push([0; 32]);
2285                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2286                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2287                         test_secrets!();
2288
2289                         secrets.push([0; 32]);
2290                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2291                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2292                         test_secrets!();
2293
2294                         secrets.push([0; 32]);
2295                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2296                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2297                         test_secrets!();
2298
2299                         secrets.push([0; 32]);
2300                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2301                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
2302                         test_secrets!();
2303
2304                         secrets.push([0; 32]);
2305                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
2306                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
2307                         test_secrets!();
2308
2309                         secrets.push([0; 32]);
2310                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
2311                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
2312                         test_secrets!();
2313
2314                         secrets.push([0; 32]);
2315                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("e7971de736e01da8ed58b94c2fc216cb1dca9e326f3a96e7194fe8ea8af6c0a3").unwrap());
2316                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
2317                         test_secrets!();
2318
2319                         secrets.push([0; 32]);
2320                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
2321                         assert!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).is_err());
2322                 }
2323
2324                 {
2325                         // insert_secret #8 incorrect
2326                         monitor = CounterpartyCommitmentSecrets::new();
2327                         secrets.clear();
2328
2329                         secrets.push([0; 32]);
2330                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2331                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2332                         test_secrets!();
2333
2334                         secrets.push([0; 32]);
2335                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2336                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2337                         test_secrets!();
2338
2339                         secrets.push([0; 32]);
2340                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2341                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2342                         test_secrets!();
2343
2344                         secrets.push([0; 32]);
2345                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2346                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
2347                         test_secrets!();
2348
2349                         secrets.push([0; 32]);
2350                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
2351                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
2352                         test_secrets!();
2353
2354                         secrets.push([0; 32]);
2355                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
2356                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
2357                         test_secrets!();
2358
2359                         secrets.push([0; 32]);
2360                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
2361                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
2362                         test_secrets!();
2363
2364                         secrets.push([0; 32]);
2365                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a7efbc61aac46d34f77778bac22c8a20c6a46ca460addc49009bda875ec88fa4").unwrap());
2366                         assert!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).is_err());
2367                 }
2368         }
2369 }