_ Git - rust-lightning/blob - 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 chain::keysinterface::Sign message signing by hand.
  12
  13 use bitcoin::blockdata::script::{Script,Builder};
  14 use bitcoin::blockdata::opcodes;
  15 use bitcoin::blockdata::transaction::{TxIn,TxOut,OutPoint,Transaction, SigHashType};
  16 use bitcoin::util::bip143;
  17
  18 use bitcoin::hashes::{Hash, HashEngine};
  19 use bitcoin::hashes::sha256::Hash as Sha256;
  20 use bitcoin::hashes::ripemd160::Hash as Ripemd160;
  21 use bitcoin::hash_types::{Txid, PubkeyHash};
  22
  23 use ln::{PaymentHash, PaymentPreimage};
  24 use ln::msgs::DecodeError;
  25 use util::ser::{Readable, Writeable, Writer};
  26 use util::byte_utils;
  27
  28 use bitcoin::hash_types::WPubkeyHash;
  29 use bitcoin::secp256k1::key::{SecretKey, PublicKey};
  30 use bitcoin::secp256k1::{Secp256k1, Signature, Message};
  31 use bitcoin::secp256k1::Error as SecpError;
  32 use bitcoin::secp256k1;
  33
  34 use prelude::*;
  35 use core::cmp;
  36 use ln::chan_utils;
  37 use util::transaction_utils::sort_outputs;
  38 use ln::channel::INITIAL_COMMITMENT_NUMBER;
  39 use core::ops::Deref;
  40 use chain;
  41
  42 pub(crate) const MAX_HTLCS: u16 = 483;
  43
  44 pub(super) const HTLC_SUCCESS_TX_WEIGHT: u64 = 703;
  45 pub(super) const HTLC_TIMEOUT_TX_WEIGHT: u64 = 663;
  46
  47 #[derive(PartialEq)]
  48 pub(crate) enum HTLCType {
  49         AcceptedHTLC,
  50         OfferedHTLC
  51 }
  52
  53 impl HTLCType {
  54         /// Check if a given tx witnessScript len matchs one of a pre-signed HTLC
  55         pub(crate) fn scriptlen_to_htlctype(witness_script_len: usize) ->  Option<HTLCType> {
  56                 if witness_script_len == 133 {
  57                         Some(HTLCType::OfferedHTLC)
  58                 } else if witness_script_len >= 136 && witness_script_len <= 139 {
  59                         Some(HTLCType::AcceptedHTLC)
  60                 } else {
  61                         None
  62                 }
  63         }
  64 }
  65
  66 // Various functions for key derivation and transaction creation for use within channels. Primarily
  67 // used in Channel and ChannelMonitor.
  68
  69 /// Build the commitment secret from the seed and the commitment number
  70 pub fn build_commitment_secret(commitment_seed: &[u8; 32], idx: u64) -> [u8; 32] {
  71         let mut res: [u8; 32] = commitment_seed.clone();
  72         for i in 0..48 {
  73                 let bitpos = 47 - i;
  74                 if idx & (1 << bitpos) == (1 << bitpos) {
  75                         res[bitpos / 8] ^= 1 << (bitpos & 7);
  76                         res = Sha256::hash(&res).into_inner();
  77                 }
  78         }
  79         res
  80 }
  81
  82 /// Implements the per-commitment secret storage scheme from
  83 /// [BOLT 3](https://github.com/lightningnetwork/lightning-rfc/blob/dcbf8583976df087c79c3ce0b535311212e6812d/03-transactions.md#efficient-per-commitment-secret-storage).
  84 ///
  85 /// Allows us to keep track of all of the revocation secrets of counterarties in just 50*32 bytes
  86 /// or so.
  87 #[derive(Clone)]
  88 pub(crate) struct CounterpartyCommitmentSecrets {
  89         old_secrets: [([u8; 32], u64); 49],
  90 }
  91
  92 impl PartialEq for CounterpartyCommitmentSecrets {
  93         fn eq(&self, other: &Self) -> bool {
  94                 for (&(ref secret, ref idx), &(ref o_secret, ref o_idx)) in self.old_secrets.iter().zip(other.old_secrets.iter()) {
  95                         if secret != o_secret || idx != o_idx {
  96                                 return false
  97                         }
  98                 }
  99                 true
 100         }
 101 }
 102
 103 impl CounterpartyCommitmentSecrets {
 104         pub(crate) fn new() -> Self {
 105                 Self { old_secrets: [([0; 32], 1 << 48); 49], }
 106         }
 107
 108         #[inline]
 109         fn place_secret(idx: u64) -> u8 {
 110                 for i in 0..48 {
 111                         if idx & (1 << i) == (1 << i) {
 112                                 return i
 113                         }
 114                 }
 115                 48
 116         }
 117
 118         pub(crate) fn get_min_seen_secret(&self) -> u64 {
 119                 //TODO This can be optimized?
 120                 let mut min = 1 << 48;
 121                 for &(_, idx) in self.old_secrets.iter() {
 122                         if idx < min {
 123                                 min = idx;
 124                         }
 125                 }
 126                 min
 127         }
 128
 129         #[inline]
 130         fn derive_secret(secret: [u8; 32], bits: u8, idx: u64) -> [u8; 32] {
 131                 let mut res: [u8; 32] = secret;
 132                 for i in 0..bits {
 133                         let bitpos = bits - 1 - i;
 134                         if idx & (1 << bitpos) == (1 << bitpos) {
 135                                 res[(bitpos / 8) as usize] ^= 1 << (bitpos & 7);
 136                                 res = Sha256::hash(&res).into_inner();
 137                         }
 138                 }
 139                 res
 140         }
 141
 142         pub(crate) fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), ()> {
 143                 let pos = Self::place_secret(idx);
 144                 for i in 0..pos {
 145                         let (old_secret, old_idx) = self.old_secrets[i as usize];
 146                         if Self::derive_secret(secret, pos, old_idx) != old_secret {
 147                                 return Err(());
 148                         }
 149                 }
 150                 if self.get_min_seen_secret() <= idx {
 151                         return Ok(());
 152                 }
 153                 self.old_secrets[pos as usize] = (secret, idx);
 154                 Ok(())
 155         }
 156
 157         /// Can only fail if idx is < get_min_seen_secret
 158         pub(crate) fn get_secret(&self, idx: u64) -> Option<[u8; 32]> {
 159                 for i in 0..self.old_secrets.len() {
 160                         if (idx & (!((1 << i) - 1))) == self.old_secrets[i].1 {
 161                                 return Some(Self::derive_secret(self.old_secrets[i].0, i as u8, idx))
 162                         }
 163                 }
 164                 assert!(idx < self.get_min_seen_secret());
 165                 None
 166         }
 167 }
 168
 169 impl Writeable for CounterpartyCommitmentSecrets {
 170         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
 171                 for &(ref secret, ref idx) in self.old_secrets.iter() {
 172                         writer.write_all(secret)?;
 173                         writer.write_all(&byte_utils::be64_to_array(*idx))?;
 174                 }
 175                 write_tlv_fields!(writer, {}, {});
 176                 Ok(())
 177         }
 178 }
 179 impl Readable for CounterpartyCommitmentSecrets {
 180         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
 181                 let mut old_secrets = [([0; 32], 1 << 48); 49];
 182                 for &mut (ref mut secret, ref mut idx) in old_secrets.iter_mut() {
 183                         *secret = Readable::read(reader)?;
 184                         *idx = Readable::read(reader)?;
 185                 }
 186                 read_tlv_fields!(reader, {}, {});
 187                 Ok(Self { old_secrets })
 188         }
 189 }
 190
 191 /// Derives a per-commitment-transaction private key (eg an htlc key or delayed_payment key)
 192 /// from the base secret and the per_commitment_point.
 193 ///
 194 /// Note that this is infallible iff we trust that at least one of the two input keys are randomly
 195 /// generated (ie our own).
 196 pub fn derive_private_key<T: secp256k1::Signing>(secp_ctx: &Secp256k1<T>, per_commitment_point: &PublicKey, base_secret: &SecretKey) -> Result<SecretKey, SecpError> {
 197         let mut sha = Sha256::engine();
 198         sha.input(&per_commitment_point.serialize());
 199         sha.input(&PublicKey::from_secret_key(&secp_ctx, &base_secret).serialize());
 200         let res = Sha256::from_engine(sha).into_inner();
 201
 202         let mut key = base_secret.clone();
 203         key.add_assign(&res)?;
 204         Ok(key)
 205 }
 206
 207 /// Derives a per-commitment-transaction public key (eg an htlc key or a delayed_payment key)
 208 /// from the base point and the per_commitment_key. This is the public equivalent of
 209 /// derive_private_key - using only public keys to derive a public key instead of private keys.
 210 ///
 211 /// Note that this is infallible iff we trust that at least one of the two input keys are randomly
 212 /// generated (ie our own).
 213 pub fn derive_public_key<T: secp256k1::Signing>(secp_ctx: &Secp256k1<T>, per_commitment_point: &PublicKey, base_point: &PublicKey) -> Result<PublicKey, SecpError> {
 214         let mut sha = Sha256::engine();
 215         sha.input(&per_commitment_point.serialize());
 216         sha.input(&base_point.serialize());
 217         let res = Sha256::from_engine(sha).into_inner();
 218
 219         let hashkey = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&res)?);
 220         base_point.combine(&hashkey)
 221 }
 222
 223 /// Derives a per-commitment-transaction revocation key from its constituent parts.
 224 ///
 225 /// Only the cheating participant owns a valid witness to propagate a revoked
 226 /// commitment transaction, thus per_commitment_secret always come from cheater
 227 /// and revocation_base_secret always come from punisher, which is the broadcaster
 228 /// of the transaction spending with this key knowledge.
 229 ///
 230 /// Note that this is infallible iff we trust that at least one of the two input keys are randomly
 231 /// generated (ie our own).
 232 pub fn derive_private_revocation_key<T: secp256k1::Signing>(secp_ctx: &Secp256k1<T>, per_commitment_secret: &SecretKey, countersignatory_revocation_base_secret: &SecretKey) -> Result<SecretKey, SecpError> {
 233         let countersignatory_revocation_base_point = PublicKey::from_secret_key(&secp_ctx, &countersignatory_revocation_base_secret);
 234         let per_commitment_point = PublicKey::from_secret_key(&secp_ctx, &per_commitment_secret);
 235
 236         let rev_append_commit_hash_key = {
 237                 let mut sha = Sha256::engine();
 238                 sha.input(&countersignatory_revocation_base_point.serialize());
 239                 sha.input(&per_commitment_point.serialize());
 240
 241                 Sha256::from_engine(sha).into_inner()
 242         };
 243         let commit_append_rev_hash_key = {
 244                 let mut sha = Sha256::engine();
 245                 sha.input(&per_commitment_point.serialize());
 246                 sha.input(&countersignatory_revocation_base_point.serialize());
 247
 248                 Sha256::from_engine(sha).into_inner()
 249         };
 250
 251         let mut countersignatory_contrib = countersignatory_revocation_base_secret.clone();
 252         countersignatory_contrib.mul_assign(&rev_append_commit_hash_key)?;
 253         let mut broadcaster_contrib = per_commitment_secret.clone();
 254         broadcaster_contrib.mul_assign(&commit_append_rev_hash_key)?;
 255         countersignatory_contrib.add_assign(&broadcaster_contrib[..])?;
 256         Ok(countersignatory_contrib)
 257 }
 258
 259 /// Derives a per-commitment-transaction revocation public key from its constituent parts. This is
 260 /// the public equivalend of derive_private_revocation_key - using only public keys to derive a
 261 /// public key instead of private keys.
 262 ///
 263 /// Only the cheating participant owns a valid witness to propagate a revoked
 264 /// commitment transaction, thus per_commitment_point always come from cheater
 265 /// and revocation_base_point always come from punisher, which is the broadcaster
 266 /// of the transaction spending with this key knowledge.
 267 ///
 268 /// Note that this is infallible iff we trust that at least one of the two input keys are randomly
 269 /// generated (ie our own).
 270 pub fn derive_public_revocation_key<T: secp256k1::Verification>(secp_ctx: &Secp256k1<T>, per_commitment_point: &PublicKey, countersignatory_revocation_base_point: &PublicKey) -> Result<PublicKey, SecpError> {
 271         let rev_append_commit_hash_key = {
 272                 let mut sha = Sha256::engine();
 273                 sha.input(&countersignatory_revocation_base_point.serialize());
 274                 sha.input(&per_commitment_point.serialize());
 275
 276                 Sha256::from_engine(sha).into_inner()
 277         };
 278         let commit_append_rev_hash_key = {
 279                 let mut sha = Sha256::engine();
 280                 sha.input(&per_commitment_point.serialize());
 281                 sha.input(&countersignatory_revocation_base_point.serialize());
 282
 283                 Sha256::from_engine(sha).into_inner()
 284         };
 285
 286         let mut countersignatory_contrib = countersignatory_revocation_base_point.clone();
 287         countersignatory_contrib.mul_assign(&secp_ctx, &rev_append_commit_hash_key)?;
 288         let mut broadcaster_contrib = per_commitment_point.clone();
 289         broadcaster_contrib.mul_assign(&secp_ctx, &commit_append_rev_hash_key)?;
 290         countersignatory_contrib.combine(&broadcaster_contrib)
 291 }
 292
 293 /// The set of public keys which are used in the creation of one commitment transaction.
 294 /// These are derived from the channel base keys and per-commitment data.
 295 ///
 296 /// A broadcaster key is provided from potential broadcaster of the computed transaction.
 297 /// A countersignatory key is coming from a protocol participant unable to broadcast the
 298 /// transaction.
 299 ///
 300 /// These keys are assumed to be good, either because the code derived them from
 301 /// channel basepoints via the new function, or they were obtained via
 302 /// CommitmentTransaction.trust().keys() because we trusted the source of the
 303 /// pre-calculated keys.
 304 #[derive(PartialEq, Clone)]
 305 pub struct TxCreationKeys {
 306         /// The broadcaster's per-commitment public key which was used to derive the other keys.
 307         pub per_commitment_point: PublicKey,
 308         /// The revocation key which is used to allow the broadcaster of the commitment
 309         /// transaction to provide their counterparty the ability to punish them if they broadcast
 310         /// an old state.
 311         pub revocation_key: PublicKey,
 312         /// Broadcaster's HTLC Key
 313         pub broadcaster_htlc_key: PublicKey,
 314         /// Countersignatory's HTLC Key
 315         pub countersignatory_htlc_key: PublicKey,
 316         /// Broadcaster's Payment Key (which isn't allowed to be spent from for some delay)
 317         pub broadcaster_delayed_payment_key: PublicKey,
 318 }
 319
 320 impl_writeable_tlv_based!(TxCreationKeys, {
 321         (0, per_commitment_point),
 322         (2, revocation_key),
 323         (4, broadcaster_htlc_key),
 324         (6, countersignatory_htlc_key),
 325         (8, broadcaster_delayed_payment_key),
 326 }, {}, {});
 327
 328 /// One counterparty's public keys which do not change over the life of a channel.
 329 #[derive(Clone, PartialEq)]
 330 pub struct ChannelPublicKeys {
 331         /// The public key which is used to sign all commitment transactions, as it appears in the
 332         /// on-chain channel lock-in 2-of-2 multisig output.
 333         pub funding_pubkey: PublicKey,
 334         /// The base point which is used (with derive_public_revocation_key) to derive per-commitment
 335         /// revocation keys. This is combined with the per-commitment-secret generated by the
 336         /// counterparty to create a secret which the counterparty can reveal to revoke previous
 337         /// states.
 338         pub revocation_basepoint: PublicKey,
 339         /// The public key on which the non-broadcaster (ie the countersignatory) receives an immediately
 340         /// spendable primary channel balance on the broadcaster's commitment transaction. This key is
 341         /// static across every commitment transaction.
 342         pub payment_point: PublicKey,
 343         /// The base point which is used (with derive_public_key) to derive a per-commitment payment
 344         /// public key which receives non-HTLC-encumbered funds which are only available for spending
 345         /// after some delay (or can be claimed via the revocation path).
 346         pub delayed_payment_basepoint: PublicKey,
 347         /// The base point which is used (with derive_public_key) to derive a per-commitment public key
 348         /// which is used to encumber HTLC-in-flight outputs.
 349         pub htlc_basepoint: PublicKey,
 350 }
 351
 352 impl_writeable_tlv_based!(ChannelPublicKeys, {
 353         (0, funding_pubkey),
 354         (2, revocation_basepoint),
 355         (4, payment_point),
 356         (6, delayed_payment_basepoint),
 357         (8, htlc_basepoint),
 358 }, {}, {});
 359
 360 impl TxCreationKeys {
 361         /// Create per-state keys from channel base points and the per-commitment point.
 362         /// Key set is asymmetric and can't be used as part of counter-signatory set of transactions.
 363         pub fn derive_new<T: secp256k1::Signing + secp256k1::Verification>(secp_ctx: &Secp256k1<T>, per_commitment_point: &PublicKey, broadcaster_delayed_payment_base: &PublicKey, broadcaster_htlc_base: &PublicKey, countersignatory_revocation_base: &PublicKey, countersignatory_htlc_base: &PublicKey) -> Result<TxCreationKeys, SecpError> {
 364                 Ok(TxCreationKeys {
 365                         per_commitment_point: per_commitment_point.clone(),
 366                         revocation_key: derive_public_revocation_key(&secp_ctx, &per_commitment_point, &countersignatory_revocation_base)?,
 367                         broadcaster_htlc_key: derive_public_key(&secp_ctx, &per_commitment_point, &broadcaster_htlc_base)?,
 368                         countersignatory_htlc_key: derive_public_key(&secp_ctx, &per_commitment_point, &countersignatory_htlc_base)?,
 369                         broadcaster_delayed_payment_key: derive_public_key(&secp_ctx, &per_commitment_point, &broadcaster_delayed_payment_base)?,
 370                 })
 371         }
 372
 373         /// Generate per-state keys from channel static keys.
 374         /// Key set is asymmetric and can't be used as part of counter-signatory set of transactions.
 375         pub fn from_channel_static_keys<T: secp256k1::Signing + secp256k1::Verification>(per_commitment_point: &PublicKey, broadcaster_keys: &ChannelPublicKeys, countersignatory_keys: &ChannelPublicKeys, secp_ctx: &Secp256k1<T>) -> Result<TxCreationKeys, SecpError> {
 376                 TxCreationKeys::derive_new(
 377                         &secp_ctx,
 378                         &per_commitment_point,
 379                         &broadcaster_keys.delayed_payment_basepoint,
 380                         &broadcaster_keys.htlc_basepoint,
 381                         &countersignatory_keys.revocation_basepoint,
 382                         &countersignatory_keys.htlc_basepoint,
 383                 )
 384         }
 385 }
 386
 387 /// The maximum length of a script returned by get_revokeable_redeemscript.
 388 // Calculated as 6 bytes of opcodes, 1 byte push plus 2 bytes for contest_delay, and two public
 389 // keys of 33 bytes (+ 1 push).
 390 pub const REVOKEABLE_REDEEMSCRIPT_MAX_LENGTH: usize = 6 + 3 + 34*2;
 391
 392 /// A script either spendable by the revocation
 393 /// key or the broadcaster_delayed_payment_key and satisfying the relative-locktime OP_CSV constrain.
 394 /// Encumbering a `to_holder` output on a commitment transaction or 2nd-stage HTLC transactions.
 395 pub fn get_revokeable_redeemscript(revocation_key: &PublicKey, contest_delay: u16, broadcaster_delayed_payment_key: &PublicKey) -> Script {
 396         let res = Builder::new().push_opcode(opcodes::all::OP_IF)
 397                       .push_slice(&revocation_key.serialize())
 398                       .push_opcode(opcodes::all::OP_ELSE)
 399                       .push_int(contest_delay as i64)
 400                       .push_opcode(opcodes::all::OP_CSV)
 401                       .push_opcode(opcodes::all::OP_DROP)
 402                       .push_slice(&broadcaster_delayed_payment_key.serialize())
 403                       .push_opcode(opcodes::all::OP_ENDIF)
 404                       .push_opcode(opcodes::all::OP_CHECKSIG)
 405                       .into_script();
 406         debug_assert!(res.len() <= REVOKEABLE_REDEEMSCRIPT_MAX_LENGTH);
 407         res
 408 }
 409
 410 #[derive(Clone, PartialEq)]
 411 /// Information about an HTLC as it appears in a commitment transaction
 412 pub struct HTLCOutputInCommitment {
 413         /// Whether the HTLC was "offered" (ie outbound in relation to this commitment transaction).
 414         /// Note that this is not the same as whether it is ountbound *from us*. To determine that you
 415         /// need to compare this value to whether the commitment transaction in question is that of
 416         /// the counterparty or our own.
 417         pub offered: bool,
 418         /// The value, in msat, of the HTLC. The value as it appears in the commitment transaction is
 419         /// this divided by 1000.
 420         pub amount_msat: u64,
 421         /// The CLTV lock-time at which this HTLC expires.
 422         pub cltv_expiry: u32,
 423         /// The hash of the preimage which unlocks this HTLC.
 424         pub payment_hash: PaymentHash,
 425         /// The position within the commitment transactions' outputs. This may be None if the value is
 426         /// below the dust limit (in which case no output appears in the commitment transaction and the
 427         /// value is spent to additional transaction fees).
 428         pub transaction_output_index: Option<u32>,
 429 }
 430
 431 impl_writeable_tlv_based!(HTLCOutputInCommitment, {
 432         (0, offered),
 433         (2, amount_msat),
 434         (4, cltv_expiry),
 435         (6, payment_hash),
 436 }, {
 437         (8, transaction_output_index)
 438 }, {});
 439
 440 #[inline]
 441 pub(crate) fn get_htlc_redeemscript_with_explicit_keys(htlc: &HTLCOutputInCommitment, broadcaster_htlc_key: &PublicKey, countersignatory_htlc_key: &PublicKey, revocation_key: &PublicKey) -> Script {
 442         let payment_hash160 = Ripemd160::hash(&htlc.payment_hash.0[..]).into_inner();
 443         if htlc.offered {
 444                 Builder::new().push_opcode(opcodes::all::OP_DUP)
 445                               .push_opcode(opcodes::all::OP_HASH160)
 446                               .push_slice(&PubkeyHash::hash(&revocation_key.serialize())[..])
 447                               .push_opcode(opcodes::all::OP_EQUAL)
 448                               .push_opcode(opcodes::all::OP_IF)
 449                               .push_opcode(opcodes::all::OP_CHECKSIG)
 450                               .push_opcode(opcodes::all::OP_ELSE)
 451                               .push_slice(&countersignatory_htlc_key.serialize()[..])
 452                               .push_opcode(opcodes::all::OP_SWAP)
 453                               .push_opcode(opcodes::all::OP_SIZE)
 454                               .push_int(32)
 455                               .push_opcode(opcodes::all::OP_EQUAL)
 456                               .push_opcode(opcodes::all::OP_NOTIF)
 457                               .push_opcode(opcodes::all::OP_DROP)
 458                               .push_int(2)
 459                               .push_opcode(opcodes::all::OP_SWAP)
 460                               .push_slice(&broadcaster_htlc_key.serialize()[..])
 461                               .push_int(2)
 462                               .push_opcode(opcodes::all::OP_CHECKMULTISIG)
 463                               .push_opcode(opcodes::all::OP_ELSE)
 464                               .push_opcode(opcodes::all::OP_HASH160)
 465                               .push_slice(&payment_hash160)
 466                               .push_opcode(opcodes::all::OP_EQUALVERIFY)
 467                               .push_opcode(opcodes::all::OP_CHECKSIG)
 468                               .push_opcode(opcodes::all::OP_ENDIF)
 469                               .push_opcode(opcodes::all::OP_ENDIF)
 470                               .into_script()
 471         } else {
 472                 Builder::new().push_opcode(opcodes::all::OP_DUP)
 473                               .push_opcode(opcodes::all::OP_HASH160)
 474                               .push_slice(&PubkeyHash::hash(&revocation_key.serialize())[..])
 475                               .push_opcode(opcodes::all::OP_EQUAL)
 476                               .push_opcode(opcodes::all::OP_IF)
 477                               .push_opcode(opcodes::all::OP_CHECKSIG)
 478                               .push_opcode(opcodes::all::OP_ELSE)
 479                               .push_slice(&countersignatory_htlc_key.serialize()[..])
 480                               .push_opcode(opcodes::all::OP_SWAP)
 481                               .push_opcode(opcodes::all::OP_SIZE)
 482                               .push_int(32)
 483                               .push_opcode(opcodes::all::OP_EQUAL)
 484                               .push_opcode(opcodes::all::OP_IF)
 485                               .push_opcode(opcodes::all::OP_HASH160)
 486                               .push_slice(&payment_hash160)
 487                               .push_opcode(opcodes::all::OP_EQUALVERIFY)
 488                               .push_int(2)
 489                               .push_opcode(opcodes::all::OP_SWAP)
 490                               .push_slice(&broadcaster_htlc_key.serialize()[..])
 491                               .push_int(2)
 492                               .push_opcode(opcodes::all::OP_CHECKMULTISIG)
 493                               .push_opcode(opcodes::all::OP_ELSE)
 494                               .push_opcode(opcodes::all::OP_DROP)
 495                               .push_int(htlc.cltv_expiry as i64)
 496                               .push_opcode(opcodes::all::OP_CLTV)
 497                               .push_opcode(opcodes::all::OP_DROP)
 498                               .push_opcode(opcodes::all::OP_CHECKSIG)
 499                               .push_opcode(opcodes::all::OP_ENDIF)
 500                               .push_opcode(opcodes::all::OP_ENDIF)
 501                               .into_script()
 502         }
 503 }
 504
 505 /// Gets the witness redeemscript for an HTLC output in a commitment transaction. Note that htlc
 506 /// does not need to have its previous_output_index filled.
 507 #[inline]
 508 pub fn get_htlc_redeemscript(htlc: &HTLCOutputInCommitment, keys: &TxCreationKeys) -> Script {
 509         get_htlc_redeemscript_with_explicit_keys(htlc, &keys.broadcaster_htlc_key, &keys.countersignatory_htlc_key, &keys.revocation_key)
 510 }
 511
 512 /// Gets the redeemscript for a funding output from the two funding public keys.
 513 /// Note that the order of funding public keys does not matter.
 514 pub fn make_funding_redeemscript(broadcaster: &PublicKey, countersignatory: &PublicKey) -> Script {
 515         let broadcaster_funding_key = broadcaster.serialize();
 516         let countersignatory_funding_key = countersignatory.serialize();
 517
 518         let builder = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2);
 519         if broadcaster_funding_key[..] < countersignatory_funding_key[..] {
 520                 builder.push_slice(&broadcaster_funding_key)
 521                         .push_slice(&countersignatory_funding_key)
 522         } else {
 523                 builder.push_slice(&countersignatory_funding_key)
 524                         .push_slice(&broadcaster_funding_key)
 525         }.push_opcode(opcodes::all::OP_PUSHNUM_2).push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script()
 526 }
 527
 528 /// Builds an unsigned HTLC-Success or HTLC-Timeout transaction from the given channel and HTLC
 529 /// parameters. This is used by [`TrustedCommitmentTransaction::get_htlc_sigs`] to fetch the
 530 /// transaction which needs signing, and can be used to construct an HTLC transaction which is
 531 /// broadcastable given a counterparty HTLC signature.
 532 ///
 533 /// Panics if htlc.transaction_output_index.is_none() (as such HTLCs do not appear in the
 534 /// commitment transaction).
 535 pub fn build_htlc_transaction(commitment_txid: &Txid, feerate_per_kw: u32, contest_delay: u16, htlc: &HTLCOutputInCommitment, broadcaster_delayed_payment_key: &PublicKey, revocation_key: &PublicKey) -> Transaction {
 536         let mut txins: Vec<TxIn> = Vec::new();
 537         txins.push(TxIn {
 538                 previous_output: OutPoint {
 539                         txid: commitment_txid.clone(),
 540                         vout: htlc.transaction_output_index.expect("Can't build an HTLC transaction for a dust output"),
 541                 },
 542                 script_sig: Script::new(),
 543                 sequence: 0,
 544                 witness: Vec::new(),
 545         });
 546
 547         let total_fee = if htlc.offered {
 548                         feerate_per_kw as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000
 549                 } else {
 550                         feerate_per_kw as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000
 551                 };
 552
 553         let mut txouts: Vec<TxOut> = Vec::new();
 554         txouts.push(TxOut {
 555                 script_pubkey: get_revokeable_redeemscript(revocation_key, contest_delay, broadcaster_delayed_payment_key).to_v0_p2wsh(),
 556                 value: htlc.amount_msat / 1000 - total_fee //TODO: BOLT 3 does not specify if we should add amount_msat before dividing or if we should divide by 1000 before subtracting (as we do here)
 557         });
 558
 559         Transaction {
 560                 version: 2,
 561                 lock_time: if htlc.offered { htlc.cltv_expiry } else { 0 },
 562                 input: txins,
 563                 output: txouts,
 564         }
 565 }
 566
 567 /// Per-channel data used to build transactions in conjunction with the per-commitment data (CommitmentTransaction).
 568 /// The fields are organized by holder/counterparty.
 569 ///
 570 /// Normally, this is converted to the broadcaster/countersignatory-organized DirectedChannelTransactionParameters
 571 /// before use, via the as_holder_broadcastable and as_counterparty_broadcastable functions.
 572 #[derive(Clone)]
 573 pub struct ChannelTransactionParameters {
 574         /// Holder public keys
 575         pub holder_pubkeys: ChannelPublicKeys,
 576         /// The contest delay selected by the holder, which applies to counterparty-broadcast transactions
 577         pub holder_selected_contest_delay: u16,
 578         /// Whether the holder is the initiator of this channel.
 579         /// This is an input to the commitment number obscure factor computation.
 580         pub is_outbound_from_holder: bool,
 581         /// The late-bound counterparty channel transaction parameters.
 582         /// These parameters are populated at the point in the protocol where the counterparty provides them.
 583         pub counterparty_parameters: Option<CounterpartyChannelTransactionParameters>,
 584         /// The late-bound funding outpoint
 585         pub funding_outpoint: Option<chain::transaction::OutPoint>,
 586 }
 587
 588 /// Late-bound per-channel counterparty data used to build transactions.
 589 #[derive(Clone)]
 590 pub struct CounterpartyChannelTransactionParameters {
 591         /// Counter-party public keys
 592         pub pubkeys: ChannelPublicKeys,
 593         /// The contest delay selected by the counterparty, which applies to holder-broadcast transactions
 594         pub selected_contest_delay: u16,
 595 }
 596
 597 impl ChannelTransactionParameters {
 598         /// Whether the late bound parameters are populated.
 599         pub fn is_populated(&self) -> bool {
 600                 self.counterparty_parameters.is_some() && self.funding_outpoint.is_some()
 601         }
 602
 603         /// Convert the holder/counterparty parameters to broadcaster/countersignatory-organized parameters,
 604         /// given that the holder is the broadcaster.
 605         ///
 606         /// self.is_populated() must be true before calling this function.
 607         pub fn as_holder_broadcastable(&self) -> DirectedChannelTransactionParameters {
 608                 assert!(self.is_populated(), "self.late_parameters must be set before using as_holder_broadcastable");
 609                 DirectedChannelTransactionParameters {
 610                         inner: self,
 611                         holder_is_broadcaster: true
 612                 }
 613         }
 614
 615         /// Convert the holder/counterparty parameters to broadcaster/countersignatory-organized parameters,
 616         /// given that the counterparty is the broadcaster.
 617         ///
 618         /// self.is_populated() must be true before calling this function.
 619         pub fn as_counterparty_broadcastable(&self) -> DirectedChannelTransactionParameters {
 620                 assert!(self.is_populated(), "self.late_parameters must be set before using as_counterparty_broadcastable");
 621                 DirectedChannelTransactionParameters {
 622                         inner: self,
 623                         holder_is_broadcaster: false
 624                 }
 625         }
 626 }
 627
 628 impl_writeable_tlv_based!(CounterpartyChannelTransactionParameters, {
 629         (0, pubkeys),
 630         (2, selected_contest_delay),
 631 }, {}, {});
 632
 633 impl_writeable_tlv_based!(ChannelTransactionParameters, {
 634         (0, holder_pubkeys),
 635         (2, holder_selected_contest_delay),
 636         (4, is_outbound_from_holder),
 637 }, {
 638         (6, counterparty_parameters),
 639         (8, funding_outpoint),
 640 }, {});
 641
 642 /// Static channel fields used to build transactions given per-commitment fields, organized by
 643 /// broadcaster/countersignatory.
 644 ///
 645 /// This is derived from the holder/counterparty-organized ChannelTransactionParameters via the
 646 /// as_holder_broadcastable and as_counterparty_broadcastable functions.
 647 pub struct DirectedChannelTransactionParameters<'a> {
 648         /// The holder's channel static parameters
 649         inner: &'a ChannelTransactionParameters,
 650         /// Whether the holder is the broadcaster
 651         holder_is_broadcaster: bool,
 652 }
 653
 654 impl<'a> DirectedChannelTransactionParameters<'a> {
 655         /// Get the channel pubkeys for the broadcaster
 656         pub fn broadcaster_pubkeys(&self) -> &ChannelPublicKeys {
 657                 if self.holder_is_broadcaster {
 658                         &self.inner.holder_pubkeys
 659                 } else {
 660                         &self.inner.counterparty_parameters.as_ref().unwrap().pubkeys
 661                 }
 662         }
 663
 664         /// Get the channel pubkeys for the countersignatory
 665         pub fn countersignatory_pubkeys(&self) -> &ChannelPublicKeys {
 666                 if self.holder_is_broadcaster {
 667                         &self.inner.counterparty_parameters.as_ref().unwrap().pubkeys
 668                 } else {
 669                         &self.inner.holder_pubkeys
 670                 }
 671         }
 672
 673         /// Get the contest delay applicable to the transactions.
 674         /// Note that the contest delay was selected by the countersignatory.
 675         pub fn contest_delay(&self) -> u16 {
 676                 let counterparty_parameters = self.inner.counterparty_parameters.as_ref().unwrap();
 677                 if self.holder_is_broadcaster { counterparty_parameters.selected_contest_delay } else { self.inner.holder_selected_contest_delay }
 678         }
 679
 680         /// Whether the channel is outbound from the broadcaster.
 681         ///
 682         /// The boolean representing the side that initiated the channel is
 683         /// an input to the commitment number obscure factor computation.
 684         pub fn is_outbound(&self) -> bool {
 685                 if self.holder_is_broadcaster { self.inner.is_outbound_from_holder } else { !self.inner.is_outbound_from_holder }
 686         }
 687
 688         /// The funding outpoint
 689         pub fn funding_outpoint(&self) -> OutPoint {
 690                 self.inner.funding_outpoint.unwrap().into_bitcoin_outpoint()
 691         }
 692 }
 693
 694 /// Information needed to build and sign a holder's commitment transaction.
 695 ///
 696 /// The transaction is only signed once we are ready to broadcast.
 697 #[derive(Clone)]
 698 pub struct HolderCommitmentTransaction {
 699         inner: CommitmentTransaction,
 700         /// Our counterparty's signature for the transaction
 701         pub counterparty_sig: Signature,
 702         /// All non-dust counterparty HTLC signatures, in the order they appear in the transaction
 703         pub counterparty_htlc_sigs: Vec<Signature>,
 704         // Which order the signatures should go in when constructing the final commitment tx witness.
 705         // The user should be able to reconstruct this themselves, so we don't bother to expose it.
 706         holder_sig_first: bool,
 707 }
 708
 709 impl Deref for HolderCommitmentTransaction {
 710         type Target = CommitmentTransaction;
 711
 712         fn deref(&self) -> &Self::Target { &self.inner }
 713 }
 714
 715 impl PartialEq for HolderCommitmentTransaction {
 716         // We dont care whether we are signed in equality comparison
 717         fn eq(&self, o: &Self) -> bool {
 718                 self.inner == o.inner
 719         }
 720 }
 721
 722 impl_writeable_tlv_based!(HolderCommitmentTransaction, {
 723         (0, inner),
 724         (2, counterparty_sig),
 725         (4, holder_sig_first),
 726 }, {}, {
 727         (6, counterparty_htlc_sigs),
 728 });
 729
 730 impl HolderCommitmentTransaction {
 731         #[cfg(test)]
 732         pub fn dummy() -> Self {
 733                 let secp_ctx = Secp256k1::new();
 734                 let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
 735                 let dummy_sig = secp_ctx.sign(&secp256k1::Message::from_slice(&[42; 32]).unwrap(), &SecretKey::from_slice(&[42; 32]).unwrap());
 736
 737                 let keys = TxCreationKeys {
 738                         per_commitment_point: dummy_key.clone(),
 739                         revocation_key: dummy_key.clone(),
 740                         broadcaster_htlc_key: dummy_key.clone(),
 741                         countersignatory_htlc_key: dummy_key.clone(),
 742                         broadcaster_delayed_payment_key: dummy_key.clone(),
 743                 };
 744                 let channel_pubkeys = ChannelPublicKeys {
 745                         funding_pubkey: dummy_key.clone(),
 746                         revocation_basepoint: dummy_key.clone(),
 747                         payment_point: dummy_key.clone(),
 748                         delayed_payment_basepoint: dummy_key.clone(),
 749                         htlc_basepoint: dummy_key.clone()
 750                 };
 751                 let channel_parameters = ChannelTransactionParameters {
 752                         holder_pubkeys: channel_pubkeys.clone(),
 753                         holder_selected_contest_delay: 0,
 754                         is_outbound_from_holder: false,
 755                         counterparty_parameters: Some(CounterpartyChannelTransactionParameters { pubkeys: channel_pubkeys.clone(), selected_contest_delay: 0 }),
 756                         funding_outpoint: Some(chain::transaction::OutPoint { txid: Default::default(), index: 0 })
 757                 };
 758                 let mut htlcs_with_aux: Vec<(_, ())> = Vec::new();
 759                 let inner = CommitmentTransaction::new_with_auxiliary_htlc_data(0, 0, 0, keys, 0, &mut htlcs_with_aux, &channel_parameters.as_counterparty_broadcastable());
 760                 HolderCommitmentTransaction {
 761                         inner,
 762                         counterparty_sig: dummy_sig,
 763                         counterparty_htlc_sigs: Vec::new(),
 764                         holder_sig_first: false
 765                 }
 766         }
 767
 768         /// Create a new holder transaction with the given counterparty signatures.
 769         /// The funding keys are used to figure out which signature should go first when building the transaction for broadcast.
 770         pub fn new(commitment_tx: CommitmentTransaction, counterparty_sig: Signature, counterparty_htlc_sigs: Vec<Signature>, holder_funding_key: &PublicKey, counterparty_funding_key: &PublicKey) -> Self {
 771                 Self {
 772                         inner: commitment_tx,
 773                         counterparty_sig,
 774                         counterparty_htlc_sigs,
 775                         holder_sig_first: holder_funding_key.serialize()[..] < counterparty_funding_key.serialize()[..],
 776                 }
 777         }
 778
 779         pub(crate) fn add_holder_sig(&self, funding_redeemscript: &Script, holder_sig: Signature) -> Transaction {
 780                 // First push the multisig dummy, note that due to BIP147 (NULLDUMMY) it must be a zero-length element.
 781                 let mut tx = self.inner.built.transaction.clone();
 782                 tx.input[0].witness.push(Vec::new());
 783
 784                 if self.holder_sig_first {
 785                         tx.input[0].witness.push(holder_sig.serialize_der().to_vec());
 786                         tx.input[0].witness.push(self.counterparty_sig.serialize_der().to_vec());
 787                 } else {
 788                         tx.input[0].witness.push(self.counterparty_sig.serialize_der().to_vec());
 789                         tx.input[0].witness.push(holder_sig.serialize_der().to_vec());
 790                 }
 791                 tx.input[0].witness[1].push(SigHashType::All as u8);
 792                 tx.input[0].witness[2].push(SigHashType::All as u8);
 793
 794                 tx.input[0].witness.push(funding_redeemscript.as_bytes().to_vec());
 795                 tx
 796         }
 797 }
 798
 799 /// A pre-built Bitcoin commitment transaction and its txid.
 800 #[derive(Clone)]
 801 pub struct BuiltCommitmentTransaction {
 802         /// The commitment transaction
 803         pub transaction: Transaction,
 804         /// The txid for the commitment transaction.
 805         ///
 806         /// This is provided as a performance optimization, instead of calling transaction.txid()
 807         /// multiple times.
 808         pub txid: Txid,
 809 }
 810
 811 impl_writeable_tlv_based!(BuiltCommitmentTransaction, {
 812         (0, transaction),
 813         (2, txid)
 814 }, {}, {});
 815
 816 impl BuiltCommitmentTransaction {
 817         /// Get the SIGHASH_ALL sighash value of the transaction.
 818         ///
 819         /// This can be used to verify a signature.
 820         pub fn get_sighash_all(&self, funding_redeemscript: &Script, channel_value_satoshis: u64) -> Message {
 821                 let sighash = &bip143::SigHashCache::new(&self.transaction).signature_hash(0, funding_redeemscript, channel_value_satoshis, SigHashType::All)[..];
 822                 hash_to_message!(sighash)
 823         }
 824
 825         /// Sign a transaction, either because we are counter-signing the counterparty's transaction or
 826         /// because we are about to broadcast a holder transaction.
 827         pub fn sign<T: secp256k1::Signing>(&self, funding_key: &SecretKey, funding_redeemscript: &Script, channel_value_satoshis: u64, secp_ctx: &Secp256k1<T>) -> Signature {
 828                 let sighash = self.get_sighash_all(funding_redeemscript, channel_value_satoshis);
 829                 secp_ctx.sign(&sighash, funding_key)
 830         }
 831 }
 832
 833 /// This class tracks the per-transaction information needed to build a commitment transaction and to
 834 /// actually build it and sign.  It is used for holder transactions that we sign only when needed
 835 /// and for transactions we sign for the counterparty.
 836 ///
 837 /// This class can be used inside a signer implementation to generate a signature given the relevant
 838 /// secret key.
 839 #[derive(Clone)]
 840 pub struct CommitmentTransaction {
 841         commitment_number: u64,
 842         to_broadcaster_value_sat: u64,
 843         to_countersignatory_value_sat: u64,
 844         feerate_per_kw: u32,
 845         htlcs: Vec<HTLCOutputInCommitment>,
 846         // A cache of the parties' pubkeys required to construct the transaction, see doc for trust()
 847         keys: TxCreationKeys,
 848         // For access to the pre-built transaction, see doc for trust()
 849         built: BuiltCommitmentTransaction,
 850 }
 851
 852 impl PartialEq for CommitmentTransaction {
 853         fn eq(&self, o: &Self) -> bool {
 854                 let eq = self.commitment_number == o.commitment_number &&
 855                         self.to_broadcaster_value_sat == o.to_broadcaster_value_sat &&
 856                         self.to_countersignatory_value_sat == o.to_countersignatory_value_sat &&
 857                         self.feerate_per_kw == o.feerate_per_kw &&
 858                         self.htlcs == o.htlcs &&
 859                         self.keys == o.keys;
 860                 if eq {
 861                         debug_assert_eq!(self.built.transaction, o.built.transaction);
 862                         debug_assert_eq!(self.built.txid, o.built.txid);
 863                 }
 864                 eq
 865         }
 866 }
 867
 868 impl_writeable_tlv_based!(CommitmentTransaction, {
 869         (0, commitment_number),
 870         (2, to_broadcaster_value_sat),
 871         (4, to_countersignatory_value_sat),
 872         (6, feerate_per_kw),
 873         (8, keys),
 874         (10, built),
 875 }, {}, {
 876         (12, htlcs),
 877 });
 878
 879 impl CommitmentTransaction {
 880         /// Construct an object of the class while assigning transaction output indices to HTLCs.
 881         ///
 882         /// Populates HTLCOutputInCommitment.transaction_output_index in htlcs_with_aux.
 883         ///
 884         /// The generic T allows the caller to match the HTLC output index with auxiliary data.
 885         /// This auxiliary data is not stored in this object.
 886         ///
 887         /// Only include HTLCs that are above the dust limit for the channel.
 888         ///
 889         /// (C-not exported) due to the generic though we likely should expose a version without
 890         pub fn new_with_auxiliary_htlc_data<T>(commitment_number: u64, to_broadcaster_value_sat: u64, to_countersignatory_value_sat: u64, keys: TxCreationKeys, feerate_per_kw: u32, htlcs_with_aux: &mut Vec<(HTLCOutputInCommitment, T)>, channel_parameters: &DirectedChannelTransactionParameters) -> CommitmentTransaction {
 891                 // Sort outputs and populate output indices while keeping track of the auxiliary data
 892                 let (outputs, htlcs) = Self::internal_build_outputs(&keys, to_broadcaster_value_sat, to_countersignatory_value_sat, htlcs_with_aux, channel_parameters).unwrap();
 893
 894                 let (obscured_commitment_transaction_number, txins) = Self::internal_build_inputs(commitment_number, channel_parameters);
 895                 let transaction = Self::make_transaction(obscured_commitment_transaction_number, txins, outputs);
 896                 let txid = transaction.txid();
 897                 CommitmentTransaction {
 898                         commitment_number,
 899                         to_broadcaster_value_sat,
 900                         to_countersignatory_value_sat,
 901                         feerate_per_kw,
 902                         htlcs,
 903                         keys,
 904                         built: BuiltCommitmentTransaction {
 905                                 transaction,
 906                                 txid
 907                         },
 908                 }
 909         }
 910
 911         fn internal_rebuild_transaction(&self, keys: &TxCreationKeys, channel_parameters: &DirectedChannelTransactionParameters) -> Result<BuiltCommitmentTransaction, ()> {
 912                 let (obscured_commitment_transaction_number, txins) = Self::internal_build_inputs(self.commitment_number, channel_parameters);
 913
 914                 let mut htlcs_with_aux = self.htlcs.iter().map(|h| (h.clone(), ())).collect();
 915                 let (outputs, _) = Self::internal_build_outputs(keys, self.to_broadcaster_value_sat, self.to_countersignatory_value_sat, &mut htlcs_with_aux, channel_parameters)?;
 916
 917                 let transaction = Self::make_transaction(obscured_commitment_transaction_number, txins, outputs);
 918                 let txid = transaction.txid();
 919                 let built_transaction = BuiltCommitmentTransaction {
 920                         transaction,
 921                         txid
 922                 };
 923                 Ok(built_transaction)
 924         }
 925
 926         fn make_transaction(obscured_commitment_transaction_number: u64, txins: Vec<TxIn>, outputs: Vec<TxOut>) -> Transaction {
 927                 Transaction {
 928                         version: 2,
 929                         lock_time: ((0x20 as u32) << 8 * 3) | ((obscured_commitment_transaction_number & 0xffffffu64) as u32),
 930                         input: txins,
 931                         output: outputs,
 932                 }
 933         }
 934
 935         // This is used in two cases:
 936         // - initial sorting of outputs / HTLCs in the constructor, in which case T is auxiliary data the
 937         //   caller needs to have sorted together with the HTLCs so it can keep track of the output index
 938         // - building of a bitcoin transaction during a verify() call, in which case T is just ()
 939         fn internal_build_outputs<T>(keys: &TxCreationKeys, to_broadcaster_value_sat: u64, to_countersignatory_value_sat: u64, htlcs_with_aux: &mut Vec<(HTLCOutputInCommitment, T)>, channel_parameters: &DirectedChannelTransactionParameters) -> Result<(Vec<TxOut>, Vec<HTLCOutputInCommitment>), ()> {
 940                 let countersignatory_pubkeys = channel_parameters.countersignatory_pubkeys();
 941                 let contest_delay = channel_parameters.contest_delay();
 942
 943                 let mut txouts: Vec<(TxOut, Option<&mut HTLCOutputInCommitment>)> = Vec::new();
 944
 945                 if to_countersignatory_value_sat > 0 {
 946                         let script = script_for_p2wpkh(&countersignatory_pubkeys.payment_point);
 947                         txouts.push((
 948                                 TxOut {
 949                                         script_pubkey: script.clone(),
 950                                         value: to_countersignatory_value_sat,
 951                                 },
 952                                 None,
 953                         ))
 954                 }
 955
 956                 if to_broadcaster_value_sat > 0 {
 957                         let redeem_script = get_revokeable_redeemscript(
 958                                 &keys.revocation_key,
 959                                 contest_delay,
 960                                 &keys.broadcaster_delayed_payment_key,
 961                         );
 962                         txouts.push((
 963                                 TxOut {
 964                                         script_pubkey: redeem_script.to_v0_p2wsh(),
 965                                         value: to_broadcaster_value_sat,
 966                                 },
 967                                 None,
 968                         ));
 969                 }
 970
 971                 let mut htlcs = Vec::with_capacity(htlcs_with_aux.len());
 972                 for (htlc, _) in htlcs_with_aux {
 973                         let script = chan_utils::get_htlc_redeemscript(&htlc, &keys);
 974                         let txout = TxOut {
 975                                 script_pubkey: script.to_v0_p2wsh(),
 976                                 value: htlc.amount_msat / 1000,
 977                         };
 978                         txouts.push((txout, Some(htlc)));
 979                 }
 980
 981                 // Sort output in BIP-69 order (amount, scriptPubkey).  Tie-breaks based on HTLC
 982                 // CLTV expiration height.
 983                 sort_outputs(&mut txouts, |a, b| {
 984                         if let &Some(ref a_htlcout) = a {
 985                                 if let &Some(ref b_htlcout) = b {
 986                                         a_htlcout.cltv_expiry.cmp(&b_htlcout.cltv_expiry)
 987                                                 // Note that due to hash collisions, we have to have a fallback comparison
 988                                                 // here for fuzztarget mode (otherwise at least chanmon_fail_consistency
 989                                                 // may fail)!
 990                                                 .then(a_htlcout.payment_hash.0.cmp(&b_htlcout.payment_hash.0))
 991                                 // For non-HTLC outputs, if they're copying our SPK we don't really care if we
 992                                 // close the channel due to mismatches - they're doing something dumb:
 993                                 } else { cmp::Ordering::Equal }
 994                         } else { cmp::Ordering::Equal }
 995                 });
 996
 997                 let mut outputs = Vec::with_capacity(txouts.len());
 998                 for (idx, out) in txouts.drain(..).enumerate() {
 999                         if let Some(htlc) = out.1 {
1000                                 htlc.transaction_output_index = Some(idx as u32);
1001                                 htlcs.push(htlc.clone());
1002                         }
1003                         outputs.push(out.0);
1004                 }
1005                 Ok((outputs, htlcs))
1006         }
1007
1008         fn internal_build_inputs(commitment_number: u64, channel_parameters: &DirectedChannelTransactionParameters) -> (u64, Vec<TxIn>) {
1009                 let broadcaster_pubkeys = channel_parameters.broadcaster_pubkeys();
1010                 let countersignatory_pubkeys = channel_parameters.countersignatory_pubkeys();
1011                 let commitment_transaction_number_obscure_factor = get_commitment_transaction_number_obscure_factor(
1012                         &broadcaster_pubkeys.payment_point,
1013                         &countersignatory_pubkeys.payment_point,
1014                         channel_parameters.is_outbound(),
1015                 );
1016
1017                 let obscured_commitment_transaction_number =
1018                         commitment_transaction_number_obscure_factor ^ (INITIAL_COMMITMENT_NUMBER - commitment_number);
1019
1020                 let txins = {
1021                         let mut ins: Vec<TxIn> = Vec::new();
1022                         ins.push(TxIn {
1023                                 previous_output: channel_parameters.funding_outpoint(),
1024                                 script_sig: Script::new(),
1025                                 sequence: ((0x80 as u32) << 8 * 3)
1026                                         | ((obscured_commitment_transaction_number >> 3 * 8) as u32),
1027                                 witness: Vec::new(),
1028                         });
1029                         ins
1030                 };
1031                 (obscured_commitment_transaction_number, txins)
1032         }
1033
1034         /// The backwards-counting commitment number
1035         pub fn commitment_number(&self) -> u64 {
1036                 self.commitment_number
1037         }
1038
1039         /// The value to be sent to the broadcaster
1040         pub fn to_broadcaster_value_sat(&self) -> u64 {
1041                 self.to_broadcaster_value_sat
1042         }
1043
1044         /// The value to be sent to the counterparty
1045         pub fn to_countersignatory_value_sat(&self) -> u64 {
1046                 self.to_countersignatory_value_sat
1047         }
1048
1049         /// The feerate paid per 1000-weight-unit in this commitment transaction.
1050         pub fn feerate_per_kw(&self) -> u32 {
1051                 self.feerate_per_kw
1052         }
1053
1054         /// The non-dust HTLCs (direction, amt, height expiration, hash, transaction output index)
1055         /// which were included in this commitment transaction in output order.
1056         /// The transaction index is always populated.
1057         ///
1058         /// (C-not exported) as we cannot currently convert Vec references to/from C, though we should
1059         /// expose a less effecient version which creates a Vec of references in the future.
1060         pub fn htlcs(&self) -> &Vec<HTLCOutputInCommitment> {
1061                 &self.htlcs
1062         }
1063
1064         /// Trust our pre-built transaction and derived transaction creation public keys.
1065         ///
1066         /// Applies a wrapper which allows access to these fields.
1067         ///
1068         /// This should only be used if you fully trust the builder of this object.  It should not
1069         ///     be used by an external signer - instead use the verify function.
1070         pub fn trust(&self) -> TrustedCommitmentTransaction {
1071                 TrustedCommitmentTransaction { inner: self }
1072         }
1073
1074         /// Verify our pre-built transaction and derived transaction creation public keys.
1075         ///
1076         /// Applies a wrapper which allows access to these fields.
1077         ///
1078         /// An external validating signer must call this method before signing
1079         /// or using the built transaction.
1080         pub fn verify<T: secp256k1::Signing + secp256k1::Verification>(&self, channel_parameters: &DirectedChannelTransactionParameters, broadcaster_keys: &ChannelPublicKeys, countersignatory_keys: &ChannelPublicKeys, secp_ctx: &Secp256k1<T>) -> Result<TrustedCommitmentTransaction, ()> {
1081                 // This is the only field of the key cache that we trust
1082                 let per_commitment_point = self.keys.per_commitment_point;
1083                 let keys = TxCreationKeys::from_channel_static_keys(&per_commitment_point, broadcaster_keys, countersignatory_keys, secp_ctx).unwrap();
1084                 if keys != self.keys {
1085                         return Err(());
1086                 }
1087                 let tx = self.internal_rebuild_transaction(&keys, channel_parameters)?;
1088                 if self.built.transaction != tx.transaction || self.built.txid != tx.txid {
1089                         return Err(());
1090                 }
1091                 Ok(TrustedCommitmentTransaction { inner: self })
1092         }
1093 }
1094
1095 /// A wrapper on CommitmentTransaction indicating that the derived fields (the built bitcoin
1096 /// transaction and the transaction creation keys) are trusted.
1097 ///
1098 /// See trust() and verify() functions on CommitmentTransaction.
1099 ///
1100 /// This structure implements Deref.
1101 pub struct TrustedCommitmentTransaction<'a> {
1102         inner: &'a CommitmentTransaction,
1103 }
1104
1105 impl<'a> Deref for TrustedCommitmentTransaction<'a> {
1106         type Target = CommitmentTransaction;
1107
1108         fn deref(&self) -> &Self::Target { self.inner }
1109 }
1110
1111 impl<'a> TrustedCommitmentTransaction<'a> {
1112         /// The transaction ID of the built Bitcoin transaction
1113         pub fn txid(&self) -> Txid {
1114                 self.inner.built.txid
1115         }
1116
1117         /// The pre-built Bitcoin commitment transaction
1118         pub fn built_transaction(&self) -> &BuiltCommitmentTransaction {
1119                 &self.inner.built
1120         }
1121
1122         /// The pre-calculated transaction creation public keys.
1123         pub fn keys(&self) -> &TxCreationKeys {
1124                 &self.inner.keys
1125         }
1126
1127         /// Get a signature for each HTLC which was included in the commitment transaction (ie for
1128         /// which HTLCOutputInCommitment::transaction_output_index.is_some()).
1129         ///
1130         /// The returned Vec has one entry for each HTLC, and in the same order.
1131         pub fn get_htlc_sigs<T: secp256k1::Signing>(&self, htlc_base_key: &SecretKey, channel_parameters: &DirectedChannelTransactionParameters, secp_ctx: &Secp256k1<T>) -> Result<Vec<Signature>, ()> {
1132                 let inner = self.inner;
1133                 let keys = &inner.keys;
1134                 let txid = inner.built.txid;
1135                 let mut ret = Vec::with_capacity(inner.htlcs.len());
1136                 let holder_htlc_key = derive_private_key(secp_ctx, &inner.keys.per_commitment_point, htlc_base_key).map_err(|_| ())?;
1137
1138                 for this_htlc in inner.htlcs.iter() {
1139                         assert!(this_htlc.transaction_output_index.is_some());
1140                         let htlc_tx = build_htlc_transaction(&txid, inner.feerate_per_kw, channel_parameters.contest_delay(), &this_htlc, &keys.broadcaster_delayed_payment_key, &keys.revocation_key);
1141
1142                         let htlc_redeemscript = get_htlc_redeemscript_with_explicit_keys(&this_htlc, &keys.broadcaster_htlc_key, &keys.countersignatory_htlc_key, &keys.revocation_key);
1143
1144                         let sighash = hash_to_message!(&bip143::SigHashCache::new(&htlc_tx).signature_hash(0, &htlc_redeemscript, this_htlc.amount_msat / 1000, SigHashType::All)[..]);
1145                         ret.push(secp_ctx.sign(&sighash, &holder_htlc_key));
1146                 }
1147                 Ok(ret)
1148         }
1149
1150         /// Gets a signed HTLC transaction given a preimage (for !htlc.offered) and the holder HTLC transaction signature.
1151         pub(crate) fn get_signed_htlc_tx(&self, channel_parameters: &DirectedChannelTransactionParameters, htlc_index: usize, counterparty_signature: &Signature, signature: &Signature, preimage: &Option<PaymentPreimage>) -> Transaction {
1152                 let inner = self.inner;
1153                 let keys = &inner.keys;
1154                 let txid = inner.built.txid;
1155                 let this_htlc = &inner.htlcs[htlc_index];
1156                 assert!(this_htlc.transaction_output_index.is_some());
1157                 // if we don't have preimage for an HTLC-Success, we can't generate an HTLC transaction.
1158                 if !this_htlc.offered && preimage.is_none() { unreachable!(); }
1159                 // Further, we should never be provided the preimage for an HTLC-Timeout transaction.
1160                 if  this_htlc.offered && preimage.is_some() { unreachable!(); }
1161
1162                 let mut htlc_tx = build_htlc_transaction(&txid, inner.feerate_per_kw, channel_parameters.contest_delay(), &this_htlc, &keys.broadcaster_delayed_payment_key, &keys.revocation_key);
1163
1164                 let htlc_redeemscript = get_htlc_redeemscript_with_explicit_keys(&this_htlc, &keys.broadcaster_htlc_key, &keys.countersignatory_htlc_key, &keys.revocation_key);
1165
1166                 // First push the multisig dummy, note that due to BIP147 (NULLDUMMY) it must be a zero-length element.
1167                 htlc_tx.input[0].witness.push(Vec::new());
1168
1169                 htlc_tx.input[0].witness.push(counterparty_signature.serialize_der().to_vec());
1170                 htlc_tx.input[0].witness.push(signature.serialize_der().to_vec());
1171                 htlc_tx.input[0].witness[1].push(SigHashType::All as u8);
1172                 htlc_tx.input[0].witness[2].push(SigHashType::All as u8);
1173
1174                 if this_htlc.offered {
1175                         // Due to BIP146 (MINIMALIF) this must be a zero-length element to relay.
1176                         htlc_tx.input[0].witness.push(Vec::new());
1177                 } else {
1178                         htlc_tx.input[0].witness.push(preimage.unwrap().0.to_vec());
1179                 }
1180
1181                 htlc_tx.input[0].witness.push(htlc_redeemscript.as_bytes().to_vec());
1182                 htlc_tx
1183         }
1184 }
1185
1186 /// Commitment transaction numbers which appear in the transactions themselves are XOR'd with a
1187 /// shared secret first. This prevents on-chain observers from discovering how many commitment
1188 /// transactions occurred in a channel before it was closed.
1189 ///
1190 /// This function gets the shared secret from relevant channel public keys and can be used to
1191 /// "decrypt" the commitment transaction number given a commitment transaction on-chain.
1192 pub fn get_commitment_transaction_number_obscure_factor(
1193         broadcaster_payment_basepoint: &PublicKey,
1194         countersignatory_payment_basepoint: &PublicKey,
1195         outbound_from_broadcaster: bool,
1196 ) -> u64 {
1197         let mut sha = Sha256::engine();
1198
1199         if outbound_from_broadcaster {
1200                 sha.input(&broadcaster_payment_basepoint.serialize());
1201                 sha.input(&countersignatory_payment_basepoint.serialize());
1202         } else {
1203                 sha.input(&countersignatory_payment_basepoint.serialize());
1204                 sha.input(&broadcaster_payment_basepoint.serialize());
1205         }
1206         let res = Sha256::from_engine(sha).into_inner();
1207
1208         ((res[26] as u64) << 5 * 8)
1209                 | ((res[27] as u64) << 4 * 8)
1210                 | ((res[28] as u64) << 3 * 8)
1211                 | ((res[29] as u64) << 2 * 8)
1212                 | ((res[30] as u64) << 1 * 8)
1213                 | ((res[31] as u64) << 0 * 8)
1214 }
1215
1216 fn script_for_p2wpkh(key: &PublicKey) -> Script {
1217         Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0)
1218                 .push_slice(&WPubkeyHash::hash(&key.serialize())[..])
1219                 .into_script()
1220 }
1221
1222 #[cfg(test)]
1223 mod tests {
1224         use super::CounterpartyCommitmentSecrets;
1225         use hex;
1226         use prelude::*;
1227
1228         #[test]
1229         fn test_per_commitment_storage() {
1230                 // Test vectors from BOLT 3:
1231                 let mut secrets: Vec<[u8; 32]> = Vec::new();
1232                 let mut monitor;
1233
1234                 macro_rules! test_secrets {
1235                         () => {
1236                                 let mut idx = 281474976710655;
1237                                 for secret in secrets.iter() {
1238                                         assert_eq!(monitor.get_secret(idx).unwrap(), *secret);
1239                                         idx -= 1;
1240                                 }
1241                                 assert_eq!(monitor.get_min_seen_secret(), idx + 1);
1242                                 assert!(monitor.get_secret(idx).is_none());
1243                         };
1244                 }
1245
1246                 {
1247                         // insert_secret correct sequence
1248                         monitor = CounterpartyCommitmentSecrets::new();
1249                         secrets.clear();
1250
1251                         secrets.push([0; 32]);
1252                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1253                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1254                         test_secrets!();
1255
1256                         secrets.push([0; 32]);
1257                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1258                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1259                         test_secrets!();
1260
1261                         secrets.push([0; 32]);
1262                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1263                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1264                         test_secrets!();
1265
1266                         secrets.push([0; 32]);
1267                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1268                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
1269                         test_secrets!();
1270
1271                         secrets.push([0; 32]);
1272                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
1273                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
1274                         test_secrets!();
1275
1276                         secrets.push([0; 32]);
1277                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
1278                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
1279                         test_secrets!();
1280
1281                         secrets.push([0; 32]);
1282                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
1283                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
1284                         test_secrets!();
1285
1286                         secrets.push([0; 32]);
1287                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
1288                         monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap();
1289                         test_secrets!();
1290                 }
1291
1292                 {
1293                         // insert_secret #1 incorrect
1294                         monitor = CounterpartyCommitmentSecrets::new();
1295                         secrets.clear();
1296
1297                         secrets.push([0; 32]);
1298                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
1299                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1300                         test_secrets!();
1301
1302                         secrets.push([0; 32]);
1303                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1304                         assert!(monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).is_err());
1305                 }
1306
1307                 {
1308                         // insert_secret #2 incorrect (#1 derived from incorrect)
1309                         monitor = CounterpartyCommitmentSecrets::new();
1310                         secrets.clear();
1311
1312                         secrets.push([0; 32]);
1313                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
1314                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1315                         test_secrets!();
1316
1317                         secrets.push([0; 32]);
1318                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("dddc3a8d14fddf2b68fa8c7fbad2748274937479dd0f8930d5ebb4ab6bd866a3").unwrap());
1319                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1320                         test_secrets!();
1321
1322                         secrets.push([0; 32]);
1323                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1324                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1325                         test_secrets!();
1326
1327                         secrets.push([0; 32]);
1328                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1329                         assert!(monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).is_err());
1330                 }
1331
1332                 {
1333                         // insert_secret #3 incorrect
1334                         monitor = CounterpartyCommitmentSecrets::new();
1335                         secrets.clear();
1336
1337                         secrets.push([0; 32]);
1338                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1339                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1340                         test_secrets!();
1341
1342                         secrets.push([0; 32]);
1343                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1344                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1345                         test_secrets!();
1346
1347                         secrets.push([0; 32]);
1348                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c51a18b13e8527e579ec56365482c62f180b7d5760b46e9477dae59e87ed423a").unwrap());
1349                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1350                         test_secrets!();
1351
1352                         secrets.push([0; 32]);
1353                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1354                         assert!(monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).is_err());
1355                 }
1356
1357                 {
1358                         // insert_secret #4 incorrect (1,2,3 derived from incorrect)
1359                         monitor = CounterpartyCommitmentSecrets::new();
1360                         secrets.clear();
1361
1362                         secrets.push([0; 32]);
1363                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
1364                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1365                         test_secrets!();
1366
1367                         secrets.push([0; 32]);
1368                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("dddc3a8d14fddf2b68fa8c7fbad2748274937479dd0f8930d5ebb4ab6bd866a3").unwrap());
1369                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1370                         test_secrets!();
1371
1372                         secrets.push([0; 32]);
1373                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c51a18b13e8527e579ec56365482c62f180b7d5760b46e9477dae59e87ed423a").unwrap());
1374                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1375                         test_secrets!();
1376
1377                         secrets.push([0; 32]);
1378                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("ba65d7b0ef55a3ba300d4e87af29868f394f8f138d78a7011669c79b37b936f4").unwrap());
1379                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
1380                         test_secrets!();
1381
1382                         secrets.push([0; 32]);
1383                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
1384                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
1385                         test_secrets!();
1386
1387                         secrets.push([0; 32]);
1388                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
1389                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
1390                         test_secrets!();
1391
1392                         secrets.push([0; 32]);
1393                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
1394                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
1395                         test_secrets!();
1396
1397                         secrets.push([0; 32]);
1398                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
1399                         assert!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).is_err());
1400                 }
1401
1402                 {
1403                         // insert_secret #5 incorrect
1404                         monitor = CounterpartyCommitmentSecrets::new();
1405                         secrets.clear();
1406
1407                         secrets.push([0; 32]);
1408                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1409                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1410                         test_secrets!();
1411
1412                         secrets.push([0; 32]);
1413                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1414                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1415                         test_secrets!();
1416
1417                         secrets.push([0; 32]);
1418                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1419                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1420                         test_secrets!();
1421
1422                         secrets.push([0; 32]);
1423                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1424                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
1425                         test_secrets!();
1426
1427                         secrets.push([0; 32]);
1428                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("631373ad5f9ef654bb3dade742d09504c567edd24320d2fcd68e3cc47e2ff6a6").unwrap());
1429                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
1430                         test_secrets!();
1431
1432                         secrets.push([0; 32]);
1433                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
1434                         assert!(monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).is_err());
1435                 }
1436
1437                 {
1438                         // insert_secret #6 incorrect (5 derived from incorrect)
1439                         monitor = CounterpartyCommitmentSecrets::new();
1440                         secrets.clear();
1441
1442                         secrets.push([0; 32]);
1443                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1444                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1445                         test_secrets!();
1446
1447                         secrets.push([0; 32]);
1448                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1449                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1450                         test_secrets!();
1451
1452                         secrets.push([0; 32]);
1453                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1454                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1455                         test_secrets!();
1456
1457                         secrets.push([0; 32]);
1458                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1459                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
1460                         test_secrets!();
1461
1462                         secrets.push([0; 32]);
1463                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("631373ad5f9ef654bb3dade742d09504c567edd24320d2fcd68e3cc47e2ff6a6").unwrap());
1464                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
1465                         test_secrets!();
1466
1467                         secrets.push([0; 32]);
1468                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("b7e76a83668bde38b373970155c868a653304308f9896692f904a23731224bb1").unwrap());
1469                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
1470                         test_secrets!();
1471
1472                         secrets.push([0; 32]);
1473                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
1474                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
1475                         test_secrets!();
1476
1477                         secrets.push([0; 32]);
1478                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
1479                         assert!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).is_err());
1480                 }
1481
1482                 {
1483                         // insert_secret #7 incorrect
1484                         monitor = CounterpartyCommitmentSecrets::new();
1485                         secrets.clear();
1486
1487                         secrets.push([0; 32]);
1488                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1489                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1490                         test_secrets!();
1491
1492                         secrets.push([0; 32]);
1493                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1494                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1495                         test_secrets!();
1496
1497                         secrets.push([0; 32]);
1498                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1499                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1500                         test_secrets!();
1501
1502                         secrets.push([0; 32]);
1503                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1504                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
1505                         test_secrets!();
1506
1507                         secrets.push([0; 32]);
1508                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
1509                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
1510                         test_secrets!();
1511
1512                         secrets.push([0; 32]);
1513                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
1514                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
1515                         test_secrets!();
1516
1517                         secrets.push([0; 32]);
1518                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("e7971de736e01da8ed58b94c2fc216cb1dca9e326f3a96e7194fe8ea8af6c0a3").unwrap());
1519                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
1520                         test_secrets!();
1521
1522                         secrets.push([0; 32]);
1523                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
1524                         assert!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).is_err());
1525                 }
1526
1527                 {
1528                         // insert_secret #8 incorrect
1529                         monitor = CounterpartyCommitmentSecrets::new();
1530                         secrets.clear();
1531
1532                         secrets.push([0; 32]);
1533                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1534                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1535                         test_secrets!();
1536
1537                         secrets.push([0; 32]);
1538                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1539                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1540                         test_secrets!();
1541
1542                         secrets.push([0; 32]);
1543                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1544                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1545                         test_secrets!();
1546
1547                         secrets.push([0; 32]);
1548                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1549                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
1550                         test_secrets!();
1551
1552                         secrets.push([0; 32]);
1553                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
1554                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
1555                         test_secrets!();
1556
1557                         secrets.push([0; 32]);
1558                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
1559                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
1560                         test_secrets!();
1561
1562                         secrets.push([0; 32]);
1563                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
1564                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
1565                         test_secrets!();
1566
1567                         secrets.push([0; 32]);
1568                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a7efbc61aac46d34f77778bac22c8a20c6a46ca460addc49009bda875ec88fa4").unwrap());
1569                         assert!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).is_err());
1570                 }
1571         }
1572 }