_ 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, MAX_BUF_SIZE};
  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 core::cmp;
  35 use ln::chan_utils;
  36 use util::transaction_utils::sort_outputs;
  37 use ln::channel::INITIAL_COMMITMENT_NUMBER;
  38 use std::io::Read;
  39 use core::ops::Deref;
  40 use chain;
  41
  42 // Maximum size of a serialized HTLCOutputInCommitment
  43 pub(crate) const HTLC_OUTPUT_IN_COMMITMENT_SIZE: usize = 1 + 8 + 4 + 32 + 5;
  44
  45 pub(crate) const MAX_HTLCS: u16 = 483;
  46
  47 // This checks that the buffer size is greater than the maximum possible size for serialized HTLCS
  48 const _EXCESS_BUFFER_SIZE: usize = MAX_BUF_SIZE - MAX_HTLCS as usize * HTLC_OUTPUT_IN_COMMITMENT_SIZE;
  49
  50 pub(super) const HTLC_SUCCESS_TX_WEIGHT: u64 = 703;
  51 pub(super) const HTLC_TIMEOUT_TX_WEIGHT: u64 = 663;
  52
  53 #[derive(PartialEq)]
  54 pub(crate) enum HTLCType {
  55         AcceptedHTLC,
  56         OfferedHTLC
  57 }
  58
  59 impl HTLCType {
  60         /// Check if a given tx witnessScript len matchs one of a pre-signed HTLC
  61         pub(crate) fn scriptlen_to_htlctype(witness_script_len: usize) ->  Option<HTLCType> {
  62                 if witness_script_len == 133 {
  63                         Some(HTLCType::OfferedHTLC)
  64                 } else if witness_script_len >= 136 && witness_script_len <= 139 {
  65                         Some(HTLCType::AcceptedHTLC)
  66                 } else {
  67                         None
  68                 }
  69         }
  70 }
  71
  72 // Various functions for key derivation and transaction creation for use within channels. Primarily
  73 // used in Channel and ChannelMonitor.
  74
  75 /// Build the commitment secret from the seed and the commitment number
  76 pub fn build_commitment_secret(commitment_seed: &[u8; 32], idx: u64) -> [u8; 32] {
  77         let mut res: [u8; 32] = commitment_seed.clone();
  78         for i in 0..48 {
  79                 let bitpos = 47 - i;
  80                 if idx & (1 << bitpos) == (1 << bitpos) {
  81                         res[bitpos / 8] ^= 1 << (bitpos & 7);
  82                         res = Sha256::hash(&res).into_inner();
  83                 }
  84         }
  85         res
  86 }
  87
  88 /// Implements the per-commitment secret storage scheme from
  89 /// [BOLT 3](https://github.com/lightningnetwork/lightning-rfc/blob/dcbf8583976df087c79c3ce0b535311212e6812d/03-transactions.md#efficient-per-commitment-secret-storage).
  90 ///
  91 /// Allows us to keep track of all of the revocation secrets of counterarties in just 50*32 bytes
  92 /// or so.
  93 #[derive(Clone)]
  94 pub(crate) struct CounterpartyCommitmentSecrets {
  95         old_secrets: [([u8; 32], u64); 49],
  96 }
  97
  98 impl PartialEq for CounterpartyCommitmentSecrets {
  99         fn eq(&self, other: &Self) -> bool {
 100                 for (&(ref secret, ref idx), &(ref o_secret, ref o_idx)) in self.old_secrets.iter().zip(other.old_secrets.iter()) {
 101                         if secret != o_secret || idx != o_idx {
 102                                 return false
 103                         }
 104                 }
 105                 true
 106         }
 107 }
 108
 109 impl CounterpartyCommitmentSecrets {
 110         pub(crate) fn new() -> Self {
 111                 Self { old_secrets: [([0; 32], 1 << 48); 49], }
 112         }
 113
 114         #[inline]
 115         fn place_secret(idx: u64) -> u8 {
 116                 for i in 0..48 {
 117                         if idx & (1 << i) == (1 << i) {
 118                                 return i
 119                         }
 120                 }
 121                 48
 122         }
 123
 124         pub(crate) fn get_min_seen_secret(&self) -> u64 {
 125                 //TODO This can be optimized?
 126                 let mut min = 1 << 48;
 127                 for &(_, idx) in self.old_secrets.iter() {
 128                         if idx < min {
 129                                 min = idx;
 130                         }
 131                 }
 132                 min
 133         }
 134
 135         #[inline]
 136         fn derive_secret(secret: [u8; 32], bits: u8, idx: u64) -> [u8; 32] {
 137                 let mut res: [u8; 32] = secret;
 138                 for i in 0..bits {
 139                         let bitpos = bits - 1 - i;
 140                         if idx & (1 << bitpos) == (1 << bitpos) {
 141                                 res[(bitpos / 8) as usize] ^= 1 << (bitpos & 7);
 142                                 res = Sha256::hash(&res).into_inner();
 143                         }
 144                 }
 145                 res
 146         }
 147
 148         pub(crate) fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), ()> {
 149                 let pos = Self::place_secret(idx);
 150                 for i in 0..pos {
 151                         let (old_secret, old_idx) = self.old_secrets[i as usize];
 152                         if Self::derive_secret(secret, pos, old_idx) != old_secret {
 153                                 return Err(());
 154                         }
 155                 }
 156                 if self.get_min_seen_secret() <= idx {
 157                         return Ok(());
 158                 }
 159                 self.old_secrets[pos as usize] = (secret, idx);
 160                 Ok(())
 161         }
 162
 163         /// Can only fail if idx is < get_min_seen_secret
 164         pub(crate) fn get_secret(&self, idx: u64) -> Option<[u8; 32]> {
 165                 for i in 0..self.old_secrets.len() {
 166                         if (idx & (!((1 << i) - 1))) == self.old_secrets[i].1 {
 167                                 return Some(Self::derive_secret(self.old_secrets[i].0, i as u8, idx))
 168                         }
 169                 }
 170                 assert!(idx < self.get_min_seen_secret());
 171                 None
 172         }
 173 }
 174
 175 impl Writeable for CounterpartyCommitmentSecrets {
 176         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
 177                 for &(ref secret, ref idx) in self.old_secrets.iter() {
 178                         writer.write_all(secret)?;
 179                         writer.write_all(&byte_utils::be64_to_array(*idx))?;
 180                 }
 181                 write_tlv_fields!(writer, {}, {});
 182                 Ok(())
 183         }
 184 }
 185 impl Readable for CounterpartyCommitmentSecrets {
 186         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
 187                 let mut old_secrets = [([0; 32], 1 << 48); 49];
 188                 for &mut (ref mut secret, ref mut idx) in old_secrets.iter_mut() {
 189                         *secret = Readable::read(reader)?;
 190                         *idx = Readable::read(reader)?;
 191                 }
 192                 read_tlv_fields!(reader, {}, {});
 193                 Ok(Self { old_secrets })
 194         }
 195 }
 196
 197 /// Derives a per-commitment-transaction private key (eg an htlc key or delayed_payment key)
 198 /// from the base secret and the per_commitment_point.
 199 ///
 200 /// Note that this is infallible iff we trust that at least one of the two input keys are randomly
 201 /// generated (ie our own).
 202 pub fn derive_private_key<T: secp256k1::Signing>(secp_ctx: &Secp256k1<T>, per_commitment_point: &PublicKey, base_secret: &SecretKey) -> Result<SecretKey, SecpError> {
 203         let mut sha = Sha256::engine();
 204         sha.input(&per_commitment_point.serialize());
 205         sha.input(&PublicKey::from_secret_key(&secp_ctx, &base_secret).serialize());
 206         let res = Sha256::from_engine(sha).into_inner();
 207
 208         let mut key = base_secret.clone();
 209         key.add_assign(&res)?;
 210         Ok(key)
 211 }
 212
 213 /// Derives a per-commitment-transaction public key (eg an htlc key or a delayed_payment key)
 214 /// from the base point and the per_commitment_key. This is the public equivalent of
 215 /// derive_private_key - using only public keys to derive a public key instead of private keys.
 216 ///
 217 /// Note that this is infallible iff we trust that at least one of the two input keys are randomly
 218 /// generated (ie our own).
 219 pub fn derive_public_key<T: secp256k1::Signing>(secp_ctx: &Secp256k1<T>, per_commitment_point: &PublicKey, base_point: &PublicKey) -> Result<PublicKey, SecpError> {
 220         let mut sha = Sha256::engine();
 221         sha.input(&per_commitment_point.serialize());
 222         sha.input(&base_point.serialize());
 223         let res = Sha256::from_engine(sha).into_inner();
 224
 225         let hashkey = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&res)?);
 226         base_point.combine(&hashkey)
 227 }
 228
 229 /// Derives a per-commitment-transaction revocation key from its constituent parts.
 230 ///
 231 /// Only the cheating participant owns a valid witness to propagate a revoked
 232 /// commitment transaction, thus per_commitment_secret always come from cheater
 233 /// and revocation_base_secret always come from punisher, which is the broadcaster
 234 /// of the transaction spending with this key knowledge.
 235 ///
 236 /// Note that this is infallible iff we trust that at least one of the two input keys are randomly
 237 /// generated (ie our own).
 238 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> {
 239         let countersignatory_revocation_base_point = PublicKey::from_secret_key(&secp_ctx, &countersignatory_revocation_base_secret);
 240         let per_commitment_point = PublicKey::from_secret_key(&secp_ctx, &per_commitment_secret);
 241
 242         let rev_append_commit_hash_key = {
 243                 let mut sha = Sha256::engine();
 244                 sha.input(&countersignatory_revocation_base_point.serialize());
 245                 sha.input(&per_commitment_point.serialize());
 246
 247                 Sha256::from_engine(sha).into_inner()
 248         };
 249         let commit_append_rev_hash_key = {
 250                 let mut sha = Sha256::engine();
 251                 sha.input(&per_commitment_point.serialize());
 252                 sha.input(&countersignatory_revocation_base_point.serialize());
 253
 254                 Sha256::from_engine(sha).into_inner()
 255         };
 256
 257         let mut countersignatory_contrib = countersignatory_revocation_base_secret.clone();
 258         countersignatory_contrib.mul_assign(&rev_append_commit_hash_key)?;
 259         let mut broadcaster_contrib = per_commitment_secret.clone();
 260         broadcaster_contrib.mul_assign(&commit_append_rev_hash_key)?;
 261         countersignatory_contrib.add_assign(&broadcaster_contrib[..])?;
 262         Ok(countersignatory_contrib)
 263 }
 264
 265 /// Derives a per-commitment-transaction revocation public key from its constituent parts. This is
 266 /// the public equivalend of derive_private_revocation_key - using only public keys to derive a
 267 /// public key instead of private keys.
 268 ///
 269 /// Only the cheating participant owns a valid witness to propagate a revoked
 270 /// commitment transaction, thus per_commitment_point always come from cheater
 271 /// and revocation_base_point always come from punisher, which is the broadcaster
 272 /// of the transaction spending with this key knowledge.
 273 ///
 274 /// Note that this is infallible iff we trust that at least one of the two input keys are randomly
 275 /// generated (ie our own).
 276 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> {
 277         let rev_append_commit_hash_key = {
 278                 let mut sha = Sha256::engine();
 279                 sha.input(&countersignatory_revocation_base_point.serialize());
 280                 sha.input(&per_commitment_point.serialize());
 281
 282                 Sha256::from_engine(sha).into_inner()
 283         };
 284         let commit_append_rev_hash_key = {
 285                 let mut sha = Sha256::engine();
 286                 sha.input(&per_commitment_point.serialize());
 287                 sha.input(&countersignatory_revocation_base_point.serialize());
 288
 289                 Sha256::from_engine(sha).into_inner()
 290         };
 291
 292         let mut countersignatory_contrib = countersignatory_revocation_base_point.clone();
 293         countersignatory_contrib.mul_assign(&secp_ctx, &rev_append_commit_hash_key)?;
 294         let mut broadcaster_contrib = per_commitment_point.clone();
 295         broadcaster_contrib.mul_assign(&secp_ctx, &commit_append_rev_hash_key)?;
 296         countersignatory_contrib.combine(&broadcaster_contrib)
 297 }
 298
 299 /// The set of public keys which are used in the creation of one commitment transaction.
 300 /// These are derived from the channel base keys and per-commitment data.
 301 ///
 302 /// A broadcaster key is provided from potential broadcaster of the computed transaction.
 303 /// A countersignatory key is coming from a protocol participant unable to broadcast the
 304 /// transaction.
 305 ///
 306 /// These keys are assumed to be good, either because the code derived them from
 307 /// channel basepoints via the new function, or they were obtained via
 308 /// CommitmentTransaction.trust().keys() because we trusted the source of the
 309 /// pre-calculated keys.
 310 #[derive(PartialEq, Clone)]
 311 pub struct TxCreationKeys {
 312         /// The broadcaster's per-commitment public key which was used to derive the other keys.
 313         pub per_commitment_point: PublicKey,
 314         /// The revocation key which is used to allow the broadcaster of the commitment
 315         /// transaction to provide their counterparty the ability to punish them if they broadcast
 316         /// an old state.
 317         pub revocation_key: PublicKey,
 318         /// Broadcaster's HTLC Key
 319         pub broadcaster_htlc_key: PublicKey,
 320         /// Countersignatory's HTLC Key
 321         pub countersignatory_htlc_key: PublicKey,
 322         /// Broadcaster's Payment Key (which isn't allowed to be spent from for some delay)
 323         pub broadcaster_delayed_payment_key: PublicKey,
 324 }
 325
 326 impl_writeable_tlv_based!(TxCreationKeys, {
 327         (0, per_commitment_point),
 328         (2, revocation_key),
 329         (4, broadcaster_htlc_key),
 330         (6, countersignatory_htlc_key),
 331         (8, broadcaster_delayed_payment_key),
 332 }, {}, {});
 333
 334 /// One counterparty's public keys which do not change over the life of a channel.
 335 #[derive(Clone, PartialEq)]
 336 pub struct ChannelPublicKeys {
 337         /// The public key which is used to sign all commitment transactions, as it appears in the
 338         /// on-chain channel lock-in 2-of-2 multisig output.
 339         pub funding_pubkey: PublicKey,
 340         /// The base point which is used (with derive_public_revocation_key) to derive per-commitment
 341         /// revocation keys. This is combined with the per-commitment-secret generated by the
 342         /// counterparty to create a secret which the counterparty can reveal to revoke previous
 343         /// states.
 344         pub revocation_basepoint: PublicKey,
 345         /// The public key on which the non-broadcaster (ie the countersignatory) receives an immediately
 346         /// spendable primary channel balance on the broadcaster's commitment transaction. This key is
 347         /// static across every commitment transaction.
 348         pub payment_point: PublicKey,
 349         /// The base point which is used (with derive_public_key) to derive a per-commitment payment
 350         /// public key which receives non-HTLC-encumbered funds which are only available for spending
 351         /// after some delay (or can be claimed via the revocation path).
 352         pub delayed_payment_basepoint: PublicKey,
 353         /// The base point which is used (with derive_public_key) to derive a per-commitment public key
 354         /// which is used to encumber HTLC-in-flight outputs.
 355         pub htlc_basepoint: PublicKey,
 356 }
 357
 358 impl_writeable_tlv_based!(ChannelPublicKeys, {
 359         (0, funding_pubkey),
 360         (2, revocation_basepoint),
 361         (4, payment_point),
 362         (6, delayed_payment_basepoint),
 363         (8, htlc_basepoint),
 364 }, {}, {});
 365
 366 impl TxCreationKeys {
 367         /// Create per-state keys from channel base points and the per-commitment point.
 368         /// Key set is asymmetric and can't be used as part of counter-signatory set of transactions.
 369         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> {
 370                 Ok(TxCreationKeys {
 371                         per_commitment_point: per_commitment_point.clone(),
 372                         revocation_key: derive_public_revocation_key(&secp_ctx, &per_commitment_point, &countersignatory_revocation_base)?,
 373                         broadcaster_htlc_key: derive_public_key(&secp_ctx, &per_commitment_point, &broadcaster_htlc_base)?,
 374                         countersignatory_htlc_key: derive_public_key(&secp_ctx, &per_commitment_point, &countersignatory_htlc_base)?,
 375                         broadcaster_delayed_payment_key: derive_public_key(&secp_ctx, &per_commitment_point, &broadcaster_delayed_payment_base)?,
 376                 })
 377         }
 378
 379         /// Generate per-state keys from channel static keys.
 380         /// Key set is asymmetric and can't be used as part of counter-signatory set of transactions.
 381         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> {
 382                 TxCreationKeys::derive_new(
 383                         &secp_ctx,
 384                         &per_commitment_point,
 385                         &broadcaster_keys.delayed_payment_basepoint,
 386                         &broadcaster_keys.htlc_basepoint,
 387                         &countersignatory_keys.revocation_basepoint,
 388                         &countersignatory_keys.htlc_basepoint,
 389                 )
 390         }
 391 }
 392
 393 /// The maximum length of a script returned by get_revokeable_redeemscript.
 394 // Calculated as 6 bytes of opcodes, 1 byte push plus 2 bytes for contest_delay, and two public
 395 // keys of 33 bytes (+ 1 push).
 396 pub const REVOKEABLE_REDEEMSCRIPT_MAX_LENGTH: usize = 6 + 3 + 34*2;
 397
 398 /// A script either spendable by the revocation
 399 /// key or the broadcaster_delayed_payment_key and satisfying the relative-locktime OP_CSV constrain.
 400 /// Encumbering a `to_holder` output on a commitment transaction or 2nd-stage HTLC transactions.
 401 pub fn get_revokeable_redeemscript(revocation_key: &PublicKey, contest_delay: u16, broadcaster_delayed_payment_key: &PublicKey) -> Script {
 402         let res = Builder::new().push_opcode(opcodes::all::OP_IF)
 403                       .push_slice(&revocation_key.serialize())
 404                       .push_opcode(opcodes::all::OP_ELSE)
 405                       .push_int(contest_delay as i64)
 406                       .push_opcode(opcodes::all::OP_CSV)
 407                       .push_opcode(opcodes::all::OP_DROP)
 408                       .push_slice(&broadcaster_delayed_payment_key.serialize())
 409                       .push_opcode(opcodes::all::OP_ENDIF)
 410                       .push_opcode(opcodes::all::OP_CHECKSIG)
 411                       .into_script();
 412         debug_assert!(res.len() <= REVOKEABLE_REDEEMSCRIPT_MAX_LENGTH);
 413         res
 414 }
 415
 416 #[derive(Clone, PartialEq)]
 417 /// Information about an HTLC as it appears in a commitment transaction
 418 pub struct HTLCOutputInCommitment {
 419         /// Whether the HTLC was "offered" (ie outbound in relation to this commitment transaction).
 420         /// Note that this is not the same as whether it is ountbound *from us*. To determine that you
 421         /// need to compare this value to whether the commitment transaction in question is that of
 422         /// the counterparty or our own.
 423         pub offered: bool,
 424         /// The value, in msat, of the HTLC. The value as it appears in the commitment transaction is
 425         /// this divided by 1000.
 426         pub amount_msat: u64,
 427         /// The CLTV lock-time at which this HTLC expires.
 428         pub cltv_expiry: u32,
 429         /// The hash of the preimage which unlocks this HTLC.
 430         pub payment_hash: PaymentHash,
 431         /// The position within the commitment transactions' outputs. This may be None if the value is
 432         /// below the dust limit (in which case no output appears in the commitment transaction and the
 433         /// value is spent to additional transaction fees).
 434         pub transaction_output_index: Option<u32>,
 435 }
 436
 437 impl_writeable_tlv_based!(HTLCOutputInCommitment, {
 438         (0, offered),
 439         (2, amount_msat),
 440         (4, cltv_expiry),
 441         (6, payment_hash),
 442 }, {
 443         (8, transaction_output_index)
 444 }, {});
 445
 446 #[inline]
 447 pub(crate) fn get_htlc_redeemscript_with_explicit_keys(htlc: &HTLCOutputInCommitment, broadcaster_htlc_key: &PublicKey, countersignatory_htlc_key: &PublicKey, revocation_key: &PublicKey) -> Script {
 448         let payment_hash160 = Ripemd160::hash(&htlc.payment_hash.0[..]).into_inner();
 449         if htlc.offered {
 450                 Builder::new().push_opcode(opcodes::all::OP_DUP)
 451                               .push_opcode(opcodes::all::OP_HASH160)
 452                               .push_slice(&PubkeyHash::hash(&revocation_key.serialize())[..])
 453                               .push_opcode(opcodes::all::OP_EQUAL)
 454                               .push_opcode(opcodes::all::OP_IF)
 455                               .push_opcode(opcodes::all::OP_CHECKSIG)
 456                               .push_opcode(opcodes::all::OP_ELSE)
 457                               .push_slice(&countersignatory_htlc_key.serialize()[..])
 458                               .push_opcode(opcodes::all::OP_SWAP)
 459                               .push_opcode(opcodes::all::OP_SIZE)
 460                               .push_int(32)
 461                               .push_opcode(opcodes::all::OP_EQUAL)
 462                               .push_opcode(opcodes::all::OP_NOTIF)
 463                               .push_opcode(opcodes::all::OP_DROP)
 464                               .push_int(2)
 465                               .push_opcode(opcodes::all::OP_SWAP)
 466                               .push_slice(&broadcaster_htlc_key.serialize()[..])
 467                               .push_int(2)
 468                               .push_opcode(opcodes::all::OP_CHECKMULTISIG)
 469                               .push_opcode(opcodes::all::OP_ELSE)
 470                               .push_opcode(opcodes::all::OP_HASH160)
 471                               .push_slice(&payment_hash160)
 472                               .push_opcode(opcodes::all::OP_EQUALVERIFY)
 473                               .push_opcode(opcodes::all::OP_CHECKSIG)
 474                               .push_opcode(opcodes::all::OP_ENDIF)
 475                               .push_opcode(opcodes::all::OP_ENDIF)
 476                               .into_script()
 477         } else {
 478                 Builder::new().push_opcode(opcodes::all::OP_DUP)
 479                               .push_opcode(opcodes::all::OP_HASH160)
 480                               .push_slice(&PubkeyHash::hash(&revocation_key.serialize())[..])
 481                               .push_opcode(opcodes::all::OP_EQUAL)
 482                               .push_opcode(opcodes::all::OP_IF)
 483                               .push_opcode(opcodes::all::OP_CHECKSIG)
 484                               .push_opcode(opcodes::all::OP_ELSE)
 485                               .push_slice(&countersignatory_htlc_key.serialize()[..])
 486                               .push_opcode(opcodes::all::OP_SWAP)
 487                               .push_opcode(opcodes::all::OP_SIZE)
 488                               .push_int(32)
 489                               .push_opcode(opcodes::all::OP_EQUAL)
 490                               .push_opcode(opcodes::all::OP_IF)
 491                               .push_opcode(opcodes::all::OP_HASH160)
 492                               .push_slice(&payment_hash160)
 493                               .push_opcode(opcodes::all::OP_EQUALVERIFY)
 494                               .push_int(2)
 495                               .push_opcode(opcodes::all::OP_SWAP)
 496                               .push_slice(&broadcaster_htlc_key.serialize()[..])
 497                               .push_int(2)
 498                               .push_opcode(opcodes::all::OP_CHECKMULTISIG)
 499                               .push_opcode(opcodes::all::OP_ELSE)
 500                               .push_opcode(opcodes::all::OP_DROP)
 501                               .push_int(htlc.cltv_expiry as i64)
 502                               .push_opcode(opcodes::all::OP_CLTV)
 503                               .push_opcode(opcodes::all::OP_DROP)
 504                               .push_opcode(opcodes::all::OP_CHECKSIG)
 505                               .push_opcode(opcodes::all::OP_ENDIF)
 506                               .push_opcode(opcodes::all::OP_ENDIF)
 507                               .into_script()
 508         }
 509 }
 510
 511 /// Gets the witness redeemscript for an HTLC output in a commitment transaction. Note that htlc
 512 /// does not need to have its previous_output_index filled.
 513 #[inline]
 514 pub fn get_htlc_redeemscript(htlc: &HTLCOutputInCommitment, keys: &TxCreationKeys) -> Script {
 515         get_htlc_redeemscript_with_explicit_keys(htlc, &keys.broadcaster_htlc_key, &keys.countersignatory_htlc_key, &keys.revocation_key)
 516 }
 517
 518 /// Gets the redeemscript for a funding output from the two funding public keys.
 519 /// Note that the order of funding public keys does not matter.
 520 pub fn make_funding_redeemscript(broadcaster: &PublicKey, countersignatory: &PublicKey) -> Script {
 521         let broadcaster_funding_key = broadcaster.serialize();
 522         let countersignatory_funding_key = countersignatory.serialize();
 523
 524         let builder = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2);
 525         if broadcaster_funding_key[..] < countersignatory_funding_key[..] {
 526                 builder.push_slice(&broadcaster_funding_key)
 527                         .push_slice(&countersignatory_funding_key)
 528         } else {
 529                 builder.push_slice(&countersignatory_funding_key)
 530                         .push_slice(&broadcaster_funding_key)
 531         }.push_opcode(opcodes::all::OP_PUSHNUM_2).push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script()
 532 }
 533
 534 /// panics if htlc.transaction_output_index.is_none()!
 535 pub fn build_htlc_transaction(prev_hash: &Txid, feerate_per_kw: u32, contest_delay: u16, htlc: &HTLCOutputInCommitment, broadcaster_delayed_payment_key: &PublicKey, revocation_key: &PublicKey) -> Transaction {
 536         let mut txins: Vec<TxIn> = Vec::new();
 537         txins.push(TxIn {
 538                 previous_output: OutPoint {
 539                         txid: prev_hash.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 /// (C-not exported) as users never need to call this directly
 869 impl Writeable for Vec<HTLCOutputInCommitment> {
 870         #[inline]
 871         fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
 872                 (self.len() as u16).write(w)?;
 873                 for e in self.iter() {
 874                         e.write(w)?;
 875                 }
 876                 Ok(())
 877         }
 878 }
 879
 880 /// (C-not exported) as users never need to call this directly
 881 impl Readable for Vec<HTLCOutputInCommitment> {
 882         #[inline]
 883         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 884                 let len: u16 = Readable::read(r)?;
 885                 let byte_size = (len as usize)
 886                         .checked_mul(HTLC_OUTPUT_IN_COMMITMENT_SIZE)
 887                         .ok_or(DecodeError::BadLengthDescriptor)?;
 888                 if byte_size > MAX_BUF_SIZE {
 889                         return Err(DecodeError::BadLengthDescriptor);
 890                 }
 891                 let mut ret = Vec::with_capacity(len as usize);
 892                 for _ in 0..len { ret.push(HTLCOutputInCommitment::read(r)?); }
 893                 Ok(ret)
 894         }
 895 }
 896
 897 impl_writeable_tlv_based!(CommitmentTransaction, {
 898         (0, commitment_number),
 899         (2, to_broadcaster_value_sat),
 900         (4, to_countersignatory_value_sat),
 901         (6, feerate_per_kw),
 902         (8, htlcs),
 903         (10, keys),
 904         (12, built),
 905 }, {}, {});
 906
 907 impl CommitmentTransaction {
 908         /// Construct an object of the class while assigning transaction output indices to HTLCs.
 909         ///
 910         /// Populates HTLCOutputInCommitment.transaction_output_index in htlcs_with_aux.
 911         ///
 912         /// The generic T allows the caller to match the HTLC output index with auxiliary data.
 913         /// This auxiliary data is not stored in this object.
 914         ///
 915         /// Only include HTLCs that are above the dust limit for the channel.
 916         ///
 917         /// (C-not exported) due to the generic though we likely should expose a version without
 918         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 {
 919                 // Sort outputs and populate output indices while keeping track of the auxiliary data
 920                 let (outputs, htlcs) = Self::internal_build_outputs(&keys, to_broadcaster_value_sat, to_countersignatory_value_sat, htlcs_with_aux, channel_parameters).unwrap();
 921
 922                 let (obscured_commitment_transaction_number, txins) = Self::internal_build_inputs(commitment_number, channel_parameters);
 923                 let transaction = Self::make_transaction(obscured_commitment_transaction_number, txins, outputs);
 924                 let txid = transaction.txid();
 925                 CommitmentTransaction {
 926                         commitment_number,
 927                         to_broadcaster_value_sat,
 928                         to_countersignatory_value_sat,
 929                         feerate_per_kw,
 930                         htlcs,
 931                         keys,
 932                         built: BuiltCommitmentTransaction {
 933                                 transaction,
 934                                 txid
 935                         },
 936                 }
 937         }
 938
 939         fn internal_rebuild_transaction(&self, keys: &TxCreationKeys, channel_parameters: &DirectedChannelTransactionParameters) -> Result<BuiltCommitmentTransaction, ()> {
 940                 let (obscured_commitment_transaction_number, txins) = Self::internal_build_inputs(self.commitment_number, channel_parameters);
 941
 942                 let mut htlcs_with_aux = self.htlcs.iter().map(|h| (h.clone(), ())).collect();
 943                 let (outputs, _) = Self::internal_build_outputs(keys, self.to_broadcaster_value_sat, self.to_countersignatory_value_sat, &mut htlcs_with_aux, channel_parameters)?;
 944
 945                 let transaction = Self::make_transaction(obscured_commitment_transaction_number, txins, outputs);
 946                 let txid = transaction.txid();
 947                 let built_transaction = BuiltCommitmentTransaction {
 948                         transaction,
 949                         txid
 950                 };
 951                 Ok(built_transaction)
 952         }
 953
 954         fn make_transaction(obscured_commitment_transaction_number: u64, txins: Vec<TxIn>, outputs: Vec<TxOut>) -> Transaction {
 955                 Transaction {
 956                         version: 2,
 957                         lock_time: ((0x20 as u32) << 8 * 3) | ((obscured_commitment_transaction_number & 0xffffffu64) as u32),
 958                         input: txins,
 959                         output: outputs,
 960                 }
 961         }
 962
 963         // This is used in two cases:
 964         // - initial sorting of outputs / HTLCs in the constructor, in which case T is auxiliary data the
 965         //   caller needs to have sorted together with the HTLCs so it can keep track of the output index
 966         // - building of a bitcoin transaction during a verify() call, in which case T is just ()
 967         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>), ()> {
 968                 let countersignatory_pubkeys = channel_parameters.countersignatory_pubkeys();
 969                 let contest_delay = channel_parameters.contest_delay();
 970
 971                 let mut txouts: Vec<(TxOut, Option<&mut HTLCOutputInCommitment>)> = Vec::new();
 972
 973                 if to_countersignatory_value_sat > 0 {
 974                         let script = script_for_p2wpkh(&countersignatory_pubkeys.payment_point);
 975                         txouts.push((
 976                                 TxOut {
 977                                         script_pubkey: script.clone(),
 978                                         value: to_countersignatory_value_sat,
 979                                 },
 980                                 None,
 981                         ))
 982                 }
 983
 984                 if to_broadcaster_value_sat > 0 {
 985                         let redeem_script = get_revokeable_redeemscript(
 986                                 &keys.revocation_key,
 987                                 contest_delay,
 988                                 &keys.broadcaster_delayed_payment_key,
 989                         );
 990                         txouts.push((
 991                                 TxOut {
 992                                         script_pubkey: redeem_script.to_v0_p2wsh(),
 993                                         value: to_broadcaster_value_sat,
 994                                 },
 995                                 None,
 996                         ));
 997                 }
 998
 999                 let mut htlcs = Vec::with_capacity(htlcs_with_aux.len());
1000                 for (htlc, _) in htlcs_with_aux {
1001                         let script = chan_utils::get_htlc_redeemscript(&htlc, &keys);
1002                         let txout = TxOut {
1003                                 script_pubkey: script.to_v0_p2wsh(),
1004                                 value: htlc.amount_msat / 1000,
1005                         };
1006                         txouts.push((txout, Some(htlc)));
1007                 }
1008
1009                 // Sort output in BIP-69 order (amount, scriptPubkey).  Tie-breaks based on HTLC
1010                 // CLTV expiration height.
1011                 sort_outputs(&mut txouts, |a, b| {
1012                         if let &Some(ref a_htlcout) = a {
1013                                 if let &Some(ref b_htlcout) = b {
1014                                         a_htlcout.cltv_expiry.cmp(&b_htlcout.cltv_expiry)
1015                                                 // Note that due to hash collisions, we have to have a fallback comparison
1016                                                 // here for fuzztarget mode (otherwise at least chanmon_fail_consistency
1017                                                 // may fail)!
1018                                                 .then(a_htlcout.payment_hash.0.cmp(&b_htlcout.payment_hash.0))
1019                                 // For non-HTLC outputs, if they're copying our SPK we don't really care if we
1020                                 // close the channel due to mismatches - they're doing something dumb:
1021                                 } else { cmp::Ordering::Equal }
1022                         } else { cmp::Ordering::Equal }
1023                 });
1024
1025                 let mut outputs = Vec::with_capacity(txouts.len());
1026                 for (idx, out) in txouts.drain(..).enumerate() {
1027                         if let Some(htlc) = out.1 {
1028                                 htlc.transaction_output_index = Some(idx as u32);
1029                                 htlcs.push(htlc.clone());
1030                         }
1031                         outputs.push(out.0);
1032                 }
1033                 Ok((outputs, htlcs))
1034         }
1035
1036         fn internal_build_inputs(commitment_number: u64, channel_parameters: &DirectedChannelTransactionParameters) -> (u64, Vec<TxIn>) {
1037                 let broadcaster_pubkeys = channel_parameters.broadcaster_pubkeys();
1038                 let countersignatory_pubkeys = channel_parameters.countersignatory_pubkeys();
1039                 let commitment_transaction_number_obscure_factor = get_commitment_transaction_number_obscure_factor(
1040                         &broadcaster_pubkeys.payment_point,
1041                         &countersignatory_pubkeys.payment_point,
1042                         channel_parameters.is_outbound(),
1043                 );
1044
1045                 let obscured_commitment_transaction_number =
1046                         commitment_transaction_number_obscure_factor ^ (INITIAL_COMMITMENT_NUMBER - commitment_number);
1047
1048                 let txins = {
1049                         let mut ins: Vec<TxIn> = Vec::new();
1050                         ins.push(TxIn {
1051                                 previous_output: channel_parameters.funding_outpoint(),
1052                                 script_sig: Script::new(),
1053                                 sequence: ((0x80 as u32) << 8 * 3)
1054                                         | ((obscured_commitment_transaction_number >> 3 * 8) as u32),
1055                                 witness: Vec::new(),
1056                         });
1057                         ins
1058                 };
1059                 (obscured_commitment_transaction_number, txins)
1060         }
1061
1062         /// The backwards-counting commitment number
1063         pub fn commitment_number(&self) -> u64 {
1064                 self.commitment_number
1065         }
1066
1067         /// The value to be sent to the broadcaster
1068         pub fn to_broadcaster_value_sat(&self) -> u64 {
1069                 self.to_broadcaster_value_sat
1070         }
1071
1072         /// The value to be sent to the counterparty
1073         pub fn to_countersignatory_value_sat(&self) -> u64 {
1074                 self.to_countersignatory_value_sat
1075         }
1076
1077         /// The feerate paid per 1000-weight-unit in this commitment transaction.
1078         pub fn feerate_per_kw(&self) -> u32 {
1079                 self.feerate_per_kw
1080         }
1081
1082         /// The non-dust HTLCs (direction, amt, height expiration, hash, transaction output index)
1083         /// which were included in this commitment transaction in output order.
1084         /// The transaction index is always populated.
1085         ///
1086         /// (C-not exported) as we cannot currently convert Vec references to/from C, though we should
1087         /// expose a less effecient version which creates a Vec of references in the future.
1088         pub fn htlcs(&self) -> &Vec<HTLCOutputInCommitment> {
1089                 &self.htlcs
1090         }
1091
1092         /// Trust our pre-built transaction and derived transaction creation public keys.
1093         ///
1094         /// Applies a wrapper which allows access to these fields.
1095         ///
1096         /// This should only be used if you fully trust the builder of this object.  It should not
1097         ///     be used by an external signer - instead use the verify function.
1098         pub fn trust(&self) -> TrustedCommitmentTransaction {
1099                 TrustedCommitmentTransaction { inner: self }
1100         }
1101
1102         /// Verify our pre-built transaction and derived transaction creation public keys.
1103         ///
1104         /// Applies a wrapper which allows access to these fields.
1105         ///
1106         /// An external validating signer must call this method before signing
1107         /// or using the built transaction.
1108         pub fn verify<T: secp256k1::Signing + secp256k1::Verification>(&self, channel_parameters: &DirectedChannelTransactionParameters, broadcaster_keys: &ChannelPublicKeys, countersignatory_keys: &ChannelPublicKeys, secp_ctx: &Secp256k1<T>) -> Result<TrustedCommitmentTransaction, ()> {
1109                 // This is the only field of the key cache that we trust
1110                 let per_commitment_point = self.keys.per_commitment_point;
1111                 let keys = TxCreationKeys::from_channel_static_keys(&per_commitment_point, broadcaster_keys, countersignatory_keys, secp_ctx).unwrap();
1112                 if keys != self.keys {
1113                         return Err(());
1114                 }
1115                 let tx = self.internal_rebuild_transaction(&keys, channel_parameters)?;
1116                 if self.built.transaction != tx.transaction || self.built.txid != tx.txid {
1117                         return Err(());
1118                 }
1119                 Ok(TrustedCommitmentTransaction { inner: self })
1120         }
1121 }
1122
1123 /// A wrapper on CommitmentTransaction indicating that the derived fields (the built bitcoin
1124 /// transaction and the transaction creation keys) are trusted.
1125 ///
1126 /// See trust() and verify() functions on CommitmentTransaction.
1127 ///
1128 /// This structure implements Deref.
1129 pub struct TrustedCommitmentTransaction<'a> {
1130         inner: &'a CommitmentTransaction,
1131 }
1132
1133 impl<'a> Deref for TrustedCommitmentTransaction<'a> {
1134         type Target = CommitmentTransaction;
1135
1136         fn deref(&self) -> &Self::Target { self.inner }
1137 }
1138
1139 impl<'a> TrustedCommitmentTransaction<'a> {
1140         /// The transaction ID of the built Bitcoin transaction
1141         pub fn txid(&self) -> Txid {
1142                 self.inner.built.txid
1143         }
1144
1145         /// The pre-built Bitcoin commitment transaction
1146         pub fn built_transaction(&self) -> &BuiltCommitmentTransaction {
1147                 &self.inner.built
1148         }
1149
1150         /// The pre-calculated transaction creation public keys.
1151         pub fn keys(&self) -> &TxCreationKeys {
1152                 &self.inner.keys
1153         }
1154
1155         /// Get a signature for each HTLC which was included in the commitment transaction (ie for
1156         /// which HTLCOutputInCommitment::transaction_output_index.is_some()).
1157         ///
1158         /// The returned Vec has one entry for each HTLC, and in the same order.
1159         pub fn get_htlc_sigs<T: secp256k1::Signing>(&self, htlc_base_key: &SecretKey, channel_parameters: &DirectedChannelTransactionParameters, secp_ctx: &Secp256k1<T>) -> Result<Vec<Signature>, ()> {
1160                 let inner = self.inner;
1161                 let keys = &inner.keys;
1162                 let txid = inner.built.txid;
1163                 let mut ret = Vec::with_capacity(inner.htlcs.len());
1164                 let holder_htlc_key = derive_private_key(secp_ctx, &inner.keys.per_commitment_point, htlc_base_key).map_err(|_| ())?;
1165
1166                 for this_htlc in inner.htlcs.iter() {
1167                         assert!(this_htlc.transaction_output_index.is_some());
1168                         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);
1169
1170                         let htlc_redeemscript = get_htlc_redeemscript_with_explicit_keys(&this_htlc, &keys.broadcaster_htlc_key, &keys.countersignatory_htlc_key, &keys.revocation_key);
1171
1172                         let sighash = hash_to_message!(&bip143::SigHashCache::new(&htlc_tx).signature_hash(0, &htlc_redeemscript, this_htlc.amount_msat / 1000, SigHashType::All)[..]);
1173                         ret.push(secp_ctx.sign(&sighash, &holder_htlc_key));
1174                 }
1175                 Ok(ret)
1176         }
1177
1178         /// Gets a signed HTLC transaction given a preimage (for !htlc.offered) and the holder HTLC transaction signature.
1179         pub(crate) fn get_signed_htlc_tx(&self, channel_parameters: &DirectedChannelTransactionParameters, htlc_index: usize, counterparty_signature: &Signature, signature: &Signature, preimage: &Option<PaymentPreimage>) -> Transaction {
1180                 let inner = self.inner;
1181                 let keys = &inner.keys;
1182                 let txid = inner.built.txid;
1183                 let this_htlc = &inner.htlcs[htlc_index];
1184                 assert!(this_htlc.transaction_output_index.is_some());
1185                 // if we don't have preimage for an HTLC-Success, we can't generate an HTLC transaction.
1186                 if !this_htlc.offered && preimage.is_none() { unreachable!(); }
1187                 // Further, we should never be provided the preimage for an HTLC-Timeout transaction.
1188                 if  this_htlc.offered && preimage.is_some() { unreachable!(); }
1189
1190                 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);
1191
1192                 let htlc_redeemscript = get_htlc_redeemscript_with_explicit_keys(&this_htlc, &keys.broadcaster_htlc_key, &keys.countersignatory_htlc_key, &keys.revocation_key);
1193
1194                 // First push the multisig dummy, note that due to BIP147 (NULLDUMMY) it must be a zero-length element.
1195                 htlc_tx.input[0].witness.push(Vec::new());
1196
1197                 htlc_tx.input[0].witness.push(counterparty_signature.serialize_der().to_vec());
1198                 htlc_tx.input[0].witness.push(signature.serialize_der().to_vec());
1199                 htlc_tx.input[0].witness[1].push(SigHashType::All as u8);
1200                 htlc_tx.input[0].witness[2].push(SigHashType::All as u8);
1201
1202                 if this_htlc.offered {
1203                         // Due to BIP146 (MINIMALIF) this must be a zero-length element to relay.
1204                         htlc_tx.input[0].witness.push(Vec::new());
1205                 } else {
1206                         htlc_tx.input[0].witness.push(preimage.unwrap().0.to_vec());
1207                 }
1208
1209                 htlc_tx.input[0].witness.push(htlc_redeemscript.as_bytes().to_vec());
1210                 htlc_tx
1211         }
1212 }
1213
1214 /// Get the transaction number obscure factor
1215 pub fn get_commitment_transaction_number_obscure_factor(
1216         broadcaster_payment_basepoint: &PublicKey,
1217         countersignatory_payment_basepoint: &PublicKey,
1218         outbound_from_broadcaster: bool,
1219 ) -> u64 {
1220         let mut sha = Sha256::engine();
1221
1222         if outbound_from_broadcaster {
1223                 sha.input(&broadcaster_payment_basepoint.serialize());
1224                 sha.input(&countersignatory_payment_basepoint.serialize());
1225         } else {
1226                 sha.input(&countersignatory_payment_basepoint.serialize());
1227                 sha.input(&broadcaster_payment_basepoint.serialize());
1228         }
1229         let res = Sha256::from_engine(sha).into_inner();
1230
1231         ((res[26] as u64) << 5 * 8)
1232                 | ((res[27] as u64) << 4 * 8)
1233                 | ((res[28] as u64) << 3 * 8)
1234                 | ((res[29] as u64) << 2 * 8)
1235                 | ((res[30] as u64) << 1 * 8)
1236                 | ((res[31] as u64) << 0 * 8)
1237 }
1238
1239 fn script_for_p2wpkh(key: &PublicKey) -> Script {
1240         Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0)
1241                 .push_slice(&WPubkeyHash::hash(&key.serialize())[..])
1242                 .into_script()
1243 }
1244
1245 #[cfg(test)]
1246 mod tests {
1247         use super::CounterpartyCommitmentSecrets;
1248         use hex;
1249
1250         #[test]
1251         fn test_per_commitment_storage() {
1252                 // Test vectors from BOLT 3:
1253                 let mut secrets: Vec<[u8; 32]> = Vec::new();
1254                 let mut monitor;
1255
1256                 macro_rules! test_secrets {
1257                         () => {
1258                                 let mut idx = 281474976710655;
1259                                 for secret in secrets.iter() {
1260                                         assert_eq!(monitor.get_secret(idx).unwrap(), *secret);
1261                                         idx -= 1;
1262                                 }
1263                                 assert_eq!(monitor.get_min_seen_secret(), idx + 1);
1264                                 assert!(monitor.get_secret(idx).is_none());
1265                         };
1266                 }
1267
1268                 {
1269                         // insert_secret correct sequence
1270                         monitor = CounterpartyCommitmentSecrets::new();
1271                         secrets.clear();
1272
1273                         secrets.push([0; 32]);
1274                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1275                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1276                         test_secrets!();
1277
1278                         secrets.push([0; 32]);
1279                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1280                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1281                         test_secrets!();
1282
1283                         secrets.push([0; 32]);
1284                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1285                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1286                         test_secrets!();
1287
1288                         secrets.push([0; 32]);
1289                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1290                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
1291                         test_secrets!();
1292
1293                         secrets.push([0; 32]);
1294                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
1295                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
1296                         test_secrets!();
1297
1298                         secrets.push([0; 32]);
1299                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
1300                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
1301                         test_secrets!();
1302
1303                         secrets.push([0; 32]);
1304                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
1305                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
1306                         test_secrets!();
1307
1308                         secrets.push([0; 32]);
1309                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
1310                         monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap();
1311                         test_secrets!();
1312                 }
1313
1314                 {
1315                         // insert_secret #1 incorrect
1316                         monitor = CounterpartyCommitmentSecrets::new();
1317                         secrets.clear();
1318
1319                         secrets.push([0; 32]);
1320                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
1321                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1322                         test_secrets!();
1323
1324                         secrets.push([0; 32]);
1325                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1326                         assert!(monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).is_err());
1327                 }
1328
1329                 {
1330                         // insert_secret #2 incorrect (#1 derived from incorrect)
1331                         monitor = CounterpartyCommitmentSecrets::new();
1332                         secrets.clear();
1333
1334                         secrets.push([0; 32]);
1335                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
1336                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1337                         test_secrets!();
1338
1339                         secrets.push([0; 32]);
1340                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("dddc3a8d14fddf2b68fa8c7fbad2748274937479dd0f8930d5ebb4ab6bd866a3").unwrap());
1341                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1342                         test_secrets!();
1343
1344                         secrets.push([0; 32]);
1345                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1346                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1347                         test_secrets!();
1348
1349                         secrets.push([0; 32]);
1350                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1351                         assert!(monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).is_err());
1352                 }
1353
1354                 {
1355                         // insert_secret #3 incorrect
1356                         monitor = CounterpartyCommitmentSecrets::new();
1357                         secrets.clear();
1358
1359                         secrets.push([0; 32]);
1360                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1361                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1362                         test_secrets!();
1363
1364                         secrets.push([0; 32]);
1365                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1366                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1367                         test_secrets!();
1368
1369                         secrets.push([0; 32]);
1370                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c51a18b13e8527e579ec56365482c62f180b7d5760b46e9477dae59e87ed423a").unwrap());
1371                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1372                         test_secrets!();
1373
1374                         secrets.push([0; 32]);
1375                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1376                         assert!(monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).is_err());
1377                 }
1378
1379                 {
1380                         // insert_secret #4 incorrect (1,2,3 derived from incorrect)
1381                         monitor = CounterpartyCommitmentSecrets::new();
1382                         secrets.clear();
1383
1384                         secrets.push([0; 32]);
1385                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
1386                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1387                         test_secrets!();
1388
1389                         secrets.push([0; 32]);
1390                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("dddc3a8d14fddf2b68fa8c7fbad2748274937479dd0f8930d5ebb4ab6bd866a3").unwrap());
1391                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1392                         test_secrets!();
1393
1394                         secrets.push([0; 32]);
1395                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c51a18b13e8527e579ec56365482c62f180b7d5760b46e9477dae59e87ed423a").unwrap());
1396                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1397                         test_secrets!();
1398
1399                         secrets.push([0; 32]);
1400                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("ba65d7b0ef55a3ba300d4e87af29868f394f8f138d78a7011669c79b37b936f4").unwrap());
1401                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
1402                         test_secrets!();
1403
1404                         secrets.push([0; 32]);
1405                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
1406                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
1407                         test_secrets!();
1408
1409                         secrets.push([0; 32]);
1410                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
1411                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
1412                         test_secrets!();
1413
1414                         secrets.push([0; 32]);
1415                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
1416                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
1417                         test_secrets!();
1418
1419                         secrets.push([0; 32]);
1420                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
1421                         assert!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).is_err());
1422                 }
1423
1424                 {
1425                         // insert_secret #5 incorrect
1426                         monitor = CounterpartyCommitmentSecrets::new();
1427                         secrets.clear();
1428
1429                         secrets.push([0; 32]);
1430                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1431                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1432                         test_secrets!();
1433
1434                         secrets.push([0; 32]);
1435                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1436                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1437                         test_secrets!();
1438
1439                         secrets.push([0; 32]);
1440                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1441                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1442                         test_secrets!();
1443
1444                         secrets.push([0; 32]);
1445                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1446                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
1447                         test_secrets!();
1448
1449                         secrets.push([0; 32]);
1450                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("631373ad5f9ef654bb3dade742d09504c567edd24320d2fcd68e3cc47e2ff6a6").unwrap());
1451                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
1452                         test_secrets!();
1453
1454                         secrets.push([0; 32]);
1455                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
1456                         assert!(monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).is_err());
1457                 }
1458
1459                 {
1460                         // insert_secret #6 incorrect (5 derived from incorrect)
1461                         monitor = CounterpartyCommitmentSecrets::new();
1462                         secrets.clear();
1463
1464                         secrets.push([0; 32]);
1465                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1466                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1467                         test_secrets!();
1468
1469                         secrets.push([0; 32]);
1470                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1471                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1472                         test_secrets!();
1473
1474                         secrets.push([0; 32]);
1475                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1476                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1477                         test_secrets!();
1478
1479                         secrets.push([0; 32]);
1480                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1481                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
1482                         test_secrets!();
1483
1484                         secrets.push([0; 32]);
1485                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("631373ad5f9ef654bb3dade742d09504c567edd24320d2fcd68e3cc47e2ff6a6").unwrap());
1486                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
1487                         test_secrets!();
1488
1489                         secrets.push([0; 32]);
1490                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("b7e76a83668bde38b373970155c868a653304308f9896692f904a23731224bb1").unwrap());
1491                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
1492                         test_secrets!();
1493
1494                         secrets.push([0; 32]);
1495                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
1496                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
1497                         test_secrets!();
1498
1499                         secrets.push([0; 32]);
1500                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
1501                         assert!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).is_err());
1502                 }
1503
1504                 {
1505                         // insert_secret #7 incorrect
1506                         monitor = CounterpartyCommitmentSecrets::new();
1507                         secrets.clear();
1508
1509                         secrets.push([0; 32]);
1510                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1511                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1512                         test_secrets!();
1513
1514                         secrets.push([0; 32]);
1515                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1516                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1517                         test_secrets!();
1518
1519                         secrets.push([0; 32]);
1520                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1521                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1522                         test_secrets!();
1523
1524                         secrets.push([0; 32]);
1525                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1526                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
1527                         test_secrets!();
1528
1529                         secrets.push([0; 32]);
1530                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
1531                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
1532                         test_secrets!();
1533
1534                         secrets.push([0; 32]);
1535                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
1536                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
1537                         test_secrets!();
1538
1539                         secrets.push([0; 32]);
1540                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("e7971de736e01da8ed58b94c2fc216cb1dca9e326f3a96e7194fe8ea8af6c0a3").unwrap());
1541                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
1542                         test_secrets!();
1543
1544                         secrets.push([0; 32]);
1545                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
1546                         assert!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).is_err());
1547                 }
1548
1549                 {
1550                         // insert_secret #8 incorrect
1551                         monitor = CounterpartyCommitmentSecrets::new();
1552                         secrets.clear();
1553
1554                         secrets.push([0; 32]);
1555                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1556                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1557                         test_secrets!();
1558
1559                         secrets.push([0; 32]);
1560                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1561                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1562                         test_secrets!();
1563
1564                         secrets.push([0; 32]);
1565                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1566                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1567                         test_secrets!();
1568
1569                         secrets.push([0; 32]);
1570                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1571                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
1572                         test_secrets!();
1573
1574                         secrets.push([0; 32]);
1575                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
1576                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
1577                         test_secrets!();
1578
1579                         secrets.push([0; 32]);
1580                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
1581                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
1582                         test_secrets!();
1583
1584                         secrets.push([0; 32]);
1585                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
1586                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
1587                         test_secrets!();
1588
1589                         secrets.push([0; 32]);
1590                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a7efbc61aac46d34f77778bac22c8a20c6a46ca460addc49009bda875ec88fa4").unwrap());
1591                         assert!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).is_err());
1592                 }
1593         }
1594 }