_ Git - rust-lightning/blob - src/ln/channelmonitor.rs

   1 use bitcoin::blockdata::block::BlockHeader;
   2 use bitcoin::blockdata::transaction::{TxIn,TxOut,SigHashType,Transaction};
   3 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
   4 use bitcoin::blockdata::script::Script;
   5 use bitcoin::network::serialize;
   6 use bitcoin::util::hash::Sha256dHash;
   7 use bitcoin::util::bip143;
   8
   9 use crypto::digest::Digest;
  10
  11 use secp256k1::{Secp256k1,Message,Signature};
  12 use secp256k1::key::{SecretKey,PublicKey};
  13 use secp256k1;
  14
  15 use ln::msgs::HandleError;
  16 use ln::chan_utils;
  17 use ln::chan_utils::HTLCOutputInCommitment;
  18 use chain::chaininterface::{ChainListener, ChainWatchInterface, BroadcasterInterface};
  19 use chain::transaction::OutPoint;
  20 use util::sha2::Sha256;
  21 use util::byte_utils;
  22
  23 use std::collections::HashMap;
  24 use std::sync::{Arc,Mutex};
  25 use std::{hash,cmp};
  26
  27 pub enum ChannelMonitorUpdateErr {
  28         /// Used to indicate a temporary failure (eg connection to a watchtower failed, but is expected
  29         /// to succeed at some point in the future).
  30         /// Such a failure will "freeze" a channel, preventing us from revoking old states or
  31         /// submitting new commitment transactions to the remote party.
  32         /// ChannelManager::test_restore_channel_monitor can be used to retry the update(s) and restore
  33         /// the channel to an operational state.
  34         TemporaryFailure,
  35         /// Used to indicate no further channel monitor updates will be allowed (eg we've moved on to a
  36         /// different watchtower and cannot update with all watchtowers that were previously informed
  37         /// of this channel). This will force-close the channel in question.
  38         PermanentFailure,
  39 }
  40
  41 /// Simple trait indicating ability to track a set of ChannelMonitors and multiplex events between
  42 /// them. Generally should be implemented by keeping a local SimpleManyChannelMonitor and passing
  43 /// events to it, while also taking any add_update_monitor events and passing them to some remote
  44 /// server(s).
  45 /// Note that any updates to a channel's monitor *must* be applied to each instance of the
  46 /// channel's monitor everywhere (including remote watchtowers) *before* this function returns. If
  47 /// an update occurs and a remote watchtower is left with old state, it may broadcast transactions
  48 /// which we have revoked, allowing our counterparty to claim all funds in the channel!
  49 pub trait ManyChannelMonitor: Send + Sync {
  50         /// Adds or updates a monitor for the given `funding_txo`.
  51         fn add_update_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor) -> Result<(), ChannelMonitorUpdateErr>;
  52 }
  53
  54 /// A simple implementation of a ManyChannelMonitor and ChainListener. Can be used to create a
  55 /// watchtower or watch our own channels.
  56 /// Note that you must provide your own key by which to refer to channels.
  57 /// If you're accepting remote monitors (ie are implementing a watchtower), you must verify that
  58 /// users cannot overwrite a given channel by providing a duplicate key. ie you should probably
  59 /// index by a PublicKey which is required to sign any updates.
  60 /// If you're using this for local monitoring of your own channels, you probably want to use
  61 /// `OutPoint` as the key, which will give you a ManyChannelMonitor implementation.
  62 pub struct SimpleManyChannelMonitor<Key> {
  63         monitors: Mutex<HashMap<Key, ChannelMonitor>>,
  64         chain_monitor: Arc<ChainWatchInterface>,
  65         broadcaster: Arc<BroadcasterInterface>
  66 }
  67
  68 impl<Key : Send + cmp::Eq + hash::Hash> ChainListener for SimpleManyChannelMonitor<Key> {
  69         fn block_connected(&self, _header: &BlockHeader, height: u32, txn_matched: &[&Transaction], _indexes_of_txn_matched: &[u32]) {
  70                 let monitors = self.monitors.lock().unwrap();
  71                 for monitor in monitors.values() {
  72                         monitor.block_connected(txn_matched, height, &*self.broadcaster);
  73                 }
  74         }
  75
  76         fn block_disconnected(&self, _: &BlockHeader) { }
  77 }
  78
  79 impl<Key : Send + cmp::Eq + hash::Hash + 'static> SimpleManyChannelMonitor<Key> {
  80         pub fn new(chain_monitor: Arc<ChainWatchInterface>, broadcaster: Arc<BroadcasterInterface>) -> Arc<SimpleManyChannelMonitor<Key>> {
  81                 let res = Arc::new(SimpleManyChannelMonitor {
  82                         monitors: Mutex::new(HashMap::new()),
  83                         chain_monitor,
  84                         broadcaster
  85                 });
  86                 let weak_res = Arc::downgrade(&res);
  87                 res.chain_monitor.register_listener(weak_res);
  88                 res
  89         }
  90
  91         pub fn add_update_monitor_by_key(&self, key: Key, monitor: ChannelMonitor) -> Result<(), HandleError> {
  92                 let mut monitors = self.monitors.lock().unwrap();
  93                 match monitors.get_mut(&key) {
  94                         Some(orig_monitor) => return orig_monitor.insert_combine(monitor),
  95                         None => {}
  96                 };
  97                 match &monitor.funding_txo {
  98                         &None => self.chain_monitor.watch_all_txn(),
  99                         &Some((ref outpoint, ref script)) => {
 100                                 self.chain_monitor.install_watch_script(script);
 101                                 self.chain_monitor.install_watch_outpoint((outpoint.txid, outpoint.index as u32), script);
 102                         },
 103                 }
 104                 monitors.insert(key, monitor);
 105                 Ok(())
 106         }
 107 }
 108
 109 impl ManyChannelMonitor for SimpleManyChannelMonitor<OutPoint> {
 110         fn add_update_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor) -> Result<(), ChannelMonitorUpdateErr> {
 111                 match self.add_update_monitor_by_key(funding_txo, monitor) {
 112                         Ok(_) => Ok(()),
 113                         Err(_) => Err(ChannelMonitorUpdateErr::PermanentFailure),
 114                 }
 115         }
 116 }
 117
 118 /// If an HTLC expires within this many blocks, don't try to claim it in a shared transaction,
 119 /// instead claiming it in its own individual transaction.
 120 const CLTV_SHARED_CLAIM_BUFFER: u32 = 12;
 121 /// If an HTLC expires within this many blocks, force-close the channel to broadcast the
 122 /// HTLC-Success transaction.
 123 const CLTV_CLAIM_BUFFER: u32 = 6;
 124
 125 #[derive(Clone, PartialEq)]
 126 enum KeyStorage {
 127         PrivMode {
 128                 revocation_base_key: SecretKey,
 129                 htlc_base_key: SecretKey,
 130         },
 131         SigsMode {
 132                 revocation_base_key: PublicKey,
 133                 htlc_base_key: PublicKey,
 134                 sigs: HashMap<Sha256dHash, Signature>,
 135         }
 136 }
 137
 138 #[derive(Clone, PartialEq)]
 139 struct LocalSignedTx {
 140         /// txid of the transaction in tx, just used to make comparison faster
 141         txid: Sha256dHash,
 142         tx: Transaction,
 143         revocation_key: PublicKey,
 144         a_htlc_key: PublicKey,
 145         b_htlc_key: PublicKey,
 146         delayed_payment_key: PublicKey,
 147         feerate_per_kw: u64,
 148         htlc_outputs: Vec<(HTLCOutputInCommitment, Signature, Signature)>,
 149 }
 150
 151 const SERIALIZATION_VERSION: u8 = 1;
 152 const MIN_SERIALIZATION_VERSION: u8 = 1;
 153
 154 pub struct ChannelMonitor {
 155         funding_txo: Option<(OutPoint, Script)>,
 156         commitment_transaction_number_obscure_factor: u64,
 157
 158         key_storage: KeyStorage,
 159         delayed_payment_base_key: PublicKey,
 160         their_htlc_base_key: Option<PublicKey>,
 161         // first is the idx of the first of the two revocation points
 162         their_cur_revocation_points: Option<(u64, PublicKey, Option<PublicKey>)>,
 163
 164         our_to_self_delay: u16,
 165         their_to_self_delay: Option<u16>,
 166
 167         old_secrets: [([u8; 32], u64); 49],
 168         remote_claimable_outpoints: HashMap<Sha256dHash, Vec<HTLCOutputInCommitment>>,
 169         /// We cannot identify HTLC-Success or HTLC-Timeout transactions by themselves on the chain.
 170         /// Nor can we figure out their commitment numbers without the commitment transaction they are
 171         /// spending. Thus, in order to claim them via revocation key, we track all the remote
 172         /// commitment transactions which we find on-chain, mapping them to the commitment number which
 173         /// can be used to derive the revocation key and claim the transactions.
 174         remote_commitment_txn_on_chain: Mutex<HashMap<Sha256dHash, u64>>,
 175         /// Cache used to make pruning of payment_preimages faster.
 176         /// Maps payment_hash values to commitment numbers for remote transactions for non-revoked
 177         /// remote transactions (ie should remain pretty small).
 178         /// Serialized to disk but should generally not be sent to Watchtowers.
 179         remote_hash_commitment_number: HashMap<[u8; 32], u64>,
 180
 181         // We store two local commitment transactions to avoid any race conditions where we may update
 182         // some monitors (potentially on watchtowers) but then fail to update others, resulting in the
 183         // various monitors for one channel being out of sync, and us broadcasting a local
 184         // transaction for which we have deleted claim information on some watchtowers.
 185         prev_local_signed_commitment_tx: Option<LocalSignedTx>,
 186         current_local_signed_commitment_tx: Option<LocalSignedTx>,
 187
 188         payment_preimages: HashMap<[u8; 32], [u8; 32]>,
 189
 190         destination_script: Script,
 191         secp_ctx: Secp256k1<secp256k1::All>, //TODO: dedup this a bit...
 192 }
 193 impl Clone for ChannelMonitor {
 194         fn clone(&self) -> Self {
 195                 ChannelMonitor {
 196                         funding_txo: self.funding_txo.clone(),
 197                         commitment_transaction_number_obscure_factor: self.commitment_transaction_number_obscure_factor.clone(),
 198
 199                         key_storage: self.key_storage.clone(),
 200                         delayed_payment_base_key: self.delayed_payment_base_key.clone(),
 201                         their_htlc_base_key: self.their_htlc_base_key.clone(),
 202                         their_cur_revocation_points: self.their_cur_revocation_points.clone(),
 203
 204                         our_to_self_delay: self.our_to_self_delay,
 205                         their_to_self_delay: self.their_to_self_delay,
 206
 207                         old_secrets: self.old_secrets.clone(),
 208                         remote_claimable_outpoints: self.remote_claimable_outpoints.clone(),
 209                         remote_commitment_txn_on_chain: Mutex::new((*self.remote_commitment_txn_on_chain.lock().unwrap()).clone()),
 210                         remote_hash_commitment_number: self.remote_hash_commitment_number.clone(),
 211
 212                         prev_local_signed_commitment_tx: self.prev_local_signed_commitment_tx.clone(),
 213                         current_local_signed_commitment_tx: self.current_local_signed_commitment_tx.clone(),
 214
 215                         payment_preimages: self.payment_preimages.clone(),
 216
 217                         destination_script: self.destination_script.clone(),
 218                         secp_ctx: self.secp_ctx.clone(),
 219                 }
 220         }
 221 }
 222
 223 #[cfg(any(test, feature = "fuzztarget"))]
 224 /// Used only in testing and fuzztarget to check serialization roundtrips don't change the
 225 /// underlying object
 226 impl PartialEq for ChannelMonitor {
 227         fn eq(&self, other: &Self) -> bool {
 228                 if self.funding_txo != other.funding_txo ||
 229                         self.commitment_transaction_number_obscure_factor != other.commitment_transaction_number_obscure_factor ||
 230                         self.key_storage != other.key_storage ||
 231                         self.delayed_payment_base_key != other.delayed_payment_base_key ||
 232                         self.their_htlc_base_key != other.their_htlc_base_key ||
 233                         self.their_cur_revocation_points != other.their_cur_revocation_points ||
 234                         self.our_to_self_delay != other.our_to_self_delay ||
 235                         self.their_to_self_delay != other.their_to_self_delay ||
 236                         self.remote_claimable_outpoints != other.remote_claimable_outpoints ||
 237                         self.remote_hash_commitment_number != other.remote_hash_commitment_number ||
 238                         self.prev_local_signed_commitment_tx != other.prev_local_signed_commitment_tx ||
 239                         self.current_local_signed_commitment_tx != other.current_local_signed_commitment_tx ||
 240                         self.payment_preimages != other.payment_preimages ||
 241                         self.destination_script != other.destination_script
 242                 {
 243                         false
 244                 } else {
 245                         for (&(ref secret, ref idx), &(ref o_secret, ref o_idx)) in self.old_secrets.iter().zip(other.old_secrets.iter()) {
 246                                 if secret != o_secret || idx != o_idx {
 247                                         return false
 248                                 }
 249                         }
 250                         let us = self.remote_commitment_txn_on_chain.lock().unwrap();
 251                         let them = other.remote_commitment_txn_on_chain.lock().unwrap();
 252                         *us == *them
 253                 }
 254         }
 255 }
 256
 257 impl ChannelMonitor {
 258         pub fn new(revocation_base_key: &SecretKey, delayed_payment_base_key: &PublicKey, htlc_base_key: &SecretKey, our_to_self_delay: u16, destination_script: Script) -> ChannelMonitor {
 259                 ChannelMonitor {
 260                         funding_txo: None,
 261                         commitment_transaction_number_obscure_factor: 0,
 262
 263                         key_storage: KeyStorage::PrivMode {
 264                                 revocation_base_key: revocation_base_key.clone(),
 265                                 htlc_base_key: htlc_base_key.clone(),
 266                         },
 267                         delayed_payment_base_key: delayed_payment_base_key.clone(),
 268                         their_htlc_base_key: None,
 269                         their_cur_revocation_points: None,
 270
 271                         our_to_self_delay: our_to_self_delay,
 272                         their_to_self_delay: None,
 273
 274                         old_secrets: [([0; 32], 1 << 48); 49],
 275                         remote_claimable_outpoints: HashMap::new(),
 276                         remote_commitment_txn_on_chain: Mutex::new(HashMap::new()),
 277                         remote_hash_commitment_number: HashMap::new(),
 278
 279                         prev_local_signed_commitment_tx: None,
 280                         current_local_signed_commitment_tx: None,
 281
 282                         payment_preimages: HashMap::new(),
 283
 284                         destination_script: destination_script,
 285                         secp_ctx: Secp256k1::new(),
 286                 }
 287         }
 288
 289         #[inline]
 290         fn place_secret(idx: u64) -> u8 {
 291                 for i in 0..48 {
 292                         if idx & (1 << i) == (1 << i) {
 293                                 return i
 294                         }
 295                 }
 296                 48
 297         }
 298
 299         #[inline]
 300         fn derive_secret(secret: [u8; 32], bits: u8, idx: u64) -> [u8; 32] {
 301                 let mut res: [u8; 32] = secret;
 302                 for i in 0..bits {
 303                         let bitpos = bits - 1 - i;
 304                         if idx & (1 << bitpos) == (1 << bitpos) {
 305                                 res[(bitpos / 8) as usize] ^= 1 << (bitpos & 7);
 306                                 let mut sha = Sha256::new();
 307                                 sha.input(&res);
 308                                 sha.result(&mut res);
 309                         }
 310                 }
 311                 res
 312         }
 313
 314         /// Inserts a revocation secret into this channel monitor. Also optionally tracks the next
 315         /// revocation point which may be required to claim HTLC outputs which we know the preimage of
 316         /// in case the remote end force-closes using their latest state. Prunes old preimages if neither
 317         /// needed by local commitment transactions HTCLs nor by remote ones. Unless we haven't already seen remote
 318         /// commitment transaction's secret, they are de facto pruned (we can use revocation key).
 319         pub(super) fn provide_secret(&mut self, idx: u64, secret: [u8; 32], their_next_revocation_point: Option<(u64, PublicKey)>) -> Result<(), HandleError> {
 320                 let pos = ChannelMonitor::place_secret(idx);
 321                 for i in 0..pos {
 322                         let (old_secret, old_idx) = self.old_secrets[i as usize];
 323                         if ChannelMonitor::derive_secret(secret, pos, old_idx) != old_secret {
 324                                 return Err(HandleError{err: "Previous secret did not match new one", action: None})
 325                         }
 326                 }
 327                 self.old_secrets[pos as usize] = (secret, idx);
 328
 329                 if let Some(new_revocation_point) = their_next_revocation_point {
 330                         match self.their_cur_revocation_points {
 331                                 Some(old_points) => {
 332                                         if old_points.0 == new_revocation_point.0 + 1 {
 333                                                 self.their_cur_revocation_points = Some((old_points.0, old_points.1, Some(new_revocation_point.1)));
 334                                         } else if old_points.0 == new_revocation_point.0 + 2 {
 335                                                 if let Some(old_second_point) = old_points.2 {
 336                                                         self.their_cur_revocation_points = Some((old_points.0 - 1, old_second_point, Some(new_revocation_point.1)));
 337                                                 } else {
 338                                                         self.their_cur_revocation_points = Some((new_revocation_point.0, new_revocation_point.1, None));
 339                                                 }
 340                                         } else {
 341                                                 self.their_cur_revocation_points = Some((new_revocation_point.0, new_revocation_point.1, None));
 342                                         }
 343                                 },
 344                                 None => {
 345                                         self.their_cur_revocation_points = Some((new_revocation_point.0, new_revocation_point.1, None));
 346                                 }
 347                         }
 348                 }
 349
 350                 if !self.payment_preimages.is_empty() {
 351                         let local_signed_commitment_tx = self.current_local_signed_commitment_tx.as_ref().expect("Channel needs at least an initial commitment tx !");
 352                         let prev_local_signed_commitment_tx = self.prev_local_signed_commitment_tx.as_ref();
 353                         let min_idx = self.get_min_seen_secret();
 354                         let remote_hash_commitment_number = &mut self.remote_hash_commitment_number;
 355
 356                         self.payment_preimages.retain(|&k, _| {
 357                                 for &(ref htlc, _, _) in &local_signed_commitment_tx.htlc_outputs {
 358                                         if k == htlc.payment_hash {
 359                                                 return true
 360                                         }
 361                                 }
 362                                 if let Some(prev_local_commitment_tx) = prev_local_signed_commitment_tx {
 363                                         for &(ref htlc, _, _) in prev_local_commitment_tx.htlc_outputs.iter() {
 364                                                 if k == htlc.payment_hash {
 365                                                         return true
 366                                                 }
 367                                         }
 368                                 }
 369                                 let contains = if let Some(cn) = remote_hash_commitment_number.get(&k) {
 370                                         if *cn < min_idx {
 371                                                 return true
 372                                         }
 373                                         true
 374                                 } else { false };
 375                                 if contains {
 376                                         remote_hash_commitment_number.remove(&k);
 377                                 }
 378                                 false
 379                         });
 380                 }
 381
 382                 Ok(())
 383         }
 384
 385         /// Informs this monitor of the latest remote (ie non-broadcastable) commitment transaction.
 386         /// The monitor watches for it to be broadcasted and then uses the HTLC information (and
 387         /// possibly future revocation/preimage information) to claim outputs where possible.
 388         /// We cache also the mapping hash:commitment number to lighten pruning of old preimages by watchtowers.
 389         pub(super) fn provide_latest_remote_commitment_tx_info(&mut self, unsigned_commitment_tx: &Transaction, htlc_outputs: Vec<HTLCOutputInCommitment>, commitment_number: u64) {
 390                 // TODO: Encrypt the htlc_outputs data with the single-hash of the commitment transaction
 391                 // so that a remote monitor doesn't learn anything unless there is a malicious close.
 392                 // (only maybe, sadly we cant do the same for local info, as we need to be aware of
 393                 // timeouts)
 394                 for htlc in &htlc_outputs {
 395                         self.remote_hash_commitment_number.insert(htlc.payment_hash, commitment_number);
 396                 }
 397                 self.remote_claimable_outpoints.insert(unsigned_commitment_tx.txid(), htlc_outputs);
 398         }
 399
 400         /// Informs this monitor of the latest local (ie broadcastable) commitment transaction. The
 401         /// monitor watches for timeouts and may broadcast it if we approach such a timeout. Thus, it
 402         /// is important that any clones of this channel monitor (including remote clones) by kept
 403         /// up-to-date as our local commitment transaction is updated.
 404         /// Panics if set_their_to_self_delay has never been called.
 405         pub(super) fn provide_latest_local_commitment_tx_info(&mut self, signed_commitment_tx: Transaction, local_keys: chan_utils::TxCreationKeys, feerate_per_kw: u64, htlc_outputs: Vec<(HTLCOutputInCommitment, Signature, Signature)>) {
 406                 assert!(self.their_to_self_delay.is_some());
 407                 self.prev_local_signed_commitment_tx = self.current_local_signed_commitment_tx.take();
 408                 self.current_local_signed_commitment_tx = Some(LocalSignedTx {
 409                         txid: signed_commitment_tx.txid(),
 410                         tx: signed_commitment_tx,
 411                         revocation_key: local_keys.revocation_key,
 412                         a_htlc_key: local_keys.a_htlc_key,
 413                         b_htlc_key: local_keys.b_htlc_key,
 414                         delayed_payment_key: local_keys.a_delayed_payment_key,
 415                         feerate_per_kw,
 416                         htlc_outputs,
 417                 });
 418         }
 419
 420         /// Provides a payment_hash->payment_preimage mapping. Will be automatically pruned when all
 421         /// commitment_tx_infos which contain the payment hash have been revoked.
 422         pub(super) fn provide_payment_preimage(&mut self, payment_hash: &[u8; 32], payment_preimage: &[u8; 32]) {
 423                 self.payment_preimages.insert(payment_hash.clone(), payment_preimage.clone());
 424         }
 425
 426         pub fn insert_combine(&mut self, mut other: ChannelMonitor) -> Result<(), HandleError> {
 427                 if self.funding_txo.is_some() {
 428                         // We should be able to compare the entire funding_txo, but in fuzztarget its trivially
 429                         // easy to collide the funding_txo hash and have a different scriptPubKey.
 430                         if other.funding_txo.is_some() && other.funding_txo.as_ref().unwrap().0 != self.funding_txo.as_ref().unwrap().0 {
 431                                 return Err(HandleError{err: "Funding transaction outputs are not identical!", action: None});
 432                         }
 433                 } else {
 434                         self.funding_txo = other.funding_txo.take();
 435                 }
 436                 let other_min_secret = other.get_min_seen_secret();
 437                 let our_min_secret = self.get_min_seen_secret();
 438                 if our_min_secret > other_min_secret {
 439                         self.provide_secret(other_min_secret, other.get_secret(other_min_secret).unwrap(), None)?;
 440                 }
 441                 if our_min_secret >= other_min_secret {
 442                         self.their_cur_revocation_points = other.their_cur_revocation_points;
 443                         for (txid, htlcs) in other.remote_claimable_outpoints.drain() {
 444                                 self.remote_claimable_outpoints.insert(txid, htlcs);
 445                         }
 446                         if let Some(local_tx) = other.prev_local_signed_commitment_tx {
 447                                 self.prev_local_signed_commitment_tx = Some(local_tx);
 448                         }
 449                         if let Some(local_tx) = other.current_local_signed_commitment_tx {
 450                                 self.current_local_signed_commitment_tx = Some(local_tx);
 451                         }
 452                         self.payment_preimages = other.payment_preimages;
 453                 }
 454                 Ok(())
 455         }
 456
 457         /// Panics if commitment_transaction_number_obscure_factor doesn't fit in 48 bits
 458         pub(super) fn set_commitment_obscure_factor(&mut self, commitment_transaction_number_obscure_factor: u64) {
 459                 assert!(commitment_transaction_number_obscure_factor < (1 << 48));
 460                 self.commitment_transaction_number_obscure_factor = commitment_transaction_number_obscure_factor;
 461         }
 462
 463         /// Allows this monitor to scan only for transactions which are applicable. Note that this is
 464         /// optional, without it this monitor cannot be used in an SPV client, but you may wish to
 465         /// avoid this (or call unset_funding_info) on a monitor you wish to send to a watchtower as it
 466         /// provides slightly better privacy.
 467         pub(super) fn set_funding_info(&mut self, funding_info: (OutPoint, Script)) {
 468                 //TODO: Need to register the given script here with a chain_monitor
 469                 self.funding_txo = Some(funding_info);
 470         }
 471
 472         pub(super) fn set_their_htlc_base_key(&mut self, their_htlc_base_key: &PublicKey) {
 473                 self.their_htlc_base_key = Some(their_htlc_base_key.clone());
 474         }
 475
 476         pub(super) fn set_their_to_self_delay(&mut self, their_to_self_delay: u16) {
 477                 self.their_to_self_delay = Some(their_to_self_delay);
 478         }
 479
 480         pub(super) fn unset_funding_info(&mut self) {
 481                 self.funding_txo = None;
 482         }
 483
 484         pub fn get_funding_txo(&self) -> Option<OutPoint> {
 485                 match self.funding_txo {
 486                         Some((outpoint, _)) => Some(outpoint),
 487                         None => None
 488                 }
 489         }
 490
 491         /// Serializes into a vec, with various modes for the exposed pub fns
 492         fn serialize(&self, for_local_storage: bool) -> Vec<u8> {
 493                 let mut res = Vec::new();
 494                 res.push(SERIALIZATION_VERSION);
 495                 res.push(MIN_SERIALIZATION_VERSION);
 496
 497                 match &self.funding_txo {
 498                         &Some((ref outpoint, ref script)) => {
 499                                 res.extend_from_slice(&outpoint.txid[..]);
 500                                 res.extend_from_slice(&byte_utils::be16_to_array(outpoint.index));
 501                                 res.extend_from_slice(&byte_utils::be64_to_array(script.len() as u64));
 502                                 res.extend_from_slice(&script[..]);
 503                         },
 504                         &None => {
 505                                 // We haven't even been initialized...not sure why anyone is serializing us, but
 506                                 // not much to give them.
 507                                 return res;
 508                         },
 509                 }
 510
 511                 // Set in initial Channel-object creation, so should always be set by now:
 512                 res.extend_from_slice(&byte_utils::be48_to_array(self.commitment_transaction_number_obscure_factor));
 513
 514                 match self.key_storage {
 515                         KeyStorage::PrivMode { ref revocation_base_key, ref htlc_base_key } => {
 516                                 res.push(0);
 517                                 res.extend_from_slice(&revocation_base_key[..]);
 518                                 res.extend_from_slice(&htlc_base_key[..]);
 519                         },
 520                         KeyStorage::SigsMode { .. } => unimplemented!(),
 521                 }
 522
 523                 res.extend_from_slice(&self.delayed_payment_base_key.serialize());
 524                 res.extend_from_slice(&self.their_htlc_base_key.as_ref().unwrap().serialize());
 525
 526                 match self.their_cur_revocation_points {
 527                         Some((idx, pubkey, second_option)) => {
 528                                 res.extend_from_slice(&byte_utils::be48_to_array(idx));
 529                                 res.extend_from_slice(&pubkey.serialize());
 530                                 match second_option {
 531                                         Some(second_pubkey) => {
 532                                                 res.extend_from_slice(&second_pubkey.serialize());
 533                                         },
 534                                         None => {
 535                                                 res.extend_from_slice(&[0; 33]);
 536                                         },
 537                                 }
 538                         },
 539                         None => {
 540                                 res.extend_from_slice(&byte_utils::be48_to_array(0));
 541                         },
 542                 }
 543
 544                 res.extend_from_slice(&byte_utils::be16_to_array(self.our_to_self_delay));
 545                 res.extend_from_slice(&byte_utils::be16_to_array(self.their_to_self_delay.unwrap()));
 546
 547                 for &(ref secret, ref idx) in self.old_secrets.iter() {
 548                         res.extend_from_slice(secret);
 549                         res.extend_from_slice(&byte_utils::be64_to_array(*idx));
 550                 }
 551
 552                 macro_rules! serialize_htlc_in_commitment {
 553                         ($htlc_output: expr) => {
 554                                 res.push($htlc_output.offered as u8);
 555                                 res.extend_from_slice(&byte_utils::be64_to_array($htlc_output.amount_msat));
 556                                 res.extend_from_slice(&byte_utils::be32_to_array($htlc_output.cltv_expiry));
 557                                 res.extend_from_slice(&$htlc_output.payment_hash);
 558                                 res.extend_from_slice(&byte_utils::be32_to_array($htlc_output.transaction_output_index));
 559                         }
 560                 }
 561
 562                 res.extend_from_slice(&byte_utils::be64_to_array(self.remote_claimable_outpoints.len() as u64));
 563                 for (txid, htlc_outputs) in self.remote_claimable_outpoints.iter() {
 564                         res.extend_from_slice(&txid[..]);
 565                         res.extend_from_slice(&byte_utils::be64_to_array(htlc_outputs.len() as u64));
 566                         for htlc_output in htlc_outputs.iter() {
 567                                 serialize_htlc_in_commitment!(htlc_output);
 568                         }
 569                 }
 570
 571                 {
 572                         let remote_commitment_txn_on_chain = self.remote_commitment_txn_on_chain.lock().unwrap();
 573                         res.extend_from_slice(&byte_utils::be64_to_array(remote_commitment_txn_on_chain.len() as u64));
 574                         for (txid, commitment_number) in remote_commitment_txn_on_chain.iter() {
 575                                 res.extend_from_slice(&txid[..]);
 576                                 res.extend_from_slice(&byte_utils::be48_to_array(*commitment_number));
 577                         }
 578                 }
 579
 580                 if for_local_storage {
 581                         res.extend_from_slice(&byte_utils::be64_to_array(self.remote_hash_commitment_number.len() as u64));
 582                         for (payment_hash, commitment_number) in self.remote_hash_commitment_number.iter() {
 583                                 res.extend_from_slice(payment_hash);
 584                                 res.extend_from_slice(&byte_utils::be48_to_array(*commitment_number));
 585                         }
 586                 } else {
 587                         res.extend_from_slice(&byte_utils::be64_to_array(0));
 588                 }
 589
 590                 macro_rules! serialize_local_tx {
 591                         ($local_tx: expr) => {
 592                                 let tx_ser = serialize::serialize(&$local_tx.tx).unwrap();
 593                                 res.extend_from_slice(&byte_utils::be64_to_array(tx_ser.len() as u64));
 594                                 res.extend_from_slice(&tx_ser);
 595
 596                                 res.extend_from_slice(&$local_tx.revocation_key.serialize());
 597                                 res.extend_from_slice(&$local_tx.a_htlc_key.serialize());
 598                                 res.extend_from_slice(&$local_tx.b_htlc_key.serialize());
 599                                 res.extend_from_slice(&$local_tx.delayed_payment_key.serialize());
 600
 601                                 res.extend_from_slice(&byte_utils::be64_to_array($local_tx.feerate_per_kw));
 602                                 res.extend_from_slice(&byte_utils::be64_to_array($local_tx.htlc_outputs.len() as u64));
 603                                 for &(ref htlc_output, ref their_sig, ref our_sig) in $local_tx.htlc_outputs.iter() {
 604                                         serialize_htlc_in_commitment!(htlc_output);
 605                                         res.extend_from_slice(&their_sig.serialize_compact(&self.secp_ctx));
 606                                         res.extend_from_slice(&our_sig.serialize_compact(&self.secp_ctx));
 607                                 }
 608                         }
 609                 }
 610
 611                 if let Some(ref prev_local_tx) = self.prev_local_signed_commitment_tx {
 612                         res.push(1);
 613                         serialize_local_tx!(prev_local_tx);
 614                 } else {
 615                         res.push(0);
 616                 }
 617
 618                 if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
 619                         res.push(1);
 620                         serialize_local_tx!(cur_local_tx);
 621                 } else {
 622                         res.push(0);
 623                 }
 624
 625                 res.extend_from_slice(&byte_utils::be64_to_array(self.payment_preimages.len() as u64));
 626                 for payment_preimage in self.payment_preimages.values() {
 627                         res.extend_from_slice(payment_preimage);
 628                 }
 629
 630                 res.extend_from_slice(&byte_utils::be64_to_array(self.destination_script.len() as u64));
 631                 res.extend_from_slice(&self.destination_script[..]);
 632
 633                 res
 634         }
 635
 636         /// Encodes this monitor into a byte array, suitable for writing to disk.
 637         pub fn serialize_for_disk(&self) -> Vec<u8> {
 638                 self.serialize(true)
 639         }
 640
 641         /// Encodes this monitor into a byte array, suitable for sending to a remote watchtower
 642         pub fn serialize_for_watchtower(&self) -> Vec<u8> {
 643                 self.serialize(false)
 644         }
 645
 646         /// Attempts to decode a serialized monitor
 647         pub fn deserialize(data: &[u8]) -> Option<Self> {
 648                 let mut read_pos = 0;
 649                 macro_rules! read_bytes {
 650                         ($byte_count: expr) => {
 651                                 {
 652                                         if ($byte_count as usize) > data.len() - read_pos {
 653                                                 return None;
 654                                         }
 655                                         read_pos += $byte_count as usize;
 656                                         &data[read_pos - $byte_count as usize..read_pos]
 657                                 }
 658                         }
 659                 }
 660
 661                 let secp_ctx = Secp256k1::new();
 662                 macro_rules! unwrap_obj {
 663                         ($key: expr) => {
 664                                 match $key {
 665                                         Ok(res) => res,
 666                                         Err(_) => return None,
 667                                 }
 668                         }
 669                 }
 670
 671                 let _ver = read_bytes!(1)[0];
 672                 let min_ver = read_bytes!(1)[0];
 673                 if min_ver > SERIALIZATION_VERSION {
 674                         return None;
 675                 }
 676
 677                 // Technically this can fail and serialize fail a round-trip, but only for serialization of
 678                 // barely-init'd ChannelMonitors that we can't do anything with.
 679                 let outpoint = OutPoint {
 680                         txid: Sha256dHash::from(read_bytes!(32)),
 681                         index: byte_utils::slice_to_be16(read_bytes!(2)),
 682                 };
 683                 let script_len = byte_utils::slice_to_be64(read_bytes!(8));
 684                 let funding_txo = Some((outpoint, Script::from(read_bytes!(script_len).to_vec())));
 685                 let commitment_transaction_number_obscure_factor = byte_utils::slice_to_be48(read_bytes!(6));
 686
 687                 let key_storage = match read_bytes!(1)[0] {
 688                         0 => {
 689                                 KeyStorage::PrivMode {
 690                                         revocation_base_key: unwrap_obj!(SecretKey::from_slice(&secp_ctx, read_bytes!(32))),
 691                                         htlc_base_key: unwrap_obj!(SecretKey::from_slice(&secp_ctx, read_bytes!(32))),
 692                                 }
 693                         },
 694                         _ => return None,
 695                 };
 696
 697                 let delayed_payment_base_key = unwrap_obj!(PublicKey::from_slice(&secp_ctx, read_bytes!(33)));
 698                 let their_htlc_base_key = Some(unwrap_obj!(PublicKey::from_slice(&secp_ctx, read_bytes!(33))));
 699
 700                 let their_cur_revocation_points = {
 701                         let first_idx = byte_utils::slice_to_be48(read_bytes!(6));
 702                         if first_idx == 0 {
 703                                 None
 704                         } else {
 705                                 let first_point = unwrap_obj!(PublicKey::from_slice(&secp_ctx, read_bytes!(33)));
 706                                 let second_point_slice = read_bytes!(33);
 707                                 if second_point_slice[0..32] == [0; 32] && second_point_slice[32] == 0 {
 708                                         Some((first_idx, first_point, None))
 709                                 } else {
 710                                         Some((first_idx, first_point, Some(unwrap_obj!(PublicKey::from_slice(&secp_ctx, second_point_slice)))))
 711                                 }
 712                         }
 713                 };
 714
 715                 let our_to_self_delay = byte_utils::slice_to_be16(read_bytes!(2));
 716                 let their_to_self_delay = Some(byte_utils::slice_to_be16(read_bytes!(2)));
 717
 718                 let mut old_secrets = [([0; 32], 1 << 48); 49];
 719                 for &mut (ref mut secret, ref mut idx) in old_secrets.iter_mut() {
 720                         secret.copy_from_slice(read_bytes!(32));
 721                         *idx = byte_utils::slice_to_be64(read_bytes!(8));
 722                 }
 723
 724                 macro_rules! read_htlc_in_commitment {
 725                         () => {
 726                                 {
 727                                         let offered = match read_bytes!(1)[0] {
 728                                                 0 => false, 1 => true,
 729                                                 _ => return None,
 730                                         };
 731                                         let amount_msat = byte_utils::slice_to_be64(read_bytes!(8));
 732                                         let cltv_expiry = byte_utils::slice_to_be32(read_bytes!(4));
 733                                         let mut payment_hash = [0; 32];
 734                                         payment_hash[..].copy_from_slice(read_bytes!(32));
 735                                         let transaction_output_index = byte_utils::slice_to_be32(read_bytes!(4));
 736
 737                                         HTLCOutputInCommitment {
 738                                                 offered, amount_msat, cltv_expiry, payment_hash, transaction_output_index
 739                                         }
 740                                 }
 741                         }
 742                 }
 743
 744                 let remote_claimable_outpoints_len = byte_utils::slice_to_be64(read_bytes!(8));
 745                 if remote_claimable_outpoints_len > data.len() as u64 / 64 { return None; }
 746                 let mut remote_claimable_outpoints = HashMap::with_capacity(remote_claimable_outpoints_len as usize);
 747                 for _ in 0..remote_claimable_outpoints_len {
 748                         let txid = Sha256dHash::from(read_bytes!(32));
 749                         let outputs_count = byte_utils::slice_to_be64(read_bytes!(8));
 750                         if outputs_count > data.len() as u64 / 32 { return None; }
 751                         let mut outputs = Vec::with_capacity(outputs_count as usize);
 752                         for _ in 0..outputs_count {
 753                                 outputs.push(read_htlc_in_commitment!());
 754                         }
 755                         if let Some(_) = remote_claimable_outpoints.insert(txid, outputs) {
 756                                 return None;
 757                         }
 758                 }
 759
 760                 let remote_commitment_txn_on_chain_len = byte_utils::slice_to_be64(read_bytes!(8));
 761                 if remote_commitment_txn_on_chain_len > data.len() as u64 / 32 { return None; }
 762                 let mut remote_commitment_txn_on_chain = HashMap::with_capacity(remote_commitment_txn_on_chain_len as usize);
 763                 for _ in 0..remote_commitment_txn_on_chain_len {
 764                         let txid = Sha256dHash::from(read_bytes!(32));
 765                         let commitment_number = byte_utils::slice_to_be48(read_bytes!(6));
 766                         if let Some(_) = remote_commitment_txn_on_chain.insert(txid, commitment_number) {
 767                                 return None;
 768                         }
 769                 }
 770
 771                 let remote_hash_commitment_number_len = byte_utils::slice_to_be64(read_bytes!(8));
 772                 if remote_hash_commitment_number_len > data.len() as u64 / 32 { return None; }
 773                 let mut remote_hash_commitment_number = HashMap::with_capacity(remote_hash_commitment_number_len as usize);
 774                 for _ in 0..remote_hash_commitment_number_len {
 775                         let mut txid = [0; 32];
 776                         txid[..].copy_from_slice(read_bytes!(32));
 777                         let commitment_number = byte_utils::slice_to_be48(read_bytes!(6));
 778                         if let Some(_) = remote_hash_commitment_number.insert(txid, commitment_number) {
 779                                 return None;
 780                         }
 781                 }
 782
 783                 macro_rules! read_local_tx {
 784                         () => {
 785                                 {
 786                                         let tx_len = byte_utils::slice_to_be64(read_bytes!(8));
 787                                         let tx_ser = read_bytes!(tx_len);
 788                                         let tx: Transaction = unwrap_obj!(serialize::deserialize(tx_ser));
 789                                         if serialize::serialize(&tx).unwrap() != tx_ser {
 790                                                 // We check that the tx re-serializes to the same form to ensure there is
 791                                                 // no extra data, and as rust-bitcoin doesn't handle the 0-input ambiguity
 792                                                 // all that well.
 793                                                 return None;
 794                                         }
 795
 796                                         let revocation_key = unwrap_obj!(PublicKey::from_slice(&secp_ctx, read_bytes!(33)));
 797                                         let a_htlc_key = unwrap_obj!(PublicKey::from_slice(&secp_ctx, read_bytes!(33)));
 798                                         let b_htlc_key = unwrap_obj!(PublicKey::from_slice(&secp_ctx, read_bytes!(33)));
 799                                         let delayed_payment_key = unwrap_obj!(PublicKey::from_slice(&secp_ctx, read_bytes!(33)));
 800                                         let feerate_per_kw = byte_utils::slice_to_be64(read_bytes!(8));
 801
 802                                         let htlc_outputs_len = byte_utils::slice_to_be64(read_bytes!(8));
 803                                         if htlc_outputs_len > data.len() as u64 / 128 { return None; }
 804                                         let mut htlc_outputs = Vec::with_capacity(htlc_outputs_len as usize);
 805                                         for _ in 0..htlc_outputs_len {
 806                                                 htlc_outputs.push((read_htlc_in_commitment!(),
 807                                                                 unwrap_obj!(Signature::from_compact(&secp_ctx, read_bytes!(64))),
 808                                                                 unwrap_obj!(Signature::from_compact(&secp_ctx, read_bytes!(64)))));
 809                                         }
 810
 811                                         LocalSignedTx {
 812                                                 txid: tx.txid(),
 813                                                 tx, revocation_key, a_htlc_key, b_htlc_key, delayed_payment_key, feerate_per_kw, htlc_outputs
 814                                         }
 815                                 }
 816                         }
 817                 }
 818
 819                 let prev_local_signed_commitment_tx = match read_bytes!(1)[0] {
 820                         0 => None,
 821                         1 => {
 822                                 Some(read_local_tx!())
 823                         },
 824                         _ => return None,
 825                 };
 826
 827                 let current_local_signed_commitment_tx = match read_bytes!(1)[0] {
 828                         0 => None,
 829                         1 => {
 830                                 Some(read_local_tx!())
 831                         },
 832                         _ => return None,
 833                 };
 834
 835                 let payment_preimages_len = byte_utils::slice_to_be64(read_bytes!(8));
 836                 if payment_preimages_len > data.len() as u64 / 32 { return None; }
 837                 let mut payment_preimages = HashMap::with_capacity(payment_preimages_len as usize);
 838                 let mut sha = Sha256::new();
 839                 for _ in 0..payment_preimages_len {
 840                         let mut preimage = [0; 32];
 841                         preimage[..].copy_from_slice(read_bytes!(32));
 842                         sha.reset();
 843                         sha.input(&preimage);
 844                         let mut hash = [0; 32];
 845                         sha.result(&mut hash);
 846                         if let Some(_) = payment_preimages.insert(hash, preimage) {
 847                                 return None;
 848                         }
 849                 }
 850
 851                 let destination_script_len = byte_utils::slice_to_be64(read_bytes!(8));
 852                 let destination_script = Script::from(read_bytes!(destination_script_len).to_vec());
 853
 854                 Some(ChannelMonitor {
 855                         funding_txo,
 856                         commitment_transaction_number_obscure_factor,
 857
 858                         key_storage,
 859                         delayed_payment_base_key,
 860                         their_htlc_base_key,
 861                         their_cur_revocation_points,
 862
 863                         our_to_self_delay,
 864                         their_to_self_delay,
 865
 866                         old_secrets,
 867                         remote_claimable_outpoints,
 868                         remote_commitment_txn_on_chain: Mutex::new(remote_commitment_txn_on_chain),
 869                         remote_hash_commitment_number,
 870
 871                         prev_local_signed_commitment_tx,
 872                         current_local_signed_commitment_tx,
 873
 874                         payment_preimages,
 875
 876                         destination_script,
 877                         secp_ctx,
 878                 })
 879         }
 880
 881         //TODO: Functions to serialize/deserialize (with different forms depending on which information
 882         //we want to leave out (eg funding_txo, etc).
 883
 884         /// Can only fail if idx is < get_min_seen_secret
 885         pub fn get_secret(&self, idx: u64) -> Result<[u8; 32], HandleError> {
 886                 for i in 0..self.old_secrets.len() {
 887                         if (idx & (!((1 << i) - 1))) == self.old_secrets[i].1 {
 888                                 return Ok(ChannelMonitor::derive_secret(self.old_secrets[i].0, i as u8, idx))
 889                         }
 890                 }
 891                 assert!(idx < self.get_min_seen_secret());
 892                 Err(HandleError{err: "idx too low", action: None})
 893         }
 894
 895         pub fn get_min_seen_secret(&self) -> u64 {
 896                 //TODO This can be optimized?
 897                 let mut min = 1 << 48;
 898                 for &(_, idx) in self.old_secrets.iter() {
 899                         if idx < min {
 900                                 min = idx;
 901                         }
 902                 }
 903                 min
 904         }
 905
 906         /// Attempts to claim a remote commitment transaction's outputs using the revocation key and
 907         /// data in remote_claimable_outpoints. Will directly claim any HTLC outputs which expire at a
 908         /// height > height + CLTV_SHARED_CLAIM_BUFFER. In any case, will install monitoring for
 909         /// HTLC-Success/HTLC-Timeout transactions, and claim them using the revocation key (if
 910         /// applicable) as well.
 911         fn check_spend_remote_transaction(&self, tx: &Transaction, height: u32) -> Vec<Transaction> {
 912                 // Most secp and related errors trying to create keys means we have no hope of constructing
 913                 // a spend transaction...so we return no transactions to broadcast
 914                 let mut txn_to_broadcast = Vec::new();
 915                 macro_rules! ignore_error {
 916                         ( $thing : expr ) => {
 917                                 match $thing {
 918                                         Ok(a) => a,
 919                                         Err(_) => return txn_to_broadcast
 920                                 }
 921                         };
 922                 }
 923
 924                 let commitment_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
 925                 let per_commitment_option = self.remote_claimable_outpoints.get(&commitment_txid);
 926
 927                 let commitment_number = 0xffffffffffff - ((((tx.input[0].sequence as u64 & 0xffffff) << 3*8) | (tx.lock_time as u64 & 0xffffff)) ^ self.commitment_transaction_number_obscure_factor);
 928                 if commitment_number >= self.get_min_seen_secret() {
 929                         let secret = self.get_secret(commitment_number).unwrap();
 930                         let per_commitment_key = ignore_error!(SecretKey::from_slice(&self.secp_ctx, &secret));
 931                         let (revocation_pubkey, b_htlc_key) = match self.key_storage {
 932                                 KeyStorage::PrivMode { ref revocation_base_key, ref htlc_base_key } => {
 933                                         let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
 934                                         (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &PublicKey::from_secret_key(&self.secp_ctx, &revocation_base_key))),
 935                                         ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &PublicKey::from_secret_key(&self.secp_ctx, &htlc_base_key))))
 936                                 },
 937                                 KeyStorage::SigsMode { ref revocation_base_key, ref htlc_base_key, .. } => {
 938                                         let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
 939                                         (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &revocation_base_key)),
 940                                         ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &htlc_base_key)))
 941                                 },
 942                         };
 943                         let delayed_key = ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key), &self.delayed_payment_base_key));
 944                         let a_htlc_key = match self.their_htlc_base_key {
 945                                 None => return txn_to_broadcast,
 946                                 Some(their_htlc_base_key) => ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key), &their_htlc_base_key)),
 947                         };
 948
 949                         let revokeable_redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.our_to_self_delay, &delayed_key);
 950                         let revokeable_p2wsh = revokeable_redeemscript.to_v0_p2wsh();
 951
 952                         let mut total_value = 0;
 953                         let mut values = Vec::new();
 954                         let mut inputs = Vec::new();
 955                         let mut htlc_idxs = Vec::new();
 956
 957                         for (idx, outp) in tx.output.iter().enumerate() {
 958                                 if outp.script_pubkey == revokeable_p2wsh {
 959                                         inputs.push(TxIn {
 960                                                 previous_output: BitcoinOutPoint {
 961                                                         txid: commitment_txid,
 962                                                         vout: idx as u32,
 963                                                 },
 964                                                 script_sig: Script::new(),
 965                                                 sequence: 0xfffffffd,
 966                                                 witness: Vec::new(),
 967                                         });
 968                                         htlc_idxs.push(None);
 969                                         values.push(outp.value);
 970                                         total_value += outp.value;
 971                                         break; // There can only be one of these
 972                                 }
 973                         }
 974
 975                         macro_rules! sign_input {
 976                                 ($sighash_parts: expr, $input: expr, $htlc_idx: expr, $amount: expr) => {
 977                                         {
 978                                                 let (sig, redeemscript) = match self.key_storage {
 979                                                         KeyStorage::PrivMode { ref revocation_base_key, .. } => {
 980                                                                 let redeemscript = if $htlc_idx.is_none() { revokeable_redeemscript.clone() } else {
 981                                                                         let htlc = &per_commitment_option.unwrap()[$htlc_idx.unwrap()];
 982                                                                         chan_utils::get_htlc_redeemscript_with_explicit_keys(htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey)
 983                                                                 };
 984                                                                 let sighash = ignore_error!(Message::from_slice(&$sighash_parts.sighash_all(&$input, &redeemscript, $amount)[..]));
 985                                                                 let revocation_key = ignore_error!(chan_utils::derive_private_revocation_key(&self.secp_ctx, &per_commitment_key, &revocation_base_key));
 986                                                                 (self.secp_ctx.sign(&sighash, &revocation_key), redeemscript)
 987                                                         },
 988                                                         KeyStorage::SigsMode { .. } => {
 989                                                                 unimplemented!();
 990                                                         }
 991                                                 };
 992                                                 $input.witness.push(sig.serialize_der(&self.secp_ctx).to_vec());
 993                                                 $input.witness[0].push(SigHashType::All as u8);
 994                                                 if $htlc_idx.is_none() {
 995                                                         $input.witness.push(vec!(1));
 996                                                 } else {
 997                                                         $input.witness.push(revocation_pubkey.serialize().to_vec());
 998                                                 }
 999                                                 $input.witness.push(redeemscript.into_bytes());
1000                                         }
1001                                 }
1002                         }
1003
1004                         if let Some(per_commitment_data) = per_commitment_option {
1005                                 inputs.reserve_exact(per_commitment_data.len());
1006
1007                                 for (idx, htlc) in per_commitment_data.iter().enumerate() {
1008                                         let expected_script = chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey);
1009                                         if htlc.transaction_output_index as usize >= tx.output.len() ||
1010                                                         tx.output[htlc.transaction_output_index as usize].value != htlc.amount_msat / 1000 ||
1011                                                         tx.output[htlc.transaction_output_index as usize].script_pubkey != expected_script.to_v0_p2wsh() {
1012                                                 return txn_to_broadcast; // Corrupted per_commitment_data, fuck this user
1013                                         }
1014                                         let input = TxIn {
1015                                                 previous_output: BitcoinOutPoint {
1016                                                         txid: commitment_txid,
1017                                                         vout: htlc.transaction_output_index,
1018                                                 },
1019                                                 script_sig: Script::new(),
1020                                                 sequence: 0xfffffffd,
1021                                                 witness: Vec::new(),
1022                                         };
1023                                         if htlc.cltv_expiry > height + CLTV_SHARED_CLAIM_BUFFER {
1024                                                 inputs.push(input);
1025                                                 htlc_idxs.push(Some(idx));
1026                                                 values.push(tx.output[htlc.transaction_output_index as usize].value);
1027                                                 total_value += htlc.amount_msat / 1000;
1028                                         } else {
1029                                                 let mut single_htlc_tx = Transaction {
1030                                                         version: 2,
1031                                                         lock_time: 0,
1032                                                         input: vec![input],
1033                                                         output: vec!(TxOut {
1034                                                                 script_pubkey: self.destination_script.clone(),
1035                                                                 value: htlc.amount_msat / 1000, //TODO: - fee
1036                                                         }),
1037                                                 };
1038                                                 let sighash_parts = bip143::SighashComponents::new(&single_htlc_tx);
1039                                                 sign_input!(sighash_parts, single_htlc_tx.input[0], Some(idx), htlc.amount_msat / 1000);
1040                                                 txn_to_broadcast.push(single_htlc_tx); // TODO: This is not yet tested in ChannelManager!
1041                                         }
1042                                 }
1043                         }
1044
1045                         if !inputs.is_empty() || !txn_to_broadcast.is_empty() { // ie we're confident this is actually ours
1046                                 // We're definitely a remote commitment transaction!
1047                                 // TODO: Register all outputs in commitment_tx with the ChainWatchInterface!
1048                                 self.remote_commitment_txn_on_chain.lock().unwrap().insert(commitment_txid, commitment_number);
1049                         }
1050                         if inputs.is_empty() { return txn_to_broadcast; } // Nothing to be done...probably a false positive/local tx
1051
1052                         let outputs = vec!(TxOut {
1053                                 script_pubkey: self.destination_script.clone(),
1054                                 value: total_value, //TODO: - fee
1055                         });
1056                         let mut spend_tx = Transaction {
1057                                 version: 2,
1058                                 lock_time: 0,
1059                                 input: inputs,
1060                                 output: outputs,
1061                         };
1062
1063                         let mut values_drain = values.drain(..);
1064                         let sighash_parts = bip143::SighashComponents::new(&spend_tx);
1065
1066                         for (input, htlc_idx) in spend_tx.input.iter_mut().zip(htlc_idxs.iter()) {
1067                                 let value = values_drain.next().unwrap();
1068                                 sign_input!(sighash_parts, input, htlc_idx, value);
1069                         }
1070
1071                         txn_to_broadcast.push(spend_tx);
1072                 } else if let Some(per_commitment_data) = per_commitment_option {
1073                         // While this isn't useful yet, there is a potential race where if a counterparty
1074                         // revokes a state at the same time as the commitment transaction for that state is
1075                         // confirmed, and the watchtower receives the block before the user, the user could
1076                         // upload a new ChannelMonitor with the revocation secret but the watchtower has
1077                         // already processed the block, resulting in the remote_commitment_txn_on_chain entry
1078                         // not being generated by the above conditional. Thus, to be safe, we go ahead and
1079                         // insert it here.
1080                         // TODO: Register all outputs in commitment_tx with the ChainWatchInterface!
1081                         self.remote_commitment_txn_on_chain.lock().unwrap().insert(commitment_txid, commitment_number);
1082
1083                         if let Some(revocation_points) = self.their_cur_revocation_points {
1084                                 let revocation_point_option =
1085                                         if revocation_points.0 == commitment_number { Some(&revocation_points.1) }
1086                                         else if let Some(point) = revocation_points.2.as_ref() {
1087                                                 if revocation_points.0 == commitment_number + 1 { Some(point) } else { None }
1088                                         } else { None };
1089                                 if let Some(revocation_point) = revocation_point_option {
1090                                         let (revocation_pubkey, b_htlc_key) = match self.key_storage {
1091                                                 KeyStorage::PrivMode { ref revocation_base_key, ref htlc_base_key } => {
1092                                                         (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, revocation_point, &PublicKey::from_secret_key(&self.secp_ctx, &revocation_base_key))),
1093                                                         ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &PublicKey::from_secret_key(&self.secp_ctx, &htlc_base_key))))
1094                                                 },
1095                                                 KeyStorage::SigsMode { ref revocation_base_key, ref htlc_base_key, .. } => {
1096                                                         (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, revocation_point, &revocation_base_key)),
1097                                                         ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &htlc_base_key)))
1098                                                 },
1099                                         };
1100                                         let a_htlc_key = match self.their_htlc_base_key {
1101                                                 None => return txn_to_broadcast,
1102                                                 Some(their_htlc_base_key) => ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &their_htlc_base_key)),
1103                                         };
1104
1105                                         let mut total_value = 0;
1106                                         let mut values = Vec::new();
1107                                         let mut inputs = Vec::new();
1108
1109                                         macro_rules! sign_input {
1110                                                 ($sighash_parts: expr, $input: expr, $amount: expr, $preimage: expr) => {
1111                                                         {
1112                                                                 let (sig, redeemscript) = match self.key_storage {
1113                                                                         KeyStorage::PrivMode { ref htlc_base_key, .. } => {
1114                                                                                 let htlc = &per_commitment_option.unwrap()[$input.sequence as usize];
1115                                                                                 let redeemscript = chan_utils::get_htlc_redeemscript_with_explicit_keys(htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey);
1116                                                                                 let sighash = ignore_error!(Message::from_slice(&$sighash_parts.sighash_all(&$input, &redeemscript, $amount)[..]));
1117                                                                                 let htlc_key = ignore_error!(chan_utils::derive_private_key(&self.secp_ctx, revocation_point, &htlc_base_key));
1118                                                                                 (self.secp_ctx.sign(&sighash, &htlc_key), redeemscript)
1119                                                                         },
1120                                                                         KeyStorage::SigsMode { .. } => {
1121                                                                                 unimplemented!();
1122                                                                         }
1123                                                                 };
1124                                                                 $input.witness.push(sig.serialize_der(&self.secp_ctx).to_vec());
1125                                                                 $input.witness[0].push(SigHashType::All as u8);
1126                                                                 $input.witness.push($preimage);
1127                                                                 $input.witness.push(redeemscript.into_bytes());
1128                                                         }
1129                                                 }
1130                                         }
1131
1132                                         for (idx, htlc) in per_commitment_data.iter().enumerate() {
1133                                                 if let Some(payment_preimage) = self.payment_preimages.get(&htlc.payment_hash) {
1134                                                         let input = TxIn {
1135                                                                 previous_output: BitcoinOutPoint {
1136                                                                         txid: commitment_txid,
1137                                                                         vout: htlc.transaction_output_index,
1138                                                                 },
1139                                                                 script_sig: Script::new(),
1140                                                                 sequence: idx as u32, // reset to 0xfffffffd in sign_input
1141                                                                 witness: Vec::new(),
1142                                                         };
1143                                                         if htlc.cltv_expiry > height + CLTV_SHARED_CLAIM_BUFFER {
1144                                                                 inputs.push(input);
1145                                                                 values.push((tx.output[htlc.transaction_output_index as usize].value, payment_preimage));
1146                                                                 total_value += htlc.amount_msat / 1000;
1147                                                         } else {
1148                                                                 let mut single_htlc_tx = Transaction {
1149                                                                         version: 2,
1150                                                                         lock_time: 0,
1151                                                                         input: vec![input],
1152                                                                         output: vec!(TxOut {
1153                                                                                 script_pubkey: self.destination_script.clone(),
1154                                                                                 value: htlc.amount_msat / 1000, //TODO: - fee
1155                                                                         }),
1156                                                                 };
1157                                                                 let sighash_parts = bip143::SighashComponents::new(&single_htlc_tx);
1158                                                                 sign_input!(sighash_parts, single_htlc_tx.input[0], htlc.amount_msat / 1000, payment_preimage.to_vec());
1159                                                                 txn_to_broadcast.push(single_htlc_tx);
1160                                                         }
1161                                                 }
1162                                         }
1163
1164                                         if inputs.is_empty() { return txn_to_broadcast; } // Nothing to be done...probably a false positive/local tx
1165
1166                                         let outputs = vec!(TxOut {
1167                                                 script_pubkey: self.destination_script.clone(),
1168                                                 value: total_value, //TODO: - fee
1169                                         });
1170                                         let mut spend_tx = Transaction {
1171                                                 version: 2,
1172                                                 lock_time: 0,
1173                                                 input: inputs,
1174                                                 output: outputs,
1175                                         };
1176
1177                                         let mut values_drain = values.drain(..);
1178                                         let sighash_parts = bip143::SighashComponents::new(&spend_tx);
1179
1180                                         for input in spend_tx.input.iter_mut() {
1181                                                 let value = values_drain.next().unwrap();
1182                                                 sign_input!(sighash_parts, input, value.0, value.1.to_vec());
1183                                         }
1184
1185                                         txn_to_broadcast.push(spend_tx);
1186                                 }
1187                         }
1188                 } else {
1189                         //TODO: For each input check if its in our remote_commitment_txn_on_chain map!
1190                 }
1191
1192                 txn_to_broadcast
1193         }
1194
1195         fn broadcast_by_local_state(&self, local_tx: &LocalSignedTx) -> Vec<Transaction> {
1196                 let mut res = Vec::with_capacity(local_tx.htlc_outputs.len());
1197
1198                 for &(ref htlc, ref their_sig, ref our_sig) in local_tx.htlc_outputs.iter() {
1199                         if htlc.offered {
1200                                 let mut htlc_timeout_tx = chan_utils::build_htlc_transaction(&local_tx.txid, local_tx.feerate_per_kw, self.their_to_self_delay.unwrap(), htlc, &local_tx.delayed_payment_key, &local_tx.revocation_key);
1201
1202                                 htlc_timeout_tx.input[0].witness.push(Vec::new()); // First is the multisig dummy
1203
1204                                 htlc_timeout_tx.input[0].witness.push(their_sig.serialize_der(&self.secp_ctx).to_vec());
1205                                 htlc_timeout_tx.input[0].witness[1].push(SigHashType::All as u8);
1206                                 htlc_timeout_tx.input[0].witness.push(our_sig.serialize_der(&self.secp_ctx).to_vec());
1207                                 htlc_timeout_tx.input[0].witness[2].push(SigHashType::All as u8);
1208
1209                                 htlc_timeout_tx.input[0].witness.push(Vec::new());
1210                                 htlc_timeout_tx.input[0].witness.push(chan_utils::get_htlc_redeemscript_with_explicit_keys(htlc, &local_tx.a_htlc_key, &local_tx.b_htlc_key, &local_tx.revocation_key).into_bytes());
1211
1212                                 res.push(htlc_timeout_tx);
1213                         } else {
1214                                 if let Some(payment_preimage) = self.payment_preimages.get(&htlc.payment_hash) {
1215                                         let mut htlc_success_tx = chan_utils::build_htlc_transaction(&local_tx.txid, local_tx.feerate_per_kw, self.their_to_self_delay.unwrap(), htlc, &local_tx.delayed_payment_key, &local_tx.revocation_key);
1216
1217                                         htlc_success_tx.input[0].witness.push(Vec::new()); // First is the multisig dummy
1218
1219                                         htlc_success_tx.input[0].witness.push(their_sig.serialize_der(&self.secp_ctx).to_vec());
1220                                         htlc_success_tx.input[0].witness[1].push(SigHashType::All as u8);
1221                                         htlc_success_tx.input[0].witness.push(our_sig.serialize_der(&self.secp_ctx).to_vec());
1222                                         htlc_success_tx.input[0].witness[2].push(SigHashType::All as u8);
1223
1224                                         htlc_success_tx.input[0].witness.push(payment_preimage.to_vec());
1225                                         htlc_success_tx.input[0].witness.push(chan_utils::get_htlc_redeemscript_with_explicit_keys(htlc, &local_tx.a_htlc_key, &local_tx.b_htlc_key, &local_tx.revocation_key).into_bytes());
1226
1227                                         res.push(htlc_success_tx);
1228                                 }
1229                         }
1230                 }
1231
1232                 res
1233         }
1234
1235         /// Attempts to claim any claimable HTLCs in a commitment transaction which was not (yet)
1236         /// revoked using data in local_claimable_outpoints.
1237         /// Should not be used if check_spend_revoked_transaction succeeds.
1238         fn check_spend_local_transaction(&self, tx: &Transaction, _height: u32) -> Vec<Transaction> {
1239                 let commitment_txid = tx.txid();
1240                 if let &Some(ref local_tx) = &self.current_local_signed_commitment_tx {
1241                         if local_tx.txid == commitment_txid {
1242                                 return self.broadcast_by_local_state(local_tx);
1243                         }
1244                 }
1245                 if let &Some(ref local_tx) = &self.prev_local_signed_commitment_tx {
1246                         if local_tx.txid == commitment_txid {
1247                                 return self.broadcast_by_local_state(local_tx);
1248                         }
1249                 }
1250                 Vec::new()
1251         }
1252
1253         fn block_connected(&self, txn_matched: &[&Transaction], height: u32, broadcaster: &BroadcasterInterface) {
1254                 for tx in txn_matched {
1255                         for txin in tx.input.iter() {
1256                                 if self.funding_txo.is_none() || (txin.previous_output.txid == self.funding_txo.as_ref().unwrap().0.txid && txin.previous_output.vout == self.funding_txo.as_ref().unwrap().0.index as u32) {
1257                                         let mut txn = self.check_spend_remote_transaction(tx, height);
1258                                         if txn.is_empty() {
1259                                                 txn = self.check_spend_local_transaction(tx, height);
1260                                         }
1261                                         for tx in txn.iter() {
1262                                                 broadcaster.broadcast_transaction(tx);
1263                                         }
1264                                 }
1265                         }
1266                 }
1267                 if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
1268                         let mut needs_broadcast = false;
1269                         for &(ref htlc, _, _) in cur_local_tx.htlc_outputs.iter() {
1270                                 if htlc.cltv_expiry <= height + CLTV_CLAIM_BUFFER {
1271                                         if htlc.offered || self.payment_preimages.contains_key(&htlc.payment_hash) {
1272                                                 needs_broadcast = true;
1273                                         }
1274                                 }
1275                         }
1276
1277                         if needs_broadcast {
1278                                 broadcaster.broadcast_transaction(&cur_local_tx.tx);
1279                                 for tx in self.broadcast_by_local_state(&cur_local_tx) {
1280                                         broadcaster.broadcast_transaction(&tx);
1281                                 }
1282                         }
1283                 }
1284         }
1285
1286         pub fn would_broadcast_at_height(&self, height: u32) -> bool {
1287                 if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
1288                         for &(ref htlc, _, _) in cur_local_tx.htlc_outputs.iter() {
1289                                 if htlc.cltv_expiry <= height + CLTV_CLAIM_BUFFER {
1290                                         if htlc.offered || self.payment_preimages.contains_key(&htlc.payment_hash) {
1291                                                 return true;
1292                                         }
1293                                 }
1294                         }
1295                 }
1296                 false
1297         }
1298 }
1299
1300 #[cfg(test)]
1301 mod tests {
1302         use bitcoin::blockdata::script::Script;
1303         use bitcoin::blockdata::transaction::Transaction;
1304         use crypto::digest::Digest;
1305         use hex;
1306         use ln::channelmonitor::ChannelMonitor;
1307         use ln::chan_utils::{HTLCOutputInCommitment, TxCreationKeys};
1308         use util::sha2::Sha256;
1309         use secp256k1::key::{SecretKey,PublicKey};
1310         use secp256k1::{Secp256k1, Signature};
1311         use rand::{thread_rng,Rng};
1312
1313         #[test]
1314         fn test_per_commitment_storage() {
1315                 // Test vectors from BOLT 3:
1316                 let mut secrets: Vec<[u8; 32]> = Vec::new();
1317                 let mut monitor: ChannelMonitor;
1318                 let secp_ctx = Secp256k1::new();
1319
1320                 macro_rules! test_secrets {
1321                         () => {
1322                                 let mut idx = 281474976710655;
1323                                 for secret in secrets.iter() {
1324                                         assert_eq!(monitor.get_secret(idx).unwrap(), *secret);
1325                                         idx -= 1;
1326                                 }
1327                                 assert_eq!(monitor.get_min_seen_secret(), idx + 1);
1328                                 assert!(monitor.get_secret(idx).is_err());
1329                         };
1330                 }
1331
1332                 let delayed_payment_base_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap());
1333
1334                 {
1335                         // insert_secret correct sequence
1336                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &delayed_payment_base_key, &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), 0, Script::new());
1337                         secrets.clear();
1338
1339                         secrets.push([0; 32]);
1340                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1341                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone(), None).unwrap();
1342                         test_secrets!();
1343
1344                         secrets.push([0; 32]);
1345                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1346                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone(), None).unwrap();
1347                         test_secrets!();
1348
1349                         secrets.push([0; 32]);
1350                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1351                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone(), None).unwrap();
1352                         test_secrets!();
1353
1354                         secrets.push([0; 32]);
1355                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1356                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone(), None).unwrap();
1357                         test_secrets!();
1358
1359                         secrets.push([0; 32]);
1360                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
1361                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone(), None).unwrap();
1362                         test_secrets!();
1363
1364                         secrets.push([0; 32]);
1365                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
1366                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone(), None).unwrap();
1367                         test_secrets!();
1368
1369                         secrets.push([0; 32]);
1370                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
1371                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone(), None).unwrap();
1372                         test_secrets!();
1373
1374                         secrets.push([0; 32]);
1375                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
1376                         monitor.provide_secret(281474976710648, secrets.last().unwrap().clone(), None).unwrap();
1377                         test_secrets!();
1378                 }
1379
1380                 {
1381                         // insert_secret #1 incorrect
1382                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &delayed_payment_base_key, &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), 0, Script::new());
1383                         secrets.clear();
1384
1385                         secrets.push([0; 32]);
1386                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
1387                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone(), None).unwrap();
1388                         test_secrets!();
1389
1390                         secrets.push([0; 32]);
1391                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1392                         assert_eq!(monitor.provide_secret(281474976710654, secrets.last().unwrap().clone(), None).unwrap_err().err,
1393                                         "Previous secret did not match new one");
1394                 }
1395
1396                 {
1397                         // insert_secret #2 incorrect (#1 derived from incorrect)
1398                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &delayed_payment_base_key, &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), 0, Script::new());
1399                         secrets.clear();
1400
1401                         secrets.push([0; 32]);
1402                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
1403                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone(), None).unwrap();
1404                         test_secrets!();
1405
1406                         secrets.push([0; 32]);
1407                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("dddc3a8d14fddf2b68fa8c7fbad2748274937479dd0f8930d5ebb4ab6bd866a3").unwrap());
1408                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone(), None).unwrap();
1409                         test_secrets!();
1410
1411                         secrets.push([0; 32]);
1412                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1413                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone(), None).unwrap();
1414                         test_secrets!();
1415
1416                         secrets.push([0; 32]);
1417                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1418                         assert_eq!(monitor.provide_secret(281474976710652, secrets.last().unwrap().clone(), None).unwrap_err().err,
1419                                         "Previous secret did not match new one");
1420                 }
1421
1422                 {
1423                         // insert_secret #3 incorrect
1424                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &delayed_payment_base_key, &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), 0, Script::new());
1425                         secrets.clear();
1426
1427                         secrets.push([0; 32]);
1428                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1429                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone(), None).unwrap();
1430                         test_secrets!();
1431
1432                         secrets.push([0; 32]);
1433                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1434                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone(), None).unwrap();
1435                         test_secrets!();
1436
1437                         secrets.push([0; 32]);
1438                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c51a18b13e8527e579ec56365482c62f180b7d5760b46e9477dae59e87ed423a").unwrap());
1439                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone(), None).unwrap();
1440                         test_secrets!();
1441
1442                         secrets.push([0; 32]);
1443                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1444                         assert_eq!(monitor.provide_secret(281474976710652, secrets.last().unwrap().clone(), None).unwrap_err().err,
1445                                         "Previous secret did not match new one");
1446                 }
1447
1448                 {
1449                         // insert_secret #4 incorrect (1,2,3 derived from incorrect)
1450                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &delayed_payment_base_key, &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), 0, Script::new());
1451                         secrets.clear();
1452
1453                         secrets.push([0; 32]);
1454                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
1455                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone(), None).unwrap();
1456                         test_secrets!();
1457
1458                         secrets.push([0; 32]);
1459                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("dddc3a8d14fddf2b68fa8c7fbad2748274937479dd0f8930d5ebb4ab6bd866a3").unwrap());
1460                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone(), None).unwrap();
1461                         test_secrets!();
1462
1463                         secrets.push([0; 32]);
1464                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c51a18b13e8527e579ec56365482c62f180b7d5760b46e9477dae59e87ed423a").unwrap());
1465                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone(), None).unwrap();
1466                         test_secrets!();
1467
1468                         secrets.push([0; 32]);
1469                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("ba65d7b0ef55a3ba300d4e87af29868f394f8f138d78a7011669c79b37b936f4").unwrap());
1470                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone(), None).unwrap();
1471                         test_secrets!();
1472
1473                         secrets.push([0; 32]);
1474                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
1475                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone(), None).unwrap();
1476                         test_secrets!();
1477
1478                         secrets.push([0; 32]);
1479                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
1480                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone(), None).unwrap();
1481                         test_secrets!();
1482
1483                         secrets.push([0; 32]);
1484                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
1485                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone(), None).unwrap();
1486                         test_secrets!();
1487
1488                         secrets.push([0; 32]);
1489                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
1490                         assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone(), None).unwrap_err().err,
1491                                         "Previous secret did not match new one");
1492                 }
1493
1494                 {
1495                         // insert_secret #5 incorrect
1496                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &delayed_payment_base_key, &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), 0, Script::new());
1497                         secrets.clear();
1498
1499                         secrets.push([0; 32]);
1500                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1501                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone(), None).unwrap();
1502                         test_secrets!();
1503
1504                         secrets.push([0; 32]);
1505                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1506                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone(), None).unwrap();
1507                         test_secrets!();
1508
1509                         secrets.push([0; 32]);
1510                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1511                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone(), None).unwrap();
1512                         test_secrets!();
1513
1514                         secrets.push([0; 32]);
1515                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1516                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone(), None).unwrap();
1517                         test_secrets!();
1518
1519                         secrets.push([0; 32]);
1520                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("631373ad5f9ef654bb3dade742d09504c567edd24320d2fcd68e3cc47e2ff6a6").unwrap());
1521                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone(), None).unwrap();
1522                         test_secrets!();
1523
1524                         secrets.push([0; 32]);
1525                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
1526                         assert_eq!(monitor.provide_secret(281474976710650, secrets.last().unwrap().clone(), None).unwrap_err().err,
1527                                         "Previous secret did not match new one");
1528                 }
1529
1530                 {
1531                         // insert_secret #6 incorrect (5 derived from incorrect)
1532                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &delayed_payment_base_key, &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), 0, Script::new());
1533                         secrets.clear();
1534
1535                         secrets.push([0; 32]);
1536                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1537                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone(), None).unwrap();
1538                         test_secrets!();
1539
1540                         secrets.push([0; 32]);
1541                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1542                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone(), None).unwrap();
1543                         test_secrets!();
1544
1545                         secrets.push([0; 32]);
1546                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1547                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone(), None).unwrap();
1548                         test_secrets!();
1549
1550                         secrets.push([0; 32]);
1551                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1552                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone(), None).unwrap();
1553                         test_secrets!();
1554
1555                         secrets.push([0; 32]);
1556                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("631373ad5f9ef654bb3dade742d09504c567edd24320d2fcd68e3cc47e2ff6a6").unwrap());
1557                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone(), None).unwrap();
1558                         test_secrets!();
1559
1560                         secrets.push([0; 32]);
1561                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("b7e76a83668bde38b373970155c868a653304308f9896692f904a23731224bb1").unwrap());
1562                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone(), None).unwrap();
1563                         test_secrets!();
1564
1565                         secrets.push([0; 32]);
1566                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
1567                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone(), None).unwrap();
1568                         test_secrets!();
1569
1570                         secrets.push([0; 32]);
1571                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
1572                         assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone(), None).unwrap_err().err,
1573                                         "Previous secret did not match new one");
1574                 }
1575
1576                 {
1577                         // insert_secret #7 incorrect
1578                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &delayed_payment_base_key, &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), 0, Script::new());
1579                         secrets.clear();
1580
1581                         secrets.push([0; 32]);
1582                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1583                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone(), None).unwrap();
1584                         test_secrets!();
1585
1586                         secrets.push([0; 32]);
1587                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1588                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone(), None).unwrap();
1589                         test_secrets!();
1590
1591                         secrets.push([0; 32]);
1592                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1593                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone(), None).unwrap();
1594                         test_secrets!();
1595
1596                         secrets.push([0; 32]);
1597                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1598                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone(), None).unwrap();
1599                         test_secrets!();
1600
1601                         secrets.push([0; 32]);
1602                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
1603                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone(), None).unwrap();
1604                         test_secrets!();
1605
1606                         secrets.push([0; 32]);
1607                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
1608                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone(), None).unwrap();
1609                         test_secrets!();
1610
1611                         secrets.push([0; 32]);
1612                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("e7971de736e01da8ed58b94c2fc216cb1dca9e326f3a96e7194fe8ea8af6c0a3").unwrap());
1613                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone(), None).unwrap();
1614                         test_secrets!();
1615
1616                         secrets.push([0; 32]);
1617                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
1618                         assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone(), None).unwrap_err().err,
1619                                         "Previous secret did not match new one");
1620                 }
1621
1622                 {
1623                         // insert_secret #8 incorrect
1624                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &delayed_payment_base_key, &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), 0, Script::new());
1625                         secrets.clear();
1626
1627                         secrets.push([0; 32]);
1628                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1629                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone(), None).unwrap();
1630                         test_secrets!();
1631
1632                         secrets.push([0; 32]);
1633                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1634                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone(), None).unwrap();
1635                         test_secrets!();
1636
1637                         secrets.push([0; 32]);
1638                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1639                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone(), None).unwrap();
1640                         test_secrets!();
1641
1642                         secrets.push([0; 32]);
1643                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1644                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone(), None).unwrap();
1645                         test_secrets!();
1646
1647                         secrets.push([0; 32]);
1648                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
1649                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone(), None).unwrap();
1650                         test_secrets!();
1651
1652                         secrets.push([0; 32]);
1653                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
1654                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone(), None).unwrap();
1655                         test_secrets!();
1656
1657                         secrets.push([0; 32]);
1658                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
1659                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone(), None).unwrap();
1660                         test_secrets!();
1661
1662                         secrets.push([0; 32]);
1663                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a7efbc61aac46d34f77778bac22c8a20c6a46ca460addc49009bda875ec88fa4").unwrap());
1664                         assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone(), None).unwrap_err().err,
1665                                         "Previous secret did not match new one");
1666                 }
1667         }
1668
1669         #[test]
1670         fn test_prune_preimages() {
1671                 let secp_ctx = Secp256k1::new();
1672                 let dummy_sig = Signature::from_der(&secp_ctx, &hex::decode("3045022100fa86fa9a36a8cd6a7bb8f06a541787d51371d067951a9461d5404de6b928782e02201c8b7c334c10aed8976a3a465be9a28abff4cb23acbf00022295b378ce1fa3cd").unwrap()[..]).unwrap();
1673
1674                 macro_rules! dummy_keys {
1675                         () => {
1676                                 {
1677                                         let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap());
1678                                         TxCreationKeys {
1679                                                 per_commitment_point: dummy_key.clone(),
1680                                                 revocation_key: dummy_key.clone(),
1681                                                 a_htlc_key: dummy_key.clone(),
1682                                                 b_htlc_key: dummy_key.clone(),
1683                                                 a_delayed_payment_key: dummy_key.clone(),
1684                                                 b_payment_key: dummy_key.clone(),
1685                                         }
1686                                 }
1687                         }
1688                 }
1689                 let dummy_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
1690
1691                 let mut preimages = Vec::new();
1692                 {
1693                         let mut rng  = thread_rng();
1694                         for _ in 0..20 {
1695                                 let mut preimage = [0; 32];
1696                                 rng.fill_bytes(&mut preimage);
1697                                 let mut sha = Sha256::new();
1698                                 sha.input(&preimage);
1699                                 let mut hash = [0; 32];
1700                                 sha.result(&mut hash);
1701                                 preimages.push((preimage, hash));
1702                         }
1703                 }
1704
1705                 macro_rules! preimages_slice_to_htlc_outputs {
1706                         ($preimages_slice: expr) => {
1707                                 {
1708                                         let mut res = Vec::new();
1709                                         for (idx, preimage) in $preimages_slice.iter().enumerate() {
1710                                                 res.push(HTLCOutputInCommitment {
1711                                                         offered: true,
1712                                                         amount_msat: 0,
1713                                                         cltv_expiry: 0,
1714                                                         payment_hash: preimage.1.clone(),
1715                                                         transaction_output_index: idx as u32,
1716                                                 });
1717                                         }
1718                                         res
1719                                 }
1720                         }
1721                 }
1722                 macro_rules! preimages_to_local_htlcs {
1723                         ($preimages_slice: expr) => {
1724                                 {
1725                                         let mut inp = preimages_slice_to_htlc_outputs!($preimages_slice);
1726                                         let res: Vec<_> = inp.drain(..).map(|e| { (e, dummy_sig.clone(), dummy_sig.clone()) }).collect();
1727                                         res
1728                                 }
1729                         }
1730                 }
1731
1732                 macro_rules! test_preimages_exist {
1733                         ($preimages_slice: expr, $monitor: expr) => {
1734                                 for preimage in $preimages_slice {
1735                                         assert!($monitor.payment_preimages.contains_key(&preimage.1));
1736                                 }
1737                         }
1738                 }
1739
1740                 // Prune with one old state and a local commitment tx holding a few overlaps with the
1741                 // old state.
1742                 let delayed_payment_base_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap());
1743                 let mut monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &delayed_payment_base_key, &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), 0, Script::new());
1744                 monitor.set_their_to_self_delay(10);
1745
1746                 monitor.provide_latest_local_commitment_tx_info(dummy_tx.clone(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..10]));
1747                 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[5..15]), 281474976710655);
1748                 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[15..20]), 281474976710654);
1749                 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[17..20]), 281474976710653);
1750                 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[18..20]), 281474976710652);
1751                 for &(ref preimage, ref hash) in preimages.iter() {
1752                         monitor.provide_payment_preimage(hash, preimage);
1753                 }
1754
1755                 // Now provide a secret, pruning preimages 10-15
1756                 let mut secret = [0; 32];
1757                 secret[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1758                 monitor.provide_secret(281474976710655, secret.clone(), None).unwrap();
1759                 assert_eq!(monitor.payment_preimages.len(), 15);
1760                 test_preimages_exist!(&preimages[0..10], monitor);
1761                 test_preimages_exist!(&preimages[15..20], monitor);
1762
1763                 // Now provide a further secret, pruning preimages 15-17
1764                 secret[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1765                 monitor.provide_secret(281474976710654, secret.clone(), None).unwrap();
1766                 assert_eq!(monitor.payment_preimages.len(), 13);
1767                 test_preimages_exist!(&preimages[0..10], monitor);
1768                 test_preimages_exist!(&preimages[17..20], monitor);
1769
1770                 // Now update local commitment tx info, pruning only element 18 as we still care about the
1771                 // previous commitment tx's preimages too
1772                 monitor.provide_latest_local_commitment_tx_info(dummy_tx.clone(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..5]));
1773                 secret[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1774                 monitor.provide_secret(281474976710653, secret.clone(), None).unwrap();
1775                 assert_eq!(monitor.payment_preimages.len(), 12);
1776                 test_preimages_exist!(&preimages[0..10], monitor);
1777                 test_preimages_exist!(&preimages[18..20], monitor);
1778
1779                 // But if we do it again, we'll prune 5-10
1780                 monitor.provide_latest_local_commitment_tx_info(dummy_tx.clone(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..3]));
1781                 secret[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1782                 monitor.provide_secret(281474976710652, secret.clone(), None).unwrap();
1783                 assert_eq!(monitor.payment_preimages.len(), 5);
1784                 test_preimages_exist!(&preimages[0..5], monitor);
1785         }
1786
1787         // Further testing is done in the ChannelManager integration tests.
1788 }