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