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

   1 use bitcoin::blockdata::block::BlockHeader;
   2 use bitcoin::blockdata::transaction::{TxIn,TxOut,SigHashType,Transaction};
   3 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
   4 use bitcoin::blockdata::script::Script;
   5 use bitcoin::network::serialize;
   6 use bitcoin::util::hash::Sha256dHash;
   7 use bitcoin::util::bip143;
   8
   9 use crypto::digest::Digest;
  10
  11 use secp256k1::{Secp256k1,Message,Signature};
  12 use secp256k1::key::{SecretKey,PublicKey};
  13 use secp256k1;
  14
  15 use ln::msgs::HandleError;
  16 use ln::chan_utils;
  17 use ln::chan_utils::HTLCOutputInCommitment;
  18 use chain::chaininterface::{ChainListener, ChainWatchInterface, BroadcasterInterface};
  19 use chain::transaction::OutPoint;
  20 use util::sha2::Sha256;
  21 use util::byte_utils;
  22
  23 use std::collections::HashMap;
  24 use std::sync::{Arc,Mutex};
  25 use std::{hash,cmp};
  26
  27 pub enum ChannelMonitorUpdateErr {
  28         /// Used to indicate a temporary failure (eg connection to a watchtower failed, but is expected
  29         /// to succeed at some point in the future).
  30         /// Such a failure will "freeze" a channel, preventing us from revoking old states or
  31         /// submitting new commitment transactions to the remote party.
  32         /// ChannelManager::test_restore_channel_monitor can be used to retry the update(s) and restore
  33         /// the channel to an operational state.
  34         TemporaryFailure,
  35         /// Used to indicate no further channel monitor updates will be allowed (eg we've moved on to a
  36         /// different watchtower and cannot update with all watchtowers that were previously informed
  37         /// of this channel). This will force-close the channel in question.
  38         PermanentFailure,
  39 }
  40
  41 /// Simple trait indicating ability to track a set of ChannelMonitors and multiplex events between
  42 /// them. Generally should be implemented by keeping a local SimpleManyChannelMonitor and passing
  43 /// events to it, while also taking any add_update_monitor events and passing them to some remote
  44 /// server(s).
  45 /// Note that any updates to a channel's monitor *must* be applied to each instance of the
  46 /// channel's monitor everywhere (including remote watchtowers) *before* this function returns. If
  47 /// an update occurs and a remote watchtower is left with old state, it may broadcast transactions
  48 /// which we have revoked, allowing our counterparty to claim all funds in the channel!
  49 /// A call to add_update_monitor is needed to register outpoint and its txid with ChainWatchInterface
  50 /// after setting funding_txo in a ChannelMonitor
  51 pub trait ManyChannelMonitor: Send + Sync {
  52         /// Adds or updates a monitor for the given `funding_txo`.
  53         fn add_update_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor) -> Result<(), ChannelMonitorUpdateErr>;
  54 }
  55
  56 /// A simple implementation of a ManyChannelMonitor and ChainListener. Can be used to create a
  57 /// watchtower or watch our own channels.
  58 /// Note that you must provide your own key by which to refer to channels.
  59 /// If you're accepting remote monitors (ie are implementing a watchtower), you must verify that
  60 /// users cannot overwrite a given channel by providing a duplicate key. ie you should probably
  61 /// index by a PublicKey which is required to sign any updates.
  62 /// If you're using this for local monitoring of your own channels, you probably want to use
  63 /// `OutPoint` as the key, which will give you a ManyChannelMonitor implementation.
  64 pub struct SimpleManyChannelMonitor<Key> {
  65         monitors: Mutex<HashMap<Key, ChannelMonitor>>,
  66         chain_monitor: Arc<ChainWatchInterface>,
  67         broadcaster: Arc<BroadcasterInterface>
  68 }
  69
  70 impl<Key : Send + cmp::Eq + hash::Hash> ChainListener for SimpleManyChannelMonitor<Key> {
  71         fn block_connected(&self, _header: &BlockHeader, height: u32, txn_matched: &[&Transaction], _indexes_of_txn_matched: &[u32]) {
  72                 let monitors = self.monitors.lock().unwrap();
  73                 for monitor in monitors.values() {
  74                         let txn_outputs = monitor.block_connected(txn_matched, height, &*self.broadcaster);
  75                         for (ref txid, ref outputs) in txn_outputs {
  76                                 for (idx, output) in outputs.iter().enumerate() {
  77                                         self.chain_monitor.install_watch_outpoint((txid.clone(), idx as u32), &output.script_pubkey);
  78                                 }
  79                         }
  80                 }
  81         }
  82
  83         fn block_disconnected(&self, _: &BlockHeader) { }
  84 }
  85
  86 impl<Key : Send + cmp::Eq + hash::Hash + 'static> SimpleManyChannelMonitor<Key> {
  87         pub fn new(chain_monitor: Arc<ChainWatchInterface>, broadcaster: Arc<BroadcasterInterface>) -> Arc<SimpleManyChannelMonitor<Key>> {
  88                 let res = Arc::new(SimpleManyChannelMonitor {
  89                         monitors: Mutex::new(HashMap::new()),
  90                         chain_monitor,
  91                         broadcaster
  92                 });
  93                 let weak_res = Arc::downgrade(&res);
  94                 res.chain_monitor.register_listener(weak_res);
  95                 res
  96         }
  97
  98         pub fn add_update_monitor_by_key(&self, key: Key, monitor: ChannelMonitor) -> Result<(), HandleError> {
  99                 let mut monitors = self.monitors.lock().unwrap();
 100                 match monitors.get_mut(&key) {
 101                         Some(orig_monitor) => return orig_monitor.insert_combine(monitor),
 102                         None => {}
 103                 };
 104                 match &monitor.funding_txo {
 105                         &None => self.chain_monitor.watch_all_txn(),
 106                         &Some((ref outpoint, ref script)) => {
 107                                 self.chain_monitor.install_watch_tx(&outpoint.txid, script);
 108                                 self.chain_monitor.install_watch_outpoint((outpoint.txid, outpoint.index as u32), script);
 109                         },
 110                 }
 111                 monitors.insert(key, monitor);
 112                 Ok(())
 113         }
 114 }
 115
 116 impl ManyChannelMonitor for SimpleManyChannelMonitor<OutPoint> {
 117         fn add_update_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor) -> Result<(), ChannelMonitorUpdateErr> {
 118                 match self.add_update_monitor_by_key(funding_txo, monitor) {
 119                         Ok(_) => Ok(()),
 120                         Err(_) => Err(ChannelMonitorUpdateErr::PermanentFailure),
 121                 }
 122         }
 123 }
 124
 125 /// If an HTLC expires within this many blocks, don't try to claim it in a shared transaction,
 126 /// instead claiming it in its own individual transaction.
 127 const CLTV_SHARED_CLAIM_BUFFER: u32 = 12;
 128 /// If an HTLC expires within this many blocks, force-close the channel to broadcast the
 129 /// HTLC-Success transaction.
 130 const CLTV_CLAIM_BUFFER: u32 = 6;
 131
 132 #[derive(Clone, PartialEq)]
 133 enum KeyStorage {
 134         PrivMode {
 135                 revocation_base_key: SecretKey,
 136                 htlc_base_key: SecretKey,
 137         },
 138         SigsMode {
 139                 revocation_base_key: PublicKey,
 140                 htlc_base_key: PublicKey,
 141                 sigs: HashMap<Sha256dHash, Signature>,
 142         }
 143 }
 144
 145 #[derive(Clone, PartialEq)]
 146 struct LocalSignedTx {
 147         /// txid of the transaction in tx, just used to make comparison faster
 148         txid: Sha256dHash,
 149         tx: Transaction,
 150         revocation_key: PublicKey,
 151         a_htlc_key: PublicKey,
 152         b_htlc_key: PublicKey,
 153         delayed_payment_key: PublicKey,
 154         feerate_per_kw: u64,
 155         htlc_outputs: Vec<(HTLCOutputInCommitment, Signature, Signature)>,
 156 }
 157
 158 const SERIALIZATION_VERSION: u8 = 1;
 159 const MIN_SERIALIZATION_VERSION: u8 = 1;
 160
 161 pub struct ChannelMonitor {
 162         funding_txo: Option<(OutPoint, Script)>,
 163         commitment_transaction_number_obscure_factor: u64,
 164
 165         key_storage: KeyStorage,
 166         delayed_payment_base_key: PublicKey,
 167         their_htlc_base_key: Option<PublicKey>,
 168         // first is the idx of the first of the two revocation points
 169         their_cur_revocation_points: Option<(u64, PublicKey, Option<PublicKey>)>,
 170
 171         our_to_self_delay: u16,
 172         their_to_self_delay: Option<u16>,
 173
 174         old_secrets: [([u8; 32], u64); 49],
 175         remote_claimable_outpoints: HashMap<Sha256dHash, Vec<HTLCOutputInCommitment>>,
 176         /// We cannot identify HTLC-Success or HTLC-Timeout transactions by themselves on the chain.
 177         /// Nor can we figure out their commitment numbers without the commitment transaction they are
 178         /// spending. Thus, in order to claim them via revocation key, we track all the remote
 179         /// commitment transactions which we find on-chain, mapping them to the commitment number which
 180         /// can be used to derive the revocation key and claim the transactions.
 181         remote_commitment_txn_on_chain: Mutex<HashMap<Sha256dHash, u64>>,
 182         /// Cache used to make pruning of payment_preimages faster.
 183         /// Maps payment_hash values to commitment numbers for remote transactions for non-revoked
 184         /// remote transactions (ie should remain pretty small).
 185         /// Serialized to disk but should generally not be sent to Watchtowers.
 186         remote_hash_commitment_number: HashMap<[u8; 32], u64>,
 187
 188         // We store two local commitment transactions to avoid any race conditions where we may update
 189         // some monitors (potentially on watchtowers) but then fail to update others, resulting in the
 190         // various monitors for one channel being out of sync, and us broadcasting a local
 191         // transaction for which we have deleted claim information on some watchtowers.
 192         prev_local_signed_commitment_tx: Option<LocalSignedTx>,
 193         current_local_signed_commitment_tx: Option<LocalSignedTx>,
 194
 195         payment_preimages: HashMap<[u8; 32], [u8; 32]>,
 196
 197         destination_script: Script,
 198         secp_ctx: Secp256k1<secp256k1::All>, //TODO: dedup this a bit...
 199 }
 200 impl Clone for ChannelMonitor {
 201         fn clone(&self) -> Self {
 202                 ChannelMonitor {
 203                         funding_txo: self.funding_txo.clone(),
 204                         commitment_transaction_number_obscure_factor: self.commitment_transaction_number_obscure_factor.clone(),
 205
 206                         key_storage: self.key_storage.clone(),
 207                         delayed_payment_base_key: self.delayed_payment_base_key.clone(),
 208                         their_htlc_base_key: self.their_htlc_base_key.clone(),
 209                         their_cur_revocation_points: self.their_cur_revocation_points.clone(),
 210
 211                         our_to_self_delay: self.our_to_self_delay,
 212                         their_to_self_delay: self.their_to_self_delay,
 213
 214                         old_secrets: self.old_secrets.clone(),
 215                         remote_claimable_outpoints: self.remote_claimable_outpoints.clone(),
 216                         remote_commitment_txn_on_chain: Mutex::new((*self.remote_commitment_txn_on_chain.lock().unwrap()).clone()),
 217                         remote_hash_commitment_number: self.remote_hash_commitment_number.clone(),
 218
 219                         prev_local_signed_commitment_tx: self.prev_local_signed_commitment_tx.clone(),
 220                         current_local_signed_commitment_tx: self.current_local_signed_commitment_tx.clone(),
 221
 222                         payment_preimages: self.payment_preimages.clone(),
 223
 224                         destination_script: self.destination_script.clone(),
 225                         secp_ctx: self.secp_ctx.clone(),
 226                 }
 227         }
 228 }
 229
 230 #[cfg(any(test, feature = "fuzztarget"))]
 231 /// Used only in testing and fuzztarget to check serialization roundtrips don't change the
 232 /// underlying object
 233 impl PartialEq for ChannelMonitor {
 234         fn eq(&self, other: &Self) -> bool {
 235                 if self.funding_txo != other.funding_txo ||
 236                         self.commitment_transaction_number_obscure_factor != other.commitment_transaction_number_obscure_factor ||
 237                         self.key_storage != other.key_storage ||
 238                         self.delayed_payment_base_key != other.delayed_payment_base_key ||
 239                         self.their_htlc_base_key != other.their_htlc_base_key ||
 240                         self.their_cur_revocation_points != other.their_cur_revocation_points ||
 241                         self.our_to_self_delay != other.our_to_self_delay ||
 242                         self.their_to_self_delay != other.their_to_self_delay ||
 243                         self.remote_claimable_outpoints != other.remote_claimable_outpoints ||
 244                         self.remote_hash_commitment_number != other.remote_hash_commitment_number ||
 245                         self.prev_local_signed_commitment_tx != other.prev_local_signed_commitment_tx ||
 246                         self.current_local_signed_commitment_tx != other.current_local_signed_commitment_tx ||
 247                         self.payment_preimages != other.payment_preimages ||
 248                         self.destination_script != other.destination_script
 249                 {
 250                         false
 251                 } else {
 252                         for (&(ref secret, ref idx), &(ref o_secret, ref o_idx)) in self.old_secrets.iter().zip(other.old_secrets.iter()) {
 253                                 if secret != o_secret || idx != o_idx {
 254                                         return false
 255                                 }
 256                         }
 257                         let us = self.remote_commitment_txn_on_chain.lock().unwrap();
 258                         let them = other.remote_commitment_txn_on_chain.lock().unwrap();
 259                         *us == *them
 260                 }
 261         }
 262 }
 263
 264 impl ChannelMonitor {
 265         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 {
 266                 ChannelMonitor {
 267                         funding_txo: None,
 268                         commitment_transaction_number_obscure_factor: 0,
 269
 270                         key_storage: KeyStorage::PrivMode {
 271                                 revocation_base_key: revocation_base_key.clone(),
 272                                 htlc_base_key: htlc_base_key.clone(),
 273                         },
 274                         delayed_payment_base_key: delayed_payment_base_key.clone(),
 275                         their_htlc_base_key: None,
 276                         their_cur_revocation_points: None,
 277
 278                         our_to_self_delay: our_to_self_delay,
 279                         their_to_self_delay: None,
 280
 281                         old_secrets: [([0; 32], 1 << 48); 49],
 282                         remote_claimable_outpoints: HashMap::new(),
 283                         remote_commitment_txn_on_chain: Mutex::new(HashMap::new()),
 284                         remote_hash_commitment_number: HashMap::new(),
 285
 286                         prev_local_signed_commitment_tx: None,
 287                         current_local_signed_commitment_tx: None,
 288
 289                         payment_preimages: HashMap::new(),
 290
 291                         destination_script: destination_script,
 292                         secp_ctx: Secp256k1::new(),
 293                 }
 294         }
 295
 296         #[inline]
 297         fn place_secret(idx: u64) -> u8 {
 298                 for i in 0..48 {
 299                         if idx & (1 << i) == (1 << i) {
 300                                 return i
 301                         }
 302                 }
 303                 48
 304         }
 305
 306         #[inline]
 307         fn derive_secret(secret: [u8; 32], bits: u8, idx: u64) -> [u8; 32] {
 308                 let mut res: [u8; 32] = secret;
 309                 for i in 0..bits {
 310                         let bitpos = bits - 1 - i;
 311                         if idx & (1 << bitpos) == (1 << bitpos) {
 312                                 res[(bitpos / 8) as usize] ^= 1 << (bitpos & 7);
 313                                 let mut sha = Sha256::new();
 314                                 sha.input(&res);
 315                                 sha.result(&mut res);
 316                         }
 317                 }
 318                 res
 319         }
 320
 321         /// Inserts a revocation secret into this channel monitor. Also optionally tracks the next
 322         /// revocation point which may be required to claim HTLC outputs which we know the preimage of
 323         /// in case the remote end force-closes using their latest state. Prunes old preimages if neither
 324         /// needed by local commitment transactions HTCLs nor by remote ones. Unless we haven't already seen remote
 325         /// commitment transaction's secret, they are de facto pruned (we can use revocation key).
 326         pub(super) fn provide_secret(&mut self, idx: u64, secret: [u8; 32], their_next_revocation_point: Option<(u64, PublicKey)>) -> Result<(), HandleError> {
 327                 let pos = ChannelMonitor::place_secret(idx);
 328                 for i in 0..pos {
 329                         let (old_secret, old_idx) = self.old_secrets[i as usize];
 330                         if ChannelMonitor::derive_secret(secret, pos, old_idx) != old_secret {
 331                                 return Err(HandleError{err: "Previous secret did not match new one", action: None})
 332                         }
 333                 }
 334                 self.old_secrets[pos as usize] = (secret, idx);
 335
 336                 if let Some(new_revocation_point) = their_next_revocation_point {
 337                         match self.their_cur_revocation_points {
 338                                 Some(old_points) => {
 339                                         if old_points.0 == new_revocation_point.0 + 1 {
 340                                                 self.their_cur_revocation_points = Some((old_points.0, old_points.1, Some(new_revocation_point.1)));
 341                                         } else if old_points.0 == new_revocation_point.0 + 2 {
 342                                                 if let Some(old_second_point) = old_points.2 {
 343                                                         self.their_cur_revocation_points = Some((old_points.0 - 1, old_second_point, Some(new_revocation_point.1)));
 344                                                 } else {
 345                                                         self.their_cur_revocation_points = Some((new_revocation_point.0, new_revocation_point.1, None));
 346                                                 }
 347                                         } else {
 348                                                 self.their_cur_revocation_points = Some((new_revocation_point.0, new_revocation_point.1, None));
 349                                         }
 350                                 },
 351                                 None => {
 352                                         self.their_cur_revocation_points = Some((new_revocation_point.0, new_revocation_point.1, None));
 353                                 }
 354                         }
 355                 }
 356
 357                 if !self.payment_preimages.is_empty() {
 358                         let local_signed_commitment_tx = self.current_local_signed_commitment_tx.as_ref().expect("Channel needs at least an initial commitment tx !");
 359                         let prev_local_signed_commitment_tx = self.prev_local_signed_commitment_tx.as_ref();
 360                         let min_idx = self.get_min_seen_secret();
 361                         let remote_hash_commitment_number = &mut self.remote_hash_commitment_number;
 362
 363                         self.payment_preimages.retain(|&k, _| {
 364                                 for &(ref htlc, _, _) in &local_signed_commitment_tx.htlc_outputs {
 365                                         if k == htlc.payment_hash {
 366                                                 return true
 367                                         }
 368                                 }
 369                                 if let Some(prev_local_commitment_tx) = prev_local_signed_commitment_tx {
 370                                         for &(ref htlc, _, _) in prev_local_commitment_tx.htlc_outputs.iter() {
 371                                                 if k == htlc.payment_hash {
 372                                                         return true
 373                                                 }
 374                                         }
 375                                 }
 376                                 let contains = if let Some(cn) = remote_hash_commitment_number.get(&k) {
 377                                         if *cn < min_idx {
 378                                                 return true
 379                                         }
 380                                         true
 381                                 } else { false };
 382                                 if contains {
 383                                         remote_hash_commitment_number.remove(&k);
 384                                 }
 385                                 false
 386                         });
 387                 }
 388
 389                 Ok(())
 390         }
 391
 392         /// Informs this monitor of the latest remote (ie non-broadcastable) commitment transaction.
 393         /// The monitor watches for it to be broadcasted and then uses the HTLC information (and
 394         /// possibly future revocation/preimage information) to claim outputs where possible.
 395         /// We cache also the mapping hash:commitment number to lighten pruning of old preimages by watchtowers.
 396         pub(super) fn provide_latest_remote_commitment_tx_info(&mut self, unsigned_commitment_tx: &Transaction, htlc_outputs: Vec<HTLCOutputInCommitment>, commitment_number: u64) {
 397                 // TODO: Encrypt the htlc_outputs data with the single-hash of the commitment transaction
 398                 // so that a remote monitor doesn't learn anything unless there is a malicious close.
 399                 // (only maybe, sadly we cant do the same for local info, as we need to be aware of
 400                 // timeouts)
 401                 for htlc in &htlc_outputs {
 402                         self.remote_hash_commitment_number.insert(htlc.payment_hash, commitment_number);
 403                 }
 404                 self.remote_claimable_outpoints.insert(unsigned_commitment_tx.txid(), htlc_outputs);
 405         }
 406
 407         /// Informs this monitor of the latest local (ie broadcastable) commitment transaction. The
 408         /// monitor watches for timeouts and may broadcast it if we approach such a timeout. Thus, it
 409         /// is important that any clones of this channel monitor (including remote clones) by kept
 410         /// up-to-date as our local commitment transaction is updated.
 411         /// Panics if set_their_to_self_delay has never been called.
 412         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)>) {
 413                 assert!(self.their_to_self_delay.is_some());
 414                 self.prev_local_signed_commitment_tx = self.current_local_signed_commitment_tx.take();
 415                 self.current_local_signed_commitment_tx = Some(LocalSignedTx {
 416                         txid: signed_commitment_tx.txid(),
 417                         tx: signed_commitment_tx,
 418                         revocation_key: local_keys.revocation_key,
 419                         a_htlc_key: local_keys.a_htlc_key,
 420                         b_htlc_key: local_keys.b_htlc_key,
 421                         delayed_payment_key: local_keys.a_delayed_payment_key,
 422                         feerate_per_kw,
 423                         htlc_outputs,
 424                 });
 425         }
 426
 427         /// Provides a payment_hash->payment_preimage mapping. Will be automatically pruned when all
 428         /// commitment_tx_infos which contain the payment hash have been revoked.
 429         pub(super) fn provide_payment_preimage(&mut self, payment_hash: &[u8; 32], payment_preimage: &[u8; 32]) {
 430                 self.payment_preimages.insert(payment_hash.clone(), payment_preimage.clone());
 431         }
 432
 433         pub fn insert_combine(&mut self, mut other: ChannelMonitor) -> Result<(), HandleError> {
 434                 if self.funding_txo.is_some() {
 435                         // We should be able to compare the entire funding_txo, but in fuzztarget its trivially
 436                         // easy to collide the funding_txo hash and have a different scriptPubKey.
 437                         if other.funding_txo.is_some() && other.funding_txo.as_ref().unwrap().0 != self.funding_txo.as_ref().unwrap().0 {
 438                                 return Err(HandleError{err: "Funding transaction outputs are not identical!", action: None});
 439                         }
 440                 } else {
 441                         self.funding_txo = other.funding_txo.take();
 442                 }
 443                 let other_min_secret = other.get_min_seen_secret();
 444                 let our_min_secret = self.get_min_seen_secret();
 445                 if our_min_secret > other_min_secret {
 446                         self.provide_secret(other_min_secret, other.get_secret(other_min_secret).unwrap(), None)?;
 447                 }
 448                 if our_min_secret >= other_min_secret {
 449                         self.their_cur_revocation_points = other.their_cur_revocation_points;
 450                         for (txid, htlcs) in other.remote_claimable_outpoints.drain() {
 451                                 self.remote_claimable_outpoints.insert(txid, htlcs);
 452                         }
 453                         if let Some(local_tx) = other.prev_local_signed_commitment_tx {
 454                                 self.prev_local_signed_commitment_tx = Some(local_tx);
 455                         }
 456                         if let Some(local_tx) = other.current_local_signed_commitment_tx {
 457                                 self.current_local_signed_commitment_tx = Some(local_tx);
 458                         }
 459                         self.payment_preimages = other.payment_preimages;
 460                 }
 461                 Ok(())
 462         }
 463
 464         /// Panics if commitment_transaction_number_obscure_factor doesn't fit in 48 bits
 465         pub(super) fn set_commitment_obscure_factor(&mut self, commitment_transaction_number_obscure_factor: u64) {
 466                 assert!(commitment_transaction_number_obscure_factor < (1 << 48));
 467                 self.commitment_transaction_number_obscure_factor = commitment_transaction_number_obscure_factor;
 468         }
 469
 470         /// Allows this monitor to scan only for transactions which are applicable. Note that this is
 471         /// optional, without it this monitor cannot be used in an SPV client, but you may wish to
 472         /// avoid this (or call unset_funding_info) on a monitor you wish to send to a watchtower as it
 473         /// provides slightly better privacy.
 474         /// It's the responsability of the caller to register outpoint and script with passing the former
 475         /// value as key to add_update_monitor.
 476         pub(super) fn set_funding_info(&mut self, funding_info: (OutPoint, Script)) {
 477                 self.funding_txo = Some(funding_info);
 478         }
 479
 480         pub(super) fn set_their_htlc_base_key(&mut self, their_htlc_base_key: &PublicKey) {
 481                 self.their_htlc_base_key = Some(their_htlc_base_key.clone());
 482         }
 483
 484         pub(super) fn set_their_to_self_delay(&mut self, their_to_self_delay: u16) {
 485                 self.their_to_self_delay = Some(their_to_self_delay);
 486         }
 487
 488         pub(super) fn unset_funding_info(&mut self) {
 489                 self.funding_txo = None;
 490         }
 491
 492         pub fn get_funding_txo(&self) -> Option<OutPoint> {
 493                 match self.funding_txo {
 494                         Some((outpoint, _)) => Some(outpoint),
 495                         None => None
 496                 }
 497         }
 498
 499         /// Serializes into a vec, with various modes for the exposed pub fns
 500         fn serialize(&self, for_local_storage: bool) -> Vec<u8> {
 501                 let mut res = Vec::new();
 502                 res.push(SERIALIZATION_VERSION);
 503                 res.push(MIN_SERIALIZATION_VERSION);
 504
 505                 match &self.funding_txo {
 506                         &Some((ref outpoint, ref script)) => {
 507                                 res.extend_from_slice(&outpoint.txid[..]);
 508                                 res.extend_from_slice(&byte_utils::be16_to_array(outpoint.index));
 509                                 res.extend_from_slice(&byte_utils::be64_to_array(script.len() as u64));
 510                                 res.extend_from_slice(&script[..]);
 511                         },
 512                         &None => {
 513                                 // We haven't even been initialized...not sure why anyone is serializing us, but
 514                                 // not much to give them.
 515                                 return res;
 516                         },
 517                 }
 518
 519                 // Set in initial Channel-object creation, so should always be set by now:
 520                 res.extend_from_slice(&byte_utils::be48_to_array(self.commitment_transaction_number_obscure_factor));
 521
 522                 match self.key_storage {
 523                         KeyStorage::PrivMode { ref revocation_base_key, ref htlc_base_key } => {
 524                                 res.push(0);
 525                                 res.extend_from_slice(&revocation_base_key[..]);
 526                                 res.extend_from_slice(&htlc_base_key[..]);
 527                         },
 528                         KeyStorage::SigsMode { .. } => unimplemented!(),
 529                 }
 530
 531                 res.extend_from_slice(&self.delayed_payment_base_key.serialize());
 532                 res.extend_from_slice(&self.their_htlc_base_key.as_ref().unwrap().serialize());
 533
 534                 match self.their_cur_revocation_points {
 535                         Some((idx, pubkey, second_option)) => {
 536                                 res.extend_from_slice(&byte_utils::be48_to_array(idx));
 537                                 res.extend_from_slice(&pubkey.serialize());
 538                                 match second_option {
 539                                         Some(second_pubkey) => {
 540                                                 res.extend_from_slice(&second_pubkey.serialize());
 541                                         },
 542                                         None => {
 543                                                 res.extend_from_slice(&[0; 33]);
 544                                         },
 545                                 }
 546                         },
 547                         None => {
 548                                 res.extend_from_slice(&byte_utils::be48_to_array(0));
 549                         },
 550                 }
 551
 552                 res.extend_from_slice(&byte_utils::be16_to_array(self.our_to_self_delay));
 553                 res.extend_from_slice(&byte_utils::be16_to_array(self.their_to_self_delay.unwrap()));
 554
 555                 for &(ref secret, ref idx) in self.old_secrets.iter() {
 556                         res.extend_from_slice(secret);
 557                         res.extend_from_slice(&byte_utils::be64_to_array(*idx));
 558                 }
 559
 560                 macro_rules! serialize_htlc_in_commitment {
 561                         ($htlc_output: expr) => {
 562                                 res.push($htlc_output.offered as u8);
 563                                 res.extend_from_slice(&byte_utils::be64_to_array($htlc_output.amount_msat));
 564                                 res.extend_from_slice(&byte_utils::be32_to_array($htlc_output.cltv_expiry));
 565                                 res.extend_from_slice(&$htlc_output.payment_hash);
 566                                 res.extend_from_slice(&byte_utils::be32_to_array($htlc_output.transaction_output_index));
 567                         }
 568                 }
 569
 570                 res.extend_from_slice(&byte_utils::be64_to_array(self.remote_claimable_outpoints.len() as u64));
 571                 for (txid, htlc_outputs) in self.remote_claimable_outpoints.iter() {
 572                         res.extend_from_slice(&txid[..]);
 573                         res.extend_from_slice(&byte_utils::be64_to_array(htlc_outputs.len() as u64));
 574                         for htlc_output in htlc_outputs.iter() {
 575                                 serialize_htlc_in_commitment!(htlc_output);
 576                         }
 577                 }
 578
 579                 {
 580                         let remote_commitment_txn_on_chain = self.remote_commitment_txn_on_chain.lock().unwrap();
 581                         res.extend_from_slice(&byte_utils::be64_to_array(remote_commitment_txn_on_chain.len() as u64));
 582                         for (txid, commitment_number) in remote_commitment_txn_on_chain.iter() {
 583                                 res.extend_from_slice(&txid[..]);
 584                                 res.extend_from_slice(&byte_utils::be48_to_array(*commitment_number));
 585                         }
 586                 }
 587
 588                 if for_local_storage {
 589                         res.extend_from_slice(&byte_utils::be64_to_array(self.remote_hash_commitment_number.len() as u64));
 590                         for (payment_hash, commitment_number) in self.remote_hash_commitment_number.iter() {
 591                                 res.extend_from_slice(payment_hash);
 592                                 res.extend_from_slice(&byte_utils::be48_to_array(*commitment_number));
 593                         }
 594                 } else {
 595                         res.extend_from_slice(&byte_utils::be64_to_array(0));
 596                 }
 597
 598                 macro_rules! serialize_local_tx {
 599                         ($local_tx: expr) => {
 600                                 let tx_ser = serialize::serialize(&$local_tx.tx).unwrap();
 601                                 res.extend_from_slice(&byte_utils::be64_to_array(tx_ser.len() as u64));
 602                                 res.extend_from_slice(&tx_ser);
 603
 604                                 res.extend_from_slice(&$local_tx.revocation_key.serialize());
 605                                 res.extend_from_slice(&$local_tx.a_htlc_key.serialize());
 606                                 res.extend_from_slice(&$local_tx.b_htlc_key.serialize());
 607                                 res.extend_from_slice(&$local_tx.delayed_payment_key.serialize());
 608
 609                                 res.extend_from_slice(&byte_utils::be64_to_array($local_tx.feerate_per_kw));
 610                                 res.extend_from_slice(&byte_utils::be64_to_array($local_tx.htlc_outputs.len() as u64));
 611                                 for &(ref htlc_output, ref their_sig, ref our_sig) in $local_tx.htlc_outputs.iter() {
 612                                         serialize_htlc_in_commitment!(htlc_output);
 613                                         res.extend_from_slice(&their_sig.serialize_compact(&self.secp_ctx));
 614                                         res.extend_from_slice(&our_sig.serialize_compact(&self.secp_ctx));
 615                                 }
 616                         }
 617                 }
 618
 619                 if let Some(ref prev_local_tx) = self.prev_local_signed_commitment_tx {
 620                         res.push(1);
 621                         serialize_local_tx!(prev_local_tx);
 622                 } else {
 623                         res.push(0);
 624                 }
 625
 626                 if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
 627                         res.push(1);
 628                         serialize_local_tx!(cur_local_tx);
 629                 } else {
 630                         res.push(0);
 631                 }
 632
 633                 res.extend_from_slice(&byte_utils::be64_to_array(self.payment_preimages.len() as u64));
 634                 for payment_preimage in self.payment_preimages.values() {
 635                         res.extend_from_slice(payment_preimage);
 636                 }
 637
 638                 res.extend_from_slice(&byte_utils::be64_to_array(self.destination_script.len() as u64));
 639                 res.extend_from_slice(&self.destination_script[..]);
 640
 641                 res
 642         }
 643
 644         /// Encodes this monitor into a byte array, suitable for writing to disk.
 645         pub fn serialize_for_disk(&self) -> Vec<u8> {
 646                 self.serialize(true)
 647         }
 648
 649         /// Encodes this monitor into a byte array, suitable for sending to a remote watchtower
 650         pub fn serialize_for_watchtower(&self) -> Vec<u8> {
 651                 self.serialize(false)
 652         }
 653
 654         /// Attempts to decode a serialized monitor
 655         pub fn deserialize(data: &[u8]) -> Option<Self> {
 656                 let mut read_pos = 0;
 657                 macro_rules! read_bytes {
 658                         ($byte_count: expr) => {
 659                                 {
 660                                         if ($byte_count as usize) > data.len() - read_pos {
 661                                                 return None;
 662                                         }
 663                                         read_pos += $byte_count as usize;
 664                                         &data[read_pos - $byte_count as usize..read_pos]
 665                                 }
 666                         }
 667                 }
 668
 669                 let secp_ctx = Secp256k1::new();
 670                 macro_rules! unwrap_obj {
 671                         ($key: expr) => {
 672                                 match $key {
 673                                         Ok(res) => res,
 674                                         Err(_) => return None,
 675                                 }
 676                         }
 677                 }
 678
 679                 let _ver = read_bytes!(1)[0];
 680                 let min_ver = read_bytes!(1)[0];
 681                 if min_ver > SERIALIZATION_VERSION {
 682                         return None;
 683                 }
 684
 685                 // Technically this can fail and serialize fail a round-trip, but only for serialization of
 686                 // barely-init'd ChannelMonitors that we can't do anything with.
 687                 let outpoint = OutPoint {
 688                         txid: Sha256dHash::from(read_bytes!(32)),
 689                         index: byte_utils::slice_to_be16(read_bytes!(2)),
 690                 };
 691                 let script_len = byte_utils::slice_to_be64(read_bytes!(8));
 692                 let funding_txo = Some((outpoint, Script::from(read_bytes!(script_len).to_vec())));
 693                 let commitment_transaction_number_obscure_factor = byte_utils::slice_to_be48(read_bytes!(6));
 694
 695                 let key_storage = match read_bytes!(1)[0] {
 696                         0 => {
 697                                 KeyStorage::PrivMode {
 698                                         revocation_base_key: unwrap_obj!(SecretKey::from_slice(&secp_ctx, read_bytes!(32))),
 699                                         htlc_base_key: unwrap_obj!(SecretKey::from_slice(&secp_ctx, read_bytes!(32))),
 700                                 }
 701                         },
 702                         _ => return None,
 703                 };
 704
 705                 let delayed_payment_base_key = unwrap_obj!(PublicKey::from_slice(&secp_ctx, read_bytes!(33)));
 706                 let their_htlc_base_key = Some(unwrap_obj!(PublicKey::from_slice(&secp_ctx, read_bytes!(33))));
 707
 708                 let their_cur_revocation_points = {
 709                         let first_idx = byte_utils::slice_to_be48(read_bytes!(6));
 710                         if first_idx == 0 {
 711                                 None
 712                         } else {
 713                                 let first_point = unwrap_obj!(PublicKey::from_slice(&secp_ctx, read_bytes!(33)));
 714                                 let second_point_slice = read_bytes!(33);
 715                                 if second_point_slice[0..32] == [0; 32] && second_point_slice[32] == 0 {
 716                                         Some((first_idx, first_point, None))
 717                                 } else {
 718                                         Some((first_idx, first_point, Some(unwrap_obj!(PublicKey::from_slice(&secp_ctx, second_point_slice)))))
 719                                 }
 720                         }
 721                 };
 722
 723                 let our_to_self_delay = byte_utils::slice_to_be16(read_bytes!(2));
 724                 let their_to_self_delay = Some(byte_utils::slice_to_be16(read_bytes!(2)));
 725
 726                 let mut old_secrets = [([0; 32], 1 << 48); 49];
 727                 for &mut (ref mut secret, ref mut idx) in old_secrets.iter_mut() {
 728                         secret.copy_from_slice(read_bytes!(32));
 729                         *idx = byte_utils::slice_to_be64(read_bytes!(8));
 730                 }
 731
 732                 macro_rules! read_htlc_in_commitment {
 733                         () => {
 734                                 {
 735                                         let offered = match read_bytes!(1)[0] {
 736                                                 0 => false, 1 => true,
 737                                                 _ => return None,
 738                                         };
 739                                         let amount_msat = byte_utils::slice_to_be64(read_bytes!(8));
 740                                         let cltv_expiry = byte_utils::slice_to_be32(read_bytes!(4));
 741                                         let mut payment_hash = [0; 32];
 742                                         payment_hash[..].copy_from_slice(read_bytes!(32));
 743                                         let transaction_output_index = byte_utils::slice_to_be32(read_bytes!(4));
 744
 745                                         HTLCOutputInCommitment {
 746                                                 offered, amount_msat, cltv_expiry, payment_hash, transaction_output_index
 747                                         }
 748                                 }
 749                         }
 750                 }
 751
 752                 let remote_claimable_outpoints_len = byte_utils::slice_to_be64(read_bytes!(8));
 753                 if remote_claimable_outpoints_len > data.len() as u64 / 64 { return None; }
 754                 let mut remote_claimable_outpoints = HashMap::with_capacity(remote_claimable_outpoints_len as usize);
 755                 for _ in 0..remote_claimable_outpoints_len {
 756                         let txid = Sha256dHash::from(read_bytes!(32));
 757                         let outputs_count = byte_utils::slice_to_be64(read_bytes!(8));
 758                         if outputs_count > data.len() as u64 / 32 { return None; }
 759                         let mut outputs = Vec::with_capacity(outputs_count as usize);
 760                         for _ in 0..outputs_count {
 761                                 outputs.push(read_htlc_in_commitment!());
 762                         }
 763                         if let Some(_) = remote_claimable_outpoints.insert(txid, outputs) {
 764                                 return None;
 765                         }
 766                 }
 767
 768                 let remote_commitment_txn_on_chain_len = byte_utils::slice_to_be64(read_bytes!(8));
 769                 if remote_commitment_txn_on_chain_len > data.len() as u64 / 32 { return None; }
 770                 let mut remote_commitment_txn_on_chain = HashMap::with_capacity(remote_commitment_txn_on_chain_len as usize);
 771                 for _ in 0..remote_commitment_txn_on_chain_len {
 772                         let txid = Sha256dHash::from(read_bytes!(32));
 773                         let commitment_number = byte_utils::slice_to_be48(read_bytes!(6));
 774                         if let Some(_) = remote_commitment_txn_on_chain.insert(txid, commitment_number) {
 775                                 return None;
 776                         }
 777                 }
 778
 779                 let remote_hash_commitment_number_len = byte_utils::slice_to_be64(read_bytes!(8));
 780                 if remote_hash_commitment_number_len > data.len() as u64 / 32 { return None; }
 781                 let mut remote_hash_commitment_number = HashMap::with_capacity(remote_hash_commitment_number_len as usize);
 782                 for _ in 0..remote_hash_commitment_number_len {
 783                         let mut txid = [0; 32];
 784                         txid[..].copy_from_slice(read_bytes!(32));
 785                         let commitment_number = byte_utils::slice_to_be48(read_bytes!(6));
 786                         if let Some(_) = remote_hash_commitment_number.insert(txid, commitment_number) {
 787                                 return None;
 788                         }
 789                 }
 790
 791                 macro_rules! read_local_tx {
 792                         () => {
 793                                 {
 794                                         let tx_len = byte_utils::slice_to_be64(read_bytes!(8));
 795                                         let tx_ser = read_bytes!(tx_len);
 796                                         let tx: Transaction = unwrap_obj!(serialize::deserialize(tx_ser));
 797                                         if serialize::serialize(&tx).unwrap() != tx_ser {
 798                                                 // We check that the tx re-serializes to the same form to ensure there is
 799                                                 // no extra data, and as rust-bitcoin doesn't handle the 0-input ambiguity
 800                                                 // all that well.
 801                                                 return None;
 802                                         }
 803
 804                                         let revocation_key = unwrap_obj!(PublicKey::from_slice(&secp_ctx, read_bytes!(33)));
 805                                         let a_htlc_key = unwrap_obj!(PublicKey::from_slice(&secp_ctx, read_bytes!(33)));
 806                                         let b_htlc_key = unwrap_obj!(PublicKey::from_slice(&secp_ctx, read_bytes!(33)));
 807                                         let delayed_payment_key = unwrap_obj!(PublicKey::from_slice(&secp_ctx, read_bytes!(33)));
 808                                         let feerate_per_kw = byte_utils::slice_to_be64(read_bytes!(8));
 809
 810                                         let htlc_outputs_len = byte_utils::slice_to_be64(read_bytes!(8));
 811                                         if htlc_outputs_len > data.len() as u64 / 128 { return None; }
 812                                         let mut htlc_outputs = Vec::with_capacity(htlc_outputs_len as usize);
 813                                         for _ in 0..htlc_outputs_len {
 814                                                 htlc_outputs.push((read_htlc_in_commitment!(),
 815                                                                 unwrap_obj!(Signature::from_compact(&secp_ctx, read_bytes!(64))),
 816                                                                 unwrap_obj!(Signature::from_compact(&secp_ctx, read_bytes!(64)))));
 817                                         }
 818
 819                                         LocalSignedTx {
 820                                                 txid: tx.txid(),
 821                                                 tx, revocation_key, a_htlc_key, b_htlc_key, delayed_payment_key, feerate_per_kw, htlc_outputs
 822                                         }
 823                                 }
 824                         }
 825                 }
 826
 827                 let prev_local_signed_commitment_tx = match read_bytes!(1)[0] {
 828                         0 => None,
 829                         1 => {
 830                                 Some(read_local_tx!())
 831                         },
 832                         _ => return None,
 833                 };
 834
 835                 let current_local_signed_commitment_tx = match read_bytes!(1)[0] {
 836                         0 => None,
 837                         1 => {
 838                                 Some(read_local_tx!())
 839                         },
 840                         _ => return None,
 841                 };
 842
 843                 let payment_preimages_len = byte_utils::slice_to_be64(read_bytes!(8));
 844                 if payment_preimages_len > data.len() as u64 / 32 { return None; }
 845                 let mut payment_preimages = HashMap::with_capacity(payment_preimages_len as usize);
 846                 let mut sha = Sha256::new();
 847                 for _ in 0..payment_preimages_len {
 848                         let mut preimage = [0; 32];
 849                         preimage[..].copy_from_slice(read_bytes!(32));
 850                         sha.reset();
 851                         sha.input(&preimage);
 852                         let mut hash = [0; 32];
 853                         sha.result(&mut hash);
 854                         if let Some(_) = payment_preimages.insert(hash, preimage) {
 855                                 return None;
 856                         }
 857                 }
 858
 859                 let destination_script_len = byte_utils::slice_to_be64(read_bytes!(8));
 860                 let destination_script = Script::from(read_bytes!(destination_script_len).to_vec());
 861
 862                 Some(ChannelMonitor {
 863                         funding_txo,
 864                         commitment_transaction_number_obscure_factor,
 865
 866                         key_storage,
 867                         delayed_payment_base_key,
 868                         their_htlc_base_key,
 869                         their_cur_revocation_points,
 870
 871                         our_to_self_delay,
 872                         their_to_self_delay,
 873
 874                         old_secrets,
 875                         remote_claimable_outpoints,
 876                         remote_commitment_txn_on_chain: Mutex::new(remote_commitment_txn_on_chain),
 877                         remote_hash_commitment_number,
 878
 879                         prev_local_signed_commitment_tx,
 880                         current_local_signed_commitment_tx,
 881
 882                         payment_preimages,
 883
 884                         destination_script,
 885                         secp_ctx,
 886                 })
 887         }
 888
 889         //TODO: Functions to serialize/deserialize (with different forms depending on which information
 890         //we want to leave out (eg funding_txo, etc).
 891
 892         /// Can only fail if idx is < get_min_seen_secret
 893         pub fn get_secret(&self, idx: u64) -> Result<[u8; 32], HandleError> {
 894                 for i in 0..self.old_secrets.len() {
 895                         if (idx & (!((1 << i) - 1))) == self.old_secrets[i].1 {
 896                                 return Ok(ChannelMonitor::derive_secret(self.old_secrets[i].0, i as u8, idx))
 897                         }
 898                 }
 899                 assert!(idx < self.get_min_seen_secret());
 900                 Err(HandleError{err: "idx too low", action: None})
 901         }
 902
 903         pub fn get_min_seen_secret(&self) -> u64 {
 904                 //TODO This can be optimized?
 905                 let mut min = 1 << 48;
 906                 for &(_, idx) in self.old_secrets.iter() {
 907                         if idx < min {
 908                                 min = idx;
 909                         }
 910                 }
 911                 min
 912         }
 913
 914         /// Attempts to claim a remote commitment transaction's outputs using the revocation key and
 915         /// data in remote_claimable_outpoints. Will directly claim any HTLC outputs which expire at a
 916         /// height > height + CLTV_SHARED_CLAIM_BUFFER. In any case, will install monitoring for
 917         /// HTLC-Success/HTLC-Timeout transactions, and claim them using the revocation key (if
 918         /// applicable) as well.
 919         fn check_spend_remote_transaction(&self, tx: &Transaction, height: u32) -> (Vec<Transaction>, (Sha256dHash, Vec<TxOut>)) {
 920                 // Most secp and related errors trying to create keys means we have no hope of constructing
 921                 // a spend transaction...so we return no transactions to broadcast
 922                 let mut txn_to_broadcast = Vec::new();
 923                 let mut watch_outputs = Vec::new();
 924
 925                 let commitment_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
 926                 let per_commitment_option = self.remote_claimable_outpoints.get(&commitment_txid);
 927
 928                 macro_rules! ignore_error {
 929                         ( $thing : expr ) => {
 930                                 match $thing {
 931                                         Ok(a) => a,
 932                                         Err(_) => return (txn_to_broadcast, (commitment_txid, watch_outputs))
 933                                 }
 934                         };
 935                 }
 936
 937                 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);
 938                 if commitment_number >= self.get_min_seen_secret() {
 939                         let secret = self.get_secret(commitment_number).unwrap();
 940                         let per_commitment_key = ignore_error!(SecretKey::from_slice(&self.secp_ctx, &secret));
 941                         let (revocation_pubkey, b_htlc_key) = match self.key_storage {
 942                                 KeyStorage::PrivMode { ref revocation_base_key, ref htlc_base_key } => {
 943                                         let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
 944                                         (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &PublicKey::from_secret_key(&self.secp_ctx, &revocation_base_key))),
 945                                         ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &PublicKey::from_secret_key(&self.secp_ctx, &htlc_base_key))))
 946                                 },
 947                                 KeyStorage::SigsMode { ref revocation_base_key, ref htlc_base_key, .. } => {
 948                                         let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
 949                                         (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &revocation_base_key)),
 950                                         ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &htlc_base_key)))
 951                                 },
 952                         };
 953                         let delayed_key = ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key), &self.delayed_payment_base_key));
 954                         let a_htlc_key = match self.their_htlc_base_key {
 955                                 None => return (txn_to_broadcast, (commitment_txid, watch_outputs)),
 956                                 Some(their_htlc_base_key) => ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key), &their_htlc_base_key)),
 957                         };
 958
 959                         let revokeable_redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.our_to_self_delay, &delayed_key);
 960                         let revokeable_p2wsh = revokeable_redeemscript.to_v0_p2wsh();
 961
 962                         let mut total_value = 0;
 963                         let mut values = Vec::new();
 964                         let mut inputs = Vec::new();
 965                         let mut htlc_idxs = Vec::new();
 966
 967                         for (idx, outp) in tx.output.iter().enumerate() {
 968                                 if outp.script_pubkey == revokeable_p2wsh {
 969                                         inputs.push(TxIn {
 970                                                 previous_output: BitcoinOutPoint {
 971                                                         txid: commitment_txid,
 972                                                         vout: idx as u32,
 973                                                 },
 974                                                 script_sig: Script::new(),
 975                                                 sequence: 0xfffffffd,
 976                                                 witness: Vec::new(),
 977                                         });
 978                                         htlc_idxs.push(None);
 979                                         values.push(outp.value);
 980                                         total_value += outp.value;
 981                                         break; // There can only be one of these
 982                                 }
 983                         }
 984
 985                         macro_rules! sign_input {
 986                                 ($sighash_parts: expr, $input: expr, $htlc_idx: expr, $amount: expr) => {
 987                                         {
 988                                                 let (sig, redeemscript) = match self.key_storage {
 989                                                         KeyStorage::PrivMode { ref revocation_base_key, .. } => {
 990                                                                 let redeemscript = if $htlc_idx.is_none() { revokeable_redeemscript.clone() } else {
 991                                                                         let htlc = &per_commitment_option.unwrap()[$htlc_idx.unwrap()];
 992                                                                         chan_utils::get_htlc_redeemscript_with_explicit_keys(htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey)
 993                                                                 };
 994                                                                 let sighash = ignore_error!(Message::from_slice(&$sighash_parts.sighash_all(&$input, &redeemscript, $amount)[..]));
 995                                                                 let revocation_key = ignore_error!(chan_utils::derive_private_revocation_key(&self.secp_ctx, &per_commitment_key, &revocation_base_key));
 996                                                                 (self.secp_ctx.sign(&sighash, &revocation_key), redeemscript)
 997                                                         },
 998                                                         KeyStorage::SigsMode { .. } => {
 999                                                                 unimplemented!();
1000                                                         }
1001                                                 };
1002                                                 $input.witness.push(sig.serialize_der(&self.secp_ctx).to_vec());
1003                                                 $input.witness[0].push(SigHashType::All as u8);
1004                                                 if $htlc_idx.is_none() {
1005                                                         $input.witness.push(vec!(1));
1006                                                 } else {
1007                                                         $input.witness.push(revocation_pubkey.serialize().to_vec());
1008                                                 }
1009                                                 $input.witness.push(redeemscript.into_bytes());
1010                                         }
1011                                 }
1012                         }
1013
1014                         if let Some(per_commitment_data) = per_commitment_option {
1015                                 inputs.reserve_exact(per_commitment_data.len());
1016
1017                                 for (idx, htlc) in per_commitment_data.iter().enumerate() {
1018                                         let expected_script = chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey);
1019                                         if htlc.transaction_output_index as usize >= tx.output.len() ||
1020                                                         tx.output[htlc.transaction_output_index as usize].value != htlc.amount_msat / 1000 ||
1021                                                         tx.output[htlc.transaction_output_index as usize].script_pubkey != expected_script.to_v0_p2wsh() {
1022                                                 return (txn_to_broadcast, (commitment_txid, watch_outputs)); // Corrupted per_commitment_data, fuck this user
1023                                         }
1024                                         let input = TxIn {
1025                                                 previous_output: BitcoinOutPoint {
1026                                                         txid: commitment_txid,
1027                                                         vout: htlc.transaction_output_index,
1028                                                 },
1029                                                 script_sig: Script::new(),
1030                                                 sequence: 0xfffffffd,
1031                                                 witness: Vec::new(),
1032                                         };
1033                                         if htlc.cltv_expiry > height + CLTV_SHARED_CLAIM_BUFFER {
1034                                                 inputs.push(input);
1035                                                 htlc_idxs.push(Some(idx));
1036                                                 values.push(tx.output[htlc.transaction_output_index as usize].value);
1037                                                 total_value += htlc.amount_msat / 1000;
1038                                         } else {
1039                                                 let mut single_htlc_tx = Transaction {
1040                                                         version: 2,
1041                                                         lock_time: 0,
1042                                                         input: vec![input],
1043                                                         output: vec!(TxOut {
1044                                                                 script_pubkey: self.destination_script.clone(),
1045                                                                 value: htlc.amount_msat / 1000, //TODO: - fee
1046                                                         }),
1047                                                 };
1048                                                 let sighash_parts = bip143::SighashComponents::new(&single_htlc_tx);
1049                                                 sign_input!(sighash_parts, single_htlc_tx.input[0], Some(idx), htlc.amount_msat / 1000);
1050                                                 txn_to_broadcast.push(single_htlc_tx); // TODO: This is not yet tested in ChannelManager!
1051                                         }
1052                                 }
1053                         }
1054
1055                         if !inputs.is_empty() || !txn_to_broadcast.is_empty() { // ie we're confident this is actually ours
1056                                 // We're definitely a remote commitment transaction!
1057                                 watch_outputs.append(&mut tx.output.clone());
1058                                 self.remote_commitment_txn_on_chain.lock().unwrap().insert(commitment_txid, commitment_number);
1059                         }
1060                         if inputs.is_empty() { return (txn_to_broadcast, (commitment_txid, watch_outputs)); } // Nothing to be done...probably a false positive/local tx
1061
1062                         let outputs = vec!(TxOut {
1063                                 script_pubkey: self.destination_script.clone(),
1064                                 value: total_value, //TODO: - fee
1065                         });
1066                         let mut spend_tx = Transaction {
1067                                 version: 2,
1068                                 lock_time: 0,
1069                                 input: inputs,
1070                                 output: outputs,
1071                         };
1072
1073                         let mut values_drain = values.drain(..);
1074                         let sighash_parts = bip143::SighashComponents::new(&spend_tx);
1075
1076                         for (input, htlc_idx) in spend_tx.input.iter_mut().zip(htlc_idxs.iter()) {
1077                                 let value = values_drain.next().unwrap();
1078                                 sign_input!(sighash_parts, input, htlc_idx, value);
1079                         }
1080
1081                         txn_to_broadcast.push(spend_tx);
1082                 } else if let Some(per_commitment_data) = per_commitment_option {
1083                         // While this isn't useful yet, there is a potential race where if a counterparty
1084                         // revokes a state at the same time as the commitment transaction for that state is
1085                         // confirmed, and the watchtower receives the block before the user, the user could
1086                         // upload a new ChannelMonitor with the revocation secret but the watchtower has
1087                         // already processed the block, resulting in the remote_commitment_txn_on_chain entry
1088                         // not being generated by the above conditional. Thus, to be safe, we go ahead and
1089                         // insert it here.
1090                         watch_outputs.append(&mut tx.output.clone());
1091                         self.remote_commitment_txn_on_chain.lock().unwrap().insert(commitment_txid, commitment_number);
1092
1093                         if let Some(revocation_points) = self.their_cur_revocation_points {
1094                                 let revocation_point_option =
1095                                         if revocation_points.0 == commitment_number { Some(&revocation_points.1) }
1096                                         else if let Some(point) = revocation_points.2.as_ref() {
1097                                                 if revocation_points.0 == commitment_number + 1 { Some(point) } else { None }
1098                                         } else { None };
1099                                 if let Some(revocation_point) = revocation_point_option {
1100                                         let (revocation_pubkey, b_htlc_key) = match self.key_storage {
1101                                                 KeyStorage::PrivMode { ref revocation_base_key, ref htlc_base_key } => {
1102                                                         (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, revocation_point, &PublicKey::from_secret_key(&self.secp_ctx, &revocation_base_key))),
1103                                                         ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &PublicKey::from_secret_key(&self.secp_ctx, &htlc_base_key))))
1104                                                 },
1105                                                 KeyStorage::SigsMode { ref revocation_base_key, ref htlc_base_key, .. } => {
1106                                                         (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, revocation_point, &revocation_base_key)),
1107                                                         ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &htlc_base_key)))
1108                                                 },
1109                                         };
1110                                         let a_htlc_key = match self.their_htlc_base_key {
1111                                                 None => return (txn_to_broadcast, (commitment_txid, watch_outputs)),
1112                                                 Some(their_htlc_base_key) => ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &their_htlc_base_key)),
1113                                         };
1114
1115                                         let mut total_value = 0;
1116                                         let mut values = Vec::new();
1117                                         let mut inputs = Vec::new();
1118
1119                                         macro_rules! sign_input {
1120                                                 ($sighash_parts: expr, $input: expr, $amount: expr, $preimage: expr) => {
1121                                                         {
1122                                                                 let (sig, redeemscript) = match self.key_storage {
1123                                                                         KeyStorage::PrivMode { ref htlc_base_key, .. } => {
1124                                                                                 let htlc = &per_commitment_option.unwrap()[$input.sequence as usize];
1125                                                                                 let redeemscript = chan_utils::get_htlc_redeemscript_with_explicit_keys(htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey);
1126                                                                                 let sighash = ignore_error!(Message::from_slice(&$sighash_parts.sighash_all(&$input, &redeemscript, $amount)[..]));
1127                                                                                 let htlc_key = ignore_error!(chan_utils::derive_private_key(&self.secp_ctx, revocation_point, &htlc_base_key));
1128                                                                                 (self.secp_ctx.sign(&sighash, &htlc_key), redeemscript)
1129                                                                         },
1130                                                                         KeyStorage::SigsMode { .. } => {
1131                                                                                 unimplemented!();
1132                                                                         }
1133                                                                 };
1134                                                                 $input.witness.push(sig.serialize_der(&self.secp_ctx).to_vec());
1135                                                                 $input.witness[0].push(SigHashType::All as u8);
1136                                                                 $input.witness.push($preimage);
1137                                                                 $input.witness.push(redeemscript.into_bytes());
1138                                                         }
1139                                                 }
1140                                         }
1141
1142                                         for (idx, htlc) in per_commitment_data.iter().enumerate() {
1143                                                 if let Some(payment_preimage) = self.payment_preimages.get(&htlc.payment_hash) {
1144                                                         let input = TxIn {
1145                                                                 previous_output: BitcoinOutPoint {
1146                                                                         txid: commitment_txid,
1147                                                                         vout: htlc.transaction_output_index,
1148                                                                 },
1149                                                                 script_sig: Script::new(),
1150                                                                 sequence: idx as u32, // reset to 0xfffffffd in sign_input
1151                                                                 witness: Vec::new(),
1152                                                         };
1153                                                         if htlc.cltv_expiry > height + CLTV_SHARED_CLAIM_BUFFER {
1154                                                                 inputs.push(input);
1155                                                                 values.push((tx.output[htlc.transaction_output_index as usize].value, payment_preimage));
1156                                                                 total_value += htlc.amount_msat / 1000;
1157                                                         } else {
1158                                                                 let mut single_htlc_tx = Transaction {
1159                                                                         version: 2,
1160                                                                         lock_time: 0,
1161                                                                         input: vec![input],
1162                                                                         output: vec!(TxOut {
1163                                                                                 script_pubkey: self.destination_script.clone(),
1164                                                                                 value: htlc.amount_msat / 1000, //TODO: - fee
1165                                                                         }),
1166                                                                 };
1167                                                                 let sighash_parts = bip143::SighashComponents::new(&single_htlc_tx);
1168                                                                 sign_input!(sighash_parts, single_htlc_tx.input[0], htlc.amount_msat / 1000, payment_preimage.to_vec());
1169                                                                 txn_to_broadcast.push(single_htlc_tx);
1170                                                         }
1171                                                 }
1172                                         }
1173
1174                                         if inputs.is_empty() { return (txn_to_broadcast, (commitment_txid, watch_outputs)); } // Nothing to be done...probably a false positive/local tx
1175
1176                                         let outputs = vec!(TxOut {
1177                                                 script_pubkey: self.destination_script.clone(),
1178                                                 value: total_value, //TODO: - fee
1179                                         });
1180                                         let mut spend_tx = Transaction {
1181                                                 version: 2,
1182                                                 lock_time: 0,
1183                                                 input: inputs,
1184                                                 output: outputs,
1185                                         };
1186
1187                                         let mut values_drain = values.drain(..);
1188                                         let sighash_parts = bip143::SighashComponents::new(&spend_tx);
1189
1190                                         for input in spend_tx.input.iter_mut() {
1191                                                 let value = values_drain.next().unwrap();
1192                                                 sign_input!(sighash_parts, input, value.0, value.1.to_vec());
1193                                         }
1194
1195                                         txn_to_broadcast.push(spend_tx);
1196                                 }
1197                         }
1198                 } else {
1199                         //TODO: For each input check if its in our remote_commitment_txn_on_chain map!
1200                 }
1201
1202                 (txn_to_broadcast, (commitment_txid, watch_outputs))
1203         }
1204
1205         fn broadcast_by_local_state(&self, local_tx: &LocalSignedTx) -> Vec<Transaction> {
1206                 let mut res = Vec::with_capacity(local_tx.htlc_outputs.len());
1207
1208                 for &(ref htlc, ref their_sig, ref our_sig) in local_tx.htlc_outputs.iter() {
1209                         if htlc.offered {
1210                                 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);
1211
1212                                 htlc_timeout_tx.input[0].witness.push(Vec::new()); // First is the multisig dummy
1213
1214                                 htlc_timeout_tx.input[0].witness.push(their_sig.serialize_der(&self.secp_ctx).to_vec());
1215                                 htlc_timeout_tx.input[0].witness[1].push(SigHashType::All as u8);
1216                                 htlc_timeout_tx.input[0].witness.push(our_sig.serialize_der(&self.secp_ctx).to_vec());
1217                                 htlc_timeout_tx.input[0].witness[2].push(SigHashType::All as u8);
1218
1219                                 htlc_timeout_tx.input[0].witness.push(Vec::new());
1220                                 htlc_timeout_tx.input[0].witness.push(chan_utils::get_htlc_redeemscript_with_explicit_keys(htlc, &local_tx.a_htlc_key, &local_tx.b_htlc_key, &local_tx.revocation_key).into_bytes());
1221
1222                                 res.push(htlc_timeout_tx);
1223                         } else {
1224                                 if let Some(payment_preimage) = self.payment_preimages.get(&htlc.payment_hash) {
1225                                         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);
1226
1227                                         htlc_success_tx.input[0].witness.push(Vec::new()); // First is the multisig dummy
1228
1229                                         htlc_success_tx.input[0].witness.push(their_sig.serialize_der(&self.secp_ctx).to_vec());
1230                                         htlc_success_tx.input[0].witness[1].push(SigHashType::All as u8);
1231                                         htlc_success_tx.input[0].witness.push(our_sig.serialize_der(&self.secp_ctx).to_vec());
1232                                         htlc_success_tx.input[0].witness[2].push(SigHashType::All as u8);
1233
1234                                         htlc_success_tx.input[0].witness.push(payment_preimage.to_vec());
1235                                         htlc_success_tx.input[0].witness.push(chan_utils::get_htlc_redeemscript_with_explicit_keys(htlc, &local_tx.a_htlc_key, &local_tx.b_htlc_key, &local_tx.revocation_key).into_bytes());
1236
1237                                         res.push(htlc_success_tx);
1238                                 }
1239                         }
1240                 }
1241
1242                 res
1243         }
1244
1245         /// Attempts to claim any claimable HTLCs in a commitment transaction which was not (yet)
1246         /// revoked using data in local_claimable_outpoints.
1247         /// Should not be used if check_spend_revoked_transaction succeeds.
1248         fn check_spend_local_transaction(&self, tx: &Transaction, _height: u32) -> Vec<Transaction> {
1249                 let commitment_txid = tx.txid();
1250                 if let &Some(ref local_tx) = &self.current_local_signed_commitment_tx {
1251                         if local_tx.txid == commitment_txid {
1252                                 return self.broadcast_by_local_state(local_tx);
1253                         }
1254                 }
1255                 if let &Some(ref local_tx) = &self.prev_local_signed_commitment_tx {
1256                         if local_tx.txid == commitment_txid {
1257                                 return self.broadcast_by_local_state(local_tx);
1258                         }
1259                 }
1260                 Vec::new()
1261         }
1262
1263         fn block_connected(&self, txn_matched: &[&Transaction], height: u32, broadcaster: &BroadcasterInterface)-> Vec<(Sha256dHash, Vec<TxOut>)> {
1264                 let mut watch_outputs = Vec::new();
1265                 for tx in txn_matched {
1266                         for txin in tx.input.iter() {
1267                                 if self.funding_txo.is_none() || (txin.previous_output.txid == self.funding_txo.as_ref().unwrap().0.txid && txin.previous_output.vout == self.funding_txo.as_ref().unwrap().0.index as u32) {
1268                                         let (mut txn, new_outputs) = self.check_spend_remote_transaction(tx, height);
1269                                         if !new_outputs.1.is_empty() {
1270                                                 watch_outputs.push(new_outputs);
1271                                         }
1272                                         if txn.is_empty() {
1273                                                 txn = self.check_spend_local_transaction(tx, height);
1274                                         }
1275                                         for tx in txn.iter() {
1276                                                 broadcaster.broadcast_transaction(tx);
1277                                         }
1278                                 }
1279                         }
1280                 }
1281                 if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
1282                         let mut needs_broadcast = false;
1283                         for &(ref htlc, _, _) in cur_local_tx.htlc_outputs.iter() {
1284                                 if htlc.cltv_expiry <= height + CLTV_CLAIM_BUFFER {
1285                                         if htlc.offered || self.payment_preimages.contains_key(&htlc.payment_hash) {
1286                                                 needs_broadcast = true;
1287                                         }
1288                                 }
1289                         }
1290
1291                         if needs_broadcast {
1292                                 broadcaster.broadcast_transaction(&cur_local_tx.tx);
1293                                 for tx in self.broadcast_by_local_state(&cur_local_tx) {
1294                                         broadcaster.broadcast_transaction(&tx);
1295                                 }
1296                         }
1297                 }
1298                 watch_outputs
1299         }
1300
1301         pub fn would_broadcast_at_height(&self, height: u32) -> bool {
1302                 if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
1303                         for &(ref htlc, _, _) in cur_local_tx.htlc_outputs.iter() {
1304                                 if htlc.cltv_expiry <= height + CLTV_CLAIM_BUFFER {
1305                                         if htlc.offered || self.payment_preimages.contains_key(&htlc.payment_hash) {
1306                                                 return true;
1307                                         }
1308                                 }
1309                         }
1310                 }
1311                 false
1312         }
1313 }
1314
1315 #[cfg(test)]
1316 mod tests {
1317         use bitcoin::blockdata::script::Script;
1318         use bitcoin::blockdata::transaction::Transaction;
1319         use crypto::digest::Digest;
1320         use hex;
1321         use ln::channelmonitor::ChannelMonitor;
1322         use ln::chan_utils::{HTLCOutputInCommitment, TxCreationKeys};
1323         use util::sha2::Sha256;
1324         use secp256k1::key::{SecretKey,PublicKey};
1325         use secp256k1::{Secp256k1, Signature};
1326         use rand::{thread_rng,Rng};
1327
1328         #[test]
1329         fn test_per_commitment_storage() {
1330                 // Test vectors from BOLT 3:
1331                 let mut secrets: Vec<[u8; 32]> = Vec::new();
1332                 let mut monitor: ChannelMonitor;
1333                 let secp_ctx = Secp256k1::new();
1334
1335                 macro_rules! test_secrets {
1336                         () => {
1337                                 let mut idx = 281474976710655;
1338                                 for secret in secrets.iter() {
1339                                         assert_eq!(monitor.get_secret(idx).unwrap(), *secret);
1340                                         idx -= 1;
1341                                 }
1342                                 assert_eq!(monitor.get_min_seen_secret(), idx + 1);
1343                                 assert!(monitor.get_secret(idx).is_err());
1344                         };
1345                 }
1346
1347                 let delayed_payment_base_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap());
1348
1349                 {
1350                         // insert_secret correct sequence
1351                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &delayed_payment_base_key, &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), 0, Script::new());
1352                         secrets.clear();
1353
1354                         secrets.push([0; 32]);
1355                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1356                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone(), None).unwrap();
1357                         test_secrets!();
1358
1359                         secrets.push([0; 32]);
1360                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1361                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone(), None).unwrap();
1362                         test_secrets!();
1363
1364                         secrets.push([0; 32]);
1365                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1366                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone(), None).unwrap();
1367                         test_secrets!();
1368
1369                         secrets.push([0; 32]);
1370                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1371                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone(), None).unwrap();
1372                         test_secrets!();
1373
1374                         secrets.push([0; 32]);
1375                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
1376                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone(), None).unwrap();
1377                         test_secrets!();
1378
1379                         secrets.push([0; 32]);
1380                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
1381                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone(), None).unwrap();
1382                         test_secrets!();
1383
1384                         secrets.push([0; 32]);
1385                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
1386                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone(), None).unwrap();
1387                         test_secrets!();
1388
1389                         secrets.push([0; 32]);
1390                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
1391                         monitor.provide_secret(281474976710648, secrets.last().unwrap().clone(), None).unwrap();
1392                         test_secrets!();
1393                 }
1394
1395                 {
1396                         // insert_secret #1 incorrect
1397                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &delayed_payment_base_key, &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), 0, Script::new());
1398                         secrets.clear();
1399
1400                         secrets.push([0; 32]);
1401                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
1402                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone(), None).unwrap();
1403                         test_secrets!();
1404
1405                         secrets.push([0; 32]);
1406                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1407                         assert_eq!(monitor.provide_secret(281474976710654, secrets.last().unwrap().clone(), None).unwrap_err().err,
1408                                         "Previous secret did not match new one");
1409                 }
1410
1411                 {
1412                         // insert_secret #2 incorrect (#1 derived from incorrect)
1413                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &delayed_payment_base_key, &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), 0, Script::new());
1414                         secrets.clear();
1415
1416                         secrets.push([0; 32]);
1417                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
1418                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone(), None).unwrap();
1419                         test_secrets!();
1420
1421                         secrets.push([0; 32]);
1422                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("dddc3a8d14fddf2b68fa8c7fbad2748274937479dd0f8930d5ebb4ab6bd866a3").unwrap());
1423                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone(), None).unwrap();
1424                         test_secrets!();
1425
1426                         secrets.push([0; 32]);
1427                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1428                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone(), None).unwrap();
1429                         test_secrets!();
1430
1431                         secrets.push([0; 32]);
1432                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1433                         assert_eq!(monitor.provide_secret(281474976710652, secrets.last().unwrap().clone(), None).unwrap_err().err,
1434                                         "Previous secret did not match new one");
1435                 }
1436
1437                 {
1438                         // insert_secret #3 incorrect
1439                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &delayed_payment_base_key, &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), 0, Script::new());
1440                         secrets.clear();
1441
1442                         secrets.push([0; 32]);
1443                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1444                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone(), None).unwrap();
1445                         test_secrets!();
1446
1447                         secrets.push([0; 32]);
1448                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1449                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone(), None).unwrap();
1450                         test_secrets!();
1451
1452                         secrets.push([0; 32]);
1453                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c51a18b13e8527e579ec56365482c62f180b7d5760b46e9477dae59e87ed423a").unwrap());
1454                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone(), None).unwrap();
1455                         test_secrets!();
1456
1457                         secrets.push([0; 32]);
1458                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1459                         assert_eq!(monitor.provide_secret(281474976710652, secrets.last().unwrap().clone(), None).unwrap_err().err,
1460                                         "Previous secret did not match new one");
1461                 }
1462
1463                 {
1464                         // insert_secret #4 incorrect (1,2,3 derived from incorrect)
1465                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &delayed_payment_base_key, &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), 0, Script::new());
1466                         secrets.clear();
1467
1468                         secrets.push([0; 32]);
1469                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
1470                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone(), None).unwrap();
1471                         test_secrets!();
1472
1473                         secrets.push([0; 32]);
1474                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("dddc3a8d14fddf2b68fa8c7fbad2748274937479dd0f8930d5ebb4ab6bd866a3").unwrap());
1475                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone(), None).unwrap();
1476                         test_secrets!();
1477
1478                         secrets.push([0; 32]);
1479                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c51a18b13e8527e579ec56365482c62f180b7d5760b46e9477dae59e87ed423a").unwrap());
1480                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone(), None).unwrap();
1481                         test_secrets!();
1482
1483                         secrets.push([0; 32]);
1484                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("ba65d7b0ef55a3ba300d4e87af29868f394f8f138d78a7011669c79b37b936f4").unwrap());
1485                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone(), None).unwrap();
1486                         test_secrets!();
1487
1488                         secrets.push([0; 32]);
1489                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
1490                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone(), None).unwrap();
1491                         test_secrets!();
1492
1493                         secrets.push([0; 32]);
1494                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
1495                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone(), None).unwrap();
1496                         test_secrets!();
1497
1498                         secrets.push([0; 32]);
1499                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
1500                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone(), None).unwrap();
1501                         test_secrets!();
1502
1503                         secrets.push([0; 32]);
1504                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
1505                         assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone(), None).unwrap_err().err,
1506                                         "Previous secret did not match new one");
1507                 }
1508
1509                 {
1510                         // insert_secret #5 incorrect
1511                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &delayed_payment_base_key, &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), 0, Script::new());
1512                         secrets.clear();
1513
1514                         secrets.push([0; 32]);
1515                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1516                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone(), None).unwrap();
1517                         test_secrets!();
1518
1519                         secrets.push([0; 32]);
1520                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1521                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone(), None).unwrap();
1522                         test_secrets!();
1523
1524                         secrets.push([0; 32]);
1525                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1526                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone(), None).unwrap();
1527                         test_secrets!();
1528
1529                         secrets.push([0; 32]);
1530                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1531                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone(), None).unwrap();
1532                         test_secrets!();
1533
1534                         secrets.push([0; 32]);
1535                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("631373ad5f9ef654bb3dade742d09504c567edd24320d2fcd68e3cc47e2ff6a6").unwrap());
1536                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone(), None).unwrap();
1537                         test_secrets!();
1538
1539                         secrets.push([0; 32]);
1540                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
1541                         assert_eq!(monitor.provide_secret(281474976710650, secrets.last().unwrap().clone(), None).unwrap_err().err,
1542                                         "Previous secret did not match new one");
1543                 }
1544
1545                 {
1546                         // insert_secret #6 incorrect (5 derived from incorrect)
1547                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &delayed_payment_base_key, &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), 0, Script::new());
1548                         secrets.clear();
1549
1550                         secrets.push([0; 32]);
1551                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1552                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone(), None).unwrap();
1553                         test_secrets!();
1554
1555                         secrets.push([0; 32]);
1556                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1557                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone(), None).unwrap();
1558                         test_secrets!();
1559
1560                         secrets.push([0; 32]);
1561                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1562                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone(), None).unwrap();
1563                         test_secrets!();
1564
1565                         secrets.push([0; 32]);
1566                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1567                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone(), None).unwrap();
1568                         test_secrets!();
1569
1570                         secrets.push([0; 32]);
1571                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("631373ad5f9ef654bb3dade742d09504c567edd24320d2fcd68e3cc47e2ff6a6").unwrap());
1572                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone(), None).unwrap();
1573                         test_secrets!();
1574
1575                         secrets.push([0; 32]);
1576                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("b7e76a83668bde38b373970155c868a653304308f9896692f904a23731224bb1").unwrap());
1577                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone(), None).unwrap();
1578                         test_secrets!();
1579
1580                         secrets.push([0; 32]);
1581                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
1582                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone(), None).unwrap();
1583                         test_secrets!();
1584
1585                         secrets.push([0; 32]);
1586                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
1587                         assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone(), None).unwrap_err().err,
1588                                         "Previous secret did not match new one");
1589                 }
1590
1591                 {
1592                         // insert_secret #7 incorrect
1593                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &delayed_payment_base_key, &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), 0, Script::new());
1594                         secrets.clear();
1595
1596                         secrets.push([0; 32]);
1597                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1598                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone(), None).unwrap();
1599                         test_secrets!();
1600
1601                         secrets.push([0; 32]);
1602                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1603                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone(), None).unwrap();
1604                         test_secrets!();
1605
1606                         secrets.push([0; 32]);
1607                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1608                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone(), None).unwrap();
1609                         test_secrets!();
1610
1611                         secrets.push([0; 32]);
1612                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1613                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone(), None).unwrap();
1614                         test_secrets!();
1615
1616                         secrets.push([0; 32]);
1617                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
1618                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone(), None).unwrap();
1619                         test_secrets!();
1620
1621                         secrets.push([0; 32]);
1622                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
1623                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone(), None).unwrap();
1624                         test_secrets!();
1625
1626                         secrets.push([0; 32]);
1627                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("e7971de736e01da8ed58b94c2fc216cb1dca9e326f3a96e7194fe8ea8af6c0a3").unwrap());
1628                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone(), None).unwrap();
1629                         test_secrets!();
1630
1631                         secrets.push([0; 32]);
1632                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
1633                         assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone(), None).unwrap_err().err,
1634                                         "Previous secret did not match new one");
1635                 }
1636
1637                 {
1638                         // insert_secret #8 incorrect
1639                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &delayed_payment_base_key, &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), 0, Script::new());
1640                         secrets.clear();
1641
1642                         secrets.push([0; 32]);
1643                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1644                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone(), None).unwrap();
1645                         test_secrets!();
1646
1647                         secrets.push([0; 32]);
1648                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1649                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone(), None).unwrap();
1650                         test_secrets!();
1651
1652                         secrets.push([0; 32]);
1653                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1654                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone(), None).unwrap();
1655                         test_secrets!();
1656
1657                         secrets.push([0; 32]);
1658                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1659                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone(), None).unwrap();
1660                         test_secrets!();
1661
1662                         secrets.push([0; 32]);
1663                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
1664                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone(), None).unwrap();
1665                         test_secrets!();
1666
1667                         secrets.push([0; 32]);
1668                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
1669                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone(), None).unwrap();
1670                         test_secrets!();
1671
1672                         secrets.push([0; 32]);
1673                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
1674                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone(), None).unwrap();
1675                         test_secrets!();
1676
1677                         secrets.push([0; 32]);
1678                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a7efbc61aac46d34f77778bac22c8a20c6a46ca460addc49009bda875ec88fa4").unwrap());
1679                         assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone(), None).unwrap_err().err,
1680                                         "Previous secret did not match new one");
1681                 }
1682         }
1683
1684         #[test]
1685         fn test_prune_preimages() {
1686                 let secp_ctx = Secp256k1::new();
1687                 let dummy_sig = Signature::from_der(&secp_ctx, &hex::decode("3045022100fa86fa9a36a8cd6a7bb8f06a541787d51371d067951a9461d5404de6b928782e02201c8b7c334c10aed8976a3a465be9a28abff4cb23acbf00022295b378ce1fa3cd").unwrap()[..]).unwrap();
1688
1689                 macro_rules! dummy_keys {
1690                         () => {
1691                                 {
1692                                         let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap());
1693                                         TxCreationKeys {
1694                                                 per_commitment_point: dummy_key.clone(),
1695                                                 revocation_key: dummy_key.clone(),
1696                                                 a_htlc_key: dummy_key.clone(),
1697                                                 b_htlc_key: dummy_key.clone(),
1698                                                 a_delayed_payment_key: dummy_key.clone(),
1699                                                 b_payment_key: dummy_key.clone(),
1700                                         }
1701                                 }
1702                         }
1703                 }
1704                 let dummy_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
1705
1706                 let mut preimages = Vec::new();
1707                 {
1708                         let mut rng  = thread_rng();
1709                         for _ in 0..20 {
1710                                 let mut preimage = [0; 32];
1711                                 rng.fill_bytes(&mut preimage);
1712                                 let mut sha = Sha256::new();
1713                                 sha.input(&preimage);
1714                                 let mut hash = [0; 32];
1715                                 sha.result(&mut hash);
1716                                 preimages.push((preimage, hash));
1717                         }
1718                 }
1719
1720                 macro_rules! preimages_slice_to_htlc_outputs {
1721                         ($preimages_slice: expr) => {
1722                                 {
1723                                         let mut res = Vec::new();
1724                                         for (idx, preimage) in $preimages_slice.iter().enumerate() {
1725                                                 res.push(HTLCOutputInCommitment {
1726                                                         offered: true,
1727                                                         amount_msat: 0,
1728                                                         cltv_expiry: 0,
1729                                                         payment_hash: preimage.1.clone(),
1730                                                         transaction_output_index: idx as u32,
1731                                                 });
1732                                         }
1733                                         res
1734                                 }
1735                         }
1736                 }
1737                 macro_rules! preimages_to_local_htlcs {
1738                         ($preimages_slice: expr) => {
1739                                 {
1740                                         let mut inp = preimages_slice_to_htlc_outputs!($preimages_slice);
1741                                         let res: Vec<_> = inp.drain(..).map(|e| { (e, dummy_sig.clone(), dummy_sig.clone()) }).collect();
1742                                         res
1743                                 }
1744                         }
1745                 }
1746
1747                 macro_rules! test_preimages_exist {
1748                         ($preimages_slice: expr, $monitor: expr) => {
1749                                 for preimage in $preimages_slice {
1750                                         assert!($monitor.payment_preimages.contains_key(&preimage.1));
1751                                 }
1752                         }
1753                 }
1754
1755                 // Prune with one old state and a local commitment tx holding a few overlaps with the
1756                 // old state.
1757                 let delayed_payment_base_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap());
1758                 let mut monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &delayed_payment_base_key, &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), 0, Script::new());
1759                 monitor.set_their_to_self_delay(10);
1760
1761                 monitor.provide_latest_local_commitment_tx_info(dummy_tx.clone(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..10]));
1762                 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[5..15]), 281474976710655);
1763                 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[15..20]), 281474976710654);
1764                 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[17..20]), 281474976710653);
1765                 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[18..20]), 281474976710652);
1766                 for &(ref preimage, ref hash) in preimages.iter() {
1767                         monitor.provide_payment_preimage(hash, preimage);
1768                 }
1769
1770                 // Now provide a secret, pruning preimages 10-15
1771                 let mut secret = [0; 32];
1772                 secret[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1773                 monitor.provide_secret(281474976710655, secret.clone(), None).unwrap();
1774                 assert_eq!(monitor.payment_preimages.len(), 15);
1775                 test_preimages_exist!(&preimages[0..10], monitor);
1776                 test_preimages_exist!(&preimages[15..20], monitor);
1777
1778                 // Now provide a further secret, pruning preimages 15-17
1779                 secret[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1780                 monitor.provide_secret(281474976710654, secret.clone(), None).unwrap();
1781                 assert_eq!(monitor.payment_preimages.len(), 13);
1782                 test_preimages_exist!(&preimages[0..10], monitor);
1783                 test_preimages_exist!(&preimages[17..20], monitor);
1784
1785                 // Now update local commitment tx info, pruning only element 18 as we still care about the
1786                 // previous commitment tx's preimages too
1787                 monitor.provide_latest_local_commitment_tx_info(dummy_tx.clone(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..5]));
1788                 secret[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1789                 monitor.provide_secret(281474976710653, secret.clone(), None).unwrap();
1790                 assert_eq!(monitor.payment_preimages.len(), 12);
1791                 test_preimages_exist!(&preimages[0..10], monitor);
1792                 test_preimages_exist!(&preimages[18..20], monitor);
1793
1794                 // But if we do it again, we'll prune 5-10
1795                 monitor.provide_latest_local_commitment_tx_info(dummy_tx.clone(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..3]));
1796                 secret[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1797                 monitor.provide_secret(281474976710652, secret.clone(), None).unwrap();
1798                 assert_eq!(monitor.payment_preimages.len(), 5);
1799                 test_preimages_exist!(&preimages[0..5], monitor);
1800         }
1801
1802         // Further testing is done in the ChannelManager integration tests.
1803 }