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

   1 //! The logic to monitor for on-chain transactions and create the relevant claim responses lives
   2 //! here.
   3 //!
   4 //! ChannelMonitor objects are generated by ChannelManager in response to relevant
   5 //! messages/actions, and MUST be persisted to disk (and, preferably, remotely) before progress can
   6 //! be made in responding to certain messages, see ManyChannelMonitor for more.
   7 //!
   8 //! Note that ChannelMonitors are an important part of the lightning trust model and a copy of the
   9 //! latest ChannelMonitor must always be actively monitoring for chain updates (and no out-of-date
  10 //! ChannelMonitors should do so). Thus, if you're building rust-lightning into an HSM or other
  11 //! security-domain-separated system design, you should consider having multiple paths for
  12 //! ChannelMonitors to get out of the HSM and onto monitoring devices.
  13
  14 use bitcoin::blockdata::block::BlockHeader;
  15 use bitcoin::blockdata::transaction::{TxIn,TxOut,SigHashType,Transaction};
  16 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
  17 use bitcoin::blockdata::script::Script;
  18 use bitcoin::consensus::encode::{self, Decodable, Encodable};
  19 use bitcoin::util::hash::{BitcoinHash,Sha256dHash};
  20 use bitcoin::util::bip143;
  21
  22 use crypto::digest::Digest;
  23
  24 use secp256k1::{Secp256k1,Message,Signature};
  25 use secp256k1::key::{SecretKey,PublicKey};
  26 use secp256k1;
  27
  28 use ln::msgs::{DecodeError, HandleError};
  29 use ln::chan_utils;
  30 use ln::chan_utils::HTLCOutputInCommitment;
  31 use chain::chaininterface::{ChainListener, ChainWatchInterface, BroadcasterInterface};
  32 use chain::transaction::OutPoint;
  33 use chain::keysinterface::SpendableOutputDescriptor;
  34 use util::logger::Logger;
  35 use util::ser::{ReadableArgs, Readable, Writer, Writeable, WriterWriteAdaptor, U48};
  36 use util::sha2::Sha256;
  37 use util::{byte_utils, events};
  38
  39 use std::collections::HashMap;
  40 use std::sync::{Arc,Mutex};
  41 use std::{hash,cmp, mem};
  42
  43 /// An error enum representing a failure to persist a channel monitor update.
  44 #[derive(Clone)]
  45 pub enum ChannelMonitorUpdateErr {
  46         /// Used to indicate a temporary failure (eg connection to a watchtower failed, but is expected
  47         /// to succeed at some point in the future).
  48         ///
  49         /// Such a failure will "freeze" a channel, preventing us from revoking old states or
  50         /// submitting new commitment transactions to the remote party.
  51         /// ChannelManager::test_restore_channel_monitor can be used to retry the update(s) and restore
  52         /// the channel to an operational state.
  53         ///
  54         /// Note that continuing to operate when no copy of the updated ChannelMonitor could be
  55         /// persisted is unsafe - if you failed to store the update on your own local disk you should
  56         /// instead return PermanentFailure to force closure of the channel ASAP.
  57         ///
  58         /// Even when a channel has been "frozen" updates to the ChannelMonitor can continue to occur
  59         /// (eg if an inbound HTLC which we forwarded was claimed upstream resulting in us attempting
  60         /// to claim it on this channel) and those updates must be applied wherever they can be. At
  61         /// least one such updated ChannelMonitor must be persisted otherwise PermanentFailure should
  62         /// be returned to get things on-chain ASAP using only the in-memory copy. Obviously updates to
  63         /// the channel which would invalidate previous ChannelMonitors are not made when a channel has
  64         /// been "frozen".
  65         ///
  66         /// Note that even if updates made after TemporaryFailure succeed you must still call
  67         /// test_restore_channel_monitor to ensure you have the latest monitor and re-enable normal
  68         /// channel operation.
  69         TemporaryFailure,
  70         /// Used to indicate no further channel monitor updates will be allowed (eg we've moved on to a
  71         /// different watchtower and cannot update with all watchtowers that were previously informed
  72         /// of this channel). This will force-close the channel in question.
  73         PermanentFailure,
  74 }
  75
  76 /// Simple trait indicating ability to track a set of ChannelMonitors and multiplex events between
  77 /// them. Generally should be implemented by keeping a local SimpleManyChannelMonitor and passing
  78 /// events to it, while also taking any add_update_monitor events and passing them to some remote
  79 /// server(s).
  80 ///
  81 /// Note that any updates to a channel's monitor *must* be applied to each instance of the
  82 /// channel's monitor everywhere (including remote watchtowers) *before* this function returns. If
  83 /// an update occurs and a remote watchtower is left with old state, it may broadcast transactions
  84 /// which we have revoked, allowing our counterparty to claim all funds in the channel!
  85 pub trait ManyChannelMonitor: Send + Sync {
  86         /// Adds or updates a monitor for the given `funding_txo`.
  87         ///
  88         /// Implementor must also ensure that the funding_txo outpoint is registered with any relevant
  89         /// ChainWatchInterfaces such that the provided monitor receives block_connected callbacks with
  90         /// any spends of it.
  91         fn add_update_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor) -> Result<(), ChannelMonitorUpdateErr>;
  92 }
  93
  94 /// A simple implementation of a ManyChannelMonitor and ChainListener. Can be used to create a
  95 /// watchtower or watch our own channels.
  96 ///
  97 /// Note that you must provide your own key by which to refer to channels.
  98 ///
  99 /// If you're accepting remote monitors (ie are implementing a watchtower), you must verify that
 100 /// users cannot overwrite a given channel by providing a duplicate key. ie you should probably
 101 /// index by a PublicKey which is required to sign any updates.
 102 ///
 103 /// If you're using this for local monitoring of your own channels, you probably want to use
 104 /// `OutPoint` as the key, which will give you a ManyChannelMonitor implementation.
 105 pub struct SimpleManyChannelMonitor<Key> {
 106         #[cfg(test)] // Used in ChannelManager tests to manipulate channels directly
 107         pub monitors: Mutex<HashMap<Key, ChannelMonitor>>,
 108         #[cfg(not(test))]
 109         monitors: Mutex<HashMap<Key, ChannelMonitor>>,
 110         chain_monitor: Arc<ChainWatchInterface>,
 111         broadcaster: Arc<BroadcasterInterface>,
 112         pending_events: Mutex<Vec<events::Event>>,
 113         logger: Arc<Logger>,
 114 }
 115
 116 impl<Key : Send + cmp::Eq + hash::Hash> ChainListener for SimpleManyChannelMonitor<Key> {
 117         fn block_connected(&self, header: &BlockHeader, height: u32, txn_matched: &[&Transaction], _indexes_of_txn_matched: &[u32]) {
 118                 let block_hash = header.bitcoin_hash();
 119                 let mut new_events: Vec<events::Event> = Vec::with_capacity(0);
 120                 {
 121                         let mut monitors = self.monitors.lock().unwrap();
 122                         for monitor in monitors.values_mut() {
 123                                 let (txn_outputs, spendable_outputs) = monitor.block_connected(txn_matched, height, &block_hash, &*self.broadcaster);
 124                                 if spendable_outputs.len() > 0 {
 125                                         new_events.push(events::Event::SpendableOutputs {
 126                                                 outputs: spendable_outputs,
 127                                         });
 128                                 }
 129                                 for (ref txid, ref outputs) in txn_outputs {
 130                                         for (idx, output) in outputs.iter().enumerate() {
 131                                                 self.chain_monitor.install_watch_outpoint((txid.clone(), idx as u32), &output.script_pubkey);
 132                                         }
 133                                 }
 134                         }
 135                 }
 136                 let mut pending_events = self.pending_events.lock().unwrap();
 137                 pending_events.append(&mut new_events);
 138         }
 139
 140         fn block_disconnected(&self, _: &BlockHeader) { }
 141 }
 142
 143 impl<Key : Send + cmp::Eq + hash::Hash + 'static> SimpleManyChannelMonitor<Key> {
 144         /// Creates a new object which can be used to monitor several channels given the chain
 145         /// interface with which to register to receive notifications.
 146         pub fn new(chain_monitor: Arc<ChainWatchInterface>, broadcaster: Arc<BroadcasterInterface>, logger: Arc<Logger>) -> Arc<SimpleManyChannelMonitor<Key>> {
 147                 let res = Arc::new(SimpleManyChannelMonitor {
 148                         monitors: Mutex::new(HashMap::new()),
 149                         chain_monitor,
 150                         broadcaster,
 151                         pending_events: Mutex::new(Vec::new()),
 152                         logger,
 153                 });
 154                 let weak_res = Arc::downgrade(&res);
 155                 res.chain_monitor.register_listener(weak_res);
 156                 res
 157         }
 158
 159         /// Adds or udpates the monitor which monitors the channel referred to by the given key.
 160         pub fn add_update_monitor_by_key(&self, key: Key, monitor: ChannelMonitor) -> Result<(), HandleError> {
 161                 let mut monitors = self.monitors.lock().unwrap();
 162                 match monitors.get_mut(&key) {
 163                         Some(orig_monitor) => {
 164                                 log_trace!(self, "Updating Channel Monitor for channel {}", log_funding_option!(monitor.funding_txo));
 165                                 return orig_monitor.insert_combine(monitor);
 166                         },
 167                         None => {}
 168                 };
 169                 match &monitor.funding_txo {
 170                         &None => {
 171                                 log_trace!(self, "Got new Channel Monitor for no-funding-set channel (monitoring all txn!)");
 172                                 self.chain_monitor.watch_all_txn()
 173                         },
 174                         &Some((ref outpoint, ref script)) => {
 175                                 log_trace!(self, "Got new Channel Monitor for channel {}", log_bytes!(outpoint.to_channel_id()[..]));
 176                                 self.chain_monitor.install_watch_tx(&outpoint.txid, script);
 177                                 self.chain_monitor.install_watch_outpoint((outpoint.txid, outpoint.index as u32), script);
 178                         },
 179                 }
 180                 monitors.insert(key, monitor);
 181                 Ok(())
 182         }
 183 }
 184
 185 impl ManyChannelMonitor for SimpleManyChannelMonitor<OutPoint> {
 186         fn add_update_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor) -> Result<(), ChannelMonitorUpdateErr> {
 187                 match self.add_update_monitor_by_key(funding_txo, monitor) {
 188                         Ok(_) => Ok(()),
 189                         Err(_) => Err(ChannelMonitorUpdateErr::PermanentFailure),
 190                 }
 191         }
 192 }
 193
 194 impl<Key : Send + cmp::Eq + hash::Hash> events::EventsProvider for SimpleManyChannelMonitor<Key> {
 195         fn get_and_clear_pending_events(&self) -> Vec<events::Event> {
 196                 let mut pending_events = self.pending_events.lock().unwrap();
 197                 let mut ret = Vec::new();
 198                 mem::swap(&mut ret, &mut *pending_events);
 199                 ret
 200         }
 201 }
 202
 203 /// If an HTLC expires within this many blocks, don't try to claim it in a shared transaction,
 204 /// instead claiming it in its own individual transaction.
 205 const CLTV_SHARED_CLAIM_BUFFER: u32 = 12;
 206 /// If an HTLC expires within this many blocks, force-close the channel to broadcast the
 207 /// HTLC-Success transaction.
 208 /// In other words, this is an upper bound on how many blocks we think it can take us to get a
 209 /// transaction confirmed (and we use it in a few more, equivalent, places).
 210 pub(crate) const CLTV_CLAIM_BUFFER: u32 = 6;
 211 /// Number of blocks by which point we expect our counterparty to have seen new blocks on the
 212 /// network and done a full update_fail_htlc/commitment_signed dance (+ we've updated all our
 213 /// copies of ChannelMonitors, including watchtowers).
 214 pub(crate) const HTLC_FAIL_TIMEOUT_BLOCKS: u32 = 3;
 215
 216 #[derive(Clone, PartialEq)]
 217 enum KeyStorage {
 218         PrivMode {
 219                 revocation_base_key: SecretKey,
 220                 htlc_base_key: SecretKey,
 221                 delayed_payment_base_key: SecretKey,
 222                 prev_latest_per_commitment_point: Option<PublicKey>,
 223                 latest_per_commitment_point: Option<PublicKey>,
 224         },
 225         SigsMode {
 226                 revocation_base_key: PublicKey,
 227                 htlc_base_key: PublicKey,
 228                 sigs: HashMap<Sha256dHash, Signature>,
 229         }
 230 }
 231
 232 #[derive(Clone, PartialEq)]
 233 struct LocalSignedTx {
 234         /// txid of the transaction in tx, just used to make comparison faster
 235         txid: Sha256dHash,
 236         tx: Transaction,
 237         revocation_key: PublicKey,
 238         a_htlc_key: PublicKey,
 239         b_htlc_key: PublicKey,
 240         delayed_payment_key: PublicKey,
 241         feerate_per_kw: u64,
 242         htlc_outputs: Vec<(HTLCOutputInCommitment, Signature, Signature)>,
 243 }
 244
 245 const SERIALIZATION_VERSION: u8 = 1;
 246 const MIN_SERIALIZATION_VERSION: u8 = 1;
 247
 248 /// A ChannelMonitor handles chain events (blocks connected and disconnected) and generates
 249 /// on-chain transactions to ensure no loss of funds occurs.
 250 ///
 251 /// You MUST ensure that no ChannelMonitors for a given channel anywhere contain out-of-date
 252 /// information and are actively monitoring the chain.
 253 #[derive(Clone)]
 254 pub struct ChannelMonitor {
 255         funding_txo: Option<(OutPoint, Script)>,
 256         commitment_transaction_number_obscure_factor: u64,
 257
 258         key_storage: KeyStorage,
 259         their_htlc_base_key: Option<PublicKey>,
 260         their_delayed_payment_base_key: Option<PublicKey>,
 261         // first is the idx of the first of the two revocation points
 262         their_cur_revocation_points: Option<(u64, PublicKey, Option<PublicKey>)>,
 263
 264         our_to_self_delay: u16,
 265         their_to_self_delay: Option<u16>,
 266
 267         old_secrets: [([u8; 32], u64); 49],
 268         remote_claimable_outpoints: HashMap<Sha256dHash, Vec<HTLCOutputInCommitment>>,
 269         /// We cannot identify HTLC-Success or HTLC-Timeout transactions by themselves on the chain.
 270         /// Nor can we figure out their commitment numbers without the commitment transaction they are
 271         /// spending. Thus, in order to claim them via revocation key, we track all the remote
 272         /// commitment transactions which we find on-chain, mapping them to the commitment number which
 273         /// can be used to derive the revocation key and claim the transactions.
 274         remote_commitment_txn_on_chain: HashMap<Sha256dHash, (u64, Vec<Script>)>,
 275         /// Cache used to make pruning of payment_preimages faster.
 276         /// Maps payment_hash values to commitment numbers for remote transactions for non-revoked
 277         /// remote transactions (ie should remain pretty small).
 278         /// Serialized to disk but should generally not be sent to Watchtowers.
 279         remote_hash_commitment_number: HashMap<[u8; 32], u64>,
 280
 281         // We store two local commitment transactions to avoid any race conditions where we may update
 282         // some monitors (potentially on watchtowers) but then fail to update others, resulting in the
 283         // various monitors for one channel being out of sync, and us broadcasting a local
 284         // transaction for which we have deleted claim information on some watchtowers.
 285         prev_local_signed_commitment_tx: Option<LocalSignedTx>,
 286         current_local_signed_commitment_tx: Option<LocalSignedTx>,
 287
 288         // Used just for ChannelManager to make sure it has the latest channel data during
 289         // deserialization
 290         current_remote_commitment_number: u64,
 291
 292         payment_preimages: HashMap<[u8; 32], [u8; 32]>,
 293
 294         destination_script: Script,
 295
 296         // We simply modify last_block_hash in Channel's block_connected so that serialization is
 297         // consistent but hopefully the users' copy handles block_connected in a consistent way.
 298         // (we do *not*, however, update them in insert_combine to ensure any local user copies keep
 299         // their last_block_hash from its state and not based on updated copies that didn't run through
 300         // the full block_connected).
 301         pub(crate) last_block_hash: Sha256dHash,
 302         secp_ctx: Secp256k1<secp256k1::All>, //TODO: dedup this a bit...
 303         logger: Arc<Logger>,
 304 }
 305
 306 #[cfg(any(test, feature = "fuzztarget"))]
 307 /// Used only in testing and fuzztarget to check serialization roundtrips don't change the
 308 /// underlying object
 309 impl PartialEq for ChannelMonitor {
 310         fn eq(&self, other: &Self) -> bool {
 311                 if self.funding_txo != other.funding_txo ||
 312                         self.commitment_transaction_number_obscure_factor != other.commitment_transaction_number_obscure_factor ||
 313                         self.key_storage != other.key_storage ||
 314                         self.their_htlc_base_key != other.their_htlc_base_key ||
 315                         self.their_delayed_payment_base_key != other.their_delayed_payment_base_key ||
 316                         self.their_cur_revocation_points != other.their_cur_revocation_points ||
 317                         self.our_to_self_delay != other.our_to_self_delay ||
 318                         self.their_to_self_delay != other.their_to_self_delay ||
 319                         self.remote_claimable_outpoints != other.remote_claimable_outpoints ||
 320                         self.remote_commitment_txn_on_chain != other.remote_commitment_txn_on_chain ||
 321                         self.remote_hash_commitment_number != other.remote_hash_commitment_number ||
 322                         self.prev_local_signed_commitment_tx != other.prev_local_signed_commitment_tx ||
 323                         self.current_remote_commitment_number != other.current_remote_commitment_number ||
 324                         self.current_local_signed_commitment_tx != other.current_local_signed_commitment_tx ||
 325                         self.payment_preimages != other.payment_preimages ||
 326                         self.destination_script != other.destination_script
 327                 {
 328                         false
 329                 } else {
 330                         for (&(ref secret, ref idx), &(ref o_secret, ref o_idx)) in self.old_secrets.iter().zip(other.old_secrets.iter()) {
 331                                 if secret != o_secret || idx != o_idx {
 332                                         return false
 333                                 }
 334                         }
 335                         true
 336                 }
 337         }
 338 }
 339
 340 impl ChannelMonitor {
 341         pub(super) fn new(revocation_base_key: &SecretKey, delayed_payment_base_key: &SecretKey, htlc_base_key: &SecretKey, our_to_self_delay: u16, destination_script: Script, logger: Arc<Logger>) -> ChannelMonitor {
 342                 ChannelMonitor {
 343                         funding_txo: None,
 344                         commitment_transaction_number_obscure_factor: 0,
 345
 346                         key_storage: KeyStorage::PrivMode {
 347                                 revocation_base_key: revocation_base_key.clone(),
 348                                 htlc_base_key: htlc_base_key.clone(),
 349                                 delayed_payment_base_key: delayed_payment_base_key.clone(),
 350                                 prev_latest_per_commitment_point: None,
 351                                 latest_per_commitment_point: None,
 352                         },
 353                         their_htlc_base_key: None,
 354                         their_delayed_payment_base_key: None,
 355                         their_cur_revocation_points: None,
 356
 357                         our_to_self_delay: our_to_self_delay,
 358                         their_to_self_delay: None,
 359
 360                         old_secrets: [([0; 32], 1 << 48); 49],
 361                         remote_claimable_outpoints: HashMap::new(),
 362                         remote_commitment_txn_on_chain: HashMap::new(),
 363                         remote_hash_commitment_number: HashMap::new(),
 364
 365                         prev_local_signed_commitment_tx: None,
 366                         current_local_signed_commitment_tx: None,
 367                         current_remote_commitment_number: 1 << 48,
 368
 369                         payment_preimages: HashMap::new(),
 370                         destination_script: destination_script,
 371
 372                         last_block_hash: Default::default(),
 373                         secp_ctx: Secp256k1::new(),
 374                         logger,
 375                 }
 376         }
 377
 378         #[inline]
 379         fn place_secret(idx: u64) -> u8 {
 380                 for i in 0..48 {
 381                         if idx & (1 << i) == (1 << i) {
 382                                 return i
 383                         }
 384                 }
 385                 48
 386         }
 387
 388         #[inline]
 389         fn derive_secret(secret: [u8; 32], bits: u8, idx: u64) -> [u8; 32] {
 390                 let mut res: [u8; 32] = secret;
 391                 for i in 0..bits {
 392                         let bitpos = bits - 1 - i;
 393                         if idx & (1 << bitpos) == (1 << bitpos) {
 394                                 res[(bitpos / 8) as usize] ^= 1 << (bitpos & 7);
 395                                 let mut sha = Sha256::new();
 396                                 sha.input(&res);
 397                                 sha.result(&mut res);
 398                         }
 399                 }
 400                 res
 401         }
 402
 403         /// Inserts a revocation secret into this channel monitor. Prunes old preimages if neither
 404         /// needed by local commitment transactions HTCLs nor by remote ones. Unless we haven't already seen remote
 405         /// commitment transaction's secret, they are de facto pruned (we can use revocation key).
 406         pub(super) fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), HandleError> {
 407                 let pos = ChannelMonitor::place_secret(idx);
 408                 for i in 0..pos {
 409                         let (old_secret, old_idx) = self.old_secrets[i as usize];
 410                         if ChannelMonitor::derive_secret(secret, pos, old_idx) != old_secret {
 411                                 return Err(HandleError{err: "Previous secret did not match new one", action: None})
 412                         }
 413                 }
 414                 self.old_secrets[pos as usize] = (secret, idx);
 415
 416                 if !self.payment_preimages.is_empty() {
 417                         let local_signed_commitment_tx = self.current_local_signed_commitment_tx.as_ref().expect("Channel needs at least an initial commitment tx !");
 418                         let prev_local_signed_commitment_tx = self.prev_local_signed_commitment_tx.as_ref();
 419                         let min_idx = self.get_min_seen_secret();
 420                         let remote_hash_commitment_number = &mut self.remote_hash_commitment_number;
 421
 422                         self.payment_preimages.retain(|&k, _| {
 423                                 for &(ref htlc, _, _) in &local_signed_commitment_tx.htlc_outputs {
 424                                         if k == htlc.payment_hash {
 425                                                 return true
 426                                         }
 427                                 }
 428                                 if let Some(prev_local_commitment_tx) = prev_local_signed_commitment_tx {
 429                                         for &(ref htlc, _, _) in prev_local_commitment_tx.htlc_outputs.iter() {
 430                                                 if k == htlc.payment_hash {
 431                                                         return true
 432                                                 }
 433                                         }
 434                                 }
 435                                 let contains = if let Some(cn) = remote_hash_commitment_number.get(&k) {
 436                                         if *cn < min_idx {
 437                                                 return true
 438                                         }
 439                                         true
 440                                 } else { false };
 441                                 if contains {
 442                                         remote_hash_commitment_number.remove(&k);
 443                                 }
 444                                 false
 445                         });
 446                 }
 447
 448                 Ok(())
 449         }
 450
 451         /// Tracks the next revocation point which may be required to claim HTLC outputs which we know
 452         /// the preimage of in case the remote end force-closes using their latest state. When called at
 453         /// channel opening revocation point is the CURRENT one used for first commitment tx. Needed in case of sizeable push_msat.
 454         pub(super) fn provide_their_next_revocation_point(&mut self, their_next_revocation_point: Option<(u64, PublicKey)>) {
 455                 if let Some(new_revocation_point) = their_next_revocation_point {
 456                         match self.their_cur_revocation_points {
 457                                 Some(old_points) => {
 458                                         if old_points.0 == new_revocation_point.0 + 1 {
 459                                                 self.their_cur_revocation_points = Some((old_points.0, old_points.1, Some(new_revocation_point.1)));
 460                                         } else if old_points.0 == new_revocation_point.0 + 2 {
 461                                                 if let Some(old_second_point) = old_points.2 {
 462                                                         self.their_cur_revocation_points = Some((old_points.0 - 1, old_second_point, Some(new_revocation_point.1)));
 463                                                 } else {
 464                                                         self.their_cur_revocation_points = Some((new_revocation_point.0, new_revocation_point.1, None));
 465                                                 }
 466                                         } else {
 467                                                 self.their_cur_revocation_points = Some((new_revocation_point.0, new_revocation_point.1, None));
 468                                         }
 469                                 },
 470                                 None => {
 471                                         self.their_cur_revocation_points = Some((new_revocation_point.0, new_revocation_point.1, None));
 472                                 }
 473                         }
 474                 }
 475         }
 476
 477         /// Informs this monitor of the latest remote (ie non-broadcastable) commitment transaction.
 478         /// The monitor watches for it to be broadcasted and then uses the HTLC information (and
 479         /// possibly future revocation/preimage information) to claim outputs where possible.
 480         /// We cache also the mapping hash:commitment number to lighten pruning of old preimages by watchtowers.
 481         pub(super) fn provide_latest_remote_commitment_tx_info(&mut self, unsigned_commitment_tx: &Transaction, htlc_outputs: Vec<HTLCOutputInCommitment>, commitment_number: u64) {
 482                 // TODO: Encrypt the htlc_outputs data with the single-hash of the commitment transaction
 483                 // so that a remote monitor doesn't learn anything unless there is a malicious close.
 484                 // (only maybe, sadly we cant do the same for local info, as we need to be aware of
 485                 // timeouts)
 486                 for htlc in &htlc_outputs {
 487                         self.remote_hash_commitment_number.insert(htlc.payment_hash, commitment_number);
 488                 }
 489                 self.remote_claimable_outpoints.insert(unsigned_commitment_tx.txid(), htlc_outputs);
 490                 self.current_remote_commitment_number = commitment_number;
 491         }
 492
 493         /// Informs this monitor of the latest local (ie broadcastable) commitment transaction. The
 494         /// monitor watches for timeouts and may broadcast it if we approach such a timeout. Thus, it
 495         /// is important that any clones of this channel monitor (including remote clones) by kept
 496         /// up-to-date as our local commitment transaction is updated.
 497         /// Panics if set_their_to_self_delay has never been called.
 498         /// Also update KeyStorage with latest local per_commitment_point to derive local_delayedkey in
 499         /// case of onchain HTLC tx
 500         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)>) {
 501                 assert!(self.their_to_self_delay.is_some());
 502                 self.prev_local_signed_commitment_tx = self.current_local_signed_commitment_tx.take();
 503                 self.current_local_signed_commitment_tx = Some(LocalSignedTx {
 504                         txid: signed_commitment_tx.txid(),
 505                         tx: signed_commitment_tx,
 506                         revocation_key: local_keys.revocation_key,
 507                         a_htlc_key: local_keys.a_htlc_key,
 508                         b_htlc_key: local_keys.b_htlc_key,
 509                         delayed_payment_key: local_keys.a_delayed_payment_key,
 510                         feerate_per_kw,
 511                         htlc_outputs,
 512                 });
 513                 self.key_storage = if let KeyStorage::PrivMode { ref revocation_base_key, ref htlc_base_key, ref delayed_payment_base_key, prev_latest_per_commitment_point: _, ref latest_per_commitment_point } = self.key_storage {
 514                         KeyStorage::PrivMode {
 515                                 revocation_base_key: *revocation_base_key,
 516                                 htlc_base_key: *htlc_base_key,
 517                                 delayed_payment_base_key: *delayed_payment_base_key,
 518                                 prev_latest_per_commitment_point: *latest_per_commitment_point,
 519                                 latest_per_commitment_point: Some(local_keys.per_commitment_point),
 520                         }
 521                 } else { unimplemented!(); };
 522         }
 523
 524         /// Provides a payment_hash->payment_preimage mapping. Will be automatically pruned when all
 525         /// commitment_tx_infos which contain the payment hash have been revoked.
 526         pub(super) fn provide_payment_preimage(&mut self, payment_hash: &[u8; 32], payment_preimage: &[u8; 32]) {
 527                 self.payment_preimages.insert(payment_hash.clone(), payment_preimage.clone());
 528         }
 529
 530         /// Combines this ChannelMonitor with the information contained in the other ChannelMonitor.
 531         /// After a successful call this ChannelMonitor is up-to-date and is safe to use to monitor the
 532         /// chain for new blocks/transactions.
 533         pub fn insert_combine(&mut self, mut other: ChannelMonitor) -> Result<(), HandleError> {
 534                 if self.funding_txo.is_some() {
 535                         // We should be able to compare the entire funding_txo, but in fuzztarget its trivially
 536                         // easy to collide the funding_txo hash and have a different scriptPubKey.
 537                         if other.funding_txo.is_some() && other.funding_txo.as_ref().unwrap().0 != self.funding_txo.as_ref().unwrap().0 {
 538                                 return Err(HandleError{err: "Funding transaction outputs are not identical!", action: None});
 539                         }
 540                 } else {
 541                         self.funding_txo = other.funding_txo.take();
 542                 }
 543                 let other_min_secret = other.get_min_seen_secret();
 544                 let our_min_secret = self.get_min_seen_secret();
 545                 if our_min_secret > other_min_secret {
 546                         self.provide_secret(other_min_secret, other.get_secret(other_min_secret).unwrap())?;
 547                 }
 548                 // TODO: We should use current_remote_commitment_number and the commitment number out of
 549                 // local transactions to decide how to merge
 550                 if our_min_secret >= other_min_secret {
 551                         self.their_cur_revocation_points = other.their_cur_revocation_points;
 552                         for (txid, htlcs) in other.remote_claimable_outpoints.drain() {
 553                                 self.remote_claimable_outpoints.insert(txid, htlcs);
 554                         }
 555                         if let Some(local_tx) = other.prev_local_signed_commitment_tx {
 556                                 self.prev_local_signed_commitment_tx = Some(local_tx);
 557                         }
 558                         if let Some(local_tx) = other.current_local_signed_commitment_tx {
 559                                 self.current_local_signed_commitment_tx = Some(local_tx);
 560                         }
 561                         self.payment_preimages = other.payment_preimages;
 562                 }
 563                 self.current_remote_commitment_number = cmp::min(self.current_remote_commitment_number, other.current_remote_commitment_number);
 564                 Ok(())
 565         }
 566
 567         /// Panics if commitment_transaction_number_obscure_factor doesn't fit in 48 bits
 568         pub(super) fn set_commitment_obscure_factor(&mut self, commitment_transaction_number_obscure_factor: u64) {
 569                 assert!(commitment_transaction_number_obscure_factor < (1 << 48));
 570                 self.commitment_transaction_number_obscure_factor = commitment_transaction_number_obscure_factor;
 571         }
 572
 573         /// Allows this monitor to scan only for transactions which are applicable. Note that this is
 574         /// optional, without it this monitor cannot be used in an SPV client, but you may wish to
 575         /// avoid this (or call unset_funding_info) on a monitor you wish to send to a watchtower as it
 576         /// provides slightly better privacy.
 577         /// It's the responsibility of the caller to register outpoint and script with passing the former
 578         /// value as key to add_update_monitor.
 579         pub(super) fn set_funding_info(&mut self, funding_info: (OutPoint, Script)) {
 580                 self.funding_txo = Some(funding_info);
 581         }
 582
 583         /// We log these base keys at channel opening to being able to rebuild redeemscript in case of leaked revoked commit tx
 584         pub(super) fn set_their_base_keys(&mut self, their_htlc_base_key: &PublicKey, their_delayed_payment_base_key: &PublicKey) {
 585                 self.their_htlc_base_key = Some(their_htlc_base_key.clone());
 586                 self.their_delayed_payment_base_key = Some(their_delayed_payment_base_key.clone());
 587         }
 588
 589         pub(super) fn set_their_to_self_delay(&mut self, their_to_self_delay: u16) {
 590                 self.their_to_self_delay = Some(their_to_self_delay);
 591         }
 592
 593         pub(super) fn unset_funding_info(&mut self) {
 594                 self.funding_txo = None;
 595         }
 596
 597         /// Gets the funding transaction outpoint of the channel this ChannelMonitor is monitoring for.
 598         pub fn get_funding_txo(&self) -> Option<OutPoint> {
 599                 match self.funding_txo {
 600                         Some((outpoint, _)) => Some(outpoint),
 601                         None => None
 602                 }
 603         }
 604
 605         /// Gets the sets of all outpoints which this ChannelMonitor expects to hear about spends of.
 606         /// Generally useful when deserializing as during normal operation the return values of
 607         /// block_connected are sufficient to ensure all relevant outpoints are being monitored (note
 608         /// that the get_funding_txo outpoint and transaction must also be monitored for!).
 609         pub fn get_monitored_outpoints(&self) -> Vec<(Sha256dHash, u32, &Script)> {
 610                 let mut res = Vec::with_capacity(self.remote_commitment_txn_on_chain.len() * 2);
 611                 for (ref txid, &(_, ref outputs)) in self.remote_commitment_txn_on_chain.iter() {
 612                         for (idx, output) in outputs.iter().enumerate() {
 613                                 res.push(((*txid).clone(), idx as u32, output));
 614                         }
 615                 }
 616                 res
 617         }
 618
 619         /// Serializes into a vec, with various modes for the exposed pub fns
 620         fn write<W: Writer>(&self, writer: &mut W, for_local_storage: bool) -> Result<(), ::std::io::Error> {
 621                 //TODO: We still write out all the serialization here manually instead of using the fancy
 622                 //serialization framework we have, we should migrate things over to it.
 623                 writer.write_all(&[SERIALIZATION_VERSION; 1])?;
 624                 writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
 625
 626                 match &self.funding_txo {
 627                         &Some((ref outpoint, ref script)) => {
 628                                 writer.write_all(&outpoint.txid[..])?;
 629                                 writer.write_all(&byte_utils::be16_to_array(outpoint.index))?;
 630                                 script.write(writer)?;
 631                         },
 632                         &None => {
 633                                 // We haven't even been initialized...not sure why anyone is serializing us, but
 634                                 // not much to give them.
 635                                 return Ok(());
 636                         },
 637                 }
 638
 639                 // Set in initial Channel-object creation, so should always be set by now:
 640                 U48(self.commitment_transaction_number_obscure_factor).write(writer)?;
 641
 642                 match self.key_storage {
 643                         KeyStorage::PrivMode { ref revocation_base_key, ref htlc_base_key, ref delayed_payment_base_key, ref prev_latest_per_commitment_point, ref latest_per_commitment_point } => {
 644                                 writer.write_all(&[0; 1])?;
 645                                 writer.write_all(&revocation_base_key[..])?;
 646                                 writer.write_all(&htlc_base_key[..])?;
 647                                 writer.write_all(&delayed_payment_base_key[..])?;
 648                                 if let Some(ref prev_latest_per_commitment_point) = *prev_latest_per_commitment_point {
 649                                         writer.write_all(&[1; 1])?;
 650                                         writer.write_all(&prev_latest_per_commitment_point.serialize())?;
 651                                 } else {
 652                                         writer.write_all(&[0; 1])?;
 653                                 }
 654                                 if let Some(ref latest_per_commitment_point) = *latest_per_commitment_point {
 655                                         writer.write_all(&[1; 1])?;
 656                                         writer.write_all(&latest_per_commitment_point.serialize())?;
 657                                 } else {
 658                                         writer.write_all(&[0; 1])?;
 659                                 }
 660
 661                         },
 662                         KeyStorage::SigsMode { .. } => unimplemented!(),
 663                 }
 664
 665                 writer.write_all(&self.their_htlc_base_key.as_ref().unwrap().serialize())?;
 666                 writer.write_all(&self.their_delayed_payment_base_key.as_ref().unwrap().serialize())?;
 667
 668                 match self.their_cur_revocation_points {
 669                         Some((idx, pubkey, second_option)) => {
 670                                 writer.write_all(&byte_utils::be48_to_array(idx))?;
 671                                 writer.write_all(&pubkey.serialize())?;
 672                                 match second_option {
 673                                         Some(second_pubkey) => {
 674                                                 writer.write_all(&second_pubkey.serialize())?;
 675                                         },
 676                                         None => {
 677                                                 writer.write_all(&[0; 33])?;
 678                                         },
 679                                 }
 680                         },
 681                         None => {
 682                                 writer.write_all(&byte_utils::be48_to_array(0))?;
 683                         },
 684                 }
 685
 686                 writer.write_all(&byte_utils::be16_to_array(self.our_to_self_delay))?;
 687                 writer.write_all(&byte_utils::be16_to_array(self.their_to_self_delay.unwrap()))?;
 688
 689                 for &(ref secret, ref idx) in self.old_secrets.iter() {
 690                         writer.write_all(secret)?;
 691                         writer.write_all(&byte_utils::be64_to_array(*idx))?;
 692                 }
 693
 694                 macro_rules! serialize_htlc_in_commitment {
 695                         ($htlc_output: expr) => {
 696                                 writer.write_all(&[$htlc_output.offered as u8; 1])?;
 697                                 writer.write_all(&byte_utils::be64_to_array($htlc_output.amount_msat))?;
 698                                 writer.write_all(&byte_utils::be32_to_array($htlc_output.cltv_expiry))?;
 699                                 writer.write_all(&$htlc_output.payment_hash)?;
 700                                 writer.write_all(&byte_utils::be32_to_array($htlc_output.transaction_output_index))?;
 701                         }
 702                 }
 703
 704                 writer.write_all(&byte_utils::be64_to_array(self.remote_claimable_outpoints.len() as u64))?;
 705                 for (ref txid, ref htlc_outputs) in self.remote_claimable_outpoints.iter() {
 706                         writer.write_all(&txid[..])?;
 707                         writer.write_all(&byte_utils::be64_to_array(htlc_outputs.len() as u64))?;
 708                         for htlc_output in htlc_outputs.iter() {
 709                                 serialize_htlc_in_commitment!(htlc_output);
 710                         }
 711                 }
 712
 713                 writer.write_all(&byte_utils::be64_to_array(self.remote_commitment_txn_on_chain.len() as u64))?;
 714                 for (ref txid, &(commitment_number, ref txouts)) in self.remote_commitment_txn_on_chain.iter() {
 715                         writer.write_all(&txid[..])?;
 716                         writer.write_all(&byte_utils::be48_to_array(commitment_number))?;
 717                         (txouts.len() as u64).write(writer)?;
 718                         for script in txouts.iter() {
 719                                 script.write(writer)?;
 720                         }
 721                 }
 722
 723                 if for_local_storage {
 724                         writer.write_all(&byte_utils::be64_to_array(self.remote_hash_commitment_number.len() as u64))?;
 725                         for (ref payment_hash, commitment_number) in self.remote_hash_commitment_number.iter() {
 726                                 writer.write_all(*payment_hash)?;
 727                                 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
 728                         }
 729                 } else {
 730                         writer.write_all(&byte_utils::be64_to_array(0))?;
 731                 }
 732
 733                 macro_rules! serialize_local_tx {
 734                         ($local_tx: expr) => {
 735                                 if let Err(e) = $local_tx.tx.consensus_encode(&mut WriterWriteAdaptor(writer)) {
 736                                         match e {
 737                                                 encode::Error::Io(e) => return Err(e),
 738                                                 _ => panic!("local tx must have been well-formed!"),
 739                                         }
 740                                 }
 741
 742                                 writer.write_all(&$local_tx.revocation_key.serialize())?;
 743                                 writer.write_all(&$local_tx.a_htlc_key.serialize())?;
 744                                 writer.write_all(&$local_tx.b_htlc_key.serialize())?;
 745                                 writer.write_all(&$local_tx.delayed_payment_key.serialize())?;
 746
 747                                 writer.write_all(&byte_utils::be64_to_array($local_tx.feerate_per_kw))?;
 748                                 writer.write_all(&byte_utils::be64_to_array($local_tx.htlc_outputs.len() as u64))?;
 749                                 for &(ref htlc_output, ref their_sig, ref our_sig) in $local_tx.htlc_outputs.iter() {
 750                                         serialize_htlc_in_commitment!(htlc_output);
 751                                         writer.write_all(&their_sig.serialize_compact(&self.secp_ctx))?;
 752                                         writer.write_all(&our_sig.serialize_compact(&self.secp_ctx))?;
 753                                 }
 754                         }
 755                 }
 756
 757                 if let Some(ref prev_local_tx) = self.prev_local_signed_commitment_tx {
 758                         writer.write_all(&[1; 1])?;
 759                         serialize_local_tx!(prev_local_tx);
 760                 } else {
 761                         writer.write_all(&[0; 1])?;
 762                 }
 763
 764                 if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
 765                         writer.write_all(&[1; 1])?;
 766                         serialize_local_tx!(cur_local_tx);
 767                 } else {
 768                         writer.write_all(&[0; 1])?;
 769                 }
 770
 771                 if for_local_storage {
 772                         writer.write_all(&byte_utils::be48_to_array(self.current_remote_commitment_number))?;
 773                 } else {
 774                         writer.write_all(&byte_utils::be48_to_array(0))?;
 775                 }
 776
 777                 writer.write_all(&byte_utils::be64_to_array(self.payment_preimages.len() as u64))?;
 778                 for payment_preimage in self.payment_preimages.values() {
 779                         writer.write_all(payment_preimage)?;
 780                 }
 781
 782                 self.last_block_hash.write(writer)?;
 783                 self.destination_script.write(writer)?;
 784
 785                 Ok(())
 786         }
 787
 788         /// Writes this monitor into the given writer, suitable for writing to disk.
 789         ///
 790         /// Note that the deserializer is only implemented for (Sha256dHash, ChannelMonitor), which
 791         /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
 792         /// the "reorg path" (ie not just starting at the same height but starting at the highest
 793         /// common block that appears on your best chain as well as on the chain which contains the
 794         /// last block hash returned) upon deserializing the object!
 795         pub fn write_for_disk<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
 796                 self.write(writer, true)
 797         }
 798
 799         /// Encodes this monitor into the given writer, suitable for sending to a remote watchtower
 800         ///
 801         /// Note that the deserializer is only implemented for (Sha256dHash, ChannelMonitor), which
 802         /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
 803         /// the "reorg path" (ie not just starting at the same height but starting at the highest
 804         /// common block that appears on your best chain as well as on the chain which contains the
 805         /// last block hash returned) upon deserializing the object!
 806         pub fn write_for_watchtower<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
 807                 self.write(writer, false)
 808         }
 809
 810         //TODO: Functions to serialize/deserialize (with different forms depending on which information
 811         //we want to leave out (eg funding_txo, etc).
 812
 813         /// Can only fail if idx is < get_min_seen_secret
 814         pub(super) fn get_secret(&self, idx: u64) -> Result<[u8; 32], HandleError> {
 815                 for i in 0..self.old_secrets.len() {
 816                         if (idx & (!((1 << i) - 1))) == self.old_secrets[i].1 {
 817                                 return Ok(ChannelMonitor::derive_secret(self.old_secrets[i].0, i as u8, idx))
 818                         }
 819                 }
 820                 assert!(idx < self.get_min_seen_secret());
 821                 Err(HandleError{err: "idx too low", action: None})
 822         }
 823
 824         pub(super) fn get_min_seen_secret(&self) -> u64 {
 825                 //TODO This can be optimized?
 826                 let mut min = 1 << 48;
 827                 for &(_, idx) in self.old_secrets.iter() {
 828                         if idx < min {
 829                                 min = idx;
 830                         }
 831                 }
 832                 min
 833         }
 834
 835         pub(super) fn get_cur_remote_commitment_number(&self) -> u64 {
 836                 self.current_remote_commitment_number
 837         }
 838
 839         pub(super) fn get_cur_local_commitment_number(&self) -> u64 {
 840                 if let &Some(ref local_tx) = &self.current_local_signed_commitment_tx {
 841                         0xffff_ffff_ffff - ((((local_tx.tx.input[0].sequence as u64 & 0xffffff) << 3*8) | (local_tx.tx.lock_time as u64 & 0xffffff)) ^ self.commitment_transaction_number_obscure_factor)
 842                 } else { 0xffff_ffff_ffff }
 843         }
 844
 845         /// Attempts to claim a remote commitment transaction's outputs using the revocation key and
 846         /// data in remote_claimable_outpoints. Will directly claim any HTLC outputs which expire at a
 847         /// height > height + CLTV_SHARED_CLAIM_BUFFER. In any case, will install monitoring for
 848         /// HTLC-Success/HTLC-Timeout transactions.
 849         fn check_spend_remote_transaction(&mut self, tx: &Transaction, height: u32) -> (Vec<Transaction>, (Sha256dHash, Vec<TxOut>), Vec<SpendableOutputDescriptor>) {
 850                 // Most secp and related errors trying to create keys means we have no hope of constructing
 851                 // a spend transaction...so we return no transactions to broadcast
 852                 let mut txn_to_broadcast = Vec::new();
 853                 let mut watch_outputs = Vec::new();
 854                 let mut spendable_outputs = Vec::new();
 855
 856                 let commitment_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
 857                 let per_commitment_option = self.remote_claimable_outpoints.get(&commitment_txid);
 858
 859                 macro_rules! ignore_error {
 860                         ( $thing : expr ) => {
 861                                 match $thing {
 862                                         Ok(a) => a,
 863                                         Err(_) => return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs)
 864                                 }
 865                         };
 866                 }
 867
 868                 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);
 869                 if commitment_number >= self.get_min_seen_secret() {
 870                         let secret = self.get_secret(commitment_number).unwrap();
 871                         let per_commitment_key = ignore_error!(SecretKey::from_slice(&self.secp_ctx, &secret));
 872                         let (revocation_pubkey, b_htlc_key) = match self.key_storage {
 873                                 KeyStorage::PrivMode { ref revocation_base_key, ref htlc_base_key, .. } => {
 874                                         let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
 875                                         (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &PublicKey::from_secret_key(&self.secp_ctx, &revocation_base_key))),
 876                                         ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &PublicKey::from_secret_key(&self.secp_ctx, &htlc_base_key))))
 877                                 },
 878                                 KeyStorage::SigsMode { ref revocation_base_key, ref htlc_base_key, .. } => {
 879                                         let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
 880                                         (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &revocation_base_key)),
 881                                         ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &htlc_base_key)))
 882                                 },
 883                         };
 884                         let delayed_key = ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key), &self.their_delayed_payment_base_key.unwrap()));
 885                         let a_htlc_key = match self.their_htlc_base_key {
 886                                 None => return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs),
 887                                 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)),
 888                         };
 889
 890                         let revokeable_redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.our_to_self_delay, &delayed_key);
 891                         let revokeable_p2wsh = revokeable_redeemscript.to_v0_p2wsh();
 892
 893                         let mut total_value = 0;
 894                         let mut values = Vec::new();
 895                         let mut inputs = Vec::new();
 896                         let mut htlc_idxs = Vec::new();
 897
 898                         for (idx, outp) in tx.output.iter().enumerate() {
 899                                 if outp.script_pubkey == revokeable_p2wsh {
 900                                         inputs.push(TxIn {
 901                                                 previous_output: BitcoinOutPoint {
 902                                                         txid: commitment_txid,
 903                                                         vout: idx as u32,
 904                                                 },
 905                                                 script_sig: Script::new(),
 906                                                 sequence: 0xfffffffd,
 907                                                 witness: Vec::new(),
 908                                         });
 909                                         htlc_idxs.push(None);
 910                                         values.push(outp.value);
 911                                         total_value += outp.value;
 912                                         break; // There can only be one of these
 913                                 }
 914                         }
 915
 916                         macro_rules! sign_input {
 917                                 ($sighash_parts: expr, $input: expr, $htlc_idx: expr, $amount: expr) => {
 918                                         {
 919                                                 let (sig, redeemscript) = match self.key_storage {
 920                                                         KeyStorage::PrivMode { ref revocation_base_key, .. } => {
 921                                                                 let redeemscript = if $htlc_idx.is_none() { revokeable_redeemscript.clone() } else {
 922                                                                         let htlc = &per_commitment_option.unwrap()[$htlc_idx.unwrap()];
 923                                                                         chan_utils::get_htlc_redeemscript_with_explicit_keys(htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey)
 924                                                                 };
 925                                                                 let sighash = ignore_error!(Message::from_slice(&$sighash_parts.sighash_all(&$input, &redeemscript, $amount)[..]));
 926                                                                 let revocation_key = ignore_error!(chan_utils::derive_private_revocation_key(&self.secp_ctx, &per_commitment_key, &revocation_base_key));
 927                                                                 (self.secp_ctx.sign(&sighash, &revocation_key), redeemscript)
 928                                                         },
 929                                                         KeyStorage::SigsMode { .. } => {
 930                                                                 unimplemented!();
 931                                                         }
 932                                                 };
 933                                                 $input.witness.push(sig.serialize_der(&self.secp_ctx).to_vec());
 934                                                 $input.witness[0].push(SigHashType::All as u8);
 935                                                 if $htlc_idx.is_none() {
 936                                                         $input.witness.push(vec!(1));
 937                                                 } else {
 938                                                         $input.witness.push(revocation_pubkey.serialize().to_vec());
 939                                                 }
 940                                                 $input.witness.push(redeemscript.into_bytes());
 941                                         }
 942                                 }
 943                         }
 944
 945                         if let Some(per_commitment_data) = per_commitment_option {
 946                                 inputs.reserve_exact(per_commitment_data.len());
 947
 948                                 for (idx, htlc) in per_commitment_data.iter().enumerate() {
 949                                         let expected_script = chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey);
 950                                         if htlc.transaction_output_index as usize >= tx.output.len() ||
 951                                                         tx.output[htlc.transaction_output_index as usize].value != htlc.amount_msat / 1000 ||
 952                                                         tx.output[htlc.transaction_output_index as usize].script_pubkey != expected_script.to_v0_p2wsh() {
 953                                                 return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs); // Corrupted per_commitment_data, fuck this user
 954                                         }
 955                                         let input = TxIn {
 956                                                 previous_output: BitcoinOutPoint {
 957                                                         txid: commitment_txid,
 958                                                         vout: htlc.transaction_output_index,
 959                                                 },
 960                                                 script_sig: Script::new(),
 961                                                 sequence: 0xfffffffd,
 962                                                 witness: Vec::new(),
 963                                         };
 964                                         if htlc.cltv_expiry > height + CLTV_SHARED_CLAIM_BUFFER {
 965                                                 inputs.push(input);
 966                                                 htlc_idxs.push(Some(idx));
 967                                                 values.push(tx.output[htlc.transaction_output_index as usize].value);
 968                                                 total_value += htlc.amount_msat / 1000;
 969                                         } else {
 970                                                 let mut single_htlc_tx = Transaction {
 971                                                         version: 2,
 972                                                         lock_time: 0,
 973                                                         input: vec![input],
 974                                                         output: vec!(TxOut {
 975                                                                 script_pubkey: self.destination_script.clone(),
 976                                                                 value: htlc.amount_msat / 1000, //TODO: - fee
 977                                                         }),
 978                                                 };
 979                                                 let sighash_parts = bip143::SighashComponents::new(&single_htlc_tx);
 980                                                 sign_input!(sighash_parts, single_htlc_tx.input[0], Some(idx), htlc.amount_msat / 1000);
 981                                                 txn_to_broadcast.push(single_htlc_tx);
 982                                         }
 983                                 }
 984                         }
 985
 986                         if !inputs.is_empty() || !txn_to_broadcast.is_empty() { // ie we're confident this is actually ours
 987                                 // We're definitely a remote commitment transaction!
 988                                 watch_outputs.append(&mut tx.output.clone());
 989                                 self.remote_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
 990                         }
 991                         if inputs.is_empty() { return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs); } // Nothing to be done...probably a false positive/local tx
 992
 993                         let outputs = vec!(TxOut {
 994                                 script_pubkey: self.destination_script.clone(),
 995                                 value: total_value, //TODO: - fee
 996                         });
 997                         let mut spend_tx = Transaction {
 998                                 version: 2,
 999                                 lock_time: 0,
1000                                 input: inputs,
1001                                 output: outputs,
1002                         };
1003
1004                         let mut values_drain = values.drain(..);
1005                         let sighash_parts = bip143::SighashComponents::new(&spend_tx);
1006
1007                         for (input, htlc_idx) in spend_tx.input.iter_mut().zip(htlc_idxs.iter()) {
1008                                 let value = values_drain.next().unwrap();
1009                                 sign_input!(sighash_parts, input, htlc_idx, value);
1010                         }
1011
1012                         spendable_outputs.push(SpendableOutputDescriptor::StaticOutput {
1013                                 outpoint: BitcoinOutPoint { txid: spend_tx.txid(), vout: 0 },
1014                                 output: spend_tx.output[0].clone(),
1015                         });
1016                         txn_to_broadcast.push(spend_tx);
1017                 } else if let Some(per_commitment_data) = per_commitment_option {
1018                         // While this isn't useful yet, there is a potential race where if a counterparty
1019                         // revokes a state at the same time as the commitment transaction for that state is
1020                         // confirmed, and the watchtower receives the block before the user, the user could
1021                         // upload a new ChannelMonitor with the revocation secret but the watchtower has
1022                         // already processed the block, resulting in the remote_commitment_txn_on_chain entry
1023                         // not being generated by the above conditional. Thus, to be safe, we go ahead and
1024                         // insert it here.
1025                         watch_outputs.append(&mut tx.output.clone());
1026                         self.remote_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
1027
1028                         if let Some(revocation_points) = self.their_cur_revocation_points {
1029                                 let revocation_point_option =
1030                                         if revocation_points.0 == commitment_number { Some(&revocation_points.1) }
1031                                         else if let Some(point) = revocation_points.2.as_ref() {
1032                                                 if revocation_points.0 == commitment_number + 1 { Some(point) } else { None }
1033                                         } else { None };
1034                                 if let Some(revocation_point) = revocation_point_option {
1035                                         let (revocation_pubkey, b_htlc_key) = match self.key_storage {
1036                                                 KeyStorage::PrivMode { ref revocation_base_key, ref htlc_base_key, .. } => {
1037                                                         (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, revocation_point, &PublicKey::from_secret_key(&self.secp_ctx, &revocation_base_key))),
1038                                                         ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &PublicKey::from_secret_key(&self.secp_ctx, &htlc_base_key))))
1039                                                 },
1040                                                 KeyStorage::SigsMode { ref revocation_base_key, ref htlc_base_key, .. } => {
1041                                                         (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, revocation_point, &revocation_base_key)),
1042                                                         ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &htlc_base_key)))
1043                                                 },
1044                                         };
1045                                         let a_htlc_key = match self.their_htlc_base_key {
1046                                                 None => return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs),
1047                                                 Some(their_htlc_base_key) => ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &their_htlc_base_key)),
1048                                         };
1049
1050                                         let mut total_value = 0;
1051                                         let mut values = Vec::new();
1052                                         let mut inputs = Vec::new();
1053
1054                                         macro_rules! sign_input {
1055                                                 ($sighash_parts: expr, $input: expr, $amount: expr, $preimage: expr) => {
1056                                                         {
1057                                                                 let (sig, redeemscript) = match self.key_storage {
1058                                                                         KeyStorage::PrivMode { ref htlc_base_key, .. } => {
1059                                                                                 let htlc = &per_commitment_option.unwrap()[$input.sequence as usize];
1060                                                                                 let redeemscript = chan_utils::get_htlc_redeemscript_with_explicit_keys(htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey);
1061                                                                                 let sighash = ignore_error!(Message::from_slice(&$sighash_parts.sighash_all(&$input, &redeemscript, $amount)[..]));
1062                                                                                 let htlc_key = ignore_error!(chan_utils::derive_private_key(&self.secp_ctx, revocation_point, &htlc_base_key));
1063                                                                                 (self.secp_ctx.sign(&sighash, &htlc_key), redeemscript)
1064                                                                         },
1065                                                                         KeyStorage::SigsMode { .. } => {
1066                                                                                 unimplemented!();
1067                                                                         }
1068                                                                 };
1069                                                                 $input.witness.push(sig.serialize_der(&self.secp_ctx).to_vec());
1070                                                                 $input.witness[0].push(SigHashType::All as u8);
1071                                                                 $input.witness.push($preimage);
1072                                                                 $input.witness.push(redeemscript.into_bytes());
1073                                                         }
1074                                                 }
1075                                         }
1076
1077                                         for (idx, htlc) in per_commitment_data.iter().enumerate() {
1078                                                 if let Some(payment_preimage) = self.payment_preimages.get(&htlc.payment_hash) {
1079                                                         let input = TxIn {
1080                                                                 previous_output: BitcoinOutPoint {
1081                                                                         txid: commitment_txid,
1082                                                                         vout: htlc.transaction_output_index,
1083                                                                 },
1084                                                                 script_sig: Script::new(),
1085                                                                 sequence: idx as u32, // reset to 0xfffffffd in sign_input
1086                                                                 witness: Vec::new(),
1087                                                         };
1088                                                         if htlc.cltv_expiry > height + CLTV_SHARED_CLAIM_BUFFER {
1089                                                                 inputs.push(input);
1090                                                                 values.push((tx.output[htlc.transaction_output_index as usize].value, payment_preimage));
1091                                                                 total_value += htlc.amount_msat / 1000;
1092                                                         } else {
1093                                                                 let mut single_htlc_tx = Transaction {
1094                                                                         version: 2,
1095                                                                         lock_time: 0,
1096                                                                         input: vec![input],
1097                                                                         output: vec!(TxOut {
1098                                                                                 script_pubkey: self.destination_script.clone(),
1099                                                                                 value: htlc.amount_msat / 1000, //TODO: - fee
1100                                                                         }),
1101                                                                 };
1102                                                                 let sighash_parts = bip143::SighashComponents::new(&single_htlc_tx);
1103                                                                 sign_input!(sighash_parts, single_htlc_tx.input[0], htlc.amount_msat / 1000, payment_preimage.to_vec());
1104                                                                 spendable_outputs.push(SpendableOutputDescriptor::StaticOutput {
1105                                                                         outpoint: BitcoinOutPoint { txid: single_htlc_tx.txid(), vout: 0 },
1106                                                                         output: single_htlc_tx.output[0].clone(),
1107                                                                 });
1108                                                                 txn_to_broadcast.push(single_htlc_tx);
1109                                                         }
1110                                                 }
1111                                         }
1112
1113                                         if inputs.is_empty() { return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs); } // Nothing to be done...probably a false positive/local tx
1114
1115                                         let outputs = vec!(TxOut {
1116                                                 script_pubkey: self.destination_script.clone(),
1117                                                 value: total_value, //TODO: - fee
1118                                         });
1119                                         let mut spend_tx = Transaction {
1120                                                 version: 2,
1121                                                 lock_time: 0,
1122                                                 input: inputs,
1123                                                 output: outputs,
1124                                         };
1125
1126                                         let mut values_drain = values.drain(..);
1127                                         let sighash_parts = bip143::SighashComponents::new(&spend_tx);
1128
1129                                         for input in spend_tx.input.iter_mut() {
1130                                                 let value = values_drain.next().unwrap();
1131                                                 sign_input!(sighash_parts, input, value.0, value.1.to_vec());
1132                                         }
1133
1134                                         spendable_outputs.push(SpendableOutputDescriptor::StaticOutput {
1135                                                 outpoint: BitcoinOutPoint { txid: spend_tx.txid(), vout: 0 },
1136                                                 output: spend_tx.output[0].clone(),
1137                                         });
1138                                         txn_to_broadcast.push(spend_tx);
1139                                 }
1140                         }
1141                 }
1142
1143                 (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs)
1144         }
1145
1146         /// Attempst to claim a remote HTLC-Success/HTLC-Timeout s outputs using the revocation key
1147         fn check_spend_remote_htlc(&self, tx: &Transaction, commitment_number: u64) -> (Option<Transaction>, Option<SpendableOutputDescriptor>) {
1148                 if tx.input.len() != 1 || tx.output.len() != 1 {
1149                         return (None, None)
1150                 }
1151
1152                 macro_rules! ignore_error {
1153                         ( $thing : expr ) => {
1154                                 match $thing {
1155                                         Ok(a) => a,
1156                                         Err(_) => return (None, None)
1157                                 }
1158                         };
1159                 }
1160
1161                 let secret = ignore_error!(self.get_secret(commitment_number));
1162                 let per_commitment_key = ignore_error!(SecretKey::from_slice(&self.secp_ctx, &secret));
1163                 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1164                 let revocation_pubkey = match self.key_storage {
1165                         KeyStorage::PrivMode { ref revocation_base_key, .. } => {
1166                                 ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &PublicKey::from_secret_key(&self.secp_ctx, &revocation_base_key)))
1167                         },
1168                         KeyStorage::SigsMode { ref revocation_base_key, .. } => {
1169                                 ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &revocation_base_key))
1170                         },
1171                 };
1172                 let delayed_key = match self.their_delayed_payment_base_key {
1173                         None => return (None, None),
1174                         Some(their_delayed_payment_base_key) => ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &their_delayed_payment_base_key)),
1175                 };
1176                 let redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.their_to_self_delay.unwrap(), &delayed_key);
1177                 let revokeable_p2wsh = redeemscript.to_v0_p2wsh();
1178                 let htlc_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
1179
1180                 let mut inputs = Vec::new();
1181                 let mut amount = 0;
1182
1183                 if tx.output[0].script_pubkey == revokeable_p2wsh { //HTLC transactions have one txin, one txout
1184                         inputs.push(TxIn {
1185                                 previous_output: BitcoinOutPoint {
1186                                         txid: htlc_txid,
1187                                         vout: 0,
1188                                 },
1189                                 script_sig: Script::new(),
1190                                 sequence: 0xfffffffd,
1191                                 witness: Vec::new(),
1192                         });
1193                         amount = tx.output[0].value;
1194                 }
1195
1196                 if !inputs.is_empty() {
1197                         let outputs = vec!(TxOut {
1198                                 script_pubkey: self.destination_script.clone(),
1199                                 value: amount, //TODO: - fee
1200                         });
1201
1202                         let mut spend_tx = Transaction {
1203                                 version: 2,
1204                                 lock_time: 0,
1205                                 input: inputs,
1206                                 output: outputs,
1207                         };
1208
1209                         let sighash_parts = bip143::SighashComponents::new(&spend_tx);
1210
1211                         let sig = match self.key_storage {
1212                                 KeyStorage::PrivMode { ref revocation_base_key, .. } => {
1213                                         let sighash = ignore_error!(Message::from_slice(&sighash_parts.sighash_all(&spend_tx.input[0], &redeemscript, amount)[..]));
1214                                         let revocation_key = ignore_error!(chan_utils::derive_private_revocation_key(&self.secp_ctx, &per_commitment_key, &revocation_base_key));
1215                                         self.secp_ctx.sign(&sighash, &revocation_key)
1216                                 }
1217                                 KeyStorage::SigsMode { .. } => {
1218                                         unimplemented!();
1219                                 }
1220                         };
1221                         spend_tx.input[0].witness.push(sig.serialize_der(&self.secp_ctx).to_vec());
1222                         spend_tx.input[0].witness[0].push(SigHashType::All as u8);
1223                         spend_tx.input[0].witness.push(vec!(1));
1224                         spend_tx.input[0].witness.push(redeemscript.into_bytes());
1225
1226                         let outpoint = BitcoinOutPoint { txid: spend_tx.txid(), vout: 0 };
1227                         let output = spend_tx.output[0].clone();
1228                         (Some(spend_tx), Some(SpendableOutputDescriptor::StaticOutput { outpoint, output }))
1229                 } else { (None, None) }
1230         }
1231
1232         fn broadcast_by_local_state(&self, local_tx: &LocalSignedTx, per_commitment_point: &Option<PublicKey>, delayed_payment_base_key: &Option<SecretKey>) -> (Vec<Transaction>, Vec<SpendableOutputDescriptor>) {
1233                 let mut res = Vec::with_capacity(local_tx.htlc_outputs.len());
1234                 let mut spendable_outputs = Vec::with_capacity(local_tx.htlc_outputs.len());
1235
1236                 macro_rules! add_dynamic_output {
1237                         ($father_tx: expr, $vout: expr) => {
1238                                 if let Some(ref per_commitment_point) = *per_commitment_point {
1239                                         if let Some(ref delayed_payment_base_key) = *delayed_payment_base_key {
1240                                                 if let Ok(local_delayedkey) = chan_utils::derive_private_key(&self.secp_ctx, per_commitment_point, delayed_payment_base_key) {
1241                                                         spendable_outputs.push(SpendableOutputDescriptor::DynamicOutput {
1242                                                                 outpoint: BitcoinOutPoint { txid: $father_tx.txid(), vout: $vout },
1243                                                                 local_delayedkey,
1244                                                                 witness_script: chan_utils::get_revokeable_redeemscript(&local_tx.revocation_key, self.our_to_self_delay, &local_tx.delayed_payment_key),
1245                                                                 to_self_delay: self.our_to_self_delay,
1246                                                                 output: $father_tx.output[$vout as usize].clone(),
1247                                                         });
1248                                                 }
1249                                         }
1250                                 }
1251                         }
1252                 }
1253
1254
1255                 let redeemscript = chan_utils::get_revokeable_redeemscript(&local_tx.revocation_key, self.their_to_self_delay.unwrap(), &local_tx.delayed_payment_key);
1256                 let revokeable_p2wsh = redeemscript.to_v0_p2wsh();
1257                 for (idx, output) in local_tx.tx.output.iter().enumerate() {
1258                         if output.script_pubkey == revokeable_p2wsh {
1259                                 add_dynamic_output!(local_tx.tx, idx as u32);
1260                                 break;
1261                         }
1262                 }
1263
1264                 for &(ref htlc, ref their_sig, ref our_sig) in local_tx.htlc_outputs.iter() {
1265                         if htlc.offered {
1266                                 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);
1267
1268                                 htlc_timeout_tx.input[0].witness.push(Vec::new()); // First is the multisig dummy
1269
1270                                 htlc_timeout_tx.input[0].witness.push(their_sig.serialize_der(&self.secp_ctx).to_vec());
1271                                 htlc_timeout_tx.input[0].witness[1].push(SigHashType::All as u8);
1272                                 htlc_timeout_tx.input[0].witness.push(our_sig.serialize_der(&self.secp_ctx).to_vec());
1273                                 htlc_timeout_tx.input[0].witness[2].push(SigHashType::All as u8);
1274
1275                                 htlc_timeout_tx.input[0].witness.push(Vec::new());
1276                                 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());
1277
1278                                 add_dynamic_output!(htlc_timeout_tx, 0);
1279                                 res.push(htlc_timeout_tx);
1280                         } else {
1281                                 if let Some(payment_preimage) = self.payment_preimages.get(&htlc.payment_hash) {
1282                                         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);
1283
1284                                         htlc_success_tx.input[0].witness.push(Vec::new()); // First is the multisig dummy
1285
1286                                         htlc_success_tx.input[0].witness.push(their_sig.serialize_der(&self.secp_ctx).to_vec());
1287                                         htlc_success_tx.input[0].witness[1].push(SigHashType::All as u8);
1288                                         htlc_success_tx.input[0].witness.push(our_sig.serialize_der(&self.secp_ctx).to_vec());
1289                                         htlc_success_tx.input[0].witness[2].push(SigHashType::All as u8);
1290
1291                                         htlc_success_tx.input[0].witness.push(payment_preimage.to_vec());
1292                                         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());
1293
1294                                         add_dynamic_output!(htlc_success_tx, 0);
1295                                         res.push(htlc_success_tx);
1296                                 }
1297                         }
1298                 }
1299
1300                 (res, spendable_outputs)
1301         }
1302
1303         /// Attempts to claim any claimable HTLCs in a commitment transaction which was not (yet)
1304         /// revoked using data in local_claimable_outpoints.
1305         /// Should not be used if check_spend_revoked_transaction succeeds.
1306         fn check_spend_local_transaction(&self, tx: &Transaction, _height: u32) -> (Vec<Transaction>, Vec<SpendableOutputDescriptor>) {
1307                 let commitment_txid = tx.txid();
1308                 if let &Some(ref local_tx) = &self.current_local_signed_commitment_tx {
1309                         if local_tx.txid == commitment_txid {
1310                                 match self.key_storage {
1311                                         KeyStorage::PrivMode { revocation_base_key: _, htlc_base_key: _, ref delayed_payment_base_key, prev_latest_per_commitment_point: _, ref latest_per_commitment_point } => {
1312                                                 return self.broadcast_by_local_state(local_tx, latest_per_commitment_point, &Some(*delayed_payment_base_key));
1313                                         },
1314                                         KeyStorage::SigsMode { .. } => {
1315                                                 return self.broadcast_by_local_state(local_tx, &None, &None);
1316                                         }
1317                                 }
1318                         }
1319                 }
1320                 if let &Some(ref local_tx) = &self.prev_local_signed_commitment_tx {
1321                         if local_tx.txid == commitment_txid {
1322                                 match self.key_storage {
1323                                         KeyStorage::PrivMode { revocation_base_key: _, htlc_base_key: _, ref delayed_payment_base_key, ref prev_latest_per_commitment_point, .. } => {
1324                                                 return self.broadcast_by_local_state(local_tx, prev_latest_per_commitment_point, &Some(*delayed_payment_base_key));
1325                                         },
1326                                         KeyStorage::SigsMode { .. } => {
1327                                                 return self.broadcast_by_local_state(local_tx, &None, &None);
1328                                         }
1329                                 }
1330                         }
1331                 }
1332                 (Vec::new(), Vec::new())
1333         }
1334
1335         /// Used by ChannelManager deserialization to broadcast the latest local state if it's copy of
1336         /// the Channel was out-of-date.
1337         pub(super) fn get_latest_local_commitment_txn(&self) -> Vec<Transaction> {
1338                 if let &Some(ref local_tx) = &self.current_local_signed_commitment_tx {
1339                         let mut res = vec![local_tx.tx.clone()];
1340                         match self.key_storage {
1341                                 KeyStorage::PrivMode { ref delayed_payment_base_key, ref prev_latest_per_commitment_point, .. } => {
1342                                         res.append(&mut self.broadcast_by_local_state(local_tx, prev_latest_per_commitment_point, &Some(*delayed_payment_base_key)).0);
1343                                 },
1344                                 _ => panic!("Can only broadcast by local channelmonitor"),
1345                         };
1346                         res
1347                 } else {
1348                         Vec::new()
1349                 }
1350         }
1351
1352         fn block_connected(&mut self, txn_matched: &[&Transaction], height: u32, block_hash: &Sha256dHash, broadcaster: &BroadcasterInterface)-> (Vec<(Sha256dHash, Vec<TxOut>)>, Vec<SpendableOutputDescriptor>) {
1353                 let mut watch_outputs = Vec::new();
1354                 let mut spendable_outputs = Vec::new();
1355                 for tx in txn_matched {
1356                         if tx.input.len() == 1 {
1357                                 // Assuming our keys were not leaked (in which case we're screwed no matter what),
1358                                 // commitment transactions and HTLC transactions will all only ever have one input,
1359                                 // which is an easy way to filter out any potential non-matching txn for lazy
1360                                 // filters.
1361                                 let prevout = &tx.input[0].previous_output;
1362                                 let mut txn: Vec<Transaction> = Vec::new();
1363                                 if self.funding_txo.is_none() || (prevout.txid == self.funding_txo.as_ref().unwrap().0.txid && prevout.vout == self.funding_txo.as_ref().unwrap().0.index as u32) {
1364                                         let (remote_txn, new_outputs, mut spendable_output) = self.check_spend_remote_transaction(tx, height);
1365                                         txn = remote_txn;
1366                                         spendable_outputs.append(&mut spendable_output);
1367                                         if !new_outputs.1.is_empty() {
1368                                                 watch_outputs.push(new_outputs);
1369                                         }
1370                                         if txn.is_empty() {
1371                                                 let (remote_txn, mut outputs) = self.check_spend_local_transaction(tx, height);
1372                                                 spendable_outputs.append(&mut outputs);
1373                                                 txn = remote_txn;
1374                                         }
1375                                 } else {
1376                                         if let Some(&(commitment_number, _)) = self.remote_commitment_txn_on_chain.get(&prevout.txid) {
1377                                                 let (tx, spendable_output) = self.check_spend_remote_htlc(tx, commitment_number);
1378                                                 if let Some(tx) = tx {
1379                                                         txn.push(tx);
1380                                                 }
1381                                                 if let Some(spendable_output) = spendable_output {
1382                                                         spendable_outputs.push(spendable_output);
1383                                                 }
1384                                         }
1385                                 }
1386                                 for tx in txn.iter() {
1387                                         broadcaster.broadcast_transaction(tx);
1388                                 }
1389                         }
1390                 }
1391                 if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
1392                         if self.would_broadcast_at_height(height) {
1393                                 broadcaster.broadcast_transaction(&cur_local_tx.tx);
1394                                 match self.key_storage {
1395                                         KeyStorage::PrivMode { revocation_base_key: _, htlc_base_key: _, ref delayed_payment_base_key, prev_latest_per_commitment_point: _, ref latest_per_commitment_point } => {
1396                                                 let (txs, mut outputs) = self.broadcast_by_local_state(&cur_local_tx, latest_per_commitment_point, &Some(*delayed_payment_base_key));
1397                                                 spendable_outputs.append(&mut outputs);
1398                                                 for tx in txs {
1399                                                         broadcaster.broadcast_transaction(&tx);
1400                                                 }
1401                                         },
1402                                         KeyStorage::SigsMode { .. } => {
1403                                                 let (txs, mut outputs) = self.broadcast_by_local_state(&cur_local_tx, &None, &None);
1404                                                 spendable_outputs.append(&mut outputs);
1405                                                 for tx in txs {
1406                                                         broadcaster.broadcast_transaction(&tx);
1407                                                 }
1408                                         }
1409                                 }
1410                         }
1411                 }
1412                 self.last_block_hash = block_hash.clone();
1413                 (watch_outputs, spendable_outputs)
1414         }
1415
1416         pub(super) fn would_broadcast_at_height(&self, height: u32) -> bool {
1417                 if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
1418                         for &(ref htlc, _, _) in cur_local_tx.htlc_outputs.iter() {
1419                                 // For inbound HTLCs which we know the preimage for, we have to ensure we hit the
1420                                 // chain with enough room to claim the HTLC without our counterparty being able to
1421                                 // time out the HTLC first.
1422                                 // For outbound HTLCs which our counterparty hasn't failed/claimed, our primary
1423                                 // concern is being able to claim the corresponding inbound HTLC (on another
1424                                 // channel) before it expires. In fact, we don't even really care if our
1425                                 // counterparty here claims such an outbound HTLC after it expired as long as we
1426                                 // can still claim the corresponding HTLC. Thus, to avoid needlessly hitting the
1427                                 // chain when our counterparty is waiting for expiration to off-chain fail an HTLC
1428                                 // we give ourselves a few blocks of headroom after expiration before going
1429                                 // on-chain for an expired HTLC.
1430                                 // Note that, to avoid a potential attack whereby a node delays claiming an HTLC
1431                                 // from us until we've reached the point where we go on-chain with the
1432                                 // corresponding inbound HTLC, we must ensure that outbound HTLCs go on chain at
1433                                 // least CLTV_CLAIM_BUFFER blocks prior to the inbound HTLC.
1434                                 //  aka outbound_cltv + HTLC_FAIL_TIMEOUT_BLOCKS == height - CLTV_CLAIM_BUFFER
1435                                 //      inbound_cltv == height + CLTV_CLAIM_BUFFER
1436                                 //      outbound_cltv + HTLC_FAIL_TIMEOUT_BLOCKS + CLTV_CLAIM_BUFER <= inbound_cltv - CLTV_CLAIM_BUFFER
1437                                 //      HTLC_FAIL_TIMEOUT_BLOCKS + 2*CLTV_CLAIM_BUFER <= inbound_cltv - outbound_cltv
1438                                 //      HTLC_FAIL_TIMEOUT_BLOCKS + 2*CLTV_CLAIM_BUFER <= CLTV_EXPIRY_DELTA
1439                                 if ( htlc.offered && htlc.cltv_expiry + HTLC_FAIL_TIMEOUT_BLOCKS <= height) ||
1440                                    (!htlc.offered && htlc.cltv_expiry <= height + CLTV_CLAIM_BUFFER && self.payment_preimages.contains_key(&htlc.payment_hash)) {
1441                                         return true;
1442                                 }
1443                         }
1444                 }
1445                 false
1446         }
1447 }
1448
1449 const MAX_ALLOC_SIZE: usize = 64*1024;
1450
1451 impl<R: ::std::io::Read> ReadableArgs<R, Arc<Logger>> for (Sha256dHash, ChannelMonitor) {
1452         fn read(reader: &mut R, logger: Arc<Logger>) -> Result<Self, DecodeError> {
1453                 let secp_ctx = Secp256k1::new();
1454                 macro_rules! unwrap_obj {
1455                         ($key: expr) => {
1456                                 match $key {
1457                                         Ok(res) => res,
1458                                         Err(_) => return Err(DecodeError::InvalidValue),
1459                                 }
1460                         }
1461                 }
1462
1463                 let _ver: u8 = Readable::read(reader)?;
1464                 let min_ver: u8 = Readable::read(reader)?;
1465                 if min_ver > SERIALIZATION_VERSION {
1466                         return Err(DecodeError::UnknownVersion);
1467                 }
1468
1469                 // Technically this can fail and serialize fail a round-trip, but only for serialization of
1470                 // barely-init'd ChannelMonitors that we can't do anything with.
1471                 let outpoint = OutPoint {
1472                         txid: Readable::read(reader)?,
1473                         index: Readable::read(reader)?,
1474                 };
1475                 let funding_txo = Some((outpoint, Readable::read(reader)?));
1476                 let commitment_transaction_number_obscure_factor = <U48 as Readable<R>>::read(reader)?.0;
1477
1478                 let key_storage = match <u8 as Readable<R>>::read(reader)? {
1479                         0 => {
1480                                 let revocation_base_key = Readable::read(reader)?;
1481                                 let htlc_base_key = Readable::read(reader)?;
1482                                 let delayed_payment_base_key = Readable::read(reader)?;
1483                                 let prev_latest_per_commitment_point = match <u8 as Readable<R>>::read(reader)? {
1484                                         0 => None,
1485                                         1 => Some(Readable::read(reader)?),
1486                                         _ => return Err(DecodeError::InvalidValue),
1487                                 };
1488                                 let latest_per_commitment_point = match <u8 as Readable<R>>::read(reader)? {
1489                                         0 => None,
1490                                         1 => Some(Readable::read(reader)?),
1491                                         _ => return Err(DecodeError::InvalidValue),
1492                                 };
1493                                 KeyStorage::PrivMode {
1494                                         revocation_base_key,
1495                                         htlc_base_key,
1496                                         delayed_payment_base_key,
1497                                         prev_latest_per_commitment_point,
1498                                         latest_per_commitment_point,
1499                                 }
1500                         },
1501                         _ => return Err(DecodeError::InvalidValue),
1502                 };
1503
1504                 let their_htlc_base_key = Some(Readable::read(reader)?);
1505                 let their_delayed_payment_base_key = Some(Readable::read(reader)?);
1506
1507                 let their_cur_revocation_points = {
1508                         let first_idx = <U48 as Readable<R>>::read(reader)?.0;
1509                         if first_idx == 0 {
1510                                 None
1511                         } else {
1512                                 let first_point = Readable::read(reader)?;
1513                                 let second_point_slice: [u8; 33] = Readable::read(reader)?;
1514                                 if second_point_slice[0..32] == [0; 32] && second_point_slice[32] == 0 {
1515                                         Some((first_idx, first_point, None))
1516                                 } else {
1517                                         Some((first_idx, first_point, Some(unwrap_obj!(PublicKey::from_slice(&secp_ctx, &second_point_slice)))))
1518                                 }
1519                         }
1520                 };
1521
1522                 let our_to_self_delay: u16 = Readable::read(reader)?;
1523                 let their_to_self_delay: Option<u16> = Some(Readable::read(reader)?);
1524
1525                 let mut old_secrets = [([0; 32], 1 << 48); 49];
1526                 for &mut (ref mut secret, ref mut idx) in old_secrets.iter_mut() {
1527                         *secret = Readable::read(reader)?;
1528                         *idx = Readable::read(reader)?;
1529                 }
1530
1531                 macro_rules! read_htlc_in_commitment {
1532                         () => {
1533                                 {
1534                                         let offered: bool = Readable::read(reader)?;
1535                                         let amount_msat: u64 = Readable::read(reader)?;
1536                                         let cltv_expiry: u32 = Readable::read(reader)?;
1537                                         let payment_hash: [u8; 32] = Readable::read(reader)?;
1538                                         let transaction_output_index: u32 = Readable::read(reader)?;
1539
1540                                         HTLCOutputInCommitment {
1541                                                 offered, amount_msat, cltv_expiry, payment_hash, transaction_output_index
1542                                         }
1543                                 }
1544                         }
1545                 }
1546
1547                 let remote_claimable_outpoints_len: u64 = Readable::read(reader)?;
1548                 let mut remote_claimable_outpoints = HashMap::with_capacity(cmp::min(remote_claimable_outpoints_len as usize, MAX_ALLOC_SIZE / 64));
1549                 for _ in 0..remote_claimable_outpoints_len {
1550                         let txid: Sha256dHash = Readable::read(reader)?;
1551                         let outputs_count: u64 = Readable::read(reader)?;
1552                         let mut outputs = Vec::with_capacity(cmp::min(outputs_count as usize, MAX_ALLOC_SIZE / 32));
1553                         for _ in 0..outputs_count {
1554                                 outputs.push(read_htlc_in_commitment!());
1555                         }
1556                         if let Some(_) = remote_claimable_outpoints.insert(txid, outputs) {
1557                                 return Err(DecodeError::InvalidValue);
1558                         }
1559                 }
1560
1561                 let remote_commitment_txn_on_chain_len: u64 = Readable::read(reader)?;
1562                 let mut remote_commitment_txn_on_chain = HashMap::with_capacity(cmp::min(remote_commitment_txn_on_chain_len as usize, MAX_ALLOC_SIZE / 32));
1563                 for _ in 0..remote_commitment_txn_on_chain_len {
1564                         let txid: Sha256dHash = Readable::read(reader)?;
1565                         let commitment_number = <U48 as Readable<R>>::read(reader)?.0;
1566                         let outputs_count = <u64 as Readable<R>>::read(reader)?;
1567                         let mut outputs = Vec::with_capacity(cmp::min(outputs_count as usize, MAX_ALLOC_SIZE / 8));
1568                         for _ in 0..outputs_count {
1569                                 outputs.push(Readable::read(reader)?);
1570                         }
1571                         if let Some(_) = remote_commitment_txn_on_chain.insert(txid, (commitment_number, outputs)) {
1572                                 return Err(DecodeError::InvalidValue);
1573                         }
1574                 }
1575
1576                 let remote_hash_commitment_number_len: u64 = Readable::read(reader)?;
1577                 let mut remote_hash_commitment_number = HashMap::with_capacity(cmp::min(remote_hash_commitment_number_len as usize, MAX_ALLOC_SIZE / 32));
1578                 for _ in 0..remote_hash_commitment_number_len {
1579                         let txid: [u8; 32] = Readable::read(reader)?;
1580                         let commitment_number = <U48 as Readable<R>>::read(reader)?.0;
1581                         if let Some(_) = remote_hash_commitment_number.insert(txid, commitment_number) {
1582                                 return Err(DecodeError::InvalidValue);
1583                         }
1584                 }
1585
1586                 macro_rules! read_local_tx {
1587                         () => {
1588                                 {
1589                                         let tx = match Transaction::consensus_decode(reader.by_ref()) {
1590                                                 Ok(tx) => tx,
1591                                                 Err(e) => match e {
1592                                                         encode::Error::Io(ioe) => return Err(DecodeError::Io(ioe)),
1593                                                         _ => return Err(DecodeError::InvalidValue),
1594                                                 },
1595                                         };
1596
1597                                         if tx.input.is_empty() {
1598                                                 // Ensure tx didn't hit the 0-input ambiguity case.
1599                                                 return Err(DecodeError::InvalidValue);
1600                                         }
1601
1602                                         let revocation_key = Readable::read(reader)?;
1603                                         let a_htlc_key = Readable::read(reader)?;
1604                                         let b_htlc_key = Readable::read(reader)?;
1605                                         let delayed_payment_key = Readable::read(reader)?;
1606                                         let feerate_per_kw: u64 = Readable::read(reader)?;
1607
1608                                         let htlc_outputs_len: u64 = Readable::read(reader)?;
1609                                         let mut htlc_outputs = Vec::with_capacity(cmp::min(htlc_outputs_len as usize, MAX_ALLOC_SIZE / 128));
1610                                         for _ in 0..htlc_outputs_len {
1611                                                 htlc_outputs.push((read_htlc_in_commitment!(), Readable::read(reader)?, Readable::read(reader)?));
1612                                         }
1613
1614                                         LocalSignedTx {
1615                                                 txid: tx.txid(),
1616                                                 tx, revocation_key, a_htlc_key, b_htlc_key, delayed_payment_key, feerate_per_kw, htlc_outputs
1617                                         }
1618                                 }
1619                         }
1620                 }
1621
1622                 let prev_local_signed_commitment_tx = match <u8 as Readable<R>>::read(reader)? {
1623                         0 => None,
1624                         1 => {
1625                                 Some(read_local_tx!())
1626                         },
1627                         _ => return Err(DecodeError::InvalidValue),
1628                 };
1629
1630                 let current_local_signed_commitment_tx = match <u8 as Readable<R>>::read(reader)? {
1631                         0 => None,
1632                         1 => {
1633                                 Some(read_local_tx!())
1634                         },
1635                         _ => return Err(DecodeError::InvalidValue),
1636                 };
1637
1638                 let current_remote_commitment_number = <U48 as Readable<R>>::read(reader)?.0;
1639
1640                 let payment_preimages_len: u64 = Readable::read(reader)?;
1641                 let mut payment_preimages = HashMap::with_capacity(cmp::min(payment_preimages_len as usize, MAX_ALLOC_SIZE / 32));
1642                 let mut sha = Sha256::new();
1643                 for _ in 0..payment_preimages_len {
1644                         let preimage: [u8; 32] = Readable::read(reader)?;
1645                         sha.reset();
1646                         sha.input(&preimage);
1647                         let mut hash = [0; 32];
1648                         sha.result(&mut hash);
1649                         if let Some(_) = payment_preimages.insert(hash, preimage) {
1650                                 return Err(DecodeError::InvalidValue);
1651                         }
1652                 }
1653
1654                 let last_block_hash: Sha256dHash = Readable::read(reader)?;
1655                 let destination_script = Readable::read(reader)?;
1656
1657                 Ok((last_block_hash.clone(), ChannelMonitor {
1658                         funding_txo,
1659                         commitment_transaction_number_obscure_factor,
1660
1661                         key_storage,
1662                         their_htlc_base_key,
1663                         their_delayed_payment_base_key,
1664                         their_cur_revocation_points,
1665
1666                         our_to_self_delay,
1667                         their_to_self_delay,
1668
1669                         old_secrets,
1670                         remote_claimable_outpoints,
1671                         remote_commitment_txn_on_chain,
1672                         remote_hash_commitment_number,
1673
1674                         prev_local_signed_commitment_tx,
1675                         current_local_signed_commitment_tx,
1676                         current_remote_commitment_number,
1677
1678                         payment_preimages,
1679
1680                         destination_script,
1681                         last_block_hash,
1682                         secp_ctx,
1683                         logger,
1684                 }))
1685         }
1686
1687 }
1688
1689 #[cfg(test)]
1690 mod tests {
1691         use bitcoin::blockdata::script::Script;
1692         use bitcoin::blockdata::transaction::Transaction;
1693         use crypto::digest::Digest;
1694         use hex;
1695         use ln::channelmonitor::ChannelMonitor;
1696         use ln::chan_utils::{HTLCOutputInCommitment, TxCreationKeys};
1697         use util::sha2::Sha256;
1698         use util::test_utils::TestLogger;
1699         use secp256k1::key::{SecretKey,PublicKey};
1700         use secp256k1::{Secp256k1, Signature};
1701         use rand::{thread_rng,Rng};
1702         use std::sync::Arc;
1703
1704         #[test]
1705         fn test_per_commitment_storage() {
1706                 // Test vectors from BOLT 3:
1707                 let mut secrets: Vec<[u8; 32]> = Vec::new();
1708                 let mut monitor: ChannelMonitor;
1709                 let secp_ctx = Secp256k1::new();
1710                 let logger = Arc::new(TestLogger::new());
1711
1712                 macro_rules! test_secrets {
1713                         () => {
1714                                 let mut idx = 281474976710655;
1715                                 for secret in secrets.iter() {
1716                                         assert_eq!(monitor.get_secret(idx).unwrap(), *secret);
1717                                         idx -= 1;
1718                                 }
1719                                 assert_eq!(monitor.get_min_seen_secret(), idx + 1);
1720                                 assert!(monitor.get_secret(idx).is_err());
1721                         };
1722                 }
1723
1724                 {
1725                         // insert_secret correct sequence
1726                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), 0, Script::new(), logger.clone());
1727                         secrets.clear();
1728
1729                         secrets.push([0; 32]);
1730                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1731                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1732                         test_secrets!();
1733
1734                         secrets.push([0; 32]);
1735                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1736                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1737                         test_secrets!();
1738
1739                         secrets.push([0; 32]);
1740                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1741                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1742                         test_secrets!();
1743
1744                         secrets.push([0; 32]);
1745                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1746                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
1747                         test_secrets!();
1748
1749                         secrets.push([0; 32]);
1750                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
1751                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
1752                         test_secrets!();
1753
1754                         secrets.push([0; 32]);
1755                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
1756                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
1757                         test_secrets!();
1758
1759                         secrets.push([0; 32]);
1760                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
1761                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
1762                         test_secrets!();
1763
1764                         secrets.push([0; 32]);
1765                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
1766                         monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap();
1767                         test_secrets!();
1768                 }
1769
1770                 {
1771                         // insert_secret #1 incorrect
1772                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), 0, Script::new(), logger.clone());
1773                         secrets.clear();
1774
1775                         secrets.push([0; 32]);
1776                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
1777                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1778                         test_secrets!();
1779
1780                         secrets.push([0; 32]);
1781                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1782                         assert_eq!(monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap_err().err,
1783                                         "Previous secret did not match new one");
1784                 }
1785
1786                 {
1787                         // insert_secret #2 incorrect (#1 derived from incorrect)
1788                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), 0, Script::new(), logger.clone());
1789                         secrets.clear();
1790
1791                         secrets.push([0; 32]);
1792                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
1793                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1794                         test_secrets!();
1795
1796                         secrets.push([0; 32]);
1797                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("dddc3a8d14fddf2b68fa8c7fbad2748274937479dd0f8930d5ebb4ab6bd866a3").unwrap());
1798                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1799                         test_secrets!();
1800
1801                         secrets.push([0; 32]);
1802                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1803                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1804                         test_secrets!();
1805
1806                         secrets.push([0; 32]);
1807                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1808                         assert_eq!(monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap_err().err,
1809                                         "Previous secret did not match new one");
1810                 }
1811
1812                 {
1813                         // insert_secret #3 incorrect
1814                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), 0, Script::new(), logger.clone());
1815                         secrets.clear();
1816
1817                         secrets.push([0; 32]);
1818                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1819                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1820                         test_secrets!();
1821
1822                         secrets.push([0; 32]);
1823                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1824                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1825                         test_secrets!();
1826
1827                         secrets.push([0; 32]);
1828                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c51a18b13e8527e579ec56365482c62f180b7d5760b46e9477dae59e87ed423a").unwrap());
1829                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1830                         test_secrets!();
1831
1832                         secrets.push([0; 32]);
1833                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1834                         assert_eq!(monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap_err().err,
1835                                         "Previous secret did not match new one");
1836                 }
1837
1838                 {
1839                         // insert_secret #4 incorrect (1,2,3 derived from incorrect)
1840                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), 0, Script::new(), logger.clone());
1841                         secrets.clear();
1842
1843                         secrets.push([0; 32]);
1844                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
1845                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1846                         test_secrets!();
1847
1848                         secrets.push([0; 32]);
1849                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("dddc3a8d14fddf2b68fa8c7fbad2748274937479dd0f8930d5ebb4ab6bd866a3").unwrap());
1850                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1851                         test_secrets!();
1852
1853                         secrets.push([0; 32]);
1854                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c51a18b13e8527e579ec56365482c62f180b7d5760b46e9477dae59e87ed423a").unwrap());
1855                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1856                         test_secrets!();
1857
1858                         secrets.push([0; 32]);
1859                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("ba65d7b0ef55a3ba300d4e87af29868f394f8f138d78a7011669c79b37b936f4").unwrap());
1860                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
1861                         test_secrets!();
1862
1863                         secrets.push([0; 32]);
1864                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
1865                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
1866                         test_secrets!();
1867
1868                         secrets.push([0; 32]);
1869                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
1870                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
1871                         test_secrets!();
1872
1873                         secrets.push([0; 32]);
1874                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
1875                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
1876                         test_secrets!();
1877
1878                         secrets.push([0; 32]);
1879                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
1880                         assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap_err().err,
1881                                         "Previous secret did not match new one");
1882                 }
1883
1884                 {
1885                         // insert_secret #5 incorrect
1886                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), 0, Script::new(), logger.clone());
1887                         secrets.clear();
1888
1889                         secrets.push([0; 32]);
1890                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1891                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1892                         test_secrets!();
1893
1894                         secrets.push([0; 32]);
1895                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1896                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1897                         test_secrets!();
1898
1899                         secrets.push([0; 32]);
1900                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1901                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1902                         test_secrets!();
1903
1904                         secrets.push([0; 32]);
1905                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1906                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
1907                         test_secrets!();
1908
1909                         secrets.push([0; 32]);
1910                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("631373ad5f9ef654bb3dade742d09504c567edd24320d2fcd68e3cc47e2ff6a6").unwrap());
1911                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
1912                         test_secrets!();
1913
1914                         secrets.push([0; 32]);
1915                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
1916                         assert_eq!(monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap_err().err,
1917                                         "Previous secret did not match new one");
1918                 }
1919
1920                 {
1921                         // insert_secret #6 incorrect (5 derived from incorrect)
1922                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), 0, Script::new(), logger.clone());
1923                         secrets.clear();
1924
1925                         secrets.push([0; 32]);
1926                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1927                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1928                         test_secrets!();
1929
1930                         secrets.push([0; 32]);
1931                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1932                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1933                         test_secrets!();
1934
1935                         secrets.push([0; 32]);
1936                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1937                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1938                         test_secrets!();
1939
1940                         secrets.push([0; 32]);
1941                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1942                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
1943                         test_secrets!();
1944
1945                         secrets.push([0; 32]);
1946                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("631373ad5f9ef654bb3dade742d09504c567edd24320d2fcd68e3cc47e2ff6a6").unwrap());
1947                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
1948                         test_secrets!();
1949
1950                         secrets.push([0; 32]);
1951                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("b7e76a83668bde38b373970155c868a653304308f9896692f904a23731224bb1").unwrap());
1952                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
1953                         test_secrets!();
1954
1955                         secrets.push([0; 32]);
1956                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
1957                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
1958                         test_secrets!();
1959
1960                         secrets.push([0; 32]);
1961                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
1962                         assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap_err().err,
1963                                         "Previous secret did not match new one");
1964                 }
1965
1966                 {
1967                         // insert_secret #7 incorrect
1968                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), 0, Script::new(), logger.clone());
1969                         secrets.clear();
1970
1971                         secrets.push([0; 32]);
1972                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1973                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1974                         test_secrets!();
1975
1976                         secrets.push([0; 32]);
1977                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1978                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1979                         test_secrets!();
1980
1981                         secrets.push([0; 32]);
1982                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1983                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1984                         test_secrets!();
1985
1986                         secrets.push([0; 32]);
1987                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1988                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
1989                         test_secrets!();
1990
1991                         secrets.push([0; 32]);
1992                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
1993                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
1994                         test_secrets!();
1995
1996                         secrets.push([0; 32]);
1997                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
1998                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
1999                         test_secrets!();
2000
2001                         secrets.push([0; 32]);
2002                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("e7971de736e01da8ed58b94c2fc216cb1dca9e326f3a96e7194fe8ea8af6c0a3").unwrap());
2003                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
2004                         test_secrets!();
2005
2006                         secrets.push([0; 32]);
2007                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
2008                         assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap_err().err,
2009                                         "Previous secret did not match new one");
2010                 }
2011
2012                 {
2013                         // insert_secret #8 incorrect
2014                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), 0, Script::new(), logger.clone());
2015                         secrets.clear();
2016
2017                         secrets.push([0; 32]);
2018                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2019                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2020                         test_secrets!();
2021
2022                         secrets.push([0; 32]);
2023                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2024                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2025                         test_secrets!();
2026
2027                         secrets.push([0; 32]);
2028                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2029                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2030                         test_secrets!();
2031
2032                         secrets.push([0; 32]);
2033                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2034                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
2035                         test_secrets!();
2036
2037                         secrets.push([0; 32]);
2038                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
2039                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
2040                         test_secrets!();
2041
2042                         secrets.push([0; 32]);
2043                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
2044                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
2045                         test_secrets!();
2046
2047                         secrets.push([0; 32]);
2048                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
2049                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
2050                         test_secrets!();
2051
2052                         secrets.push([0; 32]);
2053                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a7efbc61aac46d34f77778bac22c8a20c6a46ca460addc49009bda875ec88fa4").unwrap());
2054                         assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap_err().err,
2055                                         "Previous secret did not match new one");
2056                 }
2057         }
2058
2059         #[test]
2060         fn test_prune_preimages() {
2061                 let secp_ctx = Secp256k1::new();
2062                 let logger = Arc::new(TestLogger::new());
2063                 let dummy_sig = Signature::from_der(&secp_ctx, &hex::decode("3045022100fa86fa9a36a8cd6a7bb8f06a541787d51371d067951a9461d5404de6b928782e02201c8b7c334c10aed8976a3a465be9a28abff4cb23acbf00022295b378ce1fa3cd").unwrap()[..]).unwrap();
2064
2065                 macro_rules! dummy_keys {
2066                         () => {
2067                                 {
2068                                         let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap());
2069                                         TxCreationKeys {
2070                                                 per_commitment_point: dummy_key.clone(),
2071                                                 revocation_key: dummy_key.clone(),
2072                                                 a_htlc_key: dummy_key.clone(),
2073                                                 b_htlc_key: dummy_key.clone(),
2074                                                 a_delayed_payment_key: dummy_key.clone(),
2075                                                 b_payment_key: dummy_key.clone(),
2076                                         }
2077                                 }
2078                         }
2079                 }
2080                 let dummy_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
2081
2082                 let mut preimages = Vec::new();
2083                 {
2084                         let mut rng  = thread_rng();
2085                         for _ in 0..20 {
2086                                 let mut preimage = [0; 32];
2087                                 rng.fill_bytes(&mut preimage);
2088                                 let mut sha = Sha256::new();
2089                                 sha.input(&preimage);
2090                                 let mut hash = [0; 32];
2091                                 sha.result(&mut hash);
2092                                 preimages.push((preimage, hash));
2093                         }
2094                 }
2095
2096                 macro_rules! preimages_slice_to_htlc_outputs {
2097                         ($preimages_slice: expr) => {
2098                                 {
2099                                         let mut res = Vec::new();
2100                                         for (idx, preimage) in $preimages_slice.iter().enumerate() {
2101                                                 res.push(HTLCOutputInCommitment {
2102                                                         offered: true,
2103                                                         amount_msat: 0,
2104                                                         cltv_expiry: 0,
2105                                                         payment_hash: preimage.1.clone(),
2106                                                         transaction_output_index: idx as u32,
2107                                                 });
2108                                         }
2109                                         res
2110                                 }
2111                         }
2112                 }
2113                 macro_rules! preimages_to_local_htlcs {
2114                         ($preimages_slice: expr) => {
2115                                 {
2116                                         let mut inp = preimages_slice_to_htlc_outputs!($preimages_slice);
2117                                         let res: Vec<_> = inp.drain(..).map(|e| { (e, dummy_sig.clone(), dummy_sig.clone()) }).collect();
2118                                         res
2119                                 }
2120                         }
2121                 }
2122
2123                 macro_rules! test_preimages_exist {
2124                         ($preimages_slice: expr, $monitor: expr) => {
2125                                 for preimage in $preimages_slice {
2126                                         assert!($monitor.payment_preimages.contains_key(&preimage.1));
2127                                 }
2128                         }
2129                 }
2130
2131                 // Prune with one old state and a local commitment tx holding a few overlaps with the
2132                 // old state.
2133                 let mut monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), 0, Script::new(), logger.clone());
2134                 monitor.set_their_to_self_delay(10);
2135
2136                 monitor.provide_latest_local_commitment_tx_info(dummy_tx.clone(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..10]));
2137                 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[5..15]), 281474976710655);
2138                 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[15..20]), 281474976710654);
2139                 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[17..20]), 281474976710653);
2140                 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[18..20]), 281474976710652);
2141                 for &(ref preimage, ref hash) in preimages.iter() {
2142                         monitor.provide_payment_preimage(hash, preimage);
2143                 }
2144
2145                 // Now provide a secret, pruning preimages 10-15
2146                 let mut secret = [0; 32];
2147                 secret[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2148                 monitor.provide_secret(281474976710655, secret.clone()).unwrap();
2149                 assert_eq!(monitor.payment_preimages.len(), 15);
2150                 test_preimages_exist!(&preimages[0..10], monitor);
2151                 test_preimages_exist!(&preimages[15..20], monitor);
2152
2153                 // Now provide a further secret, pruning preimages 15-17
2154                 secret[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2155                 monitor.provide_secret(281474976710654, secret.clone()).unwrap();
2156                 assert_eq!(monitor.payment_preimages.len(), 13);
2157                 test_preimages_exist!(&preimages[0..10], monitor);
2158                 test_preimages_exist!(&preimages[17..20], monitor);
2159
2160                 // Now update local commitment tx info, pruning only element 18 as we still care about the
2161                 // previous commitment tx's preimages too
2162                 monitor.provide_latest_local_commitment_tx_info(dummy_tx.clone(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..5]));
2163                 secret[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2164                 monitor.provide_secret(281474976710653, secret.clone()).unwrap();
2165                 assert_eq!(monitor.payment_preimages.len(), 12);
2166                 test_preimages_exist!(&preimages[0..10], monitor);
2167                 test_preimages_exist!(&preimages[18..20], monitor);
2168
2169                 // But if we do it again, we'll prune 5-10
2170                 monitor.provide_latest_local_commitment_tx_info(dummy_tx.clone(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..3]));
2171                 secret[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2172                 monitor.provide_secret(281474976710652, secret.clone()).unwrap();
2173                 assert_eq!(monitor.payment_preimages.len(), 5);
2174                 test_preimages_exist!(&preimages[0..5], monitor);
2175         }
2176
2177         // Further testing is done in the ChannelManager integration tests.
2178 }