_ 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 latest ChannelMonitor must always be actively monitoring for chain updates (and no out-of-date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, Builder};
  18 use bitcoin::blockdata::opcodes;
  19 use bitcoin::consensus::encode::{self, Decodable, Encodable};
  20 use bitcoin::util::hash::{Hash160, BitcoinHash,Sha256dHash};
  21 use bitcoin::util::bip143;
  22
  23 use crypto::digest::Digest;
  24
  25 use secp256k1::{Secp256k1,Message,Signature};
  26 use secp256k1::key::{SecretKey,PublicKey};
  27 use secp256k1;
  28
  29 use ln::msgs::{DecodeError, HandleError};
  30 use ln::chan_utils;
  31 use ln::chan_utils::HTLCOutputInCommitment;
  32 use chain::chaininterface::{ChainListener, ChainWatchInterface, BroadcasterInterface};
  33 use chain::transaction::OutPoint;
  34 use chain::keysinterface::SpendableOutputDescriptor;
  35 use util::logger::Logger;
  36 use util::ser::{ReadableArgs, Readable, Writer, Writeable, WriterWriteAdaptor, U48};
  37 use util::sha2::Sha256;
  38 use util::{byte_utils, events};
  39
  40 use std::collections::HashMap;
  41 use std::sync::{Arc,Mutex};
  42 use std::{hash,cmp, mem};
  43
  44 /// An error enum representing a failure to persist a channel monitor update.
  45 #[derive(Clone)]
  46 pub enum ChannelMonitorUpdateErr {
  47         /// Used to indicate a temporary failure (eg connection to a watchtower failed, but is expected
  48         /// to succeed at some point in the future).
  49         ///
  50         /// Such a failure will "freeze" a channel, preventing us from revoking old states or
  51         /// submitting new commitment transactions to the remote party.
  52         /// ChannelManager::test_restore_channel_monitor can be used to retry the update(s) and restore
  53         /// the channel to an operational state.
  54         ///
  55         /// Note that continuing to operate when no copy of the updated ChannelMonitor could be
  56         /// persisted is unsafe - if you failed to store the update on your own local disk you should
  57         /// instead return PermanentFailure to force closure of the channel ASAP.
  58         ///
  59         /// Even when a channel has been "frozen" updates to the ChannelMonitor can continue to occur
  60         /// (eg if an inbound HTLC which we forwarded was claimed upstream resulting in us attempting
  61         /// to claim it on this channel) and those updates must be applied wherever they can be. At
  62         /// least one such updated ChannelMonitor must be persisted otherwise PermanentFailure should
  63         /// be returned to get things on-chain ASAP using only the in-memory copy. Obviously updates to
  64         /// the channel which would invalidate previous ChannelMonitors are not made when a channel has
  65         /// been "frozen".
  66         ///
  67         /// Note that even if updates made after TemporaryFailure succeed you must still call
  68         /// test_restore_channel_monitor to ensure you have the latest monitor and re-enable normal
  69         /// channel operation.
  70         TemporaryFailure,
  71         /// Used to indicate no further channel monitor updates will be allowed (eg we've moved on to a
  72         /// different watchtower and cannot update with all watchtowers that were previously informed
  73         /// of this channel). This will force-close the channel in question.
  74         PermanentFailure,
  75 }
  76
  77 /// Simple trait indicating ability to track a set of ChannelMonitors and multiplex events between
  78 /// them. Generally should be implemented by keeping a local SimpleManyChannelMonitor and passing
  79 /// events to it, while also taking any add_update_monitor events and passing them to some remote
  80 /// server(s).
  81 ///
  82 /// Note that any updates to a channel's monitor *must* be applied to each instance of the
  83 /// channel's monitor everywhere (including remote watchtowers) *before* this function returns. If
  84 /// an update occurs and a remote watchtower is left with old state, it may broadcast transactions
  85 /// which we have revoked, allowing our counterparty to claim all funds in the channel!
  86 pub trait ManyChannelMonitor: Send + Sync {
  87         /// Adds or updates a monitor for the given `funding_txo`.
  88         ///
  89         /// Implementor must also ensure that the funding_txo outpoint is registered with any relevant
  90         /// ChainWatchInterfaces such that the provided monitor receives block_connected callbacks with
  91         /// any spends of it.
  92         fn add_update_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor) -> Result<(), ChannelMonitorUpdateErr>;
  93 }
  94
  95 /// A simple implementation of a ManyChannelMonitor and ChainListener. Can be used to create a
  96 /// watchtower or watch our own channels.
  97 ///
  98 /// Note that you must provide your own key by which to refer to channels.
  99 ///
 100 /// If you're accepting remote monitors (ie are implementing a watchtower), you must verify that
 101 /// users cannot overwrite a given channel by providing a duplicate key. ie you should probably
 102 /// index by a PublicKey which is required to sign any updates.
 103 ///
 104 /// If you're using this for local monitoring of your own channels, you probably want to use
 105 /// `OutPoint` as the key, which will give you a ManyChannelMonitor implementation.
 106 pub struct SimpleManyChannelMonitor<Key> {
 107         #[cfg(test)] // Used in ChannelManager tests to manipulate channels directly
 108         pub monitors: Mutex<HashMap<Key, ChannelMonitor>>,
 109         #[cfg(not(test))]
 110         monitors: Mutex<HashMap<Key, ChannelMonitor>>,
 111         chain_monitor: Arc<ChainWatchInterface>,
 112         broadcaster: Arc<BroadcasterInterface>,
 113         pending_events: Mutex<Vec<events::Event>>,
 114         logger: Arc<Logger>,
 115 }
 116
 117 impl<Key : Send + cmp::Eq + hash::Hash> ChainListener for SimpleManyChannelMonitor<Key> {
 118         fn block_connected(&self, header: &BlockHeader, height: u32, txn_matched: &[&Transaction], _indexes_of_txn_matched: &[u32]) {
 119                 let block_hash = header.bitcoin_hash();
 120                 let mut new_events: Vec<events::Event> = Vec::with_capacity(0);
 121                 {
 122                         let mut monitors = self.monitors.lock().unwrap();
 123                         for monitor in monitors.values_mut() {
 124                                 let (txn_outputs, spendable_outputs) = monitor.block_connected(txn_matched, height, &block_hash, &*self.broadcaster);
 125                                 if spendable_outputs.len() > 0 {
 126                                         new_events.push(events::Event::SpendableOutputs {
 127                                                 outputs: spendable_outputs,
 128                                         });
 129                                 }
 130                                 for (ref txid, ref outputs) in txn_outputs {
 131                                         for (idx, output) in outputs.iter().enumerate() {
 132                                                 self.chain_monitor.install_watch_outpoint((txid.clone(), idx as u32), &output.script_pubkey);
 133                                         }
 134                                 }
 135                         }
 136                 }
 137                 let mut pending_events = self.pending_events.lock().unwrap();
 138                 pending_events.append(&mut new_events);
 139         }
 140
 141         fn block_disconnected(&self, _: &BlockHeader) { }
 142 }
 143
 144 impl<Key : Send + cmp::Eq + hash::Hash + 'static> SimpleManyChannelMonitor<Key> {
 145         /// Creates a new object which can be used to monitor several channels given the chain
 146         /// interface with which to register to receive notifications.
 147         pub fn new(chain_monitor: Arc<ChainWatchInterface>, broadcaster: Arc<BroadcasterInterface>, logger: Arc<Logger>) -> Arc<SimpleManyChannelMonitor<Key>> {
 148                 let res = Arc::new(SimpleManyChannelMonitor {
 149                         monitors: Mutex::new(HashMap::new()),
 150                         chain_monitor,
 151                         broadcaster,
 152                         pending_events: Mutex::new(Vec::new()),
 153                         logger,
 154                 });
 155                 let weak_res = Arc::downgrade(&res);
 156                 res.chain_monitor.register_listener(weak_res);
 157                 res
 158         }
 159
 160         /// Adds or udpates the monitor which monitors the channel referred to by the given key.
 161         pub fn add_update_monitor_by_key(&self, key: Key, monitor: ChannelMonitor) -> Result<(), HandleError> {
 162                 let mut monitors = self.monitors.lock().unwrap();
 163                 match monitors.get_mut(&key) {
 164                         Some(orig_monitor) => {
 165                                 log_trace!(self, "Updating Channel Monitor for channel {}", log_funding_option!(monitor.funding_txo));
 166                                 return orig_monitor.insert_combine(monitor);
 167                         },
 168                         None => {}
 169                 };
 170                 match &monitor.funding_txo {
 171                         &None => {
 172                                 log_trace!(self, "Got new Channel Monitor for no-funding-set channel (monitoring all txn!)");
 173                                 self.chain_monitor.watch_all_txn()
 174                         },
 175                         &Some((ref outpoint, ref script)) => {
 176                                 log_trace!(self, "Got new Channel Monitor for channel {}", log_bytes!(outpoint.to_channel_id()[..]));
 177                                 self.chain_monitor.install_watch_tx(&outpoint.txid, script);
 178                                 self.chain_monitor.install_watch_outpoint((outpoint.txid, outpoint.index as u32), script);
 179                         },
 180                 }
 181                 monitors.insert(key, monitor);
 182                 Ok(())
 183         }
 184 }
 185
 186 impl ManyChannelMonitor for SimpleManyChannelMonitor<OutPoint> {
 187         fn add_update_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor) -> Result<(), ChannelMonitorUpdateErr> {
 188                 match self.add_update_monitor_by_key(funding_txo, monitor) {
 189                         Ok(_) => Ok(()),
 190                         Err(_) => Err(ChannelMonitorUpdateErr::PermanentFailure),
 191                 }
 192         }
 193 }
 194
 195 impl<Key : Send + cmp::Eq + hash::Hash> events::EventsProvider for SimpleManyChannelMonitor<Key> {
 196         fn get_and_clear_pending_events(&self) -> Vec<events::Event> {
 197                 let mut pending_events = self.pending_events.lock().unwrap();
 198                 let mut ret = Vec::new();
 199                 mem::swap(&mut ret, &mut *pending_events);
 200                 ret
 201         }
 202 }
 203
 204 /// If an HTLC expires within this many blocks, don't try to claim it in a shared transaction,
 205 /// instead claiming it in its own individual transaction.
 206 const CLTV_SHARED_CLAIM_BUFFER: u32 = 12;
 207 /// If an HTLC expires within this many blocks, force-close the channel to broadcast the
 208 /// HTLC-Success transaction.
 209 /// In other words, this is an upper bound on how many blocks we think it can take us to get a
 210 /// transaction confirmed (and we use it in a few more, equivalent, places).
 211 pub(crate) const CLTV_CLAIM_BUFFER: u32 = 6;
 212 /// Number of blocks by which point we expect our counterparty to have seen new blocks on the
 213 /// network and done a full update_fail_htlc/commitment_signed dance (+ we've updated all our
 214 /// copies of ChannelMonitors, including watchtowers).
 215 pub(crate) const HTLC_FAIL_TIMEOUT_BLOCKS: u32 = 3;
 216
 217 #[derive(Clone, PartialEq)]
 218 enum KeyStorage {
 219         PrivMode {
 220                 revocation_base_key: SecretKey,
 221                 htlc_base_key: SecretKey,
 222                 delayed_payment_base_key: SecretKey,
 223                 payment_base_key: SecretKey,
 224                 shutdown_pubkey: PublicKey,
 225                 prev_latest_per_commitment_point: Option<PublicKey>,
 226                 latest_per_commitment_point: Option<PublicKey>,
 227         },
 228         SigsMode {
 229                 revocation_base_key: PublicKey,
 230                 htlc_base_key: PublicKey,
 231                 sigs: HashMap<Sha256dHash, Signature>,
 232         }
 233 }
 234
 235 #[derive(Clone, PartialEq)]
 236 struct LocalSignedTx {
 237         /// txid of the transaction in tx, just used to make comparison faster
 238         txid: Sha256dHash,
 239         tx: Transaction,
 240         revocation_key: PublicKey,
 241         a_htlc_key: PublicKey,
 242         b_htlc_key: PublicKey,
 243         delayed_payment_key: PublicKey,
 244         feerate_per_kw: u64,
 245         htlc_outputs: Vec<(HTLCOutputInCommitment, Signature, Signature)>,
 246 }
 247
 248 const SERIALIZATION_VERSION: u8 = 1;
 249 const MIN_SERIALIZATION_VERSION: u8 = 1;
 250
 251 /// A ChannelMonitor handles chain events (blocks connected and disconnected) and generates
 252 /// on-chain transactions to ensure no loss of funds occurs.
 253 ///
 254 /// You MUST ensure that no ChannelMonitors for a given channel anywhere contain out-of-date
 255 /// information and are actively monitoring the chain.
 256 #[derive(Clone)]
 257 pub struct ChannelMonitor {
 258         funding_txo: Option<(OutPoint, Script)>,
 259         commitment_transaction_number_obscure_factor: u64,
 260
 261         key_storage: KeyStorage,
 262         their_htlc_base_key: Option<PublicKey>,
 263         their_delayed_payment_base_key: Option<PublicKey>,
 264         // first is the idx of the first of the two revocation points
 265         their_cur_revocation_points: Option<(u64, PublicKey, Option<PublicKey>)>,
 266
 267         our_to_self_delay: u16,
 268         their_to_self_delay: Option<u16>,
 269
 270         old_secrets: [([u8; 32], u64); 49],
 271         remote_claimable_outpoints: HashMap<Sha256dHash, Vec<HTLCOutputInCommitment>>,
 272         /// We cannot identify HTLC-Success or HTLC-Timeout transactions by themselves on the chain.
 273         /// Nor can we figure out their commitment numbers without the commitment transaction they are
 274         /// spending. Thus, in order to claim them via revocation key, we track all the remote
 275         /// commitment transactions which we find on-chain, mapping them to the commitment number which
 276         /// can be used to derive the revocation key and claim the transactions.
 277         remote_commitment_txn_on_chain: HashMap<Sha256dHash, (u64, Vec<Script>)>,
 278         /// Cache used to make pruning of payment_preimages faster.
 279         /// Maps payment_hash values to commitment numbers for remote transactions for non-revoked
 280         /// remote transactions (ie should remain pretty small).
 281         /// Serialized to disk but should generally not be sent to Watchtowers.
 282         remote_hash_commitment_number: HashMap<[u8; 32], u64>,
 283
 284         // We store two local commitment transactions to avoid any race conditions where we may update
 285         // some monitors (potentially on watchtowers) but then fail to update others, resulting in the
 286         // various monitors for one channel being out of sync, and us broadcasting a local
 287         // transaction for which we have deleted claim information on some watchtowers.
 288         prev_local_signed_commitment_tx: Option<LocalSignedTx>,
 289         current_local_signed_commitment_tx: Option<LocalSignedTx>,
 290
 291         // Used just for ChannelManager to make sure it has the latest channel data during
 292         // deserialization
 293         current_remote_commitment_number: u64,
 294
 295         payment_preimages: HashMap<[u8; 32], [u8; 32]>,
 296
 297         destination_script: Script,
 298
 299         // We simply modify last_block_hash in Channel's block_connected so that serialization is
 300         // consistent but hopefully the users' copy handles block_connected in a consistent way.
 301         // (we do *not*, however, update them in insert_combine to ensure any local user copies keep
 302         // their last_block_hash from its state and not based on updated copies that didn't run through
 303         // the full block_connected).
 304         pub(crate) last_block_hash: Sha256dHash,
 305         secp_ctx: Secp256k1<secp256k1::All>, //TODO: dedup this a bit...
 306         logger: Arc<Logger>,
 307 }
 308
 309 #[cfg(any(test, feature = "fuzztarget"))]
 310 /// Used only in testing and fuzztarget to check serialization roundtrips don't change the
 311 /// underlying object
 312 impl PartialEq for ChannelMonitor {
 313         fn eq(&self, other: &Self) -> bool {
 314                 if self.funding_txo != other.funding_txo ||
 315                         self.commitment_transaction_number_obscure_factor != other.commitment_transaction_number_obscure_factor ||
 316                         self.key_storage != other.key_storage ||
 317                         self.their_htlc_base_key != other.their_htlc_base_key ||
 318                         self.their_delayed_payment_base_key != other.their_delayed_payment_base_key ||
 319                         self.their_cur_revocation_points != other.their_cur_revocation_points ||
 320                         self.our_to_self_delay != other.our_to_self_delay ||
 321                         self.their_to_self_delay != other.their_to_self_delay ||
 322                         self.remote_claimable_outpoints != other.remote_claimable_outpoints ||
 323                         self.remote_commitment_txn_on_chain != other.remote_commitment_txn_on_chain ||
 324                         self.remote_hash_commitment_number != other.remote_hash_commitment_number ||
 325                         self.prev_local_signed_commitment_tx != other.prev_local_signed_commitment_tx ||
 326                         self.current_remote_commitment_number != other.current_remote_commitment_number ||
 327                         self.current_local_signed_commitment_tx != other.current_local_signed_commitment_tx ||
 328                         self.payment_preimages != other.payment_preimages ||
 329                         self.destination_script != other.destination_script
 330                 {
 331                         false
 332                 } else {
 333                         for (&(ref secret, ref idx), &(ref o_secret, ref o_idx)) in self.old_secrets.iter().zip(other.old_secrets.iter()) {
 334                                 if secret != o_secret || idx != o_idx {
 335                                         return false
 336                                 }
 337                         }
 338                         true
 339                 }
 340         }
 341 }
 342
 343 impl ChannelMonitor {
 344         pub(super) fn new(revocation_base_key: &SecretKey, delayed_payment_base_key: &SecretKey, htlc_base_key: &SecretKey, payment_base_key: &SecretKey, shutdown_pubkey: &PublicKey, our_to_self_delay: u16, destination_script: Script, logger: Arc<Logger>) -> ChannelMonitor {
 345                 ChannelMonitor {
 346                         funding_txo: None,
 347                         commitment_transaction_number_obscure_factor: 0,
 348
 349                         key_storage: KeyStorage::PrivMode {
 350                                 revocation_base_key: revocation_base_key.clone(),
 351                                 htlc_base_key: htlc_base_key.clone(),
 352                                 delayed_payment_base_key: delayed_payment_base_key.clone(),
 353                                 payment_base_key: payment_base_key.clone(),
 354                                 shutdown_pubkey: shutdown_pubkey.clone(),
 355                                 prev_latest_per_commitment_point: None,
 356                                 latest_per_commitment_point: None,
 357                         },
 358                         their_htlc_base_key: None,
 359                         their_delayed_payment_base_key: None,
 360                         their_cur_revocation_points: None,
 361
 362                         our_to_self_delay: our_to_self_delay,
 363                         their_to_self_delay: None,
 364
 365                         old_secrets: [([0; 32], 1 << 48); 49],
 366                         remote_claimable_outpoints: HashMap::new(),
 367                         remote_commitment_txn_on_chain: HashMap::new(),
 368                         remote_hash_commitment_number: HashMap::new(),
 369
 370                         prev_local_signed_commitment_tx: None,
 371                         current_local_signed_commitment_tx: None,
 372                         current_remote_commitment_number: 1 << 48,
 373
 374                         payment_preimages: HashMap::new(),
 375                         destination_script: destination_script,
 376
 377                         last_block_hash: Default::default(),
 378                         secp_ctx: Secp256k1::new(),
 379                         logger,
 380                 }
 381         }
 382
 383         #[inline]
 384         fn place_secret(idx: u64) -> u8 {
 385                 for i in 0..48 {
 386                         if idx & (1 << i) == (1 << i) {
 387                                 return i
 388                         }
 389                 }
 390                 48
 391         }
 392
 393         #[inline]
 394         fn derive_secret(secret: [u8; 32], bits: u8, idx: u64) -> [u8; 32] {
 395                 let mut res: [u8; 32] = secret;
 396                 for i in 0..bits {
 397                         let bitpos = bits - 1 - i;
 398                         if idx & (1 << bitpos) == (1 << bitpos) {
 399                                 res[(bitpos / 8) as usize] ^= 1 << (bitpos & 7);
 400                                 let mut sha = Sha256::new();
 401                                 sha.input(&res);
 402                                 sha.result(&mut res);
 403                         }
 404                 }
 405                 res
 406         }
 407
 408         /// Inserts a revocation secret into this channel monitor. Prunes old preimages if neither
 409         /// needed by local commitment transactions HTCLs nor by remote ones. Unless we haven't already seen remote
 410         /// commitment transaction's secret, they are de facto pruned (we can use revocation key).
 411         pub(super) fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), HandleError> {
 412                 let pos = ChannelMonitor::place_secret(idx);
 413                 for i in 0..pos {
 414                         let (old_secret, old_idx) = self.old_secrets[i as usize];
 415                         if ChannelMonitor::derive_secret(secret, pos, old_idx) != old_secret {
 416                                 return Err(HandleError{err: "Previous secret did not match new one", action: None})
 417                         }
 418                 }
 419                 self.old_secrets[pos as usize] = (secret, idx);
 420
 421                 if !self.payment_preimages.is_empty() {
 422                         let local_signed_commitment_tx = self.current_local_signed_commitment_tx.as_ref().expect("Channel needs at least an initial commitment tx !");
 423                         let prev_local_signed_commitment_tx = self.prev_local_signed_commitment_tx.as_ref();
 424                         let min_idx = self.get_min_seen_secret();
 425                         let remote_hash_commitment_number = &mut self.remote_hash_commitment_number;
 426
 427                         self.payment_preimages.retain(|&k, _| {
 428                                 for &(ref htlc, _, _) in &local_signed_commitment_tx.htlc_outputs {
 429                                         if k == htlc.payment_hash {
 430                                                 return true
 431                                         }
 432                                 }
 433                                 if let Some(prev_local_commitment_tx) = prev_local_signed_commitment_tx {
 434                                         for &(ref htlc, _, _) in prev_local_commitment_tx.htlc_outputs.iter() {
 435                                                 if k == htlc.payment_hash {
 436                                                         return true
 437                                                 }
 438                                         }
 439                                 }
 440                                 let contains = if let Some(cn) = remote_hash_commitment_number.get(&k) {
 441                                         if *cn < min_idx {
 442                                                 return true
 443                                         }
 444                                         true
 445                                 } else { false };
 446                                 if contains {
 447                                         remote_hash_commitment_number.remove(&k);
 448                                 }
 449                                 false
 450                         });
 451                 }
 452
 453                 Ok(())
 454         }
 455
 456         /// Tracks the next revocation point which may be required to claim HTLC outputs which we know
 457         /// the preimage of in case the remote end force-closes using their latest state. When called at
 458         /// channel opening revocation point is the CURRENT one used for first commitment tx. Needed in case of sizeable push_msat.
 459         pub(super) fn provide_their_next_revocation_point(&mut self, their_next_revocation_point: Option<(u64, PublicKey)>) {
 460                 if let Some(new_revocation_point) = their_next_revocation_point {
 461                         match self.their_cur_revocation_points {
 462                                 Some(old_points) => {
 463                                         if old_points.0 == new_revocation_point.0 + 1 {
 464                                                 self.their_cur_revocation_points = Some((old_points.0, old_points.1, Some(new_revocation_point.1)));
 465                                         } else if old_points.0 == new_revocation_point.0 + 2 {
 466                                                 if let Some(old_second_point) = old_points.2 {
 467                                                         self.their_cur_revocation_points = Some((old_points.0 - 1, old_second_point, Some(new_revocation_point.1)));
 468                                                 } else {
 469                                                         self.their_cur_revocation_points = Some((new_revocation_point.0, new_revocation_point.1, None));
 470                                                 }
 471                                         } else {
 472                                                 self.their_cur_revocation_points = Some((new_revocation_point.0, new_revocation_point.1, None));
 473                                         }
 474                                 },
 475                                 None => {
 476                                         self.their_cur_revocation_points = Some((new_revocation_point.0, new_revocation_point.1, None));
 477                                 }
 478                         }
 479                 }
 480         }
 481
 482         /// Informs this monitor of the latest remote (ie non-broadcastable) commitment transaction.
 483         /// The monitor watches for it to be broadcasted and then uses the HTLC information (and
 484         /// possibly future revocation/preimage information) to claim outputs where possible.
 485         /// We cache also the mapping hash:commitment number to lighten pruning of old preimages by watchtowers.
 486         pub(super) fn provide_latest_remote_commitment_tx_info(&mut self, unsigned_commitment_tx: &Transaction, htlc_outputs: Vec<HTLCOutputInCommitment>, commitment_number: u64) {
 487                 // TODO: Encrypt the htlc_outputs data with the single-hash of the commitment transaction
 488                 // so that a remote monitor doesn't learn anything unless there is a malicious close.
 489                 // (only maybe, sadly we cant do the same for local info, as we need to be aware of
 490                 // timeouts)
 491                 for htlc in &htlc_outputs {
 492                         self.remote_hash_commitment_number.insert(htlc.payment_hash, commitment_number);
 493                 }
 494                 self.remote_claimable_outpoints.insert(unsigned_commitment_tx.txid(), htlc_outputs);
 495                 self.current_remote_commitment_number = commitment_number;
 496         }
 497
 498         /// Informs this monitor of the latest local (ie broadcastable) commitment transaction. The
 499         /// monitor watches for timeouts and may broadcast it if we approach such a timeout. Thus, it
 500         /// is important that any clones of this channel monitor (including remote clones) by kept
 501         /// up-to-date as our local commitment transaction is updated.
 502         /// Panics if set_their_to_self_delay has never been called.
 503         /// Also update KeyStorage with latest local per_commitment_point to derive local_delayedkey in
 504         /// case of onchain HTLC tx
 505         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)>) {
 506                 assert!(self.their_to_self_delay.is_some());
 507                 self.prev_local_signed_commitment_tx = self.current_local_signed_commitment_tx.take();
 508                 self.current_local_signed_commitment_tx = Some(LocalSignedTx {
 509                         txid: signed_commitment_tx.txid(),
 510                         tx: signed_commitment_tx,
 511                         revocation_key: local_keys.revocation_key,
 512                         a_htlc_key: local_keys.a_htlc_key,
 513                         b_htlc_key: local_keys.b_htlc_key,
 514                         delayed_payment_key: local_keys.a_delayed_payment_key,
 515                         feerate_per_kw,
 516                         htlc_outputs,
 517                 });
 518                 self.key_storage = if let KeyStorage::PrivMode { ref revocation_base_key, ref htlc_base_key, ref delayed_payment_base_key, ref payment_base_key, ref shutdown_pubkey, ref latest_per_commitment_point, .. } = self.key_storage {
 519                         KeyStorage::PrivMode {
 520                                 revocation_base_key: *revocation_base_key,
 521                                 htlc_base_key: *htlc_base_key,
 522                                 delayed_payment_base_key: *delayed_payment_base_key,
 523                                 payment_base_key: *payment_base_key,
 524                                 shutdown_pubkey: *shutdown_pubkey,
 525                                 prev_latest_per_commitment_point: *latest_per_commitment_point,
 526                                 latest_per_commitment_point: Some(local_keys.per_commitment_point),
 527                         }
 528                 } else { unimplemented!(); };
 529         }
 530
 531         /// Provides a payment_hash->payment_preimage mapping. Will be automatically pruned when all
 532         /// commitment_tx_infos which contain the payment hash have been revoked.
 533         pub(super) fn provide_payment_preimage(&mut self, payment_hash: &[u8; 32], payment_preimage: &[u8; 32]) {
 534                 self.payment_preimages.insert(payment_hash.clone(), payment_preimage.clone());
 535         }
 536
 537         /// Combines this ChannelMonitor with the information contained in the other ChannelMonitor.
 538         /// After a successful call this ChannelMonitor is up-to-date and is safe to use to monitor the
 539         /// chain for new blocks/transactions.
 540         pub fn insert_combine(&mut self, mut other: ChannelMonitor) -> Result<(), HandleError> {
 541                 if self.funding_txo.is_some() {
 542                         // We should be able to compare the entire funding_txo, but in fuzztarget its trivially
 543                         // easy to collide the funding_txo hash and have a different scriptPubKey.
 544                         if other.funding_txo.is_some() && other.funding_txo.as_ref().unwrap().0 != self.funding_txo.as_ref().unwrap().0 {
 545                                 return Err(HandleError{err: "Funding transaction outputs are not identical!", action: None});
 546                         }
 547                 } else {
 548                         self.funding_txo = other.funding_txo.take();
 549                 }
 550                 let other_min_secret = other.get_min_seen_secret();
 551                 let our_min_secret = self.get_min_seen_secret();
 552                 if our_min_secret > other_min_secret {
 553                         self.provide_secret(other_min_secret, other.get_secret(other_min_secret).unwrap())?;
 554                 }
 555                 if let Some(ref local_tx) = self.current_local_signed_commitment_tx {
 556                         if let Some(ref other_local_tx) = other.current_local_signed_commitment_tx {
 557                                 let our_commitment_number = 0xffffffffffff - ((((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);
 558                                 let other_commitment_number = 0xffffffffffff - ((((other_local_tx.tx.input[0].sequence as u64 & 0xffffff) << 3*8) | (other_local_tx.tx.lock_time as u64 & 0xffffff)) ^ other.commitment_transaction_number_obscure_factor);
 559                                 if our_commitment_number >= other_commitment_number {
 560                                         self.key_storage = other.key_storage;
 561                                 }
 562                         }
 563                 }
 564                 // TODO: We should use current_remote_commitment_number and the commitment number out of
 565                 // local transactions to decide how to merge
 566                 if our_min_secret >= other_min_secret {
 567                         self.their_cur_revocation_points = other.their_cur_revocation_points;
 568                         for (txid, htlcs) in other.remote_claimable_outpoints.drain() {
 569                                 self.remote_claimable_outpoints.insert(txid, htlcs);
 570                         }
 571                         if let Some(local_tx) = other.prev_local_signed_commitment_tx {
 572                                 self.prev_local_signed_commitment_tx = Some(local_tx);
 573                         }
 574                         if let Some(local_tx) = other.current_local_signed_commitment_tx {
 575                                 self.current_local_signed_commitment_tx = Some(local_tx);
 576                         }
 577                         self.payment_preimages = other.payment_preimages;
 578                 }
 579
 580                 self.current_remote_commitment_number = cmp::min(self.current_remote_commitment_number, other.current_remote_commitment_number);
 581                 Ok(())
 582         }
 583
 584         /// Panics if commitment_transaction_number_obscure_factor doesn't fit in 48 bits
 585         pub(super) fn set_commitment_obscure_factor(&mut self, commitment_transaction_number_obscure_factor: u64) {
 586                 assert!(commitment_transaction_number_obscure_factor < (1 << 48));
 587                 self.commitment_transaction_number_obscure_factor = commitment_transaction_number_obscure_factor;
 588         }
 589
 590         /// Allows this monitor to scan only for transactions which are applicable. Note that this is
 591         /// optional, without it this monitor cannot be used in an SPV client, but you may wish to
 592         /// avoid this (or call unset_funding_info) on a monitor you wish to send to a watchtower as it
 593         /// provides slightly better privacy.
 594         /// It's the responsibility of the caller to register outpoint and script with passing the former
 595         /// value as key to add_update_monitor.
 596         pub(super) fn set_funding_info(&mut self, funding_info: (OutPoint, Script)) {
 597                 self.funding_txo = Some(funding_info);
 598         }
 599
 600         /// We log these base keys at channel opening to being able to rebuild redeemscript in case of leaked revoked commit tx
 601         pub(super) fn set_their_base_keys(&mut self, their_htlc_base_key: &PublicKey, their_delayed_payment_base_key: &PublicKey) {
 602                 self.their_htlc_base_key = Some(their_htlc_base_key.clone());
 603                 self.their_delayed_payment_base_key = Some(their_delayed_payment_base_key.clone());
 604         }
 605
 606         pub(super) fn set_their_to_self_delay(&mut self, their_to_self_delay: u16) {
 607                 self.their_to_self_delay = Some(their_to_self_delay);
 608         }
 609
 610         pub(super) fn unset_funding_info(&mut self) {
 611                 self.funding_txo = None;
 612         }
 613
 614         /// Gets the funding transaction outpoint of the channel this ChannelMonitor is monitoring for.
 615         pub fn get_funding_txo(&self) -> Option<OutPoint> {
 616                 match self.funding_txo {
 617                         Some((outpoint, _)) => Some(outpoint),
 618                         None => None
 619                 }
 620         }
 621
 622         /// Gets the sets of all outpoints which this ChannelMonitor expects to hear about spends of.
 623         /// Generally useful when deserializing as during normal operation the return values of
 624         /// block_connected are sufficient to ensure all relevant outpoints are being monitored (note
 625         /// that the get_funding_txo outpoint and transaction must also be monitored for!).
 626         pub fn get_monitored_outpoints(&self) -> Vec<(Sha256dHash, u32, &Script)> {
 627                 let mut res = Vec::with_capacity(self.remote_commitment_txn_on_chain.len() * 2);
 628                 for (ref txid, &(_, ref outputs)) in self.remote_commitment_txn_on_chain.iter() {
 629                         for (idx, output) in outputs.iter().enumerate() {
 630                                 res.push(((*txid).clone(), idx as u32, output));
 631                         }
 632                 }
 633                 res
 634         }
 635
 636         /// Serializes into a vec, with various modes for the exposed pub fns
 637         fn write<W: Writer>(&self, writer: &mut W, for_local_storage: bool) -> Result<(), ::std::io::Error> {
 638                 //TODO: We still write out all the serialization here manually instead of using the fancy
 639                 //serialization framework we have, we should migrate things over to it.
 640                 writer.write_all(&[SERIALIZATION_VERSION; 1])?;
 641                 writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
 642
 643                 match &self.funding_txo {
 644                         &Some((ref outpoint, ref script)) => {
 645                                 writer.write_all(&outpoint.txid[..])?;
 646                                 writer.write_all(&byte_utils::be16_to_array(outpoint.index))?;
 647                                 script.write(writer)?;
 648                         },
 649                         &None => {
 650                                 // We haven't even been initialized...not sure why anyone is serializing us, but
 651                                 // not much to give them.
 652                                 return Ok(());
 653                         },
 654                 }
 655
 656                 // Set in initial Channel-object creation, so should always be set by now:
 657                 U48(self.commitment_transaction_number_obscure_factor).write(writer)?;
 658
 659                 match self.key_storage {
 660                         KeyStorage::PrivMode { ref revocation_base_key, ref htlc_base_key, ref delayed_payment_base_key, ref payment_base_key, ref shutdown_pubkey, ref prev_latest_per_commitment_point, ref latest_per_commitment_point } => {
 661                                 writer.write_all(&[0; 1])?;
 662                                 writer.write_all(&revocation_base_key[..])?;
 663                                 writer.write_all(&htlc_base_key[..])?;
 664                                 writer.write_all(&delayed_payment_base_key[..])?;
 665                                 writer.write_all(&payment_base_key[..])?;
 666                                 writer.write_all(&shutdown_pubkey.serialize())?;
 667                                 if let Some(ref prev_latest_per_commitment_point) = *prev_latest_per_commitment_point {
 668                                         writer.write_all(&[1; 1])?;
 669                                         writer.write_all(&prev_latest_per_commitment_point.serialize())?;
 670                                 } else {
 671                                         writer.write_all(&[0; 1])?;
 672                                 }
 673                                 if let Some(ref latest_per_commitment_point) = *latest_per_commitment_point {
 674                                         writer.write_all(&[1; 1])?;
 675                                         writer.write_all(&latest_per_commitment_point.serialize())?;
 676                                 } else {
 677                                         writer.write_all(&[0; 1])?;
 678                                 }
 679
 680                         },
 681                         KeyStorage::SigsMode { .. } => unimplemented!(),
 682                 }
 683
 684                 writer.write_all(&self.their_htlc_base_key.as_ref().unwrap().serialize())?;
 685                 writer.write_all(&self.their_delayed_payment_base_key.as_ref().unwrap().serialize())?;
 686
 687                 match self.their_cur_revocation_points {
 688                         Some((idx, pubkey, second_option)) => {
 689                                 writer.write_all(&byte_utils::be48_to_array(idx))?;
 690                                 writer.write_all(&pubkey.serialize())?;
 691                                 match second_option {
 692                                         Some(second_pubkey) => {
 693                                                 writer.write_all(&second_pubkey.serialize())?;
 694                                         },
 695                                         None => {
 696                                                 writer.write_all(&[0; 33])?;
 697                                         },
 698                                 }
 699                         },
 700                         None => {
 701                                 writer.write_all(&byte_utils::be48_to_array(0))?;
 702                         },
 703                 }
 704
 705                 writer.write_all(&byte_utils::be16_to_array(self.our_to_self_delay))?;
 706                 writer.write_all(&byte_utils::be16_to_array(self.their_to_self_delay.unwrap()))?;
 707
 708                 for &(ref secret, ref idx) in self.old_secrets.iter() {
 709                         writer.write_all(secret)?;
 710                         writer.write_all(&byte_utils::be64_to_array(*idx))?;
 711                 }
 712
 713                 macro_rules! serialize_htlc_in_commitment {
 714                         ($htlc_output: expr) => {
 715                                 writer.write_all(&[$htlc_output.offered as u8; 1])?;
 716                                 writer.write_all(&byte_utils::be64_to_array($htlc_output.amount_msat))?;
 717                                 writer.write_all(&byte_utils::be32_to_array($htlc_output.cltv_expiry))?;
 718                                 writer.write_all(&$htlc_output.payment_hash)?;
 719                                 writer.write_all(&byte_utils::be32_to_array($htlc_output.transaction_output_index))?;
 720                         }
 721                 }
 722
 723                 writer.write_all(&byte_utils::be64_to_array(self.remote_claimable_outpoints.len() as u64))?;
 724                 for (ref txid, ref htlc_outputs) in self.remote_claimable_outpoints.iter() {
 725                         writer.write_all(&txid[..])?;
 726                         writer.write_all(&byte_utils::be64_to_array(htlc_outputs.len() as u64))?;
 727                         for htlc_output in htlc_outputs.iter() {
 728                                 serialize_htlc_in_commitment!(htlc_output);
 729                         }
 730                 }
 731
 732                 writer.write_all(&byte_utils::be64_to_array(self.remote_commitment_txn_on_chain.len() as u64))?;
 733                 for (ref txid, &(commitment_number, ref txouts)) in self.remote_commitment_txn_on_chain.iter() {
 734                         writer.write_all(&txid[..])?;
 735                         writer.write_all(&byte_utils::be48_to_array(commitment_number))?;
 736                         (txouts.len() as u64).write(writer)?;
 737                         for script in txouts.iter() {
 738                                 script.write(writer)?;
 739                         }
 740                 }
 741
 742                 if for_local_storage {
 743                         writer.write_all(&byte_utils::be64_to_array(self.remote_hash_commitment_number.len() as u64))?;
 744                         for (ref payment_hash, commitment_number) in self.remote_hash_commitment_number.iter() {
 745                                 writer.write_all(*payment_hash)?;
 746                                 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
 747                         }
 748                 } else {
 749                         writer.write_all(&byte_utils::be64_to_array(0))?;
 750                 }
 751
 752                 macro_rules! serialize_local_tx {
 753                         ($local_tx: expr) => {
 754                                 if let Err(e) = $local_tx.tx.consensus_encode(&mut WriterWriteAdaptor(writer)) {
 755                                         match e {
 756                                                 encode::Error::Io(e) => return Err(e),
 757                                                 _ => panic!("local tx must have been well-formed!"),
 758                                         }
 759                                 }
 760
 761                                 writer.write_all(&$local_tx.revocation_key.serialize())?;
 762                                 writer.write_all(&$local_tx.a_htlc_key.serialize())?;
 763                                 writer.write_all(&$local_tx.b_htlc_key.serialize())?;
 764                                 writer.write_all(&$local_tx.delayed_payment_key.serialize())?;
 765
 766                                 writer.write_all(&byte_utils::be64_to_array($local_tx.feerate_per_kw))?;
 767                                 writer.write_all(&byte_utils::be64_to_array($local_tx.htlc_outputs.len() as u64))?;
 768                                 for &(ref htlc_output, ref their_sig, ref our_sig) in $local_tx.htlc_outputs.iter() {
 769                                         serialize_htlc_in_commitment!(htlc_output);
 770                                         writer.write_all(&their_sig.serialize_compact(&self.secp_ctx))?;
 771                                         writer.write_all(&our_sig.serialize_compact(&self.secp_ctx))?;
 772                                 }
 773                         }
 774                 }
 775
 776                 if let Some(ref prev_local_tx) = self.prev_local_signed_commitment_tx {
 777                         writer.write_all(&[1; 1])?;
 778                         serialize_local_tx!(prev_local_tx);
 779                 } else {
 780                         writer.write_all(&[0; 1])?;
 781                 }
 782
 783                 if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
 784                         writer.write_all(&[1; 1])?;
 785                         serialize_local_tx!(cur_local_tx);
 786                 } else {
 787                         writer.write_all(&[0; 1])?;
 788                 }
 789
 790                 if for_local_storage {
 791                         writer.write_all(&byte_utils::be48_to_array(self.current_remote_commitment_number))?;
 792                 } else {
 793                         writer.write_all(&byte_utils::be48_to_array(0))?;
 794                 }
 795
 796                 writer.write_all(&byte_utils::be64_to_array(self.payment_preimages.len() as u64))?;
 797                 for payment_preimage in self.payment_preimages.values() {
 798                         writer.write_all(payment_preimage)?;
 799                 }
 800
 801                 self.last_block_hash.write(writer)?;
 802                 self.destination_script.write(writer)?;
 803
 804                 Ok(())
 805         }
 806
 807         /// Writes this monitor into the given writer, suitable for writing to disk.
 808         ///
 809         /// Note that the deserializer is only implemented for (Sha256dHash, ChannelMonitor), which
 810         /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
 811         /// the "reorg path" (ie not just starting at the same height but starting at the highest
 812         /// common block that appears on your best chain as well as on the chain which contains the
 813         /// last block hash returned) upon deserializing the object!
 814         pub fn write_for_disk<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
 815                 self.write(writer, true)
 816         }
 817
 818         /// Encodes this monitor into the given writer, suitable for sending to a remote watchtower
 819         ///
 820         /// Note that the deserializer is only implemented for (Sha256dHash, ChannelMonitor), which
 821         /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
 822         /// the "reorg path" (ie not just starting at the same height but starting at the highest
 823         /// common block that appears on your best chain as well as on the chain which contains the
 824         /// last block hash returned) upon deserializing the object!
 825         pub fn write_for_watchtower<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
 826                 self.write(writer, false)
 827         }
 828
 829         //TODO: Functions to serialize/deserialize (with different forms depending on which information
 830         //we want to leave out (eg funding_txo, etc).
 831
 832         /// Can only fail if idx is < get_min_seen_secret
 833         pub(super) fn get_secret(&self, idx: u64) -> Result<[u8; 32], HandleError> {
 834                 for i in 0..self.old_secrets.len() {
 835                         if (idx & (!((1 << i) - 1))) == self.old_secrets[i].1 {
 836                                 return Ok(ChannelMonitor::derive_secret(self.old_secrets[i].0, i as u8, idx))
 837                         }
 838                 }
 839                 assert!(idx < self.get_min_seen_secret());
 840                 Err(HandleError{err: "idx too low", action: None})
 841         }
 842
 843         pub(super) fn get_min_seen_secret(&self) -> u64 {
 844                 //TODO This can be optimized?
 845                 let mut min = 1 << 48;
 846                 for &(_, idx) in self.old_secrets.iter() {
 847                         if idx < min {
 848                                 min = idx;
 849                         }
 850                 }
 851                 min
 852         }
 853
 854         pub(super) fn get_cur_remote_commitment_number(&self) -> u64 {
 855                 self.current_remote_commitment_number
 856         }
 857
 858         pub(super) fn get_cur_local_commitment_number(&self) -> u64 {
 859                 if let &Some(ref local_tx) = &self.current_local_signed_commitment_tx {
 860                         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)
 861                 } else { 0xffff_ffff_ffff }
 862         }
 863
 864         /// Attempts to claim a remote commitment transaction's outputs using the revocation key and
 865         /// data in remote_claimable_outpoints. Will directly claim any HTLC outputs which expire at a
 866         /// height > height + CLTV_SHARED_CLAIM_BUFFER. In any case, will install monitoring for
 867         /// HTLC-Success/HTLC-Timeout transactions.
 868         fn check_spend_remote_transaction(&mut self, tx: &Transaction, height: u32) -> (Vec<Transaction>, (Sha256dHash, Vec<TxOut>), Vec<SpendableOutputDescriptor>) {
 869                 // Most secp and related errors trying to create keys means we have no hope of constructing
 870                 // a spend transaction...so we return no transactions to broadcast
 871                 let mut txn_to_broadcast = Vec::new();
 872                 let mut watch_outputs = Vec::new();
 873                 let mut spendable_outputs = Vec::new();
 874
 875                 let commitment_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
 876                 let per_commitment_option = self.remote_claimable_outpoints.get(&commitment_txid);
 877
 878                 macro_rules! ignore_error {
 879                         ( $thing : expr ) => {
 880                                 match $thing {
 881                                         Ok(a) => a,
 882                                         Err(_) => return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs)
 883                                 }
 884                         };
 885                 }
 886
 887                 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);
 888                 if commitment_number >= self.get_min_seen_secret() {
 889                         let secret = self.get_secret(commitment_number).unwrap();
 890                         let per_commitment_key = ignore_error!(SecretKey::from_slice(&self.secp_ctx, &secret));
 891                         let (revocation_pubkey, b_htlc_key) = match self.key_storage {
 892                                 KeyStorage::PrivMode { ref revocation_base_key, ref htlc_base_key, .. } => {
 893                                         let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
 894                                         (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &PublicKey::from_secret_key(&self.secp_ctx, &revocation_base_key))),
 895                                         ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &PublicKey::from_secret_key(&self.secp_ctx, &htlc_base_key))))
 896                                 },
 897                                 KeyStorage::SigsMode { ref revocation_base_key, ref htlc_base_key, .. } => {
 898                                         let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
 899                                         (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &revocation_base_key)),
 900                                         ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &htlc_base_key)))
 901                                 },
 902                         };
 903                         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()));
 904                         let a_htlc_key = match self.their_htlc_base_key {
 905                                 None => return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs),
 906                                 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)),
 907                         };
 908
 909                         let revokeable_redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.our_to_self_delay, &delayed_key);
 910                         let revokeable_p2wsh = revokeable_redeemscript.to_v0_p2wsh();
 911
 912                         let mut total_value = 0;
 913                         let mut values = Vec::new();
 914                         let mut inputs = Vec::new();
 915                         let mut htlc_idxs = Vec::new();
 916
 917                         for (idx, outp) in tx.output.iter().enumerate() {
 918                                 if outp.script_pubkey == revokeable_p2wsh {
 919                                         inputs.push(TxIn {
 920                                                 previous_output: BitcoinOutPoint {
 921                                                         txid: commitment_txid,
 922                                                         vout: idx as u32,
 923                                                 },
 924                                                 script_sig: Script::new(),
 925                                                 sequence: 0xfffffffd,
 926                                                 witness: Vec::new(),
 927                                         });
 928                                         htlc_idxs.push(None);
 929                                         values.push(outp.value);
 930                                         total_value += outp.value;
 931                                 } else if outp.script_pubkey.is_v0_p2wpkh() {
 932                                         match self.key_storage {
 933                                                 KeyStorage::PrivMode { ref payment_base_key, .. } => {
 934                                                         let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
 935                                                         if let Ok(local_key) = chan_utils::derive_private_key(&self.secp_ctx, &per_commitment_point, &payment_base_key) {
 936                                                                 spendable_outputs.push(SpendableOutputDescriptor::DynamicOutputP2WPKH {
 937                                                                         outpoint: BitcoinOutPoint { txid: commitment_txid, vout: idx as u32 },
 938                                                                         key: local_key,
 939                                                                         output: outp.clone(),
 940                                                                 });
 941                                                         }
 942                                                 }
 943                                                 KeyStorage::SigsMode { .. } => {
 944                                                         //TODO: we need to ensure an offline client will generate the event when it
 945                                                         // cames back online after only the watchtower saw the transaction
 946                                                 }
 947                                         }
 948                                 }
 949                         }
 950
 951                         macro_rules! sign_input {
 952                                 ($sighash_parts: expr, $input: expr, $htlc_idx: expr, $amount: expr) => {
 953                                         {
 954                                                 let (sig, redeemscript) = match self.key_storage {
 955                                                         KeyStorage::PrivMode { ref revocation_base_key, .. } => {
 956                                                                 let redeemscript = if $htlc_idx.is_none() { revokeable_redeemscript.clone() } else {
 957                                                                         let htlc = &per_commitment_option.unwrap()[$htlc_idx.unwrap()];
 958                                                                         chan_utils::get_htlc_redeemscript_with_explicit_keys(htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey)
 959                                                                 };
 960                                                                 let sighash = ignore_error!(Message::from_slice(&$sighash_parts.sighash_all(&$input, &redeemscript, $amount)[..]));
 961                                                                 let revocation_key = ignore_error!(chan_utils::derive_private_revocation_key(&self.secp_ctx, &per_commitment_key, &revocation_base_key));
 962                                                                 (self.secp_ctx.sign(&sighash, &revocation_key), redeemscript)
 963                                                         },
 964                                                         KeyStorage::SigsMode { .. } => {
 965                                                                 unimplemented!();
 966                                                         }
 967                                                 };
 968                                                 $input.witness.push(sig.serialize_der(&self.secp_ctx).to_vec());
 969                                                 $input.witness[0].push(SigHashType::All as u8);
 970                                                 if $htlc_idx.is_none() {
 971                                                         $input.witness.push(vec!(1));
 972                                                 } else {
 973                                                         $input.witness.push(revocation_pubkey.serialize().to_vec());
 974                                                 }
 975                                                 $input.witness.push(redeemscript.into_bytes());
 976                                         }
 977                                 }
 978                         }
 979
 980                         if let Some(per_commitment_data) = per_commitment_option {
 981                                 inputs.reserve_exact(per_commitment_data.len());
 982
 983                                 for (idx, htlc) in per_commitment_data.iter().enumerate() {
 984                                         let expected_script = chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey);
 985                                         if htlc.transaction_output_index as usize >= tx.output.len() ||
 986                                                         tx.output[htlc.transaction_output_index as usize].value != htlc.amount_msat / 1000 ||
 987                                                         tx.output[htlc.transaction_output_index as usize].script_pubkey != expected_script.to_v0_p2wsh() {
 988                                                 return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs); // Corrupted per_commitment_data, fuck this user
 989                                         }
 990                                         let input = TxIn {
 991                                                 previous_output: BitcoinOutPoint {
 992                                                         txid: commitment_txid,
 993                                                         vout: htlc.transaction_output_index,
 994                                                 },
 995                                                 script_sig: Script::new(),
 996                                                 sequence: 0xfffffffd,
 997                                                 witness: Vec::new(),
 998                                         };
 999                                         if htlc.cltv_expiry > height + CLTV_SHARED_CLAIM_BUFFER {
1000                                                 inputs.push(input);
1001                                                 htlc_idxs.push(Some(idx));
1002                                                 values.push(tx.output[htlc.transaction_output_index as usize].value);
1003                                                 total_value += htlc.amount_msat / 1000;
1004                                         } else {
1005                                                 let mut single_htlc_tx = Transaction {
1006                                                         version: 2,
1007                                                         lock_time: 0,
1008                                                         input: vec![input],
1009                                                         output: vec!(TxOut {
1010                                                                 script_pubkey: self.destination_script.clone(),
1011                                                                 value: htlc.amount_msat / 1000, //TODO: - fee
1012                                                         }),
1013                                                 };
1014                                                 let sighash_parts = bip143::SighashComponents::new(&single_htlc_tx);
1015                                                 sign_input!(sighash_parts, single_htlc_tx.input[0], Some(idx), htlc.amount_msat / 1000);
1016                                                 txn_to_broadcast.push(single_htlc_tx);
1017                                         }
1018                                 }
1019                         }
1020
1021                         if !inputs.is_empty() || !txn_to_broadcast.is_empty() { // ie we're confident this is actually ours
1022                                 // We're definitely a remote commitment transaction!
1023                                 watch_outputs.append(&mut tx.output.clone());
1024                                 self.remote_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
1025                         }
1026                         if inputs.is_empty() { return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs); } // Nothing to be done...probably a false positive/local tx
1027
1028                         let outputs = vec!(TxOut {
1029                                 script_pubkey: self.destination_script.clone(),
1030                                 value: total_value, //TODO: - fee
1031                         });
1032                         let mut spend_tx = Transaction {
1033                                 version: 2,
1034                                 lock_time: 0,
1035                                 input: inputs,
1036                                 output: outputs,
1037                         };
1038
1039                         let mut values_drain = values.drain(..);
1040                         let sighash_parts = bip143::SighashComponents::new(&spend_tx);
1041
1042                         for (input, htlc_idx) in spend_tx.input.iter_mut().zip(htlc_idxs.iter()) {
1043                                 let value = values_drain.next().unwrap();
1044                                 sign_input!(sighash_parts, input, htlc_idx, value);
1045                         }
1046
1047                         spendable_outputs.push(SpendableOutputDescriptor::StaticOutput {
1048                                 outpoint: BitcoinOutPoint { txid: spend_tx.txid(), vout: 0 },
1049                                 output: spend_tx.output[0].clone(),
1050                         });
1051                         txn_to_broadcast.push(spend_tx);
1052                 } else if let Some(per_commitment_data) = per_commitment_option {
1053                         // While this isn't useful yet, there is a potential race where if a counterparty
1054                         // revokes a state at the same time as the commitment transaction for that state is
1055                         // confirmed, and the watchtower receives the block before the user, the user could
1056                         // upload a new ChannelMonitor with the revocation secret but the watchtower has
1057                         // already processed the block, resulting in the remote_commitment_txn_on_chain entry
1058                         // not being generated by the above conditional. Thus, to be safe, we go ahead and
1059                         // insert it here.
1060                         watch_outputs.append(&mut tx.output.clone());
1061                         self.remote_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
1062
1063                         if let Some(revocation_points) = self.their_cur_revocation_points {
1064                                 let revocation_point_option =
1065                                         if revocation_points.0 == commitment_number { Some(&revocation_points.1) }
1066                                         else if let Some(point) = revocation_points.2.as_ref() {
1067                                                 if revocation_points.0 == commitment_number + 1 { Some(point) } else { None }
1068                                         } else { None };
1069                                 if let Some(revocation_point) = revocation_point_option {
1070                                         let (revocation_pubkey, b_htlc_key) = match self.key_storage {
1071                                                 KeyStorage::PrivMode { ref revocation_base_key, ref htlc_base_key, .. } => {
1072                                                         (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, revocation_point, &PublicKey::from_secret_key(&self.secp_ctx, &revocation_base_key))),
1073                                                         ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &PublicKey::from_secret_key(&self.secp_ctx, &htlc_base_key))))
1074                                                 },
1075                                                 KeyStorage::SigsMode { ref revocation_base_key, ref htlc_base_key, .. } => {
1076                                                         (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, revocation_point, &revocation_base_key)),
1077                                                         ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &htlc_base_key)))
1078                                                 },
1079                                         };
1080                                         let a_htlc_key = match self.their_htlc_base_key {
1081                                                 None => return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs),
1082                                                 Some(their_htlc_base_key) => ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &their_htlc_base_key)),
1083                                         };
1084
1085
1086                                         for (idx, outp) in tx.output.iter().enumerate() {
1087                                                 if outp.script_pubkey.is_v0_p2wpkh() {
1088                                                         match self.key_storage {
1089                                                                 KeyStorage::PrivMode { ref payment_base_key, .. } => {
1090                                                                         if let Ok(local_key) = chan_utils::derive_private_key(&self.secp_ctx, &revocation_point, &payment_base_key) {
1091                                                                                 spendable_outputs.push(SpendableOutputDescriptor::DynamicOutputP2WPKH {
1092                                                                                         outpoint: BitcoinOutPoint { txid: commitment_txid, vout: idx as u32 },
1093                                                                                         key: local_key,
1094                                                                                         output: outp.clone(),
1095                                                                                 });
1096                                                                         }
1097                                                                 }
1098                                                                 KeyStorage::SigsMode { .. } => {
1099                                                                         //TODO: we need to ensure an offline client will generate the event when it
1100                                                                         // cames back online after only the watchtower saw the transaction
1101                                                                 }
1102                                                         }
1103                                                         break; // Only to_remote ouput is claimable
1104                                                 }
1105                                         }
1106
1107                                         let mut total_value = 0;
1108                                         let mut values = Vec::new();
1109                                         let mut inputs = Vec::new();
1110
1111                                         macro_rules! sign_input {
1112                                                 ($sighash_parts: expr, $input: expr, $amount: expr, $preimage: expr) => {
1113                                                         {
1114                                                                 let (sig, redeemscript) = match self.key_storage {
1115                                                                         KeyStorage::PrivMode { ref htlc_base_key, .. } => {
1116                                                                                 let htlc = &per_commitment_option.unwrap()[$input.sequence as usize];
1117                                                                                 let redeemscript = chan_utils::get_htlc_redeemscript_with_explicit_keys(htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey);
1118                                                                                 let sighash = ignore_error!(Message::from_slice(&$sighash_parts.sighash_all(&$input, &redeemscript, $amount)[..]));
1119                                                                                 let htlc_key = ignore_error!(chan_utils::derive_private_key(&self.secp_ctx, revocation_point, &htlc_base_key));
1120                                                                                 (self.secp_ctx.sign(&sighash, &htlc_key), redeemscript)
1121                                                                         },
1122                                                                         KeyStorage::SigsMode { .. } => {
1123                                                                                 unimplemented!();
1124                                                                         }
1125                                                                 };
1126                                                                 $input.witness.push(sig.serialize_der(&self.secp_ctx).to_vec());
1127                                                                 $input.witness[0].push(SigHashType::All as u8);
1128                                                                 $input.witness.push($preimage);
1129                                                                 $input.witness.push(redeemscript.into_bytes());
1130                                                         }
1131                                                 }
1132                                         }
1133
1134                                         for (idx, htlc) in per_commitment_data.iter().enumerate() {
1135                                                 if let Some(payment_preimage) = self.payment_preimages.get(&htlc.payment_hash) {
1136                                                         let input = TxIn {
1137                                                                 previous_output: BitcoinOutPoint {
1138                                                                         txid: commitment_txid,
1139                                                                         vout: htlc.transaction_output_index,
1140                                                                 },
1141                                                                 script_sig: Script::new(),
1142                                                                 sequence: idx as u32, // reset to 0xfffffffd in sign_input
1143                                                                 witness: Vec::new(),
1144                                                         };
1145                                                         if htlc.cltv_expiry > height + CLTV_SHARED_CLAIM_BUFFER {
1146                                                                 inputs.push(input);
1147                                                                 values.push((tx.output[htlc.transaction_output_index as usize].value, payment_preimage));
1148                                                                 total_value += htlc.amount_msat / 1000;
1149                                                         } else {
1150                                                                 let mut single_htlc_tx = Transaction {
1151                                                                         version: 2,
1152                                                                         lock_time: 0,
1153                                                                         input: vec![input],
1154                                                                         output: vec!(TxOut {
1155                                                                                 script_pubkey: self.destination_script.clone(),
1156                                                                                 value: htlc.amount_msat / 1000, //TODO: - fee
1157                                                                         }),
1158                                                                 };
1159                                                                 let sighash_parts = bip143::SighashComponents::new(&single_htlc_tx);
1160                                                                 sign_input!(sighash_parts, single_htlc_tx.input[0], htlc.amount_msat / 1000, payment_preimage.to_vec());
1161                                                                 spendable_outputs.push(SpendableOutputDescriptor::StaticOutput {
1162                                                                         outpoint: BitcoinOutPoint { txid: single_htlc_tx.txid(), vout: 0 },
1163                                                                         output: single_htlc_tx.output[0].clone(),
1164                                                                 });
1165                                                                 txn_to_broadcast.push(single_htlc_tx);
1166                                                         }
1167                                                 }
1168                                         }
1169
1170                                         if inputs.is_empty() { return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs); } // Nothing to be done...probably a false positive/local tx
1171
1172                                         let outputs = vec!(TxOut {
1173                                                 script_pubkey: self.destination_script.clone(),
1174                                                 value: total_value, //TODO: - fee
1175                                         });
1176                                         let mut spend_tx = Transaction {
1177                                                 version: 2,
1178                                                 lock_time: 0,
1179                                                 input: inputs,
1180                                                 output: outputs,
1181                                         };
1182
1183                                         let mut values_drain = values.drain(..);
1184                                         let sighash_parts = bip143::SighashComponents::new(&spend_tx);
1185
1186                                         for input in spend_tx.input.iter_mut() {
1187                                                 let value = values_drain.next().unwrap();
1188                                                 sign_input!(sighash_parts, input, value.0, value.1.to_vec());
1189                                         }
1190
1191                                         spendable_outputs.push(SpendableOutputDescriptor::StaticOutput {
1192                                                 outpoint: BitcoinOutPoint { txid: spend_tx.txid(), vout: 0 },
1193                                                 output: spend_tx.output[0].clone(),
1194                                         });
1195                                         txn_to_broadcast.push(spend_tx);
1196                                 }
1197                         }
1198                 }
1199
1200                 (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs)
1201         }
1202
1203         /// Attempst to claim a remote HTLC-Success/HTLC-Timeout s outputs using the revocation key
1204         fn check_spend_remote_htlc(&self, tx: &Transaction, commitment_number: u64) -> (Option<Transaction>, Option<SpendableOutputDescriptor>) {
1205                 if tx.input.len() != 1 || tx.output.len() != 1 {
1206                         return (None, None)
1207                 }
1208
1209                 macro_rules! ignore_error {
1210                         ( $thing : expr ) => {
1211                                 match $thing {
1212                                         Ok(a) => a,
1213                                         Err(_) => return (None, None)
1214                                 }
1215                         };
1216                 }
1217
1218                 let secret = ignore_error!(self.get_secret(commitment_number));
1219                 let per_commitment_key = ignore_error!(SecretKey::from_slice(&self.secp_ctx, &secret));
1220                 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1221                 let revocation_pubkey = match self.key_storage {
1222                         KeyStorage::PrivMode { ref revocation_base_key, .. } => {
1223                                 ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &PublicKey::from_secret_key(&self.secp_ctx, &revocation_base_key)))
1224                         },
1225                         KeyStorage::SigsMode { ref revocation_base_key, .. } => {
1226                                 ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &revocation_base_key))
1227                         },
1228                 };
1229                 let delayed_key = match self.their_delayed_payment_base_key {
1230                         None => return (None, None),
1231                         Some(their_delayed_payment_base_key) => ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &their_delayed_payment_base_key)),
1232                 };
1233                 let redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.their_to_self_delay.unwrap(), &delayed_key);
1234                 let revokeable_p2wsh = redeemscript.to_v0_p2wsh();
1235                 let htlc_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
1236
1237                 let mut inputs = Vec::new();
1238                 let mut amount = 0;
1239
1240                 if tx.output[0].script_pubkey == revokeable_p2wsh { //HTLC transactions have one txin, one txout
1241                         inputs.push(TxIn {
1242                                 previous_output: BitcoinOutPoint {
1243                                         txid: htlc_txid,
1244                                         vout: 0,
1245                                 },
1246                                 script_sig: Script::new(),
1247                                 sequence: 0xfffffffd,
1248                                 witness: Vec::new(),
1249                         });
1250                         amount = tx.output[0].value;
1251                 }
1252
1253                 if !inputs.is_empty() {
1254                         let outputs = vec!(TxOut {
1255                                 script_pubkey: self.destination_script.clone(),
1256                                 value: amount, //TODO: - fee
1257                         });
1258
1259                         let mut spend_tx = Transaction {
1260                                 version: 2,
1261                                 lock_time: 0,
1262                                 input: inputs,
1263                                 output: outputs,
1264                         };
1265
1266                         let sighash_parts = bip143::SighashComponents::new(&spend_tx);
1267
1268                         let sig = match self.key_storage {
1269                                 KeyStorage::PrivMode { ref revocation_base_key, .. } => {
1270                                         let sighash = ignore_error!(Message::from_slice(&sighash_parts.sighash_all(&spend_tx.input[0], &redeemscript, amount)[..]));
1271                                         let revocation_key = ignore_error!(chan_utils::derive_private_revocation_key(&self.secp_ctx, &per_commitment_key, &revocation_base_key));
1272                                         self.secp_ctx.sign(&sighash, &revocation_key)
1273                                 }
1274                                 KeyStorage::SigsMode { .. } => {
1275                                         unimplemented!();
1276                                 }
1277                         };
1278                         spend_tx.input[0].witness.push(sig.serialize_der(&self.secp_ctx).to_vec());
1279                         spend_tx.input[0].witness[0].push(SigHashType::All as u8);
1280                         spend_tx.input[0].witness.push(vec!(1));
1281                         spend_tx.input[0].witness.push(redeemscript.into_bytes());
1282
1283                         let outpoint = BitcoinOutPoint { txid: spend_tx.txid(), vout: 0 };
1284                         let output = spend_tx.output[0].clone();
1285                         (Some(spend_tx), Some(SpendableOutputDescriptor::StaticOutput { outpoint, output }))
1286                 } else { (None, None) }
1287         }
1288
1289         fn broadcast_by_local_state(&self, local_tx: &LocalSignedTx, per_commitment_point: &Option<PublicKey>, delayed_payment_base_key: &Option<SecretKey>) -> (Vec<Transaction>, Vec<SpendableOutputDescriptor>) {
1290                 let mut res = Vec::with_capacity(local_tx.htlc_outputs.len());
1291                 let mut spendable_outputs = Vec::with_capacity(local_tx.htlc_outputs.len());
1292
1293                 macro_rules! add_dynamic_output {
1294                         ($father_tx: expr, $vout: expr) => {
1295                                 if let Some(ref per_commitment_point) = *per_commitment_point {
1296                                         if let Some(ref delayed_payment_base_key) = *delayed_payment_base_key {
1297                                                 if let Ok(local_delayedkey) = chan_utils::derive_private_key(&self.secp_ctx, per_commitment_point, delayed_payment_base_key) {
1298                                                         spendable_outputs.push(SpendableOutputDescriptor::DynamicOutputP2WSH {
1299                                                                 outpoint: BitcoinOutPoint { txid: $father_tx.txid(), vout: $vout },
1300                                                                 key: local_delayedkey,
1301                                                                 witness_script: chan_utils::get_revokeable_redeemscript(&local_tx.revocation_key, self.our_to_self_delay, &local_tx.delayed_payment_key),
1302                                                                 to_self_delay: self.our_to_self_delay,
1303                                                                 output: $father_tx.output[$vout as usize].clone(),
1304                                                         });
1305                                                 }
1306                                         }
1307                                 }
1308                         }
1309                 }
1310
1311
1312                 let redeemscript = chan_utils::get_revokeable_redeemscript(&local_tx.revocation_key, self.their_to_self_delay.unwrap(), &local_tx.delayed_payment_key);
1313                 let revokeable_p2wsh = redeemscript.to_v0_p2wsh();
1314                 for (idx, output) in local_tx.tx.output.iter().enumerate() {
1315                         if output.script_pubkey == revokeable_p2wsh {
1316                                 add_dynamic_output!(local_tx.tx, idx as u32);
1317                                 break;
1318                         }
1319                 }
1320
1321                 for &(ref htlc, ref their_sig, ref our_sig) in local_tx.htlc_outputs.iter() {
1322                         if htlc.offered {
1323                                 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);
1324
1325                                 htlc_timeout_tx.input[0].witness.push(Vec::new()); // First is the multisig dummy
1326
1327                                 htlc_timeout_tx.input[0].witness.push(their_sig.serialize_der(&self.secp_ctx).to_vec());
1328                                 htlc_timeout_tx.input[0].witness[1].push(SigHashType::All as u8);
1329                                 htlc_timeout_tx.input[0].witness.push(our_sig.serialize_der(&self.secp_ctx).to_vec());
1330                                 htlc_timeout_tx.input[0].witness[2].push(SigHashType::All as u8);
1331
1332                                 htlc_timeout_tx.input[0].witness.push(Vec::new());
1333                                 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());
1334
1335                                 add_dynamic_output!(htlc_timeout_tx, 0);
1336                                 res.push(htlc_timeout_tx);
1337                         } else {
1338                                 if let Some(payment_preimage) = self.payment_preimages.get(&htlc.payment_hash) {
1339                                         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);
1340
1341                                         htlc_success_tx.input[0].witness.push(Vec::new()); // First is the multisig dummy
1342
1343                                         htlc_success_tx.input[0].witness.push(their_sig.serialize_der(&self.secp_ctx).to_vec());
1344                                         htlc_success_tx.input[0].witness[1].push(SigHashType::All as u8);
1345                                         htlc_success_tx.input[0].witness.push(our_sig.serialize_der(&self.secp_ctx).to_vec());
1346                                         htlc_success_tx.input[0].witness[2].push(SigHashType::All as u8);
1347
1348                                         htlc_success_tx.input[0].witness.push(payment_preimage.to_vec());
1349                                         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());
1350
1351                                         add_dynamic_output!(htlc_success_tx, 0);
1352                                         res.push(htlc_success_tx);
1353                                 }
1354                         }
1355                 }
1356
1357                 (res, spendable_outputs)
1358         }
1359
1360         /// Attempts to claim any claimable HTLCs in a commitment transaction which was not (yet)
1361         /// revoked using data in local_claimable_outpoints.
1362         /// Should not be used if check_spend_revoked_transaction succeeds.
1363         fn check_spend_local_transaction(&self, tx: &Transaction, _height: u32) -> (Vec<Transaction>, Vec<SpendableOutputDescriptor>) {
1364                 let commitment_txid = tx.txid();
1365                 if let &Some(ref local_tx) = &self.current_local_signed_commitment_tx {
1366                         if local_tx.txid == commitment_txid {
1367                                 match self.key_storage {
1368                                         KeyStorage::PrivMode { ref delayed_payment_base_key, ref latest_per_commitment_point, .. } => {
1369                                                 return self.broadcast_by_local_state(local_tx, latest_per_commitment_point, &Some(*delayed_payment_base_key));
1370                                         },
1371                                         KeyStorage::SigsMode { .. } => {
1372                                                 return self.broadcast_by_local_state(local_tx, &None, &None);
1373                                         }
1374                                 }
1375                         }
1376                 }
1377                 if let &Some(ref local_tx) = &self.prev_local_signed_commitment_tx {
1378                         if local_tx.txid == commitment_txid {
1379                                 match self.key_storage {
1380                                         KeyStorage::PrivMode { ref delayed_payment_base_key, ref prev_latest_per_commitment_point, .. } => {
1381                                                 return self.broadcast_by_local_state(local_tx, prev_latest_per_commitment_point, &Some(*delayed_payment_base_key));
1382                                         },
1383                                         KeyStorage::SigsMode { .. } => {
1384                                                 return self.broadcast_by_local_state(local_tx, &None, &None);
1385                                         }
1386                                 }
1387                         }
1388                 }
1389                 (Vec::new(), Vec::new())
1390         }
1391
1392         /// Generate a spendable output event when closing_transaction get registered onchain.
1393         fn check_spend_closing_transaction(&self, tx: &Transaction) -> Option<SpendableOutputDescriptor> {
1394                 if tx.input[0].sequence == 0xFFFFFFFF && tx.input[0].witness.last().unwrap().len() == 71 {
1395                         match self.key_storage {
1396                                 KeyStorage::PrivMode { ref shutdown_pubkey, .. } =>  {
1397                                         let our_channel_close_key_hash = Hash160::from_data(&shutdown_pubkey.serialize());
1398                                         let shutdown_script = Builder::new().push_opcode(opcodes::All::OP_PUSHBYTES_0).push_slice(&our_channel_close_key_hash[..]).into_script();
1399                                         for (idx, output) in tx.output.iter().enumerate() {
1400                                                 if shutdown_script == output.script_pubkey {
1401                                                         return Some(SpendableOutputDescriptor::StaticOutput {
1402                                                                 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: idx as u32 },
1403                                                                 output: output.clone(),
1404                                                         });
1405                                                 }
1406                                         }
1407                                 }
1408                                 KeyStorage::SigsMode { .. } => {
1409                                         //TODO: we need to ensure an offline client will generate the event when it
1410                                         // cames back online after only the watchtower saw the transaction
1411                                 }
1412                         }
1413                 }
1414                 None
1415         }
1416
1417         /// Used by ChannelManager deserialization to broadcast the latest local state if it's copy of
1418         /// the Channel was out-of-date.
1419         pub(super) fn get_latest_local_commitment_txn(&self) -> Vec<Transaction> {
1420                 if let &Some(ref local_tx) = &self.current_local_signed_commitment_tx {
1421                         let mut res = vec![local_tx.tx.clone()];
1422                         match self.key_storage {
1423                                 KeyStorage::PrivMode { ref delayed_payment_base_key, ref prev_latest_per_commitment_point, .. } => {
1424                                         res.append(&mut self.broadcast_by_local_state(local_tx, prev_latest_per_commitment_point, &Some(*delayed_payment_base_key)).0);
1425                                 },
1426                                 _ => panic!("Can only broadcast by local channelmonitor"),
1427                         };
1428                         res
1429                 } else {
1430                         Vec::new()
1431                 }
1432         }
1433
1434         fn block_connected(&mut self, txn_matched: &[&Transaction], height: u32, block_hash: &Sha256dHash, broadcaster: &BroadcasterInterface)-> (Vec<(Sha256dHash, Vec<TxOut>)>, Vec<SpendableOutputDescriptor>) {
1435                 let mut watch_outputs = Vec::new();
1436                 let mut spendable_outputs = Vec::new();
1437                 for tx in txn_matched {
1438                         if tx.input.len() == 1 {
1439                                 // Assuming our keys were not leaked (in which case we're screwed no matter what),
1440                                 // commitment transactions and HTLC transactions will all only ever have one input,
1441                                 // which is an easy way to filter out any potential non-matching txn for lazy
1442                                 // filters.
1443                                 let prevout = &tx.input[0].previous_output;
1444                                 let mut txn: Vec<Transaction> = Vec::new();
1445                                 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) {
1446                                         let (remote_txn, new_outputs, mut spendable_output) = self.check_spend_remote_transaction(tx, height);
1447                                         txn = remote_txn;
1448                                         spendable_outputs.append(&mut spendable_output);
1449                                         if !new_outputs.1.is_empty() {
1450                                                 watch_outputs.push(new_outputs);
1451                                         }
1452                                         if txn.is_empty() {
1453                                                 let (remote_txn, mut outputs) = self.check_spend_local_transaction(tx, height);
1454                                                 spendable_outputs.append(&mut outputs);
1455                                                 txn = remote_txn;
1456                                         }
1457                                         if !self.funding_txo.is_none() && txn.is_empty() {
1458                                                 if let Some(spendable_output) = self.check_spend_closing_transaction(tx) {
1459                                                         spendable_outputs.push(spendable_output);
1460                                                 }
1461                                         }
1462                                 } else {
1463                                         if let Some(&(commitment_number, _)) = self.remote_commitment_txn_on_chain.get(&prevout.txid) {
1464                                                 let (tx, spendable_output) = self.check_spend_remote_htlc(tx, commitment_number);
1465                                                 if let Some(tx) = tx {
1466                                                         txn.push(tx);
1467                                                 }
1468                                                 if let Some(spendable_output) = spendable_output {
1469                                                         spendable_outputs.push(spendable_output);
1470                                                 }
1471                                         }
1472                                 }
1473                                 for tx in txn.iter() {
1474                                         broadcaster.broadcast_transaction(tx);
1475                                 }
1476                         }
1477                 }
1478                 if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
1479                         if self.would_broadcast_at_height(height) {
1480                                 broadcaster.broadcast_transaction(&cur_local_tx.tx);
1481                                 match self.key_storage {
1482                                         KeyStorage::PrivMode { ref delayed_payment_base_key, ref latest_per_commitment_point, .. } => {
1483                                                 let (txs, mut outputs) = self.broadcast_by_local_state(&cur_local_tx, latest_per_commitment_point, &Some(*delayed_payment_base_key));
1484                                                 spendable_outputs.append(&mut outputs);
1485                                                 for tx in txs {
1486                                                         broadcaster.broadcast_transaction(&tx);
1487                                                 }
1488                                         },
1489                                         KeyStorage::SigsMode { .. } => {
1490                                                 let (txs, mut outputs) = self.broadcast_by_local_state(&cur_local_tx, &None, &None);
1491                                                 spendable_outputs.append(&mut outputs);
1492                                                 for tx in txs {
1493                                                         broadcaster.broadcast_transaction(&tx);
1494                                                 }
1495                                         }
1496                                 }
1497                         }
1498                 }
1499                 self.last_block_hash = block_hash.clone();
1500                 (watch_outputs, spendable_outputs)
1501         }
1502
1503         pub(super) fn would_broadcast_at_height(&self, height: u32) -> bool {
1504                 if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
1505                         for &(ref htlc, _, _) in cur_local_tx.htlc_outputs.iter() {
1506                                 // For inbound HTLCs which we know the preimage for, we have to ensure we hit the
1507                                 // chain with enough room to claim the HTLC without our counterparty being able to
1508                                 // time out the HTLC first.
1509                                 // For outbound HTLCs which our counterparty hasn't failed/claimed, our primary
1510                                 // concern is being able to claim the corresponding inbound HTLC (on another
1511                                 // channel) before it expires. In fact, we don't even really care if our
1512                                 // counterparty here claims such an outbound HTLC after it expired as long as we
1513                                 // can still claim the corresponding HTLC. Thus, to avoid needlessly hitting the
1514                                 // chain when our counterparty is waiting for expiration to off-chain fail an HTLC
1515                                 // we give ourselves a few blocks of headroom after expiration before going
1516                                 // on-chain for an expired HTLC.
1517                                 // Note that, to avoid a potential attack whereby a node delays claiming an HTLC
1518                                 // from us until we've reached the point where we go on-chain with the
1519                                 // corresponding inbound HTLC, we must ensure that outbound HTLCs go on chain at
1520                                 // least CLTV_CLAIM_BUFFER blocks prior to the inbound HTLC.
1521                                 //  aka outbound_cltv + HTLC_FAIL_TIMEOUT_BLOCKS == height - CLTV_CLAIM_BUFFER
1522                                 //      inbound_cltv == height + CLTV_CLAIM_BUFFER
1523                                 //      outbound_cltv + HTLC_FAIL_TIMEOUT_BLOCKS + CLTV_CLAIM_BUFER <= inbound_cltv - CLTV_CLAIM_BUFFER
1524                                 //      HTLC_FAIL_TIMEOUT_BLOCKS + 2*CLTV_CLAIM_BUFER <= inbound_cltv - outbound_cltv
1525                                 //      HTLC_FAIL_TIMEOUT_BLOCKS + 2*CLTV_CLAIM_BUFER <= CLTV_EXPIRY_DELTA
1526                                 if ( htlc.offered && htlc.cltv_expiry + HTLC_FAIL_TIMEOUT_BLOCKS <= height) ||
1527                                    (!htlc.offered && htlc.cltv_expiry <= height + CLTV_CLAIM_BUFFER && self.payment_preimages.contains_key(&htlc.payment_hash)) {
1528                                         return true;
1529                                 }
1530                         }
1531                 }
1532                 false
1533         }
1534 }
1535
1536 const MAX_ALLOC_SIZE: usize = 64*1024;
1537
1538 impl<R: ::std::io::Read> ReadableArgs<R, Arc<Logger>> for (Sha256dHash, ChannelMonitor) {
1539         fn read(reader: &mut R, logger: Arc<Logger>) -> Result<Self, DecodeError> {
1540                 let secp_ctx = Secp256k1::new();
1541                 macro_rules! unwrap_obj {
1542                         ($key: expr) => {
1543                                 match $key {
1544                                         Ok(res) => res,
1545                                         Err(_) => return Err(DecodeError::InvalidValue),
1546                                 }
1547                         }
1548                 }
1549
1550                 let _ver: u8 = Readable::read(reader)?;
1551                 let min_ver: u8 = Readable::read(reader)?;
1552                 if min_ver > SERIALIZATION_VERSION {
1553                         return Err(DecodeError::UnknownVersion);
1554                 }
1555
1556                 // Technically this can fail and serialize fail a round-trip, but only for serialization of
1557                 // barely-init'd ChannelMonitors that we can't do anything with.
1558                 let outpoint = OutPoint {
1559                         txid: Readable::read(reader)?,
1560                         index: Readable::read(reader)?,
1561                 };
1562                 let funding_txo = Some((outpoint, Readable::read(reader)?));
1563                 let commitment_transaction_number_obscure_factor = <U48 as Readable<R>>::read(reader)?.0;
1564
1565                 let key_storage = match <u8 as Readable<R>>::read(reader)? {
1566                         0 => {
1567                                 let revocation_base_key = Readable::read(reader)?;
1568                                 let htlc_base_key = Readable::read(reader)?;
1569                                 let delayed_payment_base_key = Readable::read(reader)?;
1570                                 let payment_base_key = Readable::read(reader)?;
1571                                 let shutdown_pubkey = Readable::read(reader)?;
1572                                 let prev_latest_per_commitment_point = match <u8 as Readable<R>>::read(reader)? {
1573                                         0 => None,
1574                                         1 => Some(Readable::read(reader)?),
1575                                         _ => return Err(DecodeError::InvalidValue),
1576                                 };
1577                                 let latest_per_commitment_point = match <u8 as Readable<R>>::read(reader)? {
1578                                         0 => None,
1579                                         1 => Some(Readable::read(reader)?),
1580                                         _ => return Err(DecodeError::InvalidValue),
1581                                 };
1582                                 KeyStorage::PrivMode {
1583                                         revocation_base_key,
1584                                         htlc_base_key,
1585                                         delayed_payment_base_key,
1586                                         payment_base_key,
1587                                         shutdown_pubkey,
1588                                         prev_latest_per_commitment_point,
1589                                         latest_per_commitment_point,
1590                                 }
1591                         },
1592                         _ => return Err(DecodeError::InvalidValue),
1593                 };
1594
1595                 let their_htlc_base_key = Some(Readable::read(reader)?);
1596                 let their_delayed_payment_base_key = Some(Readable::read(reader)?);
1597
1598                 let their_cur_revocation_points = {
1599                         let first_idx = <U48 as Readable<R>>::read(reader)?.0;
1600                         if first_idx == 0 {
1601                                 None
1602                         } else {
1603                                 let first_point = Readable::read(reader)?;
1604                                 let second_point_slice: [u8; 33] = Readable::read(reader)?;
1605                                 if second_point_slice[0..32] == [0; 32] && second_point_slice[32] == 0 {
1606                                         Some((first_idx, first_point, None))
1607                                 } else {
1608                                         Some((first_idx, first_point, Some(unwrap_obj!(PublicKey::from_slice(&secp_ctx, &second_point_slice)))))
1609                                 }
1610                         }
1611                 };
1612
1613                 let our_to_self_delay: u16 = Readable::read(reader)?;
1614                 let their_to_self_delay: Option<u16> = Some(Readable::read(reader)?);
1615
1616                 let mut old_secrets = [([0; 32], 1 << 48); 49];
1617                 for &mut (ref mut secret, ref mut idx) in old_secrets.iter_mut() {
1618                         *secret = Readable::read(reader)?;
1619                         *idx = Readable::read(reader)?;
1620                 }
1621
1622                 macro_rules! read_htlc_in_commitment {
1623                         () => {
1624                                 {
1625                                         let offered: bool = Readable::read(reader)?;
1626                                         let amount_msat: u64 = Readable::read(reader)?;
1627                                         let cltv_expiry: u32 = Readable::read(reader)?;
1628                                         let payment_hash: [u8; 32] = Readable::read(reader)?;
1629                                         let transaction_output_index: u32 = Readable::read(reader)?;
1630
1631                                         HTLCOutputInCommitment {
1632                                                 offered, amount_msat, cltv_expiry, payment_hash, transaction_output_index
1633                                         }
1634                                 }
1635                         }
1636                 }
1637
1638                 let remote_claimable_outpoints_len: u64 = Readable::read(reader)?;
1639                 let mut remote_claimable_outpoints = HashMap::with_capacity(cmp::min(remote_claimable_outpoints_len as usize, MAX_ALLOC_SIZE / 64));
1640                 for _ in 0..remote_claimable_outpoints_len {
1641                         let txid: Sha256dHash = Readable::read(reader)?;
1642                         let outputs_count: u64 = Readable::read(reader)?;
1643                         let mut outputs = Vec::with_capacity(cmp::min(outputs_count as usize, MAX_ALLOC_SIZE / 32));
1644                         for _ in 0..outputs_count {
1645                                 outputs.push(read_htlc_in_commitment!());
1646                         }
1647                         if let Some(_) = remote_claimable_outpoints.insert(txid, outputs) {
1648                                 return Err(DecodeError::InvalidValue);
1649                         }
1650                 }
1651
1652                 let remote_commitment_txn_on_chain_len: u64 = Readable::read(reader)?;
1653                 let mut remote_commitment_txn_on_chain = HashMap::with_capacity(cmp::min(remote_commitment_txn_on_chain_len as usize, MAX_ALLOC_SIZE / 32));
1654                 for _ in 0..remote_commitment_txn_on_chain_len {
1655                         let txid: Sha256dHash = Readable::read(reader)?;
1656                         let commitment_number = <U48 as Readable<R>>::read(reader)?.0;
1657                         let outputs_count = <u64 as Readable<R>>::read(reader)?;
1658                         let mut outputs = Vec::with_capacity(cmp::min(outputs_count as usize, MAX_ALLOC_SIZE / 8));
1659                         for _ in 0..outputs_count {
1660                                 outputs.push(Readable::read(reader)?);
1661                         }
1662                         if let Some(_) = remote_commitment_txn_on_chain.insert(txid, (commitment_number, outputs)) {
1663                                 return Err(DecodeError::InvalidValue);
1664                         }
1665                 }
1666
1667                 let remote_hash_commitment_number_len: u64 = Readable::read(reader)?;
1668                 let mut remote_hash_commitment_number = HashMap::with_capacity(cmp::min(remote_hash_commitment_number_len as usize, MAX_ALLOC_SIZE / 32));
1669                 for _ in 0..remote_hash_commitment_number_len {
1670                         let txid: [u8; 32] = Readable::read(reader)?;
1671                         let commitment_number = <U48 as Readable<R>>::read(reader)?.0;
1672                         if let Some(_) = remote_hash_commitment_number.insert(txid, commitment_number) {
1673                                 return Err(DecodeError::InvalidValue);
1674                         }
1675                 }
1676
1677                 macro_rules! read_local_tx {
1678                         () => {
1679                                 {
1680                                         let tx = match Transaction::consensus_decode(reader.by_ref()) {
1681                                                 Ok(tx) => tx,
1682                                                 Err(e) => match e {
1683                                                         encode::Error::Io(ioe) => return Err(DecodeError::Io(ioe)),
1684                                                         _ => return Err(DecodeError::InvalidValue),
1685                                                 },
1686                                         };
1687
1688                                         if tx.input.is_empty() {
1689                                                 // Ensure tx didn't hit the 0-input ambiguity case.
1690                                                 return Err(DecodeError::InvalidValue);
1691                                         }
1692
1693                                         let revocation_key = Readable::read(reader)?;
1694                                         let a_htlc_key = Readable::read(reader)?;
1695                                         let b_htlc_key = Readable::read(reader)?;
1696                                         let delayed_payment_key = Readable::read(reader)?;
1697                                         let feerate_per_kw: u64 = Readable::read(reader)?;
1698
1699                                         let htlc_outputs_len: u64 = Readable::read(reader)?;
1700                                         let mut htlc_outputs = Vec::with_capacity(cmp::min(htlc_outputs_len as usize, MAX_ALLOC_SIZE / 128));
1701                                         for _ in 0..htlc_outputs_len {
1702                                                 htlc_outputs.push((read_htlc_in_commitment!(), Readable::read(reader)?, Readable::read(reader)?));
1703                                         }
1704
1705                                         LocalSignedTx {
1706                                                 txid: tx.txid(),
1707                                                 tx, revocation_key, a_htlc_key, b_htlc_key, delayed_payment_key, feerate_per_kw, htlc_outputs
1708                                         }
1709                                 }
1710                         }
1711                 }
1712
1713                 let prev_local_signed_commitment_tx = match <u8 as Readable<R>>::read(reader)? {
1714                         0 => None,
1715                         1 => {
1716                                 Some(read_local_tx!())
1717                         },
1718                         _ => return Err(DecodeError::InvalidValue),
1719                 };
1720
1721                 let current_local_signed_commitment_tx = match <u8 as Readable<R>>::read(reader)? {
1722                         0 => None,
1723                         1 => {
1724                                 Some(read_local_tx!())
1725                         },
1726                         _ => return Err(DecodeError::InvalidValue),
1727                 };
1728
1729                 let current_remote_commitment_number = <U48 as Readable<R>>::read(reader)?.0;
1730
1731                 let payment_preimages_len: u64 = Readable::read(reader)?;
1732                 let mut payment_preimages = HashMap::with_capacity(cmp::min(payment_preimages_len as usize, MAX_ALLOC_SIZE / 32));
1733                 let mut sha = Sha256::new();
1734                 for _ in 0..payment_preimages_len {
1735                         let preimage: [u8; 32] = Readable::read(reader)?;
1736                         sha.reset();
1737                         sha.input(&preimage);
1738                         let mut hash = [0; 32];
1739                         sha.result(&mut hash);
1740                         if let Some(_) = payment_preimages.insert(hash, preimage) {
1741                                 return Err(DecodeError::InvalidValue);
1742                         }
1743                 }
1744
1745                 let last_block_hash: Sha256dHash = Readable::read(reader)?;
1746                 let destination_script = Readable::read(reader)?;
1747
1748                 Ok((last_block_hash.clone(), ChannelMonitor {
1749                         funding_txo,
1750                         commitment_transaction_number_obscure_factor,
1751
1752                         key_storage,
1753                         their_htlc_base_key,
1754                         their_delayed_payment_base_key,
1755                         their_cur_revocation_points,
1756
1757                         our_to_self_delay,
1758                         their_to_self_delay,
1759
1760                         old_secrets,
1761                         remote_claimable_outpoints,
1762                         remote_commitment_txn_on_chain,
1763                         remote_hash_commitment_number,
1764
1765                         prev_local_signed_commitment_tx,
1766                         current_local_signed_commitment_tx,
1767                         current_remote_commitment_number,
1768
1769                         payment_preimages,
1770
1771                         destination_script,
1772                         last_block_hash,
1773                         secp_ctx,
1774                         logger,
1775                 }))
1776         }
1777
1778 }
1779
1780 #[cfg(test)]
1781 mod tests {
1782         use bitcoin::blockdata::script::Script;
1783         use bitcoin::blockdata::transaction::Transaction;
1784         use crypto::digest::Digest;
1785         use hex;
1786         use ln::channelmonitor::ChannelMonitor;
1787         use ln::chan_utils::{HTLCOutputInCommitment, TxCreationKeys};
1788         use util::sha2::Sha256;
1789         use util::test_utils::TestLogger;
1790         use secp256k1::key::{SecretKey,PublicKey};
1791         use secp256k1::{Secp256k1, Signature};
1792         use rand::{thread_rng,Rng};
1793         use std::sync::Arc;
1794
1795         #[test]
1796         fn test_per_commitment_storage() {
1797                 // Test vectors from BOLT 3:
1798                 let mut secrets: Vec<[u8; 32]> = Vec::new();
1799                 let mut monitor: ChannelMonitor;
1800                 let secp_ctx = Secp256k1::new();
1801                 let logger = Arc::new(TestLogger::new());
1802
1803                 macro_rules! test_secrets {
1804                         () => {
1805                                 let mut idx = 281474976710655;
1806                                 for secret in secrets.iter() {
1807                                         assert_eq!(monitor.get_secret(idx).unwrap(), *secret);
1808                                         idx -= 1;
1809                                 }
1810                                 assert_eq!(monitor.get_min_seen_secret(), idx + 1);
1811                                 assert!(monitor.get_secret(idx).is_err());
1812                         };
1813                 }
1814
1815                 {
1816                         // insert_secret correct sequence
1817                         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(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[45; 32]).unwrap()), 0, Script::new(), logger.clone());
1818                         secrets.clear();
1819
1820                         secrets.push([0; 32]);
1821                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1822                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1823                         test_secrets!();
1824
1825                         secrets.push([0; 32]);
1826                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1827                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1828                         test_secrets!();
1829
1830                         secrets.push([0; 32]);
1831                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1832                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1833                         test_secrets!();
1834
1835                         secrets.push([0; 32]);
1836                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1837                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
1838                         test_secrets!();
1839
1840                         secrets.push([0; 32]);
1841                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
1842                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
1843                         test_secrets!();
1844
1845                         secrets.push([0; 32]);
1846                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
1847                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
1848                         test_secrets!();
1849
1850                         secrets.push([0; 32]);
1851                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
1852                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
1853                         test_secrets!();
1854
1855                         secrets.push([0; 32]);
1856                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
1857                         monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap();
1858                         test_secrets!();
1859                 }
1860
1861                 {
1862                         // insert_secret #1 incorrect
1863                         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(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[45; 32]).unwrap()), 0, Script::new(), logger.clone());
1864                         secrets.clear();
1865
1866                         secrets.push([0; 32]);
1867                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
1868                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1869                         test_secrets!();
1870
1871                         secrets.push([0; 32]);
1872                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1873                         assert_eq!(monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap_err().err,
1874                                         "Previous secret did not match new one");
1875                 }
1876
1877                 {
1878                         // insert_secret #2 incorrect (#1 derived from incorrect)
1879                         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(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[45; 32]).unwrap()), 0, Script::new(), logger.clone());
1880                         secrets.clear();
1881
1882                         secrets.push([0; 32]);
1883                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
1884                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1885                         test_secrets!();
1886
1887                         secrets.push([0; 32]);
1888                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("dddc3a8d14fddf2b68fa8c7fbad2748274937479dd0f8930d5ebb4ab6bd866a3").unwrap());
1889                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1890                         test_secrets!();
1891
1892                         secrets.push([0; 32]);
1893                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1894                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1895                         test_secrets!();
1896
1897                         secrets.push([0; 32]);
1898                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1899                         assert_eq!(monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap_err().err,
1900                                         "Previous secret did not match new one");
1901                 }
1902
1903                 {
1904                         // insert_secret #3 incorrect
1905                         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(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[45; 32]).unwrap()), 0, Script::new(), logger.clone());
1906                         secrets.clear();
1907
1908                         secrets.push([0; 32]);
1909                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1910                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1911                         test_secrets!();
1912
1913                         secrets.push([0; 32]);
1914                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1915                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1916                         test_secrets!();
1917
1918                         secrets.push([0; 32]);
1919                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c51a18b13e8527e579ec56365482c62f180b7d5760b46e9477dae59e87ed423a").unwrap());
1920                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1921                         test_secrets!();
1922
1923                         secrets.push([0; 32]);
1924                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1925                         assert_eq!(monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap_err().err,
1926                                         "Previous secret did not match new one");
1927                 }
1928
1929                 {
1930                         // insert_secret #4 incorrect (1,2,3 derived from incorrect)
1931                         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(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[45; 32]).unwrap()), 0, Script::new(), logger.clone());
1932                         secrets.clear();
1933
1934                         secrets.push([0; 32]);
1935                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
1936                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1937                         test_secrets!();
1938
1939                         secrets.push([0; 32]);
1940                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("dddc3a8d14fddf2b68fa8c7fbad2748274937479dd0f8930d5ebb4ab6bd866a3").unwrap());
1941                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1942                         test_secrets!();
1943
1944                         secrets.push([0; 32]);
1945                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c51a18b13e8527e579ec56365482c62f180b7d5760b46e9477dae59e87ed423a").unwrap());
1946                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1947                         test_secrets!();
1948
1949                         secrets.push([0; 32]);
1950                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("ba65d7b0ef55a3ba300d4e87af29868f394f8f138d78a7011669c79b37b936f4").unwrap());
1951                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
1952                         test_secrets!();
1953
1954                         secrets.push([0; 32]);
1955                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
1956                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
1957                         test_secrets!();
1958
1959                         secrets.push([0; 32]);
1960                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
1961                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
1962                         test_secrets!();
1963
1964                         secrets.push([0; 32]);
1965                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
1966                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
1967                         test_secrets!();
1968
1969                         secrets.push([0; 32]);
1970                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
1971                         assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap_err().err,
1972                                         "Previous secret did not match new one");
1973                 }
1974
1975                 {
1976                         // insert_secret #5 incorrect
1977                         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(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[45; 32]).unwrap()), 0, Script::new(), logger.clone());
1978                         secrets.clear();
1979
1980                         secrets.push([0; 32]);
1981                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1982                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1983                         test_secrets!();
1984
1985                         secrets.push([0; 32]);
1986                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1987                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1988                         test_secrets!();
1989
1990                         secrets.push([0; 32]);
1991                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1992                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1993                         test_secrets!();
1994
1995                         secrets.push([0; 32]);
1996                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1997                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
1998                         test_secrets!();
1999
2000                         secrets.push([0; 32]);
2001                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("631373ad5f9ef654bb3dade742d09504c567edd24320d2fcd68e3cc47e2ff6a6").unwrap());
2002                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
2003                         test_secrets!();
2004
2005                         secrets.push([0; 32]);
2006                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
2007                         assert_eq!(monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap_err().err,
2008                                         "Previous secret did not match new one");
2009                 }
2010
2011                 {
2012                         // insert_secret #6 incorrect (5 derived from incorrect)
2013                         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(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[45; 32]).unwrap()), 0, Script::new(), logger.clone());
2014                         secrets.clear();
2015
2016                         secrets.push([0; 32]);
2017                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2018                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2019                         test_secrets!();
2020
2021                         secrets.push([0; 32]);
2022                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2023                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2024                         test_secrets!();
2025
2026                         secrets.push([0; 32]);
2027                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2028                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2029                         test_secrets!();
2030
2031                         secrets.push([0; 32]);
2032                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2033                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
2034                         test_secrets!();
2035
2036                         secrets.push([0; 32]);
2037                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("631373ad5f9ef654bb3dade742d09504c567edd24320d2fcd68e3cc47e2ff6a6").unwrap());
2038                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
2039                         test_secrets!();
2040
2041                         secrets.push([0; 32]);
2042                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("b7e76a83668bde38b373970155c868a653304308f9896692f904a23731224bb1").unwrap());
2043                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
2044                         test_secrets!();
2045
2046                         secrets.push([0; 32]);
2047                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
2048                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
2049                         test_secrets!();
2050
2051                         secrets.push([0; 32]);
2052                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
2053                         assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap_err().err,
2054                                         "Previous secret did not match new one");
2055                 }
2056
2057                 {
2058                         // insert_secret #7 incorrect
2059                         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(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[45; 32]).unwrap()), 0, Script::new(), logger.clone());
2060                         secrets.clear();
2061
2062                         secrets.push([0; 32]);
2063                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2064                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2065                         test_secrets!();
2066
2067                         secrets.push([0; 32]);
2068                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2069                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2070                         test_secrets!();
2071
2072                         secrets.push([0; 32]);
2073                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2074                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2075                         test_secrets!();
2076
2077                         secrets.push([0; 32]);
2078                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2079                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
2080                         test_secrets!();
2081
2082                         secrets.push([0; 32]);
2083                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
2084                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
2085                         test_secrets!();
2086
2087                         secrets.push([0; 32]);
2088                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
2089                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
2090                         test_secrets!();
2091
2092                         secrets.push([0; 32]);
2093                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("e7971de736e01da8ed58b94c2fc216cb1dca9e326f3a96e7194fe8ea8af6c0a3").unwrap());
2094                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
2095                         test_secrets!();
2096
2097                         secrets.push([0; 32]);
2098                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
2099                         assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap_err().err,
2100                                         "Previous secret did not match new one");
2101                 }
2102
2103                 {
2104                         // insert_secret #8 incorrect
2105                         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(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[45; 32]).unwrap()), 0, Script::new(), logger.clone());
2106                         secrets.clear();
2107
2108                         secrets.push([0; 32]);
2109                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2110                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2111                         test_secrets!();
2112
2113                         secrets.push([0; 32]);
2114                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2115                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2116                         test_secrets!();
2117
2118                         secrets.push([0; 32]);
2119                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2120                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2121                         test_secrets!();
2122
2123                         secrets.push([0; 32]);
2124                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2125                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
2126                         test_secrets!();
2127
2128                         secrets.push([0; 32]);
2129                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
2130                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
2131                         test_secrets!();
2132
2133                         secrets.push([0; 32]);
2134                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
2135                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
2136                         test_secrets!();
2137
2138                         secrets.push([0; 32]);
2139                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
2140                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
2141                         test_secrets!();
2142
2143                         secrets.push([0; 32]);
2144                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a7efbc61aac46d34f77778bac22c8a20c6a46ca460addc49009bda875ec88fa4").unwrap());
2145                         assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap_err().err,
2146                                         "Previous secret did not match new one");
2147                 }
2148         }
2149
2150         #[test]
2151         fn test_prune_preimages() {
2152                 let secp_ctx = Secp256k1::new();
2153                 let logger = Arc::new(TestLogger::new());
2154                 let dummy_sig = Signature::from_der(&secp_ctx, &hex::decode("3045022100fa86fa9a36a8cd6a7bb8f06a541787d51371d067951a9461d5404de6b928782e02201c8b7c334c10aed8976a3a465be9a28abff4cb23acbf00022295b378ce1fa3cd").unwrap()[..]).unwrap();
2155
2156                 macro_rules! dummy_keys {
2157                         () => {
2158                                 {
2159                                         let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap());
2160                                         TxCreationKeys {
2161                                                 per_commitment_point: dummy_key.clone(),
2162                                                 revocation_key: dummy_key.clone(),
2163                                                 a_htlc_key: dummy_key.clone(),
2164                                                 b_htlc_key: dummy_key.clone(),
2165                                                 a_delayed_payment_key: dummy_key.clone(),
2166                                                 b_payment_key: dummy_key.clone(),
2167                                         }
2168                                 }
2169                         }
2170                 }
2171                 let dummy_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
2172
2173                 let mut preimages = Vec::new();
2174                 {
2175                         let mut rng  = thread_rng();
2176                         for _ in 0..20 {
2177                                 let mut preimage = [0; 32];
2178                                 rng.fill_bytes(&mut preimage);
2179                                 let mut sha = Sha256::new();
2180                                 sha.input(&preimage);
2181                                 let mut hash = [0; 32];
2182                                 sha.result(&mut hash);
2183                                 preimages.push((preimage, hash));
2184                         }
2185                 }
2186
2187                 macro_rules! preimages_slice_to_htlc_outputs {
2188                         ($preimages_slice: expr) => {
2189                                 {
2190                                         let mut res = Vec::new();
2191                                         for (idx, preimage) in $preimages_slice.iter().enumerate() {
2192                                                 res.push(HTLCOutputInCommitment {
2193                                                         offered: true,
2194                                                         amount_msat: 0,
2195                                                         cltv_expiry: 0,
2196                                                         payment_hash: preimage.1.clone(),
2197                                                         transaction_output_index: idx as u32,
2198                                                 });
2199                                         }
2200                                         res
2201                                 }
2202                         }
2203                 }
2204                 macro_rules! preimages_to_local_htlcs {
2205                         ($preimages_slice: expr) => {
2206                                 {
2207                                         let mut inp = preimages_slice_to_htlc_outputs!($preimages_slice);
2208                                         let res: Vec<_> = inp.drain(..).map(|e| { (e, dummy_sig.clone(), dummy_sig.clone()) }).collect();
2209                                         res
2210                                 }
2211                         }
2212                 }
2213
2214                 macro_rules! test_preimages_exist {
2215                         ($preimages_slice: expr, $monitor: expr) => {
2216                                 for preimage in $preimages_slice {
2217                                         assert!($monitor.payment_preimages.contains_key(&preimage.1));
2218                                 }
2219                         }
2220                 }
2221
2222                 // Prune with one old state and a local commitment tx holding a few overlaps with the
2223                 // old state.
2224                 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(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[45; 32]).unwrap()), 0, Script::new(), logger.clone());
2225                 monitor.set_their_to_self_delay(10);
2226
2227                 monitor.provide_latest_local_commitment_tx_info(dummy_tx.clone(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..10]));
2228                 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[5..15]), 281474976710655);
2229                 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[15..20]), 281474976710654);
2230                 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[17..20]), 281474976710653);
2231                 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[18..20]), 281474976710652);
2232                 for &(ref preimage, ref hash) in preimages.iter() {
2233                         monitor.provide_payment_preimage(hash, preimage);
2234                 }
2235
2236                 // Now provide a secret, pruning preimages 10-15
2237                 let mut secret = [0; 32];
2238                 secret[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2239                 monitor.provide_secret(281474976710655, secret.clone()).unwrap();
2240                 assert_eq!(monitor.payment_preimages.len(), 15);
2241                 test_preimages_exist!(&preimages[0..10], monitor);
2242                 test_preimages_exist!(&preimages[15..20], monitor);
2243
2244                 // Now provide a further secret, pruning preimages 15-17
2245                 secret[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2246                 monitor.provide_secret(281474976710654, secret.clone()).unwrap();
2247                 assert_eq!(monitor.payment_preimages.len(), 13);
2248                 test_preimages_exist!(&preimages[0..10], monitor);
2249                 test_preimages_exist!(&preimages[17..20], monitor);
2250
2251                 // Now update local commitment tx info, pruning only element 18 as we still care about the
2252                 // previous commitment tx's preimages too
2253                 monitor.provide_latest_local_commitment_tx_info(dummy_tx.clone(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..5]));
2254                 secret[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2255                 monitor.provide_secret(281474976710653, secret.clone()).unwrap();
2256                 assert_eq!(monitor.payment_preimages.len(), 12);
2257                 test_preimages_exist!(&preimages[0..10], monitor);
2258                 test_preimages_exist!(&preimages[18..20], monitor);
2259
2260                 // But if we do it again, we'll prune 5-10
2261                 monitor.provide_latest_local_commitment_tx_info(dummy_tx.clone(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..3]));
2262                 secret[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2263                 monitor.provide_secret(281474976710652, secret.clone()).unwrap();
2264                 assert_eq!(monitor.payment_preimages.len(), 5);
2265                 test_preimages_exist!(&preimages[0..5], monitor);
2266         }
2267
2268         // Further testing is done in the ChannelManager integration tests.
2269 }