git.bitcoin.ninja 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 //! ChannelMonitor objects are generated by ChannelManager in response to relevant
   4 //! messages/actions, and MUST be persisted to disk (and, preferably, remotely) before progress can
   5 //! be made in responding to certain messages, see ManyChannelMonitor for more.
   6 //! Note that ChannelMonitors are an important part of the lightning trust model and a copy of the
   7 //! latest ChannelMonitor must always be actively monitoring for chain updates (and no out-of-date
   8 //! ChannelMonitors should do so). Thus, if you're building rust-lightning into an HSM or other
   9 //! security-domain-separated system design, you should consider having multiple paths for
  10 //! ChannelMonitors to get out of the HSM and onto monitoring devices.
  11
  12 use bitcoin::blockdata::block::BlockHeader;
  13 use bitcoin::blockdata::transaction::{TxIn,TxOut,SigHashType,Transaction};
  14 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
  15 use bitcoin::blockdata::script::Script;
  16 use bitcoin::network::serialize;
  17 use bitcoin::util::hash::Sha256dHash;
  18 use bitcoin::util::bip143;
  19
  20 use crypto::digest::Digest;
  21
  22 use secp256k1::{Secp256k1,Message,Signature};
  23 use secp256k1::key::{SecretKey,PublicKey};
  24 use secp256k1;
  25
  26 use ln::msgs::{DecodeError, HandleError};
  27 use ln::chan_utils;
  28 use ln::chan_utils::HTLCOutputInCommitment;
  29 use chain::chaininterface::{ChainListener, ChainWatchInterface, BroadcasterInterface};
  30 use chain::transaction::OutPoint;
  31 use util::ser::Readable;
  32 use util::sha2::Sha256;
  33 use util::byte_utils;
  34
  35 use std::collections::HashMap;
  36 use std::sync::{Arc,Mutex};
  37 use std::{hash,cmp};
  38
  39 /// An error enum representing a failure to persist a channel monitor update.
  40 pub enum ChannelMonitorUpdateErr {
  41         /// Used to indicate a temporary failure (eg connection to a watchtower failed, but is expected
  42         /// to succeed at some point in the future).
  43         /// Such a failure will "freeze" a channel, preventing us from revoking old states or
  44         /// submitting new commitment transactions to the remote party.
  45         /// ChannelManager::test_restore_channel_monitor can be used to retry the update(s) and restore
  46         /// the channel to an operational state.
  47         TemporaryFailure,
  48         /// Used to indicate no further channel monitor updates will be allowed (eg we've moved on to a
  49         /// different watchtower and cannot update with all watchtowers that were previously informed
  50         /// of this channel). This will force-close the channel in question.
  51         PermanentFailure,
  52 }
  53
  54 /// Simple trait indicating ability to track a set of ChannelMonitors and multiplex events between
  55 /// them. Generally should be implemented by keeping a local SimpleManyChannelMonitor and passing
  56 /// events to it, while also taking any add_update_monitor events and passing them to some remote
  57 /// server(s).
  58 /// Note that any updates to a channel's monitor *must* be applied to each instance of the
  59 /// channel's monitor everywhere (including remote watchtowers) *before* this function returns. If
  60 /// an update occurs and a remote watchtower is left with old state, it may broadcast transactions
  61 /// which we have revoked, allowing our counterparty to claim all funds in the channel!
  62 pub trait ManyChannelMonitor: Send + Sync {
  63         /// Adds or updates a monitor for the given `funding_txo`.
  64         /// Implementor must also ensure that the funding_txo outpoint is registered with any relevant
  65         /// ChainWatchInterfaces such that the provided monitor receives block_connected callbacks with
  66         /// any spends of it.
  67         fn add_update_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor) -> Result<(), ChannelMonitorUpdateErr>;
  68 }
  69
  70 /// A simple implementation of a ManyChannelMonitor and ChainListener. Can be used to create a
  71 /// watchtower or watch our own channels.
  72 /// Note that you must provide your own key by which to refer to channels.
  73 /// If you're accepting remote monitors (ie are implementing a watchtower), you must verify that
  74 /// users cannot overwrite a given channel by providing a duplicate key. ie you should probably
  75 /// index by a PublicKey which is required to sign any updates.
  76 /// If you're using this for local monitoring of your own channels, you probably want to use
  77 /// `OutPoint` as the key, which will give you a ManyChannelMonitor implementation.
  78 pub struct SimpleManyChannelMonitor<Key> {
  79         #[cfg(test)] // Used in ChannelManager tests to manipulate channels directly
  80         pub monitors: Mutex<HashMap<Key, ChannelMonitor>>,
  81         #[cfg(not(test))]
  82         monitors: Mutex<HashMap<Key, ChannelMonitor>>,
  83         chain_monitor: Arc<ChainWatchInterface>,
  84         broadcaster: Arc<BroadcasterInterface>
  85 }
  86
  87 impl<Key : Send + cmp::Eq + hash::Hash> ChainListener for SimpleManyChannelMonitor<Key> {
  88         fn block_connected(&self, _header: &BlockHeader, height: u32, txn_matched: &[&Transaction], _indexes_of_txn_matched: &[u32]) {
  89                 let monitors = self.monitors.lock().unwrap();
  90                 for monitor in monitors.values() {
  91                         let txn_outputs = monitor.block_connected(txn_matched, height, &*self.broadcaster);
  92                         for (ref txid, ref outputs) in txn_outputs {
  93                                 for (idx, output) in outputs.iter().enumerate() {
  94                                         self.chain_monitor.install_watch_outpoint((txid.clone(), idx as u32), &output.script_pubkey);
  95                                 }
  96                         }
  97                 }
  98         }
  99
 100         fn block_disconnected(&self, _: &BlockHeader) { }
 101 }
 102
 103 impl<Key : Send + cmp::Eq + hash::Hash + 'static> SimpleManyChannelMonitor<Key> {
 104         /// Creates a new object which can be used to monitor several channels given the chain
 105         /// interface with which to register to receive notifications.
 106         pub fn new(chain_monitor: Arc<ChainWatchInterface>, broadcaster: Arc<BroadcasterInterface>) -> Arc<SimpleManyChannelMonitor<Key>> {
 107                 let res = Arc::new(SimpleManyChannelMonitor {
 108                         monitors: Mutex::new(HashMap::new()),
 109                         chain_monitor,
 110                         broadcaster
 111                 });
 112                 let weak_res = Arc::downgrade(&res);
 113                 res.chain_monitor.register_listener(weak_res);
 114                 res
 115         }
 116
 117         /// Adds or udpates the monitor which monitors the channel referred to by the given key.
 118         pub fn add_update_monitor_by_key(&self, key: Key, monitor: ChannelMonitor) -> Result<(), HandleError> {
 119                 let mut monitors = self.monitors.lock().unwrap();
 120                 match monitors.get_mut(&key) {
 121                         Some(orig_monitor) => return orig_monitor.insert_combine(monitor),
 122                         None => {}
 123                 };
 124                 match &monitor.funding_txo {
 125                         &None => self.chain_monitor.watch_all_txn(),
 126                         &Some((ref outpoint, ref script)) => {
 127                                 self.chain_monitor.install_watch_tx(&outpoint.txid, script);
 128                                 self.chain_monitor.install_watch_outpoint((outpoint.txid, outpoint.index as u32), script);
 129                         },
 130                 }
 131                 monitors.insert(key, monitor);
 132                 Ok(())
 133         }
 134 }
 135
 136 impl ManyChannelMonitor for SimpleManyChannelMonitor<OutPoint> {
 137         fn add_update_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor) -> Result<(), ChannelMonitorUpdateErr> {
 138                 match self.add_update_monitor_by_key(funding_txo, monitor) {
 139                         Ok(_) => Ok(()),
 140                         Err(_) => Err(ChannelMonitorUpdateErr::PermanentFailure),
 141                 }
 142         }
 143 }
 144
 145 /// If an HTLC expires within this many blocks, don't try to claim it in a shared transaction,
 146 /// instead claiming it in its own individual transaction.
 147 const CLTV_SHARED_CLAIM_BUFFER: u32 = 12;
 148 /// If an HTLC expires within this many blocks, force-close the channel to broadcast the
 149 /// HTLC-Success transaction.
 150 const CLTV_CLAIM_BUFFER: u32 = 6;
 151
 152 #[derive(Clone, PartialEq)]
 153 enum KeyStorage {
 154         PrivMode {
 155                 revocation_base_key: SecretKey,
 156                 htlc_base_key: SecretKey,
 157         },
 158         SigsMode {
 159                 revocation_base_key: PublicKey,
 160                 htlc_base_key: PublicKey,
 161                 sigs: HashMap<Sha256dHash, Signature>,
 162         }
 163 }
 164
 165 #[derive(Clone, PartialEq)]
 166 struct LocalSignedTx {
 167         /// txid of the transaction in tx, just used to make comparison faster
 168         txid: Sha256dHash,
 169         tx: Transaction,
 170         revocation_key: PublicKey,
 171         a_htlc_key: PublicKey,
 172         b_htlc_key: PublicKey,
 173         delayed_payment_key: PublicKey,
 174         feerate_per_kw: u64,
 175         htlc_outputs: Vec<(HTLCOutputInCommitment, Signature, Signature)>,
 176 }
 177
 178 const SERIALIZATION_VERSION: u8 = 1;
 179 const MIN_SERIALIZATION_VERSION: u8 = 1;
 180
 181 /// A ChannelMonitor handles chain events (blocks connected and disconnected) and generates
 182 /// on-chain transactions to ensure no loss of funds occurs.
 183 /// You MUST ensure that no ChannelMonitors for a given channel anywhere contain out-of-date
 184 /// information and are actively monitoring the chain.
 185 pub struct ChannelMonitor {
 186         funding_txo: Option<(OutPoint, Script)>,
 187         commitment_transaction_number_obscure_factor: u64,
 188
 189         key_storage: KeyStorage,
 190         delayed_payment_base_key: PublicKey,
 191         their_htlc_base_key: Option<PublicKey>,
 192         their_delayed_payment_base_key: Option<PublicKey>,
 193         // first is the idx of the first of the two revocation points
 194         their_cur_revocation_points: Option<(u64, PublicKey, Option<PublicKey>)>,
 195
 196         our_to_self_delay: u16,
 197         their_to_self_delay: Option<u16>,
 198
 199         old_secrets: [([u8; 32], u64); 49],
 200         remote_claimable_outpoints: HashMap<Sha256dHash, Vec<HTLCOutputInCommitment>>,
 201         /// We cannot identify HTLC-Success or HTLC-Timeout transactions by themselves on the chain.
 202         /// Nor can we figure out their commitment numbers without the commitment transaction they are
 203         /// spending. Thus, in order to claim them via revocation key, we track all the remote
 204         /// commitment transactions which we find on-chain, mapping them to the commitment number which
 205         /// can be used to derive the revocation key and claim the transactions.
 206         remote_commitment_txn_on_chain: Mutex<HashMap<Sha256dHash, u64>>,
 207         /// Cache used to make pruning of payment_preimages faster.
 208         /// Maps payment_hash values to commitment numbers for remote transactions for non-revoked
 209         /// remote transactions (ie should remain pretty small).
 210         /// Serialized to disk but should generally not be sent to Watchtowers.
 211         remote_hash_commitment_number: HashMap<[u8; 32], u64>,
 212
 213         // We store two local commitment transactions to avoid any race conditions where we may update
 214         // some monitors (potentially on watchtowers) but then fail to update others, resulting in the
 215         // various monitors for one channel being out of sync, and us broadcasting a local
 216         // transaction for which we have deleted claim information on some watchtowers.
 217         prev_local_signed_commitment_tx: Option<LocalSignedTx>,
 218         current_local_signed_commitment_tx: Option<LocalSignedTx>,
 219
 220         payment_preimages: HashMap<[u8; 32], [u8; 32]>,
 221
 222         destination_script: Script,
 223         secp_ctx: Secp256k1<secp256k1::All>, //TODO: dedup this a bit...
 224 }
 225 impl Clone for ChannelMonitor {
 226         fn clone(&self) -> Self {
 227                 ChannelMonitor {
 228                         funding_txo: self.funding_txo.clone(),
 229                         commitment_transaction_number_obscure_factor: self.commitment_transaction_number_obscure_factor.clone(),
 230
 231                         key_storage: self.key_storage.clone(),
 232                         delayed_payment_base_key: self.delayed_payment_base_key.clone(),
 233                         their_htlc_base_key: self.their_htlc_base_key.clone(),
 234                         their_delayed_payment_base_key: self.their_delayed_payment_base_key.clone(),
 235                         their_cur_revocation_points: self.their_cur_revocation_points.clone(),
 236
 237                         our_to_self_delay: self.our_to_self_delay,
 238                         their_to_self_delay: self.their_to_self_delay,
 239
 240                         old_secrets: self.old_secrets.clone(),
 241                         remote_claimable_outpoints: self.remote_claimable_outpoints.clone(),
 242                         remote_commitment_txn_on_chain: Mutex::new((*self.remote_commitment_txn_on_chain.lock().unwrap()).clone()),
 243                         remote_hash_commitment_number: self.remote_hash_commitment_number.clone(),
 244
 245                         prev_local_signed_commitment_tx: self.prev_local_signed_commitment_tx.clone(),
 246                         current_local_signed_commitment_tx: self.current_local_signed_commitment_tx.clone(),
 247
 248                         payment_preimages: self.payment_preimages.clone(),
 249
 250                         destination_script: self.destination_script.clone(),
 251                         secp_ctx: self.secp_ctx.clone(),
 252                 }
 253         }
 254 }
 255
 256 #[cfg(any(test, feature = "fuzztarget"))]
 257 /// Used only in testing and fuzztarget to check serialization roundtrips don't change the
 258 /// underlying object
 259 impl PartialEq for ChannelMonitor {
 260         fn eq(&self, other: &Self) -> bool {
 261                 if self.funding_txo != other.funding_txo ||
 262                         self.commitment_transaction_number_obscure_factor != other.commitment_transaction_number_obscure_factor ||
 263                         self.key_storage != other.key_storage ||
 264                         self.delayed_payment_base_key != other.delayed_payment_base_key ||
 265                         self.their_htlc_base_key != other.their_htlc_base_key ||
 266                         self.their_delayed_payment_base_key != other.their_delayed_payment_base_key ||
 267                         self.their_cur_revocation_points != other.their_cur_revocation_points ||
 268                         self.our_to_self_delay != other.our_to_self_delay ||
 269                         self.their_to_self_delay != other.their_to_self_delay ||
 270                         self.remote_claimable_outpoints != other.remote_claimable_outpoints ||
 271                         self.remote_hash_commitment_number != other.remote_hash_commitment_number ||
 272                         self.prev_local_signed_commitment_tx != other.prev_local_signed_commitment_tx ||
 273                         self.current_local_signed_commitment_tx != other.current_local_signed_commitment_tx ||
 274                         self.payment_preimages != other.payment_preimages ||
 275                         self.destination_script != other.destination_script
 276                 {
 277                         false
 278                 } else {
 279                         for (&(ref secret, ref idx), &(ref o_secret, ref o_idx)) in self.old_secrets.iter().zip(other.old_secrets.iter()) {
 280                                 if secret != o_secret || idx != o_idx {
 281                                         return false
 282                                 }
 283                         }
 284                         let us = self.remote_commitment_txn_on_chain.lock().unwrap();
 285                         let them = other.remote_commitment_txn_on_chain.lock().unwrap();
 286                         *us == *them
 287                 }
 288         }
 289 }
 290
 291 impl ChannelMonitor {
 292         pub(super) fn new(revocation_base_key: &SecretKey, delayed_payment_base_key: &PublicKey, htlc_base_key: &SecretKey, our_to_self_delay: u16, destination_script: Script) -> ChannelMonitor {
 293                 ChannelMonitor {
 294                         funding_txo: None,
 295                         commitment_transaction_number_obscure_factor: 0,
 296
 297                         key_storage: KeyStorage::PrivMode {
 298                                 revocation_base_key: revocation_base_key.clone(),
 299                                 htlc_base_key: htlc_base_key.clone(),
 300                         },
 301                         delayed_payment_base_key: delayed_payment_base_key.clone(),
 302                         their_htlc_base_key: None,
 303                         their_delayed_payment_base_key: None,
 304                         their_cur_revocation_points: None,
 305
 306                         our_to_self_delay: our_to_self_delay,
 307                         their_to_self_delay: None,
 308
 309                         old_secrets: [([0; 32], 1 << 48); 49],
 310                         remote_claimable_outpoints: HashMap::new(),
 311                         remote_commitment_txn_on_chain: Mutex::new(HashMap::new()),
 312                         remote_hash_commitment_number: HashMap::new(),
 313
 314                         prev_local_signed_commitment_tx: None,
 315                         current_local_signed_commitment_tx: None,
 316
 317                         payment_preimages: HashMap::new(),
 318
 319                         destination_script: destination_script,
 320                         secp_ctx: Secp256k1::new(),
 321                 }
 322         }
 323
 324         #[inline]
 325         fn place_secret(idx: u64) -> u8 {
 326                 for i in 0..48 {
 327                         if idx & (1 << i) == (1 << i) {
 328                                 return i
 329                         }
 330                 }
 331                 48
 332         }
 333
 334         #[inline]
 335         fn derive_secret(secret: [u8; 32], bits: u8, idx: u64) -> [u8; 32] {
 336                 let mut res: [u8; 32] = secret;
 337                 for i in 0..bits {
 338                         let bitpos = bits - 1 - i;
 339                         if idx & (1 << bitpos) == (1 << bitpos) {
 340                                 res[(bitpos / 8) as usize] ^= 1 << (bitpos & 7);
 341                                 let mut sha = Sha256::new();
 342                                 sha.input(&res);
 343                                 sha.result(&mut res);
 344                         }
 345                 }
 346                 res
 347         }
 348
 349         /// Inserts a revocation secret into this channel monitor. Also optionally tracks the next
 350         /// revocation point which may be required to claim HTLC outputs which we know the preimage of
 351         /// in case the remote end force-closes using their latest state. Prunes old preimages if neither
 352         /// needed by local commitment transactions HTCLs nor by remote ones. Unless we haven't already seen remote
 353         /// commitment transaction's secret, they are de facto pruned (we can use revocation key).
 354         pub(super) fn provide_secret(&mut self, idx: u64, secret: [u8; 32], their_next_revocation_point: Option<(u64, PublicKey)>) -> Result<(), HandleError> {
 355                 let pos = ChannelMonitor::place_secret(idx);
 356                 for i in 0..pos {
 357                         let (old_secret, old_idx) = self.old_secrets[i as usize];
 358                         if ChannelMonitor::derive_secret(secret, pos, old_idx) != old_secret {
 359                                 return Err(HandleError{err: "Previous secret did not match new one", action: None})
 360                         }
 361                 }
 362                 self.old_secrets[pos as usize] = (secret, idx);
 363
 364                 if let Some(new_revocation_point) = their_next_revocation_point {
 365                         match self.their_cur_revocation_points {
 366                                 Some(old_points) => {
 367                                         if old_points.0 == new_revocation_point.0 + 1 {
 368                                                 self.their_cur_revocation_points = Some((old_points.0, old_points.1, Some(new_revocation_point.1)));
 369                                         } else if old_points.0 == new_revocation_point.0 + 2 {
 370                                                 if let Some(old_second_point) = old_points.2 {
 371                                                         self.their_cur_revocation_points = Some((old_points.0 - 1, old_second_point, Some(new_revocation_point.1)));
 372                                                 } else {
 373                                                         self.their_cur_revocation_points = Some((new_revocation_point.0, new_revocation_point.1, None));
 374                                                 }
 375                                         } else {
 376                                                 self.their_cur_revocation_points = Some((new_revocation_point.0, new_revocation_point.1, None));
 377                                         }
 378                                 },
 379                                 None => {
 380                                         self.their_cur_revocation_points = Some((new_revocation_point.0, new_revocation_point.1, None));
 381                                 }
 382                         }
 383                 }
 384
 385                 if !self.payment_preimages.is_empty() {
 386                         let local_signed_commitment_tx = self.current_local_signed_commitment_tx.as_ref().expect("Channel needs at least an initial commitment tx !");
 387                         let prev_local_signed_commitment_tx = self.prev_local_signed_commitment_tx.as_ref();
 388                         let min_idx = self.get_min_seen_secret();
 389                         let remote_hash_commitment_number = &mut self.remote_hash_commitment_number;
 390
 391                         self.payment_preimages.retain(|&k, _| {
 392                                 for &(ref htlc, _, _) in &local_signed_commitment_tx.htlc_outputs {
 393                                         if k == htlc.payment_hash {
 394                                                 return true
 395                                         }
 396                                 }
 397                                 if let Some(prev_local_commitment_tx) = prev_local_signed_commitment_tx {
 398                                         for &(ref htlc, _, _) in prev_local_commitment_tx.htlc_outputs.iter() {
 399                                                 if k == htlc.payment_hash {
 400                                                         return true
 401                                                 }
 402                                         }
 403                                 }
 404                                 let contains = if let Some(cn) = remote_hash_commitment_number.get(&k) {
 405                                         if *cn < min_idx {
 406                                                 return true
 407                                         }
 408                                         true
 409                                 } else { false };
 410                                 if contains {
 411                                         remote_hash_commitment_number.remove(&k);
 412                                 }
 413                                 false
 414                         });
 415                 }
 416
 417                 Ok(())
 418         }
 419
 420         /// Informs this monitor of the latest remote (ie non-broadcastable) commitment transaction.
 421         /// The monitor watches for it to be broadcasted and then uses the HTLC information (and
 422         /// possibly future revocation/preimage information) to claim outputs where possible.
 423         /// We cache also the mapping hash:commitment number to lighten pruning of old preimages by watchtowers.
 424         pub(super) fn provide_latest_remote_commitment_tx_info(&mut self, unsigned_commitment_tx: &Transaction, htlc_outputs: Vec<HTLCOutputInCommitment>, commitment_number: u64) {
 425                 // TODO: Encrypt the htlc_outputs data with the single-hash of the commitment transaction
 426                 // so that a remote monitor doesn't learn anything unless there is a malicious close.
 427                 // (only maybe, sadly we cant do the same for local info, as we need to be aware of
 428                 // timeouts)
 429                 for htlc in &htlc_outputs {
 430                         self.remote_hash_commitment_number.insert(htlc.payment_hash, commitment_number);
 431                 }
 432                 self.remote_claimable_outpoints.insert(unsigned_commitment_tx.txid(), htlc_outputs);
 433         }
 434
 435         /// Informs this monitor of the latest local (ie broadcastable) commitment transaction. The
 436         /// monitor watches for timeouts and may broadcast it if we approach such a timeout. Thus, it
 437         /// is important that any clones of this channel monitor (including remote clones) by kept
 438         /// up-to-date as our local commitment transaction is updated.
 439         /// Panics if set_their_to_self_delay has never been called.
 440         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)>) {
 441                 assert!(self.their_to_self_delay.is_some());
 442                 self.prev_local_signed_commitment_tx = self.current_local_signed_commitment_tx.take();
 443                 self.current_local_signed_commitment_tx = Some(LocalSignedTx {
 444                         txid: signed_commitment_tx.txid(),
 445                         tx: signed_commitment_tx,
 446                         revocation_key: local_keys.revocation_key,
 447                         a_htlc_key: local_keys.a_htlc_key,
 448                         b_htlc_key: local_keys.b_htlc_key,
 449                         delayed_payment_key: local_keys.a_delayed_payment_key,
 450                         feerate_per_kw,
 451                         htlc_outputs,
 452                 });
 453         }
 454
 455         /// Provides a payment_hash->payment_preimage mapping. Will be automatically pruned when all
 456         /// commitment_tx_infos which contain the payment hash have been revoked.
 457         pub(super) fn provide_payment_preimage(&mut self, payment_hash: &[u8; 32], payment_preimage: &[u8; 32]) {
 458                 self.payment_preimages.insert(payment_hash.clone(), payment_preimage.clone());
 459         }
 460
 461         /// Combines this ChannelMonitor with the information contained in the other ChannelMonitor.
 462         /// After a successful call this ChannelMonitor is up-to-date and is safe to use to monitor the
 463         /// chain for new blocks/transactions.
 464         pub fn insert_combine(&mut self, mut other: ChannelMonitor) -> Result<(), HandleError> {
 465                 if self.funding_txo.is_some() {
 466                         // We should be able to compare the entire funding_txo, but in fuzztarget its trivially
 467                         // easy to collide the funding_txo hash and have a different scriptPubKey.
 468                         if other.funding_txo.is_some() && other.funding_txo.as_ref().unwrap().0 != self.funding_txo.as_ref().unwrap().0 {
 469                                 return Err(HandleError{err: "Funding transaction outputs are not identical!", action: None});
 470                         }
 471                 } else {
 472                         self.funding_txo = other.funding_txo.take();
 473                 }
 474                 let other_min_secret = other.get_min_seen_secret();
 475                 let our_min_secret = self.get_min_seen_secret();
 476                 if our_min_secret > other_min_secret {
 477                         self.provide_secret(other_min_secret, other.get_secret(other_min_secret).unwrap(), None)?;
 478                 }
 479                 if our_min_secret >= other_min_secret {
 480                         self.their_cur_revocation_points = other.their_cur_revocation_points;
 481                         for (txid, htlcs) in other.remote_claimable_outpoints.drain() {
 482                                 self.remote_claimable_outpoints.insert(txid, htlcs);
 483                         }
 484                         if let Some(local_tx) = other.prev_local_signed_commitment_tx {
 485                                 self.prev_local_signed_commitment_tx = Some(local_tx);
 486                         }
 487                         if let Some(local_tx) = other.current_local_signed_commitment_tx {
 488                                 self.current_local_signed_commitment_tx = Some(local_tx);
 489                         }
 490                         self.payment_preimages = other.payment_preimages;
 491                 }
 492                 Ok(())
 493         }
 494
 495         /// Panics if commitment_transaction_number_obscure_factor doesn't fit in 48 bits
 496         pub(super) fn set_commitment_obscure_factor(&mut self, commitment_transaction_number_obscure_factor: u64) {
 497                 assert!(commitment_transaction_number_obscure_factor < (1 << 48));
 498                 self.commitment_transaction_number_obscure_factor = commitment_transaction_number_obscure_factor;
 499         }
 500
 501         /// Allows this monitor to scan only for transactions which are applicable. Note that this is
 502         /// optional, without it this monitor cannot be used in an SPV client, but you may wish to
 503         /// avoid this (or call unset_funding_info) on a monitor you wish to send to a watchtower as it
 504         /// provides slightly better privacy.
 505         /// It's the responsibility of the caller to register outpoint and script with passing the former
 506         /// value as key to add_update_monitor.
 507         pub(super) fn set_funding_info(&mut self, funding_info: (OutPoint, Script)) {
 508                 self.funding_txo = Some(funding_info);
 509         }
 510
 511         /// We log these base keys at channel opening to being able to rebuild redeemscript in case of leaked revoked commit tx
 512         pub(super) fn set_their_base_keys(&mut self, their_htlc_base_key: &PublicKey, their_delayed_payment_base_key: &PublicKey) {
 513                 self.their_htlc_base_key = Some(their_htlc_base_key.clone());
 514                 self.their_delayed_payment_base_key = Some(their_delayed_payment_base_key.clone());
 515         }
 516
 517         pub(super) fn set_their_to_self_delay(&mut self, their_to_self_delay: u16) {
 518                 self.their_to_self_delay = Some(their_to_self_delay);
 519         }
 520
 521         pub(super) fn unset_funding_info(&mut self) {
 522                 self.funding_txo = None;
 523         }
 524
 525         /// Gets the funding transaction outpoint of the channel this ChannelMonitor is monitoring for.
 526         pub fn get_funding_txo(&self) -> Option<OutPoint> {
 527                 match self.funding_txo {
 528                         Some((outpoint, _)) => Some(outpoint),
 529                         None => None
 530                 }
 531         }
 532
 533         /// Serializes into a vec, with various modes for the exposed pub fns
 534         fn serialize(&self, for_local_storage: bool) -> Vec<u8> {
 535                 let mut res = Vec::new();
 536                 res.push(SERIALIZATION_VERSION);
 537                 res.push(MIN_SERIALIZATION_VERSION);
 538
 539                 match &self.funding_txo {
 540                         &Some((ref outpoint, ref script)) => {
 541                                 res.extend_from_slice(&outpoint.txid[..]);
 542                                 res.extend_from_slice(&byte_utils::be16_to_array(outpoint.index));
 543                                 res.extend_from_slice(&byte_utils::be64_to_array(script.len() as u64));
 544                                 res.extend_from_slice(&script[..]);
 545                         },
 546                         &None => {
 547                                 // We haven't even been initialized...not sure why anyone is serializing us, but
 548                                 // not much to give them.
 549                                 return res;
 550                         },
 551                 }
 552
 553                 // Set in initial Channel-object creation, so should always be set by now:
 554                 res.extend_from_slice(&byte_utils::be48_to_array(self.commitment_transaction_number_obscure_factor));
 555
 556                 match self.key_storage {
 557                         KeyStorage::PrivMode { ref revocation_base_key, ref htlc_base_key } => {
 558                                 res.push(0);
 559                                 res.extend_from_slice(&revocation_base_key[..]);
 560                                 res.extend_from_slice(&htlc_base_key[..]);
 561                         },
 562                         KeyStorage::SigsMode { .. } => unimplemented!(),
 563                 }
 564
 565                 res.extend_from_slice(&self.delayed_payment_base_key.serialize());
 566                 res.extend_from_slice(&self.their_htlc_base_key.as_ref().unwrap().serialize());
 567                 res.extend_from_slice(&self.their_delayed_payment_base_key.as_ref().unwrap().serialize());
 568
 569                 match self.their_cur_revocation_points {
 570                         Some((idx, pubkey, second_option)) => {
 571                                 res.extend_from_slice(&byte_utils::be48_to_array(idx));
 572                                 res.extend_from_slice(&pubkey.serialize());
 573                                 match second_option {
 574                                         Some(second_pubkey) => {
 575                                                 res.extend_from_slice(&second_pubkey.serialize());
 576                                         },
 577                                         None => {
 578                                                 res.extend_from_slice(&[0; 33]);
 579                                         },
 580                                 }
 581                         },
 582                         None => {
 583                                 res.extend_from_slice(&byte_utils::be48_to_array(0));
 584                         },
 585                 }
 586
 587                 res.extend_from_slice(&byte_utils::be16_to_array(self.our_to_self_delay));
 588                 res.extend_from_slice(&byte_utils::be16_to_array(self.their_to_self_delay.unwrap()));
 589
 590                 for &(ref secret, ref idx) in self.old_secrets.iter() {
 591                         res.extend_from_slice(secret);
 592                         res.extend_from_slice(&byte_utils::be64_to_array(*idx));
 593                 }
 594
 595                 macro_rules! serialize_htlc_in_commitment {
 596                         ($htlc_output: expr) => {
 597                                 res.push($htlc_output.offered as u8);
 598                                 res.extend_from_slice(&byte_utils::be64_to_array($htlc_output.amount_msat));
 599                                 res.extend_from_slice(&byte_utils::be32_to_array($htlc_output.cltv_expiry));
 600                                 res.extend_from_slice(&$htlc_output.payment_hash);
 601                                 res.extend_from_slice(&byte_utils::be32_to_array($htlc_output.transaction_output_index));
 602                         }
 603                 }
 604
 605                 res.extend_from_slice(&byte_utils::be64_to_array(self.remote_claimable_outpoints.len() as u64));
 606                 for (txid, htlc_outputs) in self.remote_claimable_outpoints.iter() {
 607                         res.extend_from_slice(&txid[..]);
 608                         res.extend_from_slice(&byte_utils::be64_to_array(htlc_outputs.len() as u64));
 609                         for htlc_output in htlc_outputs.iter() {
 610                                 serialize_htlc_in_commitment!(htlc_output);
 611                         }
 612                 }
 613
 614                 {
 615                         let remote_commitment_txn_on_chain = self.remote_commitment_txn_on_chain.lock().unwrap();
 616                         res.extend_from_slice(&byte_utils::be64_to_array(remote_commitment_txn_on_chain.len() as u64));
 617                         for (txid, commitment_number) in remote_commitment_txn_on_chain.iter() {
 618                                 res.extend_from_slice(&txid[..]);
 619                                 res.extend_from_slice(&byte_utils::be48_to_array(*commitment_number));
 620                         }
 621                 }
 622
 623                 if for_local_storage {
 624                         res.extend_from_slice(&byte_utils::be64_to_array(self.remote_hash_commitment_number.len() as u64));
 625                         for (payment_hash, commitment_number) in self.remote_hash_commitment_number.iter() {
 626                                 res.extend_from_slice(payment_hash);
 627                                 res.extend_from_slice(&byte_utils::be48_to_array(*commitment_number));
 628                         }
 629                 } else {
 630                         res.extend_from_slice(&byte_utils::be64_to_array(0));
 631                 }
 632
 633                 macro_rules! serialize_local_tx {
 634                         ($local_tx: expr) => {
 635                                 let tx_ser = serialize::serialize(&$local_tx.tx).unwrap();
 636                                 res.extend_from_slice(&byte_utils::be64_to_array(tx_ser.len() as u64));
 637                                 res.extend_from_slice(&tx_ser);
 638
 639                                 res.extend_from_slice(&$local_tx.revocation_key.serialize());
 640                                 res.extend_from_slice(&$local_tx.a_htlc_key.serialize());
 641                                 res.extend_from_slice(&$local_tx.b_htlc_key.serialize());
 642                                 res.extend_from_slice(&$local_tx.delayed_payment_key.serialize());
 643
 644                                 res.extend_from_slice(&byte_utils::be64_to_array($local_tx.feerate_per_kw));
 645                                 res.extend_from_slice(&byte_utils::be64_to_array($local_tx.htlc_outputs.len() as u64));
 646                                 for &(ref htlc_output, ref their_sig, ref our_sig) in $local_tx.htlc_outputs.iter() {
 647                                         serialize_htlc_in_commitment!(htlc_output);
 648                                         res.extend_from_slice(&their_sig.serialize_compact(&self.secp_ctx));
 649                                         res.extend_from_slice(&our_sig.serialize_compact(&self.secp_ctx));
 650                                 }
 651                         }
 652                 }
 653
 654                 if let Some(ref prev_local_tx) = self.prev_local_signed_commitment_tx {
 655                         res.push(1);
 656                         serialize_local_tx!(prev_local_tx);
 657                 } else {
 658                         res.push(0);
 659                 }
 660
 661                 if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
 662                         res.push(1);
 663                         serialize_local_tx!(cur_local_tx);
 664                 } else {
 665                         res.push(0);
 666                 }
 667
 668                 res.extend_from_slice(&byte_utils::be64_to_array(self.payment_preimages.len() as u64));
 669                 for payment_preimage in self.payment_preimages.values() {
 670                         res.extend_from_slice(payment_preimage);
 671                 }
 672
 673                 res.extend_from_slice(&byte_utils::be64_to_array(self.destination_script.len() as u64));
 674                 res.extend_from_slice(&self.destination_script[..]);
 675
 676                 res
 677         }
 678
 679         /// Encodes this monitor into a byte array, suitable for writing to disk.
 680         pub fn serialize_for_disk(&self) -> Vec<u8> {
 681                 self.serialize(true)
 682         }
 683
 684         /// Encodes this monitor into a byte array, suitable for sending to a remote watchtower
 685         pub fn serialize_for_watchtower(&self) -> Vec<u8> {
 686                 self.serialize(false)
 687         }
 688
 689         //TODO: Functions to serialize/deserialize (with different forms depending on which information
 690         //we want to leave out (eg funding_txo, etc).
 691
 692         /// Can only fail if idx is < get_min_seen_secret
 693         pub(super) fn get_secret(&self, idx: u64) -> Result<[u8; 32], HandleError> {
 694                 for i in 0..self.old_secrets.len() {
 695                         if (idx & (!((1 << i) - 1))) == self.old_secrets[i].1 {
 696                                 return Ok(ChannelMonitor::derive_secret(self.old_secrets[i].0, i as u8, idx))
 697                         }
 698                 }
 699                 assert!(idx < self.get_min_seen_secret());
 700                 Err(HandleError{err: "idx too low", action: None})
 701         }
 702
 703         pub(super) fn get_min_seen_secret(&self) -> u64 {
 704                 //TODO This can be optimized?
 705                 let mut min = 1 << 48;
 706                 for &(_, idx) in self.old_secrets.iter() {
 707                         if idx < min {
 708                                 min = idx;
 709                         }
 710                 }
 711                 min
 712         }
 713
 714         /// Attempts to claim a remote commitment transaction's outputs using the revocation key and
 715         /// data in remote_claimable_outpoints. Will directly claim any HTLC outputs which expire at a
 716         /// height > height + CLTV_SHARED_CLAIM_BUFFER. In any case, will install monitoring for
 717         /// HTLC-Success/HTLC-Timeout transactions.
 718         fn check_spend_remote_transaction(&self, tx: &Transaction, height: u32) -> (Vec<Transaction>, (Sha256dHash, Vec<TxOut>)) {
 719                 // Most secp and related errors trying to create keys means we have no hope of constructing
 720                 // a spend transaction...so we return no transactions to broadcast
 721                 let mut txn_to_broadcast = Vec::new();
 722                 let mut watch_outputs = Vec::new();
 723
 724                 let commitment_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
 725                 let per_commitment_option = self.remote_claimable_outpoints.get(&commitment_txid);
 726
 727                 macro_rules! ignore_error {
 728                         ( $thing : expr ) => {
 729                                 match $thing {
 730                                         Ok(a) => a,
 731                                         Err(_) => return (txn_to_broadcast, (commitment_txid, watch_outputs))
 732                                 }
 733                         };
 734                 }
 735
 736                 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);
 737                 if commitment_number >= self.get_min_seen_secret() {
 738                         let secret = self.get_secret(commitment_number).unwrap();
 739                         let per_commitment_key = ignore_error!(SecretKey::from_slice(&self.secp_ctx, &secret));
 740                         let (revocation_pubkey, b_htlc_key) = match self.key_storage {
 741                                 KeyStorage::PrivMode { ref revocation_base_key, ref htlc_base_key } => {
 742                                         let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
 743                                         (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &PublicKey::from_secret_key(&self.secp_ctx, &revocation_base_key))),
 744                                         ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &PublicKey::from_secret_key(&self.secp_ctx, &htlc_base_key))))
 745                                 },
 746                                 KeyStorage::SigsMode { ref revocation_base_key, ref htlc_base_key, .. } => {
 747                                         let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
 748                                         (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &revocation_base_key)),
 749                                         ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &htlc_base_key)))
 750                                 },
 751                         };
 752                         let delayed_key = ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key), &self.delayed_payment_base_key));
 753                         let a_htlc_key = match self.their_htlc_base_key {
 754                                 None => return (txn_to_broadcast, (commitment_txid, watch_outputs)),
 755                                 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)),
 756                         };
 757
 758                         let revokeable_redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.our_to_self_delay, &delayed_key);
 759                         let revokeable_p2wsh = revokeable_redeemscript.to_v0_p2wsh();
 760
 761                         let mut total_value = 0;
 762                         let mut values = Vec::new();
 763                         let mut inputs = Vec::new();
 764                         let mut htlc_idxs = Vec::new();
 765
 766                         for (idx, outp) in tx.output.iter().enumerate() {
 767                                 if outp.script_pubkey == revokeable_p2wsh {
 768                                         inputs.push(TxIn {
 769                                                 previous_output: BitcoinOutPoint {
 770                                                         txid: commitment_txid,
 771                                                         vout: idx as u32,
 772                                                 },
 773                                                 script_sig: Script::new(),
 774                                                 sequence: 0xfffffffd,
 775                                                 witness: Vec::new(),
 776                                         });
 777                                         htlc_idxs.push(None);
 778                                         values.push(outp.value);
 779                                         total_value += outp.value;
 780                                         break; // There can only be one of these
 781                                 }
 782                         }
 783
 784                         macro_rules! sign_input {
 785                                 ($sighash_parts: expr, $input: expr, $htlc_idx: expr, $amount: expr) => {
 786                                         {
 787                                                 let (sig, redeemscript) = match self.key_storage {
 788                                                         KeyStorage::PrivMode { ref revocation_base_key, .. } => {
 789                                                                 let redeemscript = if $htlc_idx.is_none() { revokeable_redeemscript.clone() } else {
 790                                                                         let htlc = &per_commitment_option.unwrap()[$htlc_idx.unwrap()];
 791                                                                         chan_utils::get_htlc_redeemscript_with_explicit_keys(htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey)
 792                                                                 };
 793                                                                 let sighash = ignore_error!(Message::from_slice(&$sighash_parts.sighash_all(&$input, &redeemscript, $amount)[..]));
 794                                                                 let revocation_key = ignore_error!(chan_utils::derive_private_revocation_key(&self.secp_ctx, &per_commitment_key, &revocation_base_key));
 795                                                                 (self.secp_ctx.sign(&sighash, &revocation_key), redeemscript)
 796                                                         },
 797                                                         KeyStorage::SigsMode { .. } => {
 798                                                                 unimplemented!();
 799                                                         }
 800                                                 };
 801                                                 $input.witness.push(sig.serialize_der(&self.secp_ctx).to_vec());
 802                                                 $input.witness[0].push(SigHashType::All as u8);
 803                                                 if $htlc_idx.is_none() {
 804                                                         $input.witness.push(vec!(1));
 805                                                 } else {
 806                                                         $input.witness.push(revocation_pubkey.serialize().to_vec());
 807                                                 }
 808                                                 $input.witness.push(redeemscript.into_bytes());
 809                                         }
 810                                 }
 811                         }
 812
 813                         if let Some(per_commitment_data) = per_commitment_option {
 814                                 inputs.reserve_exact(per_commitment_data.len());
 815
 816                                 for (idx, htlc) in per_commitment_data.iter().enumerate() {
 817                                         let expected_script = chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey);
 818                                         if htlc.transaction_output_index as usize >= tx.output.len() ||
 819                                                         tx.output[htlc.transaction_output_index as usize].value != htlc.amount_msat / 1000 ||
 820                                                         tx.output[htlc.transaction_output_index as usize].script_pubkey != expected_script.to_v0_p2wsh() {
 821                                                 return (txn_to_broadcast, (commitment_txid, watch_outputs)); // Corrupted per_commitment_data, fuck this user
 822                                         }
 823                                         let input = TxIn {
 824                                                 previous_output: BitcoinOutPoint {
 825                                                         txid: commitment_txid,
 826                                                         vout: htlc.transaction_output_index,
 827                                                 },
 828                                                 script_sig: Script::new(),
 829                                                 sequence: 0xfffffffd,
 830                                                 witness: Vec::new(),
 831                                         };
 832                                         if htlc.cltv_expiry > height + CLTV_SHARED_CLAIM_BUFFER {
 833                                                 inputs.push(input);
 834                                                 htlc_idxs.push(Some(idx));
 835                                                 values.push(tx.output[htlc.transaction_output_index as usize].value);
 836                                                 total_value += htlc.amount_msat / 1000;
 837                                         } else {
 838                                                 let mut single_htlc_tx = Transaction {
 839                                                         version: 2,
 840                                                         lock_time: 0,
 841                                                         input: vec![input],
 842                                                         output: vec!(TxOut {
 843                                                                 script_pubkey: self.destination_script.clone(),
 844                                                                 value: htlc.amount_msat / 1000, //TODO: - fee
 845                                                         }),
 846                                                 };
 847                                                 let sighash_parts = bip143::SighashComponents::new(&single_htlc_tx);
 848                                                 sign_input!(sighash_parts, single_htlc_tx.input[0], Some(idx), htlc.amount_msat / 1000);
 849                                                 txn_to_broadcast.push(single_htlc_tx); // TODO: This is not yet tested in ChannelManager!
 850                                         }
 851                                 }
 852                         }
 853
 854                         if !inputs.is_empty() || !txn_to_broadcast.is_empty() { // ie we're confident this is actually ours
 855                                 // We're definitely a remote commitment transaction!
 856                                 watch_outputs.append(&mut tx.output.clone());
 857                                 self.remote_commitment_txn_on_chain.lock().unwrap().insert(commitment_txid, commitment_number);
 858                         }
 859                         if inputs.is_empty() { return (txn_to_broadcast, (commitment_txid, watch_outputs)); } // Nothing to be done...probably a false positive/local tx
 860
 861                         let outputs = vec!(TxOut {
 862                                 script_pubkey: self.destination_script.clone(),
 863                                 value: total_value, //TODO: - fee
 864                         });
 865                         let mut spend_tx = Transaction {
 866                                 version: 2,
 867                                 lock_time: 0,
 868                                 input: inputs,
 869                                 output: outputs,
 870                         };
 871
 872                         let mut values_drain = values.drain(..);
 873                         let sighash_parts = bip143::SighashComponents::new(&spend_tx);
 874
 875                         for (input, htlc_idx) in spend_tx.input.iter_mut().zip(htlc_idxs.iter()) {
 876                                 let value = values_drain.next().unwrap();
 877                                 sign_input!(sighash_parts, input, htlc_idx, value);
 878                         }
 879
 880                         txn_to_broadcast.push(spend_tx);
 881                 } else if let Some(per_commitment_data) = per_commitment_option {
 882                         // While this isn't useful yet, there is a potential race where if a counterparty
 883                         // revokes a state at the same time as the commitment transaction for that state is
 884                         // confirmed, and the watchtower receives the block before the user, the user could
 885                         // upload a new ChannelMonitor with the revocation secret but the watchtower has
 886                         // already processed the block, resulting in the remote_commitment_txn_on_chain entry
 887                         // not being generated by the above conditional. Thus, to be safe, we go ahead and
 888                         // insert it here.
 889                         watch_outputs.append(&mut tx.output.clone());
 890                         self.remote_commitment_txn_on_chain.lock().unwrap().insert(commitment_txid, commitment_number);
 891
 892                         if let Some(revocation_points) = self.their_cur_revocation_points {
 893                                 let revocation_point_option =
 894                                         if revocation_points.0 == commitment_number { Some(&revocation_points.1) }
 895                                         else if let Some(point) = revocation_points.2.as_ref() {
 896                                                 if revocation_points.0 == commitment_number + 1 { Some(point) } else { None }
 897                                         } else { None };
 898                                 if let Some(revocation_point) = revocation_point_option {
 899                                         let (revocation_pubkey, b_htlc_key) = match self.key_storage {
 900                                                 KeyStorage::PrivMode { ref revocation_base_key, ref htlc_base_key } => {
 901                                                         (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, revocation_point, &PublicKey::from_secret_key(&self.secp_ctx, &revocation_base_key))),
 902                                                         ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &PublicKey::from_secret_key(&self.secp_ctx, &htlc_base_key))))
 903                                                 },
 904                                                 KeyStorage::SigsMode { ref revocation_base_key, ref htlc_base_key, .. } => {
 905                                                         (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, revocation_point, &revocation_base_key)),
 906                                                         ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &htlc_base_key)))
 907                                                 },
 908                                         };
 909                                         let a_htlc_key = match self.their_htlc_base_key {
 910                                                 None => return (txn_to_broadcast, (commitment_txid, watch_outputs)),
 911                                                 Some(their_htlc_base_key) => ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &their_htlc_base_key)),
 912                                         };
 913
 914                                         let mut total_value = 0;
 915                                         let mut values = Vec::new();
 916                                         let mut inputs = Vec::new();
 917
 918                                         macro_rules! sign_input {
 919                                                 ($sighash_parts: expr, $input: expr, $amount: expr, $preimage: expr) => {
 920                                                         {
 921                                                                 let (sig, redeemscript) = match self.key_storage {
 922                                                                         KeyStorage::PrivMode { ref htlc_base_key, .. } => {
 923                                                                                 let htlc = &per_commitment_option.unwrap()[$input.sequence as usize];
 924                                                                                 let redeemscript = chan_utils::get_htlc_redeemscript_with_explicit_keys(htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey);
 925                                                                                 let sighash = ignore_error!(Message::from_slice(&$sighash_parts.sighash_all(&$input, &redeemscript, $amount)[..]));
 926                                                                                 let htlc_key = ignore_error!(chan_utils::derive_private_key(&self.secp_ctx, revocation_point, &htlc_base_key));
 927                                                                                 (self.secp_ctx.sign(&sighash, &htlc_key), redeemscript)
 928                                                                         },
 929                                                                         KeyStorage::SigsMode { .. } => {
 930                                                                                 unimplemented!();
 931                                                                         }
 932                                                                 };
 933                                                                 $input.witness.push(sig.serialize_der(&self.secp_ctx).to_vec());
 934                                                                 $input.witness[0].push(SigHashType::All as u8);
 935                                                                 $input.witness.push($preimage);
 936                                                                 $input.witness.push(redeemscript.into_bytes());
 937                                                         }
 938                                                 }
 939                                         }
 940
 941                                         for (idx, htlc) in per_commitment_data.iter().enumerate() {
 942                                                 if let Some(payment_preimage) = self.payment_preimages.get(&htlc.payment_hash) {
 943                                                         let input = TxIn {
 944                                                                 previous_output: BitcoinOutPoint {
 945                                                                         txid: commitment_txid,
 946                                                                         vout: htlc.transaction_output_index,
 947                                                                 },
 948                                                                 script_sig: Script::new(),
 949                                                                 sequence: idx as u32, // reset to 0xfffffffd in sign_input
 950                                                                 witness: Vec::new(),
 951                                                         };
 952                                                         if htlc.cltv_expiry > height + CLTV_SHARED_CLAIM_BUFFER {
 953                                                                 inputs.push(input);
 954                                                                 values.push((tx.output[htlc.transaction_output_index as usize].value, payment_preimage));
 955                                                                 total_value += htlc.amount_msat / 1000;
 956                                                         } else {
 957                                                                 let mut single_htlc_tx = Transaction {
 958                                                                         version: 2,
 959                                                                         lock_time: 0,
 960                                                                         input: vec![input],
 961                                                                         output: vec!(TxOut {
 962                                                                                 script_pubkey: self.destination_script.clone(),
 963                                                                                 value: htlc.amount_msat / 1000, //TODO: - fee
 964                                                                         }),
 965                                                                 };
 966                                                                 let sighash_parts = bip143::SighashComponents::new(&single_htlc_tx);
 967                                                                 sign_input!(sighash_parts, single_htlc_tx.input[0], htlc.amount_msat / 1000, payment_preimage.to_vec());
 968                                                                 txn_to_broadcast.push(single_htlc_tx);
 969                                                         }
 970                                                 }
 971                                         }
 972
 973                                         if inputs.is_empty() { return (txn_to_broadcast, (commitment_txid, watch_outputs)); } // Nothing to be done...probably a false positive/local tx
 974
 975                                         let outputs = vec!(TxOut {
 976                                                 script_pubkey: self.destination_script.clone(),
 977                                                 value: total_value, //TODO: - fee
 978                                         });
 979                                         let mut spend_tx = Transaction {
 980                                                 version: 2,
 981                                                 lock_time: 0,
 982                                                 input: inputs,
 983                                                 output: outputs,
 984                                         };
 985
 986                                         let mut values_drain = values.drain(..);
 987                                         let sighash_parts = bip143::SighashComponents::new(&spend_tx);
 988
 989                                         for input in spend_tx.input.iter_mut() {
 990                                                 let value = values_drain.next().unwrap();
 991                                                 sign_input!(sighash_parts, input, value.0, value.1.to_vec());
 992                                         }
 993
 994                                         txn_to_broadcast.push(spend_tx);
 995                                 }
 996                         }
 997                 }
 998
 999                 (txn_to_broadcast, (commitment_txid, watch_outputs))
1000         }
1001
1002         /// Attempst to claim a remote HTLC-Success/HTLC-Timeout s outputs using the revocation key
1003         fn check_spend_remote_htlc(&self, tx: &Transaction, commitment_number: u64) -> Option<Transaction> {
1004                 let htlc_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
1005
1006                 macro_rules! ignore_error {
1007                         ( $thing : expr ) => {
1008                                 match $thing {
1009                                         Ok(a) => a,
1010                                         Err(_) => return None
1011                                 }
1012                         };
1013                 }
1014
1015                 let secret = ignore_error!(self.get_secret(commitment_number));
1016                 let per_commitment_key = ignore_error!(SecretKey::from_slice(&self.secp_ctx, &secret));
1017                 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1018                 let revocation_pubkey = match self.key_storage {
1019                         KeyStorage::PrivMode { ref revocation_base_key, .. } => {
1020                                 ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &PublicKey::from_secret_key(&self.secp_ctx, &revocation_base_key)))
1021                         },
1022                         KeyStorage::SigsMode { ref revocation_base_key, .. } => {
1023                                 ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &revocation_base_key))
1024                         },
1025                 };
1026                 let delayed_key = match self.their_delayed_payment_base_key {
1027                         None => return None,
1028                         Some(their_delayed_payment_base_key) => ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &their_delayed_payment_base_key)),
1029                 };
1030                 let redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.their_to_self_delay.unwrap(), &delayed_key);
1031                 let revokeable_p2wsh = redeemscript.to_v0_p2wsh();
1032
1033                 let mut inputs = Vec::new();
1034                 let mut amount = 0;
1035
1036                 if tx.output[0].script_pubkey == revokeable_p2wsh { //HTLC transactions have one txin, one txout
1037                         inputs.push(TxIn {
1038                                 previous_output: BitcoinOutPoint {
1039                                         txid: htlc_txid,
1040                                         vout: 0,
1041                                 },
1042                                 script_sig: Script::new(),
1043                                 sequence: 0xfffffffd,
1044                                 witness: Vec::new(),
1045                         });
1046                         amount = tx.output[0].value;
1047                 }
1048
1049                 if !inputs.is_empty() {
1050                         let outputs = vec!(TxOut {
1051                                 script_pubkey: self.destination_script.clone(),
1052                                 value: amount, //TODO: - fee
1053                         });
1054
1055                         let mut spend_tx = Transaction {
1056                                 version: 2,
1057                                 lock_time: 0,
1058                                 input: inputs,
1059                                 output: outputs,
1060                         };
1061
1062                         let sighash_parts = bip143::SighashComponents::new(&spend_tx);
1063
1064                         let sig = match self.key_storage {
1065                                 KeyStorage::PrivMode { ref revocation_base_key, .. } => {
1066                                         let sighash = ignore_error!(Message::from_slice(&sighash_parts.sighash_all(&spend_tx.input[0], &redeemscript, amount)[..]));
1067                                         let revocation_key = ignore_error!(chan_utils::derive_private_revocation_key(&self.secp_ctx, &per_commitment_key, &revocation_base_key));
1068                                         self.secp_ctx.sign(&sighash, &revocation_key)
1069                                 }
1070                                 KeyStorage::SigsMode { .. } => {
1071                                         unimplemented!();
1072                                 }
1073                         };
1074                         spend_tx.input[0].witness.push(sig.serialize_der(&self.secp_ctx).to_vec());
1075                         spend_tx.input[0].witness[0].push(SigHashType::All as u8);
1076                         spend_tx.input[0].witness.push(vec!(1));
1077                         spend_tx.input[0].witness.push(redeemscript.into_bytes());
1078
1079                         Some(spend_tx)
1080                 } else { None }
1081         }
1082
1083         fn broadcast_by_local_state(&self, local_tx: &LocalSignedTx) -> Vec<Transaction> {
1084                 let mut res = Vec::with_capacity(local_tx.htlc_outputs.len());
1085
1086                 for &(ref htlc, ref their_sig, ref our_sig) in local_tx.htlc_outputs.iter() {
1087                         if htlc.offered {
1088                                 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);
1089
1090                                 htlc_timeout_tx.input[0].witness.push(Vec::new()); // First is the multisig dummy
1091
1092                                 htlc_timeout_tx.input[0].witness.push(their_sig.serialize_der(&self.secp_ctx).to_vec());
1093                                 htlc_timeout_tx.input[0].witness[1].push(SigHashType::All as u8);
1094                                 htlc_timeout_tx.input[0].witness.push(our_sig.serialize_der(&self.secp_ctx).to_vec());
1095                                 htlc_timeout_tx.input[0].witness[2].push(SigHashType::All as u8);
1096
1097                                 htlc_timeout_tx.input[0].witness.push(Vec::new());
1098                                 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());
1099
1100                                 res.push(htlc_timeout_tx);
1101                         } else {
1102                                 if let Some(payment_preimage) = self.payment_preimages.get(&htlc.payment_hash) {
1103                                         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);
1104
1105                                         htlc_success_tx.input[0].witness.push(Vec::new()); // First is the multisig dummy
1106
1107                                         htlc_success_tx.input[0].witness.push(their_sig.serialize_der(&self.secp_ctx).to_vec());
1108                                         htlc_success_tx.input[0].witness[1].push(SigHashType::All as u8);
1109                                         htlc_success_tx.input[0].witness.push(our_sig.serialize_der(&self.secp_ctx).to_vec());
1110                                         htlc_success_tx.input[0].witness[2].push(SigHashType::All as u8);
1111
1112                                         htlc_success_tx.input[0].witness.push(payment_preimage.to_vec());
1113                                         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());
1114
1115                                         res.push(htlc_success_tx);
1116                                 }
1117                         }
1118                 }
1119
1120                 res
1121         }
1122
1123         /// Attempts to claim any claimable HTLCs in a commitment transaction which was not (yet)
1124         /// revoked using data in local_claimable_outpoints.
1125         /// Should not be used if check_spend_revoked_transaction succeeds.
1126         fn check_spend_local_transaction(&self, tx: &Transaction, _height: u32) -> Vec<Transaction> {
1127                 let commitment_txid = tx.txid();
1128                 if let &Some(ref local_tx) = &self.current_local_signed_commitment_tx {
1129                         if local_tx.txid == commitment_txid {
1130                                 return self.broadcast_by_local_state(local_tx);
1131                         }
1132                 }
1133                 if let &Some(ref local_tx) = &self.prev_local_signed_commitment_tx {
1134                         if local_tx.txid == commitment_txid {
1135                                 return self.broadcast_by_local_state(local_tx);
1136                         }
1137                 }
1138                 Vec::new()
1139         }
1140
1141         fn block_connected(&self, txn_matched: &[&Transaction], height: u32, broadcaster: &BroadcasterInterface)-> Vec<(Sha256dHash, Vec<TxOut>)> {
1142                 let mut watch_outputs = Vec::new();
1143                 for tx in txn_matched {
1144                         if tx.input.len() == 1 {
1145                                 // Assuming our keys were not leaked (in which case we're screwed no matter what),
1146                                 // commitment transactions and HTLC transactions will all only ever have one input,
1147                                 // which is an easy way to filter out any potential non-matching txn for lazy
1148                                 // filters.
1149                                 let prevout = &tx.input[0].previous_output;
1150                                 let mut txn: Vec<Transaction> = Vec::new();
1151                                 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) {
1152                                         let (remote_txn, new_outputs) = self.check_spend_remote_transaction(tx, height);
1153                                         txn = remote_txn;
1154                                         if !new_outputs.1.is_empty() {
1155                                                 watch_outputs.push(new_outputs);
1156                                         }
1157                                         if txn.is_empty() {
1158                                                 txn = self.check_spend_local_transaction(tx, height);
1159                                         }
1160                                 } else {
1161                                         let remote_commitment_txn_on_chain = self.remote_commitment_txn_on_chain.lock().unwrap();
1162                                         if let Some(commitment_number) = remote_commitment_txn_on_chain.get(&prevout.txid) {
1163                                                 if let Some(tx) = self.check_spend_remote_htlc(tx, *commitment_number) {
1164                                                         txn.push(tx);
1165                                                 }
1166                                         }
1167                                 }
1168                                 for tx in txn.iter() {
1169                                         broadcaster.broadcast_transaction(tx);
1170                                 }
1171                         }
1172                 }
1173                 if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
1174                         let mut needs_broadcast = false;
1175                         for &(ref htlc, _, _) in cur_local_tx.htlc_outputs.iter() {
1176                                 if htlc.cltv_expiry <= height + CLTV_CLAIM_BUFFER {
1177                                         if htlc.offered || self.payment_preimages.contains_key(&htlc.payment_hash) {
1178                                                 needs_broadcast = true;
1179                                         }
1180                                 }
1181                         }
1182
1183                         if needs_broadcast {
1184                                 broadcaster.broadcast_transaction(&cur_local_tx.tx);
1185                                 for tx in self.broadcast_by_local_state(&cur_local_tx) {
1186                                         broadcaster.broadcast_transaction(&tx);
1187                                 }
1188                         }
1189                 }
1190                 watch_outputs
1191         }
1192
1193         pub(super) fn would_broadcast_at_height(&self, height: u32) -> bool {
1194                 if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
1195                         for &(ref htlc, _, _) in cur_local_tx.htlc_outputs.iter() {
1196                                 if htlc.cltv_expiry <= height + CLTV_CLAIM_BUFFER {
1197                                         if htlc.offered || self.payment_preimages.contains_key(&htlc.payment_hash) {
1198                                                 return true;
1199                                         }
1200                                 }
1201                         }
1202                 }
1203                 false
1204         }
1205 }
1206
1207 impl<R: ::std::io::Read> Readable<R> for ChannelMonitor {
1208         fn read(reader: &mut R) -> Result<Self, DecodeError> {
1209                 // TODO: read_to_end and then deserializing from that vector is really dumb, we should
1210                 // actually use the fancy serialization framework we have instead of hacking around it.
1211                 let mut datavec = Vec::new();
1212                 reader.read_to_end(&mut datavec)?;
1213                 let data = &datavec;
1214
1215                 let mut read_pos = 0;
1216                 macro_rules! read_bytes {
1217                         ($byte_count: expr) => {
1218                                 {
1219                                         if ($byte_count as usize) > data.len() - read_pos {
1220                                                 return Err(DecodeError::ShortRead);
1221                                         }
1222                                         read_pos += $byte_count as usize;
1223                                         &data[read_pos - $byte_count as usize..read_pos]
1224                                 }
1225                         }
1226                 }
1227
1228                 let secp_ctx = Secp256k1::new();
1229                 macro_rules! unwrap_obj {
1230                         ($key: expr) => {
1231                                 match $key {
1232                                         Ok(res) => res,
1233                                         Err(_) => return Err(DecodeError::InvalidValue),
1234                                 }
1235                         }
1236                 }
1237
1238                 let _ver = read_bytes!(1)[0];
1239                 let min_ver = read_bytes!(1)[0];
1240                 if min_ver > SERIALIZATION_VERSION {
1241                         return Err(DecodeError::UnknownVersion);
1242                 }
1243
1244                 // Technically this can fail and serialize fail a round-trip, but only for serialization of
1245                 // barely-init'd ChannelMonitors that we can't do anything with.
1246                 let outpoint = OutPoint {
1247                         txid: Sha256dHash::from(read_bytes!(32)),
1248                         index: byte_utils::slice_to_be16(read_bytes!(2)),
1249                 };
1250                 let script_len = byte_utils::slice_to_be64(read_bytes!(8));
1251                 let funding_txo = Some((outpoint, Script::from(read_bytes!(script_len).to_vec())));
1252                 let commitment_transaction_number_obscure_factor = byte_utils::slice_to_be48(read_bytes!(6));
1253
1254                 let key_storage = match read_bytes!(1)[0] {
1255                         0 => {
1256                                 KeyStorage::PrivMode {
1257                                         revocation_base_key: unwrap_obj!(SecretKey::from_slice(&secp_ctx, read_bytes!(32))),
1258                                         htlc_base_key: unwrap_obj!(SecretKey::from_slice(&secp_ctx, read_bytes!(32))),
1259                                 }
1260                         },
1261                         _ => return Err(DecodeError::InvalidValue),
1262                 };
1263
1264                 let delayed_payment_base_key = unwrap_obj!(PublicKey::from_slice(&secp_ctx, read_bytes!(33)));
1265                 let their_htlc_base_key = Some(unwrap_obj!(PublicKey::from_slice(&secp_ctx, read_bytes!(33))));
1266                 let their_delayed_payment_base_key = Some(unwrap_obj!(PublicKey::from_slice(&secp_ctx, read_bytes!(33))));
1267
1268                 let their_cur_revocation_points = {
1269                         let first_idx = byte_utils::slice_to_be48(read_bytes!(6));
1270                         if first_idx == 0 {
1271                                 None
1272                         } else {
1273                                 let first_point = unwrap_obj!(PublicKey::from_slice(&secp_ctx, read_bytes!(33)));
1274                                 let second_point_slice = read_bytes!(33);
1275                                 if second_point_slice[0..32] == [0; 32] && second_point_slice[32] == 0 {
1276                                         Some((first_idx, first_point, None))
1277                                 } else {
1278                                         Some((first_idx, first_point, Some(unwrap_obj!(PublicKey::from_slice(&secp_ctx, second_point_slice)))))
1279                                 }
1280                         }
1281                 };
1282
1283                 let our_to_self_delay = byte_utils::slice_to_be16(read_bytes!(2));
1284                 let their_to_self_delay = Some(byte_utils::slice_to_be16(read_bytes!(2)));
1285
1286                 let mut old_secrets = [([0; 32], 1 << 48); 49];
1287                 for &mut (ref mut secret, ref mut idx) in old_secrets.iter_mut() {
1288                         secret.copy_from_slice(read_bytes!(32));
1289                         *idx = byte_utils::slice_to_be64(read_bytes!(8));
1290                 }
1291
1292                 macro_rules! read_htlc_in_commitment {
1293                         () => {
1294                                 {
1295                                         let offered = match read_bytes!(1)[0] {
1296                                                 0 => false, 1 => true,
1297                                                 _ => return Err(DecodeError::InvalidValue),
1298                                         };
1299                                         let amount_msat = byte_utils::slice_to_be64(read_bytes!(8));
1300                                         let cltv_expiry = byte_utils::slice_to_be32(read_bytes!(4));
1301                                         let mut payment_hash = [0; 32];
1302                                         payment_hash[..].copy_from_slice(read_bytes!(32));
1303                                         let transaction_output_index = byte_utils::slice_to_be32(read_bytes!(4));
1304
1305                                         HTLCOutputInCommitment {
1306                                                 offered, amount_msat, cltv_expiry, payment_hash, transaction_output_index
1307                                         }
1308                                 }
1309                         }
1310                 }
1311
1312                 let remote_claimable_outpoints_len = byte_utils::slice_to_be64(read_bytes!(8));
1313                 if remote_claimable_outpoints_len > data.len() as u64 / 64 { return Err(DecodeError::BadLengthDescriptor); }
1314                 let mut remote_claimable_outpoints = HashMap::with_capacity(remote_claimable_outpoints_len as usize);
1315                 for _ in 0..remote_claimable_outpoints_len {
1316                         let txid = Sha256dHash::from(read_bytes!(32));
1317                         let outputs_count = byte_utils::slice_to_be64(read_bytes!(8));
1318                         if outputs_count > data.len() as u64 / 32 { return Err(DecodeError::BadLengthDescriptor); }
1319                         let mut outputs = Vec::with_capacity(outputs_count as usize);
1320                         for _ in 0..outputs_count {
1321                                 outputs.push(read_htlc_in_commitment!());
1322                         }
1323                         if let Some(_) = remote_claimable_outpoints.insert(txid, outputs) {
1324                                 return Err(DecodeError::InvalidValue);
1325                         }
1326                 }
1327
1328                 let remote_commitment_txn_on_chain_len = byte_utils::slice_to_be64(read_bytes!(8));
1329                 if remote_commitment_txn_on_chain_len > data.len() as u64 / 32 { return Err(DecodeError::BadLengthDescriptor); }
1330                 let mut remote_commitment_txn_on_chain = HashMap::with_capacity(remote_commitment_txn_on_chain_len as usize);
1331                 for _ in 0..remote_commitment_txn_on_chain_len {
1332                         let txid = Sha256dHash::from(read_bytes!(32));
1333                         let commitment_number = byte_utils::slice_to_be48(read_bytes!(6));
1334                         if let Some(_) = remote_commitment_txn_on_chain.insert(txid, commitment_number) {
1335                                 return Err(DecodeError::InvalidValue);
1336                         }
1337                 }
1338
1339                 let remote_hash_commitment_number_len = byte_utils::slice_to_be64(read_bytes!(8));
1340                 if remote_hash_commitment_number_len > data.len() as u64 / 32 { return Err(DecodeError::BadLengthDescriptor); }
1341                 let mut remote_hash_commitment_number = HashMap::with_capacity(remote_hash_commitment_number_len as usize);
1342                 for _ in 0..remote_hash_commitment_number_len {
1343                         let mut txid = [0; 32];
1344                         txid[..].copy_from_slice(read_bytes!(32));
1345                         let commitment_number = byte_utils::slice_to_be48(read_bytes!(6));
1346                         if let Some(_) = remote_hash_commitment_number.insert(txid, commitment_number) {
1347                                 return Err(DecodeError::InvalidValue);
1348                         }
1349                 }
1350
1351                 macro_rules! read_local_tx {
1352                         () => {
1353                                 {
1354                                         let tx_len = byte_utils::slice_to_be64(read_bytes!(8));
1355                                         let tx_ser = read_bytes!(tx_len);
1356                                         let tx: Transaction = unwrap_obj!(serialize::deserialize(tx_ser));
1357                                         if serialize::serialize(&tx).unwrap() != tx_ser {
1358                                                 // We check that the tx re-serializes to the same form to ensure there is
1359                                                 // no extra data, and as rust-bitcoin doesn't handle the 0-input ambiguity
1360                                                 // all that well.
1361                                                 return Err(DecodeError::InvalidValue);
1362                                         }
1363
1364                                         let revocation_key = unwrap_obj!(PublicKey::from_slice(&secp_ctx, read_bytes!(33)));
1365                                         let a_htlc_key = unwrap_obj!(PublicKey::from_slice(&secp_ctx, read_bytes!(33)));
1366                                         let b_htlc_key = unwrap_obj!(PublicKey::from_slice(&secp_ctx, read_bytes!(33)));
1367                                         let delayed_payment_key = unwrap_obj!(PublicKey::from_slice(&secp_ctx, read_bytes!(33)));
1368                                         let feerate_per_kw = byte_utils::slice_to_be64(read_bytes!(8));
1369
1370                                         let htlc_outputs_len = byte_utils::slice_to_be64(read_bytes!(8));
1371                                         if htlc_outputs_len > data.len() as u64 / 128 { return Err(DecodeError::BadLengthDescriptor); }
1372                                         let mut htlc_outputs = Vec::with_capacity(htlc_outputs_len as usize);
1373                                         for _ in 0..htlc_outputs_len {
1374                                                 htlc_outputs.push((read_htlc_in_commitment!(),
1375                                                                 unwrap_obj!(Signature::from_compact(&secp_ctx, read_bytes!(64))),
1376                                                                 unwrap_obj!(Signature::from_compact(&secp_ctx, read_bytes!(64)))));
1377                                         }
1378
1379                                         LocalSignedTx {
1380                                                 txid: tx.txid(),
1381                                                 tx, revocation_key, a_htlc_key, b_htlc_key, delayed_payment_key, feerate_per_kw, htlc_outputs
1382                                         }
1383                                 }
1384                         }
1385                 }
1386
1387                 let prev_local_signed_commitment_tx = match read_bytes!(1)[0] {
1388                         0 => None,
1389                         1 => {
1390                                 Some(read_local_tx!())
1391                         },
1392                         _ => return Err(DecodeError::InvalidValue),
1393                 };
1394
1395                 let current_local_signed_commitment_tx = match read_bytes!(1)[0] {
1396                         0 => None,
1397                         1 => {
1398                                 Some(read_local_tx!())
1399                         },
1400                         _ => return Err(DecodeError::InvalidValue),
1401                 };
1402
1403                 let payment_preimages_len = byte_utils::slice_to_be64(read_bytes!(8));
1404                 if payment_preimages_len > data.len() as u64 / 32 { return Err(DecodeError::InvalidValue); }
1405                 let mut payment_preimages = HashMap::with_capacity(payment_preimages_len as usize);
1406                 let mut sha = Sha256::new();
1407                 for _ in 0..payment_preimages_len {
1408                         let mut preimage = [0; 32];
1409                         preimage[..].copy_from_slice(read_bytes!(32));
1410                         sha.reset();
1411                         sha.input(&preimage);
1412                         let mut hash = [0; 32];
1413                         sha.result(&mut hash);
1414                         if let Some(_) = payment_preimages.insert(hash, preimage) {
1415                                 return Err(DecodeError::InvalidValue);
1416                         }
1417                 }
1418
1419                 let destination_script_len = byte_utils::slice_to_be64(read_bytes!(8));
1420                 let destination_script = Script::from(read_bytes!(destination_script_len).to_vec());
1421
1422                 Ok(ChannelMonitor {
1423                         funding_txo,
1424                         commitment_transaction_number_obscure_factor,
1425
1426                         key_storage,
1427                         delayed_payment_base_key,
1428                         their_htlc_base_key,
1429                         their_delayed_payment_base_key,
1430                         their_cur_revocation_points,
1431
1432                         our_to_self_delay,
1433                         their_to_self_delay,
1434
1435                         old_secrets,
1436                         remote_claimable_outpoints,
1437                         remote_commitment_txn_on_chain: Mutex::new(remote_commitment_txn_on_chain),
1438                         remote_hash_commitment_number,
1439
1440                         prev_local_signed_commitment_tx,
1441                         current_local_signed_commitment_tx,
1442
1443                         payment_preimages,
1444
1445                         destination_script,
1446                         secp_ctx,
1447                 })
1448         }
1449
1450 }
1451
1452 #[cfg(test)]
1453 mod tests {
1454         use bitcoin::blockdata::script::Script;
1455         use bitcoin::blockdata::transaction::Transaction;
1456         use crypto::digest::Digest;
1457         use hex;
1458         use ln::channelmonitor::ChannelMonitor;
1459         use ln::chan_utils::{HTLCOutputInCommitment, TxCreationKeys};
1460         use util::sha2::Sha256;
1461         use secp256k1::key::{SecretKey,PublicKey};
1462         use secp256k1::{Secp256k1, Signature};
1463         use rand::{thread_rng,Rng};
1464
1465         #[test]
1466         fn test_per_commitment_storage() {
1467                 // Test vectors from BOLT 3:
1468                 let mut secrets: Vec<[u8; 32]> = Vec::new();
1469                 let mut monitor: ChannelMonitor;
1470                 let secp_ctx = Secp256k1::new();
1471
1472                 macro_rules! test_secrets {
1473                         () => {
1474                                 let mut idx = 281474976710655;
1475                                 for secret in secrets.iter() {
1476                                         assert_eq!(monitor.get_secret(idx).unwrap(), *secret);
1477                                         idx -= 1;
1478                                 }
1479                                 assert_eq!(monitor.get_min_seen_secret(), idx + 1);
1480                                 assert!(monitor.get_secret(idx).is_err());
1481                         };
1482                 }
1483
1484                 let delayed_payment_base_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap());
1485
1486                 {
1487                         // insert_secret correct sequence
1488                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &delayed_payment_base_key, &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), 0, Script::new());
1489                         secrets.clear();
1490
1491                         secrets.push([0; 32]);
1492                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1493                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone(), None).unwrap();
1494                         test_secrets!();
1495
1496                         secrets.push([0; 32]);
1497                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1498                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone(), None).unwrap();
1499                         test_secrets!();
1500
1501                         secrets.push([0; 32]);
1502                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1503                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone(), None).unwrap();
1504                         test_secrets!();
1505
1506                         secrets.push([0; 32]);
1507                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1508                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone(), None).unwrap();
1509                         test_secrets!();
1510
1511                         secrets.push([0; 32]);
1512                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
1513                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone(), None).unwrap();
1514                         test_secrets!();
1515
1516                         secrets.push([0; 32]);
1517                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
1518                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone(), None).unwrap();
1519                         test_secrets!();
1520
1521                         secrets.push([0; 32]);
1522                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
1523                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone(), None).unwrap();
1524                         test_secrets!();
1525
1526                         secrets.push([0; 32]);
1527                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
1528                         monitor.provide_secret(281474976710648, secrets.last().unwrap().clone(), None).unwrap();
1529                         test_secrets!();
1530                 }
1531
1532                 {
1533                         // insert_secret #1 incorrect
1534                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &delayed_payment_base_key, &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), 0, Script::new());
1535                         secrets.clear();
1536
1537                         secrets.push([0; 32]);
1538                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
1539                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone(), None).unwrap();
1540                         test_secrets!();
1541
1542                         secrets.push([0; 32]);
1543                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1544                         assert_eq!(monitor.provide_secret(281474976710654, secrets.last().unwrap().clone(), None).unwrap_err().err,
1545                                         "Previous secret did not match new one");
1546                 }
1547
1548                 {
1549                         // insert_secret #2 incorrect (#1 derived from incorrect)
1550                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &delayed_payment_base_key, &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), 0, Script::new());
1551                         secrets.clear();
1552
1553                         secrets.push([0; 32]);
1554                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
1555                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone(), None).unwrap();
1556                         test_secrets!();
1557
1558                         secrets.push([0; 32]);
1559                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("dddc3a8d14fddf2b68fa8c7fbad2748274937479dd0f8930d5ebb4ab6bd866a3").unwrap());
1560                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone(), None).unwrap();
1561                         test_secrets!();
1562
1563                         secrets.push([0; 32]);
1564                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1565                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone(), None).unwrap();
1566                         test_secrets!();
1567
1568                         secrets.push([0; 32]);
1569                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1570                         assert_eq!(monitor.provide_secret(281474976710652, secrets.last().unwrap().clone(), None).unwrap_err().err,
1571                                         "Previous secret did not match new one");
1572                 }
1573
1574                 {
1575                         // insert_secret #3 incorrect
1576                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &delayed_payment_base_key, &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), 0, Script::new());
1577                         secrets.clear();
1578
1579                         secrets.push([0; 32]);
1580                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1581                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone(), None).unwrap();
1582                         test_secrets!();
1583
1584                         secrets.push([0; 32]);
1585                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1586                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone(), None).unwrap();
1587                         test_secrets!();
1588
1589                         secrets.push([0; 32]);
1590                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c51a18b13e8527e579ec56365482c62f180b7d5760b46e9477dae59e87ed423a").unwrap());
1591                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone(), None).unwrap();
1592                         test_secrets!();
1593
1594                         secrets.push([0; 32]);
1595                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1596                         assert_eq!(monitor.provide_secret(281474976710652, secrets.last().unwrap().clone(), None).unwrap_err().err,
1597                                         "Previous secret did not match new one");
1598                 }
1599
1600                 {
1601                         // insert_secret #4 incorrect (1,2,3 derived from incorrect)
1602                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &delayed_payment_base_key, &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), 0, Script::new());
1603                         secrets.clear();
1604
1605                         secrets.push([0; 32]);
1606                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
1607                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone(), None).unwrap();
1608                         test_secrets!();
1609
1610                         secrets.push([0; 32]);
1611                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("dddc3a8d14fddf2b68fa8c7fbad2748274937479dd0f8930d5ebb4ab6bd866a3").unwrap());
1612                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone(), None).unwrap();
1613                         test_secrets!();
1614
1615                         secrets.push([0; 32]);
1616                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c51a18b13e8527e579ec56365482c62f180b7d5760b46e9477dae59e87ed423a").unwrap());
1617                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone(), None).unwrap();
1618                         test_secrets!();
1619
1620                         secrets.push([0; 32]);
1621                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("ba65d7b0ef55a3ba300d4e87af29868f394f8f138d78a7011669c79b37b936f4").unwrap());
1622                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone(), None).unwrap();
1623                         test_secrets!();
1624
1625                         secrets.push([0; 32]);
1626                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
1627                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone(), None).unwrap();
1628                         test_secrets!();
1629
1630                         secrets.push([0; 32]);
1631                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
1632                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone(), None).unwrap();
1633                         test_secrets!();
1634
1635                         secrets.push([0; 32]);
1636                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
1637                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone(), None).unwrap();
1638                         test_secrets!();
1639
1640                         secrets.push([0; 32]);
1641                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
1642                         assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone(), None).unwrap_err().err,
1643                                         "Previous secret did not match new one");
1644                 }
1645
1646                 {
1647                         // insert_secret #5 incorrect
1648                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &delayed_payment_base_key, &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), 0, Script::new());
1649                         secrets.clear();
1650
1651                         secrets.push([0; 32]);
1652                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1653                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone(), None).unwrap();
1654                         test_secrets!();
1655
1656                         secrets.push([0; 32]);
1657                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1658                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone(), None).unwrap();
1659                         test_secrets!();
1660
1661                         secrets.push([0; 32]);
1662                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1663                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone(), None).unwrap();
1664                         test_secrets!();
1665
1666                         secrets.push([0; 32]);
1667                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1668                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone(), None).unwrap();
1669                         test_secrets!();
1670
1671                         secrets.push([0; 32]);
1672                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("631373ad5f9ef654bb3dade742d09504c567edd24320d2fcd68e3cc47e2ff6a6").unwrap());
1673                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone(), None).unwrap();
1674                         test_secrets!();
1675
1676                         secrets.push([0; 32]);
1677                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
1678                         assert_eq!(monitor.provide_secret(281474976710650, secrets.last().unwrap().clone(), None).unwrap_err().err,
1679                                         "Previous secret did not match new one");
1680                 }
1681
1682                 {
1683                         // insert_secret #6 incorrect (5 derived from incorrect)
1684                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &delayed_payment_base_key, &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), 0, Script::new());
1685                         secrets.clear();
1686
1687                         secrets.push([0; 32]);
1688                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1689                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone(), None).unwrap();
1690                         test_secrets!();
1691
1692                         secrets.push([0; 32]);
1693                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1694                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone(), None).unwrap();
1695                         test_secrets!();
1696
1697                         secrets.push([0; 32]);
1698                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1699                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone(), None).unwrap();
1700                         test_secrets!();
1701
1702                         secrets.push([0; 32]);
1703                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1704                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone(), None).unwrap();
1705                         test_secrets!();
1706
1707                         secrets.push([0; 32]);
1708                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("631373ad5f9ef654bb3dade742d09504c567edd24320d2fcd68e3cc47e2ff6a6").unwrap());
1709                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone(), None).unwrap();
1710                         test_secrets!();
1711
1712                         secrets.push([0; 32]);
1713                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("b7e76a83668bde38b373970155c868a653304308f9896692f904a23731224bb1").unwrap());
1714                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone(), None).unwrap();
1715                         test_secrets!();
1716
1717                         secrets.push([0; 32]);
1718                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
1719                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone(), None).unwrap();
1720                         test_secrets!();
1721
1722                         secrets.push([0; 32]);
1723                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
1724                         assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone(), None).unwrap_err().err,
1725                                         "Previous secret did not match new one");
1726                 }
1727
1728                 {
1729                         // insert_secret #7 incorrect
1730                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &delayed_payment_base_key, &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), 0, Script::new());
1731                         secrets.clear();
1732
1733                         secrets.push([0; 32]);
1734                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1735                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone(), None).unwrap();
1736                         test_secrets!();
1737
1738                         secrets.push([0; 32]);
1739                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1740                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone(), None).unwrap();
1741                         test_secrets!();
1742
1743                         secrets.push([0; 32]);
1744                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1745                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone(), None).unwrap();
1746                         test_secrets!();
1747
1748                         secrets.push([0; 32]);
1749                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1750                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone(), None).unwrap();
1751                         test_secrets!();
1752
1753                         secrets.push([0; 32]);
1754                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
1755                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone(), None).unwrap();
1756                         test_secrets!();
1757
1758                         secrets.push([0; 32]);
1759                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
1760                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone(), None).unwrap();
1761                         test_secrets!();
1762
1763                         secrets.push([0; 32]);
1764                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("e7971de736e01da8ed58b94c2fc216cb1dca9e326f3a96e7194fe8ea8af6c0a3").unwrap());
1765                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone(), None).unwrap();
1766                         test_secrets!();
1767
1768                         secrets.push([0; 32]);
1769                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
1770                         assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone(), None).unwrap_err().err,
1771                                         "Previous secret did not match new one");
1772                 }
1773
1774                 {
1775                         // insert_secret #8 incorrect
1776                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &delayed_payment_base_key, &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), 0, Script::new());
1777                         secrets.clear();
1778
1779                         secrets.push([0; 32]);
1780                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1781                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone(), None).unwrap();
1782                         test_secrets!();
1783
1784                         secrets.push([0; 32]);
1785                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1786                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone(), None).unwrap();
1787                         test_secrets!();
1788
1789                         secrets.push([0; 32]);
1790                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1791                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone(), None).unwrap();
1792                         test_secrets!();
1793
1794                         secrets.push([0; 32]);
1795                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1796                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone(), None).unwrap();
1797                         test_secrets!();
1798
1799                         secrets.push([0; 32]);
1800                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
1801                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone(), None).unwrap();
1802                         test_secrets!();
1803
1804                         secrets.push([0; 32]);
1805                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
1806                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone(), None).unwrap();
1807                         test_secrets!();
1808
1809                         secrets.push([0; 32]);
1810                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
1811                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone(), None).unwrap();
1812                         test_secrets!();
1813
1814                         secrets.push([0; 32]);
1815                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a7efbc61aac46d34f77778bac22c8a20c6a46ca460addc49009bda875ec88fa4").unwrap());
1816                         assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone(), None).unwrap_err().err,
1817                                         "Previous secret did not match new one");
1818                 }
1819         }
1820
1821         #[test]
1822         fn test_prune_preimages() {
1823                 let secp_ctx = Secp256k1::new();
1824                 let dummy_sig = Signature::from_der(&secp_ctx, &hex::decode("3045022100fa86fa9a36a8cd6a7bb8f06a541787d51371d067951a9461d5404de6b928782e02201c8b7c334c10aed8976a3a465be9a28abff4cb23acbf00022295b378ce1fa3cd").unwrap()[..]).unwrap();
1825
1826                 macro_rules! dummy_keys {
1827                         () => {
1828                                 {
1829                                         let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap());
1830                                         TxCreationKeys {
1831                                                 per_commitment_point: dummy_key.clone(),
1832                                                 revocation_key: dummy_key.clone(),
1833                                                 a_htlc_key: dummy_key.clone(),
1834                                                 b_htlc_key: dummy_key.clone(),
1835                                                 a_delayed_payment_key: dummy_key.clone(),
1836                                                 b_payment_key: dummy_key.clone(),
1837                                         }
1838                                 }
1839                         }
1840                 }
1841                 let dummy_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
1842
1843                 let mut preimages = Vec::new();
1844                 {
1845                         let mut rng  = thread_rng();
1846                         for _ in 0..20 {
1847                                 let mut preimage = [0; 32];
1848                                 rng.fill_bytes(&mut preimage);
1849                                 let mut sha = Sha256::new();
1850                                 sha.input(&preimage);
1851                                 let mut hash = [0; 32];
1852                                 sha.result(&mut hash);
1853                                 preimages.push((preimage, hash));
1854                         }
1855                 }
1856
1857                 macro_rules! preimages_slice_to_htlc_outputs {
1858                         ($preimages_slice: expr) => {
1859                                 {
1860                                         let mut res = Vec::new();
1861                                         for (idx, preimage) in $preimages_slice.iter().enumerate() {
1862                                                 res.push(HTLCOutputInCommitment {
1863                                                         offered: true,
1864                                                         amount_msat: 0,
1865                                                         cltv_expiry: 0,
1866                                                         payment_hash: preimage.1.clone(),
1867                                                         transaction_output_index: idx as u32,
1868                                                 });
1869                                         }
1870                                         res
1871                                 }
1872                         }
1873                 }
1874                 macro_rules! preimages_to_local_htlcs {
1875                         ($preimages_slice: expr) => {
1876                                 {
1877                                         let mut inp = preimages_slice_to_htlc_outputs!($preimages_slice);
1878                                         let res: Vec<_> = inp.drain(..).map(|e| { (e, dummy_sig.clone(), dummy_sig.clone()) }).collect();
1879                                         res
1880                                 }
1881                         }
1882                 }
1883
1884                 macro_rules! test_preimages_exist {
1885                         ($preimages_slice: expr, $monitor: expr) => {
1886                                 for preimage in $preimages_slice {
1887                                         assert!($monitor.payment_preimages.contains_key(&preimage.1));
1888                                 }
1889                         }
1890                 }
1891
1892                 // Prune with one old state and a local commitment tx holding a few overlaps with the
1893                 // old state.
1894                 let delayed_payment_base_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap());
1895                 let mut monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &delayed_payment_base_key, &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), 0, Script::new());
1896                 monitor.set_their_to_self_delay(10);
1897
1898                 monitor.provide_latest_local_commitment_tx_info(dummy_tx.clone(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..10]));
1899                 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[5..15]), 281474976710655);
1900                 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[15..20]), 281474976710654);
1901                 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[17..20]), 281474976710653);
1902                 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[18..20]), 281474976710652);
1903                 for &(ref preimage, ref hash) in preimages.iter() {
1904                         monitor.provide_payment_preimage(hash, preimage);
1905                 }
1906
1907                 // Now provide a secret, pruning preimages 10-15
1908                 let mut secret = [0; 32];
1909                 secret[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1910                 monitor.provide_secret(281474976710655, secret.clone(), None).unwrap();
1911                 assert_eq!(monitor.payment_preimages.len(), 15);
1912                 test_preimages_exist!(&preimages[0..10], monitor);
1913                 test_preimages_exist!(&preimages[15..20], monitor);
1914
1915                 // Now provide a further secret, pruning preimages 15-17
1916                 secret[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1917                 monitor.provide_secret(281474976710654, secret.clone(), None).unwrap();
1918                 assert_eq!(monitor.payment_preimages.len(), 13);
1919                 test_preimages_exist!(&preimages[0..10], monitor);
1920                 test_preimages_exist!(&preimages[17..20], monitor);
1921
1922                 // Now update local commitment tx info, pruning only element 18 as we still care about the
1923                 // previous commitment tx's preimages too
1924                 monitor.provide_latest_local_commitment_tx_info(dummy_tx.clone(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..5]));
1925                 secret[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1926                 monitor.provide_secret(281474976710653, secret.clone(), None).unwrap();
1927                 assert_eq!(monitor.payment_preimages.len(), 12);
1928                 test_preimages_exist!(&preimages[0..10], monitor);
1929                 test_preimages_exist!(&preimages[18..20], monitor);
1930
1931                 // But if we do it again, we'll prune 5-10
1932                 monitor.provide_latest_local_commitment_tx_info(dummy_tx.clone(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..3]));
1933                 secret[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1934                 monitor.provide_secret(281474976710652, secret.clone(), None).unwrap();
1935                 assert_eq!(monitor.payment_preimages.len(), 5);
1936                 test_preimages_exist!(&preimages[0..5], monitor);
1937         }
1938
1939         // Further testing is done in the ChannelManager integration tests.
1940 }