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

   1 //! The logic to monitor for on-chain transactions and create the relevant claim responses lives
   2 //! here.
   3 //!
   4 //! ChannelMonitor objects are generated by ChannelManager in response to relevant
   5 //! messages/actions, and MUST be persisted to disk (and, preferably, remotely) before progress can
   6 //! be made in responding to certain messages, see ManyChannelMonitor for more.
   7 //!
   8 //! Note that ChannelMonitors are an important part of the lightning trust model and a copy of the
   9 //! latest ChannelMonitor must always be actively monitoring for chain updates (and no out-of-date
  10 //! ChannelMonitors should do so). Thus, if you're building rust-lightning into an HSM or other
  11 //! security-domain-separated system design, you should consider having multiple paths for
  12 //! ChannelMonitors to get out of the HSM and onto monitoring devices.
  13
  14 use bitcoin::blockdata::block::BlockHeader;
  15 use bitcoin::blockdata::transaction::{TxIn,TxOut,SigHashType,Transaction};
  16 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
  17 use bitcoin::blockdata::script::{Script, Builder};
  18 use bitcoin::blockdata::opcodes;
  19 use bitcoin::consensus::encode::{self, Decodable, Encodable};
  20 use bitcoin::util::hash::{Hash160, BitcoinHash,Sha256dHash};
  21 use bitcoin::util::bip143;
  22
  23 use crypto::digest::Digest;
  24
  25 use secp256k1::{Secp256k1,Message,Signature};
  26 use secp256k1::key::{SecretKey,PublicKey};
  27 use secp256k1;
  28
  29 use ln::msgs::DecodeError;
  30 use ln::chan_utils;
  31 use ln::chan_utils::HTLCOutputInCommitment;
  32 use chain::chaininterface::{ChainListener, ChainWatchInterface, BroadcasterInterface};
  33 use chain::transaction::OutPoint;
  34 use chain::keysinterface::SpendableOutputDescriptor;
  35 use util::logger::Logger;
  36 use util::ser::{ReadableArgs, Readable, Writer, Writeable, WriterWriteAdaptor, U48};
  37 use util::sha2::Sha256;
  38 use util::{byte_utils, events};
  39
  40 use std::collections::HashMap;
  41 use std::sync::{Arc,Mutex};
  42 use std::{hash,cmp, mem};
  43
  44 /// An error enum representing a failure to persist a channel monitor update.
  45 #[derive(Clone)]
  46 pub enum ChannelMonitorUpdateErr {
  47         /// Used to indicate a temporary failure (eg connection to a watchtower failed, but is expected
  48         /// to succeed at some point in the future).
  49         ///
  50         /// Such a failure will "freeze" a channel, preventing us from revoking old states or
  51         /// submitting new commitment transactions to the remote party.
  52         /// ChannelManager::test_restore_channel_monitor can be used to retry the update(s) and restore
  53         /// the channel to an operational state.
  54         ///
  55         /// Note that continuing to operate when no copy of the updated ChannelMonitor could be
  56         /// persisted is unsafe - if you failed to store the update on your own local disk you should
  57         /// instead return PermanentFailure to force closure of the channel ASAP.
  58         ///
  59         /// Even when a channel has been "frozen" updates to the ChannelMonitor can continue to occur
  60         /// (eg if an inbound HTLC which we forwarded was claimed upstream resulting in us attempting
  61         /// to claim it on this channel) and those updates must be applied wherever they can be. At
  62         /// least one such updated ChannelMonitor must be persisted otherwise PermanentFailure should
  63         /// be returned to get things on-chain ASAP using only the in-memory copy. Obviously updates to
  64         /// the channel which would invalidate previous ChannelMonitors are not made when a channel has
  65         /// been "frozen".
  66         ///
  67         /// Note that even if updates made after TemporaryFailure succeed you must still call
  68         /// test_restore_channel_monitor to ensure you have the latest monitor and re-enable normal
  69         /// channel operation.
  70         TemporaryFailure,
  71         /// Used to indicate no further channel monitor updates will be allowed (eg we've moved on to a
  72         /// different watchtower and cannot update with all watchtowers that were previously informed
  73         /// of this channel). This will force-close the channel in question.
  74         PermanentFailure,
  75 }
  76
  77 /// General Err type for ChannelMonitor actions. Generally, this implies that the data provided is
  78 /// inconsistent with the ChannelMonitor being called. eg for ChannelMonitor::insert_combine this
  79 /// means you tried to merge two monitors for different channels or for a channel which was
  80 /// restored from a backup and then generated new commitment updates.
  81 /// Contains a human-readable error message.
  82 #[derive(Debug)]
  83 pub struct MonitorUpdateError(pub &'static str);
  84
  85 /// Simple trait indicating ability to track a set of ChannelMonitors and multiplex events between
  86 /// them. Generally should be implemented by keeping a local SimpleManyChannelMonitor and passing
  87 /// events to it, while also taking any add_update_monitor events and passing them to some remote
  88 /// server(s).
  89 ///
  90 /// Note that any updates to a channel's monitor *must* be applied to each instance of the
  91 /// channel's monitor everywhere (including remote watchtowers) *before* this function returns. If
  92 /// an update occurs and a remote watchtower is left with old state, it may broadcast transactions
  93 /// which we have revoked, allowing our counterparty to claim all funds in the channel!
  94 pub trait ManyChannelMonitor: Send + Sync {
  95         /// Adds or updates a monitor for the given `funding_txo`.
  96         ///
  97         /// Implementor must also ensure that the funding_txo outpoint is registered with any relevant
  98         /// ChainWatchInterfaces such that the provided monitor receives block_connected callbacks with
  99         /// any spends of it.
 100         fn add_update_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor) -> Result<(), ChannelMonitorUpdateErr>;
 101 }
 102
 103 /// A simple implementation of a ManyChannelMonitor and ChainListener. Can be used to create a
 104 /// watchtower or watch our own channels.
 105 ///
 106 /// Note that you must provide your own key by which to refer to channels.
 107 ///
 108 /// If you're accepting remote monitors (ie are implementing a watchtower), you must verify that
 109 /// users cannot overwrite a given channel by providing a duplicate key. ie you should probably
 110 /// index by a PublicKey which is required to sign any updates.
 111 ///
 112 /// If you're using this for local monitoring of your own channels, you probably want to use
 113 /// `OutPoint` as the key, which will give you a ManyChannelMonitor implementation.
 114 pub struct SimpleManyChannelMonitor<Key> {
 115         #[cfg(test)] // Used in ChannelManager tests to manipulate channels directly
 116         pub monitors: Mutex<HashMap<Key, ChannelMonitor>>,
 117         #[cfg(not(test))]
 118         monitors: Mutex<HashMap<Key, ChannelMonitor>>,
 119         chain_monitor: Arc<ChainWatchInterface>,
 120         broadcaster: Arc<BroadcasterInterface>,
 121         pending_events: Mutex<Vec<events::Event>>,
 122         logger: Arc<Logger>,
 123 }
 124
 125 impl<Key : Send + cmp::Eq + hash::Hash> ChainListener for SimpleManyChannelMonitor<Key> {
 126         fn block_connected(&self, header: &BlockHeader, height: u32, txn_matched: &[&Transaction], _indexes_of_txn_matched: &[u32]) {
 127                 let block_hash = header.bitcoin_hash();
 128                 let mut new_events: Vec<events::Event> = Vec::with_capacity(0);
 129                 {
 130                         let mut monitors = self.monitors.lock().unwrap();
 131                         for monitor in monitors.values_mut() {
 132                                 let (txn_outputs, spendable_outputs) = monitor.block_connected(txn_matched, height, &block_hash, &*self.broadcaster);
 133                                 if spendable_outputs.len() > 0 {
 134                                         new_events.push(events::Event::SpendableOutputs {
 135                                                 outputs: spendable_outputs,
 136                                         });
 137                                 }
 138                                 for (ref txid, ref outputs) in txn_outputs {
 139                                         for (idx, output) in outputs.iter().enumerate() {
 140                                                 self.chain_monitor.install_watch_outpoint((txid.clone(), idx as u32), &output.script_pubkey);
 141                                         }
 142                                 }
 143                         }
 144                 }
 145                 let mut pending_events = self.pending_events.lock().unwrap();
 146                 pending_events.append(&mut new_events);
 147         }
 148
 149         fn block_disconnected(&self, _: &BlockHeader) { }
 150 }
 151
 152 impl<Key : Send + cmp::Eq + hash::Hash + 'static> SimpleManyChannelMonitor<Key> {
 153         /// Creates a new object which can be used to monitor several channels given the chain
 154         /// interface with which to register to receive notifications.
 155         pub fn new(chain_monitor: Arc<ChainWatchInterface>, broadcaster: Arc<BroadcasterInterface>, logger: Arc<Logger>) -> Arc<SimpleManyChannelMonitor<Key>> {
 156                 let res = Arc::new(SimpleManyChannelMonitor {
 157                         monitors: Mutex::new(HashMap::new()),
 158                         chain_monitor,
 159                         broadcaster,
 160                         pending_events: Mutex::new(Vec::new()),
 161                         logger,
 162                 });
 163                 let weak_res = Arc::downgrade(&res);
 164                 res.chain_monitor.register_listener(weak_res);
 165                 res
 166         }
 167
 168         /// Adds or udpates the monitor which monitors the channel referred to by the given key.
 169         pub fn add_update_monitor_by_key(&self, key: Key, monitor: ChannelMonitor) -> Result<(), MonitorUpdateError> {
 170                 let mut monitors = self.monitors.lock().unwrap();
 171                 match monitors.get_mut(&key) {
 172                         Some(orig_monitor) => {
 173                                 log_trace!(self, "Updating Channel Monitor for channel {}", log_funding_info!(monitor.key_storage));
 174                                 return orig_monitor.insert_combine(monitor);
 175                         },
 176                         None => {}
 177                 };
 178                 match monitor.key_storage {
 179                         Storage::Local { ref funding_info, .. } => {
 180                                 match funding_info {
 181                                         &None => {
 182                                                 return Err(MonitorUpdateError("Try to update a useless monitor without funding_txo !"));
 183                                         },
 184                                         &Some((ref outpoint, ref script)) => {
 185                                                 log_trace!(self, "Got new Channel Monitor for channel {}", log_bytes!(outpoint.to_channel_id()[..]));
 186                                                 self.chain_monitor.install_watch_tx(&outpoint.txid, script);
 187                                                 self.chain_monitor.install_watch_outpoint((outpoint.txid, outpoint.index as u32), script);
 188                                         },
 189                                 }
 190                         },
 191                         Storage::Watchtower { .. } => {
 192                                 self.chain_monitor.watch_all_txn();
 193                         }
 194                 }
 195                 monitors.insert(key, monitor);
 196                 Ok(())
 197         }
 198 }
 199
 200 impl ManyChannelMonitor for SimpleManyChannelMonitor<OutPoint> {
 201         fn add_update_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor) -> Result<(), ChannelMonitorUpdateErr> {
 202                 match self.add_update_monitor_by_key(funding_txo, monitor) {
 203                         Ok(_) => Ok(()),
 204                         Err(_) => Err(ChannelMonitorUpdateErr::PermanentFailure),
 205                 }
 206         }
 207 }
 208
 209 impl<Key : Send + cmp::Eq + hash::Hash> events::EventsProvider for SimpleManyChannelMonitor<Key> {
 210         fn get_and_clear_pending_events(&self) -> Vec<events::Event> {
 211                 let mut pending_events = self.pending_events.lock().unwrap();
 212                 let mut ret = Vec::new();
 213                 mem::swap(&mut ret, &mut *pending_events);
 214                 ret
 215         }
 216 }
 217
 218 /// If an HTLC expires within this many blocks, don't try to claim it in a shared transaction,
 219 /// instead claiming it in its own individual transaction.
 220 const CLTV_SHARED_CLAIM_BUFFER: u32 = 12;
 221 /// If an HTLC expires within this many blocks, force-close the channel to broadcast the
 222 /// HTLC-Success transaction.
 223 /// In other words, this is an upper bound on how many blocks we think it can take us to get a
 224 /// transaction confirmed (and we use it in a few more, equivalent, places).
 225 pub(crate) const CLTV_CLAIM_BUFFER: u32 = 6;
 226 /// Number of blocks by which point we expect our counterparty to have seen new blocks on the
 227 /// network and done a full update_fail_htlc/commitment_signed dance (+ we've updated all our
 228 /// copies of ChannelMonitors, including watchtowers).
 229 pub(crate) const HTLC_FAIL_TIMEOUT_BLOCKS: u32 = 3;
 230
 231 #[derive(Clone, PartialEq)]
 232 enum Storage {
 233         Local {
 234                 revocation_base_key: SecretKey,
 235                 htlc_base_key: SecretKey,
 236                 delayed_payment_base_key: SecretKey,
 237                 payment_base_key: SecretKey,
 238                 shutdown_pubkey: PublicKey,
 239                 prev_latest_per_commitment_point: Option<PublicKey>,
 240                 latest_per_commitment_point: Option<PublicKey>,
 241                 funding_info: Option<(OutPoint, Script)>,
 242         },
 243         Watchtower {
 244                 revocation_base_key: PublicKey,
 245                 htlc_base_key: PublicKey,
 246         }
 247 }
 248
 249 #[derive(Clone, PartialEq)]
 250 struct LocalSignedTx {
 251         /// txid of the transaction in tx, just used to make comparison faster
 252         txid: Sha256dHash,
 253         tx: Transaction,
 254         revocation_key: PublicKey,
 255         a_htlc_key: PublicKey,
 256         b_htlc_key: PublicKey,
 257         delayed_payment_key: PublicKey,
 258         feerate_per_kw: u64,
 259         htlc_outputs: Vec<(HTLCOutputInCommitment, Signature, Signature)>,
 260 }
 261
 262 const SERIALIZATION_VERSION: u8 = 1;
 263 const MIN_SERIALIZATION_VERSION: u8 = 1;
 264
 265 /// A ChannelMonitor handles chain events (blocks connected and disconnected) and generates
 266 /// on-chain transactions to ensure no loss of funds occurs.
 267 ///
 268 /// You MUST ensure that no ChannelMonitors for a given channel anywhere contain out-of-date
 269 /// information and are actively monitoring the chain.
 270 #[derive(Clone)]
 271 pub struct ChannelMonitor {
 272         commitment_transaction_number_obscure_factor: u64,
 273
 274         key_storage: Storage,
 275         their_htlc_base_key: Option<PublicKey>,
 276         their_delayed_payment_base_key: Option<PublicKey>,
 277         // first is the idx of the first of the two revocation points
 278         their_cur_revocation_points: Option<(u64, PublicKey, Option<PublicKey>)>,
 279
 280         our_to_self_delay: u16,
 281         their_to_self_delay: Option<u16>,
 282
 283         old_secrets: [([u8; 32], u64); 49],
 284         remote_claimable_outpoints: HashMap<Sha256dHash, Vec<HTLCOutputInCommitment>>,
 285         /// We cannot identify HTLC-Success or HTLC-Timeout transactions by themselves on the chain.
 286         /// Nor can we figure out their commitment numbers without the commitment transaction they are
 287         /// spending. Thus, in order to claim them via revocation key, we track all the remote
 288         /// commitment transactions which we find on-chain, mapping them to the commitment number which
 289         /// can be used to derive the revocation key and claim the transactions.
 290         remote_commitment_txn_on_chain: HashMap<Sha256dHash, (u64, Vec<Script>)>,
 291         /// Cache used to make pruning of payment_preimages faster.
 292         /// Maps payment_hash values to commitment numbers for remote transactions for non-revoked
 293         /// remote transactions (ie should remain pretty small).
 294         /// Serialized to disk but should generally not be sent to Watchtowers.
 295         remote_hash_commitment_number: HashMap<[u8; 32], u64>,
 296
 297         // We store two local commitment transactions to avoid any race conditions where we may update
 298         // some monitors (potentially on watchtowers) but then fail to update others, resulting in the
 299         // various monitors for one channel being out of sync, and us broadcasting a local
 300         // transaction for which we have deleted claim information on some watchtowers.
 301         prev_local_signed_commitment_tx: Option<LocalSignedTx>,
 302         current_local_signed_commitment_tx: Option<LocalSignedTx>,
 303
 304         // Used just for ChannelManager to make sure it has the latest channel data during
 305         // deserialization
 306         current_remote_commitment_number: u64,
 307
 308         payment_preimages: HashMap<[u8; 32], [u8; 32]>,
 309
 310         destination_script: Script,
 311
 312         // We simply modify last_block_hash in Channel's block_connected so that serialization is
 313         // consistent but hopefully the users' copy handles block_connected in a consistent way.
 314         // (we do *not*, however, update them in insert_combine to ensure any local user copies keep
 315         // their last_block_hash from its state and not based on updated copies that didn't run through
 316         // the full block_connected).
 317         pub(crate) last_block_hash: Sha256dHash,
 318         secp_ctx: Secp256k1<secp256k1::All>, //TODO: dedup this a bit...
 319         logger: Arc<Logger>,
 320 }
 321
 322 #[cfg(any(test, feature = "fuzztarget"))]
 323 /// Used only in testing and fuzztarget to check serialization roundtrips don't change the
 324 /// underlying object
 325 impl PartialEq for ChannelMonitor {
 326         fn eq(&self, other: &Self) -> bool {
 327                 if self.commitment_transaction_number_obscure_factor != other.commitment_transaction_number_obscure_factor ||
 328                         self.key_storage != other.key_storage ||
 329                         self.their_htlc_base_key != other.their_htlc_base_key ||
 330                         self.their_delayed_payment_base_key != other.their_delayed_payment_base_key ||
 331                         self.their_cur_revocation_points != other.their_cur_revocation_points ||
 332                         self.our_to_self_delay != other.our_to_self_delay ||
 333                         self.their_to_self_delay != other.their_to_self_delay ||
 334                         self.remote_claimable_outpoints != other.remote_claimable_outpoints ||
 335                         self.remote_commitment_txn_on_chain != other.remote_commitment_txn_on_chain ||
 336                         self.remote_hash_commitment_number != other.remote_hash_commitment_number ||
 337                         self.prev_local_signed_commitment_tx != other.prev_local_signed_commitment_tx ||
 338                         self.current_remote_commitment_number != other.current_remote_commitment_number ||
 339                         self.current_local_signed_commitment_tx != other.current_local_signed_commitment_tx ||
 340                         self.payment_preimages != other.payment_preimages ||
 341                         self.destination_script != other.destination_script
 342                 {
 343                         false
 344                 } else {
 345                         for (&(ref secret, ref idx), &(ref o_secret, ref o_idx)) in self.old_secrets.iter().zip(other.old_secrets.iter()) {
 346                                 if secret != o_secret || idx != o_idx {
 347                                         return false
 348                                 }
 349                         }
 350                         true
 351                 }
 352         }
 353 }
 354
 355 impl ChannelMonitor {
 356         pub(super) fn new(revocation_base_key: &SecretKey, delayed_payment_base_key: &SecretKey, htlc_base_key: &SecretKey, payment_base_key: &SecretKey, shutdown_pubkey: &PublicKey, our_to_self_delay: u16, destination_script: Script, logger: Arc<Logger>) -> ChannelMonitor {
 357                 ChannelMonitor {
 358                         commitment_transaction_number_obscure_factor: 0,
 359
 360                         key_storage: Storage::Local {
 361                                 revocation_base_key: revocation_base_key.clone(),
 362                                 htlc_base_key: htlc_base_key.clone(),
 363                                 delayed_payment_base_key: delayed_payment_base_key.clone(),
 364                                 payment_base_key: payment_base_key.clone(),
 365                                 shutdown_pubkey: shutdown_pubkey.clone(),
 366                                 prev_latest_per_commitment_point: None,
 367                                 latest_per_commitment_point: None,
 368                                 funding_info: None,
 369                         },
 370                         their_htlc_base_key: None,
 371                         their_delayed_payment_base_key: None,
 372                         their_cur_revocation_points: None,
 373
 374                         our_to_self_delay: our_to_self_delay,
 375                         their_to_self_delay: None,
 376
 377                         old_secrets: [([0; 32], 1 << 48); 49],
 378                         remote_claimable_outpoints: HashMap::new(),
 379                         remote_commitment_txn_on_chain: HashMap::new(),
 380                         remote_hash_commitment_number: HashMap::new(),
 381
 382                         prev_local_signed_commitment_tx: None,
 383                         current_local_signed_commitment_tx: None,
 384                         current_remote_commitment_number: 1 << 48,
 385
 386                         payment_preimages: HashMap::new(),
 387                         destination_script: destination_script,
 388
 389                         last_block_hash: Default::default(),
 390                         secp_ctx: Secp256k1::new(),
 391                         logger,
 392                 }
 393         }
 394
 395         #[inline]
 396         fn place_secret(idx: u64) -> u8 {
 397                 for i in 0..48 {
 398                         if idx & (1 << i) == (1 << i) {
 399                                 return i
 400                         }
 401                 }
 402                 48
 403         }
 404
 405         #[inline]
 406         fn derive_secret(secret: [u8; 32], bits: u8, idx: u64) -> [u8; 32] {
 407                 let mut res: [u8; 32] = secret;
 408                 for i in 0..bits {
 409                         let bitpos = bits - 1 - i;
 410                         if idx & (1 << bitpos) == (1 << bitpos) {
 411                                 res[(bitpos / 8) as usize] ^= 1 << (bitpos & 7);
 412                                 let mut sha = Sha256::new();
 413                                 sha.input(&res);
 414                                 sha.result(&mut res);
 415                         }
 416                 }
 417                 res
 418         }
 419
 420         /// Inserts a revocation secret into this channel monitor. Prunes old preimages if neither
 421         /// needed by local commitment transactions HTCLs nor by remote ones. Unless we haven't already seen remote
 422         /// commitment transaction's secret, they are de facto pruned (we can use revocation key).
 423         pub(super) fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), MonitorUpdateError> {
 424                 let pos = ChannelMonitor::place_secret(idx);
 425                 for i in 0..pos {
 426                         let (old_secret, old_idx) = self.old_secrets[i as usize];
 427                         if ChannelMonitor::derive_secret(secret, pos, old_idx) != old_secret {
 428                                 return Err(MonitorUpdateError("Previous secret did not match new one"));
 429                         }
 430                 }
 431                 self.old_secrets[pos as usize] = (secret, idx);
 432
 433                 if !self.payment_preimages.is_empty() {
 434                         let local_signed_commitment_tx = self.current_local_signed_commitment_tx.as_ref().expect("Channel needs at least an initial commitment tx !");
 435                         let prev_local_signed_commitment_tx = self.prev_local_signed_commitment_tx.as_ref();
 436                         let min_idx = self.get_min_seen_secret();
 437                         let remote_hash_commitment_number = &mut self.remote_hash_commitment_number;
 438
 439                         self.payment_preimages.retain(|&k, _| {
 440                                 for &(ref htlc, _, _) in &local_signed_commitment_tx.htlc_outputs {
 441                                         if k == htlc.payment_hash {
 442                                                 return true
 443                                         }
 444                                 }
 445                                 if let Some(prev_local_commitment_tx) = prev_local_signed_commitment_tx {
 446                                         for &(ref htlc, _, _) in prev_local_commitment_tx.htlc_outputs.iter() {
 447                                                 if k == htlc.payment_hash {
 448                                                         return true
 449                                                 }
 450                                         }
 451                                 }
 452                                 let contains = if let Some(cn) = remote_hash_commitment_number.get(&k) {
 453                                         if *cn < min_idx {
 454                                                 return true
 455                                         }
 456                                         true
 457                                 } else { false };
 458                                 if contains {
 459                                         remote_hash_commitment_number.remove(&k);
 460                                 }
 461                                 false
 462                         });
 463                 }
 464
 465                 Ok(())
 466         }
 467
 468         /// Informs this monitor of the latest remote (ie non-broadcastable) commitment transaction.
 469         /// The monitor watches for it to be broadcasted and then uses the HTLC information (and
 470         /// possibly future revocation/preimage information) to claim outputs where possible.
 471         /// We cache also the mapping hash:commitment number to lighten pruning of old preimages by watchtowers.
 472         pub(super) fn provide_latest_remote_commitment_tx_info(&mut self, unsigned_commitment_tx: &Transaction, htlc_outputs: Vec<HTLCOutputInCommitment>, commitment_number: u64, their_revocation_point: PublicKey) {
 473                 // TODO: Encrypt the htlc_outputs data with the single-hash of the commitment transaction
 474                 // so that a remote monitor doesn't learn anything unless there is a malicious close.
 475                 // (only maybe, sadly we cant do the same for local info, as we need to be aware of
 476                 // timeouts)
 477                 for htlc in &htlc_outputs {
 478                         self.remote_hash_commitment_number.insert(htlc.payment_hash, commitment_number);
 479                 }
 480                 self.remote_claimable_outpoints.insert(unsigned_commitment_tx.txid(), htlc_outputs);
 481                 self.current_remote_commitment_number = commitment_number;
 482                 //TODO: Merge this into the other per-remote-transaction output storage stuff
 483                 match self.their_cur_revocation_points {
 484                         Some(old_points) => {
 485                                 if old_points.0 == commitment_number + 1 {
 486                                         self.their_cur_revocation_points = Some((old_points.0, old_points.1, Some(their_revocation_point)));
 487                                 } else if old_points.0 == commitment_number + 2 {
 488                                         if let Some(old_second_point) = old_points.2 {
 489                                                 self.their_cur_revocation_points = Some((old_points.0 - 1, old_second_point, Some(their_revocation_point)));
 490                                         } else {
 491                                                 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
 492                                         }
 493                                 } else {
 494                                         self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
 495                                 }
 496                         },
 497                         None => {
 498                                 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
 499                         }
 500                 }
 501         }
 502
 503         /// Informs this monitor of the latest local (ie broadcastable) commitment transaction. The
 504         /// monitor watches for timeouts and may broadcast it if we approach such a timeout. Thus, it
 505         /// is important that any clones of this channel monitor (including remote clones) by kept
 506         /// up-to-date as our local commitment transaction is updated.
 507         /// Panics if set_their_to_self_delay has never been called.
 508         /// Also update Storage with latest local per_commitment_point to derive local_delayedkey in
 509         /// case of onchain HTLC tx
 510         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)>) {
 511                 assert!(self.their_to_self_delay.is_some());
 512                 self.prev_local_signed_commitment_tx = self.current_local_signed_commitment_tx.take();
 513                 self.current_local_signed_commitment_tx = Some(LocalSignedTx {
 514                         txid: signed_commitment_tx.txid(),
 515                         tx: signed_commitment_tx,
 516                         revocation_key: local_keys.revocation_key,
 517                         a_htlc_key: local_keys.a_htlc_key,
 518                         b_htlc_key: local_keys.b_htlc_key,
 519                         delayed_payment_key: local_keys.a_delayed_payment_key,
 520                         feerate_per_kw,
 521                         htlc_outputs,
 522                 });
 523
 524                 if let Storage::Local { ref mut latest_per_commitment_point, .. } = self.key_storage {
 525                         *latest_per_commitment_point = Some(local_keys.per_commitment_point);
 526                 } else {
 527                         panic!("Channel somehow ended up with its internal ChannelMonitor being in Watchtower mode?");
 528                 }
 529         }
 530
 531         /// Provides a payment_hash->payment_preimage mapping. Will be automatically pruned when all
 532         /// commitment_tx_infos which contain the payment hash have been revoked.
 533         pub(super) fn provide_payment_preimage(&mut self, payment_hash: &[u8; 32], payment_preimage: &[u8; 32]) {
 534                 self.payment_preimages.insert(payment_hash.clone(), payment_preimage.clone());
 535         }
 536
 537         /// Combines this ChannelMonitor with the information contained in the other ChannelMonitor.
 538         /// After a successful call this ChannelMonitor is up-to-date and is safe to use to monitor the
 539         /// chain for new blocks/transactions.
 540         pub fn insert_combine(&mut self, mut other: ChannelMonitor) -> Result<(), MonitorUpdateError> {
 541                 match self.key_storage {
 542                         Storage::Local { ref funding_info, .. } => {
 543                                 if funding_info.is_none() { return Err(MonitorUpdateError("Try to combine a Local monitor without funding_info")); }
 544                                 let our_funding_info = funding_info;
 545                                 if let Storage::Local { ref funding_info, .. } = other.key_storage {
 546                                         if funding_info.is_none() { return Err(MonitorUpdateError("Try to combine a Local monitor without funding_info")); }
 547                                         // We should be able to compare the entire funding_txo, but in fuzztarget its trivially
 548                                         // easy to collide the funding_txo hash and have a different scriptPubKey.
 549                                         if funding_info.as_ref().unwrap().0 != our_funding_info.as_ref().unwrap().0 {
 550                                                 return Err(MonitorUpdateError("Funding transaction outputs are not identical!"));
 551                                         }
 552                                 } else {
 553                                         return Err(MonitorUpdateError("Try to combine a Local monitor with a Watchtower one !"));
 554                                 }
 555                         },
 556                         Storage::Watchtower { .. } => {
 557                                 if let Storage::Watchtower { .. } = other.key_storage {
 558                                         unimplemented!();
 559                                 } else {
 560                                         return Err(MonitorUpdateError("Try to combine a Watchtower monitor with a Local one !"));
 561                                 }
 562                         },
 563                 }
 564                 let other_min_secret = other.get_min_seen_secret();
 565                 let our_min_secret = self.get_min_seen_secret();
 566                 if our_min_secret > other_min_secret {
 567                         self.provide_secret(other_min_secret, other.get_secret(other_min_secret).unwrap())?;
 568                 }
 569                 if let Some(ref local_tx) = self.current_local_signed_commitment_tx {
 570                         if let Some(ref other_local_tx) = other.current_local_signed_commitment_tx {
 571                                 let our_commitment_number = 0xffffffffffff - ((((local_tx.tx.input[0].sequence as u64 & 0xffffff) << 3*8) | (local_tx.tx.lock_time as u64 & 0xffffff)) ^ self.commitment_transaction_number_obscure_factor);
 572                                 let other_commitment_number = 0xffffffffffff - ((((other_local_tx.tx.input[0].sequence as u64 & 0xffffff) << 3*8) | (other_local_tx.tx.lock_time as u64 & 0xffffff)) ^ other.commitment_transaction_number_obscure_factor);
 573                                 if our_commitment_number >= other_commitment_number {
 574                                         self.key_storage = other.key_storage;
 575                                 }
 576                         }
 577                 }
 578                 // TODO: We should use current_remote_commitment_number and the commitment number out of
 579                 // local transactions to decide how to merge
 580                 if our_min_secret >= other_min_secret {
 581                         self.their_cur_revocation_points = other.their_cur_revocation_points;
 582                         for (txid, htlcs) in other.remote_claimable_outpoints.drain() {
 583                                 self.remote_claimable_outpoints.insert(txid, htlcs);
 584                         }
 585                         if let Some(local_tx) = other.prev_local_signed_commitment_tx {
 586                                 self.prev_local_signed_commitment_tx = Some(local_tx);
 587                         }
 588                         if let Some(local_tx) = other.current_local_signed_commitment_tx {
 589                                 self.current_local_signed_commitment_tx = Some(local_tx);
 590                         }
 591                         self.payment_preimages = other.payment_preimages;
 592                 }
 593
 594                 self.current_remote_commitment_number = cmp::min(self.current_remote_commitment_number, other.current_remote_commitment_number);
 595                 Ok(())
 596         }
 597
 598         /// Panics if commitment_transaction_number_obscure_factor doesn't fit in 48 bits
 599         pub(super) fn set_commitment_obscure_factor(&mut self, commitment_transaction_number_obscure_factor: u64) {
 600                 assert!(commitment_transaction_number_obscure_factor < (1 << 48));
 601                 self.commitment_transaction_number_obscure_factor = commitment_transaction_number_obscure_factor;
 602         }
 603
 604         /// Allows this monitor to scan only for transactions which are applicable. Note that this is
 605         /// optional, without it this monitor cannot be used in an SPV client, but you may wish to
 606         /// avoid this (or call unset_funding_info) on a monitor you wish to send to a watchtower as it
 607         /// provides slightly better privacy.
 608         /// It's the responsibility of the caller to register outpoint and script with passing the former
 609         /// value as key to add_update_monitor.
 610         pub(super) fn set_funding_info(&mut self, new_funding_info: (OutPoint, Script)) {
 611                 match self.key_storage {
 612                         Storage::Local { ref mut funding_info, .. } => {
 613                                 *funding_info = Some(new_funding_info);
 614                         },
 615                         Storage::Watchtower { .. } => {
 616                                 panic!("Channel somehow ended up with its internal ChannelMonitor being in Watchtower mode?");
 617                         }
 618                 }
 619         }
 620
 621         /// We log these base keys at channel opening to being able to rebuild redeemscript in case of leaked revoked commit tx
 622         pub(super) fn set_their_base_keys(&mut self, their_htlc_base_key: &PublicKey, their_delayed_payment_base_key: &PublicKey) {
 623                 self.their_htlc_base_key = Some(their_htlc_base_key.clone());
 624                 self.their_delayed_payment_base_key = Some(their_delayed_payment_base_key.clone());
 625         }
 626
 627         pub(super) fn set_their_to_self_delay(&mut self, their_to_self_delay: u16) {
 628                 self.their_to_self_delay = Some(their_to_self_delay);
 629         }
 630
 631         pub(super) fn unset_funding_info(&mut self) {
 632                 match self.key_storage {
 633                         Storage::Local { ref mut funding_info, .. } => {
 634                                 *funding_info = None;
 635                         },
 636                         Storage::Watchtower { .. } => {
 637                                 panic!("Channel somehow ended up with its internal ChannelMonitor being in Watchtower mode?");
 638                         },
 639                 }
 640         }
 641
 642         /// Gets the funding transaction outpoint of the channel this ChannelMonitor is monitoring for.
 643         pub fn get_funding_txo(&self) -> Option<OutPoint> {
 644                 match self.key_storage {
 645                         Storage::Local { ref funding_info, .. } => {
 646                                 match funding_info {
 647                                         &Some((outpoint, _)) => Some(outpoint),
 648                                         &None => None
 649                                 }
 650                         },
 651                         Storage::Watchtower { .. } => {
 652                                 return None;
 653                         }
 654                 }
 655         }
 656
 657         /// Gets the sets of all outpoints which this ChannelMonitor expects to hear about spends of.
 658         /// Generally useful when deserializing as during normal operation the return values of
 659         /// block_connected are sufficient to ensure all relevant outpoints are being monitored (note
 660         /// that the get_funding_txo outpoint and transaction must also be monitored for!).
 661         pub fn get_monitored_outpoints(&self) -> Vec<(Sha256dHash, u32, &Script)> {
 662                 let mut res = Vec::with_capacity(self.remote_commitment_txn_on_chain.len() * 2);
 663                 for (ref txid, &(_, ref outputs)) in self.remote_commitment_txn_on_chain.iter() {
 664                         for (idx, output) in outputs.iter().enumerate() {
 665                                 res.push(((*txid).clone(), idx as u32, output));
 666                         }
 667                 }
 668                 res
 669         }
 670
 671         /// Serializes into a vec, with various modes for the exposed pub fns
 672         fn write<W: Writer>(&self, writer: &mut W, for_local_storage: bool) -> Result<(), ::std::io::Error> {
 673                 //TODO: We still write out all the serialization here manually instead of using the fancy
 674                 //serialization framework we have, we should migrate things over to it.
 675                 writer.write_all(&[SERIALIZATION_VERSION; 1])?;
 676                 writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
 677
 678                 // Set in initial Channel-object creation, so should always be set by now:
 679                 U48(self.commitment_transaction_number_obscure_factor).write(writer)?;
 680
 681                 match self.key_storage {
 682                         Storage::Local { ref revocation_base_key, ref htlc_base_key, ref delayed_payment_base_key, ref payment_base_key, ref shutdown_pubkey, ref prev_latest_per_commitment_point, ref latest_per_commitment_point, ref funding_info } => {
 683                                 writer.write_all(&[0; 1])?;
 684                                 writer.write_all(&revocation_base_key[..])?;
 685                                 writer.write_all(&htlc_base_key[..])?;
 686                                 writer.write_all(&delayed_payment_base_key[..])?;
 687                                 writer.write_all(&payment_base_key[..])?;
 688                                 writer.write_all(&shutdown_pubkey.serialize())?;
 689                                 if let Some(ref prev_latest_per_commitment_point) = *prev_latest_per_commitment_point {
 690                                         writer.write_all(&[1; 1])?;
 691                                         writer.write_all(&prev_latest_per_commitment_point.serialize())?;
 692                                 } else {
 693                                         writer.write_all(&[0; 1])?;
 694                                 }
 695                                 if let Some(ref latest_per_commitment_point) = *latest_per_commitment_point {
 696                                         writer.write_all(&[1; 1])?;
 697                                         writer.write_all(&latest_per_commitment_point.serialize())?;
 698                                 } else {
 699                                         writer.write_all(&[0; 1])?;
 700                                 }
 701                                 match funding_info  {
 702                                         &Some((ref outpoint, ref script)) => {
 703                                                 writer.write_all(&outpoint.txid[..])?;
 704                                                 writer.write_all(&byte_utils::be16_to_array(outpoint.index))?;
 705                                                 script.write(writer)?;
 706                                         },
 707                                         &None => {
 708                                                 debug_assert!(false, "Try to serialize a useless Local monitor !");
 709                                         },
 710                                 }
 711                         },
 712                         Storage::Watchtower { .. } => unimplemented!(),
 713                 }
 714
 715                 writer.write_all(&self.their_htlc_base_key.as_ref().unwrap().serialize())?;
 716                 writer.write_all(&self.their_delayed_payment_base_key.as_ref().unwrap().serialize())?;
 717
 718                 match self.their_cur_revocation_points {
 719                         Some((idx, pubkey, second_option)) => {
 720                                 writer.write_all(&byte_utils::be48_to_array(idx))?;
 721                                 writer.write_all(&pubkey.serialize())?;
 722                                 match second_option {
 723                                         Some(second_pubkey) => {
 724                                                 writer.write_all(&second_pubkey.serialize())?;
 725                                         },
 726                                         None => {
 727                                                 writer.write_all(&[0; 33])?;
 728                                         },
 729                                 }
 730                         },
 731                         None => {
 732                                 writer.write_all(&byte_utils::be48_to_array(0))?;
 733                         },
 734                 }
 735
 736                 writer.write_all(&byte_utils::be16_to_array(self.our_to_self_delay))?;
 737                 writer.write_all(&byte_utils::be16_to_array(self.their_to_self_delay.unwrap()))?;
 738
 739                 for &(ref secret, ref idx) in self.old_secrets.iter() {
 740                         writer.write_all(secret)?;
 741                         writer.write_all(&byte_utils::be64_to_array(*idx))?;
 742                 }
 743
 744                 macro_rules! serialize_htlc_in_commitment {
 745                         ($htlc_output: expr) => {
 746                                 writer.write_all(&[$htlc_output.offered as u8; 1])?;
 747                                 writer.write_all(&byte_utils::be64_to_array($htlc_output.amount_msat))?;
 748                                 writer.write_all(&byte_utils::be32_to_array($htlc_output.cltv_expiry))?;
 749                                 writer.write_all(&$htlc_output.payment_hash)?;
 750                                 writer.write_all(&byte_utils::be32_to_array($htlc_output.transaction_output_index))?;
 751                         }
 752                 }
 753
 754                 writer.write_all(&byte_utils::be64_to_array(self.remote_claimable_outpoints.len() as u64))?;
 755                 for (ref txid, ref htlc_outputs) in self.remote_claimable_outpoints.iter() {
 756                         writer.write_all(&txid[..])?;
 757                         writer.write_all(&byte_utils::be64_to_array(htlc_outputs.len() as u64))?;
 758                         for htlc_output in htlc_outputs.iter() {
 759                                 serialize_htlc_in_commitment!(htlc_output);
 760                         }
 761                 }
 762
 763                 writer.write_all(&byte_utils::be64_to_array(self.remote_commitment_txn_on_chain.len() as u64))?;
 764                 for (ref txid, &(commitment_number, ref txouts)) in self.remote_commitment_txn_on_chain.iter() {
 765                         writer.write_all(&txid[..])?;
 766                         writer.write_all(&byte_utils::be48_to_array(commitment_number))?;
 767                         (txouts.len() as u64).write(writer)?;
 768                         for script in txouts.iter() {
 769                                 script.write(writer)?;
 770                         }
 771                 }
 772
 773                 if for_local_storage {
 774                         writer.write_all(&byte_utils::be64_to_array(self.remote_hash_commitment_number.len() as u64))?;
 775                         for (ref payment_hash, commitment_number) in self.remote_hash_commitment_number.iter() {
 776                                 writer.write_all(*payment_hash)?;
 777                                 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
 778                         }
 779                 } else {
 780                         writer.write_all(&byte_utils::be64_to_array(0))?;
 781                 }
 782
 783                 macro_rules! serialize_local_tx {
 784                         ($local_tx: expr) => {
 785                                 if let Err(e) = $local_tx.tx.consensus_encode(&mut WriterWriteAdaptor(writer)) {
 786                                         match e {
 787                                                 encode::Error::Io(e) => return Err(e),
 788                                                 _ => panic!("local tx must have been well-formed!"),
 789                                         }
 790                                 }
 791
 792                                 writer.write_all(&$local_tx.revocation_key.serialize())?;
 793                                 writer.write_all(&$local_tx.a_htlc_key.serialize())?;
 794                                 writer.write_all(&$local_tx.b_htlc_key.serialize())?;
 795                                 writer.write_all(&$local_tx.delayed_payment_key.serialize())?;
 796
 797                                 writer.write_all(&byte_utils::be64_to_array($local_tx.feerate_per_kw))?;
 798                                 writer.write_all(&byte_utils::be64_to_array($local_tx.htlc_outputs.len() as u64))?;
 799                                 for &(ref htlc_output, ref their_sig, ref our_sig) in $local_tx.htlc_outputs.iter() {
 800                                         serialize_htlc_in_commitment!(htlc_output);
 801                                         writer.write_all(&their_sig.serialize_compact(&self.secp_ctx))?;
 802                                         writer.write_all(&our_sig.serialize_compact(&self.secp_ctx))?;
 803                                 }
 804                         }
 805                 }
 806
 807                 if let Some(ref prev_local_tx) = self.prev_local_signed_commitment_tx {
 808                         writer.write_all(&[1; 1])?;
 809                         serialize_local_tx!(prev_local_tx);
 810                 } else {
 811                         writer.write_all(&[0; 1])?;
 812                 }
 813
 814                 if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
 815                         writer.write_all(&[1; 1])?;
 816                         serialize_local_tx!(cur_local_tx);
 817                 } else {
 818                         writer.write_all(&[0; 1])?;
 819                 }
 820
 821                 if for_local_storage {
 822                         writer.write_all(&byte_utils::be48_to_array(self.current_remote_commitment_number))?;
 823                 } else {
 824                         writer.write_all(&byte_utils::be48_to_array(0))?;
 825                 }
 826
 827                 writer.write_all(&byte_utils::be64_to_array(self.payment_preimages.len() as u64))?;
 828                 for payment_preimage in self.payment_preimages.values() {
 829                         writer.write_all(payment_preimage)?;
 830                 }
 831
 832                 self.last_block_hash.write(writer)?;
 833                 self.destination_script.write(writer)?;
 834
 835                 Ok(())
 836         }
 837
 838         /// Writes this monitor into the given writer, suitable for writing to disk.
 839         ///
 840         /// Note that the deserializer is only implemented for (Sha256dHash, ChannelMonitor), which
 841         /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
 842         /// the "reorg path" (ie not just starting at the same height but starting at the highest
 843         /// common block that appears on your best chain as well as on the chain which contains the
 844         /// last block hash returned) upon deserializing the object!
 845         pub fn write_for_disk<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
 846                 self.write(writer, true)
 847         }
 848
 849         /// Encodes this monitor into the given writer, suitable for sending to a remote watchtower
 850         ///
 851         /// Note that the deserializer is only implemented for (Sha256dHash, ChannelMonitor), which
 852         /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
 853         /// the "reorg path" (ie not just starting at the same height but starting at the highest
 854         /// common block that appears on your best chain as well as on the chain which contains the
 855         /// last block hash returned) upon deserializing the object!
 856         pub fn write_for_watchtower<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
 857                 self.write(writer, false)
 858         }
 859
 860         //TODO: Functions to serialize/deserialize (with different forms depending on which information
 861         //we want to leave out (eg funding_txo, etc).
 862
 863         /// Can only fail if idx is < get_min_seen_secret
 864         pub(super) fn get_secret(&self, idx: u64) -> Option<[u8; 32]> {
 865                 for i in 0..self.old_secrets.len() {
 866                         if (idx & (!((1 << i) - 1))) == self.old_secrets[i].1 {
 867                                 return Some(ChannelMonitor::derive_secret(self.old_secrets[i].0, i as u8, idx))
 868                         }
 869                 }
 870                 assert!(idx < self.get_min_seen_secret());
 871                 None
 872         }
 873
 874         pub(super) fn get_min_seen_secret(&self) -> u64 {
 875                 //TODO This can be optimized?
 876                 let mut min = 1 << 48;
 877                 for &(_, idx) in self.old_secrets.iter() {
 878                         if idx < min {
 879                                 min = idx;
 880                         }
 881                 }
 882                 min
 883         }
 884
 885         pub(super) fn get_cur_remote_commitment_number(&self) -> u64 {
 886                 self.current_remote_commitment_number
 887         }
 888
 889         pub(super) fn get_cur_local_commitment_number(&self) -> u64 {
 890                 if let &Some(ref local_tx) = &self.current_local_signed_commitment_tx {
 891                         0xffff_ffff_ffff - ((((local_tx.tx.input[0].sequence as u64 & 0xffffff) << 3*8) | (local_tx.tx.lock_time as u64 & 0xffffff)) ^ self.commitment_transaction_number_obscure_factor)
 892                 } else { 0xffff_ffff_ffff }
 893         }
 894
 895         /// Attempts to claim a remote commitment transaction's outputs using the revocation key and
 896         /// data in remote_claimable_outpoints. Will directly claim any HTLC outputs which expire at a
 897         /// height > height + CLTV_SHARED_CLAIM_BUFFER. In any case, will install monitoring for
 898         /// HTLC-Success/HTLC-Timeout transactions.
 899         fn check_spend_remote_transaction(&mut self, tx: &Transaction, height: u32) -> (Vec<Transaction>, (Sha256dHash, Vec<TxOut>), Vec<SpendableOutputDescriptor>) {
 900                 // Most secp and related errors trying to create keys means we have no hope of constructing
 901                 // a spend transaction...so we return no transactions to broadcast
 902                 let mut txn_to_broadcast = Vec::new();
 903                 let mut watch_outputs = Vec::new();
 904                 let mut spendable_outputs = Vec::new();
 905
 906                 let commitment_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
 907                 let per_commitment_option = self.remote_claimable_outpoints.get(&commitment_txid);
 908
 909                 macro_rules! ignore_error {
 910                         ( $thing : expr ) => {
 911                                 match $thing {
 912                                         Ok(a) => a,
 913                                         Err(_) => return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs)
 914                                 }
 915                         };
 916                 }
 917
 918                 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);
 919                 if commitment_number >= self.get_min_seen_secret() {
 920                         let secret = self.get_secret(commitment_number).unwrap();
 921                         let per_commitment_key = ignore_error!(SecretKey::from_slice(&self.secp_ctx, &secret));
 922                         let (revocation_pubkey, b_htlc_key, local_payment_key) = match self.key_storage {
 923                                 Storage::Local { ref revocation_base_key, ref htlc_base_key, ref payment_base_key, .. } => {
 924                                         let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
 925                                         (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &PublicKey::from_secret_key(&self.secp_ctx, &revocation_base_key))),
 926                                         ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &PublicKey::from_secret_key(&self.secp_ctx, &htlc_base_key))),
 927                                         Some(ignore_error!(chan_utils::derive_private_key(&self.secp_ctx, &per_commitment_point, &payment_base_key))))
 928                                 },
 929                                 Storage::Watchtower { ref revocation_base_key, ref htlc_base_key, .. } => {
 930                                         let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
 931                                         (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &revocation_base_key)),
 932                                         ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &htlc_base_key)),
 933                                         None)
 934                                 },
 935                         };
 936                         let delayed_key = ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key), &self.their_delayed_payment_base_key.unwrap()));
 937                         let a_htlc_key = match self.their_htlc_base_key {
 938                                 None => return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs),
 939                                 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)),
 940                         };
 941
 942                         let revokeable_redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.our_to_self_delay, &delayed_key);
 943                         let revokeable_p2wsh = revokeable_redeemscript.to_v0_p2wsh();
 944
 945                         let local_payment_p2wpkh = if let Some(payment_key) = local_payment_key {
 946                                 // Note that the Network here is ignored as we immediately drop the address for the
 947                                 // script_pubkey version.
 948                                 let payment_hash160 = Hash160::from_data(&PublicKey::from_secret_key(&self.secp_ctx, &payment_key).serialize());
 949                                 Some(Builder::new().push_opcode(opcodes::All::OP_PUSHBYTES_0).push_slice(&payment_hash160[..]).into_script())
 950                         } else { None };
 951
 952                         let mut total_value = 0;
 953                         let mut values = Vec::new();
 954                         let mut inputs = Vec::new();
 955                         let mut htlc_idxs = Vec::new();
 956
 957                         for (idx, outp) in tx.output.iter().enumerate() {
 958                                 if outp.script_pubkey == revokeable_p2wsh {
 959                                         inputs.push(TxIn {
 960                                                 previous_output: BitcoinOutPoint {
 961                                                         txid: commitment_txid,
 962                                                         vout: idx as u32,
 963                                                 },
 964                                                 script_sig: Script::new(),
 965                                                 sequence: 0xfffffffd,
 966                                                 witness: Vec::new(),
 967                                         });
 968                                         htlc_idxs.push(None);
 969                                         values.push(outp.value);
 970                                         total_value += outp.value;
 971                                 } else if Some(&outp.script_pubkey) == local_payment_p2wpkh.as_ref() {
 972                                         spendable_outputs.push(SpendableOutputDescriptor::DynamicOutputP2WPKH {
 973                                                 outpoint: BitcoinOutPoint { txid: commitment_txid, vout: idx as u32 },
 974                                                 key: local_payment_key.unwrap(),
 975                                                 output: outp.clone(),
 976                                         });
 977                                 }
 978                         }
 979
 980                         macro_rules! sign_input {
 981                                 ($sighash_parts: expr, $input: expr, $htlc_idx: expr, $amount: expr) => {
 982                                         {
 983                                                 let (sig, redeemscript) = match self.key_storage {
 984                                                         Storage::Local { ref revocation_base_key, .. } => {
 985                                                                 let redeemscript = if $htlc_idx.is_none() { revokeable_redeemscript.clone() } else {
 986                                                                         let htlc = &per_commitment_option.unwrap()[$htlc_idx.unwrap()];
 987                                                                         chan_utils::get_htlc_redeemscript_with_explicit_keys(htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey)
 988                                                                 };
 989                                                                 let sighash = ignore_error!(Message::from_slice(&$sighash_parts.sighash_all(&$input, &redeemscript, $amount)[..]));
 990                                                                 let revocation_key = ignore_error!(chan_utils::derive_private_revocation_key(&self.secp_ctx, &per_commitment_key, &revocation_base_key));
 991                                                                 (self.secp_ctx.sign(&sighash, &revocation_key), redeemscript)
 992                                                         },
 993                                                         Storage::Watchtower { .. } => {
 994                                                                 unimplemented!();
 995                                                         }
 996                                                 };
 997                                                 $input.witness.push(sig.serialize_der(&self.secp_ctx).to_vec());
 998                                                 $input.witness[0].push(SigHashType::All as u8);
 999                                                 if $htlc_idx.is_none() {
1000                                                         $input.witness.push(vec!(1));
1001                                                 } else {
1002                                                         $input.witness.push(revocation_pubkey.serialize().to_vec());
1003                                                 }
1004                                                 $input.witness.push(redeemscript.into_bytes());
1005                                         }
1006                                 }
1007                         }
1008
1009                         if let Some(per_commitment_data) = per_commitment_option {
1010                                 inputs.reserve_exact(per_commitment_data.len());
1011
1012                                 for (idx, htlc) in per_commitment_data.iter().enumerate() {
1013                                         let expected_script = chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey);
1014                                         if htlc.transaction_output_index as usize >= tx.output.len() ||
1015                                                         tx.output[htlc.transaction_output_index as usize].value != htlc.amount_msat / 1000 ||
1016                                                         tx.output[htlc.transaction_output_index as usize].script_pubkey != expected_script.to_v0_p2wsh() {
1017                                                 return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs); // Corrupted per_commitment_data, fuck this user
1018                                         }
1019                                         let input = TxIn {
1020                                                 previous_output: BitcoinOutPoint {
1021                                                         txid: commitment_txid,
1022                                                         vout: htlc.transaction_output_index,
1023                                                 },
1024                                                 script_sig: Script::new(),
1025                                                 sequence: 0xfffffffd,
1026                                                 witness: Vec::new(),
1027                                         };
1028                                         if htlc.cltv_expiry > height + CLTV_SHARED_CLAIM_BUFFER {
1029                                                 inputs.push(input);
1030                                                 htlc_idxs.push(Some(idx));
1031                                                 values.push(tx.output[htlc.transaction_output_index as usize].value);
1032                                                 total_value += htlc.amount_msat / 1000;
1033                                         } else {
1034                                                 let mut single_htlc_tx = Transaction {
1035                                                         version: 2,
1036                                                         lock_time: 0,
1037                                                         input: vec![input],
1038                                                         output: vec!(TxOut {
1039                                                                 script_pubkey: self.destination_script.clone(),
1040                                                                 value: htlc.amount_msat / 1000, //TODO: - fee
1041                                                         }),
1042                                                 };
1043                                                 let sighash_parts = bip143::SighashComponents::new(&single_htlc_tx);
1044                                                 sign_input!(sighash_parts, single_htlc_tx.input[0], Some(idx), htlc.amount_msat / 1000);
1045                                                 txn_to_broadcast.push(single_htlc_tx);
1046                                         }
1047                                 }
1048                         }
1049
1050                         if !inputs.is_empty() || !txn_to_broadcast.is_empty() { // ie we're confident this is actually ours
1051                                 // We're definitely a remote commitment transaction!
1052                                 watch_outputs.append(&mut tx.output.clone());
1053                                 self.remote_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
1054                         }
1055                         if inputs.is_empty() { return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs); } // Nothing to be done...probably a false positive/local tx
1056
1057                         let outputs = vec!(TxOut {
1058                                 script_pubkey: self.destination_script.clone(),
1059                                 value: total_value, //TODO: - fee
1060                         });
1061                         let mut spend_tx = Transaction {
1062                                 version: 2,
1063                                 lock_time: 0,
1064                                 input: inputs,
1065                                 output: outputs,
1066                         };
1067
1068                         let mut values_drain = values.drain(..);
1069                         let sighash_parts = bip143::SighashComponents::new(&spend_tx);
1070
1071                         for (input, htlc_idx) in spend_tx.input.iter_mut().zip(htlc_idxs.iter()) {
1072                                 let value = values_drain.next().unwrap();
1073                                 sign_input!(sighash_parts, input, htlc_idx, value);
1074                         }
1075
1076                         spendable_outputs.push(SpendableOutputDescriptor::StaticOutput {
1077                                 outpoint: BitcoinOutPoint { txid: spend_tx.txid(), vout: 0 },
1078                                 output: spend_tx.output[0].clone(),
1079                         });
1080                         txn_to_broadcast.push(spend_tx);
1081                 } else if let Some(per_commitment_data) = per_commitment_option {
1082                         // While this isn't useful yet, there is a potential race where if a counterparty
1083                         // revokes a state at the same time as the commitment transaction for that state is
1084                         // confirmed, and the watchtower receives the block before the user, the user could
1085                         // upload a new ChannelMonitor with the revocation secret but the watchtower has
1086                         // already processed the block, resulting in the remote_commitment_txn_on_chain entry
1087                         // not being generated by the above conditional. Thus, to be safe, we go ahead and
1088                         // insert it here.
1089                         watch_outputs.append(&mut tx.output.clone());
1090                         self.remote_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
1091
1092                         if let Some(revocation_points) = self.their_cur_revocation_points {
1093                                 let revocation_point_option =
1094                                         if revocation_points.0 == commitment_number { Some(&revocation_points.1) }
1095                                         else if let Some(point) = revocation_points.2.as_ref() {
1096                                                 if revocation_points.0 == commitment_number + 1 { Some(point) } else { None }
1097                                         } else { None };
1098                                 if let Some(revocation_point) = revocation_point_option {
1099                                         let (revocation_pubkey, b_htlc_key) = match self.key_storage {
1100                                                 Storage::Local { ref revocation_base_key, ref htlc_base_key, .. } => {
1101                                                         (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, revocation_point, &PublicKey::from_secret_key(&self.secp_ctx, &revocation_base_key))),
1102                                                         ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &PublicKey::from_secret_key(&self.secp_ctx, &htlc_base_key))))
1103                                                 },
1104                                                 Storage::Watchtower { ref revocation_base_key, ref htlc_base_key, .. } => {
1105                                                         (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, revocation_point, &revocation_base_key)),
1106                                                         ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &htlc_base_key)))
1107                                                 },
1108                                         };
1109                                         let a_htlc_key = match self.their_htlc_base_key {
1110                                                 None => return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs),
1111                                                 Some(their_htlc_base_key) => ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &their_htlc_base_key)),
1112                                         };
1113
1114                                         for (idx, outp) in tx.output.iter().enumerate() {
1115                                                 if outp.script_pubkey.is_v0_p2wpkh() {
1116                                                         match self.key_storage {
1117                                                                 Storage::Local { ref payment_base_key, .. } => {
1118                                                                         if let Ok(local_key) = chan_utils::derive_private_key(&self.secp_ctx, &revocation_point, &payment_base_key) {
1119                                                                                 spendable_outputs.push(SpendableOutputDescriptor::DynamicOutputP2WPKH {
1120                                                                                         outpoint: BitcoinOutPoint { txid: commitment_txid, vout: idx as u32 },
1121                                                                                         key: local_key,
1122                                                                                         output: outp.clone(),
1123                                                                                 });
1124                                                                         }
1125                                                                 },
1126                                                                 Storage::Watchtower { .. } => {}
1127                                                         }
1128                                                         break; // Only to_remote ouput is claimable
1129                                                 }
1130                                         }
1131
1132                                         let mut total_value = 0;
1133                                         let mut values = Vec::new();
1134                                         let mut inputs = Vec::new();
1135
1136                                         macro_rules! sign_input {
1137                                                 ($sighash_parts: expr, $input: expr, $amount: expr, $preimage: expr) => {
1138                                                         {
1139                                                                 let (sig, redeemscript) = match self.key_storage {
1140                                                                         Storage::Local { ref htlc_base_key, .. } => {
1141                                                                                 let htlc = &per_commitment_option.unwrap()[$input.sequence as usize];
1142                                                                                 let redeemscript = chan_utils::get_htlc_redeemscript_with_explicit_keys(htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey);
1143                                                                                 let sighash = ignore_error!(Message::from_slice(&$sighash_parts.sighash_all(&$input, &redeemscript, $amount)[..]));
1144                                                                                 let htlc_key = ignore_error!(chan_utils::derive_private_key(&self.secp_ctx, revocation_point, &htlc_base_key));
1145                                                                                 (self.secp_ctx.sign(&sighash, &htlc_key), redeemscript)
1146                                                                         },
1147                                                                         Storage::Watchtower { .. } => {
1148                                                                                 unimplemented!();
1149                                                                         }
1150                                                                 };
1151                                                                 $input.witness.push(sig.serialize_der(&self.secp_ctx).to_vec());
1152                                                                 $input.witness[0].push(SigHashType::All as u8);
1153                                                                 $input.witness.push($preimage);
1154                                                                 $input.witness.push(redeemscript.into_bytes());
1155                                                         }
1156                                                 }
1157                                         }
1158
1159                                         for (idx, htlc) in per_commitment_data.iter().enumerate() {
1160                                                 let expected_script = chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey);
1161                                                 if htlc.transaction_output_index as usize >= tx.output.len() ||
1162                                                                 tx.output[htlc.transaction_output_index as usize].value != htlc.amount_msat / 1000 ||
1163                                                                 tx.output[htlc.transaction_output_index as usize].script_pubkey != expected_script.to_v0_p2wsh() {
1164                                                         return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs); // Corrupted per_commitment_data, fuck this user
1165                                                 }
1166                                                 if let Some(payment_preimage) = self.payment_preimages.get(&htlc.payment_hash) {
1167                                                         let input = TxIn {
1168                                                                 previous_output: BitcoinOutPoint {
1169                                                                         txid: commitment_txid,
1170                                                                         vout: htlc.transaction_output_index,
1171                                                                 },
1172                                                                 script_sig: Script::new(),
1173                                                                 sequence: idx as u32, // reset to 0xfffffffd in sign_input
1174                                                                 witness: Vec::new(),
1175                                                         };
1176                                                         if htlc.cltv_expiry > height + CLTV_SHARED_CLAIM_BUFFER {
1177                                                                 inputs.push(input);
1178                                                                 values.push((tx.output[htlc.transaction_output_index as usize].value, payment_preimage));
1179                                                                 total_value += htlc.amount_msat / 1000;
1180                                                         } else {
1181                                                                 let mut single_htlc_tx = Transaction {
1182                                                                         version: 2,
1183                                                                         lock_time: 0,
1184                                                                         input: vec![input],
1185                                                                         output: vec!(TxOut {
1186                                                                                 script_pubkey: self.destination_script.clone(),
1187                                                                                 value: htlc.amount_msat / 1000, //TODO: - fee
1188                                                                         }),
1189                                                                 };
1190                                                                 let sighash_parts = bip143::SighashComponents::new(&single_htlc_tx);
1191                                                                 sign_input!(sighash_parts, single_htlc_tx.input[0], htlc.amount_msat / 1000, payment_preimage.to_vec());
1192                                                                 spendable_outputs.push(SpendableOutputDescriptor::StaticOutput {
1193                                                                         outpoint: BitcoinOutPoint { txid: single_htlc_tx.txid(), vout: 0 },
1194                                                                         output: single_htlc_tx.output[0].clone(),
1195                                                                 });
1196                                                                 txn_to_broadcast.push(single_htlc_tx);
1197                                                         }
1198                                                 }
1199                                         }
1200
1201                                         if inputs.is_empty() { return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs); } // Nothing to be done...probably a false positive/local tx
1202
1203                                         let outputs = vec!(TxOut {
1204                                                 script_pubkey: self.destination_script.clone(),
1205                                                 value: total_value, //TODO: - fee
1206                                         });
1207                                         let mut spend_tx = Transaction {
1208                                                 version: 2,
1209                                                 lock_time: 0,
1210                                                 input: inputs,
1211                                                 output: outputs,
1212                                         };
1213
1214                                         let mut values_drain = values.drain(..);
1215                                         let sighash_parts = bip143::SighashComponents::new(&spend_tx);
1216
1217                                         for input in spend_tx.input.iter_mut() {
1218                                                 let value = values_drain.next().unwrap();
1219                                                 sign_input!(sighash_parts, input, value.0, value.1.to_vec());
1220                                         }
1221
1222                                         spendable_outputs.push(SpendableOutputDescriptor::StaticOutput {
1223                                                 outpoint: BitcoinOutPoint { txid: spend_tx.txid(), vout: 0 },
1224                                                 output: spend_tx.output[0].clone(),
1225                                         });
1226                                         txn_to_broadcast.push(spend_tx);
1227                                 }
1228                         }
1229                 }
1230
1231                 (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs)
1232         }
1233
1234         /// Attempst to claim a remote HTLC-Success/HTLC-Timeout s outputs using the revocation key
1235         fn check_spend_remote_htlc(&self, tx: &Transaction, commitment_number: u64) -> (Option<Transaction>, Option<SpendableOutputDescriptor>) {
1236                 if tx.input.len() != 1 || tx.output.len() != 1 {
1237                         return (None, None)
1238                 }
1239
1240                 macro_rules! ignore_error {
1241                         ( $thing : expr ) => {
1242                                 match $thing {
1243                                         Ok(a) => a,
1244                                         Err(_) => return (None, None)
1245                                 }
1246                         };
1247                 }
1248
1249                 let secret = if let Some(secret) = self.get_secret(commitment_number) { secret } else { return (None, None); };
1250                 let per_commitment_key = ignore_error!(SecretKey::from_slice(&self.secp_ctx, &secret));
1251                 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1252                 let revocation_pubkey = match self.key_storage {
1253                         Storage::Local { ref revocation_base_key, .. } => {
1254                                 ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &PublicKey::from_secret_key(&self.secp_ctx, &revocation_base_key)))
1255                         },
1256                         Storage::Watchtower { ref revocation_base_key, .. } => {
1257                                 ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &revocation_base_key))
1258                         },
1259                 };
1260                 let delayed_key = match self.their_delayed_payment_base_key {
1261                         None => return (None, None),
1262                         Some(their_delayed_payment_base_key) => ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &their_delayed_payment_base_key)),
1263                 };
1264                 let redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.their_to_self_delay.unwrap(), &delayed_key);
1265                 let revokeable_p2wsh = redeemscript.to_v0_p2wsh();
1266                 let htlc_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
1267
1268                 let mut inputs = Vec::new();
1269                 let mut amount = 0;
1270
1271                 if tx.output[0].script_pubkey == revokeable_p2wsh { //HTLC transactions have one txin, one txout
1272                         inputs.push(TxIn {
1273                                 previous_output: BitcoinOutPoint {
1274                                         txid: htlc_txid,
1275                                         vout: 0,
1276                                 },
1277                                 script_sig: Script::new(),
1278                                 sequence: 0xfffffffd,
1279                                 witness: Vec::new(),
1280                         });
1281                         amount = tx.output[0].value;
1282                 }
1283
1284                 if !inputs.is_empty() {
1285                         let outputs = vec!(TxOut {
1286                                 script_pubkey: self.destination_script.clone(),
1287                                 value: amount, //TODO: - fee
1288                         });
1289
1290                         let mut spend_tx = Transaction {
1291                                 version: 2,
1292                                 lock_time: 0,
1293                                 input: inputs,
1294                                 output: outputs,
1295                         };
1296
1297                         let sighash_parts = bip143::SighashComponents::new(&spend_tx);
1298
1299                         let sig = match self.key_storage {
1300                                 Storage::Local { ref revocation_base_key, .. } => {
1301                                         let sighash = ignore_error!(Message::from_slice(&sighash_parts.sighash_all(&spend_tx.input[0], &redeemscript, amount)[..]));
1302                                         let revocation_key = ignore_error!(chan_utils::derive_private_revocation_key(&self.secp_ctx, &per_commitment_key, &revocation_base_key));
1303                                         self.secp_ctx.sign(&sighash, &revocation_key)
1304                                 }
1305                                 Storage::Watchtower { .. } => {
1306                                         unimplemented!();
1307                                 }
1308                         };
1309                         spend_tx.input[0].witness.push(sig.serialize_der(&self.secp_ctx).to_vec());
1310                         spend_tx.input[0].witness[0].push(SigHashType::All as u8);
1311                         spend_tx.input[0].witness.push(vec!(1));
1312                         spend_tx.input[0].witness.push(redeemscript.into_bytes());
1313
1314                         let outpoint = BitcoinOutPoint { txid: spend_tx.txid(), vout: 0 };
1315                         let output = spend_tx.output[0].clone();
1316                         (Some(spend_tx), Some(SpendableOutputDescriptor::StaticOutput { outpoint, output }))
1317                 } else { (None, None) }
1318         }
1319
1320         fn broadcast_by_local_state(&self, local_tx: &LocalSignedTx, per_commitment_point: &Option<PublicKey>, delayed_payment_base_key: &Option<SecretKey>) -> (Vec<Transaction>, Vec<SpendableOutputDescriptor>) {
1321                 let mut res = Vec::with_capacity(local_tx.htlc_outputs.len());
1322                 let mut spendable_outputs = Vec::with_capacity(local_tx.htlc_outputs.len());
1323
1324                 macro_rules! add_dynamic_output {
1325                         ($father_tx: expr, $vout: expr) => {
1326                                 if let Some(ref per_commitment_point) = *per_commitment_point {
1327                                         if let Some(ref delayed_payment_base_key) = *delayed_payment_base_key {
1328                                                 if let Ok(local_delayedkey) = chan_utils::derive_private_key(&self.secp_ctx, per_commitment_point, delayed_payment_base_key) {
1329                                                         spendable_outputs.push(SpendableOutputDescriptor::DynamicOutputP2WSH {
1330                                                                 outpoint: BitcoinOutPoint { txid: $father_tx.txid(), vout: $vout },
1331                                                                 key: local_delayedkey,
1332                                                                 witness_script: chan_utils::get_revokeable_redeemscript(&local_tx.revocation_key, self.our_to_self_delay, &local_tx.delayed_payment_key),
1333                                                                 to_self_delay: self.our_to_self_delay,
1334                                                                 output: $father_tx.output[$vout as usize].clone(),
1335                                                         });
1336                                                 }
1337                                         }
1338                                 }
1339                         }
1340                 }
1341
1342
1343                 let redeemscript = chan_utils::get_revokeable_redeemscript(&local_tx.revocation_key, self.their_to_self_delay.unwrap(), &local_tx.delayed_payment_key);
1344                 let revokeable_p2wsh = redeemscript.to_v0_p2wsh();
1345                 for (idx, output) in local_tx.tx.output.iter().enumerate() {
1346                         if output.script_pubkey == revokeable_p2wsh {
1347                                 add_dynamic_output!(local_tx.tx, idx as u32);
1348                                 break;
1349                         }
1350                 }
1351
1352                 for &(ref htlc, ref their_sig, ref our_sig) in local_tx.htlc_outputs.iter() {
1353                         if htlc.offered {
1354                                 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);
1355
1356                                 htlc_timeout_tx.input[0].witness.push(Vec::new()); // First is the multisig dummy
1357
1358                                 htlc_timeout_tx.input[0].witness.push(their_sig.serialize_der(&self.secp_ctx).to_vec());
1359                                 htlc_timeout_tx.input[0].witness[1].push(SigHashType::All as u8);
1360                                 htlc_timeout_tx.input[0].witness.push(our_sig.serialize_der(&self.secp_ctx).to_vec());
1361                                 htlc_timeout_tx.input[0].witness[2].push(SigHashType::All as u8);
1362
1363                                 htlc_timeout_tx.input[0].witness.push(Vec::new());
1364                                 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());
1365
1366                                 add_dynamic_output!(htlc_timeout_tx, 0);
1367                                 res.push(htlc_timeout_tx);
1368                         } else {
1369                                 if let Some(payment_preimage) = self.payment_preimages.get(&htlc.payment_hash) {
1370                                         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);
1371
1372                                         htlc_success_tx.input[0].witness.push(Vec::new()); // First is the multisig dummy
1373
1374                                         htlc_success_tx.input[0].witness.push(their_sig.serialize_der(&self.secp_ctx).to_vec());
1375                                         htlc_success_tx.input[0].witness[1].push(SigHashType::All as u8);
1376                                         htlc_success_tx.input[0].witness.push(our_sig.serialize_der(&self.secp_ctx).to_vec());
1377                                         htlc_success_tx.input[0].witness[2].push(SigHashType::All as u8);
1378
1379                                         htlc_success_tx.input[0].witness.push(payment_preimage.to_vec());
1380                                         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());
1381
1382                                         add_dynamic_output!(htlc_success_tx, 0);
1383                                         res.push(htlc_success_tx);
1384                                 }
1385                         }
1386                 }
1387
1388                 (res, spendable_outputs)
1389         }
1390
1391         /// Attempts to claim any claimable HTLCs in a commitment transaction which was not (yet)
1392         /// revoked using data in local_claimable_outpoints.
1393         /// Should not be used if check_spend_revoked_transaction succeeds.
1394         fn check_spend_local_transaction(&self, tx: &Transaction, _height: u32) -> (Vec<Transaction>, Vec<SpendableOutputDescriptor>) {
1395                 let commitment_txid = tx.txid();
1396                 if let &Some(ref local_tx) = &self.current_local_signed_commitment_tx {
1397                         if local_tx.txid == commitment_txid {
1398                                 match self.key_storage {
1399                                         Storage::Local { ref delayed_payment_base_key, ref latest_per_commitment_point, .. } => {
1400                                                 return self.broadcast_by_local_state(local_tx, latest_per_commitment_point, &Some(*delayed_payment_base_key));
1401                                         },
1402                                         Storage::Watchtower { .. } => {
1403                                                 return self.broadcast_by_local_state(local_tx, &None, &None);
1404                                         }
1405                                 }
1406                         }
1407                 }
1408                 if let &Some(ref local_tx) = &self.prev_local_signed_commitment_tx {
1409                         if local_tx.txid == commitment_txid {
1410                                 match self.key_storage {
1411                                         Storage::Local { ref delayed_payment_base_key, ref prev_latest_per_commitment_point, .. } => {
1412                                                 return self.broadcast_by_local_state(local_tx, prev_latest_per_commitment_point, &Some(*delayed_payment_base_key));
1413                                         },
1414                                         Storage::Watchtower { .. } => {
1415                                                 return self.broadcast_by_local_state(local_tx, &None, &None);
1416                                         }
1417                                 }
1418                         }
1419                 }
1420                 (Vec::new(), Vec::new())
1421         }
1422
1423         /// Generate a spendable output event when closing_transaction get registered onchain.
1424         fn check_spend_closing_transaction(&self, tx: &Transaction) -> Option<SpendableOutputDescriptor> {
1425                 if tx.input[0].sequence == 0xFFFFFFFF && !tx.input[0].witness.is_empty() && tx.input[0].witness.last().unwrap().len() == 71 {
1426                         match self.key_storage {
1427                                 Storage::Local { ref shutdown_pubkey, .. } =>  {
1428                                         let our_channel_close_key_hash = Hash160::from_data(&shutdown_pubkey.serialize());
1429                                         let shutdown_script = Builder::new().push_opcode(opcodes::All::OP_PUSHBYTES_0).push_slice(&our_channel_close_key_hash[..]).into_script();
1430                                         for (idx, output) in tx.output.iter().enumerate() {
1431                                                 if shutdown_script == output.script_pubkey {
1432                                                         return Some(SpendableOutputDescriptor::StaticOutput {
1433                                                                 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: idx as u32 },
1434                                                                 output: output.clone(),
1435                                                         });
1436                                                 }
1437                                         }
1438                                 }
1439                                 Storage::Watchtower { .. } => {
1440                                         //TODO: we need to ensure an offline client will generate the event when it
1441                                         // cames back online after only the watchtower saw the transaction
1442                                 }
1443                         }
1444                 }
1445                 None
1446         }
1447
1448         /// Used by ChannelManager deserialization to broadcast the latest local state if it's copy of
1449         /// the Channel was out-of-date.
1450         pub(super) fn get_latest_local_commitment_txn(&self) -> Vec<Transaction> {
1451                 if let &Some(ref local_tx) = &self.current_local_signed_commitment_tx {
1452                         let mut res = vec![local_tx.tx.clone()];
1453                         match self.key_storage {
1454                                 Storage::Local { ref delayed_payment_base_key, ref prev_latest_per_commitment_point, .. } => {
1455                                         res.append(&mut self.broadcast_by_local_state(local_tx, prev_latest_per_commitment_point, &Some(*delayed_payment_base_key)).0);
1456                                 },
1457                                 _ => panic!("Can only broadcast by local channelmonitor"),
1458                         };
1459                         res
1460                 } else {
1461                         Vec::new()
1462                 }
1463         }
1464
1465         fn block_connected(&mut self, txn_matched: &[&Transaction], height: u32, block_hash: &Sha256dHash, broadcaster: &BroadcasterInterface)-> (Vec<(Sha256dHash, Vec<TxOut>)>, Vec<SpendableOutputDescriptor>) {
1466                 let mut watch_outputs = Vec::new();
1467                 let mut spendable_outputs = Vec::new();
1468                 for tx in txn_matched {
1469                         if tx.input.len() == 1 {
1470                                 // Assuming our keys were not leaked (in which case we're screwed no matter what),
1471                                 // commitment transactions and HTLC transactions will all only ever have one input,
1472                                 // which is an easy way to filter out any potential non-matching txn for lazy
1473                                 // filters.
1474                                 let prevout = &tx.input[0].previous_output;
1475                                 let mut txn: Vec<Transaction> = Vec::new();
1476                                 let funding_txo = match self.key_storage {
1477                                         Storage::Local { ref funding_info, .. } => {
1478                                                 funding_info.clone()
1479                                         }
1480                                         Storage::Watchtower { .. } => {
1481                                                 unimplemented!();
1482                                         }
1483                                 };
1484                                 if funding_txo.is_none() || (prevout.txid == funding_txo.as_ref().unwrap().0.txid && prevout.vout == funding_txo.as_ref().unwrap().0.index as u32) {
1485                                         let (remote_txn, new_outputs, mut spendable_output) = self.check_spend_remote_transaction(tx, height);
1486                                         txn = remote_txn;
1487                                         spendable_outputs.append(&mut spendable_output);
1488                                         if !new_outputs.1.is_empty() {
1489                                                 watch_outputs.push(new_outputs);
1490                                         }
1491                                         if txn.is_empty() {
1492                                                 let (remote_txn, mut outputs) = self.check_spend_local_transaction(tx, height);
1493                                                 spendable_outputs.append(&mut outputs);
1494                                                 txn = remote_txn;
1495                                         }
1496                                         if !funding_txo.is_none() && txn.is_empty() {
1497                                                 if let Some(spendable_output) = self.check_spend_closing_transaction(tx) {
1498                                                         spendable_outputs.push(spendable_output);
1499                                                 }
1500                                         }
1501                                 } else {
1502                                         if let Some(&(commitment_number, _)) = self.remote_commitment_txn_on_chain.get(&prevout.txid) {
1503                                                 let (tx, spendable_output) = self.check_spend_remote_htlc(tx, commitment_number);
1504                                                 if let Some(tx) = tx {
1505                                                         txn.push(tx);
1506                                                 }
1507                                                 if let Some(spendable_output) = spendable_output {
1508                                                         spendable_outputs.push(spendable_output);
1509                                                 }
1510                                         }
1511                                 }
1512                                 for tx in txn.iter() {
1513                                         broadcaster.broadcast_transaction(tx);
1514                                 }
1515                         }
1516                 }
1517                 if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
1518                         if self.would_broadcast_at_height(height) {
1519                                 broadcaster.broadcast_transaction(&cur_local_tx.tx);
1520                                 match self.key_storage {
1521                                         Storage::Local { ref delayed_payment_base_key, ref latest_per_commitment_point, .. } => {
1522                                                 let (txs, mut outputs) = self.broadcast_by_local_state(&cur_local_tx, latest_per_commitment_point, &Some(*delayed_payment_base_key));
1523                                                 spendable_outputs.append(&mut outputs);
1524                                                 for tx in txs {
1525                                                         broadcaster.broadcast_transaction(&tx);
1526                                                 }
1527                                         },
1528                                         Storage::Watchtower { .. } => {
1529                                                 let (txs, mut outputs) = self.broadcast_by_local_state(&cur_local_tx, &None, &None);
1530                                                 spendable_outputs.append(&mut outputs);
1531                                                 for tx in txs {
1532                                                         broadcaster.broadcast_transaction(&tx);
1533                                                 }
1534                                         }
1535                                 }
1536                         }
1537                 }
1538                 self.last_block_hash = block_hash.clone();
1539                 (watch_outputs, spendable_outputs)
1540         }
1541
1542         pub(super) fn would_broadcast_at_height(&self, height: u32) -> bool {
1543                 if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
1544                         for &(ref htlc, _, _) in cur_local_tx.htlc_outputs.iter() {
1545                                 // For inbound HTLCs which we know the preimage for, we have to ensure we hit the
1546                                 // chain with enough room to claim the HTLC without our counterparty being able to
1547                                 // time out the HTLC first.
1548                                 // For outbound HTLCs which our counterparty hasn't failed/claimed, our primary
1549                                 // concern is being able to claim the corresponding inbound HTLC (on another
1550                                 // channel) before it expires. In fact, we don't even really care if our
1551                                 // counterparty here claims such an outbound HTLC after it expired as long as we
1552                                 // can still claim the corresponding HTLC. Thus, to avoid needlessly hitting the
1553                                 // chain when our counterparty is waiting for expiration to off-chain fail an HTLC
1554                                 // we give ourselves a few blocks of headroom after expiration before going
1555                                 // on-chain for an expired HTLC.
1556                                 // Note that, to avoid a potential attack whereby a node delays claiming an HTLC
1557                                 // from us until we've reached the point where we go on-chain with the
1558                                 // corresponding inbound HTLC, we must ensure that outbound HTLCs go on chain at
1559                                 // least CLTV_CLAIM_BUFFER blocks prior to the inbound HTLC.
1560                                 //  aka outbound_cltv + HTLC_FAIL_TIMEOUT_BLOCKS == height - CLTV_CLAIM_BUFFER
1561                                 //      inbound_cltv == height + CLTV_CLAIM_BUFFER
1562                                 //      outbound_cltv + HTLC_FAIL_TIMEOUT_BLOCKS + CLTV_CLAIM_BUFER <= inbound_cltv - CLTV_CLAIM_BUFFER
1563                                 //      HTLC_FAIL_TIMEOUT_BLOCKS + 2*CLTV_CLAIM_BUFER <= inbound_cltv - outbound_cltv
1564                                 //      HTLC_FAIL_TIMEOUT_BLOCKS + 2*CLTV_CLAIM_BUFER <= CLTV_EXPIRY_DELTA
1565                                 if ( htlc.offered && htlc.cltv_expiry + HTLC_FAIL_TIMEOUT_BLOCKS <= height) ||
1566                                    (!htlc.offered && htlc.cltv_expiry <= height + CLTV_CLAIM_BUFFER && self.payment_preimages.contains_key(&htlc.payment_hash)) {
1567                                         return true;
1568                                 }
1569                         }
1570                 }
1571                 false
1572         }
1573 }
1574
1575 const MAX_ALLOC_SIZE: usize = 64*1024;
1576
1577 impl<R: ::std::io::Read> ReadableArgs<R, Arc<Logger>> for (Sha256dHash, ChannelMonitor) {
1578         fn read(reader: &mut R, logger: Arc<Logger>) -> Result<Self, DecodeError> {
1579                 let secp_ctx = Secp256k1::new();
1580                 macro_rules! unwrap_obj {
1581                         ($key: expr) => {
1582                                 match $key {
1583                                         Ok(res) => res,
1584                                         Err(_) => return Err(DecodeError::InvalidValue),
1585                                 }
1586                         }
1587                 }
1588
1589                 let _ver: u8 = Readable::read(reader)?;
1590                 let min_ver: u8 = Readable::read(reader)?;
1591                 if min_ver > SERIALIZATION_VERSION {
1592                         return Err(DecodeError::UnknownVersion);
1593                 }
1594
1595                 let commitment_transaction_number_obscure_factor = <U48 as Readable<R>>::read(reader)?.0;
1596
1597                 let key_storage = match <u8 as Readable<R>>::read(reader)? {
1598                         0 => {
1599                                 let revocation_base_key = Readable::read(reader)?;
1600                                 let htlc_base_key = Readable::read(reader)?;
1601                                 let delayed_payment_base_key = Readable::read(reader)?;
1602                                 let payment_base_key = Readable::read(reader)?;
1603                                 let shutdown_pubkey = Readable::read(reader)?;
1604                                 let prev_latest_per_commitment_point = match <u8 as Readable<R>>::read(reader)? {
1605                                         0 => None,
1606                                         1 => Some(Readable::read(reader)?),
1607                                         _ => return Err(DecodeError::InvalidValue),
1608                                 };
1609                                 let latest_per_commitment_point = match <u8 as Readable<R>>::read(reader)? {
1610                                         0 => None,
1611                                         1 => Some(Readable::read(reader)?),
1612                                         _ => return Err(DecodeError::InvalidValue),
1613                                 };
1614                                 // Technically this can fail and serialize fail a round-trip, but only for serialization of
1615                                 // barely-init'd ChannelMonitors that we can't do anything with.
1616                                 let outpoint = OutPoint {
1617                                         txid: Readable::read(reader)?,
1618                                         index: Readable::read(reader)?,
1619                                 };
1620                                 let funding_info = Some((outpoint, Readable::read(reader)?));
1621                                 Storage::Local {
1622                                         revocation_base_key,
1623                                         htlc_base_key,
1624                                         delayed_payment_base_key,
1625                                         payment_base_key,
1626                                         shutdown_pubkey,
1627                                         prev_latest_per_commitment_point,
1628                                         latest_per_commitment_point,
1629                                         funding_info,
1630                                 }
1631                         },
1632                         _ => return Err(DecodeError::InvalidValue),
1633                 };
1634
1635                 let their_htlc_base_key = Some(Readable::read(reader)?);
1636                 let their_delayed_payment_base_key = Some(Readable::read(reader)?);
1637
1638                 let their_cur_revocation_points = {
1639                         let first_idx = <U48 as Readable<R>>::read(reader)?.0;
1640                         if first_idx == 0 {
1641                                 None
1642                         } else {
1643                                 let first_point = Readable::read(reader)?;
1644                                 let second_point_slice: [u8; 33] = Readable::read(reader)?;
1645                                 if second_point_slice[0..32] == [0; 32] && second_point_slice[32] == 0 {
1646                                         Some((first_idx, first_point, None))
1647                                 } else {
1648                                         Some((first_idx, first_point, Some(unwrap_obj!(PublicKey::from_slice(&secp_ctx, &second_point_slice)))))
1649                                 }
1650                         }
1651                 };
1652
1653                 let our_to_self_delay: u16 = Readable::read(reader)?;
1654                 let their_to_self_delay: Option<u16> = Some(Readable::read(reader)?);
1655
1656                 let mut old_secrets = [([0; 32], 1 << 48); 49];
1657                 for &mut (ref mut secret, ref mut idx) in old_secrets.iter_mut() {
1658                         *secret = Readable::read(reader)?;
1659                         *idx = Readable::read(reader)?;
1660                 }
1661
1662                 macro_rules! read_htlc_in_commitment {
1663                         () => {
1664                                 {
1665                                         let offered: bool = Readable::read(reader)?;
1666                                         let amount_msat: u64 = Readable::read(reader)?;
1667                                         let cltv_expiry: u32 = Readable::read(reader)?;
1668                                         let payment_hash: [u8; 32] = Readable::read(reader)?;
1669                                         let transaction_output_index: u32 = Readable::read(reader)?;
1670
1671                                         HTLCOutputInCommitment {
1672                                                 offered, amount_msat, cltv_expiry, payment_hash, transaction_output_index
1673                                         }
1674                                 }
1675                         }
1676                 }
1677
1678                 let remote_claimable_outpoints_len: u64 = Readable::read(reader)?;
1679                 let mut remote_claimable_outpoints = HashMap::with_capacity(cmp::min(remote_claimable_outpoints_len as usize, MAX_ALLOC_SIZE / 64));
1680                 for _ in 0..remote_claimable_outpoints_len {
1681                         let txid: Sha256dHash = Readable::read(reader)?;
1682                         let outputs_count: u64 = Readable::read(reader)?;
1683                         let mut outputs = Vec::with_capacity(cmp::min(outputs_count as usize, MAX_ALLOC_SIZE / 32));
1684                         for _ in 0..outputs_count {
1685                                 outputs.push(read_htlc_in_commitment!());
1686                         }
1687                         if let Some(_) = remote_claimable_outpoints.insert(txid, outputs) {
1688                                 return Err(DecodeError::InvalidValue);
1689                         }
1690                 }
1691
1692                 let remote_commitment_txn_on_chain_len: u64 = Readable::read(reader)?;
1693                 let mut remote_commitment_txn_on_chain = HashMap::with_capacity(cmp::min(remote_commitment_txn_on_chain_len as usize, MAX_ALLOC_SIZE / 32));
1694                 for _ in 0..remote_commitment_txn_on_chain_len {
1695                         let txid: Sha256dHash = Readable::read(reader)?;
1696                         let commitment_number = <U48 as Readable<R>>::read(reader)?.0;
1697                         let outputs_count = <u64 as Readable<R>>::read(reader)?;
1698                         let mut outputs = Vec::with_capacity(cmp::min(outputs_count as usize, MAX_ALLOC_SIZE / 8));
1699                         for _ in 0..outputs_count {
1700                                 outputs.push(Readable::read(reader)?);
1701                         }
1702                         if let Some(_) = remote_commitment_txn_on_chain.insert(txid, (commitment_number, outputs)) {
1703                                 return Err(DecodeError::InvalidValue);
1704                         }
1705                 }
1706
1707                 let remote_hash_commitment_number_len: u64 = Readable::read(reader)?;
1708                 let mut remote_hash_commitment_number = HashMap::with_capacity(cmp::min(remote_hash_commitment_number_len as usize, MAX_ALLOC_SIZE / 32));
1709                 for _ in 0..remote_hash_commitment_number_len {
1710                         let txid: [u8; 32] = Readable::read(reader)?;
1711                         let commitment_number = <U48 as Readable<R>>::read(reader)?.0;
1712                         if let Some(_) = remote_hash_commitment_number.insert(txid, commitment_number) {
1713                                 return Err(DecodeError::InvalidValue);
1714                         }
1715                 }
1716
1717                 macro_rules! read_local_tx {
1718                         () => {
1719                                 {
1720                                         let tx = match Transaction::consensus_decode(reader.by_ref()) {
1721                                                 Ok(tx) => tx,
1722                                                 Err(e) => match e {
1723                                                         encode::Error::Io(ioe) => return Err(DecodeError::Io(ioe)),
1724                                                         _ => return Err(DecodeError::InvalidValue),
1725                                                 },
1726                                         };
1727
1728                                         if tx.input.is_empty() {
1729                                                 // Ensure tx didn't hit the 0-input ambiguity case.
1730                                                 return Err(DecodeError::InvalidValue);
1731                                         }
1732
1733                                         let revocation_key = Readable::read(reader)?;
1734                                         let a_htlc_key = Readable::read(reader)?;
1735                                         let b_htlc_key = Readable::read(reader)?;
1736                                         let delayed_payment_key = Readable::read(reader)?;
1737                                         let feerate_per_kw: u64 = Readable::read(reader)?;
1738
1739                                         let htlc_outputs_len: u64 = Readable::read(reader)?;
1740                                         let mut htlc_outputs = Vec::with_capacity(cmp::min(htlc_outputs_len as usize, MAX_ALLOC_SIZE / 128));
1741                                         for _ in 0..htlc_outputs_len {
1742                                                 htlc_outputs.push((read_htlc_in_commitment!(), Readable::read(reader)?, Readable::read(reader)?));
1743                                         }
1744
1745                                         LocalSignedTx {
1746                                                 txid: tx.txid(),
1747                                                 tx, revocation_key, a_htlc_key, b_htlc_key, delayed_payment_key, feerate_per_kw, htlc_outputs
1748                                         }
1749                                 }
1750                         }
1751                 }
1752
1753                 let prev_local_signed_commitment_tx = match <u8 as Readable<R>>::read(reader)? {
1754                         0 => None,
1755                         1 => {
1756                                 Some(read_local_tx!())
1757                         },
1758                         _ => return Err(DecodeError::InvalidValue),
1759                 };
1760
1761                 let current_local_signed_commitment_tx = match <u8 as Readable<R>>::read(reader)? {
1762                         0 => None,
1763                         1 => {
1764                                 Some(read_local_tx!())
1765                         },
1766                         _ => return Err(DecodeError::InvalidValue),
1767                 };
1768
1769                 let current_remote_commitment_number = <U48 as Readable<R>>::read(reader)?.0;
1770
1771                 let payment_preimages_len: u64 = Readable::read(reader)?;
1772                 let mut payment_preimages = HashMap::with_capacity(cmp::min(payment_preimages_len as usize, MAX_ALLOC_SIZE / 32));
1773                 let mut sha = Sha256::new();
1774                 for _ in 0..payment_preimages_len {
1775                         let preimage: [u8; 32] = Readable::read(reader)?;
1776                         sha.reset();
1777                         sha.input(&preimage);
1778                         let mut hash = [0; 32];
1779                         sha.result(&mut hash);
1780                         if let Some(_) = payment_preimages.insert(hash, preimage) {
1781                                 return Err(DecodeError::InvalidValue);
1782                         }
1783                 }
1784
1785                 let last_block_hash: Sha256dHash = Readable::read(reader)?;
1786                 let destination_script = Readable::read(reader)?;
1787
1788                 Ok((last_block_hash.clone(), ChannelMonitor {
1789                         commitment_transaction_number_obscure_factor,
1790
1791                         key_storage,
1792                         their_htlc_base_key,
1793                         their_delayed_payment_base_key,
1794                         their_cur_revocation_points,
1795
1796                         our_to_self_delay,
1797                         their_to_self_delay,
1798
1799                         old_secrets,
1800                         remote_claimable_outpoints,
1801                         remote_commitment_txn_on_chain,
1802                         remote_hash_commitment_number,
1803
1804                         prev_local_signed_commitment_tx,
1805                         current_local_signed_commitment_tx,
1806                         current_remote_commitment_number,
1807
1808                         payment_preimages,
1809
1810                         destination_script,
1811                         last_block_hash,
1812                         secp_ctx,
1813                         logger,
1814                 }))
1815         }
1816
1817 }
1818
1819 #[cfg(test)]
1820 mod tests {
1821         use bitcoin::blockdata::script::Script;
1822         use bitcoin::blockdata::transaction::Transaction;
1823         use crypto::digest::Digest;
1824         use hex;
1825         use ln::channelmonitor::ChannelMonitor;
1826         use ln::chan_utils::{HTLCOutputInCommitment, TxCreationKeys};
1827         use util::sha2::Sha256;
1828         use util::test_utils::TestLogger;
1829         use secp256k1::key::{SecretKey,PublicKey};
1830         use secp256k1::{Secp256k1, Signature};
1831         use rand::{thread_rng,Rng};
1832         use std::sync::Arc;
1833
1834         #[test]
1835         fn test_per_commitment_storage() {
1836                 // Test vectors from BOLT 3:
1837                 let mut secrets: Vec<[u8; 32]> = Vec::new();
1838                 let mut monitor: ChannelMonitor;
1839                 let secp_ctx = Secp256k1::new();
1840                 let logger = Arc::new(TestLogger::new());
1841
1842                 macro_rules! test_secrets {
1843                         () => {
1844                                 let mut idx = 281474976710655;
1845                                 for secret in secrets.iter() {
1846                                         assert_eq!(monitor.get_secret(idx).unwrap(), *secret);
1847                                         idx -= 1;
1848                                 }
1849                                 assert_eq!(monitor.get_min_seen_secret(), idx + 1);
1850                                 assert!(monitor.get_secret(idx).is_none());
1851                         };
1852                 }
1853
1854                 {
1855                         // insert_secret correct sequence
1856                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[45; 32]).unwrap()), 0, Script::new(), logger.clone());
1857                         secrets.clear();
1858
1859                         secrets.push([0; 32]);
1860                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1861                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1862                         test_secrets!();
1863
1864                         secrets.push([0; 32]);
1865                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1866                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1867                         test_secrets!();
1868
1869                         secrets.push([0; 32]);
1870                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1871                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1872                         test_secrets!();
1873
1874                         secrets.push([0; 32]);
1875                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1876                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
1877                         test_secrets!();
1878
1879                         secrets.push([0; 32]);
1880                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
1881                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
1882                         test_secrets!();
1883
1884                         secrets.push([0; 32]);
1885                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
1886                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
1887                         test_secrets!();
1888
1889                         secrets.push([0; 32]);
1890                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
1891                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
1892                         test_secrets!();
1893
1894                         secrets.push([0; 32]);
1895                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
1896                         monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap();
1897                         test_secrets!();
1898                 }
1899
1900                 {
1901                         // insert_secret #1 incorrect
1902                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[45; 32]).unwrap()), 0, Script::new(), logger.clone());
1903                         secrets.clear();
1904
1905                         secrets.push([0; 32]);
1906                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
1907                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1908                         test_secrets!();
1909
1910                         secrets.push([0; 32]);
1911                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1912                         assert_eq!(monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap_err().0,
1913                                         "Previous secret did not match new one");
1914                 }
1915
1916                 {
1917                         // insert_secret #2 incorrect (#1 derived from incorrect)
1918                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[45; 32]).unwrap()), 0, Script::new(), logger.clone());
1919                         secrets.clear();
1920
1921                         secrets.push([0; 32]);
1922                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
1923                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1924                         test_secrets!();
1925
1926                         secrets.push([0; 32]);
1927                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("dddc3a8d14fddf2b68fa8c7fbad2748274937479dd0f8930d5ebb4ab6bd866a3").unwrap());
1928                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1929                         test_secrets!();
1930
1931                         secrets.push([0; 32]);
1932                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1933                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1934                         test_secrets!();
1935
1936                         secrets.push([0; 32]);
1937                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1938                         assert_eq!(monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap_err().0,
1939                                         "Previous secret did not match new one");
1940                 }
1941
1942                 {
1943                         // insert_secret #3 incorrect
1944                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[45; 32]).unwrap()), 0, Script::new(), logger.clone());
1945                         secrets.clear();
1946
1947                         secrets.push([0; 32]);
1948                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1949                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1950                         test_secrets!();
1951
1952                         secrets.push([0; 32]);
1953                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1954                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1955                         test_secrets!();
1956
1957                         secrets.push([0; 32]);
1958                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c51a18b13e8527e579ec56365482c62f180b7d5760b46e9477dae59e87ed423a").unwrap());
1959                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1960                         test_secrets!();
1961
1962                         secrets.push([0; 32]);
1963                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1964                         assert_eq!(monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap_err().0,
1965                                         "Previous secret did not match new one");
1966                 }
1967
1968                 {
1969                         // insert_secret #4 incorrect (1,2,3 derived from incorrect)
1970                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[45; 32]).unwrap()), 0, Script::new(), logger.clone());
1971                         secrets.clear();
1972
1973                         secrets.push([0; 32]);
1974                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
1975                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1976                         test_secrets!();
1977
1978                         secrets.push([0; 32]);
1979                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("dddc3a8d14fddf2b68fa8c7fbad2748274937479dd0f8930d5ebb4ab6bd866a3").unwrap());
1980                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1981                         test_secrets!();
1982
1983                         secrets.push([0; 32]);
1984                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c51a18b13e8527e579ec56365482c62f180b7d5760b46e9477dae59e87ed423a").unwrap());
1985                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1986                         test_secrets!();
1987
1988                         secrets.push([0; 32]);
1989                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("ba65d7b0ef55a3ba300d4e87af29868f394f8f138d78a7011669c79b37b936f4").unwrap());
1990                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
1991                         test_secrets!();
1992
1993                         secrets.push([0; 32]);
1994                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
1995                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
1996                         test_secrets!();
1997
1998                         secrets.push([0; 32]);
1999                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
2000                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
2001                         test_secrets!();
2002
2003                         secrets.push([0; 32]);
2004                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
2005                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
2006                         test_secrets!();
2007
2008                         secrets.push([0; 32]);
2009                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
2010                         assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap_err().0,
2011                                         "Previous secret did not match new one");
2012                 }
2013
2014                 {
2015                         // insert_secret #5 incorrect
2016                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[45; 32]).unwrap()), 0, Script::new(), logger.clone());
2017                         secrets.clear();
2018
2019                         secrets.push([0; 32]);
2020                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2021                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2022                         test_secrets!();
2023
2024                         secrets.push([0; 32]);
2025                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2026                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2027                         test_secrets!();
2028
2029                         secrets.push([0; 32]);
2030                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2031                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2032                         test_secrets!();
2033
2034                         secrets.push([0; 32]);
2035                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2036                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
2037                         test_secrets!();
2038
2039                         secrets.push([0; 32]);
2040                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("631373ad5f9ef654bb3dade742d09504c567edd24320d2fcd68e3cc47e2ff6a6").unwrap());
2041                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
2042                         test_secrets!();
2043
2044                         secrets.push([0; 32]);
2045                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
2046                         assert_eq!(monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap_err().0,
2047                                         "Previous secret did not match new one");
2048                 }
2049
2050                 {
2051                         // insert_secret #6 incorrect (5 derived from incorrect)
2052                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[45; 32]).unwrap()), 0, Script::new(), logger.clone());
2053                         secrets.clear();
2054
2055                         secrets.push([0; 32]);
2056                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2057                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2058                         test_secrets!();
2059
2060                         secrets.push([0; 32]);
2061                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2062                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2063                         test_secrets!();
2064
2065                         secrets.push([0; 32]);
2066                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2067                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2068                         test_secrets!();
2069
2070                         secrets.push([0; 32]);
2071                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2072                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
2073                         test_secrets!();
2074
2075                         secrets.push([0; 32]);
2076                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("631373ad5f9ef654bb3dade742d09504c567edd24320d2fcd68e3cc47e2ff6a6").unwrap());
2077                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
2078                         test_secrets!();
2079
2080                         secrets.push([0; 32]);
2081                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("b7e76a83668bde38b373970155c868a653304308f9896692f904a23731224bb1").unwrap());
2082                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
2083                         test_secrets!();
2084
2085                         secrets.push([0; 32]);
2086                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
2087                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
2088                         test_secrets!();
2089
2090                         secrets.push([0; 32]);
2091                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
2092                         assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap_err().0,
2093                                         "Previous secret did not match new one");
2094                 }
2095
2096                 {
2097                         // insert_secret #7 incorrect
2098                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[45; 32]).unwrap()), 0, Script::new(), logger.clone());
2099                         secrets.clear();
2100
2101                         secrets.push([0; 32]);
2102                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2103                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2104                         test_secrets!();
2105
2106                         secrets.push([0; 32]);
2107                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2108                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2109                         test_secrets!();
2110
2111                         secrets.push([0; 32]);
2112                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2113                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2114                         test_secrets!();
2115
2116                         secrets.push([0; 32]);
2117                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2118                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
2119                         test_secrets!();
2120
2121                         secrets.push([0; 32]);
2122                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
2123                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
2124                         test_secrets!();
2125
2126                         secrets.push([0; 32]);
2127                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
2128                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
2129                         test_secrets!();
2130
2131                         secrets.push([0; 32]);
2132                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("e7971de736e01da8ed58b94c2fc216cb1dca9e326f3a96e7194fe8ea8af6c0a3").unwrap());
2133                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
2134                         test_secrets!();
2135
2136                         secrets.push([0; 32]);
2137                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
2138                         assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap_err().0,
2139                                         "Previous secret did not match new one");
2140                 }
2141
2142                 {
2143                         // insert_secret #8 incorrect
2144                         monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[45; 32]).unwrap()), 0, Script::new(), logger.clone());
2145                         secrets.clear();
2146
2147                         secrets.push([0; 32]);
2148                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2149                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2150                         test_secrets!();
2151
2152                         secrets.push([0; 32]);
2153                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2154                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2155                         test_secrets!();
2156
2157                         secrets.push([0; 32]);
2158                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2159                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2160                         test_secrets!();
2161
2162                         secrets.push([0; 32]);
2163                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2164                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
2165                         test_secrets!();
2166
2167                         secrets.push([0; 32]);
2168                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
2169                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
2170                         test_secrets!();
2171
2172                         secrets.push([0; 32]);
2173                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
2174                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
2175                         test_secrets!();
2176
2177                         secrets.push([0; 32]);
2178                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
2179                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
2180                         test_secrets!();
2181
2182                         secrets.push([0; 32]);
2183                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a7efbc61aac46d34f77778bac22c8a20c6a46ca460addc49009bda875ec88fa4").unwrap());
2184                         assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap_err().0,
2185                                         "Previous secret did not match new one");
2186                 }
2187         }
2188
2189         #[test]
2190         fn test_prune_preimages() {
2191                 let secp_ctx = Secp256k1::new();
2192                 let logger = Arc::new(TestLogger::new());
2193                 let dummy_sig = Signature::from_der(&secp_ctx, &hex::decode("3045022100fa86fa9a36a8cd6a7bb8f06a541787d51371d067951a9461d5404de6b928782e02201c8b7c334c10aed8976a3a465be9a28abff4cb23acbf00022295b378ce1fa3cd").unwrap()[..]).unwrap();
2194
2195                 let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap());
2196                 macro_rules! dummy_keys {
2197                         () => {
2198                                 {
2199                                         TxCreationKeys {
2200                                                 per_commitment_point: dummy_key.clone(),
2201                                                 revocation_key: dummy_key.clone(),
2202                                                 a_htlc_key: dummy_key.clone(),
2203                                                 b_htlc_key: dummy_key.clone(),
2204                                                 a_delayed_payment_key: dummy_key.clone(),
2205                                                 b_payment_key: dummy_key.clone(),
2206                                         }
2207                                 }
2208                         }
2209                 }
2210                 let dummy_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
2211
2212                 let mut preimages = Vec::new();
2213                 {
2214                         let mut rng  = thread_rng();
2215                         for _ in 0..20 {
2216                                 let mut preimage = [0; 32];
2217                                 rng.fill_bytes(&mut preimage);
2218                                 let mut sha = Sha256::new();
2219                                 sha.input(&preimage);
2220                                 let mut hash = [0; 32];
2221                                 sha.result(&mut hash);
2222                                 preimages.push((preimage, hash));
2223                         }
2224                 }
2225
2226                 macro_rules! preimages_slice_to_htlc_outputs {
2227                         ($preimages_slice: expr) => {
2228                                 {
2229                                         let mut res = Vec::new();
2230                                         for (idx, preimage) in $preimages_slice.iter().enumerate() {
2231                                                 res.push(HTLCOutputInCommitment {
2232                                                         offered: true,
2233                                                         amount_msat: 0,
2234                                                         cltv_expiry: 0,
2235                                                         payment_hash: preimage.1.clone(),
2236                                                         transaction_output_index: idx as u32,
2237                                                 });
2238                                         }
2239                                         res
2240                                 }
2241                         }
2242                 }
2243                 macro_rules! preimages_to_local_htlcs {
2244                         ($preimages_slice: expr) => {
2245                                 {
2246                                         let mut inp = preimages_slice_to_htlc_outputs!($preimages_slice);
2247                                         let res: Vec<_> = inp.drain(..).map(|e| { (e, dummy_sig.clone(), dummy_sig.clone()) }).collect();
2248                                         res
2249                                 }
2250                         }
2251                 }
2252
2253                 macro_rules! test_preimages_exist {
2254                         ($preimages_slice: expr, $monitor: expr) => {
2255                                 for preimage in $preimages_slice {
2256                                         assert!($monitor.payment_preimages.contains_key(&preimage.1));
2257                                 }
2258                         }
2259                 }
2260
2261                 // Prune with one old state and a local commitment tx holding a few overlaps with the
2262                 // old state.
2263                 let mut monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[45; 32]).unwrap()), 0, Script::new(), logger.clone());
2264                 monitor.set_their_to_self_delay(10);
2265
2266                 monitor.provide_latest_local_commitment_tx_info(dummy_tx.clone(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..10]));
2267                 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[5..15]), 281474976710655, dummy_key);
2268                 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[15..20]), 281474976710654, dummy_key);
2269                 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[17..20]), 281474976710653, dummy_key);
2270                 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[18..20]), 281474976710652, dummy_key);
2271                 for &(ref preimage, ref hash) in preimages.iter() {
2272                         monitor.provide_payment_preimage(hash, preimage);
2273                 }
2274
2275                 // Now provide a secret, pruning preimages 10-15
2276                 let mut secret = [0; 32];
2277                 secret[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2278                 monitor.provide_secret(281474976710655, secret.clone()).unwrap();
2279                 assert_eq!(monitor.payment_preimages.len(), 15);
2280                 test_preimages_exist!(&preimages[0..10], monitor);
2281                 test_preimages_exist!(&preimages[15..20], monitor);
2282
2283                 // Now provide a further secret, pruning preimages 15-17
2284                 secret[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2285                 monitor.provide_secret(281474976710654, secret.clone()).unwrap();
2286                 assert_eq!(monitor.payment_preimages.len(), 13);
2287                 test_preimages_exist!(&preimages[0..10], monitor);
2288                 test_preimages_exist!(&preimages[17..20], monitor);
2289
2290                 // Now update local commitment tx info, pruning only element 18 as we still care about the
2291                 // previous commitment tx's preimages too
2292                 monitor.provide_latest_local_commitment_tx_info(dummy_tx.clone(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..5]));
2293                 secret[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2294                 monitor.provide_secret(281474976710653, secret.clone()).unwrap();
2295                 assert_eq!(monitor.payment_preimages.len(), 12);
2296                 test_preimages_exist!(&preimages[0..10], monitor);
2297                 test_preimages_exist!(&preimages[18..20], monitor);
2298
2299                 // But if we do it again, we'll prune 5-10
2300                 monitor.provide_latest_local_commitment_tx_info(dummy_tx.clone(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..3]));
2301                 secret[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2302                 monitor.provide_secret(281474976710652, secret.clone()).unwrap();
2303                 assert_eq!(monitor.payment_preimages.len(), 5);
2304                 test_preimages_exist!(&preimages[0..5], monitor);
2305         }
2306
2307         // Further testing is done in the ChannelManager integration tests.
2308 }