_ 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 latest ChannelMonitor must always be actively monitoring for chain updates (and no out-of-date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         ///
  75         /// Should also be used to indicate a failure to update the local copy of the channel monitor.
  76         PermanentFailure,
  77 }
  78
  79 /// General Err type for ChannelMonitor actions. Generally, this implies that the data provided is
  80 /// inconsistent with the ChannelMonitor being called. eg for ChannelMonitor::insert_combine this
  81 /// means you tried to merge two monitors for different channels or for a channel which was
  82 /// restored from a backup and then generated new commitment updates.
  83 /// Contains a human-readable error message.
  84 #[derive(Debug)]
  85 pub struct MonitorUpdateError(pub &'static str);
  86
  87 /// Simple trait indicating ability to track a set of ChannelMonitors and multiplex events between
  88 /// them. Generally should be implemented by keeping a local SimpleManyChannelMonitor and passing
  89 /// events to it, while also taking any add_update_monitor events and passing them to some remote
  90 /// server(s).
  91 ///
  92 /// Note that any updates to a channel's monitor *must* be applied to each instance of the
  93 /// channel's monitor everywhere (including remote watchtowers) *before* this function returns. If
  94 /// an update occurs and a remote watchtower is left with old state, it may broadcast transactions
  95 /// which we have revoked, allowing our counterparty to claim all funds in the channel!
  96 pub trait ManyChannelMonitor: Send + Sync {
  97         /// Adds or updates a monitor for the given `funding_txo`.
  98         ///
  99         /// Implementor must also ensure that the funding_txo outpoint is registered with any relevant
 100         /// ChainWatchInterfaces such that the provided monitor receives block_connected callbacks with
 101         /// any spends of it.
 102         fn add_update_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor) -> Result<(), ChannelMonitorUpdateErr>;
 103 }
 104
 105 /// A simple implementation of a ManyChannelMonitor and ChainListener. Can be used to create a
 106 /// watchtower or watch our own channels.
 107 ///
 108 /// Note that you must provide your own key by which to refer to channels.
 109 ///
 110 /// If you're accepting remote monitors (ie are implementing a watchtower), you must verify that
 111 /// users cannot overwrite a given channel by providing a duplicate key. ie you should probably
 112 /// index by a PublicKey which is required to sign any updates.
 113 ///
 114 /// If you're using this for local monitoring of your own channels, you probably want to use
 115 /// `OutPoint` as the key, which will give you a ManyChannelMonitor implementation.
 116 pub struct SimpleManyChannelMonitor<Key> {
 117         #[cfg(test)] // Used in ChannelManager tests to manipulate channels directly
 118         pub monitors: Mutex<HashMap<Key, ChannelMonitor>>,
 119         #[cfg(not(test))]
 120         monitors: Mutex<HashMap<Key, ChannelMonitor>>,
 121         chain_monitor: Arc<ChainWatchInterface>,
 122         broadcaster: Arc<BroadcasterInterface>,
 123         pending_events: Mutex<Vec<events::Event>>,
 124         logger: Arc<Logger>,
 125 }
 126
 127 impl<Key : Send + cmp::Eq + hash::Hash> ChainListener for SimpleManyChannelMonitor<Key> {
 128         fn block_connected(&self, header: &BlockHeader, height: u32, txn_matched: &[&Transaction], _indexes_of_txn_matched: &[u32]) {
 129                 let block_hash = header.bitcoin_hash();
 130                 let mut new_events: Vec<events::Event> = Vec::with_capacity(0);
 131                 {
 132                         let mut monitors = self.monitors.lock().unwrap();
 133                         for monitor in monitors.values_mut() {
 134                                 let (txn_outputs, spendable_outputs) = monitor.block_connected(txn_matched, height, &block_hash, &*self.broadcaster);
 135                                 if spendable_outputs.len() > 0 {
 136                                         new_events.push(events::Event::SpendableOutputs {
 137                                                 outputs: spendable_outputs,
 138                                         });
 139                                 }
 140                                 for (ref txid, ref outputs) in txn_outputs {
 141                                         for (idx, output) in outputs.iter().enumerate() {
 142                                                 self.chain_monitor.install_watch_outpoint((txid.clone(), idx as u32), &output.script_pubkey);
 143                                         }
 144                                 }
 145                         }
 146                 }
 147                 let mut pending_events = self.pending_events.lock().unwrap();
 148                 pending_events.append(&mut new_events);
 149         }
 150
 151         fn block_disconnected(&self, _: &BlockHeader) { }
 152 }
 153
 154 impl<Key : Send + cmp::Eq + hash::Hash + 'static> SimpleManyChannelMonitor<Key> {
 155         /// Creates a new object which can be used to monitor several channels given the chain
 156         /// interface with which to register to receive notifications.
 157         pub fn new(chain_monitor: Arc<ChainWatchInterface>, broadcaster: Arc<BroadcasterInterface>, logger: Arc<Logger>) -> Arc<SimpleManyChannelMonitor<Key>> {
 158                 let res = Arc::new(SimpleManyChannelMonitor {
 159                         monitors: Mutex::new(HashMap::new()),
 160                         chain_monitor,
 161                         broadcaster,
 162                         pending_events: Mutex::new(Vec::new()),
 163                         logger,
 164                 });
 165                 let weak_res = Arc::downgrade(&res);
 166                 res.chain_monitor.register_listener(weak_res);
 167                 res
 168         }
 169
 170         /// Adds or udpates the monitor which monitors the channel referred to by the given key.
 171         pub fn add_update_monitor_by_key(&self, key: Key, monitor: ChannelMonitor) -> Result<(), MonitorUpdateError> {
 172                 let mut monitors = self.monitors.lock().unwrap();
 173                 match monitors.get_mut(&key) {
 174                         Some(orig_monitor) => {
 175                                 log_trace!(self, "Updating Channel Monitor for channel {}", log_funding_info!(monitor.key_storage));
 176                                 return orig_monitor.insert_combine(monitor);
 177                         },
 178                         None => {}
 179                 };
 180                 match monitor.key_storage {
 181                         Storage::Local { ref funding_info, .. } => {
 182                                 match funding_info {
 183                                         &None => {
 184                                                 return Err(MonitorUpdateError("Try to update a useless monitor without funding_txo !"));
 185                                         },
 186                                         &Some((ref outpoint, ref script)) => {
 187                                                 log_trace!(self, "Got new Channel Monitor for channel {}", log_bytes!(outpoint.to_channel_id()[..]));
 188                                                 self.chain_monitor.install_watch_tx(&outpoint.txid, script);
 189                                                 self.chain_monitor.install_watch_outpoint((outpoint.txid, outpoint.index as u32), script);
 190                                         },
 191                                 }
 192                         },
 193                         Storage::Watchtower { .. } => {
 194                                 self.chain_monitor.watch_all_txn();
 195                         }
 196                 }
 197                 monitors.insert(key, monitor);
 198                 Ok(())
 199         }
 200 }
 201
 202 impl ManyChannelMonitor for SimpleManyChannelMonitor<OutPoint> {
 203         fn add_update_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor) -> Result<(), ChannelMonitorUpdateErr> {
 204                 match self.add_update_monitor_by_key(funding_txo, monitor) {
 205                         Ok(_) => Ok(()),
 206                         Err(_) => Err(ChannelMonitorUpdateErr::PermanentFailure),
 207                 }
 208         }
 209 }
 210
 211 impl<Key : Send + cmp::Eq + hash::Hash> events::EventsProvider for SimpleManyChannelMonitor<Key> {
 212         fn get_and_clear_pending_events(&self) -> Vec<events::Event> {
 213                 let mut pending_events = self.pending_events.lock().unwrap();
 214                 let mut ret = Vec::new();
 215                 mem::swap(&mut ret, &mut *pending_events);
 216                 ret
 217         }
 218 }
 219
 220 /// If an HTLC expires within this many blocks, don't try to claim it in a shared transaction,
 221 /// instead claiming it in its own individual transaction.
 222 const CLTV_SHARED_CLAIM_BUFFER: u32 = 12;
 223 /// If an HTLC expires within this many blocks, force-close the channel to broadcast the
 224 /// HTLC-Success transaction.
 225 /// In other words, this is an upper bound on how many blocks we think it can take us to get a
 226 /// transaction confirmed (and we use it in a few more, equivalent, places).
 227 pub(crate) const CLTV_CLAIM_BUFFER: u32 = 6;
 228 /// Number of blocks by which point we expect our counterparty to have seen new blocks on the
 229 /// network and done a full update_fail_htlc/commitment_signed dance (+ we've updated all our
 230 /// copies of ChannelMonitors, including watchtowers).
 231 pub(crate) const HTLC_FAIL_TIMEOUT_BLOCKS: u32 = 3;
 232
 233 #[derive(Clone, PartialEq)]
 234 enum Storage {
 235         Local {
 236                 revocation_base_key: SecretKey,
 237                 htlc_base_key: SecretKey,
 238                 delayed_payment_base_key: SecretKey,
 239                 payment_base_key: SecretKey,
 240                 shutdown_pubkey: PublicKey,
 241                 prev_latest_per_commitment_point: Option<PublicKey>,
 242                 latest_per_commitment_point: Option<PublicKey>,
 243                 funding_info: Option<(OutPoint, Script)>,
 244         },
 245         Watchtower {
 246                 revocation_base_key: PublicKey,
 247                 htlc_base_key: PublicKey,
 248         }
 249 }
 250
 251 #[derive(Clone, PartialEq)]
 252 struct LocalSignedTx {
 253         /// txid of the transaction in tx, just used to make comparison faster
 254         txid: Sha256dHash,
 255         tx: Transaction,
 256         revocation_key: PublicKey,
 257         a_htlc_key: PublicKey,
 258         b_htlc_key: PublicKey,
 259         delayed_payment_key: PublicKey,
 260         feerate_per_kw: u64,
 261         htlc_outputs: Vec<(HTLCOutputInCommitment, Signature, Signature)>,
 262 }
 263
 264 const SERIALIZATION_VERSION: u8 = 1;
 265 const MIN_SERIALIZATION_VERSION: u8 = 1;
 266
 267 /// A ChannelMonitor handles chain events (blocks connected and disconnected) and generates
 268 /// on-chain transactions to ensure no loss of funds occurs.
 269 ///
 270 /// You MUST ensure that no ChannelMonitors for a given channel anywhere contain out-of-date
 271 /// information and are actively monitoring the chain.
 272 #[derive(Clone)]
 273 pub struct ChannelMonitor {
 274         commitment_transaction_number_obscure_factor: u64,
 275
 276         key_storage: Storage,
 277         their_htlc_base_key: Option<PublicKey>,
 278         their_delayed_payment_base_key: Option<PublicKey>,
 279         // first is the idx of the first of the two revocation points
 280         their_cur_revocation_points: Option<(u64, PublicKey, Option<PublicKey>)>,
 281
 282         our_to_self_delay: u16,
 283         their_to_self_delay: Option<u16>,
 284
 285         old_secrets: [([u8; 32], u64); 49],
 286         remote_claimable_outpoints: HashMap<Sha256dHash, Vec<HTLCOutputInCommitment>>,
 287         /// We cannot identify HTLC-Success or HTLC-Timeout transactions by themselves on the chain.
 288         /// Nor can we figure out their commitment numbers without the commitment transaction they are
 289         /// spending. Thus, in order to claim them via revocation key, we track all the remote
 290         /// commitment transactions which we find on-chain, mapping them to the commitment number which
 291         /// can be used to derive the revocation key and claim the transactions.
 292         remote_commitment_txn_on_chain: HashMap<Sha256dHash, (u64, Vec<Script>)>,
 293         /// Cache used to make pruning of payment_preimages faster.
 294         /// Maps payment_hash values to commitment numbers for remote transactions for non-revoked
 295         /// remote transactions (ie should remain pretty small).
 296         /// Serialized to disk but should generally not be sent to Watchtowers.
 297         remote_hash_commitment_number: HashMap<[u8; 32], u64>,
 298
 299         // We store two local commitment transactions to avoid any race conditions where we may update
 300         // some monitors (potentially on watchtowers) but then fail to update others, resulting in the
 301         // various monitors for one channel being out of sync, and us broadcasting a local
 302         // transaction for which we have deleted claim information on some watchtowers.
 303         prev_local_signed_commitment_tx: Option<LocalSignedTx>,
 304         current_local_signed_commitment_tx: Option<LocalSignedTx>,
 305
 306         // Used just for ChannelManager to make sure it has the latest channel data during
 307         // deserialization
 308         current_remote_commitment_number: u64,
 309
 310         payment_preimages: HashMap<[u8; 32], [u8; 32]>,
 311
 312         destination_script: Script,
 313
 314         // We simply modify last_block_hash in Channel's block_connected so that serialization is
 315         // consistent but hopefully the users' copy handles block_connected in a consistent way.
 316         // (we do *not*, however, update them in insert_combine to ensure any local user copies keep
 317         // their last_block_hash from its state and not based on updated copies that didn't run through
 318         // the full block_connected).
 319         pub(crate) last_block_hash: Sha256dHash,
 320         secp_ctx: Secp256k1<secp256k1::All>, //TODO: dedup this a bit...
 321         logger: Arc<Logger>,
 322 }
 323
 324 #[cfg(any(test, feature = "fuzztarget"))]
 325 /// Used only in testing and fuzztarget to check serialization roundtrips don't change the
 326 /// underlying object
 327 impl PartialEq for ChannelMonitor {
 328         fn eq(&self, other: &Self) -> bool {
 329                 if self.commitment_transaction_number_obscure_factor != other.commitment_transaction_number_obscure_factor ||
 330                         self.key_storage != other.key_storage ||
 331                         self.their_htlc_base_key != other.their_htlc_base_key ||
 332                         self.their_delayed_payment_base_key != other.their_delayed_payment_base_key ||
 333                         self.their_cur_revocation_points != other.their_cur_revocation_points ||
 334                         self.our_to_self_delay != other.our_to_self_delay ||
 335                         self.their_to_self_delay != other.their_to_self_delay ||
 336                         self.remote_claimable_outpoints != other.remote_claimable_outpoints ||
 337                         self.remote_commitment_txn_on_chain != other.remote_commitment_txn_on_chain ||
 338                         self.remote_hash_commitment_number != other.remote_hash_commitment_number ||
 339                         self.prev_local_signed_commitment_tx != other.prev_local_signed_commitment_tx ||
 340                         self.current_remote_commitment_number != other.current_remote_commitment_number ||
 341                         self.current_local_signed_commitment_tx != other.current_local_signed_commitment_tx ||
 342                         self.payment_preimages != other.payment_preimages ||
 343                         self.destination_script != other.destination_script
 344                 {
 345                         false
 346                 } else {
 347                         for (&(ref secret, ref idx), &(ref o_secret, ref o_idx)) in self.old_secrets.iter().zip(other.old_secrets.iter()) {
 348                                 if secret != o_secret || idx != o_idx {
 349                                         return false
 350                                 }
 351                         }
 352                         true
 353                 }
 354         }
 355 }
 356
 357 impl ChannelMonitor {
 358         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 {
 359                 ChannelMonitor {
 360                         commitment_transaction_number_obscure_factor: 0,
 361
 362                         key_storage: Storage::Local {
 363                                 revocation_base_key: revocation_base_key.clone(),
 364                                 htlc_base_key: htlc_base_key.clone(),
 365                                 delayed_payment_base_key: delayed_payment_base_key.clone(),
 366                                 payment_base_key: payment_base_key.clone(),
 367                                 shutdown_pubkey: shutdown_pubkey.clone(),
 368                                 prev_latest_per_commitment_point: None,
 369                                 latest_per_commitment_point: None,
 370                                 funding_info: None,
 371                         },
 372                         their_htlc_base_key: None,
 373                         their_delayed_payment_base_key: None,
 374                         their_cur_revocation_points: None,
 375
 376                         our_to_self_delay: our_to_self_delay,
 377                         their_to_self_delay: None,
 378
 379                         old_secrets: [([0; 32], 1 << 48); 49],
 380                         remote_claimable_outpoints: HashMap::new(),
 381                         remote_commitment_txn_on_chain: HashMap::new(),
 382                         remote_hash_commitment_number: HashMap::new(),
 383
 384                         prev_local_signed_commitment_tx: None,
 385                         current_local_signed_commitment_tx: None,
 386                         current_remote_commitment_number: 1 << 48,
 387
 388                         payment_preimages: HashMap::new(),
 389                         destination_script: destination_script,
 390
 391                         last_block_hash: Default::default(),
 392                         secp_ctx: Secp256k1::new(),
 393                         logger,
 394                 }
 395         }
 396
 397         #[inline]
 398         fn place_secret(idx: u64) -> u8 {
 399                 for i in 0..48 {
 400                         if idx & (1 << i) == (1 << i) {
 401                                 return i
 402                         }
 403                 }
 404                 48
 405         }
 406
 407         #[inline]
 408         fn derive_secret(secret: [u8; 32], bits: u8, idx: u64) -> [u8; 32] {
 409                 let mut res: [u8; 32] = secret;
 410                 for i in 0..bits {
 411                         let bitpos = bits - 1 - i;
 412                         if idx & (1 << bitpos) == (1 << bitpos) {
 413                                 res[(bitpos / 8) as usize] ^= 1 << (bitpos & 7);
 414                                 let mut sha = Sha256::new();
 415                                 sha.input(&res);
 416                                 sha.result(&mut res);
 417                         }
 418                 }
 419                 res
 420         }
 421
 422         /// Inserts a revocation secret into this channel monitor. Prunes old preimages if neither
 423         /// needed by local commitment transactions HTCLs nor by remote ones. Unless we haven't already seen remote
 424         /// commitment transaction's secret, they are de facto pruned (we can use revocation key).
 425         pub(super) fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), MonitorUpdateError> {
 426                 let pos = ChannelMonitor::place_secret(idx);
 427                 for i in 0..pos {
 428                         let (old_secret, old_idx) = self.old_secrets[i as usize];
 429                         if ChannelMonitor::derive_secret(secret, pos, old_idx) != old_secret {
 430                                 return Err(MonitorUpdateError("Previous secret did not match new one"));
 431                         }
 432                 }
 433                 self.old_secrets[pos as usize] = (secret, idx);
 434
 435                 if !self.payment_preimages.is_empty() {
 436                         let local_signed_commitment_tx = self.current_local_signed_commitment_tx.as_ref().expect("Channel needs at least an initial commitment tx !");
 437                         let prev_local_signed_commitment_tx = self.prev_local_signed_commitment_tx.as_ref();
 438                         let min_idx = self.get_min_seen_secret();
 439                         let remote_hash_commitment_number = &mut self.remote_hash_commitment_number;
 440
 441                         self.payment_preimages.retain(|&k, _| {
 442                                 for &(ref htlc, _, _) in &local_signed_commitment_tx.htlc_outputs {
 443                                         if k == htlc.payment_hash {
 444                                                 return true
 445                                         }
 446                                 }
 447                                 if let Some(prev_local_commitment_tx) = prev_local_signed_commitment_tx {
 448                                         for &(ref htlc, _, _) in prev_local_commitment_tx.htlc_outputs.iter() {
 449                                                 if k == htlc.payment_hash {
 450                                                         return true
 451                                                 }
 452                                         }
 453                                 }
 454                                 let contains = if let Some(cn) = remote_hash_commitment_number.get(&k) {
 455                                         if *cn < min_idx {
 456                                                 return true
 457                                         }
 458                                         true
 459                                 } else { false };
 460                                 if contains {
 461                                         remote_hash_commitment_number.remove(&k);
 462                                 }
 463                                 false
 464                         });
 465                 }
 466
 467                 Ok(())
 468         }
 469
 470         /// Informs this monitor of the latest remote (ie non-broadcastable) commitment transaction.
 471         /// The monitor watches for it to be broadcasted and then uses the HTLC information (and
 472         /// possibly future revocation/preimage information) to claim outputs where possible.
 473         /// We cache also the mapping hash:commitment number to lighten pruning of old preimages by watchtowers.
 474         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) {
 475                 // TODO: Encrypt the htlc_outputs data with the single-hash of the commitment transaction
 476                 // so that a remote monitor doesn't learn anything unless there is a malicious close.
 477                 // (only maybe, sadly we cant do the same for local info, as we need to be aware of
 478                 // timeouts)
 479                 for htlc in &htlc_outputs {
 480                         self.remote_hash_commitment_number.insert(htlc.payment_hash, commitment_number);
 481                 }
 482                 self.remote_claimable_outpoints.insert(unsigned_commitment_tx.txid(), htlc_outputs);
 483                 self.current_remote_commitment_number = commitment_number;
 484                 //TODO: Merge this into the other per-remote-transaction output storage stuff
 485                 match self.their_cur_revocation_points {
 486                         Some(old_points) => {
 487                                 if old_points.0 == commitment_number + 1 {
 488                                         self.their_cur_revocation_points = Some((old_points.0, old_points.1, Some(their_revocation_point)));
 489                                 } else if old_points.0 == commitment_number + 2 {
 490                                         if let Some(old_second_point) = old_points.2 {
 491                                                 self.their_cur_revocation_points = Some((old_points.0 - 1, old_second_point, Some(their_revocation_point)));
 492                                         } else {
 493                                                 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
 494                                         }
 495                                 } else {
 496                                         self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
 497                                 }
 498                         },
 499                         None => {
 500                                 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
 501                         }
 502                 }
 503         }
 504
 505         /// Informs this monitor of the latest local (ie broadcastable) commitment transaction. The
 506         /// monitor watches for timeouts and may broadcast it if we approach such a timeout. Thus, it
 507         /// is important that any clones of this channel monitor (including remote clones) by kept
 508         /// up-to-date as our local commitment transaction is updated.
 509         /// Panics if set_their_to_self_delay has never been called.
 510         /// Also update Storage with latest local per_commitment_point to derive local_delayedkey in
 511         /// case of onchain HTLC tx
 512         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)>) {
 513                 assert!(self.their_to_self_delay.is_some());
 514                 self.prev_local_signed_commitment_tx = self.current_local_signed_commitment_tx.take();
 515                 self.current_local_signed_commitment_tx = Some(LocalSignedTx {
 516                         txid: signed_commitment_tx.txid(),
 517                         tx: signed_commitment_tx,
 518                         revocation_key: local_keys.revocation_key,
 519                         a_htlc_key: local_keys.a_htlc_key,
 520                         b_htlc_key: local_keys.b_htlc_key,
 521                         delayed_payment_key: local_keys.a_delayed_payment_key,
 522                         feerate_per_kw,
 523                         htlc_outputs,
 524                 });
 525
 526                 if let Storage::Local { ref mut latest_per_commitment_point, .. } = self.key_storage {
 527                         *latest_per_commitment_point = Some(local_keys.per_commitment_point);
 528                 } else {
 529                         panic!("Channel somehow ended up with its internal ChannelMonitor being in Watchtower mode?");
 530                 }
 531         }
 532
 533         /// Provides a payment_hash->payment_preimage mapping. Will be automatically pruned when all
 534         /// commitment_tx_infos which contain the payment hash have been revoked.
 535         pub(super) fn provide_payment_preimage(&mut self, payment_hash: &[u8; 32], payment_preimage: &[u8; 32]) {
 536                 self.payment_preimages.insert(payment_hash.clone(), payment_preimage.clone());
 537         }
 538
 539         /// Combines this ChannelMonitor with the information contained in the other ChannelMonitor.
 540         /// After a successful call this ChannelMonitor is up-to-date and is safe to use to monitor the
 541         /// chain for new blocks/transactions.
 542         pub fn insert_combine(&mut self, mut other: ChannelMonitor) -> Result<(), MonitorUpdateError> {
 543                 match self.key_storage {
 544                         Storage::Local { ref funding_info, .. } => {
 545                                 if funding_info.is_none() { return Err(MonitorUpdateError("Try to combine a Local monitor without funding_info")); }
 546                                 let our_funding_info = funding_info;
 547                                 if let Storage::Local { ref funding_info, .. } = other.key_storage {
 548                                         if funding_info.is_none() { return Err(MonitorUpdateError("Try to combine a Local monitor without funding_info")); }
 549                                         // We should be able to compare the entire funding_txo, but in fuzztarget its trivially
 550                                         // easy to collide the funding_txo hash and have a different scriptPubKey.
 551                                         if funding_info.as_ref().unwrap().0 != our_funding_info.as_ref().unwrap().0 {
 552                                                 return Err(MonitorUpdateError("Funding transaction outputs are not identical!"));
 553                                         }
 554                                 } else {
 555                                         return Err(MonitorUpdateError("Try to combine a Local monitor with a Watchtower one !"));
 556                                 }
 557                         },
 558                         Storage::Watchtower { .. } => {
 559                                 if let Storage::Watchtower { .. } = other.key_storage {
 560                                         unimplemented!();
 561                                 } else {
 562                                         return Err(MonitorUpdateError("Try to combine a Watchtower monitor with a Local one !"));
 563                                 }
 564                         },
 565                 }
 566                 let other_min_secret = other.get_min_seen_secret();
 567                 let our_min_secret = self.get_min_seen_secret();
 568                 if our_min_secret > other_min_secret {
 569                         self.provide_secret(other_min_secret, other.get_secret(other_min_secret).unwrap())?;
 570                 }
 571                 if let Some(ref local_tx) = self.current_local_signed_commitment_tx {
 572                         if let Some(ref other_local_tx) = other.current_local_signed_commitment_tx {
 573                                 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);
 574                                 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);
 575                                 if our_commitment_number >= other_commitment_number {
 576                                         self.key_storage = other.key_storage;
 577                                 }
 578                         }
 579                 }
 580                 // TODO: We should use current_remote_commitment_number and the commitment number out of
 581                 // local transactions to decide how to merge
 582                 if our_min_secret >= other_min_secret {
 583                         self.their_cur_revocation_points = other.their_cur_revocation_points;
 584                         for (txid, htlcs) in other.remote_claimable_outpoints.drain() {
 585                                 self.remote_claimable_outpoints.insert(txid, htlcs);
 586                         }
 587                         if let Some(local_tx) = other.prev_local_signed_commitment_tx {
 588                                 self.prev_local_signed_commitment_tx = Some(local_tx);
 589                         }
 590                         if let Some(local_tx) = other.current_local_signed_commitment_tx {
 591                                 self.current_local_signed_commitment_tx = Some(local_tx);
 592                         }
 593                         self.payment_preimages = other.payment_preimages;
 594                 }
 595
 596                 self.current_remote_commitment_number = cmp::min(self.current_remote_commitment_number, other.current_remote_commitment_number);
 597                 Ok(())
 598         }
 599
 600         /// Panics if commitment_transaction_number_obscure_factor doesn't fit in 48 bits
 601         pub(super) fn set_commitment_obscure_factor(&mut self, commitment_transaction_number_obscure_factor: u64) {
 602                 assert!(commitment_transaction_number_obscure_factor < (1 << 48));
 603                 self.commitment_transaction_number_obscure_factor = commitment_transaction_number_obscure_factor;
 604         }
 605
 606         /// Allows this monitor to scan only for transactions which are applicable. Note that this is
 607         /// optional, without it this monitor cannot be used in an SPV client, but you may wish to
 608         /// avoid this (or call unset_funding_info) on a monitor you wish to send to a watchtower as it
 609         /// provides slightly better privacy.
 610         /// It's the responsibility of the caller to register outpoint and script with passing the former
 611         /// value as key to add_update_monitor.
 612         pub(super) fn set_funding_info(&mut self, new_funding_info: (OutPoint, Script)) {
 613                 match self.key_storage {
 614                         Storage::Local { ref mut funding_info, .. } => {
 615                                 *funding_info = Some(new_funding_info);
 616                         },
 617                         Storage::Watchtower { .. } => {
 618                                 panic!("Channel somehow ended up with its internal ChannelMonitor being in Watchtower mode?");
 619                         }
 620                 }
 621         }
 622
 623         /// We log these base keys at channel opening to being able to rebuild redeemscript in case of leaked revoked commit tx
 624         pub(super) fn set_their_base_keys(&mut self, their_htlc_base_key: &PublicKey, their_delayed_payment_base_key: &PublicKey) {
 625                 self.their_htlc_base_key = Some(their_htlc_base_key.clone());
 626                 self.their_delayed_payment_base_key = Some(their_delayed_payment_base_key.clone());
 627         }
 628
 629         pub(super) fn set_their_to_self_delay(&mut self, their_to_self_delay: u16) {
 630                 self.their_to_self_delay = Some(their_to_self_delay);
 631         }
 632
 633         pub(super) fn unset_funding_info(&mut self) {
 634                 match self.key_storage {
 635                         Storage::Local { ref mut funding_info, .. } => {
 636                                 *funding_info = None;
 637                         },
 638                         Storage::Watchtower { .. } => {
 639                                 panic!("Channel somehow ended up with its internal ChannelMonitor being in Watchtower mode?");
 640                         },
 641                 }
 642         }
 643
 644         /// Gets the funding transaction outpoint of the channel this ChannelMonitor is monitoring for.
 645         pub fn get_funding_txo(&self) -> Option<OutPoint> {
 646                 match self.key_storage {
 647                         Storage::Local { ref funding_info, .. } => {
 648                                 match funding_info {
 649                                         &Some((outpoint, _)) => Some(outpoint),
 650                                         &None => None
 651                                 }
 652                         },
 653                         Storage::Watchtower { .. } => {
 654                                 return None;
 655                         }
 656                 }
 657         }
 658
 659         /// Gets the sets of all outpoints which this ChannelMonitor expects to hear about spends of.
 660         /// Generally useful when deserializing as during normal operation the return values of
 661         /// block_connected are sufficient to ensure all relevant outpoints are being monitored (note
 662         /// that the get_funding_txo outpoint and transaction must also be monitored for!).
 663         pub fn get_monitored_outpoints(&self) -> Vec<(Sha256dHash, u32, &Script)> {
 664                 let mut res = Vec::with_capacity(self.remote_commitment_txn_on_chain.len() * 2);
 665                 for (ref txid, &(_, ref outputs)) in self.remote_commitment_txn_on_chain.iter() {
 666                         for (idx, output) in outputs.iter().enumerate() {
 667                                 res.push(((*txid).clone(), idx as u32, output));
 668                         }
 669                 }
 670                 res
 671         }
 672
 673         /// Serializes into a vec, with various modes for the exposed pub fns
 674         fn write<W: Writer>(&self, writer: &mut W, for_local_storage: bool) -> Result<(), ::std::io::Error> {
 675                 //TODO: We still write out all the serialization here manually instead of using the fancy
 676                 //serialization framework we have, we should migrate things over to it.
 677                 writer.write_all(&[SERIALIZATION_VERSION; 1])?;
 678                 writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
 679
 680                 // Set in initial Channel-object creation, so should always be set by now:
 681                 U48(self.commitment_transaction_number_obscure_factor).write(writer)?;
 682
 683                 match self.key_storage {
 684                         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 } => {
 685                                 writer.write_all(&[0; 1])?;
 686                                 writer.write_all(&revocation_base_key[..])?;
 687                                 writer.write_all(&htlc_base_key[..])?;
 688                                 writer.write_all(&delayed_payment_base_key[..])?;
 689                                 writer.write_all(&payment_base_key[..])?;
 690                                 writer.write_all(&shutdown_pubkey.serialize())?;
 691                                 if let Some(ref prev_latest_per_commitment_point) = *prev_latest_per_commitment_point {
 692                                         writer.write_all(&[1; 1])?;
 693                                         writer.write_all(&prev_latest_per_commitment_point.serialize())?;
 694                                 } else {
 695                                         writer.write_all(&[0; 1])?;
 696                                 }
 697                                 if let Some(ref latest_per_commitment_point) = *latest_per_commitment_point {
 698                                         writer.write_all(&[1; 1])?;
 699                                         writer.write_all(&latest_per_commitment_point.serialize())?;
 700                                 } else {
 701                                         writer.write_all(&[0; 1])?;
 702                                 }
 703                                 match funding_info  {
 704                                         &Some((ref outpoint, ref script)) => {
 705                                                 writer.write_all(&outpoint.txid[..])?;
 706                                                 writer.write_all(&byte_utils::be16_to_array(outpoint.index))?;
 707                                                 script.write(writer)?;
 708                                         },
 709                                         &None => {
 710                                                 debug_assert!(false, "Try to serialize a useless Local monitor !");
 711                                         },
 712                                 }
 713                         },
 714                         Storage::Watchtower { .. } => unimplemented!(),
 715                 }
 716
 717                 writer.write_all(&self.their_htlc_base_key.as_ref().unwrap().serialize())?;
 718                 writer.write_all(&self.their_delayed_payment_base_key.as_ref().unwrap().serialize())?;
 719
 720                 match self.their_cur_revocation_points {
 721                         Some((idx, pubkey, second_option)) => {
 722                                 writer.write_all(&byte_utils::be48_to_array(idx))?;
 723                                 writer.write_all(&pubkey.serialize())?;
 724                                 match second_option {
 725                                         Some(second_pubkey) => {
 726                                                 writer.write_all(&second_pubkey.serialize())?;
 727                                         },
 728                                         None => {
 729                                                 writer.write_all(&[0; 33])?;
 730                                         },
 731                                 }
 732                         },
 733                         None => {
 734                                 writer.write_all(&byte_utils::be48_to_array(0))?;
 735                         },
 736                 }
 737
 738                 writer.write_all(&byte_utils::be16_to_array(self.our_to_self_delay))?;
 739                 writer.write_all(&byte_utils::be16_to_array(self.their_to_self_delay.unwrap()))?;
 740
 741                 for &(ref secret, ref idx) in self.old_secrets.iter() {
 742                         writer.write_all(secret)?;
 743                         writer.write_all(&byte_utils::be64_to_array(*idx))?;
 744                 }
 745
 746                 macro_rules! serialize_htlc_in_commitment {
 747                         ($htlc_output: expr) => {
 748                                 writer.write_all(&[$htlc_output.offered as u8; 1])?;
 749                                 writer.write_all(&byte_utils::be64_to_array($htlc_output.amount_msat))?;
 750                                 writer.write_all(&byte_utils::be32_to_array($htlc_output.cltv_expiry))?;
 751                                 writer.write_all(&$htlc_output.payment_hash)?;
 752                                 writer.write_all(&byte_utils::be32_to_array($htlc_output.transaction_output_index))?;
 753                         }
 754                 }
 755
 756                 writer.write_all(&byte_utils::be64_to_array(self.remote_claimable_outpoints.len() as u64))?;
 757                 for (ref txid, ref htlc_outputs) in self.remote_claimable_outpoints.iter() {
 758                         writer.write_all(&txid[..])?;
 759                         writer.write_all(&byte_utils::be64_to_array(htlc_outputs.len() as u64))?;
 760                         for htlc_output in htlc_outputs.iter() {
 761                                 serialize_htlc_in_commitment!(htlc_output);
 762                         }
 763                 }
 764
 765                 writer.write_all(&byte_utils::be64_to_array(self.remote_commitment_txn_on_chain.len() as u64))?;
 766                 for (ref txid, &(commitment_number, ref txouts)) in self.remote_commitment_txn_on_chain.iter() {
 767                         writer.write_all(&txid[..])?;
 768                         writer.write_all(&byte_utils::be48_to_array(commitment_number))?;
 769                         (txouts.len() as u64).write(writer)?;
 770                         for script in txouts.iter() {
 771                                 script.write(writer)?;
 772                         }
 773                 }
 774
 775                 if for_local_storage {
 776                         writer.write_all(&byte_utils::be64_to_array(self.remote_hash_commitment_number.len() as u64))?;
 777                         for (ref payment_hash, commitment_number) in self.remote_hash_commitment_number.iter() {
 778                                 writer.write_all(*payment_hash)?;
 779                                 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
 780                         }
 781                 } else {
 782                         writer.write_all(&byte_utils::be64_to_array(0))?;
 783                 }
 784
 785                 macro_rules! serialize_local_tx {
 786                         ($local_tx: expr) => {
 787                                 if let Err(e) = $local_tx.tx.consensus_encode(&mut WriterWriteAdaptor(writer)) {
 788                                         match e {
 789                                                 encode::Error::Io(e) => return Err(e),
 790                                                 _ => panic!("local tx must have been well-formed!"),
 791                                         }
 792                                 }
 793
 794                                 writer.write_all(&$local_tx.revocation_key.serialize())?;
 795                                 writer.write_all(&$local_tx.a_htlc_key.serialize())?;
 796                                 writer.write_all(&$local_tx.b_htlc_key.serialize())?;
 797                                 writer.write_all(&$local_tx.delayed_payment_key.serialize())?;
 798
 799                                 writer.write_all(&byte_utils::be64_to_array($local_tx.feerate_per_kw))?;
 800                                 writer.write_all(&byte_utils::be64_to_array($local_tx.htlc_outputs.len() as u64))?;
 801                                 for &(ref htlc_output, ref their_sig, ref our_sig) in $local_tx.htlc_outputs.iter() {
 802                                         serialize_htlc_in_commitment!(htlc_output);
 803                                         writer.write_all(&their_sig.serialize_compact(&self.secp_ctx))?;
 804                                         writer.write_all(&our_sig.serialize_compact(&self.secp_ctx))?;
 805                                 }
 806                         }
 807                 }
 808
 809                 if let Some(ref prev_local_tx) = self.prev_local_signed_commitment_tx {
 810                         writer.write_all(&[1; 1])?;
 811                         serialize_local_tx!(prev_local_tx);
 812                 } else {
 813                         writer.write_all(&[0; 1])?;
 814                 }
 815
 816                 if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
 817                         writer.write_all(&[1; 1])?;
 818                         serialize_local_tx!(cur_local_tx);
 819                 } else {
 820                         writer.write_all(&[0; 1])?;
 821                 }
 822
 823                 if for_local_storage {
 824                         writer.write_all(&byte_utils::be48_to_array(self.current_remote_commitment_number))?;
 825                 } else {
 826                         writer.write_all(&byte_utils::be48_to_array(0))?;
 827                 }
 828
 829                 writer.write_all(&byte_utils::be64_to_array(self.payment_preimages.len() as u64))?;
 830                 for payment_preimage in self.payment_preimages.values() {
 831                         writer.write_all(payment_preimage)?;
 832                 }
 833
 834                 self.last_block_hash.write(writer)?;
 835                 self.destination_script.write(writer)?;
 836
 837                 Ok(())
 838         }
 839
 840         /// Writes this monitor into the given writer, suitable for writing to disk.
 841         ///
 842         /// Note that the deserializer is only implemented for (Sha256dHash, ChannelMonitor), which
 843         /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
 844         /// the "reorg path" (ie not just starting at the same height but starting at the highest
 845         /// common block that appears on your best chain as well as on the chain which contains the
 846         /// last block hash returned) upon deserializing the object!
 847         pub fn write_for_disk<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
 848                 self.write(writer, true)
 849         }
 850
 851         /// Encodes this monitor into the given writer, suitable for sending to a remote watchtower
 852         ///
 853         /// Note that the deserializer is only implemented for (Sha256dHash, ChannelMonitor), which
 854         /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
 855         /// the "reorg path" (ie not just starting at the same height but starting at the highest
 856         /// common block that appears on your best chain as well as on the chain which contains the
 857         /// last block hash returned) upon deserializing the object!
 858         pub fn write_for_watchtower<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
 859                 self.write(writer, false)
 860         }
 861
 862         //TODO: Functions to serialize/deserialize (with different forms depending on which information
 863         //we want to leave out (eg funding_txo, etc).
 864
 865         /// Can only fail if idx is < get_min_seen_secret
 866         pub(super) fn get_secret(&self, idx: u64) -> Option<[u8; 32]> {
 867                 for i in 0..self.old_secrets.len() {
 868                         if (idx & (!((1 << i) - 1))) == self.old_secrets[i].1 {
 869                                 return Some(ChannelMonitor::derive_secret(self.old_secrets[i].0, i as u8, idx))
 870                         }
 871                 }
 872                 assert!(idx < self.get_min_seen_secret());
 873                 None
 874         }
 875
 876         pub(super) fn get_min_seen_secret(&self) -> u64 {
 877                 //TODO This can be optimized?
 878                 let mut min = 1 << 48;
 879                 for &(_, idx) in self.old_secrets.iter() {
 880                         if idx < min {
 881                                 min = idx;
 882                         }
 883                 }
 884                 min
 885         }
 886
 887         pub(super) fn get_cur_remote_commitment_number(&self) -> u64 {
 888                 self.current_remote_commitment_number
 889         }
 890
 891         pub(super) fn get_cur_local_commitment_number(&self) -> u64 {
 892                 if let &Some(ref local_tx) = &self.current_local_signed_commitment_tx {
 893                         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)
 894                 } else { 0xffff_ffff_ffff }
 895         }
 896
 897         /// Attempts to claim a remote commitment transaction's outputs using the revocation key and
 898         /// data in remote_claimable_outpoints. Will directly claim any HTLC outputs which expire at a
 899         /// height > height + CLTV_SHARED_CLAIM_BUFFER. In any case, will install monitoring for
 900         /// HTLC-Success/HTLC-Timeout transactions.
 901         fn check_spend_remote_transaction(&mut self, tx: &Transaction, height: u32) -> (Vec<Transaction>, (Sha256dHash, Vec<TxOut>), Vec<SpendableOutputDescriptor>) {
 902                 // Most secp and related errors trying to create keys means we have no hope of constructing
 903                 // a spend transaction...so we return no transactions to broadcast
 904                 let mut txn_to_broadcast = Vec::new();
 905                 let mut watch_outputs = Vec::new();
 906                 let mut spendable_outputs = Vec::new();
 907
 908                 let commitment_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
 909                 let per_commitment_option = self.remote_claimable_outpoints.get(&commitment_txid);
 910
 911                 macro_rules! ignore_error {
 912                         ( $thing : expr ) => {
 913                                 match $thing {
 914                                         Ok(a) => a,
 915                                         Err(_) => return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs)
 916                                 }
 917                         };
 918                 }
 919
 920                 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);
 921                 if commitment_number >= self.get_min_seen_secret() {
 922                         let secret = self.get_secret(commitment_number).unwrap();
 923                         let per_commitment_key = ignore_error!(SecretKey::from_slice(&self.secp_ctx, &secret));
 924                         let (revocation_pubkey, b_htlc_key, local_payment_key) = match self.key_storage {
 925                                 Storage::Local { ref revocation_base_key, ref htlc_base_key, ref payment_base_key, .. } => {
 926                                         let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
 927                                         (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &PublicKey::from_secret_key(&self.secp_ctx, &revocation_base_key))),
 928                                         ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &PublicKey::from_secret_key(&self.secp_ctx, &htlc_base_key))),
 929                                         Some(ignore_error!(chan_utils::derive_private_key(&self.secp_ctx, &per_commitment_point, &payment_base_key))))
 930                                 },
 931                                 Storage::Watchtower { ref revocation_base_key, ref htlc_base_key, .. } => {
 932                                         let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
 933                                         (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &revocation_base_key)),
 934                                         ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &htlc_base_key)),
 935                                         None)
 936                                 },
 937                         };
 938                         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()));
 939                         let a_htlc_key = match self.their_htlc_base_key {
 940                                 None => return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs),
 941                                 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)),
 942                         };
 943
 944                         let revokeable_redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.our_to_self_delay, &delayed_key);
 945                         let revokeable_p2wsh = revokeable_redeemscript.to_v0_p2wsh();
 946
 947                         let local_payment_p2wpkh = if let Some(payment_key) = local_payment_key {
 948                                 // Note that the Network here is ignored as we immediately drop the address for the
 949                                 // script_pubkey version.
 950                                 let payment_hash160 = Hash160::from_data(&PublicKey::from_secret_key(&self.secp_ctx, &payment_key).serialize());
 951                                 Some(Builder::new().push_opcode(opcodes::All::OP_PUSHBYTES_0).push_slice(&payment_hash160[..]).into_script())
 952                         } else { None };
 953
 954                         let mut total_value = 0;
 955                         let mut values = Vec::new();
 956                         let mut inputs = Vec::new();
 957                         let mut htlc_idxs = Vec::new();
 958
 959                         for (idx, outp) in tx.output.iter().enumerate() {
 960                                 if outp.script_pubkey == revokeable_p2wsh {
 961                                         inputs.push(TxIn {
 962                                                 previous_output: BitcoinOutPoint {
 963                                                         txid: commitment_txid,
 964                                                         vout: idx as u32,
 965                                                 },
 966                                                 script_sig: Script::new(),
 967                                                 sequence: 0xfffffffd,
 968                                                 witness: Vec::new(),
 969                                         });
 970                                         htlc_idxs.push(None);
 971                                         values.push(outp.value);
 972                                         total_value += outp.value;
 973                                 } else if Some(&outp.script_pubkey) == local_payment_p2wpkh.as_ref() {
 974                                         spendable_outputs.push(SpendableOutputDescriptor::DynamicOutputP2WPKH {
 975                                                 outpoint: BitcoinOutPoint { txid: commitment_txid, vout: idx as u32 },
 976                                                 key: local_payment_key.unwrap(),
 977                                                 output: outp.clone(),
 978                                         });
 979                                 }
 980                         }
 981
 982                         macro_rules! sign_input {
 983                                 ($sighash_parts: expr, $input: expr, $htlc_idx: expr, $amount: expr) => {
 984                                         {
 985                                                 let (sig, redeemscript) = match self.key_storage {
 986                                                         Storage::Local { ref revocation_base_key, .. } => {
 987                                                                 let redeemscript = if $htlc_idx.is_none() { revokeable_redeemscript.clone() } else {
 988                                                                         let htlc = &per_commitment_option.unwrap()[$htlc_idx.unwrap()];
 989                                                                         chan_utils::get_htlc_redeemscript_with_explicit_keys(htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey)
 990                                                                 };
 991                                                                 let sighash = ignore_error!(Message::from_slice(&$sighash_parts.sighash_all(&$input, &redeemscript, $amount)[..]));
 992                                                                 let revocation_key = ignore_error!(chan_utils::derive_private_revocation_key(&self.secp_ctx, &per_commitment_key, &revocation_base_key));
 993                                                                 (self.secp_ctx.sign(&sighash, &revocation_key), redeemscript)
 994                                                         },
 995                                                         Storage::Watchtower { .. } => {
 996                                                                 unimplemented!();
 997                                                         }
 998                                                 };
 999                                                 $input.witness.push(sig.serialize_der(&self.secp_ctx).to_vec());
1000                                                 $input.witness[0].push(SigHashType::All as u8);
1001                                                 if $htlc_idx.is_none() {
1002                                                         $input.witness.push(vec!(1));
1003                                                 } else {
1004                                                         $input.witness.push(revocation_pubkey.serialize().to_vec());
1005                                                 }
1006                                                 $input.witness.push(redeemscript.into_bytes());
1007                                         }
1008                                 }
1009                         }
1010
1011                         if let Some(per_commitment_data) = per_commitment_option {
1012                                 inputs.reserve_exact(per_commitment_data.len());
1013
1014                                 for (idx, htlc) in per_commitment_data.iter().enumerate() {
1015                                         let expected_script = chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey);
1016                                         if htlc.transaction_output_index as usize >= tx.output.len() ||
1017                                                         tx.output[htlc.transaction_output_index as usize].value != htlc.amount_msat / 1000 ||
1018                                                         tx.output[htlc.transaction_output_index as usize].script_pubkey != expected_script.to_v0_p2wsh() {
1019                                                 return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs); // Corrupted per_commitment_data, fuck this user
1020                                         }
1021                                         let input = TxIn {
1022                                                 previous_output: BitcoinOutPoint {
1023                                                         txid: commitment_txid,
1024                                                         vout: htlc.transaction_output_index,
1025                                                 },
1026                                                 script_sig: Script::new(),
1027                                                 sequence: 0xfffffffd,
1028                                                 witness: Vec::new(),
1029                                         };
1030                                         if htlc.cltv_expiry > height + CLTV_SHARED_CLAIM_BUFFER {
1031                                                 inputs.push(input);
1032                                                 htlc_idxs.push(Some(idx));
1033                                                 values.push(tx.output[htlc.transaction_output_index as usize].value);
1034                                                 total_value += htlc.amount_msat / 1000;
1035                                         } else {
1036                                                 let mut single_htlc_tx = Transaction {
1037                                                         version: 2,
1038                                                         lock_time: 0,
1039                                                         input: vec![input],
1040                                                         output: vec!(TxOut {
1041                                                                 script_pubkey: self.destination_script.clone(),
1042                                                                 value: htlc.amount_msat / 1000, //TODO: - fee
1043                                                         }),
1044                                                 };
1045                                                 let sighash_parts = bip143::SighashComponents::new(&single_htlc_tx);
1046                                                 sign_input!(sighash_parts, single_htlc_tx.input[0], Some(idx), htlc.amount_msat / 1000);
1047                                                 txn_to_broadcast.push(single_htlc_tx);
1048                                         }
1049                                 }
1050                         }
1051
1052                         if !inputs.is_empty() || !txn_to_broadcast.is_empty() { // ie we're confident this is actually ours
1053                                 // We're definitely a remote commitment transaction!
1054                                 watch_outputs.append(&mut tx.output.clone());
1055                                 self.remote_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
1056                         }
1057                         if inputs.is_empty() { return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs); } // Nothing to be done...probably a false positive/local tx
1058
1059                         let outputs = vec!(TxOut {
1060                                 script_pubkey: self.destination_script.clone(),
1061                                 value: total_value, //TODO: - fee
1062                         });
1063                         let mut spend_tx = Transaction {
1064                                 version: 2,
1065                                 lock_time: 0,
1066                                 input: inputs,
1067                                 output: outputs,
1068                         };
1069
1070                         let mut values_drain = values.drain(..);
1071                         let sighash_parts = bip143::SighashComponents::new(&spend_tx);
1072
1073                         for (input, htlc_idx) in spend_tx.input.iter_mut().zip(htlc_idxs.iter()) {
1074                                 let value = values_drain.next().unwrap();
1075                                 sign_input!(sighash_parts, input, htlc_idx, value);
1076                         }
1077
1078                         spendable_outputs.push(SpendableOutputDescriptor::StaticOutput {
1079                                 outpoint: BitcoinOutPoint { txid: spend_tx.txid(), vout: 0 },
1080                                 output: spend_tx.output[0].clone(),
1081                         });
1082                         txn_to_broadcast.push(spend_tx);
1083                 } else if let Some(per_commitment_data) = per_commitment_option {
1084                         // While this isn't useful yet, there is a potential race where if a counterparty
1085                         // revokes a state at the same time as the commitment transaction for that state is
1086                         // confirmed, and the watchtower receives the block before the user, the user could
1087                         // upload a new ChannelMonitor with the revocation secret but the watchtower has
1088                         // already processed the block, resulting in the remote_commitment_txn_on_chain entry
1089                         // not being generated by the above conditional. Thus, to be safe, we go ahead and
1090                         // insert it here.
1091                         watch_outputs.append(&mut tx.output.clone());
1092                         self.remote_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
1093
1094                         if let Some(revocation_points) = self.their_cur_revocation_points {
1095                                 let revocation_point_option =
1096                                         if revocation_points.0 == commitment_number { Some(&revocation_points.1) }
1097                                         else if let Some(point) = revocation_points.2.as_ref() {
1098                                                 if revocation_points.0 == commitment_number + 1 { Some(point) } else { None }
1099                                         } else { None };
1100                                 if let Some(revocation_point) = revocation_point_option {
1101                                         let (revocation_pubkey, b_htlc_key) = match self.key_storage {
1102                                                 Storage::Local { ref revocation_base_key, ref htlc_base_key, .. } => {
1103                                                         (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, revocation_point, &PublicKey::from_secret_key(&self.secp_ctx, &revocation_base_key))),
1104                                                         ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &PublicKey::from_secret_key(&self.secp_ctx, &htlc_base_key))))
1105                                                 },
1106                                                 Storage::Watchtower { ref revocation_base_key, ref htlc_base_key, .. } => {
1107                                                         (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, revocation_point, &revocation_base_key)),
1108                                                         ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &htlc_base_key)))
1109                                                 },
1110                                         };
1111                                         let a_htlc_key = match self.their_htlc_base_key {
1112                                                 None => return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs),
1113                                                 Some(their_htlc_base_key) => ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &their_htlc_base_key)),
1114                                         };
1115
1116                                         for (idx, outp) in tx.output.iter().enumerate() {
1117                                                 if outp.script_pubkey.is_v0_p2wpkh() {
1118                                                         match self.key_storage {
1119                                                                 Storage::Local { ref payment_base_key, .. } => {
1120                                                                         if let Ok(local_key) = chan_utils::derive_private_key(&self.secp_ctx, &revocation_point, &payment_base_key) {
1121                                                                                 spendable_outputs.push(SpendableOutputDescriptor::DynamicOutputP2WPKH {
1122                                                                                         outpoint: BitcoinOutPoint { txid: commitment_txid, vout: idx as u32 },
1123                                                                                         key: local_key,
1124                                                                                         output: outp.clone(),
1125                                                                                 });
1126                                                                         }
1127                                                                 },
1128                                                                 Storage::Watchtower { .. } => {}
1129                                                         }
1130                                                         break; // Only to_remote ouput is claimable
1131                                                 }
1132                                         }
1133
1134                                         let mut total_value = 0;
1135                                         let mut values = Vec::new();
1136                                         let mut inputs = Vec::new();
1137
1138                                         macro_rules! sign_input {
1139                                                 ($sighash_parts: expr, $input: expr, $amount: expr, $preimage: expr) => {
1140                                                         {
1141                                                                 let (sig, redeemscript) = match self.key_storage {
1142                                                                         Storage::Local { ref htlc_base_key, .. } => {
1143                                                                                 let htlc = &per_commitment_option.unwrap()[$input.sequence as usize];
1144                                                                                 let redeemscript = chan_utils::get_htlc_redeemscript_with_explicit_keys(htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey);
1145                                                                                 let sighash = ignore_error!(Message::from_slice(&$sighash_parts.sighash_all(&$input, &redeemscript, $amount)[..]));
1146                                                                                 let htlc_key = ignore_error!(chan_utils::derive_private_key(&self.secp_ctx, revocation_point, &htlc_base_key));
1147                                                                                 (self.secp_ctx.sign(&sighash, &htlc_key), redeemscript)
1148                                                                         },
1149                                                                         Storage::Watchtower { .. } => {
1150                                                                                 unimplemented!();
1151                                                                         }
1152                                                                 };
1153                                                                 $input.witness.push(sig.serialize_der(&self.secp_ctx).to_vec());
1154                                                                 $input.witness[0].push(SigHashType::All as u8);
1155                                                                 $input.witness.push($preimage);
1156                                                                 $input.witness.push(redeemscript.into_bytes());
1157                                                         }
1158                                                 }
1159                                         }
1160
1161                                         for (idx, htlc) in per_commitment_data.iter().enumerate() {
1162                                                 let expected_script = chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey);
1163                                                 if htlc.transaction_output_index as usize >= tx.output.len() ||
1164                                                                 tx.output[htlc.transaction_output_index as usize].value != htlc.amount_msat / 1000 ||
1165                                                                 tx.output[htlc.transaction_output_index as usize].script_pubkey != expected_script.to_v0_p2wsh() {
1166                                                         return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs); // Corrupted per_commitment_data, fuck this user
1167                                                 }
1168                                                 if let Some(payment_preimage) = self.payment_preimages.get(&htlc.payment_hash) {
1169                                                         let input = TxIn {
1170                                                                 previous_output: BitcoinOutPoint {
1171                                                                         txid: commitment_txid,
1172                                                                         vout: htlc.transaction_output_index,
1173                                                                 },
1174                                                                 script_sig: Script::new(),
1175                                                                 sequence: idx as u32, // reset to 0xfffffffd in sign_input
1176                                                                 witness: Vec::new(),
1177                                                         };
1178                                                         if htlc.cltv_expiry > height + CLTV_SHARED_CLAIM_BUFFER {
1179                                                                 inputs.push(input);
1180                                                                 values.push((tx.output[htlc.transaction_output_index as usize].value, payment_preimage));
1181                                                                 total_value += htlc.amount_msat / 1000;
1182                                                         } else {
1183                                                                 let mut single_htlc_tx = Transaction {
1184                                                                         version: 2,
1185                                                                         lock_time: 0,
1186                                                                         input: vec![input],
1187                                                                         output: vec!(TxOut {
1188                                                                                 script_pubkey: self.destination_script.clone(),
1189                                                                                 value: htlc.amount_msat / 1000, //TODO: - fee
1190                                                                         }),
1191                                                                 };
1192                                                                 let sighash_parts = bip143::SighashComponents::new(&single_htlc_tx);
1193                                                                 sign_input!(sighash_parts, single_htlc_tx.input[0], htlc.amount_msat / 1000, payment_preimage.to_vec());
1194                                                                 spendable_outputs.push(SpendableOutputDescriptor::StaticOutput {
1195                                                                         outpoint: BitcoinOutPoint { txid: single_htlc_tx.txid(), vout: 0 },
1196                                                                         output: single_htlc_tx.output[0].clone(),
1197                                                                 });
1198                                                                 txn_to_broadcast.push(single_htlc_tx);
1199                                                         }
1200                                                 }
1201                                         }
1202
1203                                         if inputs.is_empty() { return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs); } // Nothing to be done...probably a false positive/local tx
1204
1205                                         let outputs = vec!(TxOut {
1206                                                 script_pubkey: self.destination_script.clone(),
1207                                                 value: total_value, //TODO: - fee
1208                                         });
1209                                         let mut spend_tx = Transaction {
1210                                                 version: 2,
1211                                                 lock_time: 0,
1212                                                 input: inputs,
1213                                                 output: outputs,
1214                                         };
1215
1216                                         let mut values_drain = values.drain(..);
1217                                         let sighash_parts = bip143::SighashComponents::new(&spend_tx);
1218
1219                                         for input in spend_tx.input.iter_mut() {
1220                                                 let value = values_drain.next().unwrap();
1221                                                 sign_input!(sighash_parts, input, value.0, value.1.to_vec());
1222                                         }
1223
1224                                         spendable_outputs.push(SpendableOutputDescriptor::StaticOutput {
1225                                                 outpoint: BitcoinOutPoint { txid: spend_tx.txid(), vout: 0 },
1226                                                 output: spend_tx.output[0].clone(),
1227                                         });
1228                                         txn_to_broadcast.push(spend_tx);
1229                                 }
1230                         }
1231                 }
1232
1233                 (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs)
1234         }
1235
1236         /// Attempst to claim a remote HTLC-Success/HTLC-Timeout s outputs using the revocation key
1237         fn check_spend_remote_htlc(&self, tx: &Transaction, commitment_number: u64) -> (Option<Transaction>, Option<SpendableOutputDescriptor>) {
1238                 if tx.input.len() != 1 || tx.output.len() != 1 {
1239                         return (None, None)
1240                 }
1241
1242                 macro_rules! ignore_error {
1243                         ( $thing : expr ) => {
1244                                 match $thing {
1245                                         Ok(a) => a,
1246                                         Err(_) => return (None, None)
1247                                 }
1248                         };
1249                 }
1250
1251                 let secret = if let Some(secret) = self.get_secret(commitment_number) { secret } else { return (None, None); };
1252                 let per_commitment_key = ignore_error!(SecretKey::from_slice(&self.secp_ctx, &secret));
1253                 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1254                 let revocation_pubkey = match self.key_storage {
1255                         Storage::Local { ref revocation_base_key, .. } => {
1256                                 ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &PublicKey::from_secret_key(&self.secp_ctx, &revocation_base_key)))
1257                         },
1258                         Storage::Watchtower { ref revocation_base_key, .. } => {
1259                                 ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &revocation_base_key))
1260                         },
1261                 };
1262                 let delayed_key = match self.their_delayed_payment_base_key {
1263                         None => return (None, None),
1264                         Some(their_delayed_payment_base_key) => ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &their_delayed_payment_base_key)),
1265                 };
1266                 let redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.their_to_self_delay.unwrap(), &delayed_key);
1267                 let revokeable_p2wsh = redeemscript.to_v0_p2wsh();
1268                 let htlc_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
1269
1270                 let mut inputs = Vec::new();
1271                 let mut amount = 0;
1272
1273                 if tx.output[0].script_pubkey == revokeable_p2wsh { //HTLC transactions have one txin, one txout
1274                         inputs.push(TxIn {
1275                                 previous_output: BitcoinOutPoint {
1276                                         txid: htlc_txid,
1277                                         vout: 0,
1278                                 },
1279                                 script_sig: Script::new(),
1280                                 sequence: 0xfffffffd,
1281                                 witness: Vec::new(),
1282                         });
1283                         amount = tx.output[0].value;
1284                 }
1285
1286                 if !inputs.is_empty() {
1287                         let outputs = vec!(TxOut {
1288                                 script_pubkey: self.destination_script.clone(),
1289                                 value: amount, //TODO: - fee
1290                         });
1291
1292                         let mut spend_tx = Transaction {
1293                                 version: 2,
1294                                 lock_time: 0,
1295                                 input: inputs,
1296                                 output: outputs,
1297                         };
1298
1299                         let sighash_parts = bip143::SighashComponents::new(&spend_tx);
1300
1301                         let sig = match self.key_storage {
1302                                 Storage::Local { ref revocation_base_key, .. } => {
1303                                         let sighash = ignore_error!(Message::from_slice(&sighash_parts.sighash_all(&spend_tx.input[0], &redeemscript, amount)[..]));
1304                                         let revocation_key = ignore_error!(chan_utils::derive_private_revocation_key(&self.secp_ctx, &per_commitment_key, &revocation_base_key));
1305                                         self.secp_ctx.sign(&sighash, &revocation_key)
1306                                 }
1307                                 Storage::Watchtower { .. } => {
1308                                         unimplemented!();
1309                                 }
1310                         };
1311                         spend_tx.input[0].witness.push(sig.serialize_der(&self.secp_ctx).to_vec());
1312                         spend_tx.input[0].witness[0].push(SigHashType::All as u8);
1313                         spend_tx.input[0].witness.push(vec!(1));
1314                         spend_tx.input[0].witness.push(redeemscript.into_bytes());
1315
1316                         let outpoint = BitcoinOutPoint { txid: spend_tx.txid(), vout: 0 };
1317                         let output = spend_tx.output[0].clone();
1318                         (Some(spend_tx), Some(SpendableOutputDescriptor::StaticOutput { outpoint, output }))
1319                 } else { (None, None) }
1320         }
1321
1322         fn broadcast_by_local_state(&self, local_tx: &LocalSignedTx, per_commitment_point: &Option<PublicKey>, delayed_payment_base_key: &Option<SecretKey>) -> (Vec<Transaction>, Vec<SpendableOutputDescriptor>) {
1323                 let mut res = Vec::with_capacity(local_tx.htlc_outputs.len());
1324                 let mut spendable_outputs = Vec::with_capacity(local_tx.htlc_outputs.len());
1325
1326                 macro_rules! add_dynamic_output {
1327                         ($father_tx: expr, $vout: expr) => {
1328                                 if let Some(ref per_commitment_point) = *per_commitment_point {
1329                                         if let Some(ref delayed_payment_base_key) = *delayed_payment_base_key {
1330                                                 if let Ok(local_delayedkey) = chan_utils::derive_private_key(&self.secp_ctx, per_commitment_point, delayed_payment_base_key) {
1331                                                         spendable_outputs.push(SpendableOutputDescriptor::DynamicOutputP2WSH {
1332                                                                 outpoint: BitcoinOutPoint { txid: $father_tx.txid(), vout: $vout },
1333                                                                 key: local_delayedkey,
1334                                                                 witness_script: chan_utils::get_revokeable_redeemscript(&local_tx.revocation_key, self.our_to_self_delay, &local_tx.delayed_payment_key),
1335                                                                 to_self_delay: self.our_to_self_delay,
1336                                                                 output: $father_tx.output[$vout as usize].clone(),
1337                                                         });
1338                                                 }
1339                                         }
1340                                 }
1341                         }
1342                 }
1343
1344
1345                 let redeemscript = chan_utils::get_revokeable_redeemscript(&local_tx.revocation_key, self.their_to_self_delay.unwrap(), &local_tx.delayed_payment_key);
1346                 let revokeable_p2wsh = redeemscript.to_v0_p2wsh();
1347                 for (idx, output) in local_tx.tx.output.iter().enumerate() {
1348                         if output.script_pubkey == revokeable_p2wsh {
1349                                 add_dynamic_output!(local_tx.tx, idx as u32);
1350                                 break;
1351                         }
1352                 }
1353
1354                 for &(ref htlc, ref their_sig, ref our_sig) in local_tx.htlc_outputs.iter() {
1355                         if htlc.offered {
1356                                 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);
1357
1358                                 htlc_timeout_tx.input[0].witness.push(Vec::new()); // First is the multisig dummy
1359
1360                                 htlc_timeout_tx.input[0].witness.push(their_sig.serialize_der(&self.secp_ctx).to_vec());
1361                                 htlc_timeout_tx.input[0].witness[1].push(SigHashType::All as u8);
1362                                 htlc_timeout_tx.input[0].witness.push(our_sig.serialize_der(&self.secp_ctx).to_vec());
1363                                 htlc_timeout_tx.input[0].witness[2].push(SigHashType::All as u8);
1364
1365                                 htlc_timeout_tx.input[0].witness.push(Vec::new());
1366                                 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());
1367
1368                                 add_dynamic_output!(htlc_timeout_tx, 0);
1369                                 res.push(htlc_timeout_tx);
1370                         } else {
1371                                 if let Some(payment_preimage) = self.payment_preimages.get(&htlc.payment_hash) {
1372                                         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);
1373
1374                                         htlc_success_tx.input[0].witness.push(Vec::new()); // First is the multisig dummy
1375
1376                                         htlc_success_tx.input[0].witness.push(their_sig.serialize_der(&self.secp_ctx).to_vec());
1377                                         htlc_success_tx.input[0].witness[1].push(SigHashType::All as u8);
1378                                         htlc_success_tx.input[0].witness.push(our_sig.serialize_der(&self.secp_ctx).to_vec());
1379                                         htlc_success_tx.input[0].witness[2].push(SigHashType::All as u8);
1380
1381                                         htlc_success_tx.input[0].witness.push(payment_preimage.to_vec());
1382                                         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());
1383
1384                                         add_dynamic_output!(htlc_success_tx, 0);
1385                                         res.push(htlc_success_tx);
1386                                 }
1387                         }
1388                 }
1389
1390                 (res, spendable_outputs)
1391         }
1392
1393         /// Attempts to claim any claimable HTLCs in a commitment transaction which was not (yet)
1394         /// revoked using data in local_claimable_outpoints.
1395         /// Should not be used if check_spend_revoked_transaction succeeds.
1396         fn check_spend_local_transaction(&self, tx: &Transaction, _height: u32) -> (Vec<Transaction>, Vec<SpendableOutputDescriptor>) {
1397                 let commitment_txid = tx.txid();
1398                 if let &Some(ref local_tx) = &self.current_local_signed_commitment_tx {
1399                         if local_tx.txid == commitment_txid {
1400                                 match self.key_storage {
1401                                         Storage::Local { ref delayed_payment_base_key, ref latest_per_commitment_point, .. } => {
1402                                                 return self.broadcast_by_local_state(local_tx, latest_per_commitment_point, &Some(*delayed_payment_base_key));
1403                                         },
1404                                         Storage::Watchtower { .. } => {
1405                                                 return self.broadcast_by_local_state(local_tx, &None, &None);
1406                                         }
1407                                 }
1408                         }
1409                 }
1410                 if let &Some(ref local_tx) = &self.prev_local_signed_commitment_tx {
1411                         if local_tx.txid == commitment_txid {
1412                                 match self.key_storage {
1413                                         Storage::Local { ref delayed_payment_base_key, ref prev_latest_per_commitment_point, .. } => {
1414                                                 return self.broadcast_by_local_state(local_tx, prev_latest_per_commitment_point, &Some(*delayed_payment_base_key));
1415                                         },
1416                                         Storage::Watchtower { .. } => {
1417                                                 return self.broadcast_by_local_state(local_tx, &None, &None);
1418                                         }
1419                                 }
1420                         }
1421                 }
1422                 (Vec::new(), Vec::new())
1423         }
1424
1425         /// Generate a spendable output event when closing_transaction get registered onchain.
1426         fn check_spend_closing_transaction(&self, tx: &Transaction) -> Option<SpendableOutputDescriptor> {
1427                 if tx.input[0].sequence == 0xFFFFFFFF && !tx.input[0].witness.is_empty() && tx.input[0].witness.last().unwrap().len() == 71 {
1428                         match self.key_storage {
1429                                 Storage::Local { ref shutdown_pubkey, .. } =>  {
1430                                         let our_channel_close_key_hash = Hash160::from_data(&shutdown_pubkey.serialize());
1431                                         let shutdown_script = Builder::new().push_opcode(opcodes::All::OP_PUSHBYTES_0).push_slice(&our_channel_close_key_hash[..]).into_script();
1432                                         for (idx, output) in tx.output.iter().enumerate() {
1433                                                 if shutdown_script == output.script_pubkey {
1434                                                         return Some(SpendableOutputDescriptor::StaticOutput {
1435                                                                 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: idx as u32 },
1436                                                                 output: output.clone(),
1437                                                         });
1438                                                 }
1439                                         }
1440                                 }
1441                                 Storage::Watchtower { .. } => {
1442                                         //TODO: we need to ensure an offline client will generate the event when it
1443                                         // cames back online after only the watchtower saw the transaction
1444                                 }
1445                         }
1446                 }
1447                 None
1448         }
1449
1450         /// Used by ChannelManager deserialization to broadcast the latest local state if it's copy of
1451         /// the Channel was out-of-date.
1452         pub(super) fn get_latest_local_commitment_txn(&self) -> Vec<Transaction> {
1453                 if let &Some(ref local_tx) = &self.current_local_signed_commitment_tx {
1454                         let mut res = vec![local_tx.tx.clone()];
1455                         match self.key_storage {
1456                                 Storage::Local { ref delayed_payment_base_key, ref prev_latest_per_commitment_point, .. } => {
1457                                         res.append(&mut self.broadcast_by_local_state(local_tx, prev_latest_per_commitment_point, &Some(*delayed_payment_base_key)).0);
1458                                 },
1459                                 _ => panic!("Can only broadcast by local channelmonitor"),
1460                         };
1461                         res
1462                 } else {
1463                         Vec::new()
1464                 }
1465         }
1466
1467         fn block_connected(&mut self, txn_matched: &[&Transaction], height: u32, block_hash: &Sha256dHash, broadcaster: &BroadcasterInterface)-> (Vec<(Sha256dHash, Vec<TxOut>)>, Vec<SpendableOutputDescriptor>) {
1468                 let mut watch_outputs = Vec::new();
1469                 let mut spendable_outputs = Vec::new();
1470                 for tx in txn_matched {
1471                         if tx.input.len() == 1 {
1472                                 // Assuming our keys were not leaked (in which case we're screwed no matter what),
1473                                 // commitment transactions and HTLC transactions will all only ever have one input,
1474                                 // which is an easy way to filter out any potential non-matching txn for lazy
1475                                 // filters.
1476                                 let prevout = &tx.input[0].previous_output;
1477                                 let mut txn: Vec<Transaction> = Vec::new();
1478                                 let funding_txo = match self.key_storage {
1479                                         Storage::Local { ref funding_info, .. } => {
1480                                                 funding_info.clone()
1481                                         }
1482                                         Storage::Watchtower { .. } => {
1483                                                 unimplemented!();
1484                                         }
1485                                 };
1486                                 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) {
1487                                         let (remote_txn, new_outputs, mut spendable_output) = self.check_spend_remote_transaction(tx, height);
1488                                         txn = remote_txn;
1489                                         spendable_outputs.append(&mut spendable_output);
1490                                         if !new_outputs.1.is_empty() {
1491                                                 watch_outputs.push(new_outputs);
1492                                         }
1493                                         if txn.is_empty() {
1494                                                 let (remote_txn, mut outputs) = self.check_spend_local_transaction(tx, height);
1495                                                 spendable_outputs.append(&mut outputs);
1496                                                 txn = remote_txn;
1497                                         }
1498                                         if !funding_txo.is_none() && txn.is_empty() {
1499                                                 if let Some(spendable_output) = self.check_spend_closing_transaction(tx) {
1500                                                         spendable_outputs.push(spendable_output);
1501                                                 }
1502                                         }
1503                                 } else {
1504                                         if let Some(&(commitment_number, _)) = self.remote_commitment_txn_on_chain.get(&prevout.txid) {
1505                                                 let (tx, spendable_output) = self.check_spend_remote_htlc(tx, commitment_number);
1506                                                 if let Some(tx) = tx {
1507                                                         txn.push(tx);
1508                                                 }
1509                                                 if let Some(spendable_output) = spendable_output {
1510                                                         spendable_outputs.push(spendable_output);
1511                                                 }
1512                                         }
1513                                 }
1514                                 for tx in txn.iter() {
1515                                         broadcaster.broadcast_transaction(tx);
1516                                 }
1517                         }
1518                 }
1519                 if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
1520                         if self.would_broadcast_at_height(height) {
1521                                 broadcaster.broadcast_transaction(&cur_local_tx.tx);
1522                                 match self.key_storage {
1523                                         Storage::Local { ref delayed_payment_base_key, ref latest_per_commitment_point, .. } => {
1524                                                 let (txs, mut outputs) = self.broadcast_by_local_state(&cur_local_tx, latest_per_commitment_point, &Some(*delayed_payment_base_key));
1525                                                 spendable_outputs.append(&mut outputs);
1526                                                 for tx in txs {
1527                                                         broadcaster.broadcast_transaction(&tx);
1528                                                 }
1529                                         },
1530                                         Storage::Watchtower { .. } => {
1531                                                 let (txs, mut outputs) = self.broadcast_by_local_state(&cur_local_tx, &None, &None);
1532                                                 spendable_outputs.append(&mut outputs);
1533                                                 for tx in txs {
1534                                                         broadcaster.broadcast_transaction(&tx);
1535                                                 }
1536                                         }
1537                                 }
1538                         }
1539                 }
1540                 self.last_block_hash = block_hash.clone();
1541                 (watch_outputs, spendable_outputs)
1542         }
1543
1544         pub(super) fn would_broadcast_at_height(&self, height: u32) -> bool {
1545                 if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
1546                         for &(ref htlc, _, _) in cur_local_tx.htlc_outputs.iter() {
1547                                 // For inbound HTLCs which we know the preimage for, we have to ensure we hit the
1548                                 // chain with enough room to claim the HTLC without our counterparty being able to
1549                                 // time out the HTLC first.
1550                                 // For outbound HTLCs which our counterparty hasn't failed/claimed, our primary
1551                                 // concern is being able to claim the corresponding inbound HTLC (on another
1552                                 // channel) before it expires. In fact, we don't even really care if our
1553                                 // counterparty here claims such an outbound HTLC after it expired as long as we
1554                                 // can still claim the corresponding HTLC. Thus, to avoid needlessly hitting the
1555                                 // chain when our counterparty is waiting for expiration to off-chain fail an HTLC
1556                                 // we give ourselves a few blocks of headroom after expiration before going
1557                                 // on-chain for an expired HTLC.
1558                                 // Note that, to avoid a potential attack whereby a node delays claiming an HTLC
1559                                 // from us until we've reached the point where we go on-chain with the
1560                                 // corresponding inbound HTLC, we must ensure that outbound HTLCs go on chain at
1561                                 // least CLTV_CLAIM_BUFFER blocks prior to the inbound HTLC.
1562                                 //  aka outbound_cltv + HTLC_FAIL_TIMEOUT_BLOCKS == height - CLTV_CLAIM_BUFFER
1563                                 //      inbound_cltv == height + CLTV_CLAIM_BUFFER
1564                                 //      outbound_cltv + HTLC_FAIL_TIMEOUT_BLOCKS + CLTV_CLAIM_BUFER <= inbound_cltv - CLTV_CLAIM_BUFFER
1565                                 //      HTLC_FAIL_TIMEOUT_BLOCKS + 2*CLTV_CLAIM_BUFER <= inbound_cltv - outbound_cltv
1566                                 //      HTLC_FAIL_TIMEOUT_BLOCKS + 2*CLTV_CLAIM_BUFER <= CLTV_EXPIRY_DELTA
1567                                 if ( htlc.offered && htlc.cltv_expiry + HTLC_FAIL_TIMEOUT_BLOCKS <= height) ||
1568                                    (!htlc.offered && htlc.cltv_expiry <= height + CLTV_CLAIM_BUFFER && self.payment_preimages.contains_key(&htlc.payment_hash)) {
1569                                         return true;
1570                                 }
1571                         }
1572                 }
1573                 false
1574         }
1575 }
1576
1577 const MAX_ALLOC_SIZE: usize = 64*1024;
1578
1579 impl<R: ::std::io::Read> ReadableArgs<R, Arc<Logger>> for (Sha256dHash, ChannelMonitor) {
1580         fn read(reader: &mut R, logger: Arc<Logger>) -> Result<Self, DecodeError> {
1581                 let secp_ctx = Secp256k1::new();
1582                 macro_rules! unwrap_obj {
1583                         ($key: expr) => {
1584                                 match $key {
1585                                         Ok(res) => res,
1586                                         Err(_) => return Err(DecodeError::InvalidValue),
1587                                 }
1588                         }
1589                 }
1590
1591                 let _ver: u8 = Readable::read(reader)?;
1592                 let min_ver: u8 = Readable::read(reader)?;
1593                 if min_ver > SERIALIZATION_VERSION {
1594                         return Err(DecodeError::UnknownVersion);
1595                 }
1596
1597                 let commitment_transaction_number_obscure_factor = <U48 as Readable<R>>::read(reader)?.0;
1598
1599                 let key_storage = match <u8 as Readable<R>>::read(reader)? {
1600                         0 => {
1601                                 let revocation_base_key = Readable::read(reader)?;
1602                                 let htlc_base_key = Readable::read(reader)?;
1603                                 let delayed_payment_base_key = Readable::read(reader)?;
1604                                 let payment_base_key = Readable::read(reader)?;
1605                                 let shutdown_pubkey = Readable::read(reader)?;
1606                                 let prev_latest_per_commitment_point = match <u8 as Readable<R>>::read(reader)? {
1607                                         0 => None,
1608                                         1 => Some(Readable::read(reader)?),
1609                                         _ => return Err(DecodeError::InvalidValue),
1610                                 };
1611                                 let latest_per_commitment_point = match <u8 as Readable<R>>::read(reader)? {
1612                                         0 => None,
1613                                         1 => Some(Readable::read(reader)?),
1614                                         _ => return Err(DecodeError::InvalidValue),
1615                                 };
1616                                 // Technically this can fail and serialize fail a round-trip, but only for serialization of
1617                                 // barely-init'd ChannelMonitors that we can't do anything with.
1618                                 let outpoint = OutPoint {
1619                                         txid: Readable::read(reader)?,
1620                                         index: Readable::read(reader)?,
1621                                 };
1622                                 let funding_info = Some((outpoint, Readable::read(reader)?));
1623                                 Storage::Local {
1624                                         revocation_base_key,
1625                                         htlc_base_key,
1626                                         delayed_payment_base_key,
1627                                         payment_base_key,
1628                                         shutdown_pubkey,
1629                                         prev_latest_per_commitment_point,
1630                                         latest_per_commitment_point,
1631                                         funding_info,
1632                                 }
1633                         },
1634                         _ => return Err(DecodeError::InvalidValue),
1635                 };
1636
1637                 let their_htlc_base_key = Some(Readable::read(reader)?);
1638                 let their_delayed_payment_base_key = Some(Readable::read(reader)?);
1639
1640                 let their_cur_revocation_points = {
1641                         let first_idx = <U48 as Readable<R>>::read(reader)?.0;
1642                         if first_idx == 0 {
1643                                 None
1644                         } else {
1645                                 let first_point = Readable::read(reader)?;
1646                                 let second_point_slice: [u8; 33] = Readable::read(reader)?;
1647                                 if second_point_slice[0..32] == [0; 32] && second_point_slice[32] == 0 {
1648                                         Some((first_idx, first_point, None))
1649                                 } else {
1650                                         Some((first_idx, first_point, Some(unwrap_obj!(PublicKey::from_slice(&secp_ctx, &second_point_slice)))))
1651                                 }
1652                         }
1653                 };
1654
1655                 let our_to_self_delay: u16 = Readable::read(reader)?;
1656                 let their_to_self_delay: Option<u16> = Some(Readable::read(reader)?);
1657
1658                 let mut old_secrets = [([0; 32], 1 << 48); 49];
1659                 for &mut (ref mut secret, ref mut idx) in old_secrets.iter_mut() {
1660                         *secret = Readable::read(reader)?;
1661                         *idx = Readable::read(reader)?;
1662                 }
1663
1664                 macro_rules! read_htlc_in_commitment {
1665                         () => {
1666                                 {
1667                                         let offered: bool = Readable::read(reader)?;
1668                                         let amount_msat: u64 = Readable::read(reader)?;
1669                                         let cltv_expiry: u32 = Readable::read(reader)?;
1670                                         let payment_hash: [u8; 32] = Readable::read(reader)?;
1671                                         let transaction_output_index: u32 = Readable::read(reader)?;
1672
1673                                         HTLCOutputInCommitment {
1674                                                 offered, amount_msat, cltv_expiry, payment_hash, transaction_output_index
1675                                         }
1676                                 }
1677                         }
1678                 }
1679
1680                 let remote_claimable_outpoints_len: u64 = Readable::read(reader)?;
1681                 let mut remote_claimable_outpoints = HashMap::with_capacity(cmp::min(remote_claimable_outpoints_len as usize, MAX_ALLOC_SIZE / 64));
1682                 for _ in 0..remote_claimable_outpoints_len {
1683                         let txid: Sha256dHash = Readable::read(reader)?;
1684                         let outputs_count: u64 = Readable::read(reader)?;
1685                         let mut outputs = Vec::with_capacity(cmp::min(outputs_count as usize, MAX_ALLOC_SIZE / 32));
1686                         for _ in 0..outputs_count {
1687                                 outputs.push(read_htlc_in_commitment!());
1688                         }
1689                         if let Some(_) = remote_claimable_outpoints.insert(txid, outputs) {
1690                                 return Err(DecodeError::InvalidValue);
1691                         }
1692                 }
1693
1694                 let remote_commitment_txn_on_chain_len: u64 = Readable::read(reader)?;
1695                 let mut remote_commitment_txn_on_chain = HashMap::with_capacity(cmp::min(remote_commitment_txn_on_chain_len as usize, MAX_ALLOC_SIZE / 32));
1696                 for _ in 0..remote_commitment_txn_on_chain_len {
1697                         let txid: Sha256dHash = Readable::read(reader)?;
1698                         let commitment_number = <U48 as Readable<R>>::read(reader)?.0;
1699                         let outputs_count = <u64 as Readable<R>>::read(reader)?;
1700                         let mut outputs = Vec::with_capacity(cmp::min(outputs_count as usize, MAX_ALLOC_SIZE / 8));
1701                         for _ in 0..outputs_count {
1702                                 outputs.push(Readable::read(reader)?);
1703                         }
1704                         if let Some(_) = remote_commitment_txn_on_chain.insert(txid, (commitment_number, outputs)) {
1705                                 return Err(DecodeError::InvalidValue);
1706                         }
1707                 }
1708
1709                 let remote_hash_commitment_number_len: u64 = Readable::read(reader)?;
1710                 let mut remote_hash_commitment_number = HashMap::with_capacity(cmp::min(remote_hash_commitment_number_len as usize, MAX_ALLOC_SIZE / 32));
1711                 for _ in 0..remote_hash_commitment_number_len {
1712                         let txid: [u8; 32] = Readable::read(reader)?;
1713                         let commitment_number = <U48 as Readable<R>>::read(reader)?.0;
1714                         if let Some(_) = remote_hash_commitment_number.insert(txid, commitment_number) {
1715                                 return Err(DecodeError::InvalidValue);
1716                         }
1717                 }
1718
1719                 macro_rules! read_local_tx {
1720                         () => {
1721                                 {
1722                                         let tx = match Transaction::consensus_decode(reader.by_ref()) {
1723                                                 Ok(tx) => tx,
1724                                                 Err(e) => match e {
1725                                                         encode::Error::Io(ioe) => return Err(DecodeError::Io(ioe)),
1726                                                         _ => return Err(DecodeError::InvalidValue),
1727                                                 },
1728                                         };
1729
1730                                         if tx.input.is_empty() {
1731                                                 // Ensure tx didn't hit the 0-input ambiguity case.
1732                                                 return Err(DecodeError::InvalidValue);
1733                                         }
1734
1735                                         let revocation_key = Readable::read(reader)?;
1736                                         let a_htlc_key = Readable::read(reader)?;
1737                                         let b_htlc_key = Readable::read(reader)?;
1738                                         let delayed_payment_key = Readable::read(reader)?;
1739                                         let feerate_per_kw: u64 = Readable::read(reader)?;
1740
1741                                         let htlc_outputs_len: u64 = Readable::read(reader)?;
1742                                         let mut htlc_outputs = Vec::with_capacity(cmp::min(htlc_outputs_len as usize, MAX_ALLOC_SIZE / 128));
1743                                         for _ in 0..htlc_outputs_len {
1744                                                 htlc_outputs.push((read_htlc_in_commitment!(), Readable::read(reader)?, Readable::read(reader)?));
1745                                         }
1746
1747                                         LocalSignedTx {
1748                                                 txid: tx.txid(),
1749                                                 tx, revocation_key, a_htlc_key, b_htlc_key, delayed_payment_key, feerate_per_kw, htlc_outputs
1750                                         }
1751                                 }
1752                         }
1753                 }
1754
1755                 let prev_local_signed_commitment_tx = match <u8 as Readable<R>>::read(reader)? {
1756                         0 => None,
1757                         1 => {
1758                                 Some(read_local_tx!())
1759                         },
1760                         _ => return Err(DecodeError::InvalidValue),
1761                 };
1762
1763                 let current_local_signed_commitment_tx = match <u8 as Readable<R>>::read(reader)? {
1764                         0 => None,
1765                         1 => {
1766                                 Some(read_local_tx!())
1767                         },
1768                         _ => return Err(DecodeError::InvalidValue),
1769                 };
1770
1771                 let current_remote_commitment_number = <U48 as Readable<R>>::read(reader)?.0;
1772
1773                 let payment_preimages_len: u64 = Readable::read(reader)?;
1774                 let mut payment_preimages = HashMap::with_capacity(cmp::min(payment_preimages_len as usize, MAX_ALLOC_SIZE / 32));
1775                 let mut sha = Sha256::new();
1776                 for _ in 0..payment_preimages_len {
1777                         let preimage: [u8; 32] = Readable::read(reader)?;
1778                         sha.reset();
1779                         sha.input(&preimage);
1780                         let mut hash = [0; 32];
1781                         sha.result(&mut hash);
1782                         if let Some(_) = payment_preimages.insert(hash, preimage) {
1783                                 return Err(DecodeError::InvalidValue);
1784                         }
1785                 }
1786
1787                 let last_block_hash: Sha256dHash = Readable::read(reader)?;
1788                 let destination_script = Readable::read(reader)?;
1789
1790                 Ok((last_block_hash.clone(), ChannelMonitor {
1791                         commitment_transaction_number_obscure_factor,
1792
1793                         key_storage,
1794                         their_htlc_base_key,
1795                         their_delayed_payment_base_key,
1796                         their_cur_revocation_points,
1797
1798                         our_to_self_delay,
1799                         their_to_self_delay,
1800
1801                         old_secrets,
1802                         remote_claimable_outpoints,
1803                         remote_commitment_txn_on_chain,
1804                         remote_hash_commitment_number,
1805
1806                         prev_local_signed_commitment_tx,
1807                         current_local_signed_commitment_tx,
1808                         current_remote_commitment_number,
1809
1810                         payment_preimages,
1811
1812                         destination_script,
1813                         last_block_hash,
1814                         secp_ctx,
1815                         logger,
1816                 }))
1817         }
1818
1819 }
1820
1821 #[cfg(test)]
1822 mod tests {
1823         use bitcoin::blockdata::script::Script;
1824         use bitcoin::blockdata::transaction::Transaction;
1825         use crypto::digest::Digest;
1826         use hex;
1827         use ln::channelmonitor::ChannelMonitor;
1828         use ln::chan_utils::{HTLCOutputInCommitment, TxCreationKeys};
1829         use util::sha2::Sha256;
1830         use util::test_utils::TestLogger;
1831         use secp256k1::key::{SecretKey,PublicKey};
1832         use secp256k1::{Secp256k1, Signature};
1833         use rand::{thread_rng,Rng};
1834         use std::sync::Arc;
1835
1836         #[test]
1837         fn test_per_commitment_storage() {
1838                 // Test vectors from BOLT 3:
1839                 let mut secrets: Vec<[u8; 32]> = Vec::new();
1840                 let mut monitor: ChannelMonitor;
1841                 let secp_ctx = Secp256k1::new();
1842                 let logger = Arc::new(TestLogger::new());
1843
1844                 macro_rules! test_secrets {
1845                         () => {
1846                                 let mut idx = 281474976710655;
1847                                 for secret in secrets.iter() {
1848                                         assert_eq!(monitor.get_secret(idx).unwrap(), *secret);
1849                                         idx -= 1;
1850                                 }
1851                                 assert_eq!(monitor.get_min_seen_secret(), idx + 1);
1852                                 assert!(monitor.get_secret(idx).is_none());
1853                         };
1854                 }
1855
1856                 {
1857                         // insert_secret correct sequence
1858                         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());
1859                         secrets.clear();
1860
1861                         secrets.push([0; 32]);
1862                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1863                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1864                         test_secrets!();
1865
1866                         secrets.push([0; 32]);
1867                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1868                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1869                         test_secrets!();
1870
1871                         secrets.push([0; 32]);
1872                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1873                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1874                         test_secrets!();
1875
1876                         secrets.push([0; 32]);
1877                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1878                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
1879                         test_secrets!();
1880
1881                         secrets.push([0; 32]);
1882                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
1883                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
1884                         test_secrets!();
1885
1886                         secrets.push([0; 32]);
1887                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
1888                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
1889                         test_secrets!();
1890
1891                         secrets.push([0; 32]);
1892                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
1893                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
1894                         test_secrets!();
1895
1896                         secrets.push([0; 32]);
1897                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
1898                         monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap();
1899                         test_secrets!();
1900                 }
1901
1902                 {
1903                         // insert_secret #1 incorrect
1904                         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());
1905                         secrets.clear();
1906
1907                         secrets.push([0; 32]);
1908                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
1909                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1910                         test_secrets!();
1911
1912                         secrets.push([0; 32]);
1913                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1914                         assert_eq!(monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap_err().0,
1915                                         "Previous secret did not match new one");
1916                 }
1917
1918                 {
1919                         // insert_secret #2 incorrect (#1 derived from incorrect)
1920                         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());
1921                         secrets.clear();
1922
1923                         secrets.push([0; 32]);
1924                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
1925                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1926                         test_secrets!();
1927
1928                         secrets.push([0; 32]);
1929                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("dddc3a8d14fddf2b68fa8c7fbad2748274937479dd0f8930d5ebb4ab6bd866a3").unwrap());
1930                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1931                         test_secrets!();
1932
1933                         secrets.push([0; 32]);
1934                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
1935                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1936                         test_secrets!();
1937
1938                         secrets.push([0; 32]);
1939                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1940                         assert_eq!(monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap_err().0,
1941                                         "Previous secret did not match new one");
1942                 }
1943
1944                 {
1945                         // insert_secret #3 incorrect
1946                         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());
1947                         secrets.clear();
1948
1949                         secrets.push([0; 32]);
1950                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
1951                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1952                         test_secrets!();
1953
1954                         secrets.push([0; 32]);
1955                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
1956                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1957                         test_secrets!();
1958
1959                         secrets.push([0; 32]);
1960                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c51a18b13e8527e579ec56365482c62f180b7d5760b46e9477dae59e87ed423a").unwrap());
1961                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1962                         test_secrets!();
1963
1964                         secrets.push([0; 32]);
1965                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
1966                         assert_eq!(monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap_err().0,
1967                                         "Previous secret did not match new one");
1968                 }
1969
1970                 {
1971                         // insert_secret #4 incorrect (1,2,3 derived from incorrect)
1972                         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());
1973                         secrets.clear();
1974
1975                         secrets.push([0; 32]);
1976                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap());
1977                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
1978                         test_secrets!();
1979
1980                         secrets.push([0; 32]);
1981                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("dddc3a8d14fddf2b68fa8c7fbad2748274937479dd0f8930d5ebb4ab6bd866a3").unwrap());
1982                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
1983                         test_secrets!();
1984
1985                         secrets.push([0; 32]);
1986                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c51a18b13e8527e579ec56365482c62f180b7d5760b46e9477dae59e87ed423a").unwrap());
1987                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
1988                         test_secrets!();
1989
1990                         secrets.push([0; 32]);
1991                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("ba65d7b0ef55a3ba300d4e87af29868f394f8f138d78a7011669c79b37b936f4").unwrap());
1992                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
1993                         test_secrets!();
1994
1995                         secrets.push([0; 32]);
1996                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
1997                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
1998                         test_secrets!();
1999
2000                         secrets.push([0; 32]);
2001                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
2002                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
2003                         test_secrets!();
2004
2005                         secrets.push([0; 32]);
2006                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
2007                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
2008                         test_secrets!();
2009
2010                         secrets.push([0; 32]);
2011                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
2012                         assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap_err().0,
2013                                         "Previous secret did not match new one");
2014                 }
2015
2016                 {
2017                         // insert_secret #5 incorrect
2018                         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());
2019                         secrets.clear();
2020
2021                         secrets.push([0; 32]);
2022                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2023                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2024                         test_secrets!();
2025
2026                         secrets.push([0; 32]);
2027                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2028                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2029                         test_secrets!();
2030
2031                         secrets.push([0; 32]);
2032                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2033                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2034                         test_secrets!();
2035
2036                         secrets.push([0; 32]);
2037                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2038                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
2039                         test_secrets!();
2040
2041                         secrets.push([0; 32]);
2042                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("631373ad5f9ef654bb3dade742d09504c567edd24320d2fcd68e3cc47e2ff6a6").unwrap());
2043                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
2044                         test_secrets!();
2045
2046                         secrets.push([0; 32]);
2047                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
2048                         assert_eq!(monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap_err().0,
2049                                         "Previous secret did not match new one");
2050                 }
2051
2052                 {
2053                         // insert_secret #6 incorrect (5 derived from incorrect)
2054                         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());
2055                         secrets.clear();
2056
2057                         secrets.push([0; 32]);
2058                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2059                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2060                         test_secrets!();
2061
2062                         secrets.push([0; 32]);
2063                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2064                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2065                         test_secrets!();
2066
2067                         secrets.push([0; 32]);
2068                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2069                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2070                         test_secrets!();
2071
2072                         secrets.push([0; 32]);
2073                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2074                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
2075                         test_secrets!();
2076
2077                         secrets.push([0; 32]);
2078                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("631373ad5f9ef654bb3dade742d09504c567edd24320d2fcd68e3cc47e2ff6a6").unwrap());
2079                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
2080                         test_secrets!();
2081
2082                         secrets.push([0; 32]);
2083                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("b7e76a83668bde38b373970155c868a653304308f9896692f904a23731224bb1").unwrap());
2084                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
2085                         test_secrets!();
2086
2087                         secrets.push([0; 32]);
2088                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
2089                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
2090                         test_secrets!();
2091
2092                         secrets.push([0; 32]);
2093                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
2094                         assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap_err().0,
2095                                         "Previous secret did not match new one");
2096                 }
2097
2098                 {
2099                         // insert_secret #7 incorrect
2100                         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());
2101                         secrets.clear();
2102
2103                         secrets.push([0; 32]);
2104                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2105                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2106                         test_secrets!();
2107
2108                         secrets.push([0; 32]);
2109                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2110                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2111                         test_secrets!();
2112
2113                         secrets.push([0; 32]);
2114                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2115                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2116                         test_secrets!();
2117
2118                         secrets.push([0; 32]);
2119                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2120                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
2121                         test_secrets!();
2122
2123                         secrets.push([0; 32]);
2124                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
2125                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
2126                         test_secrets!();
2127
2128                         secrets.push([0; 32]);
2129                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
2130                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
2131                         test_secrets!();
2132
2133                         secrets.push([0; 32]);
2134                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("e7971de736e01da8ed58b94c2fc216cb1dca9e326f3a96e7194fe8ea8af6c0a3").unwrap());
2135                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
2136                         test_secrets!();
2137
2138                         secrets.push([0; 32]);
2139                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
2140                         assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap_err().0,
2141                                         "Previous secret did not match new one");
2142                 }
2143
2144                 {
2145                         // insert_secret #8 incorrect
2146                         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());
2147                         secrets.clear();
2148
2149                         secrets.push([0; 32]);
2150                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2151                         monitor.provide_secret(281474976710655, secrets.last().unwrap().clone()).unwrap();
2152                         test_secrets!();
2153
2154                         secrets.push([0; 32]);
2155                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2156                         monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap();
2157                         test_secrets!();
2158
2159                         secrets.push([0; 32]);
2160                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2161                         monitor.provide_secret(281474976710653, secrets.last().unwrap().clone()).unwrap();
2162                         test_secrets!();
2163
2164                         secrets.push([0; 32]);
2165                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2166                         monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap();
2167                         test_secrets!();
2168
2169                         secrets.push([0; 32]);
2170                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd").unwrap());
2171                         monitor.provide_secret(281474976710651, secrets.last().unwrap().clone()).unwrap();
2172                         test_secrets!();
2173
2174                         secrets.push([0; 32]);
2175                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
2176                         monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap();
2177                         test_secrets!();
2178
2179                         secrets.push([0; 32]);
2180                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32").unwrap());
2181                         monitor.provide_secret(281474976710649, secrets.last().unwrap().clone()).unwrap();
2182                         test_secrets!();
2183
2184                         secrets.push([0; 32]);
2185                         secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a7efbc61aac46d34f77778bac22c8a20c6a46ca460addc49009bda875ec88fa4").unwrap());
2186                         assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap_err().0,
2187                                         "Previous secret did not match new one");
2188                 }
2189         }
2190
2191         #[test]
2192         fn test_prune_preimages() {
2193                 let secp_ctx = Secp256k1::new();
2194                 let logger = Arc::new(TestLogger::new());
2195                 let dummy_sig = Signature::from_der(&secp_ctx, &hex::decode("3045022100fa86fa9a36a8cd6a7bb8f06a541787d51371d067951a9461d5404de6b928782e02201c8b7c334c10aed8976a3a465be9a28abff4cb23acbf00022295b378ce1fa3cd").unwrap()[..]).unwrap();
2196
2197                 let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap());
2198                 macro_rules! dummy_keys {
2199                         () => {
2200                                 {
2201                                         TxCreationKeys {
2202                                                 per_commitment_point: dummy_key.clone(),
2203                                                 revocation_key: dummy_key.clone(),
2204                                                 a_htlc_key: dummy_key.clone(),
2205                                                 b_htlc_key: dummy_key.clone(),
2206                                                 a_delayed_payment_key: dummy_key.clone(),
2207                                                 b_payment_key: dummy_key.clone(),
2208                                         }
2209                                 }
2210                         }
2211                 }
2212                 let dummy_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
2213
2214                 let mut preimages = Vec::new();
2215                 {
2216                         let mut rng  = thread_rng();
2217                         for _ in 0..20 {
2218                                 let mut preimage = [0; 32];
2219                                 rng.fill_bytes(&mut preimage);
2220                                 let mut sha = Sha256::new();
2221                                 sha.input(&preimage);
2222                                 let mut hash = [0; 32];
2223                                 sha.result(&mut hash);
2224                                 preimages.push((preimage, hash));
2225                         }
2226                 }
2227
2228                 macro_rules! preimages_slice_to_htlc_outputs {
2229                         ($preimages_slice: expr) => {
2230                                 {
2231                                         let mut res = Vec::new();
2232                                         for (idx, preimage) in $preimages_slice.iter().enumerate() {
2233                                                 res.push(HTLCOutputInCommitment {
2234                                                         offered: true,
2235                                                         amount_msat: 0,
2236                                                         cltv_expiry: 0,
2237                                                         payment_hash: preimage.1.clone(),
2238                                                         transaction_output_index: idx as u32,
2239                                                 });
2240                                         }
2241                                         res
2242                                 }
2243                         }
2244                 }
2245                 macro_rules! preimages_to_local_htlcs {
2246                         ($preimages_slice: expr) => {
2247                                 {
2248                                         let mut inp = preimages_slice_to_htlc_outputs!($preimages_slice);
2249                                         let res: Vec<_> = inp.drain(..).map(|e| { (e, dummy_sig.clone(), dummy_sig.clone()) }).collect();
2250                                         res
2251                                 }
2252                         }
2253                 }
2254
2255                 macro_rules! test_preimages_exist {
2256                         ($preimages_slice: expr, $monitor: expr) => {
2257                                 for preimage in $preimages_slice {
2258                                         assert!($monitor.payment_preimages.contains_key(&preimage.1));
2259                                 }
2260                         }
2261                 }
2262
2263                 // Prune with one old state and a local commitment tx holding a few overlaps with the
2264                 // old state.
2265                 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());
2266                 monitor.set_their_to_self_delay(10);
2267
2268                 monitor.provide_latest_local_commitment_tx_info(dummy_tx.clone(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..10]));
2269                 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[5..15]), 281474976710655, dummy_key);
2270                 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[15..20]), 281474976710654, dummy_key);
2271                 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[17..20]), 281474976710653, dummy_key);
2272                 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[18..20]), 281474976710652, dummy_key);
2273                 for &(ref preimage, ref hash) in preimages.iter() {
2274                         monitor.provide_payment_preimage(hash, preimage);
2275                 }
2276
2277                 // Now provide a secret, pruning preimages 10-15
2278                 let mut secret = [0; 32];
2279                 secret[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2280                 monitor.provide_secret(281474976710655, secret.clone()).unwrap();
2281                 assert_eq!(monitor.payment_preimages.len(), 15);
2282                 test_preimages_exist!(&preimages[0..10], monitor);
2283                 test_preimages_exist!(&preimages[15..20], monitor);
2284
2285                 // Now provide a further secret, pruning preimages 15-17
2286                 secret[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2287                 monitor.provide_secret(281474976710654, secret.clone()).unwrap();
2288                 assert_eq!(monitor.payment_preimages.len(), 13);
2289                 test_preimages_exist!(&preimages[0..10], monitor);
2290                 test_preimages_exist!(&preimages[17..20], monitor);
2291
2292                 // Now update local commitment tx info, pruning only element 18 as we still care about the
2293                 // previous commitment tx's preimages too
2294                 monitor.provide_latest_local_commitment_tx_info(dummy_tx.clone(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..5]));
2295                 secret[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2296                 monitor.provide_secret(281474976710653, secret.clone()).unwrap();
2297                 assert_eq!(monitor.payment_preimages.len(), 12);
2298                 test_preimages_exist!(&preimages[0..10], monitor);
2299                 test_preimages_exist!(&preimages[18..20], monitor);
2300
2301                 // But if we do it again, we'll prune 5-10
2302                 monitor.provide_latest_local_commitment_tx_info(dummy_tx.clone(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..3]));
2303                 secret[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2304                 monitor.provide_secret(281474976710652, secret.clone()).unwrap();
2305                 assert_eq!(monitor.payment_preimages.len(), 5);
2306                 test_preimages_exist!(&preimages[0..5], monitor);
2307         }
2308
2309         // Further testing is done in the ChannelManager integration tests.
2310 }